Press Alt + R to read the document text or Alt + P to download or print.
This document contains no pages.
HomeMy WebLinkAboutLUA-08-093 (1 OF 3)_Misc(
--------------~-
Df=V~LOPMl,NT ST,\ND/1RDS -DENSITY AND DIMENSIONS 21Al2 010 -21A17 030
21A.12.010 Purpose. TfH--: ptirpose ot this chapter 1s to establish basic dirrninsionc1I standards
fo1 devi:lorrnent rekitive to residential density ;rnci as \Nell as :;pccific rules tor uencral ;::ipplication The
stdmbrds and rules c1rf~ established to provide flexibility in projf:ct desi~Jn. c1nd rnafntain priv;-:icy between
~rl1ccent usc,s_ (Ord. 10B70 § 338. ln93)
21A 12.020 Interpretation of tables
A. K.C.C_ ?1A.12.030 and ;i·JA.12 040 contai:1 qP.r1cral clen;:;ity and dimension slcmcbrds for thr~
various zones cmd limit1tions :;pcc1f1c to a particular zone(s). /\ddit1pnc:1J rules, exceptions. and
methodolouie:; arc set forth in K CC 21A 12.050 lhrough 21A 12.210
B The density and dimension tables am arr.?Jnged in a rnatrix formc'lt on tvvo sPramtc t~1bics and
are delineated into tvvo generc.11 land use categories:
1. Residential: and
2. Resource and Cornrnerci,:11/lnrlustrial.
C. Development standards are listed down thP. left ~_;1dc of both tablf!s, and the zonP.s ,ire listed cit
t11e tup. The matrix cells contain the rninirnurn dimensional requirnrm~nts of the Lone. The parenthetical
nurdir:rs in the matrix identify specific requirerrnc-nts applica:Jle eilhP.r to cl specific USP. or 7one_ A blank
box indicates that '.here ;-ire no specific requirf:rnents. lf more than one sldndard appears in a cell. each
s1ar1dc1rd will be subject to any applicable p;~renthcticaf footnote fol!owtng tfle standa.rJ (Ord_ 10870 § 33D,
1993).
21A.12.030 Densities and dimensions -residential zones.
A Densities arid dimensions -residP-nf1~11 zones ~cc__ ____ _ r---~-;-RESIDENrlA_L _____ ~~,
--I I ;_ lilJIU\I URfl,c,N llRR/IN
~· RE-Isl cil~f"NTl/ll
N S~RV~ I; f-=------T-
11 A R/\, "' RA-rn RA-}0 R 1 111) 1(-1
'--'~~.~--l--0-,--, -" -. -c,~os,----+-c,,c,,----f-
JsJao •Jui<lC Jul;c du!ac
l'a~e Dnnsit,
L'w,-11,ri~
U111UAcre
M.,rnn"'" [u,a •t) U -1 ~ ~
1211 (f,I
---------l-----' " DMl•tn? Un ~·t.,:,u ~"lac d<J/a• " Ju/ac
lll )7
de/~, ., •l.ar
cc''~',--~~----l-ti,-1 -1-""""'-+----~--M" mum Llon,.,ly ,,, ----+---+W/ ---1--,~,.7,.--t~"~~-,-1 w·C--a,~,,.-, --t~'"7_/-f-cc,~5~,,--
]/_', 1",,c
,',1,rurn•,cn I c,t
)'h:lh
·;;~ n '-~;:~,-,, -+-,-,,-,--! c,~,,~,,--+,,:is""c--l,,cc,, 11
(l)
M,0•1nuu1 Stroo"
.SoU,a,,
],1 t(
(~)
f-L'"~,--~-~ -+-c~--+ M,n,.n,or,, lnlo,;,,, ~f! w,
'"" I~)
\Oft
'"
JOii
1~;,
1011
(~)
1Do't
19}
10ft ,,,
(71 iii
30ft
{/)
" UJ
,11
(171 1111 ,11;. (10) 1rn1 1rn1 111;,
I rnJ I ss1 pH) ;1:i•
'"' '"'
SIi
10 r,
(')
10 II
\fp
1lll1
1~1
5 11
PO)
--
J(I!;
10 ft
'"'
~ fl
(10) Sntback
f-13>1161
cla"' H8i~l1I ,,, r-4°o"'1 4U !l 4~ fl --1----+-~-l-lO 11,--J-,,,s,,,-, --+-,cc,,,,,-·,--r,,occec,
IJ',)
-!-c,~,~,,---,f--;;;"'-,"~+-ceo ti·--1-~.,~,,-l--c,-,,,,~,-+ u> ii-
u n 45~ w~ 8u11 ~1,n
Mntn-uc. lr11FHYiou~ 25% <Ofo 1----c,,~,~--+-,~,~0~~, --frcac~,%--
.-c,irt~rR" Ill) (11) 111)
p~,.,en!a~o(Oj [1~) 11~) :;::
~
B. Development cond1t1ons.
1'11
1:~1
[11) (11)
:1-1) 114) i14) (1-1) (HI
,"251 _ (2~1
F,",0
1 This maximum density may be achieved orily through the application of residential density
incentives in accordance with K.C.C. chapter 21A.34 or transfers of development rights in ,1ccordance with
K.C.C. chc1pter 21A.37, or any r:ombination of density incentive or den~;ify transfer. rv1axirnurn density rn3y
only be exceeded rn accordance with K.C C 21A34 040.F 1 g_ and F.6.
2 Also see K.C.C 21A12.060.
3. These stanchrds may be modified under the provisions for zero-Jot-line and townhouse
developments
{Krnq County 9-2004)
21A-103
K<'--C. Z-IA-"2-
1>8" (.1 1'{ 1,
1) t f\lTBNSt DN2;
lJEVFl OPMENT STANDA1-ms -m,NS1TY AND D1M[NS10NS 21A12 040 -?1A12.050
9. The floor-to-lot ratio for mixed use developments shr.ill conform to K.C.C_ chapter 21A.14
10. Heigh! limits mcJy be increased if portions of the structure building that exceed the basP-
height limit provide one addition;:il foot of strc-;et and interior setback for each foot abow-~ the. ba~,c height
limit, provided the maxirrnm1 height m.?ty f:xcced seventy-five feet only in rn1xcd use developrnenls.
Ncttmg or fencing and support structures for the netting or fencing used to contain golf balls in 1hc
operation of golf coursPs or golf driving rnngP.s are P.xcrnµt from the additioncil interior setback
requirnment provided that the maximum hci~Jht shall not exceed sevP.nty-five feet.
11. AppliGJblc only to Jots containing less than one acre of lot area. Development on lots
contzi'1nlng less than fifteen thousand square feet of lot area shall be governed hy irnµervious surface
standards of the nearest comrarab!e R-4 through 1\-8 zone.
17. See K.C.C. 21A.22.060 for setb;lck requirements in the mineral zone
13. The impervio11s surf;.1ce area for any lot mcJy be increased bcyor:d !tic total amount
permitted in this chapter subJect to approval of a conditional use pcm11il.
14. Required on property !ines ad101nlng rcsidenlial 7011Ps unless c1 stand-alone townhouse
developrnent on property designated commercial outside of center in the urh;:in area 1s proposed to be
located adjacent to property upon which an existing townhrnise development is locatPrl. (Ord. 14190 § 34,
2001 Ord. 14045 § 19, 2001: Ord_ 13086 § 2, 1998: Ord_ 13022 § 17, 1998: Ord_ 12929 § 2, 1997 Ord_
12522 § 4, 1996-Ord 11821 § :1, 1995: Ord_ 11802 § 4, 1995: Ord. 11621 § 42, 1fl94 Ord 10870 § 341,
1993)
21A.12.050 Measurement methods. The following provisions shall bR used to determine
compJizmce with this title:
A. Street setbacks sh<1II be measured from the existing edoe of ;-1 street right-of-wdy or temporary
turnarrnmd, except as prov·1decJ by K.C.C. 21 A.12.150;
B Lot widths shall be measured by scaling .i circle of the applicable ciianieter within t11e
boundaries of the lot, provided thnt an access easement shall not he included witt1in the circle:
C_ Gu ii ding height shall be measured frorn the .:werage finished wc1de to 1he hi~Jhest point of the
roof. The average finist1er. f_JraJe shall be determined by first delineating the srnallest squ~--;;re or rectangle
which c,1n enclose the bui 1,d"ing and then averaging the efevntions taken c1t the midpoint of each side of !he
square or rectangle, provided that the measured elevations do not inr:lucle berms:
D. Lot area shall be the totcJI horizontal !and nrea contained within the houndaries of a lot; and
E. impervious surfc1ce calculations shall not include c1rcas of turf. landscaping, natural vegetation,
or surface wc1tcr flow control or water quality trcatmE-~nt facilities (Ord 13190 § ·16, '!998: Orrl 10870 §
342_ 1993)-
21A 12.060 Minimum urban residential density. fl.•1inimurn density for residential development
in the urhcm areas designated by the Comprehensive Plan shall be based on the table:; in K.C.C.
21A 12_030, adjusted as provided in 21A 12_070 thrrn,gh 21 A 12 080_
A. A proposal m3y be phased, if compliance with the minimum density requirement results in
noncompli;incc with of K_c_c_ chapter 21A_28, if the overall density of the proposal is consislenl with this
section.
B. Minimum density requirements may be waived by King County if the appllcant demonstrates
one or more of the foHowing:
1-The proposed layout of the lots in a subdivision or the buildings in a multiple dwelling
development will not preclude future residential development consistent wiH1 the minimum density or the
zone:
2. The non-sensitive area of the parcel is of a size or configuration that results in lots that cannot
meet the rninimurn dimensional requirements of the zone;
3. In the R-12 lhrough R-48 zones, the area of the parcel required to accommodate storm wnter
facilities exceeds ten percent of the area of the site;
4. The site contains a national, st3te or county historic landmark.
C. A proposal to locate a single resldentlal unit on a lot shall be exempt from the minimum
density requirement provided the applicant either preplans the site by demonstrating that the proposed
single residence would be located in a manner cornpatib/e with future division of the site in a manner that
would meet the minimum density requirements, or locates the dwelling within fifteen feet of one or more of
1hc site's interior lot lines.
(King County 9-2004)
21A-107
'
f
21A.12060 21A12.087 70Nl~JG
D Alter r1;_i!ive rninirnurn derisity rec;uircrncnts may be imposed throtJgh county-arproved
proper'.y specific rlevdopment st;indzirds (P-suffix), c1 sp1c:cial district overlayt; in accordance with K C.C
chc1pter 21A38 or a sulwca p!an (Ord. 14045 § 20, 2001: Ord. 11555 § G, HJSJ4: 10870 § 343, 1993).
21A.12.070 Calculations -allowable dwelling units, lots or floor area. Perrnillt:d rnm1bcr o1
units. or lot~; or floor ;Jrea shall be determined c;1s follows:
A. The allovved nurnbPr of rlwcll1ng units or lots (base density) shall be computed by multiplyin~J
H:e ~;ite ~1rca specified in K.C.C_ /·JA.12.080 by the aVi1licc1hJe rcs1dentic1I b<-1se dt)ris1ty number;
R l he rnaxirnum ck:r·,sity (unit or lot) limits shall be computed by adding the bonus or lr,msfer
units authorized by K C:.C:. ch~-1pters 21/\.34 and 21A.37 to the base units computed under .subsec1ion /\ of
this section:
C The ullowcd floor area, which excludes structured or undcrqround parkiny areas cmd areas
housin9 rncchc1nica/ equipment, shall be computed by applying the floor-to-Jot <'_irea r;itio to the project site
area specified :n K.C.C. 21A 12 080:
D. It calculations result in a fraction, the fraction shall be rounded to the nearest whole number as
follovvs, except as rirovidcd in sc.ibsection E of this section:
·1. Fractions of 0.50 or above shall be rounded up; arid
7 Frc1ct1ons below 0.50 shall be rounded down; and
E For subdivisions Clnd :--~hort subdivisions in the RA and A zones. rounding up of the nurnber of
dewlopmcnt units or lots is not allowed. (Ord. 14 mo § 35. 7001 Ord 14045 § 71, ;,001: Ord. 11927 § 1.
1995: Ord 10870 § 344, 1993)
21A.12.080 Calculations -site 3rea used for base density and maximum density floor area
calculations.
A_ All site areas rnay be used in the cilc11lc1tion of base arid rn<.1x1inum c1llowed residential density
or project floor ,~rea ~xccpt as outlined under the provisions of subsection El of this see-lion
B. Subrncrgcrl lands sh,111 no1 hP credited to·Nctrd base and rnaxirnum density or floor area
c0!culations.
C. For s11bd1vis1ons and shor1 subdivisions in the RA zone, if ca!culatior1s of site orea for base
density result in a frc1c:t1on, the fr8ction shalf be rounded to the nearest whole number as follows·
1. Frac1ions of 0.50 or above shall be rounded up: and
2 Frc.u:tions below 0.50 sil3II lJe rounded down. (Ord 14045 § 22, 2001. Ord 11621 § 43.
Hl!YI Ord. 11:i:i'.l § ::3, 1mM: Ord. 10870 § 345, 1993).
21A.12.085 Calculations -Site area used for minimum density calculations. f\..'lir1irrnnn
density slin!I be determined by:
A Multiolying tire Base Density (Dwelling Units/Acre) as set forth 1n K.C C 21A.12.030/\ hy the
net btiildablc area of the projPct site; and then
B Multiplying the resulting product by the Minimum Density percentage sel forth in K.C.C.
21/\.12.030A or as adjusted pursuant to tile provisions of K.C.C. 21/\.12.087 (Ord. 12549 § 2. 1096:
Ord 11798 § 2, ·1995: Ord. 11555 § 4, 1994).
21A.12.D87 Minimum density adjustments for moderate slopes.
A. For purposes of calculating minirnurn density of sloped siles 1n zones R-4. R-6 and R-8, the
follow_~g c1djuslrnent is permitted~------------.-----c-c---:---
We1ghted Average Slope of Net Buildable Minimum Density Factor
Area(s) of.Sc.ite:c.c._~-----+---
0%) -less thon 5% 85% !----------'~---'=~= -~~-~~~~---~---
5% -less tt1c.m 15%., 83'%, less 1 5% for each 1 % of average slope in
excess of 5%
L 15:;o -!ess than 40%:, 66%, less 2.0% for each 1 % of average slope in
excess of 15ll/o
-----·-----~---~~~.~'-'-~'-----
B. Weighted average slope shall be calc:ulatP.d as follows:
1 I Ile applicar1t shall submit a topographic survey of tile net huildable area(s) of the site which
identifies distinct areas within the following slope increments: 0-5%, 5-10%, 10-15(i'o, etc. up to 35-40%.
(King County D-?004)
21/\-108
!
D~VELOPMENT ST /\NDAROS -DESIGN REOUIREM[NTS 21A 14.170-21/\.14180
21A.14.170 Mobile home parks -Alternative design standards. /\s an cillernativc to lhc
building separation and internal slrect slanchrc1s of K.r: r: 21/\.14160·
A. Building sepciration requirements or setb,1cks betwet":n mobile homes and accessory
slrL.:cture~, 011 adjc.1cent spc.ices mc:1y he mod·1fit:d, provided:
1 The cornrnon vval!s rncet the firt-: protectior1 standards set forth ir, the Uniform Buildinu Code
and the standards set forth in the Uniform Fire C:ode tor duplexes, rnultifam·11y and co11dom·111iurn
devRlopmerts, c1s applicable; and
2. Rental agreement clauses by-laws or other leqal me.chJn1sms ~-J1pulate rnaintenanr:e
responsibilities for structures, fences and yards;
B. Private streets rnc1y hr_) used with a minimum drivinq surfr1cc of 22 fP.et in \t.tidth, provided
1 I he streets comply 1n .?J!l other respects with the road st;indards;
L. All required parkinfJ is locah--;d off-street rind as specified in K.C.C. 21A.-14.1GUl; and
3. Such streets shall not.
,1 directly connect two or rnom poin1s of vehicular access to the park; or
b. serve over 100 dwelling units w11h1n the park (Ord. 10870 § 377. 19D3).
2·!A.14.180 On-site recreation -space required
/\ Residential dcve:oprnents of more thw1 four units in the UR and R-1 through R-48 ;;ones,
stand-alone townhrnisc devefoprnents in the NG Lone 011 propt:rty designated commercial outside of
center in the urban area of rnore than four ur11ts, and mixed-usP developments of more than fo11r units,
shall provide recre.sition space for leisure, play 2tnd sport activities as follows·
1 Residential subrlivrsion. trnm1houses and apartn1ents developed at a density of eighl units or
less pPr ;;.1cre -three hundrnd ninetv sqti;_m_: feet per unit;
2 Mobile home park -two htmdred sixty S(Jl!clre fetil per unit: anr1
3. Apnrtment, townhouses developed at a density of ~Jreater than eight units per c1cre, and
mlxl:d use
<1. Studio and or1c bedroorn -ninety squ~Jrc feet per unit;
b. Two bedrooms -one /lllmlred seventy square f(-;(:t per unit; and
c. Three or more bedrooms one hundred seven1y square feet per unit
B Recreation space shall be pbced in ~-i designated recreation space tract if part of a subdivision
!he 1ract shall be dcdiec1led to 8 homemvner's associr::1tior1 or other workable or~;mization acceptable to
1he director, to provlrle continued mzirntenance nf the recreal1on space tract consistent with K.C.C
21A.14.200.
C /\ny recreation space located outdoors that is not p;::irt of a storrn water tracl developed in
ciccordcmce with subsection F ot this section shall·
1. Be of a grade and surfdce su1tabic for recreation i.11provernents and h,we a maximum rirc1de
of five percent;
2. De on the site of the propot,cd development:
3 Be located in an ,irea where the lopograrhy, soils, hydrology and olher physical
c!13racteristics arc of such quality as to create cJ flat, dry. obstacle-frep space in a configuration which
allows for passive and active recreation:
4. Be centrally located with oood vlsit,i!ity of the site from roads and sidewalks;
5. Have no dirnensions less than thir1y feet, (except trail segments);
6. Be located in one designated area, unless the director determines that residents of lcirge
subdivisions. townhouses and apartment developments would be better served by multiple areas
developed with recre.1tion or plc:J.y facilities;
7. Have a street roadway or pmkinq area frontage along ten percent or more of the recreation
space perimeter, except trail segments, if the required outdoor recreation space exceeds five thousand
square feet and is located in a single detached or tmvnl10use subdivision;
3. Be accessible and convenient to all residents within the development; and
9. Be located adJacent to, and be ;iccessib!e by, trail or walkway to any existing or planned
municipal, county or reyional park, public open space or tmil system, which may be located on adjoining
property.
(Kinq Counly 9-2004)
21A~l23
\L.CC ZIA. l'f
21A H 180 LONING
U. lnJoor recreation areas may be credite::d towards the total recreation space requirement, if the
director determines that the areas are located, designed and improved in a manner that provides
recreational opportunities functionally equiv~ilent lo those recreational opportunities available outdoors For
senior citizen :::1ssisted housing, indoor recreation areas need not be functionally equivalent but may
include social <:Hecis, game and craft rooms, and other multi-purposP. entertainment and education areas.
E Play equipmenl or age appropriate facilities shall be provided within dedicated recreation
space areas according to thr, followin~ requirements:
1. For developments of five dwelling units or more, a tot !ot or children's play area, which
includes age appropriate pfay equipment and benches, shall be provided consistent wilh K.C.C.
21/\14190;
2. ror developments of five to twenty-five dwelliny units, one of the forlowing recreation facilities
shall be provided in addition lo the tot lot or children's play ,irea·
a p!aygrourid equipment;
b sport cou:t
c sport field;
d tennis court; or
c. any other recreation facility proposed by the applicant and approved by the director.
3 ~or developrllents of twenty-six to fifty dwelling units, at least two ur more of the recreation
facilities listed in subsection E.L of this section shall be provided in addition to 1he tot Jot or children's play
area;
4. For developments of more than fifty dwelling units, one or more of the recreation facilities
listed in subsection E.2 of this section shall also be provided for every twenty-five dwell!ng units in addition
to the tot lot or children's play area. If calculations result in a fr3c\ion, 1he fraction shall !)e rounded to the
r,e3reE;1 whole number as follows:
a. Fractions of 0.50 or above shall be rounded up; and
b. Fractions below O.SO shall be rounded clown.
F. In subdivisions, recreation cucas that are contained within the on-site stormwc·iter tracts. but
are located outside of the one hundred year design water surface, rnay be credited for up to fifty percent of
the required square footage of the on-site recreation space reqtiirement on a foot-per-foot basis, subject
to the following criteria:
1. The stormwcJter tract and any on-site recreation tract shall be contiquously localed. At final
plat recording, contiguous stormwatcr and recreation lrocts shall be recorded as one tract and dedicated
to the horncowner's association or other organization as approved by the director:
2. The storm water facilities shall be constructed to meet the followinq conditions:
a. The side slope of the stormwatcr facilities shall not exceed thirty-three percent unless slopes
are existing, natural and covered with vegetation;
b A bypass system or an emergency overflow pathway shc1II be designed to handle flow
exceeding the facility desi9n and located so that it does not pass through active recreation arcc1s or
present a safety hazard:
c. The stormwater facilities shall be landscaped and developed for passive recreation
opportunities such as trails, picnic ~ircas and aesthetic viewing; and
d The stormwater facilities shall be designed so they do not require fencing pursuant to the
Surface \1"1./atcr Design Manual.
G. For of joint use of the tract for stormwater facilities and recreation space, King County is
responsible for maintenance of the stormwater facHities only and requires c1 drainage easement for that
purpose.
H /\ recreation space plan shall be submitted to the department and mv1ewed and approved with
engineering plans.
1. The recreation space plans shall address all portions of the site that will be used to meet
recreation space requirements of this section, including storrnwater facilities. The plans shall show
dimensions. finished grade, equipment, landscaping and improvements, as required by the director, to
demonstrate that the requirements of the on-site recreation space in K.C.C. 21 A.14.180 ond play areas in
K.C.C. 21A.14.190 have been met.
2. If engineering plans indicate that the on-site stormwater facilities or storrnwater tract must be
increased in size from that shown in preliminary approvals, the recreation plans musl show how the
required minimum recreation space under K.C.C. 21/\.14.180A will be met. (Ord. 14429 § 4, 2002: Ord.
14045 § 31, 2001: Ord. 12527 § 7, 1996: Ord.11978 § 13, 1995: Ord. 11621 § 48, 1994: Ord. 10870 §
378, 1993).
(King County 9-2004)
21A-124
I
DEV~LOPMENT STANDARDS DESIGN REQUIREM[NTS 21AM.185 · 21A14.20D
21A.14.185 Recreation space -fees in lieu of.
/\ The creation of on-site recreation spJce shall be the preferred method of providing new
development with oppor11rnitics for leisure. play and sports ilctivities. Applicants shall lo tile best of their
ability endeavor to provide recreation space on the project site_ However, if on-site recreation space is
not provided in accordance w,lh KC C. 21A14180, the applicant shall pay a fee-,n-1:eu of actual
recreation sp0ce if approved by King Crnmty_ King County c1cceptance of a fee-·,n-lieu payment is
discretionary. A feP.-in-Jicu of on-site recreation space may be permitted if the recrec1tion space provided
within a county park in thR vicinity will be of greater benefit to the prospective residents of the
development
D. Fef!s shall be determined annu,1ily by the department of parks and recreation on the :iasis of
the projected market value of the required recreation space land area after development. Any recreational
space provided by the appliecrnt shall be credited toward the required fees.
C If recreation space credit is applied to storrnwatGr facihtics in accordance with K.CC
21A14_180E, the devdoprncnt loses its option to request a fee-in-lieu and the remciinder of the required
recreation space and play area rnust be provided on site (Orel. 14045 § 32, 2001: Ord. 11621 § 49,
1994).
21A.14.190 On-site recreation -play areas required.
A. All single detached subdivisions, c1partment, townhouse and mixed-use developments, of more
than four units in the UR and R-4 through R-48 zones nnd sland-alone townhouse developments in the
NB zone of more than four units on property designated commercial outside of center ln the urban area,
excluding age-restricted senior citizen housing, shall provide children play areas within 1he recre;:ition
space on-s·11e, except if focilities are available to the public lk:1t meet all of the following:
1. Developed as a county, municipal or regional p;:irk;
2_ Locc1ted within one qu;:irter mile walking d·1stance; and
3. Accessible without crossing any artP.riaJ street.
1::3_ Play area designs shc:1!1:
1. Provide at lec-ist forty fivP. square feet per dwelling unit, with a minimum size of four hundred
square feet;
2. [3e adjacent to main pedestrian paths or near building entrances;
3 Meet the requirements of K.C.C. 21/\.14.180, and
4 Provide play equipment that meets, cJt a minimum, the Consumer Product Safoty Stand;irds
for equipment, soft suriacifly and spacing. (Ord. 14045 § 33, 2001: Ord. 13022 § 20, 1998: Ord. 10870 §
379, 1993)
21A.14.195 On-site recreation -financial guarantees for construction. Financial guc1rantees
for construction of recreation facilities required under K.C.C. 21A.14.180 and 71A 14.190 shall be
provided consistent with K.C.C Title 27A. (Ord. 14045 § 35. 2001)
21A.14.200 On-site recreation -maintenance of recreation space or dedication.
A. Recreation space that meets the criteria in K.C.C. 21/\. 14.180.C may, at lhe discretion of the
department of parks and recreation, be dedicated as a park open to the public in lieu of providing the on-
site recreation required under K.C.C. 21A.14.180 if the following criteria are met:
1. The dedicated 3rea is at least ten acres in size, unless when adjacent to an existing or
planned county park;
2. The dedicated l,md provides one or more of the following:
a_ shoreline access;
b_ regional tratl linkages;
c. habitat linkages;
d. recreation facilities; or
e. heritage sites; and
3. The dedicated area Is located within one mile of the project site.
B. Unless the recre3tion space is dedicated to King County in accordance with subsection A of
this section, maintenance of any recrer.1tion space retained in private ownership shall be the responsibility
of the owner or other separate entity capable of long-term maintenance and operation in a manner
acceptable lo the parks department. (Ord. 14045 § 34, 2001. Ord. 13022 § 21. 1998: Ord. 10870 § 380.
1993).
(King County 9-2004)
DEVELOPMENT STANDARDS -DESIGN REOUIREMENTS 21A14.210 71A.14.220
f' Only recyclable materials generated on-site shall be collected and stored at such collection
points. Except for initial sorting of recyc1bles by users. a!t other processing of such materials sholl be
conducted off-site.
F. The director rnay waive or rnod1fy specific storage space and collection point requirements set
forth in this section if the director finds. in '·Nflting, th.-1t an alternate recyding proqram design proposed by
the applicant meets the needs of the development and provides an equivalent or belier level of storage
arHI col\ect1on for recyclables (Ord. 12461 § 1, 1996 Ord. 10870 § 381. 1993)
21A.14.220 Fences. Fences are permitted as follows:
A. Fences exceeding 3 l1t~ight of six feet shall comply with the applicable street and lriterior
setbacks of the zone 1n which the property 1s located, except;
1 Fences located on a rockery. retaining wall, or berm within a required setback area are
permitted subject to the following requirements;
a. In R-1 through R-18, UR, RA and the resource zones·
( 1) The total height of the fence and the rockery. rctrnning wall or berrn upon which the fence
is located shall not exceed a height of ten feel. This height shall be measured from the top of the fence to
the ground on the low side of the rockery, retaining w:;ill or berm; ond
(2) The total height of the fence itself, measured from the top of the fence lo the top of the
rockery, retaining wall or berm, shall not exceed six feet
b In the R-24, R-48 and commercial/industrial zones. the height of the fence. measured from
the top of the fence to the top of the rockery, retaining wall or berm, shall not exceed six feet.
c. Any portion of the fence above a height of eight feet, measured to include both the fence
and the rockery, retaining wall, or berm (as described in a1. above}, shall be an open~work fence.
B. Fence:; locc1tecl on o rockery, retain·1ng wall or berm outside required setback areas shall not
exceed the building height for· the 7om\ measured in accordance with the .sf;i.ndards established in the
King County Building Code, Title 16.
RETAINING WALL WITH FENCE IN SETBACK
open-work fence·
H
C. Electric fences shall:
H max. 10' in R1 -R18, UR, RA
& Resource Zones
H1 max. 6' in all Zones
H 2 max. 8' for wall & solid-work
fence in all Zones
1. Be permitted in all zones. provided that when placed within R-4 through R-48 zones,
additional fencing or other barriers shall be constructed to prevent inadvertent contact with the electric
fence from abutting property;
2. Comply with the following requirements:
a. An electric fence using an interrupted flow of current at intervals of about one second on and
two seconds off shall be limited to 2,000 volts at 17 milliamp;
b. An electric fence using continuous current shall be limited to 1,500 volts at seven milliamp;
c. All P.!ectric fences in the R-4 through R-48 zones shal! be posted with permanent signs a
minimum of 36 square inches in area at 50 foot inlervcJls stating that the fence is electrified; and
d. Electric fences sold as a complete and assembled unit can be installed by an owner if !he
controlling elements of the installation are certified by an A.N.S.I. approved testing agency; and
(King County 9-2004)
21A-127
21A14.220-21A14.260 ZONING
D. Except as specifically required for the necessary securily related to a nonresidential use, no
barbed or razor-wire fence shall be located in any R-4 throuyh R48 zone (Ord 12987 § 5, 1998: Ord
11621 §50, 1994 10870§ 382, 1993)
21A.14.225 Hazardous liquid and gas transmission pipelines.
A. Tracts and easements containing hazardous liquid and qas transmissiofl pipelines and
required setbacks from such pipelines may include the following uses, subject to other regulations
applicable to each use and approval of the holder of the easement: utility structures not normally occupied
necessary for the operation of the pipeline, landscaping, trails, open space, keeping of animals,
agriculture, forestry, commercial signage, minor communication facilitiP-s and the utility structures not
normally occupied necessary for the operation of the minor commurncation facility, and other comrat!ble
uses as specified on the face of the recorded plat or short plat; provided that structures designed for
human occupancy shall never be a!!owed within pipeline tracts, easements or setbacks.
B. Hazardous liquid and gas transmission pipelines shall not be located in aquifer recharge
areas, landslide hazard areas or erosion hazi-3.rd areas_ When it is Impractical to avoid such areas, special
engineering precautions should be taken to protect public health, safety and welfare. (Ord. 14045 § 30,
2001 ).
21A.14.230 Trail corridors • Applicability. Trail easements shall be provided by any
development, except for single detached residential permits, when such developments are located within
any community or regional trail corridor identified by ~m adopted King County Functional Plan or
Community Plan identifying community and/or regional trail systems. The residents or tenants of the
development shal! be provided access to the trail easement. The area of the trail easement shall be
counted as part of the site for purposes of density and floor area calculations. (Ord. 10870 § 383, 1993).
21A.14.240 Trail corridors • Design standards. Trail design shall be reviewed by the
depr1rtment of deve!oprnent and environmental services for consistency with adopted standards for:
A Width of the trail corridor;
B. Location of the trail corridor on the sitA;
C Surtacing Improvements; and
D. Use(s) permitted within the corridor. (Ord. 11621 § 51, 1994: Ord.10870 § 384, 1993).
21A.14.250 Trail corridors -Maintenance of trail corridors/improvements. Maintenance of
any trail corridor or improvements, retainf:ld in private ownership, shall be the responsibility of the owner or
other separate entity capable of long-term maintenance and operation in a manner acceptable to the
parks division. (Ord. 10870 § 385, 1993).
21A.14.260 Wildlife habitat corridors -applicability. Habitat corridors shall be set aside and
protected along the designated wildlife habitat network adopted by the King County Comprehensive Plan
as follows:
A. Wildlife habitat corridors shall apply to the following development activities on parcels which
include a portion of a designated wildlife habitat corridor:
1 _ All urban planned developments, fully contr1incd communities, subdivisions, · short
subdivisions and binding site pl3ns;
2. All building permits on individual lots created prior to January 1, 1995.
B. Habitat corridors shall be identified and protected in one of the following ways:
1. Urban planned developments, fully contained communities, binding site plans, subdivisions and
· short subdivisions shall either place the corridor in a contiguous permanent open-space tract with all
developable lots sited on the remaining portion of the project site, or shall design the lots so that conservation
easements on individual lots can form a contiguous easement covering the corridor.
2. Individual lots shall place the corridor in a conservation easement.
C. All tracts or conservation easements shall be configured to meet the design standards in K.C.C.
21A14.270. (Ord. 13694 § 90, 1999 Ord. 11621 § 52, 1994).
(King County 9-2004)
21A-128
21/\.16.030 -21/11fi 040 ZONING
D. Institutional development refers lo those uses listed in:
1. KC.C 71/1.08 040 as cultural tJses. except arboretums;
2_ K.C.C. 21A.08.050 as churches, synagogues and temples, health services and education
serJices except specialized instruction schools permitted as an accessory use; and
3 KC C. 21A08 060 as goverrirnent services;
E. Utility development refers to those uses listed in K.C.C. 21 A 08.060 as utility facilities; ,rnd
F Uses ,n K C.C chapter 21A08 that are not listed in subsections A through E. of this section shall
not be subject to landscaping and tree retention requirements except as specified in any applicable review of
a conditional tN, or special use permits. (15032 § 21, 2004: Ord. 14045 § 44, 2001: Ord. 11671 § 54,
1994 11354§ 1.1994 Ord.11210§3, 1994: Ord 10870§388, 1993)
21 A.16.040 Landscaping -Screen types and description. The three types of landscaping
screens are described and applied as follows:
A Type I landscaping screen:
1 Type I landscaping is a "full screen" that functions as a visual barrier. This landscaping is
typically found adjacent to freeways and bet\Neen residential c:md non-rcslCiential areas.
,. Type I landscaping shall minimally consist of:
a. A mix of primarily evergreen trees and shrubs generally interspersed throughout the landscape
strip and spaced to form a continuous screen;
b. Beti.veen 70 and 90 percent evergreen trees;
c. Trees provided at the rate of one per 10 linear feet of tandscape strip and spaced no more than
30 feet apart on center;
d. Everyreer1 shrubs provided at the rate of one per linear four feet of landscape strip and spaced
no more than 8 feet apcJrt on center; and
e. Ground cover pursuant to K.C.C. 21A16.090;
B. Type 11 lcmdscaping screen:
1. Type II l;c1ndscaping is a "filtered sc~ccn" that functions as a visual separator_ This landscapinq
is typically found between commercial and industrial uses; between differing types of residential
development; and to screen industrial uses frorn the street; ~ z,i'\. f '--
2. Type II landscaping shall minimally consist of:
a. A mix of P-vergreen and deciduous trees and shrubs generally interspersed throughout thE LJt-N~,,.sc.,
lcJndscape strip spaced to create a filtered screen;
b At least 50 percent deciduous trees and at least 30 percent evergreen trees;
c. Trees provided at the rate of one per 20 linear feet of landscape strip and spaced no more than
30 feet apar1 on center;
d. Shrubs provided at the rate of one per four linear feet of landscape strip and spaced no more
than eight feet apart on center; and
e. Ground cover pursuant to K.C.C. 21 A. HWUO; tle,c
C. Type Ill landsCclping screen:
1. Type HI landscaping is a "see-through screen" that functions as a partial visual separator to Goff"'-(,
soften the appearance of parking areas and building elevations. This landscaping is typically found along
street frontage or between apartment developments;
2. Type Ill landscaping shall minimally consist of:
zi. A mix of evergreen and deciduous trees generally interspersed throughout the landscape strip
and spaced to create a continuous canopy;
b. At least 70 percent deciduous trees;
c. I rees provided at the rnte of one per linear 25 feel of landscape strip and sraced no more than
30 feet apart on center;
d. Shrubs provided at the rate of one per four linear feet of landscape strip and spaced no more
than 3 feet apart on center; and
e GroundcoverpursuanttoK.C.C.21A.16.090. (Ord.11621 §55, 1994: Ord.11210§4, 1994·
Ord. 10870 § 389, 1993).
(King County 9-2004)
21A-138
DEVFLOPMENT STAND/\RllS -LANDSCAPING AND WATFR USE 21A 16 050-'./11\.16 070
21A.16.050 Landscaping -street frontages. The average width of perimeter landscaping along
street frontages shall be provided as follows.
A. Twenty feet of Type II landscaping shall be provided for an instittJtional use, excluding
play(Jrounds and playfields;
B Ten feel of Type II landscaping shall be provided for an industrial development;
C. Ten feet of I ype II landscaping shall be provided for an above-ground utility facilities,
development, excluding distribtifion and !rans mission corridors. located outside a public right-of-way;
D Ten feet of Type Ill landscaping shall be provided for a commercicJI or attached/group residence
development; anci
streets:
E. For single f,m1Jly subdivisions and short subdivisions:
1 Trees shall be planted al !he rate of one tree for every forty feet of frontage along all public
2. T/1e trees sl1cili be·
a. Located withiri the street right-of-way 'if permi1tcd by the custodial state or local aqency;
b No more than twenty feet from the street right-of-way line if localed within a lot;
c. Maintained by the adjacent landowner unless part of a county maintenance program; and
d. A species approved by the county if loccited within the street right-of way and compatible with
overhead utility lines
3. The trees may be spaced at irregular intervals to accommodate sight distance requirements for
driveways and 1nlerscctions (Ord. 1404b § 45, 2001: Ord. 11621 § b6, 1994: Ord. 11210 § 5, 1994: Ord
10870 § 390, 1993).
21A.16.060 Landscaping -Interior lot lines. The average wrdth of perimeter landscap·1ng along
interior lot lines shc..111 be provided as follows:
A Twenty feet of Type I iandscaping shall be iflcluded in a comi'nercial or industrial development
c1long any portion r:idjacent lo a residential development;
B. Five feet of Type II landscaping shall be 1ncruded in an ;::ittached/group residence development,
except that along portions of the development adjacent to property developed with single detached
residences or ·,acant property !hat is zoned RA, UR or R(1 8), !he requirement shall be ten feet of Type II
landscaping;
C. Ten feel of Type I! landscaping shall be included in an industrial development along ;=rny por1ion
adjacent to a commerci;::il or institutional developmP.n!; and
D Ten feet of Type II landscaping shall be included in an institutional use. excluding ·[of
playgrounds and playfields, or an above-s:-;round utility facility development, excJuding] distribution or
tr.msmission corridors, when located outside a public right of-way. (Ord. 11939 § 1, 19%: Ord. 1121 O § 6,
1994 Ord 10870 § 391, 1993).
21A.16.070 Landscaping -surface parking areas. P3rking area landscaping shall be provided
within suliace parkin9 areas with ten or more parking stalls for the purpose of improving air quality, reducing
surf.ice water runoff, provldinq shade and diminishing the visual impacts of large paved areas as follows:
A. Residential devcJopments with common parking areas shall provide planting areas at the rate of
twenty square feet per parking stall;
B. Commercial, industrial or institutional developments shall provide landscaping at a rate of"
1. Twenty square feet per parking stall if ten to thirty parking stalls are provided; and
2 Twenty-five square feet per parking stall if thirty-one or more parking stalls are provided;
C. Trees shall be provided and distributed throughout the parking area at a rate of;
(King County 9-2004)
2111--139
21A16.070 -21A 16 085 LONING
1. One tree for every three parking stalls for a commercial or industrial development: and
2_ One tree for every five parking stalls for residential or institutional deve!opment:
D. The maximum distance between any pa,klrig stall and landscaping shall be no more than one
hundred feet;
E Permanent curbs or structural barriers shall be provided to protect the plantings from vehicle
overhang:
F. Landscaping around the perimeter of a site that is in addition to the perimeter landscaping
required by KC C. 21A.16.050 may count toward ten percent of the required surface parking area
landscaping if it 1s adjacent to the parking area: and
G. Parking area landscziping shall consist of:
1. Canopy-type deciduous trees, evergreen trees, evergreen shrubs and ground covers planted in
islands or strips;
7 Shrubs that do not exceed a maintained height of forty-two inches;
3. Plantings contained in planting islands or strips havfng an area of al least one hundred square
feet and with a narrow dimension of no less tkm five feet;
4. Ground cover in accordance with K.C.C 21A16.090; and
5. At least seventy percent of trees are deciduous (Ord. 14045 § 46, 2001: Ord. 11210 § 7, 1994:
Ord. 10870 § 397, 1993)
21A.16.080 Landscaping -Adjacent to freeway rights-of-way.
A Ail residential developments shall provide a minimum average width of 20 feet of Type I
landscaping ddjacent to freeway rights-of-way.
B All other developments shall provide a minimum average width of 20 feet of Type Ill landscaping
adjacent to freeway rights-of-way (Ord. 11210 § 8, 1994: Ord 10870 § 393, 1993).
21A.16.085 Landscaping -General standards for all landscape areas_ All new landscape areas
proposed for a development shall be s11b1ect to the following provisions:
or
A Berms shall not exceed a slope of two horizontal feet to one vertical foot (?.:1 ).
B. Al! new t11rf areas, except all-weather, sand-based athletic fields skill:
1. 13e 3ugmentcd with a two-inch layer of organic material cultivated a minimum of six inches deep,
2. Have an organic content of five percent or morP. to a depth of six inches as shown in a soil
sample analysis. The soil analysis shall include·
a. Deterrrnnation of soil texture, indicatinq percentage of organic matter,
b. An approximated soil infillration rate (either rm~asured or derived from soil/texture /infiltration
rate tables). A mnge of infiltration rates sldl be noted where appropriate, and
c. Measure Ph value.
C. Exc:epi as specifically outlined for turf areas in subsection B, the organic content of soils in any
landscape area shall be as necessary to provide adequate nutrient and moisture-retention levels for the
establishment of plantings.
D. Landscape areas, except turf or areas of establrshcd groundcover, shall be covered with at least
two inches of mulch to minimize evaporation.
E. Plants having similar water use characteristics shaH be grouped together in distinct hydrozones.
F. Plant selection shall consider adaptability to climatic, geologic, and topographical conditions of the
site. Preservation of existing vegetation is encouraged. (Ord. 11210 § 9, 1994).
(King County 9 2004)
21A-140
DEVELOPMEN I STANDARDS -LANDSCAPING AND WATER USF 21A 16090-21A16.100
21A16.090 Landscaping -Additional standards for required landscape areas. In addition to
the general standards of K.C.C. 21A16 085, landscape areas required pursuant to K.CC 21A16.050
through .080 shall conform lo the following st;,ndards:
A. All µ!ants shall conform lo American Association of Nurserymen (/\AN) qracfos and stand;,nJs as
published in the "American Standard for Nursery Stock" manual, provided that existing healthy vegetation
used to augment new plantings ;:;hall not be reqt1ired to meet the standards of this manual;
8. Single-stemmed trees required pursuant to this chapter sha!I at the time of planting conform to
the following standards:
1. In parking area landscapinq and in street rights-of-way:
a. Deciduous trees shall have a rnirnmum caliper of 1.75 inches and a he\ght of 10 feet, and
b. Coniferous and broadleaf evergreens shall be at least five feet in hei,1hl
2. In all other required Jandsr;apc areas:
a. Deciduous trees shall have c1 minim urn Cdliper of 1.[) inches rmd a height of ten feet, and
b_ Coniferous and broadlcc1f evergreen trees stla/1 Le at feast five feet in height.
C. Multiple-stemmed trees shall be permitted as an option to singJe-i:=.tcrnrned trees provided that
such multiple-stemmed trees are:
1. At least six feel in hc1ghl, and
2. Not allowed within street rights-of-way;
D. When the width of any landscape s!rip is 20 feet or yreater, the requ:red trees shatl be stagqemd
in two or more rows;
E. Shrubs shall be
1 _ At least an AAN con!ainer class #2 si?c at tirne of planting in Type ll, Ill and parkinq area
landscaping,
2. At lens! 24 inches "in height c=it the time of planting for Typt~ I landscaping. and
3_ Mr1intalned at a heigt1t not exceeding 42 Inches when located in Type Ill or p.1rking area
landscapin~J;
F. Ground covers shall be planted and spaced to result in total coverage of the majority of the
required landscape area within three years
G_ All fences shall be pl.-:1ccd on the inward side of ;:my required perimeter l,,mdscaping along the
slreet frontage.
H. Required street landsc~1ping may be placed within Kin~ County street ri~Jhts-of-way subject to 1he
County Road Design Standards, provided adequate space is maintained nlonu !he street l"lne to replant the
required landscaping should subsequent street Improvements require the removnl of landscaping within the
rights-of-way;
I Required street landscaping may be placed vvithin Washington St<1tc rights-of-way subject to
permission of the Wclshington State Department of Transportation
J. New landscape material provided within areas of undisturbed veget,1t1on or within the protected
area of significant trees shall give preference to utilizing indigenous plant species. (Ord. 11621 § 57, 1994:
11210 § 10, 1994: Ord. 10870 § 394, 1993).
21A.16,100 Landscaping -Alternative options. The following alternative landscape options may
be allowed, subject to counly approval, only if they accomplisl1 equal or better levels of screening, or when
existing cond'1tions on or adjacent to the site, such as significant topographic differences, vegetation,
structures or utilities would render aµpfication of this chapter ineffective or result in scenic view obstruction:
A The amount of required landscape area may be reduced to ensure that the total area for required
landscaping, and/or the area remaining undisturbed for the purpose of wfldfife habitat or corridors does not
exceed 15 percent of the net developable area of the site For the purpose of this subsection, the net
dcvelopable area of the site shall not include areas deemed unb1.iildable due to their location within sensitive
areas and any associated buffers.
B. The average width of the perimeter landsc;ipe strip may be reduced up to 25 percent along any
portion where:
1. Berms c1t !east three feet in height or architectural barriers at least six feet in height are
incorporated into the landscape design; or
::?. The landscape materials are incorporated elsewhere on-site:
(King County 9-2004)
21A-141
71/\1o 100 -21A 16 300 ZONING
C. In pedestri~rn district overlays, street perimeter landscaptng may be waived provided a site plan,
consistent with the applicable adopted area /Oninq document, is approved that provides street trees c1nd
0H1P.r pcdes1ri.:m-relc1tPd amenities;
D. Landsec1ring standards for uses located in a rural town or rural business centers designated by
the comprehensive plan may be waived or modified by the director if deemed necessary to maintain the
historic character of the area. Where a loc;1I or subarea plan with design guidelines has been adopted, the
director sha/1 base the landscaping modifications on the policies and guidelines of such plan
[. When an existing slnH_:ture precludes installation of the total amount of required sile perimeter
landscaping, such landscaping material shall be im:.orporated on another portion of the site.
F. Sinule-stemmed deciduous tree species that cr1nnot generally be planted and estabf"lshed in
larger sizes mc1y have a caliper of Jess than 1.5 inches; and
G. The number of trees and shrubs to be provided in required perimeter and parking c..1rca
landscapinq rnay be reduced up to 25 percent when a development uses landscaping materials consistino of
srecies typically associated with the Puget Sound Basin in the following proportions:
1. Seventy-five percent of groundcover and shrubs, and
2 Fifty percent of trees.
H. The dep21imer1t shall. pursuaflt to KC.C. 2.98, develop and maintain an advisory listing of trees
recommended for new plantings. Such list shall describe their general characteristics and suitability, and
provide guidelines for their inclusion within required landscape areas. (Ord 11621 § 58, 1994: Ord. ·11255 §
3, 1994: Ord. 11210 § 11. 1994 Ord. 10870 § 395, 1993).
C. An affidavit s:gned by an individual specified in subsection B. certifying that the landscaping has
been installed coflsistent with the approved landscaping plan, shall be submitted to the department within JO
days of installation completion, tmlcss the installed landscaping has been inspected and accepted by the
department.
0. The required landscaping shall be installed no later than three months after issuance of a
certificate of occtipancy for the project or project phase. However, the tirnP-limit tor compliance may be
extended to allow installation of such required landscaping during the next appropriate pl3nting season. A
financial 9uarantcc shall be required prior to issuance of the certificate of occupancy, if landscaping is not
installed and i11spected prior lo occupancy. (Ord. 11939 § 2. 199G: Ord. 11210 § 12, 1994).
21A 16.180 Maintenance.
/\. All landscapi11g shall be maintai11ed for the life of the pro1ect
B. /\IJ landscape materials shall be pruned and trimmed as necess.=iry to maintain a healthy growing
condition or to prevent primary limb failure;
C. With the exception of dead, dis;eased or damaged trees specifically retained to provide wildlife
habit;:it, olher dead. diseased, damaged or stolen plantings shall be replaced within three months or during
the next p13ntlng season if the loss does not occur in a planting season; and
D. Landscape areas shall be kept free of trash. (Ord. 11255 § 2. 1994: Ord. 10870 § 403. 1993).
21A.16.190 Financial guarantees. Financial guarantees shall be required consistent with the
provisions of Title 27 A. This time period may be extended to one year by the director, if necessary to cover a
planting and growing season. (Ord 12020 § 52, 1895 Ord. 11210 § 13. 1994: Ord. 10870 § 404, 1993).
21A16.300 Water use -Applicability of water budget for landscape areas. Irrigation systems of
any type are optional components of a landscape area. However, a water budget for Irrigation purposes shall
be established for all new development, except for:
A Individually platted single dwelling (attached or detached) residential lots, provided that
developer-Installed landscaping in common areas of residential projects is not exempt; and
B. Any project with a total landscaped area less than 500 s~uare feet (Ord. 11250 § 14, 1994 ).
(King County 9-2004)
21/1--142
21A.18030 70NINCi
21A.18.030 Computation of required off-street parking spaces.
A Fxcept as modified in KC.C. 21A.18.070B-D. off street parkinQ arr,as sh.all contain at a minimum
the number of parking spaces as stipulated in t11e following table. Off-street parking ratios expressed as
number of spctces per square feet means the usable or net square footage of floor area, exclusive of nor1--
public areas. Non-public areas include but are not limited to buildinu ma:ntenance areas, storage areas,
closets or restrooms. If the formula for determining the number of off-street parking spaces rP,su!ts in a
fraction, the number of off-street parking spaces shall be rounded to Hie nemest whole number with fractions
of .50 or grec1ter rounding up and fractions below .50 rounding dowr1.
---~-------· -l MINIMUM PARKING SPACE LAND USE
REQUIRED --
s
RESIDENTIAL (K.C.C. 21A.08.030A):
-----s----·
---
Single ddBchedff_ownhouse 2 0 per dwelling unit
Apartment:
Studio units 1 2 per dwelling unit
One bedroom units 1 5 per dwelling unit
Two bedroom units
r
1. 7 per dwelling unit
Thr~e bedroom units or larger 2.0 per dwelling unit ~-
Mobile home park 2_0 ~er dwell~ng unit f----------~
Senior citizen assisted 1 per 2 dwelling or sleeping u nits
Community residential facilities 1 per two bcdroo_ms_· __ .
Dormitory, including religious 1 per two bedrooms
Hotel/Motel including organizational I per bedroom
hotel/lodging ------
Bed and breakfast guest11ousc 1 per guest room, plus 2 per f acllity
---·
RECREATION/CULTURAL (K.C.C. 21A.08.040A):
Recreation/culture uses: ·--------··
Exceptions:
Bowling center --
Golf course
Tennis Club
~
Golf driving range
Park/playficld
Theater ------~--
Conference center
L ---_, ___ ------
(King County 9-2004)
-
1 per 300 square feet
----------j
5 per lane
3 per hole. plus 1 per 300 square feet of
club house facilities ----
4 per tennis court p!us 1 pe r 300 sq11.irc
feet of clubhouse facility
1 per lee
(director)
1_per_:l_ fixed seats
1 per 3 fixed seats, plus 1 per 50 square
feet used for assembly purposes without
fixed seats, or 1 per bedroom, whichever
.L: _results in the gre8ter number of spaces. ---------~--
21A-150
DEVELOPMENT STANDARDS -PARKING AND CIRCULATION 21A18.030
~ I LAND USE MINIMUM PARKING SPACES REQUIRED
GENERAL SERVICES (K.c,c. 21A.08.050A): ---
C:icnerol servir:r.s uses: 1 per_ 300 square foot
Exceptions· ----~
Funeml homc/Crem2tmy 1 per 50 ~quare feet _of chapel arec:i
Daycare J 2 per facility -~
~-
Oaycc:1re II 2 per h_~r.itity, plus 1 space for_each 20 children
Churches, synaqogue. temple I per 5 fixed sec1ts, plus 1 per 50 square feP.t of
gross floor area without fixed seab used for
f---
assembly purposes
--
Outpatient and Veterinmy 1 per :JOO squore feet of office, Jabs and
clinic offices examination rooms
~-
Nursin9 and personal care 1 per 4 beds
facilities -
Hospilc.11 1 per bed --
Elementary schools 1 per classroom, plus 1 per 50 stude'.'ts_
Secondary schools
Middle/junior high schools_ 1 per classroom: e_lus ·t per_ 50 students
High schools -1 per _classroo~_,_p~us 1 per 1 O student.s
High schools with slmliums greater of 1 per clc1ssroorn plus I per 10
students, er 1 per 3 fixed seats in st_adium --
Vocat1onc1I scl10ols 1 pr:r classroo'!!_,_ plu:::; 1 per five studc~ts
~-
Specialized instnJC:tion 1 per c:Jassroom, plus 1 pRr two students
schools
Artist Sttidios .9 per 1,000 square feet of area u:::;ed for
sturlios
GOVERNMENT/BUSINESS SERVICES (K.C.C. 21A.08.060A): -
----
GovemmenUbusincss Sf:'rv!ces uses: 1 pr:r 300 square feet -
Ex~ptions: _______ -
Public agency ymd 1 per 300 squ;-ire feet of offices, plus .9 per
1,000 square.:, feet of indoor storage or repair
areas
Public: ;::iuency nrchives 4 per 1000 square feet of storage i:irea, plus ·1
per 50 square feet of waiting/reviewing areas
Courts 3 per courtroom, plus 1 per 50 square feet of
fixed seat or_ ?_ssernbly areas --
Police faci!)~_ (direclor)
Fire facility (director)
Construction nnd trade 1 per 300 square feet of office, plus 1 per 3,000
~-square feet of storage area
Warehousin~J and storage 1 per 300 square feet of orfice, plus .9 per 1,000
square feet of storage area
Self-service storage 1 per 3,500 square feet of stornge area, plus 2 -for any resident director's unit
Outdoor advertising services 1 per 300 square feet of office, plus .9 per 1,000
s11uare feet of storage ar~_a
H0c:1vy equipment repair 1 per 300 square feet of office, µJus .9 per 1,000
~----square fe~(!f lndo(?r repair arnas
----
Office ----------_, 1 per 300 square feet
(King County 9-2004)
21A-151
21A18 030 ZONING
LAND USE I MINIMUM PARKING SPACES
REQUIRED
RETAIL/WHOLESALE (K.C.C. 21A.08.070A):
Retail trade uses: 1 per 300 square feet
Exceptions· -
Food stores, less than 3 plus 1 per 350 square feet
~
15,000 square feet
Gasoline SP.rvice st3tion::=. 3 per facility, plus 1 per service bay
w/o grocery
Gasoline service stations 1 per facility, plus 1 per 300 square feet of
w/grocery, no service bays store ~-.
Restaurants 1 per 75 square feet in dining or lounge
areas
Whoiesale trade uses .9 per 1000 square feet
Retail and wholesale trade mixed use 1 per 300 square feet
...
MANUFACTURING (K.C.C. 21A.08.080A):
Manufacturing uses .9 per 1,000 square feet .
Winery/Brewery .9 per 1,000 square feet, plus 1 per 50
square feet of tc1sting cirea
RESOURCES (K.C.C. 21A.08.090A):
..
Resource 1iscs (director) ·-
REGIONAL (K.C.C. 21A.08.100A):
f-----~
Regional uses ( director) .•.
R. An applrcant may request a mod1f1cat1on of the m1n1mum required number of parking spaces by
providing that parking demand can be met with a reduced parkir1y requirement. In such cases, the director
mc1y approve a reduction of up to fifty percent of the minimum required number of spaces.
C. When the county has received ;-i shell building permit application, off-street parking requirements
shall be based on the possible tenant improvements or uses authorized by the zone designation and
compatible with the limitations of the shell permit. When the range of possible uses result in different parking
requirements, the director will establish the amount of parking based on a likely mnge of uses.
D. Where other provisions of this code stipulate maximum parking allowed or reduced minimum
parking requirements, those provisions shall apply.
E. In any development required to provide six or more parking spaces, bicycle parking shall be
provided. Bicycle parking shall be bike rack or locker-type parking facilities unless otherwise specified.
1. Off-street parking areas shall contain at least one bicycle parking space for every twelve spaces
required for motor vehicles except as follows:
a. The director may reduce bike rack parking facilities for patrons when it ,s demonstrated that
bicycle activity will not occur at that location.
b. The director may requfre additional spaces when it is determined that the use or its location will
generate a high volume of bicycle activity. Such a determination will include but not be limited to the following
uses:
( 1) Park/playfield,
(2) Marina,
(King County 9-2004)
21A-152
Dcc\/ELOPMENT STANDARDS-PARKING AND CIRCULATION
(3) Ubrary/museumlarboretum,
(4) Elm1entar;/sccondary school,
(5) Sports club, or
21A 18.030-21A18050
(6) Retail business (when located along a developed bicycle trail or designated bicycle roule).
2. Bicycle facilities for patrons shall be located within 100 feet of lhe building entrance and shall be
designed to aJJow either ci bicycle frame or wheels to be locked to a structure attc:iched to the paw~ment
3 All bicycle parking and slorage shall be located in safe, visible areas thal do not impede
pedestrian or vehicle trc1ffic flow, and shall be well !1! for nighttime use.
4. VVhcn more than ten people are employed on site, enclosed locker-type parking facifities for
employees shall be provided. The director sh,:ill allocate the required number of parking spar:es bc1ween
bike rack parking and enclosed locker-type parking facilities.
5. One indoor bicycle storage space shaJ/ be provided for every two d1.velling units in townhouse
and apartment residential uses, unless individual garages are rrovtded for every unit The director rnay
reduce the numt)P.r of bike rack parking spnces if indoor storage facilities are available to alt residents (Ord.
13022 § 22, 1998 Ord. 11978 § 14, 1995: Ord. 11157 § 18, 1993 Ord. 10870 § 407, 1993).
21A.18.040 Shared parking requirements. The amount of off-street parkiny required by K.C.C.
211\ 18.030 may be reduced by an amount determined by lhe director when shared parking facilities for two
or rnore uses are proposed, provided:
A The total parking area exceeds 5,000 square feet;
8. Tf1c parking facilities are designed and developed as a single on-·site common parking facility, or
as a system of on-site and off-site f3ci!1ties, if all facilities are connected wilh improved pedestrian focllitfes
;-md no buildin!::] or use involved is more than eight hundred_feet from thf: rnost remote ~,hared facility;
C. The amount of the reduction shall not exceed ten percent for each use, unless:
1. The normal hours of operation for each use are separated by c:1t least one hour; or
2_ A parking demand study is prepared by a profcss·1or1al traffic engineer .=ind submitted by the
applicant documenting that the hours of actual parking demand tor the proposed u:-;P.s will not conflict and
those uses will be se[\/ed by adequale parking if shared parking reductions are authori?ed;
3. The director will determine the amount of reduction .subject to paragmph D of this section.
D. The total number of parking spaces in the common parking facility is not less than the minimum
required spc1ces for any single use;
F. A covenant or other contract for shared parking between the cooperating property owners is
approved by the director_ This covenant or contract must be recorded with King County records and
elections division as a deed restriction on both properties and wnnot be modified or revoked without the
consent of the director; and
F_ If any requirements for shared parking are violated. the affected property owners must provide a
remedy satisfactory to the director or provide the full amount of required off-street parking for each use, In
accordance with the requirements of this chapter, unless a satisfactory alternative remedy is approved by the
director. (Ord. 11621 § 60, 1994: Ord 10870 § 408, 1993).
21A.18.050 Exceptions for community residential facilities (CRF) and senior citizen assisted
housing.
A. The minimum requirement of one off-street parking space per two bedrooms for CRF's and one
off street parking space per two senior citizen assisted housing units may be reduced by up to 50 percent, as
determined by the director based on the following considemtions:
1. Availability of private, convenient transportation services to meet the needs of the CRF
residents;
2.Accessibility to and frequency of public transportation; and
3. Pedestrian access to health, medical, and shopping facilities;
B. If a CRF facility or senior citizen assisted housing is no longer used for such -purposes, additional
off-street parking spaces shall be required in compliance with this chapter prior to the issuance of a new
certificate of occupancy. (Ord. 10870 § 409, 1993)
(King County 9-2004)
ENVIRONMENT /\LL Y SENSITIVE /\REAS 21 /\ 24
Sections:
21A24 010
21A24 020
21/\24.030
21A24 040
21A24.ll50
21A.24 060
21/\.24.070
21/\.24.075
21/\.24.080
21A24 090
21A.24100
21A.24.110
21/\.24.120
21/\.24.130
21/\.24.140
21A24150
21A.24.160
21/\.24.170
21A.24 180
21/\24.190
21 A.2·1200
21 A.24 21 O
21A.24 2?0
21/\.24.230
21/\.24.240
21 A.24 2oU
21/\24.260
21/\.24.270
21A24.275
21A.24.28U
21 A.24.290
21 A.2>1.300
21/\24.310
21A.24.320
21/\.24.330
21/\.24.340
21/\.24.345
21A.24.350
21A24 360
21A.24.370
21/\.24.380
21/\.24.390
21/\.24.400
21/\.24410
21A.24.420
21A.24 500
21/\.24.510
Chapter 21A.24
ENVIRONMENTALLY SENSITIVE AREAS
Purpose.
Applicability
Appculs
Sensitive areas rules_
Complete exemptions
l'ar1ial exemptions
Exceptions
rvtodification or waiver of sensitive area requirements -urban lots
Sensitive area rnaps c:md inventories.
Disclosure by applicant
Sensitive area review
Sensitive area special study requirement.
Contents of sensitive area special study.
Mitigation, maintenance. monitoring and contingency.
Financial guarantees.
Vegetation management plan.
Sensitive area markers and signs.
Notice on title.
Sensitive area tracts and designations on site plans
Alteration.
Building setbacks.
Coal mine hazard areas: Deve!oprnent standards and permitted nlterations.
Erosion hazard areas: DevelDpment standards and permitted alterations.
Flood hazard areas: Comronents
Flood fri119e: Devefopment standards and permitted alterations.
Zero-rise floodway. Development standards and permitted alterations.
FEMA floodway: Development standards and permitted alterations.
Flood hazard areas: Certific,3tion by engineer or surveyor.
Channel relocation and stream meander areas.
Landslide hazard areas: Development standards and permitted alterations.
Seismic hazard areas: Development standards and permitted alterations.
\/o!c.=mic hazard areas: Development standards and permitted alterations.
Steep slope hazard areas: Development standards and permitted alterations.
Wetlands: Development standards.
Wetlands: Permitted alterations.
Wetlands: mitigaHon requirements.
Wetlands: Mitigation bankinq.
Wetlands: Limited exemption.
Streams: Development standards.
Streams: Permitted alterations
Streams: Mitigation requirements.
Sensilive areas mitigation fee -Creation of fund.
Sensitive areas mitigation fee -Source of funds.
Sensitive areas mltigation fee -Use of funds.
Sensiti\•e areas mitigation fee -Jnvestment of funds.
Sensitive area designation.
Effect of approval of septic system design based on sensitive area designation.
(King County 9-2004)
21/\-183
ENVIRONMENTALLY SENSITIVE AREAS 21A2,1.010 -21A24 020
21A.24.010 Purpose. The purpose of this chapter is to implemenl the goals ,md policies of lhe
Washington State Environmenlal Policy Act RCW 43.21C, and the Kinr1 County Comprehensive Plan
wtiicti call for protection of the natural environment and the public health and safety by:
A_ Establishing development standards to protect defined sensitive areas;
B. Protecting rnernbers of the public and public resources and facilities from injury, loss of life,
property damage or finar1d,.il loss due to flooding, erosion, avalc1nche, landslides, seismic and voiccu1ic
events. soil subsidence or steep slope failures;
C. Protecting unique, frc.Jgile and valuable elements of the environment indudi119, but not limited to,
wildlife and its habitat:
D Rcquiri11g mitigation of unavoidable impacts on environmentally sensilive ,.:ireas by regulating
alterations in or near sensitive areJs;
E. Preventing cumulatJve adverse environmental impm:ts on water avai!3bili1y, 'Na1cr q1Jality, ground
water, wetlands and streams;
F. Measuring the quantity and quality of wetland and s1rP-arn resources 3nd preventing overall net
loss of weliand and stream functions;
G. Protcctinq the public trust as to navigable Welters and c1quatic resources;
H. Meeting the requirements of the National Flood Insurance Program and main1aining Kinu County
as an eligible community for federal flood insurance benefits;
I. Alerting members of the public including, bu\ no\ limited to, appraisers, owners, potenlial buyers or
!essees to the development limitations of sensitive areas; and
J. Providing counly officials with sufficient information to protect sensitive cJreas. (Ord. 11621 § 69,
1[)9,1: 10870 § 448, 1993).
21A.24.020 Applicability.
A The provisions of this chapter shall apply lo all land 1Jses in King County, and all persons within
the county shai! corn ply with the requirements of this chapter.
B. King County shall not approve ,my permit or otherwise issue any authorization to alter the
condition of any land, water or vegetation or to construct or alter any structure or improvement without first
assuring compliance with the requirements of this chapter.
C. Approv3J of a development proposal pursuant to the provisions of this chapter does not discharge
the obligation of the applicant lo comply wiU1 the provisions of this cha pier.
D. When any provision of any olher chapler of the King County Code connicts wiH, \his chapter or
when the provisions of this chapter are in conflict, thaJ provision which provides more protection to
environmentally sensitive areas shall apply unless specifically provided othcrvvise in this chapter or unless
such provisiori. conflicts with federal or state laws or regulations.
E. The provisions of \his chapler shall apply to all forest practices over which the county has
jurisdiction pursuant to RCW 76 09 and WAC 222. (Ord. 10870 § 449, 1993).
(King County 9-2004)
21A-185
21A24 030 -21A.24.050 ZONING
21A.24.030 Appeals. Any decision to approve. condition or deny a r!P.velopment proposal based on
the requirements of K C.C. 21 A24 may be appealed according to and as part of the appP.al procedure for the
permit or approval involved (Ord. 10870 § 450, 1993).
21A.24.040 Sensitive areas rules. Applicable departments within King County are authorized to
adopt, pursuant to K_C.C. 2.98, such administrative rules and regulations as are necessary and appropriate
to implement K.C.C 21A.2'1-and to prepare and require the use of such forms as are necessary to its
administration. (Ord. 10870 § ~51. 1993).
21A.24.D50 Complete exemptions. The followin9 are exempt from the prov1s1ons of this chapter
and a11y administrative rules promulgated thereunder:
A. Alterations in response to emergencies which threaten the public health, safety and welfare or
\Nhich pose an imrnirient risk of damage to private property as long as any alteration undertaken pursuant to
this subsection is reported to the department immediately The director shall confirm that an emergency
exists and determine wtwt, 1f any, mitigation shall be required to protect the health, safety, welfare and
environment and to repair any resource damage;
B. A~Jricultura! activities as described below, in existence before November 27, 1990, and performed
not less often than once every five years thereafter:
1 Mowing of hay, gmss or qrain crops;
2. Tilling. discing, planting, seeding, harvesting, soil preparation, crop rotation and related activities
for pasture, food crops, grass sePd or sod if such activities do not take place on .steep slopes;
3_ Norm.11 and routine maintenance of existing irrigation and drainage ditches not used by
salmonids;
4. Norrnr"ll c1nd routine maintenance of farm ponds, fish ponds, manure lc1goons and livestock
wc1tering ponds; and
ti. grazing by livestock_
C. Public water, electric and natuml gas distribution, public sewer collection, cable communications.
telephone utility rind related activities undertaken pursuant to county-approved best rnc:magernent practices,
as follows:
1 Normal and routine maintenance or repair of existing utility structures or rights-of-way;
2_ Relocation of electric facilities, lines, equipment or appurtenances, not including substations,
with an associated volta~e of fifty five thousand volts or Jess, only when required by a focal govemmental
i:lgcncy which r:!pproves the new location of the facilities;
3. Replacement, operation, repair, modification, installation or construction in existing developed
utility corridors. an improved county road right-of-way or county-authorized private roadway of all electric
facilities, lines, equipment or appurtenances, not including substations;
4. Relocation of public sewer local collection, public water local distribution, natural gas, cable
communication or telephone facilities, lines, pipes, mains, equipment or appurtenances, only when required
by a local governmental agency which approves the new location of the facilities;
5. Replacement, operation, repair, modification, installation or construction of public sewer local
collection, public waler local distribution, natural gas, cable communication or telephone facilities, lines. pipes,
mains, equipment or appurtenances when such facilities are located within an improved public right-of-way
or county authorized private roadway;
D_ Maintenance, operation, repair, modification or replacement of publicly improved roadways as
long as any such altcrntion does not involve the expansion of roadways or related improvements into previ-
ously unimproved rights-of-way or portions of rights-of-way;
E. Maintenance, operation or repair of publicly improved recreation areas as long as any such
alteration Joes not involve the expansion of improvements into previously unimproved recreation areas;
F. Public agency development proposals only to the extent of any construction contract awarded
before November 27. 1990. provided that any lilw or regulation in effect at the time of such award shall apply
to the proposal;
(King County 9-2004)
21A-186
ENVIRONMENT /\LL Y SENSITIVE AREAS 21/\24.050 -21/\24 060
G. All clearing and grading activities which are exempt from the requirement for a clearing and
grading perm ii as specified i11 K.C C 16 82 050, unless these activities require other permits or
authorizatiorrs as specified in KC C 21/\24.020.
H The following exempt activities are permitted in coar rnine hazard areas, provided that the
applicable landowner, operntor or utility ls made c1ware of potc.ntra/ hazards:
1. Forest practices;
2. Agricultural activities;
3_ Minin~J activities;
4. Power. tefcphone. and cabie television utility lines;
5. Grading, fiHing, stockpile removal, and reclamation activities performed in conjunction with or
by the Department of Interior's Office of Surface Mining, Reclamation and Enforcement with the intent of
eliminrlting or mitigating threats to human health, pubfic safety, environmental restoration or protection of
property; and
6. Land uses and activities that existed prior to November 30, 1998. (Ord 13319 § 6, 1998:
Ord. 11621 § 71, 1994 10870 § 452, 1993).
21A.24.060 Partial exemptions.
A. The fol!ow!nq arc exempt from the provisions of this chapter and any administrative rules
promulgated !hereunder, except for the notrce on title provisions, KCC 21A24.170 -21A24.180, and lire
flood hazard area provisions, K.C C 21 A ?4 ?30 -21 A 24 270:
1. Structural modification of. addition to or replacement of structures, except single detached
residences, in existence before November ?7, 1900 ·Nhich do not meet the building setback or buffer
requirements for wetlands, streams or steep slop8 ha1arrl areas if the modification, addition, rcplacemenl or
related activity does not increase the existlnq footprint of the structure lying within the above-described
bufJding setback c1rec1 scnsiiive area or buffer; c: 1£. \
2. Structural rnodlfication of, addition to or replacement of single detached residences in existence
before November 27, 1990 which do not meet the building setback or buffer requirements for wetlands,
stre;,.ms or steep slope hazard areas if the modification, addif1on, replacement or related activity does not
increase the existing footprint of the residence !y!ng within the above-described buffer or building setback
c1rea by more than 1000 sqtiarc feet over that existing before November 27. 1990 and no portion of the
rnodifiec-1tion, addition or replacement is located doser to the sensitive area or, if the existing residence is in
lhe sensitive area, extends faril1er into the sensitive--: vrt:~a: and
3. Mainten.incc or repair of structures which do not meet tile development shmc:ards of th:s
chapter for coal mine, hmd.sl1de, seismic or volcanic hazard r1reas if the maintenance or repair does not
increase the footprint of the s1ructure and \here is no increased risk to life or property as a result of the
proposed maintenance or repair;
B_ The grazing of livestock is exempt from the provisions of this chapter ..:ind any administrative rules
promulgated thereunder, except for the livestock restriction provisions, K.C.C. 21A.24.320 and 21 A 24.360,
and any animal density limitations established by law, if the grazing activity was in existence before
November 27, 1990;
C. A permit or approval sought as pan of a development proposal for which multiple permits are
required is exempt from the provisions of this chapter and any administrative rules promulgated thereunder,
except for the notice on title provisions, KC.C 21A.24. 170 -21A.24. 180, if:
1. King County previously reviewed al! sensitive areas on the site;
2_ There is no material change in the development proposal since the prior review;
3 -r here is no new ir1forrnation available which is important to any sensitive area review of the site
or particular sensitive area;
4. The permit or approval under which the prior review was conducted has not expired or, if no
expiration date, no more than five years lapsed since the issuance of that permit or approval; and
5. The prior permit or approval. mcluding any condilrons, has been complied with. (Ord. 10870 §
453, 1993).
(King County 9-2004)
21A-187
21A.24.070 · ?1A?4 075 ZONING
21A.24.070 Exceptions.
A If the application of this chapter woold prohibit a development proposal by a public agency and
urnity, the agency or utility may apply for an exception pur.su;:rnf to this subsection:
1. The public agency or utility shall apply to the department and shall make available to the
department other related project documents such as permit applications to other agencies, special studies
and SEP/\ documents.
2. The department shall review the application based on the follmving criteria:
a. there is no other practical nlternative to the proposed development with less impact on the
sensitive area; and
b. the proposal minimizes the impact on sensitive areas.
3. The department shall process exceptions, provide public notice, and provide opportunity for the
public to request a ptiblic hearinq, and provide an appeal process consistent with the provisions of K.C.C.
20.20.
4. This exception shal! not allow the use of the following sensitive areas for regional storrnwater
management facilities except where there is a clear showing that thP. facility will protect public hea!tt1 and
safety or repair damaged natural resources:
a. class 1 streams or buffers;
b. class 1 wetlands or buffers with plant associations of infrequent occurrence; or
c. class 1 or 2 wetlands or buffers which provide critical or outstanding habitat for herons, raptors
or stc:Jle or federal designated endangered or threatened species unless clearly demonstrated by the
applicant that there will be no impact on such habit.at.
B. If the application of this chapter would ceny all reasonable use of the property, the applicant may
apply for an exception pursuant to this subsection:
1. The applicant may apply for a reasonable use exception without first having appliP-d for a
vmi;:mce if the requested exception includes relief from standards for which a variance cannot be granted
pursu,mt to the provisions of K.C.C. chapter 21A.44. The applicant shall apply to the department, and the
department shall make a final decisinn based on the following criteria:
a. the application of this chapter would deny all reasonable use of the property;
b_ there is no other reasonable use with less impact on the sensitive area;
c the proposed development does not pose an unreasonable threat to the public health, safety or
welfare on or off the developmenl proposal site and is consistent with the general purposes of this chapter
and the public ir1tcrest; and
d. any alterations permitted to the sensitive area shall be the minimum necessary to allow for
rc~asonable use of the property; and any authorized alteration of a sensitive area under this subsection shall
be subject fo conditions established by the department including, but no! rirnited to, mitigation under an
approved mitigation plan. (Ord. 13190 § 19, 1993: Ord. 12196 § 54, 1996: Ord. 11621 § 73, 1994: Ord.
10870 § 454, 1993).
21A.24.075 Modification or waiver of sensitive area requirements --urban lots. The
purpose of this secti0n is to provide an alternative to the variance, and exception processes for minor
development. A furth~\ purpose of this section is to minimize impacts to sensitive areas by allowing minor
modifications of the zo~ng code which allow single family residences on existing, legal urban lots without
requiring a variance or exception. The director shall have the discretion to modify or waive some or all of
the requirements of this~1tle, including mitigation requirements, pertaining to class 3 wetlands, class 3
streams, and their associ ted buffers or building setbc1ck r1reas in accordance with the provisions of this
section.
A An applicant may\fequest a modification or waiver of sensitive ~rea requirements pursuant to this
section provided the lot or lotS\are located in an urban area designated in the King County Comprehensive
Plan and 1
' B. The applicant for t~'e modification or waiver of sensitive area requirements shall submit any
sensitive area special studies follo\,ving a preappiication review meeting as required under K.C.C. 21A24.110
as well as such other documents, studies, as requested by the director.
(King County 9-2004)
21A-188
ENVIRONMENT /\I I Y SFNSITIVE AktcAS 21A24 075 -21A24 090
C. The Cirector rn3y grar1t a rnodiflcat1on or waiver of sensitive area requirements provided:
1. The propos;il is the minimum necessary to accommodate the building footprint and access. In
no case. however, shall the building footpr:nt exceed 5000 square feet, including access.
2. Access i~, located so as to hcwe the least impact on the sensitive area and Its buffer,
3. The propos<:11 preserves the functions and values of ~vetlands ;:md streams to the maximum
extent possible,
4. Adverse 1rnpacts resulting from alterations of steep slopes are minimized,
5. The~ proposal includes on-site mitigation lo tt1c maximum extent possible,
6. ThP-proposal will not significantly affect drainage capabilities, flood potenti31, amt steep slopes
and landslide h;-vards e1tl1er on neighboring properties or on the proposal itself; and
7_ The proposal first develops nonsensitive area land, then the sensitive area· buffer before the
sensitive area itself is developed.
The director rnay require on-site or off-site mitigation measures to compensate for the loss of the
functions and values of the sensitive areas and may impose rnitigatin~ condi_ti6ns to the modification or
waivPr in order to meet the standards of this subsection C. /
D. Where a modification or waiver of sensitive area requirements upder this section is proposed. U1e
director shall give writtAn mailed notice of the proposed modification o//waiver to a!I owners of property
located within three hundred feel of any boundary of the subject prope~y'and lo the water and land resources
division and shall allow fifteen calendm days for comment before _making a decision. The dP.cision of t11e
director regarding the modification or waiver shall be mailed lo /the app!icant and to any other person who
requests a copy. The decision shall state the reasons for denial,or any required mitigntion or other conditions
imposed. The decision of the director regarding the modifitation or waiver may be appealed per K.C.C.
211\24.030.
E. This section shall not 3pply to the following steep ~;/ope hazard areas:
1. Steep slope ~1azard areas that are unrnitigatable landslide hazard areas; and
2. Steep slope hazard areas of slope greater than sevenly percent where ei1her the lo! or slope are
abutting and above a class 1 or 2 wetland stream, ;md associated buffer, or an open storrnwater conveyance
syslern_ (Ord. 13190 § 20, 1998 Ord 11621 § 70, 1994)
21A.24.080 Sensitive area maps a_nd inventories.
A The distribution of many envfr(?rimenta/ly sensitive areas in western King County is displayed on
maps in the Sensitive Areas lv13p Folio. Many of the wetbnds are inventoried and rated and that inform3tion
is published in the King County Wetlr1f)ds Inventory Notebooks. Many flood hazard areas are mapped by the
Federal Insurance Administration in ,,a' scientific and enqincering report entitled "The Flood Insurance Study
for King County ... If there is a conf)fd among !he maps, inventory c:md sitc-speClfic features, the depr.1rtment
of development and envlronmer/al services shall verify the actual presence or absence of the features
defined in this title as sensitive ;lreas. The determination rn,iy be challenged by the property owner. (Ord
11621 § 74. 1994 Ord. 10870 § 455, 1993)
21A.24_090 Disclosure by applicant.
/\. The applicant shall disclose to King County the presence of sensitive areas on the development
proposal sile and any mapped or identifiable sensitive areas within 100 feet of the applicant's property
B. If the development proposal site contains or is within a sensitive area, the applicant shall submit
an affidavit which declares whether the applicant has knowledge of any illegal alteration to any or all sensitive
areas on the development proposal site and whether the applicant previously has been found In violation of
this chapter, pursuant to_ K.C.C. Title 23. If the applicant prcvlously has been found in violation, the applicant
shall declare whether such violation has been corrected to the satisfaction of King County. (Ord_ 10B70 §
456, 1993).
(King County 9-2004)
21A-189
211\24.1 oo -?rn 74.120 ZONING
21A.24.100 Sensitive area review.
A. Except as provided 1n s11bsectior1 C of U1is section, King County shall perform a sensitfve area
review for any development pro;)osal permit application or other request for permission to proceed with an
zi!teration on a sit(; that includes a sensitive area or is within an identified sensitive area buffer or building
setback area.
8. As part of tile ser1sitive rnea review, King County shall:
1 _ Determine whether any sensitive area exists on the property and confirm its nature and type;
7 Dctcrrrnne whether a sensitive area special study is required;
3 Evaluate the sensitive area special study:
4_ Determine whether the development proposal is consistent with this chapter;
5 Determine whether any proposed alteration to the sensitive area is necessary; and
6. Determine if the mitigation and monitoring plans and bonding measures proposed by the
applicant are suffrcient to protect the pubi1c health. safety and welfare. consistent with the goals, purposes,
objectives and requirements of this chapter
C. If a development proposal does not involve any site disturbance, clearing, or grading and only
requires a permit or ;::ipproval under K.C.C. chapter 16.04 or 17.04, sensitive area review is not required,
unless the develnrment proposal is located within a landslide hazard area, seismic hazard area, or coal mine
hazard area and the proposed development will cause additional loads on the foundation. such as by
expanding the habitable square foolr.tge of the structure or by adding or changing structural features th~-:1t
change the load bearing characteristics of the structure_ Sensitive area review required under H1is subsection
shall be limited to consideration of the development proposal and the hazard area 1n which it is !oc~atcd. (Ord.
14449 § 9. 2002 Ord. 10870 § 457, 1993)
21A.24.110 Sensitive area special study requirement.
A An applicant for a developrnRnt proposal which includes a sensitive area or is within an
identified sensitive area buffer shall submit a sensitive area special study to cu.icquately evaluate the proposal
and all probable impacts_
B. King County mc.1y vi1aive the requirement for a special study if the applicant shows, to King
County's satisfaction. that:
1. There will be no alteration of thP. sensitive area or buffer;
2_ l he development proposal will not have an impact on the sensitive area in a manner contrary to
the goals, purposes. objectives and requirements of this chapter; arid
3. The minimum standards required by this chnpter are met.
C If necessary to insure cornrliance with this chapter, King County rnay require additionul
information from the applicant, separate from the special study. (Ord. 10870 § 458, 1993)-
21A.24.120 Contents of sensitive area special study_
A. The sensitive area special study shall be in the form of a written report and shall contain the
following, as applicable·
1. Identification and characterization of all sensitive areas on or encompassing the development
proposal site;
2_ Assessment of the impacts of any alteration proposed for a sensitive area or buffer, assessment
of the impacts of any alteration on the development proposal, other properties and the environment, and/or
assessment of the impacts to the development proposal resulting from development in the sensitive area or
buffer;
3_ Studies which propose adequate mitigation, maintenance, monitoring and contingency plans
and bonding measures;
4 _ A scale map of the development proposal site; and
5. Detailed studies, a,; required by King County.
B. /\ sensitive area ~pecial study may be combined with any studies required by other laws and
regulations; and
C If the development proposal will affect only a part of the development proposal site, the county
may limit the scope of the required special study to include only that part of the site which may be affected by
the development. (Ord 10810 § 459, 1993).
(King County 9-2004)
21A-190
r.NVIRONMENTAI LY SFNSITIVI' /\RE!,S 21A24.130 -21/\24.170
21A.24.130 Mitigation, maintenance, monitoring and contingency.
I\ /\s determined by King County, mitigation, maintenance and monitoring measures shaH be in
place to protect scnsi1ive c1re;is ,-rnd buffers from alterations occurring on the development proposal site.
8. Wt1ere monitoring reve,1ls a siunificant deviation from predicted impacts or a failure of mitigation
or maintenance measure5, the applicant shG)l be responsible for appropriate corrective action which, when
approved, shall be subject to further rnonitor1119. (Ord 10870 § 460, 1993).
21A.24.140 Financial guarantees. Finc1nciaJ guarantees shall be required consistent with the
provisions of Title 27 A (Ord 12020 § 54, 1995: Ord. 10870 § 461, 1993).
21A.24.150 Vegetation management plan.
A For all developrnenl proposals where preservntion of existing vegetation is required by this
chapter, a vegetation management plan shall be submitted and approved prior to issuance of the permit or
other request for permi.sslon to proceed with cu, alteration
8-The veyetation management plan shall identify the proposed clearing \irnits for the project and
any areas where vegetation in c:i sensitive area or its buffer is proposed to be disturbed.
C Where clearing includes cutting any merchantable stand of timber, as defined in WAC 222~16-
010(28), lhe vegetation management plan shall include a description of proposed logging prnctices which
dernonstmtes how all sensitive areas will be protected in accordance with the provisions of this chapter.
D. Clearing limits as shown on the plan shall be marked in the field in a prominent ;:md durable
rnarmer. Proposed methods of field marking shall be reviewed and approved by King County prior to any site
alteration. Field marking st1all rcrnain in place until the certificate of occupancy or final project approval is
granted
E The vegetation management plan may be incorporated into a temporary erosion and sedirnent
control pl,:m or landscaping plan where either of these plans is required by other laws or regulc.ltions.
F. Submittal requirements for vegetation management plans shall lie set forth in adrninistmtive
rules (Ord 10870 § 462. 1993).
21A.24.160 Sensitive area markers and signs.
A. Permanent survey stakes delineating the boundary betvvcen adjoining property and sensitive area
tracts shall be set, using iron or concrete markers as established by current survey standards.
B. The boundary between a sensitive area tmct and contiyuous land shall be identified with
permanent srgns (Ord. "10870 § 463. 1993).
21A.24.170 Notice on title.
A. Except as othervvise provided in subsection of C of this section, lhe owner of any prop8~y
containing sensitive areas or buffers on which a development proposal is submitted sl1aU file a notice
approved by King County with the records, elections and licenslng services division. The required contents
and form of the notice shall be set forth in administrative rules. T tic notice shall inform the public of the
presence of sensitive areas or buffers on the property, of the application of this chapter to the property and
that llmitations on actions in or offccting such sensitive areas or buffers may exist. The notice shall run with
the land.
B. The applicant for a development proposal shall submit proof that the notice required by this
section has been filed for public record before King County shall approve any development proposal for the
property or, in the cc1se of subdivisions, short subdivisions and binding site plans, at or before recording.
C. The notice required under subsection A of this section is not required if:
1. The property is a public right-of-way or the site of a permanent public facility; or
2. The development proposal does not require sensitive area review under K.C.C. 21A.24.100C.
(Ord.14449§ 10, 2002 Ord.14187§3,2001: Ord.10870§464, 1993).
(King County 9-2004)
21/\-191
21A.24180 -21A.24 210 ZONING
21A.24.180 Sensitive area tracts and designations on site plans.
A. Sensitive area tracts shall be used to delinccitc and protect those sensitive areas and buffers
listed below in development proposals for subdivisions, short subdivisions or bindin~J site plans and shall be
recorded on all documents of title of record for all .Jffected lots:
1 All landslide hazard areas and buffers that arc one acre or greoter in size;
2_ All steep slope hazard areas and buffers that are one acre or yreater in size:
3 All wetlands and buffers; and
4. All streams and buffers.
B. Any required sensitive area tract sh;-~11 be held in an undivided interest by each owner of a building
Joi within the development with this ownership interest passing with the ownership of the lot or shall be held
by an incorporated horneowncr's association or other legal entity whlch assures the ownership, maintenance
,:md protection of the tract.
C Site plans submitted as part of development proposals for building permits, master plan
developments and clearing and gradinq permits shall include and delineate:
1. All fiood hazard areas, if they have been mapped by f-1::MA or King County or if a special study is
required;
2. Landslide, volcanic, coal mine and steep slow~ hazard areas;
3. Streams and wetlands;
4. Buffers; and
5. Building setbacks.
D. If only a part of the development site has been mapped pursuant to K.C.C. 21A?4 120C. the part
of the site that has not been mapped shall be clearly identified and labeled on the site plans. (Ord 14449 §
11, 2002 Ord. 10870 § 465, 1993)
21A.24.190 Alteration. Any human activity which results or ls likely lo result in an impact upon the
existing condition of a sensitive area Is an alteration which is subject to specific limitations as specified for
each sensitive area. Alterations include, but are not !irniterJ to, grading, filling, dredging, draining,
channelizing, applying herbicides or pesticides or any hazardous substance, discharging pollutants except
stormwater, grazing domestic animals, paving, constructing, applying gravel, modifying for surface water
management purposes. cutting, pruning, topping, trimming, relocating or removing vegetation or any other
human activity which results or is likely to result in an impact to existent ve~1etatior1, hydrotogy, wildlife or
wildlife habitat. Alterations do not include walking, fishing or any other passive recreation or other similar
activities. (Ord. 10870 § 466. 1993).
21A.24.200 Building setbacks. Unless otherwise provided, buildings and other structures shall be
set back a distance of 15 feet from the edges of all sensitive area buffers or from the edges of all sensitive
areas. if no buffers are required. The following may be allowed in the building setback area:
A Landscaping;
R. Uncovered decks;
and
C Building overhangs 1/ such overhangs do not extend more than 18 inches into the setback area;
D. Impervious ground surfaces, such as driveways ~md patios, provided that such improvements
may be subject to special drainage provisions specified in administrative rules adopted for the various
,, sensitive areas. (Ord. 10870 § 467, 1993).
21A.24.210 Coal mine hazard areas: Development standards and permitted alterations.
A. Alterations within coal mine hazard areas shall not be permitted without prior acceptance of a
coal mine hazard assessment report and provided that:
1. Based upon recommendations contained w1th1n the report, a studied site shall be classified as
one or a combination of the following:
a. declassified coal mine areas;
b. moderate coal mine hazard areas; or
c. severe coal mine hcFard areas.
(King Co11nty 9-2004)
21A-192
ENVIRONMEN I /\1.L Y SENS! JIVE /\REAS 21/\24.210
? ThP. cocil mine ha7c:1rd assessment report shall be prepared by a professional engineer using
methodology and assumptions consis!P.nt with stc1ndards or professional eng!neenng guidelines adopted by
the depmlmenl. The report may contain the following as determined by the department to be necessary for
the review of the proposed use-
a c.1 stc1ternent of the profess1ona! engineer's qualifiG1tions and lic:ensin9 information, togeiher
with a signature and stamµed seal;
b. a list of references utilized in preparation of the report;
c. a description of the analytical tools and processes that have been used 1n the report;
d. surface exploration data such 8s borings, drill holes. test pits, wells, geologic reports, and other
relevant reports or site investigations that rnay be useful in making conclusions or recommendations about
the site ur1der investigation;
e. a description of historical data and information used in the evaluation together with sources.
Such data and informatior. shall include:
(1) topographic maps ot a scale and contour interval of sufficient detail tn assess the site. The
site boundaries and proposed site development shall be overl;1iri with the rnine rlan view map, as
appropriate,
(2) copies of illustrative coal mlne maps showing remnant mine conditions, if avoil8ble:
(3) aerial photography, as appropriate;
(4) geological data including geologic crosssections and other illustr<ltive data as appropriate,
and
(5) available historic mine records indicating the dates of operation, the dale of cessation of
active mining, the number of years since abandonment, mining methods, shoring and timbering information,
the strength of the overlying rock strata, the extracted seam thickness, the dip or inclination of the strata,
workings and surface, the projected surface location of the seam outcrop or subcrop, the estimated depth of
;he seam outcrop or subcrop, if covered by glacial outwash, glacial till or other materials at depth, total coal
~onn::1ge produced, estimated coal mine by-product material produced and the estimc:1ted extraction ratio.
L a mine plan view rnap, reproduced at the same scale as the topographic map, showing the
locat:on of the mine, the extent of mining, the proposed site development. 1f applicable, and any remnant
abandoned mine surface features. The following shall be included:
(1) the layout of the underground mine;
(2) the location of any mine entries, portals, adits, mine shafts, air shafts, timber shafts, and
other significant mine features;
(3) the location of any known sinkholes, significant surface depressions, trough subsidence
features, coal mine spoil piles and other rnine-relnted surface features;
(4) the location of any prior site improvements that have been carried out to mitigate abandoned
coal mine features; and
(5) zones showing varying overburden-cover-to-seam-thickness ratios. when appropriate.
g. a statement as to the relative degree of accuracy and completeness of the maps and
information revie1Ned, especially regarding historic mine rnvp accuracy, cmd reasons why such sources are
considered reliable for the purpose of the haLard assessment report;
h. a mitigation plan containln9 recommendations for mitigation, as appropriate, for the specific
proposed alteration;
i recommendations for additional study, reports, development standards or architectural
recommendations for subsequent and more specific proposed alterations, as appropriate;
j. analysis and recommendations, if any, of the potential for future trough subsidence and special
mitigation; and
k. a delineation of coal mine hazard areas for the site under investigation using a map identifying
the specific category (i.e., severe, moderate, or declassified) of mine hazard area. For the purposes of
obtaining accurate legal descriptions, the mine hazard areas shall be surveyed and the survey map shall be
drawn at a scale of not Jess than 1"~200'.
(King County 9-2004)
21A24.210 ZONING
3. Giving great weight to tl1e licensing requirements of professional engineers and standards of
professional accountability and liability, the department shall review the coal mine hazard assessment report
and within the time period specified in K.C.C. 20.20.050 either accept the report, recommend revisions or
additions to the report or return the report to the applicant as unaccepted and detail the specific deficiencief;
In the event of a disagreement, the applicant m,,y submit the report to a mutually agreed-upon third party
professional engineer who will conduct the review and issue a decision binding upon the department and
applicant.
4. When a hazard assessment report has been accepted. the applicant .sh;:;i!I record a notice on the
title of the property as follows:
"NOTICE"
''This property is localed in an area of historic coal mine activity. A coal mine hcvard
assessment report has been prepc:Jred to chnracteri?e the potential hazards contaJned on this
property. l he report is dated [insert date of the final report], was prepared by [111sert name of
professional engineer with license number] at the direction of [insert name of property owne,j,
and reviewed by the King County department of development and environmental services
[and, if necessary, include name of peer reviewing professional engineer ~vith license
number]. A review of the report is advised prior to undertaking unregulated or exempt land
use activities and is required prior to undertakir1g regulc:1tcd land use activities."
B. Permitted a!terations within a coal mine haLard area are allowed as follows, subject to other King
County Code permit requirements:
1 Within declassified coal mlne area~ all alterations are permitted.
2. Within moderate coal mine hazard areas and coal mine by-product stockpiles, r1II alter.:itions are
permitted subject to a mitigation plan to minimize risk of structural damage using approµriate criteria to
evaluate the proposed use.
If required or recommended by the hazard assessment report, the mitigation plan to address
potential trough subsidence must be prepared by a professior1al engineer and may be included in the coal
mine hazard assessment report or may be an additional study or report, as appropriate.
3. \Nithin severe coal mine hazard areas the following alteratlons are permitted:
a. all grading, filling, stockpile removal, c:1nd reclamation activities undertaken pursuant to a coal
mine ha?ard assessment report with the intent of eliminating or mitigating threats to human health, public
safety, environmental restoration or protec!1on of property, provided that:
(1) signed c:md stamped plans have been prepared by a professional engineer;
(2) as-built drawings are prepared following reclamation activities; and
(3) the plans and as-built drawings shall be submitted to the department for inclusion with the
coal mine hazard assessment report prepared for the property.
b. private road construction and maintenance activities, provided that mitigation to eliminate or
mtnirnize significant risk of personal injury are incorporated into road construction or maintenance plans.
c. buildings with less than four thousand square feet of floor area that contain no living quarters
and that are not used as places of employment or public assembly, provided that mitigation to eliminate or
minimize significant risk of personal injury are incorporated into site, building, and/or landscaping plans.
d. additional land use activities provided that they are consistent with recommendations contained
within any mitigation plan required by the hazard assessment report. (Ord. 13319 § 7, 1998: Ord. 11896 § 1,
1995: Ord. 10870 § 468, 1993).
(King County 9-2004)
21A-194
ENVIRONMl=NT /1Ll.Y SENSITIVE ARE/\S 21A24 220 · 21A 24.230
21A.24.220 Erosion hazard areas: Development standards and permitted alterations.
A Clearing on an erosion hazard area is allowed only from April 1 to September 1, except that:
1. Up to 15,000 squcJre feet may be cleared on any lot. subject to any other requirement for
vegetation retention and subject to any clearing and grading permit required by K.C.C 16 82. and
2. Timber harvest may be allowed pursuant to an approved forest practice perrnit issued by the
Washington Department of Natural Resources.
B. A!I development proposals on sites containing erosion hal"ard areas shafl include a ternµorary
erosion control plan consistent with this section and other laws ;:rnd regulations prior to receiving approval
Specific requirements for such plans shall be set forth in administrative rnles
C. /\II .subdivisions, short subdivisions or binding site plc::ins on sites with erosion hazard areas shall
comply with the following additional requirements:
1. Except as provided in this section, existing vegetation shall be ret.1inerl on zill lots until building
permits are approved for development on individual lots;
2. If any vegetation on the lots is damaged or removed during constrnction of the subdivision
1nfrastruclure. the applicant shall be
required lo submit a restoration plan to King County for review and approval Following approval, the
applicant shall be required to implement the plan;
3. Clearing of vegetation on lots may be aliowed without a separate clearing and grading permit if
King County determines that
a. such clearing is c.1 necessary part of a large scale grading plan;
b. it is not feasible to perform such grciding on an individual lot basis; and
c. drainage from the gmded area will meet water quality standards lo be established by
administrative rules.
D. Vi/here Kino County determines thcJt erosion frorn a development site poses a significant risk of
damage to downstream receiving waters. based either on the size of the project, the proximity to thP-
receiving water or the sensitivity of the receiving water. the applicant shall be required to provide regular
monitoring of surface water discharrJe frorn lhe site If the project does not meet water quality standards
established by law or administrative rules, the county nwy suspend further development work on the site until
such standards are met.
E fhe use of hazardous substmiccs, pesticides and fertilizers in erosion hazard areas may be
prohibited hy King County (Ord. 10870 § 469, 1993).
21A.24.230 Flood hazard areas: Components.
A. A flood ha;.,-ard r1rea consists of the following components:
1. floodplain;
2. Flood fringe;
3. Zero-rise fioodway; and
4. Federal Emergency Management Agency ("FEMA") floodway.
B. King County shall determine the flood hazard area after obtaining, reviewing and utilizing base
nood elevations and available noodway data for a flood having a one percent chance of being equaled or
exceeded in any given year, often referred to as the "100-year flood." The base flood is determined for
existing conditions, unless a basin plan including projected flows under future developed conditions has been
completed and adopted by King County, in which case these future flow projections shall be used. In areas
where the Flood Insurance Study for King County includes detailed base flood calculations, those
calculations may be used until projections of future flows are completed and approved by King County. (Ord.
10870 § 470, 1993).
(King County 9-2004)
21A-195
21A24.240 ZONING
21A.24.240 Flood fringe: Development standards and permitted alterations. Development
proposals on sites within the fiood fringe area shall meel the following requirements:
/\. Development proposals shall not reduce lhe effective base fiood storage volume of the
fioodplain. Grading or other activity which would reduce the effective storage volume shall be mitigated by
creating compensatory storage on the site or off the site if legal arrangements can be made 10 assure that
the effective compensatory storage volume will be preserved over time. Grading for construction of livestock
m.1nure storage facilities to control non-point source water pollution designed to the standards of and
approved by the Kinq Conservation District is exempt from this compensatory storage requirement.
B. All elevated construction shall be designed c..md certified by a professional structural engineer
licensed by the State of Washington and shall be approved by King County prior to construction.
C. Subdivisions. short subdivisions and binding site plans shall rnoet the following requirements:
1. New building lots shall contain 5,000 square feet or more of buildable land outside the zero nse
fioodway, and building setback areas shall be shown on the face of the plat to restrict permanent structures
to this buildable area;
2. /\II utilities and facihties such as sewer, gas, electrical and water systems shall be located and
constructed consistent with subsections 0., E. and H;
3. Base flood data and fiood hazard notes shall be sl1own on the face of the recorded subdivision.
short subdivision or binding site plan including. but not limited to, the bc1sc flood elevation, required fiood
protection elevations and the boundaries of the floodplain and the zero.rise fioodway, if determined; and
4. The following notice shall also be shown on the face of the recorded subdivision. short
subdivision or binding site plan for all affected lots·
"NOTICE"
"Lots and structures located within flood hazard areas may be iriacccss1blc by emergency vehicles
during flood events. Residents and property owners should take appropriate advance precautions."
D. New residential structures and substantial improvements of existing residential slructures shall
meet the following requirements:
1. The lowest floor shall be elevated to the flood protection elevation;
2. Portions of ;::i structure which are below the lowest flour area shall not be fuHy enclosed. The
areas and rooms below the lowest floor shall be designed to automatically equalize hydrostatic and
hydrodynamic flood forces on exterior walls by allowing for the entry and exit of floodwaters. Designs for
satisfying this requirement shall meet or exceed the following requirements:
a. a minimum of two openings on opposite walls having a total open area of not less than one
square inch for every square foot of enc!oserl area subject to flooding shall be provided;
b. the bottom of all openings shall be no higher than one foot above grade; and
c. openings may be equipped with screens, louvers or other coverings or devices if they permit
the unrestricted entry and exit of floodwaters;
3. Materials and methods which are resistant to and minimize flood damage shall be used; and
4. All electrical, heating, ventilation, plumbing, air conditioning equipment and other utility and
service facilities shall be flood-proofed to or elevated above the fiood protection elevation.
E. New nonresidential structures and substantial improvements of existing nonresidential structures
shall meet the following requirements:
1. The elevation requirement for residential structures contained In subsection D.1 shall be met; or
2. The structure shall be fiood-proofed to the flood protection elevation and shall meet the following
requirements:
a. the applicant shall provide certification by a professional civil or structural engineer licensed by
the State of Washington that the fiood-proofing methods are adequate to withstand the flood-deptlis,
pressures, velocities, impacts, uplift forces and other factors associated with the base flood. After
construction, the engineer shall certify that the permitted work conforms with the approved plans and
specifications; and
(King County 9-2004)
21A-196
FNVIRONMENT/\LLY SENSITIVE AREAS 21/1.21210
b approved building permits for flood-proofed nonresidential structures sl1all contain a statement
notifying applicants !hot flood insurance premiums shall be based upon rc1tes for structures which are one
foot below the flood-proofed level;
3. Materials and methods which are resistant to and minimize flood damage shall be used; anrl
4. /\II electrical, heating, ventilation, plumbing, dir conditioning equipment arid other utility cmd
service facilities shall be flood-proofed to or elevated above the flood protection elevation.
r-.=. All new construction shall be anchored to prevent flotation, collapse or lateral movement of the
structure.
G. Mobile homes and mobile home parks shall meet the following requirements:
1. Mobile homes shall meet all requirements for flood hazard protection for residential structures.
shall be anchored and shall be installed using methods and practices which minimize flood damage; and
2. No permit or approval for the follow1nq shall be granted unless all mobile homes with111 Ille
mobile home park meet the requirements for flood hazard protection for residentral structures·
a. a new mobile home park;
b. an expansion of an existing mobile home park; or
c. ariy repair or reconstruction of streets, utilities or pads in an existin~J mobile home park whid1
equals or exceeds 50 percent of the value of such streets, utilities or pads.
H. Utilities shall meet the following requirements.
1. New and replacement utilities including, but not limited to, sewage treatment facilities shall be
flood-proofed to or elevated above the flood protection elevation;
2. New on--site scwaqe disposal systems shall be. to the extent possible, located outside the limits
of the base flood elevation. The installation of new on~site sewage disposal systems iri the flood fringe may
be allowed if no feasible alternative site is av21ilable:
3. Sewage and agricultur81 waste storage facilities shall be flood proofed to lhe flood protection
elevation;
4. Above-ground ut"11ity transmission Jines, other than elRctnc trc1nsmission lines, shatl only be
arlowed for the transport of non-hazardous substances; and
5. Buried utility transmission lines trm1sporting hazardous substances shall be buried at a minimum
depth of four feet below the maximum depth of scour for the base flood, as predicted by a professional civil
engineer licensed by the State of \/VcJshington, and shall achieve sufficient negative buoyancy so that any
potential for flotation or upward migration is eliminated.
I. Critical facilities may be allowed within the flood fringe of the floodplain, but only when no feasible
alternative site is available. Critical facilities shall be evaluated through the conditional or special use permit
process. Critical far-ilities constructe;d within the flood fringe shall have the lowP.st floor elevated to three or
more feet above the bc1se flood elevation. Flood-proofing and sealing measures shall be taken lo ensure that
hazardous substances will not be displaced by or released into floodwatP.rs
Access routes elevated to or above the base flood elevation shall be provided !o c1!1 critical facilities from
the nearest maintained public street or roadway.
J. Prior to approving any permit for alterations in the flood fringe, King County shall determine that
all permits required by stale or federal law have been obtained. (Ord. 11621 § 76, 1994: Ord. 10870 §
471, 1993).
(King County 9-2004)
21/1--197
21A24.250 ZONING
21A.24.250 Zero-rise floodway: Development standards and permitted alterations.
A The requirements which apply to the flood fringe shall also apply to the zero rise floodway. The
more restrictive requirements sha!I apply where there is a conflict.
B. A development proposal including, but not limited to, new or reconstructed structures shall not
cause any increase in the base flood elevation unless the following requirements are rnet:
1. Arnendrnents to the Flood Insurance Rate Map are adopted by FEMA, in accordance with 44
CFR 70, to incorporate the increase in the base flood elevation; and
2. Appropriate legal documents are prepared in which all property owr1ers affected by the
increcised flood elevations consent to thR impacts on their property. These documents shall be filcti with the
title of record for t11e affected properties
C. The following are presumed to produce no increase in base flood elevation and shall not require
a special study to establish this fact:
1. New residential structures outside the FEMA floodway on lots in existence before November 27,
1990 which contain !css than 5,000 square feet of buildable land outside the zero-nse floodway and which
have a total building footprint of all proposed structures on the lot of less than 2,000 square feet;
2. Substantial improvements of existing residential structures in the zero-rise floodway, but outside
the FEMA floodway, where the footprint is not increased; or
3 Substantial improvements of existing residential structures meeting the requin~ments for new
residential structures in K.C C 21A.24.240.
D. Post or piling construction techniques which permit water flow beneath a structure shall he used
E. All temporary structures or substances hazardous to public health, safety and welfare, except for
hazardous household substances or consumer products containing hazardous substances, shall be removed
from the zero-rise floodway during the flood season from September 30 to May 1.
F _ New residentiaf structures or any structure accessory to a residential use shall meet the following
requirements:
1. The structures shall be outside tf1e FEMA floodway: and
2. The structures shall be on lots in existence before November 27, 1990 which contain Jess than
5000 square feet of buildable land outside the zero-rise floodway.
G. Utilities mcJy be allowed within the zero-rise floodway if King County determines that no feasible
alternativP. site is available, subject to the following requirements:
1. Installation of new on-site sewage disposal systems shall be prohibited unfess a waiver is
grcrnted by the Seattle/King County department of public health; and
2_ Construction of sewage treatment facilities shall be prohibited.
H Critical facilities shall r1ol be allowed within the zero-rise floodway except as provided in
subsection J.
L Livestock manure storage facilities and associated non-point source water pollution facilities
designed, constructed and maintcJincd to the standards of and approved in a conservation plan by the Krng
County Conservation District may be allowed if King County reviews and approves the location and design of
the facililies
J. Structures and installations which are dependent upon the noodway may be located in the
floodway if the development proposal is approved by all agencies with jurisdiction. Such structures include,
but are not limited to:
1. Dams or diversions for water supply, flood control, hydroelectric
production, irrigation or fisheries enhancement;
2. Flood damage reduction facilities, such as levees and pumping stations;
3. Stream bank stabilization structures where no feasible alternative exists for protecting public or
private property;
4. Storm water conveyance facilities subject to the development standards for streams and
wetlcJnds and the Surface Water Desrgn Manual;
5. Boat launches and related recreation structures;
6. Bridge piers and abutments; and
7 Other fisheries enhancement or stream restoration projects. (Ord 10870 § 472, 1993).
(Krng County 9-2004)
21A--198
ENVIRONMENTALLY SENSITIVE AREAS 21A.24 260 -211\.24 280
21A.24.260 FEMA floodway: Development standards and permitted alterations.
!\. The requirements which apply to the zero-rise floodway shall also apply to the FEMA floodway
The rnore restrictive requirements shall apply where there is zi conflict.
B. A development proposal including. but not lirntlcd to, new or reconstructed structures shall not
cause any increase in the base flood elevation.
C. New residential or nonresidential structures are prohibited within lhe FEMA floodway.
D. Substantial improvements of existing residential structures in the FEMA Hoodway, meeting the
requirements of WAC '173-158-070, as amended. are presumed to produce no increase in base flood
elevation and shall not require a special study to establish this fact. (Ord 10870 § 473. 1993).
21A.24.270 Flood hazard areas: Certification by engineer or surveyor.
A. For all new structures or substantial improvements in a nood hazard area, the applicant shall
provide certification by a professional civil engineer or land surveyor licensed by the State of Washington of:
1. The actual as-built elevation of the lowest fioor, including basement: and
2. The actual as-built elevation to which the structure is flood-proofed, if applicable.
B. The engineer or surveyor shall indicate if the structure has a basement
C. King County shall maintain ttie certifications required by this ~ection for public Inspection. (Ord.
10870 § 474, 1993).
21A.24.275 Channel relocation and stream meander areas. No structme shall be allowed
which would be at risk due to channel relocation or stream meander until the promulgation of a public rule.
(Ord 11621 § 75, 1994).
21A.24.280 Landslide hazard areas: Development standards and permitted alterations. A
Jeveloprncnt proposal on a site containino a landslide hazard area shall meet the following requirements:
A. /\ minimum buffer of :>O feet stwll be established from all edges of the l.cmdslide hazard area_
J he buffer shall be extended as required lo rnitiyate a steep slope or erosion haz;ird or as otherwise
necessary to protect the public health, safety and welfare. For landslide hazard areas that are also steep
slopes over 700 feet in height, the builclin9 setback shall be 50 feet from the buffer The building setback
may be reduced to c:i rniriirnurn of 15 foet fr1:m the buffer if, hased on a special sturly, King County determines
that the reduction will adequately protec1 the proposed development and the sensitive area. For single family
residential buildin9 permits only, King County may waive the special study requirement and authorize building
setback reductions. pursuant to K.C.C. 21A.21 015 or if Kinq County determines that the reduction will
adequately protect the proposed development and the sensitive area;
B. Un\ess otherwise provided herein or c:1s part of an dpproved alteration, removal of any vegetation
from a landslide hazard area or buffer shall be prohibited, except for limited removal of vegetation necessary
for surveying purposes and for the removal of hazard trees determined to be unsafe according to tree
selection rules promulgated pursuant to this chapter Notice to King County shall be provided prior to any
vegetation removal permitted by this subsection;
C. Vegetation on slopes within a landslide hazard area or buffer which has been damaged by
human activity or infested by noxious weeds rnay be replaced with vegetation native to King County pursuant
to an enhancement plan approved by King County. The use of hazardous substances, pesticides and
fertilizers in landslide hazard areas and their buffers may be prohibited by King County; and
D. Alterations to landslide hazard areas and buffers may be allowed only as follows:
1. A landslide hazard area located on a slope 40% or steeper may be altered only if the alteration
meets the standards and !imitations set forth for steep slope hazard areas in K.C.C. 21A.24.310;
2. A landslide hazard area located on a slope less than 40% may be altered only if the altemtion
meets the following requrrements:
a. the development proposal will not decrease slope stability on contiguous properties; and
b. mitigation based on the best available engineering and geological practices is 1mplemenled
which either eliminates or minimizes the risk of damage, death or injury resulting from landslides; and
3. Neither buffers nor a sensitive area tract shall be required if the alteration meets the standards
of subsection D.2. (Ord. 12822 § 9. 1997: Ord. 10870 § 475, 1993).
(King County 9-2004)
21A-199
21A2,l290-21A.24.310 ZONING
21A.24.290 Seismic hazard areas: Development standards and penmitted alterations. A
development proposal on a site containing a seismic hazard area shall rneet the following requirements:
A Unless exempt. development proposals shall be subject to review standards based on two
occupcmcy types: critical facilities and other structures. The review standards for critical facilities shall be
based on larger earthquake reoccurrence intervals_ The review standards for both occupancy types shall be
set forth in administrative rules;
B. Alterations to seismic hazard areas may be allowed only as follows:
1 The evaluation of site-specific subsurface conditions shows that the proposed development site
is not located in a seismic hazard area; or
2. Mitigation based on the best available engineering and geological practices is implemented
which either eliminates or minimizes the risk of damage, death or injiiry resulting from seismically induced
settlement or soil liquefaction; and
3. Mobile homes may be placed in seismic hazard areas without performing special studies to
address the seismic hazard. Such mobile homes may be suh1ecl to special support and tie-down
requirements. These requirements shall be set forth in administrative rules.
C. Ruildings with less than 2500 square feet of fioor area or roof area (whichever is greater) that
con1r:1in no living quarters and that are not used as places of employment or public assembly exempt from the
provisions of this section. (Ord. 10870 § 47n, 1993).
21A.24.300 Volcanic hazard areas: Development standards and permitted alterations. /\
development proposal on a site containing a volcanic hazard area shall meet the following requirements:
A. Within volcanic hrvard areas located along the White River upstream from Mud Mountain Dam:
1 No critical facilities shall be constructed or located;
2_ No new apartments, ·townhouses or commercial structures shall be constructed or located;
3. /\II new lots created by subdivision, short subdivision or binding site plan shall require building
areas outside of the volcanic hazard area which shall be designated with building setback areas; and
4 New single detached residential construction on existing lots may be allowed if the applicant
records v1ith the records and elections division the following notice on all title documents:
"NOTICE"
''The structures on this property me located in an area which may be inundated by mudflows originating
on Mount R8in!er. For further information rcgardin~J this hazard, please contact King County";
i::3. Within volcanic hazard areas located c:1long the White River downstream from Mud Mountain
Dam and Green and Duwarnish Rivers: criticaf facilities shall be evaluated for risk of inundation or flooding
resulting from mudflows originating on Mount Rainier. These structures shall be designed to withstand,
without damage, the effects of mudfiows equal in magnitude to lhe prehistoric Electron Mudflow; and
C. This section shall not become effective until King County has completed the required modeling
and mapping of volcanic hazard areas. (Ord. 108/0 § 477, 1993)
21A.24_310 Steep slope hazard areas: Development standards and permitted alterations. A
development proposal on a site containing a sleep slope hazard area shall meet the following requirements:
A. A minimum buffer of fifty feet shall be established from the top, toe and along all sides of any
slope forty percent or steeper. The buffer shall be extended as required to mitigate a landslide or erosion
hazard or as otherwise necessary to protect lhe public health, safety and we~are. The buffer may be
reduced to a minim urn of ten feet if. based on a special study, King County determines that the reduction will
cJdequalely protect the proposed development and lhe sensitive area. The buffer may only be reduced to
twenty-five feet in the case of erosion hazard areas. For single family residential building permits only, King
County may waive the special study requirement and authorize butter reductions, pursuant to K.C.C.
21A.24.075 or if King County determines that the reduction will adequately protect the proposed development
and the sensitive area;
(King County 9-2004)
ENVIRONMc_N TALLY SENSITIV!= /\RE/IS 21A.24.310
B. Unless otherwise provided herein or as part of an approved alteration, remove.ii of any vegetation
from a sleep slope h,l?"rd area or buffer shall be prohibited, except for limited removal of vegetation
necessary for survcyinq purposes and for the rernov,::1! of hazard trees determined to be unsafe according to
tree selection rules promulgated pursuant to this c:hapter. Notice to King County shall be provided prior to
any vegetation removal permitted by this subsection;
C. Vegetation on steep slopes w1th'in stci?.p slope hazard areas or their buffers which has been
damaged by human activity or infested by noxious weeds may be replaced with vegetation native to King
County pursuant to a vegetation management plan approved by King County. The use of hazardous
substances, pesticides and fertilizers in steep slopP. hr.1zard arP.r.1s and their buffers may be prohibited by King
County;
D. /\Iterations to steep slope hazard areas and buffers may be allowed only as follows:
1. Approved surface water conveyances. <Js specified in the Surface Water Design Manual, may
be allowed on steep slopes if they are installed in r"1 manner to minimize disturbance to the slope and
vegetation;
2. Public and private trails may be allowed on steep slopes as approved by the county. Under no
circumstances shall trails be constructed of concrete, asphalt or other impervious surfaces which will
contribute to surface water run-off, unless such construction is necessary for soil stabilization or soil erosion
prevention or unless the trail system is specifically designed and intended to be accessible to handicapped
persons. Additional requirements for trail construction may be set forth in administrative rules;
3. Utility corridors may be allowed on steep slopes if a special study shows that such alteration will
not subject the area lo the risk of landslide or erosion;
4. Limited trimming and pruning of vegetation may be allowt~d on steep .slopes pursuant lo an
approved veget.::ition management plan for the creation and rnainteric1r1ce of views ff the soils are not
disturbed and the activity 1s subject to administrative rules;
5. Approved mining and quarrying activities may be aHowed; and
6. Stabili?ation of sites where erosion or landsliding threaten public or privc1te structures, utilities,
roads, driveways or trails, or where erosion and landsliding threatens any lake, stream, wetland or shoreline.
S\abiliLation work shall be performed in a manner which causes the least possible disturbance to the slope
and its veqetative cover; and
/. Reconstruction, remodeling or replacement of existing structures
Reconstruction, remodeling, or replacement of an existing structure upon ;:mother portion of an
existing lmpervious surface vvhich was estabflshed pursuant to King County laws ,md regulations may be
allmved provided·
a if within thP. buffer, 1he structure is located no closer to the steep slope than the existing
~>tructure,
b. the existing impervious surface within the buffer or steep slope is not expanded as a result of
the reconstruction or replacement.
E_ Point discharges from surface water facilities onto or upstream from steep slope hazard areas
that are also erosion hazard areas shall be prohibited except as follows:
1. Conveyed via continuous storm pipe downslope to a point where there are no erosion hazard
areas downstream from the discharge;
2. Discharged at flow durations matching preceveloped conditions, with adequate energy
dissipation, into existing channels that previously conveyed stormwater runoff in the predevelopment state; or
3. Dispersed discharge upslope of the steep slope onto a low-grndient undisturbed buffer
demonstrated to be adequate to infiltrate all surface and stormwater runoff.
F. The following are exempt from the provisions of this section:
1 . Slopes which are forty percent or steeper with a vertical elevation change of up to twenty feet if
no adverse Impact will result from the exemption based on King County's review of and concurrence with a
soils report prepared by a geologist or geotechnical engineer; and
2. The approved regrading of any slope which was created through previous legal grading
activities Any slope which remains forty percent or steeper following site development shall be subject to all
requirements for steep slopes. (Ord. 13190 § 21, 1998: Ord. 11621 § 77, 1994: Ord. 11273 § 5, 1994: Ord.
10870 § 478, 1993).
(King County 9-2004)
21A-201
I, I
'/1 <\ \ j/
21 A.24.320 -21 /\ 24.330 ZONING
21A.24.320 Wetlands: Development standards. A development proposal on a site containing a
wetland shall meet the following requirements:
A The following minimum buffers shall be established from the wetland edge
1. A class 1 wetland shall ha/ea 100-foot buffer,
2. A class 2 wetland shall hi've a 50-foot buffer:
3. I\ class 3 wetland shall have a 25-foot buffer;
4. /\ny wetland restored/relocated, replaced or enhanced because of a wetland alteration shall
have the minimum buffer required /Or the highest wetland class involved; and
5. Any wP.tland within 25 feet of the toe of 3 slope 30% or steeper, but less than 40%, shall have:
a. the minimum buttEl required for the wetland class involved or a 25-foot buffer beyond the top of
the slope. whichever is greater; If the l1orizontal length of the slope including small benches and terraces is
vvithin the buffer for that wctlarv:l class; or
b. 3 25-foot buffer beyond the minimum buffer required for the wetland class involved if the
horlzontal length of the slope including small benches and terraces extends beyond the buffer for that
wetland class;
El. Eluffer width ayeraging may be allowed by King County if it will provide additional protection lo
wetlands or enhance their functions, as long as the total area contained in the buffer on the development
proposal site does not decrease;
C. Increased btiffer widths shall be required by King County when necessary to protect wetlands.
Provisions for additionaLibuffer widths shall be contained in adminislm!ive rules promulgated pursuant to this
chapter including, but rlot limited to, provisions pertaining to critical drc1inage areas, location of hazardous
substances, critical fish and wildlife habitat. landslide or erosion hazard areas contfquous to wetlands,
groundwater recharge and discharge and the location of trail or utility corridors;
U. The use of hazardous substances, pesticides and fertilizers in the wetland nnd its butter may be
prohibited by King County;
E Unless otherwise provided, the following restrictions shall apply to all developrm,nt proposals
which include the introduction of livestock·
1. To prevent damage to class 1 and 2 wetlands:
a. a plan 'to protect and enhance the wetland's water quality shall be implemented pursucmt to
21A30; or
b. fencing located not closer than the buffer edge shall be required; and
2. Standard~ pertaining to access to streams for watering purposes, stream crossing requirements
and use of natural barriers and vegetative buffering in lieu of fencing shall be included in administrative rules
promulgated pursuant lo this chapter:
F. The livestock restrictions contained in subsection E. shall not apply to wetlands defined as grazed
wet meadows, regardless of their classification. (Ord 10870 § 479, 1993).
21A.24.330 Wetlands: Permitted alterations. Alterations to wetlands and buffers may be allowed
pursuant to K.C.C. 21A24.0/5 or as follows:
A Alterations rm,y be permitted if King County determines, based upon its review of special studies
completed by qualified professronals, that:
1. The wetland does not serve any of the valuable functions of wetlands identified in K.C.C.
21A06.1415 including, but not limrted to. biologic and hydrologic functions; or
2. The proposed development will;
a. protect, restore or enhance the wildlrfe habitat, natural drainage or other valuable functions of
the wetland resulting in a net improvement to the functions of the wetland system;
b. develop a plan for ils design, implementation, maintenance and monitoring prepared by a civil
engineer and a qualified biologist;
c. perform the restoration or enhancement under the direction of a qualified biologist; and
d. will otherwise be consistent with the purposes of this chapter.
(King County 9-2004)
21A-202
ENVIRONMENTALLY SENSITIVL AREAS 21A24.330
B. To establish the conditions in subsection A., detailed studies may be required as part of the
special study on h;ihitat value, hydrology, erosion and
deposition and/or water quality. Sud1 detailed studies shall include specific recommendations for mifi9ation
which may be required as a condition of any development proposal approv,.11. The rccomrnendaJions may
includ1;-;, but arc not ,
limited to, construction techniques or design. drainage or density specifications; /
C If a wclland is in a fiood hazard area, the applicant shall notify affected comp1Gnitics and native
1ribes of proposed altera1ions prior to any alteration and submit evidence or such notification to tile Federal
lns11rance Administration;
D. There shall be no introduction of any plant or wildlife which is no! indige'nous to King County into
any wetland or buffer unless authorized by a state or federal permit or approval;,, '
E. Utilities may be allowed in wetland buffers if: "
1. King County determines th;:it no practical alternative location is_,a·vailahle; and
7. The utility corridor meets any additional requirements set forih in administrative rules including,
but riot timitRd to, requirements for installation, replacement of vegetation and maintenance:
F. Sewer utility corridors may be a/lowed in wetland buffers_ only if:
1 The applicant demonstrates that sewer lines are necessary for gravity flow;
2. The corridor is not located in a wetland or buffer used by species listed as endangered or
threatened by the state or federal government or containing critical or outstanding actual h8bitat for those
species or heron rookeries or raptor nesting lrec-:s;
3. The corridor c1lignmenl including, but not li,rnlted to, any allowed maintenance roads follows a
path beyond a distance equal to seventy-five of the buff P-r width from the wetland edge;
4. Corridor construction and maintenance protects the wetland and buffer and is aligned to avoid
cutting trees greater than twelve inches in diameter at breast height, when posslble, and pesticides,
herbicides and other hazardous substcmccs are not used;
5. An additior1al, contiguous and undisturbed buffer, equal in width to the prorosed corridor
including any allowed maintenance roads, Is provided to protect the wetrand;
6. The corridor ls revegetated with appropriate vegetation native to King County at pre-construction
densities or greater immediately upon completion of construction or as soon thereaftP.r as possible, and the
sewer utf/ity ensures that such vegetation survives:
7. Any additional corridor access for maintenance is provided, to the extent possible, at specific
points rather lhan by 8 parallel road; and
8. The width of any necessary parallel road providing access for maintenance is as small as
possible, but not greater than fifteen feet, the road is maintained without the usP of herbicides, pesticides or
other hazardous substances and the location of lhe road is contiouous to the utility corridor on the side away
from the wetland;
G. Joint use of cm approved sewer utility corridor by other utilities may be allowed.
H. The following surface water management activities and facilities may be allowed in wetlands or
their buffers only EJS follows:
1. Surface water discharge to a wetland from a flow control or water quality treatment facility,
sediment pond or other surface water management activity or facility may be allowed ff the dischmge does
not increase lhe rate of flow, change the plant composition in a forested wet12md or decrease !he water
quality of lhe wetland:
2. A class 1, 2 or 3 wetland or buffer may be used for a regional retention/detention facility if:
a. a publ,c agency and utility exception is granted pursuant to KC.C 21A.24.070;
b. all refiuire~ents of the Surface Water Design Manual are met;
c. th.fuse will not alter the rating or the faclors used in raling the wetland;
d. the proposal is in compliance with the latest adopted findings of the Puget Sound Wetlands
Research Project; and
e. there are no significant adverse impacts to the wetland;
(King County 9-2004)
21A-203
21A24.330 ZONING
3. Isolated class 3 wetlands ,md buffers which arc nrazed wet meadows may be used as a flow
control facility 1f:
a. presettlement pond or water quality treatment is requirer! prior to flow irito the wetland, and
b. they are not part of, or immediately adficcnt to, an LSRI\, RSRA or a desiymited wildlife habitat
corridor and al! requirements of the Surface \/Vr1ter ncsiqn Manual are met; and
'1. Use of a \iVf)tland buffer for a surface water management activity or fc.icility, other than a flow
control or water quality treatment facility, such as an energy dissipater and associated pipes, may be allowed
only if tl1e applicant demonstrates, to the satisfaction of King County, that
a. no practicable alternative exists; and
b. the functions of the buffer or the v,1etland are not adversely affected;
I. Public and private trails may be allowed in wetland buffers only upon adoption of administrative
rules consistent with the following:
1. The trail surface shall not be made of impervious materials, except that public multi-purpose
trails such as the Burke-Gilman Trail may be made of impervious materials if they meet all other
requirements including w;iter quality; and
2. Buffers shall be expanded, where possible, equal to tt1e width of the trail corridor including
disturbed areas;
J. A dock, pier, moorage, fioat or launch facility may be allowed, subject to the provisions of K.C C
Title 25, if:
1 The existing and zoned density around the wetland is three dwelling units per acre or more;
2. At least seventy-five percent of the tots around the wetland have been built upon and no
significant buffer or wetland vegetation remains on tl1ese lots; and
3. Open water is a significant component of the wetland;
K Alterations to isolated wetlands may be allowed only as follows:
1. On sites of less than t\.venty acres in size, one isolated welland may be altered by relocating its
functions into a new wetland on the site pursuant to an approved mitigation plan;
2. On sites twenty acres or greater 1n size, up to three Isolated wetlands may be altered by
combining their functions into one or more replacement wetlands on the site pursuant to an approved
mitigation plan; and
3. VVhenever an isolated wetland is altered pursuant to this subsection, the replacement wetland
shall include enhancement for wildlife habitat;
L. One additional agricultural building or associated residence may be allowed within the wetland
buffer on a grazed wet meadow if all hydrologic storage !s replaced on the site;
M. Subject to a clearing and grading permit issued pursuant to KC.C chapter 16.82, the cutting of
up to one cord of firewood may be permitted in buffers of five acres or larger in any year if the overall function
of the buffer is not adversely affected. Removal of brush may also be permitted for the purpose of enhancing
tree growth if the area of removal is limited to the diameter of the tree canopy at the time of planting; and
N. Wetland road crossings may be allowed if:
1 King County determines that no alternative access is practical;
2. All crossings minimize impact to the wetland and provide mitigation for unavoidable impacts
through restoration, enhancement or replacement of disturbed areas;
3. Crossin~s do not change the overall wetland hydrology;
4. Crossings do not diminish the fiood storage capacity of the wetland; and
5. All crossings are constructed during summer low water periods.
0. Reconstruction, remodeling, or replacement of existing structures. Reconstruction, remodeling,
or replacement of an existing structure upon another portion of an existing impervious surface which was
established pursuant to King County laws and regulations may be allowed provided:
1. If within the buffer, the structure is located no closer to the wetrand than the existing structure,
2. The existing impervious surface within the buffer or wetland is not expanded as a result of the
reconstruction or replacement.
(King County 9-2004)
ENVIRONMENTALLY SENSITIVE AREAS 21A.24.330 -21/\.24.340
P. Wetland enl1ancemcnt or restoration not associated with any other development proposal may
be allowed if accomplished according to a plan for its design, implementation, maintenance and monituriny
prepared by a civil engineer and a qualified biologist and carried out under the direction of a qualified
blotoyist. Restoration or er1ha11cement must result in a net improvement to the functions of the wetland
system; and
0. A minor wetland restoration project for fish habitat enhancement may be aUowed if:
1. l he res1oration is sponsored by a public agency with a mandate to do such work;
2. The restoration is not associated with mitigation of a specific development proposal:
:3. The restoralion is limited to revegetatron of wetlands and their btiffers and other specific fish and
w1\Clife habitat improvemf.'nts that result in a net improvement to the functions of the wetland sys tern;
4. The restoration only involves the use of hand labor and light E-~quipment, or t11e use of helicopters
and cranes which deliver supplie~ to the project site provided that they have no r;ontact with sensitive areas
or lheir buffers: and
5. The restoration is performed under the direction of a qualified biologist. (Ord. 13190 § 22, 1998:
Ord. 11621 § 78. 1994 Ord. 11273 § 6, 1994: Ord. 10870 § 480, 1993)
21A.24.340 Wetlands: mitigation requirements.
A Restoration shall be required if a wetland or its buffer is altered in violation of law or without ;my
specific permission or approval by King County. The following minimum requirements shall be met for the
restoration of a wetland'.
1. The original wetland configuration shaH be replicated including its clerth, width, length and
gradient at the original location;
2. r tie ori~31naf soil type and configuration shall be replicated;
3. T~1c wetland edge and buffer configuration shall be restored to its originJI condition;
4. Tile wetland, edge and buffer shall be replanted with veyetstio11 native to King County that
replicates the orlg1nat vegetation 1n species, Sizes and densities; and
5. The oriqimil _wetland functions shal! be restored indudiny, but not limited to, hydrologic and
biologic fur1ctions.
8. I he rcquircrnerits in subsection A. of this section rnay be modified if the applicant demonstrates
that qreatcr wetland functions can otherwise be obtained.
C. Replacement shall be required if a buffer is altered under an approved development proposal or
a wetland is Lised for a reyiona! flow control facility or other approved use Ttie requirements for the
restoration of 1Nctlarids shall be met by replacement wetlands.
0 Er1hancement may be allowed if a wetland or buffer wi\\ be altered under to a developmP.nt
proposal, but the wetland's biologic and/or hydrologic functions will be improved. Minimum requirements for
enhancement shall be established in administrative rules.
E. All alterations of wetlands shall be replaced or enhanced on the site or within the same drainage
basin using the following formulas: class 1 and 2 wetlands on a two-to-one basis and class 3 wetlands on a
one-to-one basis with equivalent or greater biologic functions including, bul not limited to, habitat functions
and with equivalent hydrologic functions including, but not limited to, storage capacity.
F. Replacement or enhancement off the site may be allowed if the applicant demonstrates to the
satisfaction of King County that the off-site location is in the same drainage sub-bas\n as the original wetland
and that greater biologic and hydrologic functions will be achieved. The formulas in subsection E ol this
section shall apply to replacement and enhancement off the site.
G. Surface water management or flood control alterations including, but not limited to, wetponds
shall not constitute replacement or enhancement unless other functions are simultaneously Improved_
H. Mitigation sites should be located to alleviate wildlife habitat fragmentatio11 and avoid impacts to
and prevent loss of farmable land within agricultural production districts. (Ord. 14045 § 48, 2001. Ord.
13190§23.1998: Ord.11621 §79, 1994: Ord.10870§481, 1993).
; I], V .. )
(King County 9-2004)
21A--205
,r\'0
21 A 24.345 · 21 A.24.360 ZONING
21A.24.345 Wetlands: mitigation banking. King County may consir:er and approve
replacement or enhancement of unavoidable adverse impacts to wetlands caused by the development
activities through an approved wetland mitigation bank. Wetland mitigation banking ts not allowed in the
agricultural production districts if the purpose is to compensate for fiifing wetlands for development outside
of the agricultural production district;;_ Compensatory mitigation 1n advance of authorized impr.tcts must be
provided through an approved mitigation bank. Criteria governing the creation and use of a rnitrgation
bank shall be established 1n administrcJtivc rules. A pilot project or projects, complete with evaluation
should be initiated that would test the viability of 1he mitigation bank concept before to its full
1mple111entation ;Ord 14045 § 49, 2001: Ord. 11621 § 72, 1994 ).
21A.24.350 Wetlands: Limited exemption. Isolated wetlands less than 1000 square feet may be
exempted from the provisions of K.C.C. 21A24.320 · 21A24.340 cJnd may be altered by filling or dredging 1f
King County determines that the cumulative impacts do not unduly counteract the purposes of this chapter
,md are mitiyated pursuant to an approved mitigation plan. (Ord. 10870 § 482, 1993).
21A.24.360 Streams: Development standards. A development proposal on a site containing a
( .. ,stream shall m~et the followinq requirements:
A The\following minimum butters shall be established from the ordinary high wotcr mark or from the
lop of the bank if., the ordinary high water mark r:annot be identified
1. A class 1 stream shall have a 100 foot buffer;
2. A cl3r5s 2 stream used by salmonids shall have a 100-foot buffer:
3 A claSs 2 stream shall have a 50-foot buffer;
4. /\ class 3 stream shall have a 25-foot buffer,
5. ln the Bear Creek Basin, class 1 and 2 streams used by salmonids, shall have a 150-foot buffer;
6. In the 130-ar Creek Easin, a class 2 stream not used by salmonids, shall have a 100-foot buffer;
7. In the 8e,1r Creek Basin, a class 3 stream shall h,we a 50-foot buffer except in designated
regionally significant ·resource are,1s where a c!ass 3 strenm shall have a 1 OD-foot buffer;
8. Any stream restored, relocated, replaced or enhanced because of a stream alteration shall have
the minimum buffer required for the strerim class involved,
9_ Any slremn with an ordinary high water mark within 25 feet of the toe of a slope 30% or steeper,
but less than 40%, shall have·
a_ the minimum btJffcr required for the slream class involved or a 25-foot buffer beyond the top of
the slope, whichever is greater, if the horizontal length of Hie slope including small benches and terraces is
within the buffer for that s.tream class; or
b. a 25-foot buffer beyond the minimum buffer required for the stre~_nn class Involved if the
horizontal length of the slope including small benches and terraces extends beyond the buffer for that stream
class; and
10. Any stream adjoined by a riparian wetland or other contiguous sensitive area shall have the
buffer required for the stream class involved or the buffer which applies to the wetland or other sensitive area,
whichever is greater;
B. tluffer width averaging may be allowed by King County if it will provide additional natural resource
protect1on, as long as the total area contained in the buffer on the development proposal site does not
decrease;
C. Increased buffer widths shall be required by King County when necessary to protect streams.
Provisions for additional buffer widths shall be contained In administrative rules promulgated pursuant to
this chapter including, but not limited to, critical drainage areas, location of hazardous substances, critical fish
and wildlife habitat, landslide or erosion hazard areas contiguous to streams, groundwater recharge and
discharge and the location of trail or utility corridors;
D. The use of hazardous substances, pesticides and fertilizers in the stream corridor and its buffer
may be prohibited by King County; and
E:. Tlie livestock restrictions in K.C.C. 21A24.320 shall also apply to class 1 and 2 streams and their
buffers except that barrier fencing shall not be required in the floodplain of the Snoqualmie River. (Ord
12015§4, 1995: Ord 10870§483, 1993).
(King County 9-2004)
21A-206
ENVIRONMENT /\I LY SENSITIVE ARlcAS 21/\24.370
21/\.24.370 Streams: Pennitted alterations. Alterations to slreams and buffers may be allowed
pursuant to K CC. 21 A.24 075 or as follows:
A. Alterations mc1y only be permitted if based upon ;:i special study.
B. The applicant shall notify affected communities anrl native tribes of proposed alterations prior to
any a!tcratfon if a stream is in a flood ha7ard area and shr-111 submit evidence of such notification to the
Federal Insurance Administration;
C. There shall be no introduction of any plant or \1vildlifc which is nut indigenous to King County into
any stream or buffer unless authorized by a state or federal permit or approval;
0. Utilities may be allowed in stream buffers if:
1. No practical alternative location ·1s available;
2. The utility corridor meets any additional requirements set forth in administratfv.e'rules including,
hut not limited to, requirements for installation, replacement of vegetation and rnaintenanc,e;
and
3. The rec,uirements for sewer utility corridors 111 K C.C. 21/\.24.330 shall also apply to streams;
/
4. Joint use of an approved sewer utility corridor by other utilities may be allowed;
E. The following surface water management activities and facilitate~ .. rnay be allowed in stream
buffers as follows:
1. Surface waler discharge to a stream from a flow control or /ater quality treatment facility,
sediment pond or other surface water management activity or fac1l1ty may1be allowed if the discharge is in
corr,pliancc with the Surface Water Desl[Jn Manual; 1
2. A class 2 stream or buffer may be used for a regional storrm;ater managemP-n! facility if:
a. a public aqency and utility exception is granted pursuant ty'K.C.C 21/\.24.070;
b. all requirements of tt)e Surface Water Design Manual are met;
c. the use will not alter the rating or the factors used in rat)hg the strP-am;
d. there are no significant adverse impacts to the streon:i'. and
3. A class 3 strec1rn or buffer may be used as a regidn<1! stormwater man.1gement facility if the
alteration will have no lasting adverse impact on any stream .a'nct all requirements of the Surface W8tcr
Design Manual are met; ,
r. Except as provided in subsection G. public and Private trails may be allowed in stream buffers
only upon adoption of administrative rules consistent with the/allowing:
1. The trail surface shc1II not be rnade of imperyious materials, except Iha! public multi-purpose
trails such as the Burke-Gilman T mil nrny be rnacJe :bf impervious materials if they meet all other
requirements Including water quality; and
2. Buffers shall be expanded, whew possible, equal to the width of the trail corridor including
disturbed areas; /
G. Stream crossings may be allovvcd and rnaY encroach on the othervvise required stream buffer if
1. All crossings use bridges or other conslruction techniques which do not disturb the stream bed
or bank, except that bottomless culverts or other 3ppropriate methods demonstrated to provide fisheries
protection may be used for class 2 or 3 streams ,I/the applicant demonstrates that such methods and their
imµlernentation will pose no harm to the stream or./~hiblt migration of fish;
2. All crossing are constructed duri?t} the summer low flow and are Urned to avoid stream
disturbance during periods when use is critical to;salmonids;
3. Crossings do not occur over saln;:rOnid spawning areas unless King County determines that no
other possible crossing site exists; /
4. Bridge piers or abutments arc/not placed within the FEMA floodway or the ordinary high water
mark;
5. Crossings do not diminish the flood-carrying capacity of the stream;
6. Underground utility crossings are laterally drilled and located at a depth of four feet below the
maximum depth of scour for the base flood predicted by a civil engineer licensed by the state of Washington.
Temporary bore pits to perform such crossings may be permitted within the stream buffer established in
K.C.C 21/\.24.360. Crossing of Class 3 streams when dry may be made with open cuts; and
7 Crossings are minimized and serve multiple purposes and properties whenever possible;
(King County 9-2004)
21/\-207
21A24.370 70NING
H. Stream relocations may be allowed only for:
1. Class 2 streams as part of a public road proJect for which a public agency and utility exception is
granted pursuant to K.C.C. 21A24.050; and
2. Class 3 streams for the purpose of enhancing resources 1n the stream if:
a. appropriate floodplain protection mec1sures are used; and
b. the relocation occurs on the site. except that relocation off the site may be allowed if the
applicant demonstrates that any on-site relocation is Impracticable, the 3pplicant provides ;ill necessary
easements and waivers from affected property owners and the off-srte location is in the s3rne drainage sub-
basin as the original stream;
L For any relocation allowed by this sec:tion, the applicant shall demonstrate, based on information
provided by a civil engineer and a qualified biologist, that:
1.The equivalent base f!ood storage volume <1nd function will be maintained;
2. There wHI be no adverse Impact to ioca! groundwater;
3. There will be no increase in velocity;
4 There will be no interbasin transfer of waler;
5. There will be no increase in sediment load;
6 Requirements set out in the mitigation plan are met;
7 The relocation conforms to other applicable laws; and
8. J\11 work will be carried out under the direct supervision of a qualified biologist;
J. A stream channel rnay be stabilized IL
1 _ Movement of the stream channel threatens exlstlng residenti,11 or commercial structures, public
facilities or improvements, unique natuml resources or the only existing access to property; and
2. The stabilization is done in compliance with the requirements of K.C.C. 21A.24.230 through
21/124.270 ,md administrative rules promulgated pursuant to this chapter:
K. S!rearn enhancement not associated with <.my other development proposal may be allowed if
accomplished according to a p!an for its design, implementation, maintemmce and monitoring prepared by a
civil engineer and a qualified biologist and carried out under the direction of a qualified biologist;
L. A minor stream restoration project for fish habitat enhancement may be allowed If:
1. The restoration is sponsored by a public agency wiH1 a mandate to do such work;
2. The restoration is unassociated with mitigation of a specific development proposal;
3. The restoration is limited to placement of rock wiers, log controls, spawning gravel and other
specific salmonid habitat Improvements;
4. The restoration only Involves the use of hand labor and light equipment; or the use of helicopters
and cranes which deliver supplies to the project site provided that they have no contact with sensitive areas
or their buffers, and
5. The restoration is performed under the direction of a qualified biologist;
M. Roadside and agricultural drainage ditches which carry streams with salmonids may be
maintained through the use of best management practices developed in consultation with relevant county,
state and federal agencies. These practices shall be c::1dopted as admirnstrative rules;
N. Subject to a clearing and grading permit issued pursuant to K.C C. 16.82, the cutting of up to one
cord of firewood may be permitted in buffers of five acres or larger in any year if the overall function of the
buffer is not adversely affected. Removal of brush may also be permitted for the purpose of enhancing tree
growth if the area of removal is limited to the diameter of the tree canopy at the time of planting.
0. Reconstruction, remodeling, or replacement of existing structures. Reconstruction, remodeling,
or replacement of an existing structure upon another portion of an existing impervious surface which was
established pursuant to King County laws and regulations may be allowed provided;
1. If within the buffer, the structure is located no closer to the stream than the existing structure,
2. The existing impervious surface within the buffer or stream is not expanded as a result of the
reconstruction or replacement. (Ord. 13190 § 24, 1998; Ord. 11621 § 80, 1994; Ord. 11273 § 7, 1994; Ord.
10870 § 484, 1993)
(King County 9-2004)
21 A--208
ENVIRONMENTALLY SENSITIVE AREAS 21A.24.380 -21A.24420
21A.24.380 Streams: Mitigation requirements.
A Restoration shall be required when a strenm or its buffer is altered in violc:ition of !aw or without
any specific permission or approval by King County. A mitigation plan for the restoration shall demonstrate
that
1 Tr,e stream has been degraded and 1Nil\ not be further degraded by the restoration activity;
2. The restoration will reliably and demonstrably ,mprove the water quality and fish and wildlife
habitat of the stream;
3. The restoration will have no lasting significant adverse impact on any stream functions; and
4. The restoration will assist in stabilizin[J the stream channel
B. The following minimum requirements shall be met for the restoration of a stream
1. All work shall be carried out under the direct supenvision of a qualified biologist;
2. Basin analysis shall be performed to determine hydrologic conditions;
3. The natural channel dimensions shall be replicated including its depth, width, length and
gradient at the original location. and the original horizontal alignment (meander lengths) shall be replaced;
4. I he bottom shall be restored with identical or similar materials;
5. Ti1c bank and buffer configuration sh811 be restorP.d to its original conditior1;
O_ The channel, bank ond buffer areas shall be reptanted 1.vith vegetation na1ive to King County
which replicates the original veuet3tion in species, sizes and densities; and
7 _ The original biologic. functions of the stream shall be recreated.
C. The requirements in subsection B. rnay be modified if the applicant demonstrates lo the
satisfaction of King County that a greater biologic function can otherwise be obtained;
D. Replacement or enhancement shall be required when a stream or buffer is altered pursuant to an
approved development proposal. There shall be no net loss of stream functions on a development proposal
site and no im,:}act on stream functions above or below the site due to approved alterations
E. /he rf:quircrnents which apply lo the restoration of streams in subsection 8_ shall also apply to
the relocation of streams, unless the applicant demonstrates to the satisf~iction of King County that a greater
biologic function ccm be obtained by modifying these requirements.
F. Rcplacen1ent or enhancement for approved stream alterc1tions shall be accomplished in streams
and on the site unlPss the applicant demonstrates to the satisfaction of King County that:
1. Er1hanccrnent or mplacP,ment on the site i.s not possible;
2. The off-site location is in the same drainage sub-basin as the original stream; and
3. Greater biologic and hydrologic functions will be achieved
G_ Suriace water management or flood control alterations shall not be considered enhancement /.:~.1
unless other functions are simultaneously improved. (Ord. 10870 § 48!::i, 1993).
21A.24.390 Sensitive areas mitigation fee -Creation of fund. There is hereby created a
Sensitive Areas Mitigation Fund. This fund shall be administered by the King County Office of Finance.
(Ord. 10870 § 486, 1993).
21A.24.400 Sensitive areas mitigation fee -Source of funds. Al! monies received from penalties
resulting from the violation of rules and laws regulating development and activities within sensitive areas
shcill be deposited into the fund. (Ord. 10870 § 487, 1993).
21A.24.410 Sensitive areas mitigation fee -Use of funds. Monies from the fund sl1all only be
used for paying the cost of enforcing and implementing sensitive area laws and rules. (Ord. 10870 § 488,
1993).
21A.24.420 Sensitive areas mitigation fee -Investment of funds. Monies in the fund not needed
for immediate expenditure shall be deposited in a separate investment fund pursuant to RCW 36.29.020
The director shall be designated as the investment fund director. (Ord. 10870 § 489, 1993)
(Kin<:) County 9-2004)
,,
21A.24 500 70NING
21A.24.500 Sensitive area designation.
A.1. A property owner or the property owner's agent m;::iy request a sensitive area designation for
part or all of a site, without seeking a permit for a development proposal. by filinq with the departrmmt a
written application for a sensitivP-area rlesignation on a form provided by the department If the request is for
review of a portion of a site, the application shall include a map identifying the portion of the site for which the
designation is sought
2. The designation shall be limited to the following determinations:
a. The existence, location, ~md boundaries of any stream, wetland, coal mine hazard area,
landslide hazard area or steep slope on the site; and
b. The cl;issifiec1tion of r1ny stream or wetland.
3. The designation shall not include any evaluation or interpretation of the applicability of sensitive
area butters or other sensitive areu standards to a future development proposal.
B. In preparing the sensilive area designation, the department shall perform a sensitive area review
to:
1. Determine whether any sensitive area that is subject to this designation process exists on the
site and confirm its type, location, boundaries and classification;
2. Determine whether a special study is required to identify and characterize the location.
boundaries and classification of the sensitive area;
3. Evaluate the special study. if required; and
4. Document the existence, location and classification of any sensitive area that is subject to this
designation process
C. If required by the department, the applicant for a sensitive area designation shall prepare and
submit to the department the special study required by subsection B.2. of this section.
D. The department's deterniination of a sensitive area designation shall be made in writing within
one hundred N/enty days after !he application for a sensitive area designation js complete, as provided in
K.C.C. 20.20.050 The periods set forth in K.C.C. 20.20.100A.1 through A.5 shall be excluded from the one-
hundred-hventy-day period. The written determination made pursuant to this section as to the existence,
location, and classlflcation of a sensitive area shall be effectlve for hrvo years from the date the determination
is issued. The department shall rely on the determination in its review of a complete application for a permit
or approval filed within two ye8rs after the determination is issued. lf the determination applies to less than
an entire site. the determination shall clearly identify the portion of the site to which the determination applies.
E. The applicant for a sensitive area designation shall be responsible for fees as provided in K.C.C
litle27.
F. If the department designates sensitive areas on a site pursuant to this section, the applicant for a
dcvc!opmcnt proposal on that site shall submit proof that a sensitive area notice on title has been filed as
required by K.C.C. 21A.24.170.
G. The department by rule may provide for the designation of other sensitive areas identified by this
chapter as established by council ordinance in addition to those provided for in this section.
H.1. Except as provided in 2. of this subsection. the department's determination under this section is
final.
2. If the department relies on a sensitive area designation made pursuant to this section during its
review of an application for a permit or other approval of a development proposal and the permit or other
approval is subject to an administrative appeal, any appeal of the designation shall be consolidated with and
is subject to the same appeal process as the underlying development proposal. If the King County hearing
examiner makes the county's final decision with regard to the permit or other approval type for the underlying
development proposal, the hearing examiner's decision constitutes the county's final decision on the
designation. If the King County council, acting as a quasi-judicial body, makes the county's final decision with
regard to the permit or other approval type for the underlying development proposal, the King County
council's decision constitutes the county's final decision on the designation. (Ord. 14187 § 1, 7001)
(King County 9-2004)
21A-210
ENVIRONMENTALLY SENSITIVE /\REAS 21/\.24.510
21A.24.510 Effect of approval of septic system design based on sensitive area
designation. If the department of Seattle-King County public health approves a septic system design
based on a sensitive area designation made pursuant to K.C.C. 21A24.500 and the applicant submits a
complete application to the department of development and environmental services within two years after
the date the department of development and enviror11nental service issues the sensitive area designation
under K.C.C. 21A24.500, the standards of this chapter 1n effect at the time of the department of Seattle-
King County public health's approval of the septic system design shall apply to the department of
development and environmental sen;ices's dcterrn1nation of whether the septic system design complies
with the provisions of this chapter for those sensitive areas for which a sensitive area designation has
been issued. (Ord. 14187 § 2, 2001).
(King County 9-2004)
211\-211
GENERAL
Sections:
27A10005
27A10010
27A10 020
27A10030
27A10040
27A10050
Title established.
Purpose.
Provisions.
i\pplicabilily.
Rules.
Severability.
Chapter 27A.10
GENERAL
27A.10005-27A 10050
27A.10.005 Title established. Thero is hereby created a new title in the King Counly Code entitled
Financial Guarantees. (Ord. 12020 § 1, 1995 ).
27A.10.010 Purpose. The purpose of this title is to establisl1 authority and procedures for accepting
and enforcing financial guarantees. with the intent of assuring that development projects are completed and
maintained in accordance with county approval conditions. (Ord. 12020 § 2, 1995).
27 A.10.020 Provisions. This chapter sets forth provisions general to the administration of financial
guarantees and includes: applicability. default, financial guarantee conditions. financial guarantees-form and
amount, performance guarantee reductions. release of financial guarantees, scheduling of performance,
maintenance and defects inspections, financial guarantee waivers. and status of current financial
guarantees (Ord. 12020 § 9, 1995). \(C.C 2.7A8
27A.10.030 Applicability. The provisions of this title shall apply to permits and approvals granted fi...-..ClAl..
pursuant to Titles 9, 14, 16. 19. or 21A (or their successors) of the King County Code. (Ord. 12020 § 10. c..v\>·<"•,: oe5.
1995).
27A.10.040 Rules. The department is authorized to adopt, pursuant to K.C.C. 2.98, such rules as
are deemed appropriate to implement this title. The director may prepare and require the use of such forms
as are deemed appropriate for its administration. (Ord. 12020 § 31, 1995).
27 A.10.050 Severability. Should any chapter. section, subsection, paragraph, sentence, clause or ~
phrase of this title be declared unconstitutional or invalid for any reason. such decision shall not affect the
validity of the remaining portion of this title. (Ord. 12020 § 57, 1995). C!.of>J
(King County 12-95)
27A-3
27A20.010 -27A20 060
Sections:
27A 20.010
27A20.020
27A.20.030
27A20.040
27A20.050
27A20 060
Applicant.
Default.
Department
Director.
Financial guarantee.
Guarantor
Chapter 27 A.20
DEFINITIONS
FINANCIAL GUARANTEES
27A.20.010 Applicant. "Applicant" means the person or entity who is required to post the financial
guarantee. (Ord. 12020 § 3. 1995).
27 A.20.020 Default. "Default" means the failure to:
A. comply with financial guarantee conditions:
B. complete. in the specified time. the required improvements in accordance with the King County
Code and with approved pro1ect plans and cond1tior1s; or
C. maintain, for the specified period of time, the required improvements in accordance with the King
County Code and with approved project plans and conditions. (Ord 12020 § 4. 1995).
27 A.20.030 Department "Department" means the King County department of development and
environmental services or its successor organization. (Ord. 12020 § 5, 1995 ).
27A.20.040 Director. "Director" means the director of the King County department of development
and environmental services or his/her designee. (Ord. 12020 § 6, 1995).
27 A.20.050 Financial guarantee. "Financial guarantee" means a form of financial security posted
to ensure timely and proper completion of improvements, to ensure compliance with the King County Code,
and/or to warranty materials, workmanship of improvements, and design. Financial guarantees include
assignments of funds. cash deposits. surety bonds, and/or other forms of financial security acceptable to the
director. For the purposes of this title, the terms performance guarantee, maintenance guarantee and defect
guarantee are considered sub-categories of financial guarantee. (Ord. 12020 § 7, 1995).
27 A.20.060 Guarantor. "Guarantor" means a bank or other acceptable entity which issues the
financial guarantee. (Ord. 12020 § 8, 1995).
King County 12-95)
27A-4
ADMINISTRATION
Sections:
27 A.30.010
27A30.020
27A30030
27A30 040
27A30.050
27A30 060
27A.30.070
27A30.080
27A30 090
27A.30.100
Chapter 27 A.30
ADMINISTRATION
Financial guarantee conditions.
Financial guarantees-form and amount.
Performance guarantee reductions.
Release of financial guarantees.
Scheduling of final performance, maintenance, and defect
inspections.
Financial guarantee waivers.
Status of current financial guarantees
Performance guarantees authorized.
Maintenance and defect guarantees authorized
Default.
27 A30.010 -27 A30 030
27A.30.010 Financial guarantee conditions. A Every financial guarantee shall obligate the
applicant to comply with all of the provisions of the King County Code and complete all conditions required
by the permit or approval within the time limit specified.
B. The county may collect against the financial guarantee when work is not completed in a timely
manner in accordance with conditions of the permit and/or approval granted pursuant lo Titles 9. 14, 16. 19,
or 21A (or their successors). It is in the director's sole reasonable discretion to determine whether the permit
or approval conditions have been satisfied in a timely manner. and to determine whether the performance
guarantee shall be collected to remedy the violation. The director shall notify the applicant in writing of any
such determination. (Ord. 12020 § 12, 1995).
27 A.30.020 Financial guarantees-form and amount. Financial guarantees shall be in a form
approved by the director. in consultation with the department of natural resources and parks. department of
transportation, the prosecuting attorney's office. and other affected agencies. The amounts of the financial
guarantees shall be based on the schedules appropriate to the required work which are updated on a
periodic and frequent basis to ensure that the amount fully captures likely costs. Financial guarantees shall
also require a contingency in an amount to be determined by the director. (Ord. 14199 § 249, 2001: Ord.
12020 § 13, 1995)
27A.30.030 Performance guarantee reductions. The director may allow reductions in
performance guarantee amounts in accordance with the county's cost estimate of the work remaining to be
completed. No more than one reduction will be allowed except that two reductions may be allowed at the
director's discretion for phased subdivisions. The reduction shall not exceed 70% of the initial guarantee
value including contingency. The request for reduction shall be in writing, accompanied by a schedule for
completion of remaining work. (Ord. 12020 § 14. 1995)
(King County 12-2001)
27A-5
27A30 040 · 27A.30.080 FINANCIAL GUARANTEES
27 A.30.040 Release of financial guarantees. The department shall not release performance
guarantees until all permit fees have been paid to date; maintenance guarantees and defect guarantees
have been posted. if applicable: inspection of the development site has been performed; and the director
has determined :hat the conditions and requirements of the permit/approval otherwise specified in tl1e
financial guarantee have been met and granted final construction approval if applicable. (Ord. 12020 § 15,
1995)
27 A.30.050 Scheduling of final performance. maintenance, and defect inspections. The
department shall be responsible for scheduling final performance. and maintenance and defects inspections.
The department should schedule such inspections approximately forty-five days prior to expiration of the
performance or maintenance period. If necessary to determine completion of performance, additional
inspections should also be made after the expiration of the performance period. Periodic inspections may
also be made at the discretion of the director of the deparlment of development and environmental services,
the director of the department of natural resources and parks or the director of the department of
transportation (Ord. 14199 § 250, 2001 Ord. 12020 § 16, 1995).
27 A30.060 Financial guarantee waivers. Consistent with chapter 36.32 RCW, King County shall
not require any state agency, unit of local government. or gas company or electrical company (as those
terms are defined in RCW 80 04 01 O) to secure the performance of a permit requirement with a financial
guarantee as a condition of issuing a permit or approval for a building construction project. The director,
however, may require such state agency or unit of local government, gas company or electric company to
sign an agreement to complete required improvements and protect the County's rights and duty to remedy
unsatisfactory performance. (Ord. 12020 § 17, 1995).
27 A.30.070 Status of current financial guarantees. All financial guarantees required by the
department and posted by the applicant prior to the effective date of this ordinance shall continue to be in
force until released by the director following satisfactory compliance with financial guarantee conditions.
(Ord 12020 § 18. 1995).
27 A.30.080 Performance guarantees authorized, A The department is authorized to require all
applicants constructing improvements pursuant to any permits and approvals granted pursuanl to Titles 9,
14, 16. 19. or 21A (or their successors) of the King County Code to post performance guarantees with the
director to guarantee completion of required improvements and compliance with the King County Code.
B If more than one such guarantee is required, the applicant may. with the permission of the
director, and to the extent allowable by law, combine guarantees provided, that at no time shall the
guaranteed amount be less than the total amount which would have been required in the form of separate
financial guarantees; and provided further, that such guarantee shall on its face clearly delineate those
separate additional financial guarantees which it is intended in lieu of.
27A-6
ADMINISTRATION 27 A.30.080 -27 A.30.100
C Unless otherwise specifically indicated in the King County Code. performance guarantees shall
require actual construction and installation of required improvements within two years after recording for final
subdivision. tvvo years after recording for short subdivision. one year after right-of-way permit issuance or six
months after temporary building occupancy issued for a building permit The time limit for performance
guarantee compliance may be extended by six rnonths at the director's discretion, if circumstances beyond
the control of the applicant warrant an extension. The request for an extension shall be in writing.
accompanied by a schedule for completion of remaining work. (Ord 12020 § 19, 1995).
27A.30.090 Maintenance and defect guarantees authorized. A The department is authorized to
require all applicants to post a maintenance guarantee and/or defect guarantee warranting the successful
operation and maintenance of improvements. and guaranteeing the workmanship, materials. and design
used in construction of improvements required by the conditions of any permits or approvals issued pursuant
to titles 9, 14, 16. 19. or 21A; (or their successors) and assuring compliance with the King County Code.
B. Unless otherwise specifically indicated in the King County Code, all maintenance guarantees
and defect guarantees shall guarantee successful operation, workmanship, materials, and design of
required facilities for a period or two years following final inspection and approval of improvements.
C Inspections of facilities required pursuant to Titles 9, 14. 16. 19, or 21A (or their successors)
should be scheduled by the appropriate department approximately forty-five days prior to the end of the two
year maintenance and/or defect period. (Ord. 12020 § 20, 1995)
27 A.30.100 Default. A Determination of default shall be made by the department after an
inspection has indicated that improvements need to be corrected or completed. In the event of failure to
comply with any of the conditions and terms of the permits and/or approvals covered by this title, the director
shall notify the applicant and guarantor in writing of the default. If satisfactory assurance is not received by
the department within a time period determined by the director, that conditions will be appropriately
corrected, the department may:
1. order the applicant to perform all necessary corrective work. and/or
2. demand payment on the financial guarantee(sj. Nothing in this title shall limit the ability of
King County to enforce or otherwise compel compliance with conditions of any county permit or approval in
accordance with any enforcement provision set forth in Title 23 of the King County Code.
B. The guarantor shall be responsible. up to the limits of the financial guarantee. for the payment of
any and all necessary costs and expenses that have been or will be incurred or expended by King Counly in
causing any and all such required work to be done. In the event that total costs associated with the required
work exceed the guarantee amount the applicant shall remain responsible to King County for the payment
of any remaining amount
C In the event of default, King County may contract with a third party to complete work required
pursuant to this title. (Ord. 12020 § 11. 1995i.
(King County 6-98)
27A-8
27A.40.010 -27A40 030
Sections:
27A40.010
27A.40.020
27A40.030
27A40.040
27A40 050
27A40.060
27A40.070
27A.40.080
27A.40.090
27 A.40.100
General.
Drainage improvements.
Chapter 27 A.40
REQUIREMENTS
Restoration and reclamation activities.
Rights-of-way.
Site development and restoration.
Subdivisions.
Landscaping
Sensitive areas.
Section 309 financial guarantees.
Moved and temporary buildings.
FINANCIAL GUARANTEES
27A.40.010 General. The following provisions set forth special financial guarantee requirements for
certain improvements required pursuant to Titles 9, 14, 16, 19 or 21A (or their successors) of the King
County Code. (Ord. 12020 § 21, 1995).
27A.40.020 Drainage improvements. Financial guarantees for drainage improvements pursuant to
K.C.C. Title 9 shall be sufficient to cover the time and cost of any:
A. Monitoring required by approved plans and conditions;
B. Department review of monitoring results and reports: and
C. Corrective work on or off the project site which is necessary to provide drainage control
consistent with approved plans and conditions, stabilize and restore disturbed areas and remove sources of
any hazard associated with work which is in progress but is not completed. (Ord. 13189 § 8, 1998: Ord.
12020 § 22, 1995)
27 A.40.030 Restoration and reclamation activities. A. Financial guarantees for restoration and
reclamation activities required pursuant to Title 16 and Title 21 A shall be sufficient to cover the cost of
conformance with conditions of the permit, including corrective work necessary to provide drainage
consistent with approved plans and conditions, to remove geologic hazards, and to protect water quality and
the public health, safety, and welfare. The financial guarantee may be reduced proportionately for phased
projects as work is complete and subsequent reclamation and/or restoration on each phase is completed.
The request for reduction shall be in writing.
B. Financial guarantees may be waived on:
1. ProJects of less than one thousand cubic yards,
2. King County department projects, and
3. Reclamation projects with financial guarantees posted with the state of Washington
Department of Natural Resources or with the federal office of surface mining.
C A cash guarantee shall accompany the operating permit and may be used after proper notice at
the discretion of the director to correct deficiencies affecting public health, safety and welfare. including
effects on water quality. The amount of the cash guarantee shall be determined by the director, and shall be
maintained at the full value established by the director at all times during the life of the permit (Ord. 12020 §
23, 1995)
(King County 6-98)
27A-9
REQUIREMENTS 27A40 040 -27A.40.060
27A.40.040 Rights-of-way. Financial guarantees for any right-of way improvement required
pursuant to Title 14 shall be sufficient to cover the cost of restoring the right-of-way to original condition or
complying with conditions of any permit or approval, including corrective work necessary to provide drainage
consistent with approved plans and conditions. and to protect the public health. safety and welfare. (Ord.
12020 § 24, 1995).
27 A.40.050 Site development and restoration. A. Financial guarantees for any improvement
required pursuant to Titles 16, 19, or 21A (or their successors) shall be sufficient to cover the cost of
complying with conditions of the permit or approval. including corrective work necessary to provide drainage
consistent with approved plans and conditions, to remove geologic hazards. and to protect water quality and
the public health, safety, and welfare. Such financial guarantees shall include site restoration and
stabilization requirements.
B. No temporary certificate of occupancy shall be issued until:
1 Drainage facility improvements are functional:
2. Required parking is provided: and
3 Safe access is provided.
C. The director rnay allow a performance guarantee to be posted for some or all of the
improvements required by subsection B of this section 1f no life safety hazard exists. The request shall be
rnade in writing, accompanied by a schedule for completion of required improvements. (Ord. 12020 § 25.
1995).
27A.40.060 Subdivisions. A. Pursuant to RCW 58.17. 130. an applicant rnay request recording of a
subdivision prior to the completion of the construction of required improvements subject to the posting of a
performance financial guarantee. Performance guarantees for subdivisions which record prior to completing
all improvements shall be subject to the following requirements:
1. A performance guarantee shall be posted with the department in an amount equal lo the
director's estimate for such improvements as assurance that the applicant will, within two years from the
date of recording of the final subdivision, complete the improvements in accordance with the requirements
and to the satisfaction of the development engineer (as defined in Title 19 or its successor):
2. Requests for performance guarantees shall be in writing. shall be correlated with the original
terms and conditions of preliminary approval, and shall be accompanied by a detailed schedule for
completion of the improvements and conditions,
3. Performance guarantees for improvements required pursuant to Title 19 ( or its successor)
shall be sufficient to cover the cost of conformance with conditions of the preliminary approval and approved
construction plans, including corrective work necessary to protect the public health, safety, and welfare.
4. Maintenance guarantees and defect guarantee shall be posted with the director:
a. prior to final construction approval and recording of the final plat when the applicant has
constructed improvements in accordance with the approval of the director and the development engineer. or
b. prior to final construction approval and the release of performance guarantees vvhen lhe
applicant has previously recorded the plat.
5. Maintenance guarantees and defect guarantees shall be released following a final
maintenance and defect inspection and, if applicable, acceptance of the facilities for county maintenance.
(Ord 12020 § 26. 1995)
(King County 6-98)
27A-10
27 A.40 070 -27 A40.100 FINANCIAL GUARANTEES
27 A.40.070 Landscaping. A. Prior to receiving a temporary or permanent occupancy certificate for
any building or structure for which Title 21 A requires landscaping. an applicant shall provide the required
performance guarantee to secure the completion and improvement of required landscaping, in accordance
with approved site plan, within three months following issuance of the building or buildings temporary or
permanent occupancy certificate. whichever comes first.
B Performance guarantees for landscaping required pursuant to K.C.C. 21A.16 shall be sufficient
to cover the cost of conformance with conditions of the permit, and shall be required for a period of two
years after the planting or transplanting of vegetation to insure proper installation. establishment and
maintenance. This time period may be extended by one year by the director, if necessary to cover a
planting and growing season
C. The director rnay extend the time limit for compliance with the above landscaping requirement up
to one year after issuance of the occupancy certificate if circumstances beyond the control of the applicant
warrant an extension. The request for an extension shall be in writing, accompanied by a schedule for
completion of remaining work. (Ord. 12020 § 27, 1995).
27A.40.080 Sensitive areas. A. Financial guarantees for mitigation required pursuant to K.C.C.
chapter 21A.24 shall be sufficient to guarantee that all required mitigation measures will be completed no
later than tl1e time established by King County in accordance with K.C.C. chapter 21A.24.
B. Performance and maintenance guarantees shall also be required for restoration of a sensitive
area or buffer not performed as part of a mitigation or maintenance plan except that no financial guarantee
shall be required for minor stream restoration carried out pursuant to K.C.C. chapter 21A.24.
C. For maintenance guarantees associated with mitigation, corrective work, restoration or
enhancement, the financial guarantee shall be sufficient to cover the time and cost to guarantee satisfactory
workmanship, materials and performance of structures and improvements required by K.C.C. chapter
21A.24 and any n10nitoring of lhose structures and improvements required by approved plans and
conditions.
D. Public development proposals shall be relieved from having to comply with the provisions of this
section if public funds have previously been committed for mitigation, maintenance. monitoring or
restoration. (Ord. 13189 § 9, 1998: Ord. 12020 § 28. 1995).
27A.40.090 Section 309 financial guarantees. Financial guarantees required pursuant to Section
309 of the King County modifications to the current Uniform Building Code shall be in the form of cash
deposited with the director. assignment of funds approved by the director, or in an irrevocable escrow in an
amount sufficient to restore the building and site. and to perform corrective work required by Title 16 of the
King County Code. (Ord. 12020 § 29. 1995).
27A.40.100 Moved and temporary buildings. Financial guarantees required wi\11 respect to moved
or temporary buildings pursuant to Section 104 (e) of the King County modifications to the current Uniform
Building Code shall be in the form of cash deposited with the director. assignment of funds approved by the
director, or in an approved irrevocable escrow in a sufficient amount to be determined by the director. (Ord.
12020 § 30, 1995)
(King County 6-98)
27A-11
IYl'' ~~~~~i if
K~w~G cour~irv
r~{ ro 0o\ [)\\ 011"' ~\\ ff\\, n ~I ® ra D ccs:i U\\\VIJ=\\ JJ ~ u ~u~lYnuDI~/~~
1~9)8
LOUIS J. HAFF, P.E.
County Road Engineer
King County
Department of Public Works
1. OJ
1. 02
1. 03
1.04
1.05
1.06
1.07
1.08
1.09
1.10
1 . 11
2.01
2.02
2.03
2.04
2.05
2.06
2.07
2.08
2.09
2.10
2 .11
2 .12
2.13
2.14
2.15
2.16
2.17
2.18
2.19
KING COUNTY ROAD STANDARDS 1993
TABLE OF CONTENTS
PURPOSE
CHAPTER 1. GENERAL CONSIDERATIONS
Shortened Designation
Applicability
Responsibility to Provide Roadway Improvements
General References
WSDOT/APWA Documents as Primary Design and Construction References
Other Specifications
Road Plans
Variances
Penalties and Financial Guarantees
Meaning of Terms
Severa bi Ii ty
Road Classifications
Arterial Roads
Residential Access Streets
Commercial Access Streets
CHAPTER 2. ROAD TYPES & GEOMETRICS
Horizontal Curvature and Sight Distance Design Values
Private Streets
Half Streets
Cul-de-sacs and Eyebrows
Alleys and Private Access Tracts
Intersections and Low Speed Curves
Maximum Grade and Grade Transitions
Stopping Sight Distance
Entering Sight Distance
Medi ans
One-Way Streets
Bus Zones and Turn-Outs
Exception to Paving on Rural Minor Access Streets (Residential)
Intersections with State or Federal Highways
Slope, Wall, & Drainage Easements and Right-of-way Reduction
2
2
2
3
4
4
4
5
6
6
B
9
10
11
12
13
14
15
16
17
18
19
19
20
20
21
21
21
21
22
TABLE CF CQ\rTENTS (Continued)
2.20 Access and Circulation Requirements
2.21 Exception for Maximum Dwelling Units on Urban Subcol lectors
3.01
3.02
3.03
3.04
3.05
3.06
3.07
3.08
3.09
3.10
3 .11
4 01
4 02
4.03
4 04
4.05
5.01
5.02
5.03
5.04
5.05
5.06
5.07
5.08
5.09
5. JO
5. 11
CHAPTER 3. DRI\/E\11/AYS W/11..KS, & TRAILS
Driveways
Concrete Sidewalks
Curbs. Gutters and Sidewalks
Expansion and Durnnf Joints
Curb Ramps
Concrete Steps, Metal Handrail and Handicapped Access Ramps
Asphalt Shoulders
Separated Walkways, Bikeways and Trails
School Access
Bikeways
Equestrian Facilities
CHAPTER 4. SURFACING
Residential Streets, Pedestrian and Bike
Requirements for Residential Streets on Poor Subgrade
Arterials and Commercial Access Streets
Materials&. Lay-Down Procedures
Pavement Markings, Markers, and Pavement Tapers
Rock Facings
Side Slopes
Street Trees & Landscaping
Mail Boxes
Street Illumination
Survey Monuments
Roadway Barricades
Bollards
Guardrai 1/Embankment Heights
Off-Street Parking Spaces
Roadside Obstacles
CHAPTER 5. ROADSIDE FEATURES
22
23
24
26
27
27
28
28
28
29
29
29
30
32
34
34
34
35
37
39
39
39
41
41
41
42
42
42
42
TABLE CF CONTENTS (Continued)
CHAPTER 6. BRIDGES
6 01 Principal References
6 02 Bridge Geometrics
6.03 Bridge Design Criteria
6.04 Special Permits
CHAPTER 7. DRAINAGE
7.01 General
7 02 Road Ditches
7.03 Storm Sewers and Culverts
7 04 Catch Basins and Junctions
7.05 Frames, Grates, and Covers
7.06 Erosion Control
7.07 Trenches
CHAPTER 8. UTILITIES
8.01 Franchising Policy and Permit Procedure
8.02 Standard Utility Locations Within the Right-of-way
8.03 Underground Utility Installation
8.04 Final U ti Ii ty Adjustment (To Finish Grade)
8.05 Final Cleanup, Restoration of Surface Drainage and Erosion Control
CHAPTER 9. CONSTRUCTION CONTROL AND INSPECTION
9.01 Basis for Control of the Work
9.02 Subdivision, Commercial and Right-Of-Way Land Use Inspection
9.03 Penalties for Failure to Notify for Land Use Inspection
9.04 Embankment Construction Control in Developments
9.05 Traffic Control in Development Construction
906 County Forces and County Contract Road Inspection
9.07 Call Before You Dig
i i i
44
44
44
45
46
46
47
48
49
50
50
51
51
54
57
58
59
59
60
61
61
62
62
TABLE CF ruJTENTS (Continued)
SECTION 1-0 0 0 fU\[)/\1\y
D rawi nq Number
1-001
1-002
1-003
1-004
1-005
1-006
1-007
1-008
1-009
1-010
1-011
SECTION 2-000 DRAINAGE
Drawing Number
2-001
2-002
2-003
2-004
2-005
2-006
2-007
2-008
2-009
2-010
2-011
2-012
2-013
2-014
2-015
2-016
2-017
2-018
DRAWINGS
Drawing Title
Shoulder Type Roadway
Vertical Curb Type Roadway
Rolled Curb Type Roadway
Gravel Surface Roadway
Thickened Edge Roadway
Extruded Curb Roadway
Cul -de-Sacs
Temporary Cul-de-Sac
Eyebrow
Half Street
Alley Pavement Detai 1
Drawing Title
Beveled End Pipe Section
Field Tapping of Concrete Pipe
Catch Basin Type 1
Catch Basin Type 1-L
Catch Basin Type 2 -48", 52", 60", 72" & 96"
Catch Basin Details
Manhole Type 1 -48", 52" & 60"
Manhole Type 2 -72" & 96"
Manhole Type 3 -48", 52", 60", 72" & 96"
Manhole Type 4
Manhole Dela i 1 s
Curb Inlet
Standard Grate
Standard Frame with Vertical Curb Installation
Solid Cover
Through-curb Inlet Frame
Through-curb Inlet Frame and Grate with Vertical Curb Installation
Vaned Grate
iv
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
TABLE OF CONTENTS (Continued)
Drawing Number
2-019
2-020
2-021
2-022
2-023
2-024
2-025
2-026
2-027
2-028
Drawing Title
Rolled Curb Frame and Grate
Rolled Curb Frame and Grate Installation
Rolled Curb Vaned Grate
Locking Manhole Cover
Locking M3nhole Frame
Rock-line~ Shoulder Ditches & Curbed or Turnpike Shou 1ders
Flo~ Restrictor/Oil Pollution Control Device, Tee T~p, (FROP T)
FROP-T Shear Gate Detail
Flow Restrictor/Oil Pollution Control Device, 33Tfle Type (FROP-B)
Debris Cage
SECTION 3-000 CURB & DRIVEWAY
Drawing Number
3-001
3-002
3-003
3-004
3-005
3-006
3-007
Drawing Title
Curb and Sidewalk Joints
Curb Details
Shoulder and Ditch Section Driveway
Curb and Gutter Section Driveway
Reverse Slope Driveway
Location and Width of New Driveways
Joint Use Driveway Tract
SECTION 4~000 SIDEWALKS & CURB RAMPS
Drawing Number
4-001
4-002
4-003
4-004
Drawing Title
Curb Ram~ Locations
Curb Ram~s in Vertical Curb
Curb Ram~s in Rolled Curb
Cement Concrete Sidewalk Transition to Asphalt Shoulder
SECTION 5-000 ROADSIDE APPURTENANCES
Drawing Number
5-001
5-002
5-003
5-004
Drawing Title
Clearance of Roadside Obstacles on Shoulder Type Road
Intersectlom Landing
Barricades
Rock Facing, Cut Section
94
95
96
97
98
99
100
!OJ
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
TABLE CF CO\fTENTS (Continued)
Drawi nq Number
5-005
5-006
5-007
5-008
5-009
5-010
5-011
5-012
5-013
5-014
5-015
Drawing Title
Rock Facing, Fi 11 Section
Rock Facing Under Sidewalk
Rock Facing, Fi 11 Section Reinforcement
Concrete Steps and Metal Handrail
Street Tree Standards
Mailbox Mounting, Curb Type Location
Mailbox Mounting, Shoulder Type Location
Neighborhood Delivery & Collection Box Unit (N.D.C.B.U.) Mailbox Installation
Bollards
Roadway Survey Monument with Case and Cover
Off-Roadway Survey Monument
vi
119
120
121
122
123
124
125
126
127
128
129
INTRODUCED av: onuc£ LAING
PROPOS[O NO: ~931..c·.!'.6a,l8L_ __
ORD IffANC( HO. 11187
AN OROIIIANC[ approving ar.d adopting the 'Kir.g
County Road Standards', :993 update, as the
s~andards for road design b King County, aoer.c.lng
Ordi:iance No. 8041, Sections 4 and 6, a:id K.C.C.
:4.42.C30 anci. 14.42.C50, and repeali:ig and
replacing Ord::.=iance No. 8041, Sec:'..ons 2 ar.d IC and
K.C.C. :!.4 42.ClC and :4.42.090.
PREAHBLE; The King County Road Standards were last adc·pted ir. thetr
entirety :Oy King Co1.:nty Ord::.nance 8C41 dated April 27, 1987. The
proposed new publicatior. "King Co1.:nty Road Standards" updates t:1e :937
docume:it. These s:andards update, clarify and correct portior.s ~f t:1e
previous road standards. T:Jese changes are In:en:ied to support and be
part of tl'.e cour.ty's goals regarding growt:l rr.anagernent, housing and
sensitive areas.
BE :T ORDAINED BY TH( COUNCIL OF KlNG COLlHY:
SECTION 1, Ordir.ance Ko. 8G-41, Sectior. 2, as arr.e:ided and K.C.C.
:~.42.010 are.hereby repealed and be followir.g is s·Jbst1:1.::eci..
Adoption. ;,. .. 'King county Read S:a.1dEds 1 1993 ·Jp,fate, as amended
by the c:iuncil decet1ber 20, 19?3, ir.corporated herein as Attach:r,er.: A -~·i:l'.
ame:ided Sect:ons 2.03, 2.20, 21, 3.C-2, 5.C3 and 5.10 a~ Attacl'.nent Sare
hereby approved and adopted as the Ktng Co'Jnty s:ar.dards for read d.esig:i
anci co:istr,Jction.
8. Cor.s:.stent with co·JncL's direction and intent :.r. adoptir.g these
standards ::1e depa::oent of public works is hereby authorized to develop
public rules and make ~ir.or c~anges to tie d:::aw:ngs in orde: to bette:
implement the standards and as r.eeded to stay c1.:rrent wit:J changing design
ar,C. c:instructior. technology ar:d c.ethods.
c, Consistent wiL1 council's direction a::id inte::it tn adopting :l'.ese
standards the department of publlc works will estab:~sh a corrmlttee
consisting of county staff and representatives of be fire and emer·,Jency
medical S:(!rvlce and developne:it cornmuniltes. The c:iJL'llittee will
i:ivestigate alternative roadway widbs and othe: roo.d sta::idard rela:ed
issues that i~pact the ability to prc,vide emergency fire and :r.edfcc.l
service to the p1.:blic ar.d report fir.C.ir,gs back to cot:.r.cil Cy Septeiaber
1994.
SECTIO:!'l' 2. Ordinance Ko. 8Ml, sec:ior. 4 a:id K.::.c. H 42.0JC a:e
he::-by amer.ded :o read as fol:ows:
11187
Appl tub11 il.Y. A. The sta:idads rnay apply :o all newlv cons::ruc+.:ed
modification$ of roadway feat·Jres CY existi::ig facilltles whid. are within
:he scope o:: reconstnctions or ca::iital improvener.t projec'.:s w'.1en so
required. by King County or t~ the extent they are expressly referred to I!']
projec: p:a::is and specifica:icns. These s:ando.rds are :wt i:itended L
app:y to 'resurfaci:ig, restoratio:i and rehabiEtation" projects as those
:enns are de'.:ineci. in tl'.e :,ocal Agency Gu1del Ines, \./ash!ngton State
Depart:rien:: of TYansp::irtatior., as a!l'.e:lded; however, the eng1:1eer r:,ay :n hls
discretion ccnsider :he star.dards as ::iptiona~ g::ia~s.
B. ":'he s:andards sha:l applj-' to every r.ew placerr.ent and e-1ery
planned, no:i-err.erger,cy rep:o.cement of t:til :ty pdes and otl'.er 'J:il l:y
strnc:ures wltl'.in !:.ng Cc'Jnty rigf.:-of-way.
SECT:ON 3. G·:dir.o.:ice No. 8C41, Sectic:n 6 a::id K ::.c. :~ 42.0SC a:e
hereby amer,ded as follows:
References. ":'he standards irnp:ement and are intended :o Ce
consisten: with the references :isted i:1 Section 04 ~: A:tactur.ent A,
'King County Road Standard£, ((HS&)) lliJ.".
SECTION 4. Ordinance :-l'o. 8C41, Sec:ion 10 and 3:.C.C. 14.~Z.090 are
hereby repealed and the folbwing is s·Jbst:r1.::ed:
11187
Effective Date This ordinance shall take effect (30) days from its
eriactment.
-;, __r{_
INTRODUCED AUD READ tor the first Ume this __............L __ _ day of
~d ~ PASSFO this _c2..!!____ __ d;iy of T).
ATTEST
J~(/f,h<;?:d:=-
K lllG COUNTY COUNCIL
Km:; COUNTY, W/\St!a!GTOtl
(Jl~Q,<,_ J:J}-5:J
,Y
1993.
APPROVED thls _Jp ft day oi f>£,C./YLlw!.. I 19__f.z._,
\Qc_,.~M.Q __ _
........ , .. 1.o,....1 .. d.o;d
Attachment: A. Klng County Road Standards, 1993
8. Attachment B
-J-
KING CXlNTY FU'D STl'NDl'RDS 1993
RJRFC6E
King County has adopted these road design criteria primarily for a two-fold purpose:
( 1 )
(2)
To set forth specific, consistent road design elements for developers and other private parties
constructing or modifying road or right-of-way facilities which require County licenses or permits:
To establish uniform criteria to guide the County's own construction of new County roads or reconstruction
of existing roads.
In addition, these Standards are intended to support King County's goals for achieving affordable housing,
providing adequate facilities for development in an efficient manner, complying with storm water management and
sensitive area policies and to balance these goals with the general safety and mobility needs of the traveling
publ i C.
In adopting these Road Standards. the County has sought to encourage standardization of road design elements
where necessary for consistency and to assure so far as practical that motoring. bicycling. equestrian, and
pedestrian public safety needs are met. Considerations include safety. convenience, pleasant appearance, proper
drainage, and economical maintenance. The Standards also provide requirements for the location and installation
of utilities within the right-of-way. The County's permitting and licensing activities require the adoption of
specific, identifiable standards to guide private individuals and entities in the administrative process of
procuring the necessary County approval. Yet, the County must have needed flexibility to carry out its general
duty to provide streets, roads, and highways for the diverse and changing needs of the traveling public.
Accordingly, these Standards are not intended to represent the legal standard by which the County's duty to the
tr ave Ii n g pub Ii c i s t o be measured
These Standards cannot provide for a 11 situations They are intended to assist but not to substitute for
competent work by design professionals. It is expected that land surveyors, engineers, and architects will
bring to each project the best of skills from their respective disciplines. These Standards are also not
intended to limit unreasonably any innovative or creative effort which could result in better quality, .better
cost savings, or both. Any proposed departure from the Standards w i 11 be judged, however, on the likelihood that
such variance w i 11 produce a compensating or comparable result, in every way adequate for the road user and
county resident.
CHAPTER I. GENERAL CONSIDERATIONS
1.01 Shortened Desisnation: These King County Road Standards w 11 be cited routinely in the text as the
"Standards."
1.02 Applicabilitv: These standards shall apply prospectively to all newly constructed road and right-of-way
facilities, both public and private. within King County. In the event of conflict with the current short
subdivision code. K.C.C. Chapter 19.26. these Standards shall control.
The Standards apply to modifications of roadway features of existing facilities which are within the scope
of reconstructions. required off-site road improvements for land developments, or capital improvement
projects when so required by King' County or to the extent they are expressly referred to in project plans
and specifications. These Standards are not intended to apply to "resurfacing, restoration, and
rehabilitation" proJects as those terms are defined in the Local Agency Guidelines, V\EIXlT, as amended;
however, the Engineer may at his discretion consider the Standards as optional goals.
The Standards shall apply to every new placement and every planned. non-emergency replacement of existing
utility poles and other utility structures within the King County right-of-way.
1.03 Responsibility to Provide Roadwav Improvements
A. Any land development which w i 11 impact the service level. safety, or operational efficiency of
serving roads or is required by other County code or ordinance to improve such roads shall improve
those roads in accordance with these Standards. The extent of off-site improvements to serving
roads shall be based on an assessment of the impacts of the proposed land development by the
Reviewing Agency.
B. Any land development abutting and impacting existing roads shall improve the frontage of those roads
in accordance with these Standards. The extent of improvements shall be based on an assessment of
the impacts of the proposed land development by the Reviewing Agency Urban residential short plats
creating only one additional lot to a tax lot with an existing dwelling unit are exempt from
providing urban type street improvements but are subject to shoulder improvements as specified In
Section 3.07 provided these improvements are consistent with the surrounding roads.
C. Any land development that contains internal.roads shall construct or improve those roadways to these
Standards.
D. It is the County's practice that it w i I I not allow subdivisions to be recorded unless there exists a
recorded continuous public access to the subdivision except as provided for in Section 2.06. Nor
will the County accept a road for maintenance until the road is directly connected to a County or
other public I y maintained road.
2
E. A I I road
design.
Sections
improvement and development
Where existing roadways are
3.02, 3.07, 3.08 or 3.09.
pro1ects shall include pedestrian access as a part of the
to be modified. pedestrian facilities shall be as described 1n
1.04 General References: The Standards implement and are intended to be consistent with:
A 1-bne Rule Charter for King County, approved by the electorate on November 5. 1968; specifically
subsection 920.20.10.
B. King County Code, as amended, including:
Title 9,
Title 14,
Title 16,
Title 17,
Title 19.
Title 20,
Title 21,
Titles 46
Surface Water Management
Roads and Bridges
Building and Construction
Fire Code
Standards
Subdivisions
Planning
Zoning
and 47, Traffic
C. Implementing guidelines on drainage prepared by Surface Water Management Division. King County
Department of Public Works, and hereafter referred to as the "Surface Water Design Manual"
D. King County Comprehensive PI an 1985, as updated.
E. King County Transportation Plan. current edition.
F. Affordable Housing Policy Plan.
G. Adopted Community Plans.
H. King County Regional Trails Plan,
I. King County Non-Motorized Transportation Plan.
J. King County Capital Improvement Program, as amended.
K. King County Parks and Open Space Plan 1986.
L. King County Specifications for Off-Street Parking.
M King County adopted Basin Control Plans.
N. King County Flood Hazard Plan, when adopted.
3
1.05 WSOOT/APWA Documents as Primary Design and Construction References: Except where these Standards provide
otherwise, design detail, construction workmanship, and materials shall be in accordance with the
following publications produced separately by Washington State Department of Transportation (WSOOT), or
jointly by WSOOT and Washington State Chapter of American Public Works Association (APWA).
A. WSDOT/APWA Standard Specifications for Road, Bridge, and Municipal Construction, as adopted by King
County, current edition as amended. These will be referred to as the "WSOOT/APWA Standard
Specifications.•
B. The WSDOT/APWA Standard Plans for Road and Bridge Construction, to be referred to as the "WSDOT/APWA
Standard Plans," current edition as amended.
C. WSDOT Design Manual, current edition as amended.
D. City and County Design Standards for the Construction of Urban and Rural Arterial and Collector
Roads, adopted per RCW 35.78.039 and RCW 43.32.020, May 24, 1989, current edition as amended.
1.06 Other Specifications: The following shall be applicable when pertinent, when specifically cited in the
Standards or when required by state or federal funding authority.
A. Local Agency Guidelines, WSDOT, as amended.
B. Guidelines for Urban Arterial Program, WSDOT, as amended.
C. Design criteria of federal agencies including the Federal Housing Administration, Department of
Housing and Urban Development; and the Federal Highway Administration, Department of Transportation.
D. A Policy on Geometric Design of Highways and Streets, American Association of State Highway and
Transportation Officials (AASHTO), 1984, or current edition when adopted by WSDOT.
E. Standard Specifications for Highway Bridges, adopted by AASHTO, current edition.
F. U.S. Department of Transportation Manual on Uniform Traffic Control Devices, ''MUTCD'', as amended
and approved by Washington State Department of Transportation, current edition.
G. Guide for the Development of Bicycle Facilities, adopted by AASHTO, current edition.
H. Associated Rockery Contractors, Standard Rock Wall Construction Guidelines.
I. American Society for Testing and Materials (ASTM).
1.07 Road Plans: Plans for roads and road drainage shall be prepared and submitted consistent with these
Standards and in accordance with administrative rule published by the Director, Department of Public
Works. These requirements shall apply to public or private roads whether constructed by private party or
4
public agency. Subject to review, the Reviewing Agency may waive plan requirements, wholly or in part,
based on the following criteria:
A. For improvements to existing roads if:
1. No more than 5,000 square feet will be cleared and graded within the right-of-way or easement;
and
2. The existing grade or slope in the road right-of-way or easement does not exceed 12 percent;
and
3 ~h~ work will net inte~cept a st~eam er w~tland or otherwise impact natural surface drainage
as set forth in Cc"nty Cod~ ~~g3~ding s~nsitive Areas and the Surface Water Design Manual; and
4. Plans do not include a retention/detention facility within the right-of-way; and
5. The work is required of a short plat development, or a right-of-way use permit and involves
less than 100 lineal f~~t of existing public road improvement; and
6. King County standard drawings, submitted with required permits, are sufficient to describe the
improvement to be constructed.
1.08 Variances
A. Variances from these Standards may be granted by the Engineer upon evidence that such variances are
in the public interest and that requirements for safety, function, fire protection, appearance and
maintainability based upon sound engineering judgement are fully met. Detailed procedures for
requesting variances and appealing variance decisions are contained in an administrative rule
available from the County Road Engineer. Variance requests for subdivisions should be proposed at
preliminary plat stage and prior to any public hearing. Variances must be approved prior to
approval of the engineering plans for construction. Any anticipated variances from these Standards
which do not meet the Uniform Fire Code shall also require concurrence by the King County Fire
Marshal.
B. Questions regarding interpretation of thes~ Standards may be directed to the Reviewing Agency, Site
Development Coordinator, at 296 :;;640 er th~ Roads and Engineering Services Variance Engineer at 296-
3783. .
5
1.09 Penalties and Financial Guarantees: Failure to comply with these Standards may result in denial of plan
or development permit approval, revocation of prior approvals, legal action for forfeiture of financial
guarantee, code enforcement. and/or other penalties as provided by law
A. CO\IS1RLJCTIC)\J ~ GUARANTEES: Any construction work on King County right-of-way (both
maintained and unmaintained) other than Capital Improvement Projects or County maintenance work
shall be guaranteed by a financial guarantee. All work on private road and drainage facilities
required as a condition of a County approval process shall be guaranteed by a financial guarantee at
the time of plat recording. The amount and form of the financial guarantee shall be determined by
the Reviewing Agency. The minimum performance guarantee shall be $1,000.00
The amount of the financial guarantee rrny be reduced during construction, as determined by the
Reviewing Agency. At no time w i 11 the financial guarantee amount be reduced to less than 30 percent
of the original amount or $1,000.00, whichever is greater
B. M/\INTENANCE ~ GUARANTEES: The successful performance of the right-of-way improvements
shall be guaranteed for a period of at least one year (or other period if updated by King County
Code) from the latest date of either the acceptance or Final Construction Approval. The amount and
form ofthe maintenance financial guarantee shall be determined by the Reviewing Agency The
minimum maintenance guarantee shall be $1,000.00. Maintenance guarantees will not be required when
the required performance guarantee is $1,000.00.
1.10 Meaning of Terms
"Alley": A thoroughfare or right-of-way, usually narrower than a street, which provides access to the
rear boundary of two or more residential properties and is not intended for general traffic circulation:
privately maintained.
"Auxilary Lane": The portion of the roadway adjoining the traveled way for parking, turning or other
purposes supplementary to through-traffic movement.
"Bulb": Round area for vehicle turnaround typically located at the end of a cul-de-sac street.
"Cul-de-sac": Short street having one end open lo traffic and the other temporarily or permanently
terminated by a vehicle turnaround.
"Design Speed": The speed approved by the Reviewing Agency or the Engineer for the design of the physical
features of a road as established by Sections 2.03 and 2.04 for residential and commercial access streets
or equal to 10 miles per hour above the current or expected posted speed limit for arterials.
"Developer": Any person, firm. partnership, association, joint venture or corporation or any other entity
who undertakes to improve residential, commercial, or industrial property or to subdivide for the purpose
o f res a I e and p r o f i t.
6
"Driveway": A privately maintained access to residential, commercial or industrial properties.
"Engineer": King County Road Engineer, having authorities specified in RCW 36.75.050 and 36.80, or
his/her authorized representative.
"Eyebrow": A partial bulb located adjacent to the serving road that provides access to lots and serves as
a vehicle turnaround.
"Half-Street": Street constructed along edge of development, utilizing a portion of thm t<mgula~ width of
right-of-way and permitted as an interim facility pending construction of the othmt< h3ln on the stt<met by
the adjacent owner.
"Joint-Use Driveway Tract": A jointly owned and maintained tract or easement serving two properties.
"Landing': A road or driveway approach area to any public or private road.
"Loop': Road of limited length forming a loo1J, having no othmt< intet<sructing read, and functioni11g mainly
as direct access to abutting properties. A loop m31J be drusignated fot< onm-way or t1-1J-way tt<affic.
"Off-Street Parking Space": An area accessible to vehicles, exclusive of roadways, sidewalks, and other
pedestrian facilities, that is improved, maintained and used for the purpose of parking a motor vehicle.
"Pavement Width": Paved area on shoulder-type roads or paved surfacm bmtHemn cmt<b, thickened edge or
gutter flow line on all other roads as depicted on Drawings 1-001 tht<o~gh 1-003, 1-005 and 1-006.
"Pipe Stem": A strip of land having a width narrower than that of the lot or parcel to be served and is
designed for providing access to that lot or parcel.
"Private Access Tract": A privately owned and maintained tract providing vehicular access to six or fewer
residential properties.
"Private Street": A privately owned and maintained access provided for by a tract, easement or other
legal means, typically serving three or more potential dwelling units.
"Professional Engineer": A professional civil engineer licensed to practice in the State of Washington.
"Public Street": Publicly owned facility providing access, including the roadway and all other
improvements, inside the right-of-way.
"Reviewing Agency": King County Department of Development and Environmental Services or its successor
agency for plats and proposed developments.
"Right-of-Way": Land, property, or property interest (e.g., an easement), usually in a strip, acquired
for or devoted to transportation purposes.
7
"Road": A facility providing public or private access including the roadway and all other improvements
inside the right-of-way.
"Road" and ''Street" will be considered interchangeable terms for the purpose of these Standards
''Roadway'': Pavement width plus any non-paved shoulders.
"Resource Lands': r,as so designated in King Coanty Co~p~ch•nsive Plan and as implemented through
community plans and s~•3 zoning; characterized by long-ter~ sgriculture, forestry, and mining.
"Rural Areas'': Areas so designated in King County Comprehensive Plan, and as implemented through
community plans and area zoning; characterized by long-term low density of development.
"Shoulder': The paved or unpaved portion of the roadway outside the traveled way that is available for
emergency parking or non-motorized use.
"Traffic Engineer'': King County Traffic Engineer responsible for design, operation and maintenance of
traffic control devices.
"Transitional Areas": Areas so designated in the King County Comprehensive Plan; characterized by low
density but earmarked for redesignation through a community plan as either a rural or an urban area.
"Traveled Way":
"Urban Areas":
community pl ans
development.
The part of the road made for vehicle travel excluding shoulders and auxiliary lanes.
Areas so designated in King County Comprehensive Plan, and as implemented through
and area zoning; characterized by denser commercial/industrial and residential
"Utility": A company providing pHblic service such as gas, electric power, telephone, telegraph, water,
sewer, or c3ble television, wheth•~ or not such company is privately owned or owned by a governmental
entity.
I.II Severability: If any part of th•s• King County Road Standards as established by ordinance shall be found
invalid, all othe~ pa~ts sh~ll ~main in •ff~~t.
8
CHAPTER 2. ROAD TYPES &. GEOMETRICS
2.01 Road Classifications
A County roads are classified functionally as indicated in Sections 2.02. 2.03. and 2.04. Function is
the controlling element for classification and shall govern right-of-way. road width and road
geometrics. Other given elements such as access. arterial spacing and average daily traffic count
(ADT) are typical.
B. Within each functional classification. roads are further characterized as "curb" or "shoulder'' type.
A "curb" type road typically requires curb and gutter with inlets and underground pipe drainage. A
"shoulder" type road typically requires a shoulder and open ditch drainage.
1. Land developments in urban areas, as defined by the current King County Comprehensive Plan
Map. shall provide "curb" type road improvements. Exceptions to this may be approved by the
Reviewing Agency on residential access streets which are located in long-term, low density
neighborhoods as designated by adopted community plans and where a pattern of "shoulder" type
roads is firmly established. Exceptions for two-lot urban short plats are as allowed in
Section 1.03.
2. Land developments in rural areas as defined by the current King County Comprehensive Plan Map
shall provide "shoulder" type. road improvements unless otherwise approved by the Reviewing
Agency. Certain exceptions to the "shoulder" type standard may apply within clustered housing
developments and rural activity centers (unincorporated rural towns such as Vashon or Fall
City) where urban densities and uses may make a "curb" type road appropriate. Within these
developments, the specifically authorized land uses, adopted community plans or business
district design guidelines may provide for either a "curb" or "shoulder" type road section.
3. Land developments in transitional areas as defined by the current King County Comprehensive
Plan .Map shall provide "curb" or "shoulder" type road improvements as specified by the
Reviewing Agency
4. Guidelines applicable to Rural Areas shall apply also to Resource Lands.
2.02 Arterial Roads' Comprising the County primary road system, see Drawings No. 1-001 and 1-002.
CLASSJFICATION PRINCIPAL ARTERIALS MINOR ARTERIALS COLLECTOR ARTERIALS OR "COLLECTORS"
FlJNCTION Inter-community highways connecting Intra-community highways connecting Intra-community highways connecting
largest community centers & facilities community centers and facilities. residential neighborhoods with community
centers & facilities.
Access Controlled with very restricted Partially controlled with infrequent Partia1\y controlled with infrequent
access to abutting properties. access to abutting properties. access to abut1ing properties.
Land Use Area Rura\ Urban Rural Urban ------------------Rural --------------Urban
Arterial Spacing 2 to 5 Miks 2 to 5 Miles Under 2 Miles Under 2 Miles Under 2 Miles I Under2 Miles
AD·r
CRITEIUA
A T\p1c:d Rrmd T~'pc Shuldder Curb Sli,itdd::r Cu1h Sb,,.:]dcr[S) Sh,)uldei-(8] Slioukkr[SJ Cmb [9)
ll
C
D.
E.
F
(j
II.
I
J
K
L.
'
D-:~ig11 Spc::d [2] Vc1~1c~ \'cTie~ \';uK~ V<lr'.L'~ VariC'., \':me~
(MPH) 40, W -l-1) • 611 :;5 • 55 :: .;; -.;; -; ..J-(l._5() l_"'i -50
St:indard S·. rwn'kvata,111 Ft./ Ft.)[9] 0.()6 l)_(I(, (_1/)(l () 116 f) ()(, 11_()(1
Hurvontal CrnYalwc SCL' l':ibic :i I SeL· T,1Hc 2. I Sc..: l:thk l_. I St·e L1bk 2. l S,:l'T:ibk.2.1 Sec Lcbk2.l
1\-Jaximum (iradc(%,) [lj ') ') l(J 10 Ill 10
S:anJ.c1J
Stoppmg Srghl Sc:: T:ibk'"' I \cc· LLhk 2 I Sec T;ibk 2. I Sec: T:1blc 2. l \ice l :1hlc :::. I SLT L1blc 2.1
D1sla11,·c(Ft.) l4J
Stand:1,J
Entering Sight Sec T:cblc 2. I 'ice I :1bk .~ I '-iL·cL:hlc2.I Sl'l' T:ibk 2. l SccTahk2.l <..;c·c·L1hk2.l
Dist,mcc(rt.J (5]
\fo:imrnn Passing
Sight Oisl,mce Sec 1·:1bk 2.1 Sc'L' bbl( 2.1 '.'K~' Tahk:'. l c.;l'l' l;ibk ~.I Sec T,1b:L, 2.: ~,x·L1·:1k2.l
()11 '-Lane Road (Ft I
\·1immurn 2/3-Lane 2'iJ..J-44 = ') 3--l-44 2:.:' ,-\ n
Tra,·cki.'. Way 4-1.anc 44 44 44 44 44
(Fl.) [6] 5-LE1e 56 _-=-,(, )6 5(,
i1:ti11imum Rm:dway 20-Lanc 38 _5{) 44 ;.s; -;u 44 <s [8]/50 (&] 34 [8]
\Vidth ( Ft.) r<,] 4-Lane (,I) 54 17] (10 54 171 6018]
5-Lane T:. 66171 ., ". 6617]
l\'1111 R1ght-ol~ 2/3-Lane JOO 100 X4 !-1--1-(l(J (i(_i
\\\1y \Vidth {Ft) 4-Lmc ;()() l( I() \-t S--1-
5 Lm:c l()(J \(l() 1{11) \--1-
Type titTurb L'r Shuuldci :S:' Shuuk'.c1 Vcrt1c1l ( ·1.ll'b & X' Slw:ildo Vcrtic:il l 'tl:'!1 & \' Sh"ulJL"1 (i' Slmukk1
& Ditch [6] S:: 01k:1 liuttc1 &: D1tc'h (iulk'T .i: Oneil [8) & Unch [81
'" . '.
-\\' it.!1 in the aho\·c par;irnctcr-;, i;comdric dcsig11 1 eq uin:mcn is~h:i 11 be dc1erm1:1cd 1"1 lr ~rl:l'1 f1 L' arterial ni:1d~ c,i11.~i~knl \\'ilh lhc \\'SDO I I k~1 ~n \ Lm ua I
. Design spe<:J 1~ a basis r,_,r dct.:cn!ninggclltllctric ..:krnc1ch ;md d,xs lltll imply po.~tcd m kfcalh· rwrnm~1blc ~peed Cun e's ,;Id] k Jc~11,!nc·J \\'itl1in ;xu·anwtcr'i(lf B.
c·. ,mJ D <1bo\e. I See Sect1@ 2.05 1
> • l\1axi1m;in,:1r<1J1: may be exceeded l(1r'ihortdist;mcc". (SccScct1un2.11.)
-+ • S:andarJ Stoppmg Sigh1 I )i~tmic,:/SSDJ ,,h:111 appl;-u11k.~sotherwise ;i;,pnl\'.:d hy the 1-n~'.ll\Cc'I (Sec S,·c'lit'll 2.12.)
· Standard Lntcring Sight Di.,tancc ( f·Sl)J sh:ill apply at intcr~tcti,Jns wid dri\ L'W<'Y~ unb~ lllhc1wi.,c .1ppnn ,'ci by t ~c Eng1:1cc1 \ S<:L· Section 2 : .l J
h • Criteria !'or sl:i.lc and frd<:ral funding n;ay rcqu11c greatL'l \\'idt'.i. r:,1r guardr:11l 111'itall:i111l11'., \h,1ukk1> ~hall he ':\HI :'cL'l \\'1Jcr.
· Pa\ e111C11l width :r1ay he reduced tl11 Lrb,:.n ,\nn1als where bike\\'.:.ty-: ;ire :--.,it required hy 1hc N,_\11-J\fo1urucd 1'1,m.
k • Rurcd L·ulkclors may. a-; altcrnatiVL'. h:iv:,; n:i11c,d ,·urb :md gutkr ~it 111ii:i1mn:: \\·idlh or 311 i'L'cl n1r[1 10 curb
9 -Sec \cc lion 2.(15 for all(m ,·d u,,cs t>f\upnck\ "111011~ grL'<tlL'r !:'.;an (i pc:·ccnt
10
\ .C!I IL'~ Vanes
_)) -50 _"\~ • 5(1
(Ul6 (]_{)(J
Sec ·1 abk -~ 1 Sec T:ibic 2 I
10 12
Sec Tdik 2.1 Scl' T:1hlc :.:' I
Sc..: L1hlc::: I SL'C "L1hlc 2 .
Sl'L' L1hic 2.1 '-ic~-TJl,J.· 2. J
n ~(,
.j4
30 [8] 44 (7] .. 54 171
(10 (,()
s.:i
. .j' Shnuldn \'crtical Cuth
t. Dllcli (8J & G.inc1
·i
2.03 Residenti_al AcQess streets' Serving single-family development,
For multiple-dwelling development,
see Drawings No. 1-001 through 1-006.
see Section 2.04.
CLASSIFfCA T(QN
Fl"M'TIO'.\
Publicur Pri\·,1te
.\cress
Land lre Area
NEIGHBORHOOD
COLLECTORS
StrcelS l·,innc'c(1ng twr, ('T
ln(lt·c, nc1ghbPrhu,,,b ,md
I) jlKiilh Cl•lllh.:<'lmglo ::11,TI d,ur
,Jth..::1 nc1gl:borhol>Llcolkuor~.
Pub] iL SIi LC:h
Restnc'.ed. l.l>ls li-u11tu11 ;.1,cal
An·c~~ ~lr~·et \\ here kasihk.
Rural Urban
lsUBCOLLECTORS
Streets ::1111 1cl1111 c::11 c1il:11 iun
,;,i;h1:1 nc:1ghhrn·hr,nd,
1yp1Ci1lly c\1rnc·,·1ing
\cl ri<.::1{1h,,1fo,,,1dcoll· ct,111
Pubh<.:~tr..:d,
·\s llCCckd \\"ith ,('lllC
1"C'i11K!ltlllS
Rural Urban
! <JC.,\L 6CC'FSS "TIHTJ''-
SUBACCESS
STREETS
Pe1ma111:nt rnl~d1.:-~ac~. ,,r ~h,>n
1(1Cp~ (2]. cc1nn,·ct 1ng ·,, ~uhc1,l l,:,·1m~
:md nut ,1.11p1111i1c()I
thrnugh 1:-Jf'.lc
Typically pl:bhc slrcc'h
Fc11 pri\a'.c ~tr ccb \ Sc:c Sec. 2.0().)
-\~ n<.:cckd \'."Jtl1 oul:· mirnm,d
rc,tncl1<111,
Rural Crban
;\UNOR ACCTS:-i
STREETS (RESIDENTIAL i
'Permanent ,·l,1-,k-,,\,·o 01
Ju,,p,(2J. 111th 11>-.1 11.illH· pr, -.1d1:1r
,·ircubtwn,md ,1s·cc-~~ t,l ofT-
,11·..::ct p111 !;:;n_~ 111111111 1 c~idcn;i,il
development !iuun,:an,..-~
l'ub!1c ur pri\·;1:,, \lrc:~h
I.Sc:..: Sec. 2 0(1. !
:\, nceJc:d with ,m::. m1111mal
1·..:,t1ic·tit11h
Rural Urb,m
Sc.:r\·mg P,1ll:nti:.d ~mnlx:r nf
Single.family Dwelling Units
CR!Th!UA
Over 100 31 IOO Max. JOO Max. 4 50 Max. :50 Max. l6 Max. 16 Max.
-~-· ;.:. · ,i: ·). ·· .~ x=::-::::, ::::N:,h::f::MhiW%i
A T1r1cal Rwd T\ p,· Curb Sh,iulde1 Curb Slll''.tkk1 Curb Shoukkr Curb
R. Dc~itt:n Speed !SJ
,~.,,m 11 ,~ ~~ ){)
C Ma\ Supcrclc\at1on(Ft./Ft.) 0.0(, Sec Sec. 2.058 (1_(1(,
.>(1
·"-'C Sec. 2.058
l_m1 :-ip~·cd ( ·urw
Scc'Sti::. 2.10
S<'c Ste. 2.05B
l.ln1· Sr,·cd Cur-,'e
Sc:c: Sec. 2.: tl
Sec S~c;,)_,_-Om_
l u11 Spcc·d ( ·:1ne
S..:c Sec. 2 Ill
:--,·e Sec. 2.0SB
I m1 Spc:l'd('1.11c
Sc:.: Sec. :'. :o
\ec' Sec. 2.0.'lB
D. Honz(mtal('urvat11rc:
\1in. K;1dm, {Fl.\
l .11\\" Spc:·:d ( ·:1n c Low Spec'd r·urn· L,,\1 Spc:,·d C11nc l.l>1,· Spc<.:d ( 'urh:
Sc('T.ihk.2.1 5e<"·]jbJ~::' Sc,,,·1:1t-ik: I S,·,· 'I :1hlt· :' ,; S,·c Sec . .2 lil SccSec . .21() SecSec.210 Sc;;Sec.210
E \fa.\.. Grade (61
Standard S1,,pp11ig: .Si.l,':ht
D1~ta:1ec (Ft.) {71
C. Swndard Enk1mg Sight
D1sta11..:c (Ft.) f81
H Min l'avcmci_l! \Vilit_h_(_f_t_l
!\·fin Rt>ad\\'.1\' Width (Fl.) [I LI
J. J\.fr1 Ri_c'11H,f-way Width (.Ft_,l
K. fypc,,fCLuhmShuukkr
and D:tch {111
L Mm lfall"St f'a\rd \\"1d1h(f::!_J_
\1 Min. Onc-wJy Paved \\'idihUJJ
"\' NOTJ·.S
II
Sc:c:T:ihk2.I
Sc..: T:ibk 2 I
22
_lS
(,O
8' Sh(1uldc:1
&D1t.:h F131
:::o
'()
1,
Sc,: l.ihk 2.2
s~·--I ;ihk'
"·~·
32r91
~il
V~rnol
('urh&..(iutkr
20
21)
I' li I'
Sc:c: T.ibk::'. I Se<' 1·:1hk22 I ~o \ 1 ~() ft
:• 2~ :::o 2-1
1:,. 'S .'X ,,
(,(I 4sr121 4~[121 4Df!il
8' Shuuk~'r \',;rncai or R,1llcd 4' ShoulJc: \'<:n1c,il 0r ?..oik<l
S.Dttch fl31 Curb & (ju\kr &.l)1tch f131 Curb& Gutter
''1 20 20 21)
2ll 21) :'.(I :o
\'1."ithin rhc 1b1,.,.c: paramc:lc:rs. gcomc:u·ic d~s1gn for spccfLc ~ucc1, ,hall be Ull:-;1,;:cn:with AASI-ITO I', 1;1(:, nn ( rr,1E1,·t1 i,· Lk,1g:r, 01· 111.l.''.m aJ ~ :,n,l Str..:c:r,;
2 • Sc:e S,:c:tiun 2.15 fo1 unc-\\JY lmip,;.
3 -Sec Scction 2.20 l\lr r~~i<l~·rn1Jl access e<:l:mc:ct.on requ1Mne1't~
4 -Sc:c: s~·ct1011:.2 1 fo:· urb,m cxcept1un..:nte:·1.:
" i '.',{) .\
20f\Ol
'~ f\0\
-1.~ fl21
-I' ShuulJ<:1
& l),ich rl)I
:'.I)
;,Q
'.' • De,;1g:n srcc:d 1s a b:i,i, fr1rdek·rn1mi:i)c'grurndT1cdements awl due:~ nut :mph pu,tcd 111 .q:a:I;, 1'cnrns.,1bk ,;,..:<:,'.. Cun csslull h,, cks1gnc·d \\'lthm p<irJmcters rifH. C ,md ll ,1li,1w
(SceSec110n2.0'.')
(1, l\foxnrnun grad1; may bc('XCCc'<l,·d forshond1~t.1ncc's IS..:..: .-,cl'li,,:1,: I)
7 , S:an<lard Swppmg Sight l)j,;unc~ (SSL) I ,;h:tll ,ippl y unk,s \1lhc:111 i:;,· appn1wd h1 1hc :'.11rci11cc1 I See Scdiun 2 12 i
S • S:andar<l EntcringSight Distance (ESD) ~hall .ipp:y ,11 in:cr,~(11\ilh<md dm c11·:ivson n..:1,;hh\1rhood ,:ol kl·tor~ unit,,_,; otheTWisi;: app1111·cd by tile Fn.c:incc1 I Sc:c: Scdiu:1 2.13)
9 • ?•frighborhoodrnllccwrs mkr~<:ctmg 111th arteri,ils sha'.I be ]6 fc:d ,11Jc for the first I ~O kcl Sec Sect1011 'l.(I~ r111 u1,c:1,
IO , Exception to p,Mng requ1ren:ent 011 mmt1r :iccc% ~lwu:d,T 11 pc' ~\reel,: (Sec Se,·111>11 ~-I 7 J
11 • For guardrail ms1:tll.1tw:t, ,h,n1kkrs ~hall be tm, -led \1·idc1
12. R1gh:-ol~wziy(or c:ascmcn1)may be: rcdwnl ll• minurnum ro,1d11i!y wid1h pli1~ ,idc11 alk~.pw1·1,!cd'.ha1 all potential s..:n rng u11:111c::;a11d nc:cc:-8<\l'}' dr,tinagc:uc
othen\·ise JC<:ommodakd ,in permanent ..:,1~cn1e111, within the· dc:v,·l,1pn:c11t ( Sc:c: Sc:t:11(111::: 19 J
13 • A, allc:r:.Mtivcw shoulder and J!lch. underground p1pcdram:1gc' w11h c:11:1,'r 1 hwll'11cd bl!:'''-lh1·!:' 1-01).'i ut !'xtnukdCi1rh, D\I':'· 1-00(• 1,.; acccp(;thlc
11
[,
150 \
4orm
\'cn1c,il ut R,,llcl.!
Ct11':; & (iun..:1
;:'(I
___ :'.I)
2.04 Commercial Access streets' (See Drawings No. 1-001 and 1-002 .)
CL\sSIFIC\TlON MliLTJPLE D\\TLUKi BUSINESS INDUSTRJAL ~J\10R .\CCJ::5S
ACCESS STREETS :\lX'l:SS 'lT!ffF IS ACCESS S rnrr1 S STRFFTS f( '()1\-1\iFRC'I .\ L 1
FU\CTTON Loci! st1·ccb <1lrnttmg two-I clC:ll ;;trc'l'.ts abuaing Local ~tr.',·L ahun1ng L.1c.li ~ll'C:c'b prn1·iding
Lurnly anJ 11ailliplc-dm:lli1'g J,·n ,..: m1. I ( 1 p I,· -J,,, ~ 11 i r.~ ·,111J 11n:rn1··.1cturi11g. pw,:(~\ltlg. (' 1rnil;(.1011 .111J <1cc·~~s '.o
do :.:l\)!'ll1Cll'. \,·1·\ 1~-c>. office, ;irofc~,i,lJl:d ~1m111:2 & ku1Jlin,! :1c:1'.·111.-~ p,1rkin~' rnH'. ln;1d111g sill'~
:1Cll\'ltl,'~ ,,it'·1i:1 l11L:lt1-J\\'C.:111~:.
'..'·L.~:1ll:.,~ .• md ir,d::~mal
dc1 ..:l,nmcll\ h(1t:11...iaric·~
Public m Pri1·atc Strech Typically p·.1bl1c si.rc-..:t:.: T: pi,:cil I~ :-iubk ~tTL',-h l Yrll':111;-;1t1lil1~ ~tn:(ts Pu\1[1( ur prl\ ".11( ~tl'C','1,
s.:rvi11:; ;.ill RJ) ,:nd R\l zrnws ~l'l"\Tl~ R\[ ')1)11 ,11:d ,:II Jl scn·mg C(i :m~I ,di \1 Zm1c·~ ( '.-ic'L '.-,.;,·ti(,]I 2.()(, I
l'\<::Cnt RM qllU I busi11..:~~ 1 !Olk'>
:\CC<.:~> A~ needed. \\'1lh S(lllll.' A, IK((.kJ. \\ ilh ~()]'.'.~ :'\s 11ec.:dnl. '.':ith \nine \, nc,,,L,cJ '.\ ith \lll h mint::1:11
rei:1u\ation. rel!.u!ation. lre1>ulation. rcslrictiom.
Land Use Area -·1t ~ CRlTERlA ., .. ,-, '" ,. ;:
A. T"nical Road T"ne Shoulder Curb Shoulder Curb Shoulder Curb Shoulder Curb
B. Design Speed [2] Low Speed Low Speed
(MPH) 35 35 35 35 35 35 See Sec. See Sec.
2.IO 2.10
C Max.Sunerelevation fft//Ft.l 006 0.06 0.06 0.06 0.06 0.06
D. Horizontal Luw Speed Curve Low Speed Curve
Curvature See Table 2.1 See Table 2. ! See Table 2.1 Sec Table 2.1 See Table 2.1 See Table 2.1 See Sec See Sec.
Min. Radius CFt.) r2l 2.10 2.10
E. Maximum Grade
(%)13] 12 12 12 12 II 11 12 12
F. Standard
Stopping Sight See Table 2.1 See Table 2.1 See Table 2. l Sec Table 2.1 .See Table 2.1 See Table 2.1 150 150
Distance (Ft.) f41
G. Standard
Entering Sight See Table 2.1 See Table 2.1 See Table 2.1 See Table 2. I See Table 2. l See Table 2.1 NIA NIA
Distance (Ft.) rs1
H. Min. Pavement Width (FU 22 36 24 36 24 40 20 24
L Min. Roadway Width (Ft.) r61 38 36 40 36 40 40 28171 24 171
J. Min. Rie.ht-ofWav Width fft.) 60 56 60 56 60 60 48171 40 [71
K. Type of Curb or Shoulder 3' Shoulder VenicaJ 8' Shoulder Ver1icat 8' Shoulder Venical 4' Shouldu Vertical
& Ditch 161 & Ditch Curb & Gutter & Ditch Curb & Gutter & Ditch Curb & Gutter &Ditch Curb & Gutter
L. Min. Half Street Paved Width {Ft.) 20 20 20 20 20 20 20 20
M. Min. One-Wav Paved Width fftl 20 20 22 22 24 24 20 20
N. NOTES:
\\"1::1111 thl' :1\H\\<.: para111clc1·,.; :ccorncrri,-J,,>i:_c!t1 rccuircmcnt, -"C,,rn:nc1·~·:;il A.c..:c~~ Strc:b" ~enc :nultipk-J\1-el i111g. hu,1nc,~. ilriJ i11J1.qnal ck1 ~'i(lpmc:1h
sbll he tkkrmincd flJr s;,ccir[(: ~lrC<:t.s LW1~:~tc:1t \\'111'. The' WSDOT fksi.~n :Vfam:,il
. l)c~il_'.:ll .~p,'cd 1~ ,\ bt\b fur Jctcrn1inmg !_'.COilh''.r.c ckllll'llb :m<l doc~ nul imp I:. :,osll'd (JI k.~,dl:, pcr1111ss1··,lnpc'c'c! Cui°' ca >h:.i!l be dc~1g1wd \\ 11lrnc p:11 ,1m.:tc1·ani'B,
(·. and l)Jbm,· ('.-IC~ :K"Cti,1:11.U~ 1
. \f;:ix1tff.l!TI ~radc r1ay he excec(kd !er ~hort d1.\tancc.:,,. (Scee Sl'cti,.m :' 11.)
4 • Slc\11C,'.rd Steopp:n~ '-;ighl [):stcrncc (SSD) ~h:dl c1ppl)' unless: ,.,1hcH\ 1.,,· <tp)'rn1,cd b; the l-n~·inccr 1 '-;,y \c:.11:,n 2. 12. !
.:'i -Standard Fntcr111g Sight D:~t:rncc ,:fSD) ~ha:: apply :11 intcr~c<:thltl~ :md dn1.·/\\Jy, :xl·~pt 1111 Jl'illN :1ccc,, ,11cL'h u11k" w. 1cr-,1·:~c :iprrn'-··:d hy the' Fnµ,11.:c1
(S(L' SL·,·110111.L~.'1
(l • Fu:· ~uiirJrail :11~1alla11mh.shmild,·1,.,h:.ill b,· 11\1, JL'el -.,1dc·
7 • R1gi;l-(>f-w;1:' I c)I L'<lSellKlll I may Ix: 1educcd tu milllllllllll J"()c\lh;:c1\ \\'ldlil. pith ,1dC\\ ,1ik pn:\"lded 1h;\t )'(lktll1:il .,C\I 111µ i:ti::1:l'~ J: d llc'l'l'~'idl"\ tl1 ~I.ILi.,!~ : IC ulhen1 i.,c.:
acconwd:.itcrl 11·1thm pcrnnn:cnt,:,1scn1<:nh th:-1lE;Jr". rh,-d,-,. clopn1c.:111. I Sec Scct111:1 :' J l.l 1 ·
12
2.05 Horizontal Curvature and Sight Distance Design Values
A. The do,sign values sho~ in Ta~lms 2.1 and 2.2 are minimum values ~eco,ssary to merul tWro requirmmronts
of Sections 2.02, 2.03 and 2.04 for a selected design speed and read classificat on. A rnaxirn(,lfj of 8
percent superelevation may be used, upon approval of the Engineer, for design of improvernron1.s to
existing arterials, as necrossary, to meet terrain and right-of-way conditions. Supermlevation -wn-
off leng+_hs on arterials, rural residential and commercial accruss st-eets shall be ca-:'culated h
accordancru with the WSDOT Drusi gn Manual.
B Superelevation is not requirrud in thru d sign of horizontal wrvros on urban rrosidential access
streets; hoo:ever, horizontal curvrus mus be designed based on design sprorod and selructed cross
sroction as indicated in Tabh 2.2. Tab m 2.2 is based en AASHTO "Low Sprurod Urban 'treets" design
mruthodology. Supero,Jevation may bm usm on Jrban ro,sidrunt il stremts as nmcmssary tc merut terrain
aod right-of-way conditions.
Table 2.1
Arterial Roads, Rural Residential And Co11111ercial Access Streets
Design Values
Design Speed (mph) 30 35 40 45 50
Horizon~al Curvaruure for 6 percrunt 273 3m0 509 656 849
Superelruvation, adius I Ft )
Horizontal Curvature for 8 prurco,nt (maximum 250 350 465 600 760
allowable on arterials) superele•ation,
Radius (Ft.) (requires approval Of me
Enginerur)
Stopping Sight Cistamce (Ft.) 200 250 325 400 475
~ntering Sight Oistamco, (Ft.: 430 490 555 620 685
Passing Sight Distance (Ft.) for a 1,100 1,300
2-Lane Road
I, 500 1,650 1,800
13
55 60
1,061 1,348
960 1,200
550 650
750 810
1,950 2,100
Table 2.2
Urban Residential Access Streets Design Values
Design Speed (mph) I 25 30 35
1 ~ -, -I
Horizontal Curvature, fer 6 Percmnt Suemrmlmvaticn, Radiws (Ft.) ~ -135 215 320, __ __,,
Horizontal Curvature, fer 4 Percent Sup(l)relmvaticn, RadL,s (Ft.) ~ ---· -145 230 345:----<I
Horizontal Curvature, fer 2 Percent Supmrmlmvation, Radi,s (ft.) I--155 250 .::::37c.::5:---11
Horizontal Curvature, Ncrma· Crown Section, Radiws (Ft.}
1---.---=-===---------.-180 300 460:----11
I-Stopping Sigh!__2!stan..s;._i£.! } 150 200 250
1
1-En!e.!:ing Sigh!..E_!~tan~(Ft.} 365 4~0 490
1
Minimum Run-Off Length (Ft.) 80 90 100
2.06 Private Streets
A. While corrrnunity street requirements are usually bmst served by public streets, owned and maintained
by thm County, privatm streets may be appropriatm for some local access streets. Usually these are
minor access stremts, mither residmntial or commmrcial.
B. Private streets may be approved only when they are:
1. Permanently established by right-of-Woy, tract er masement providing legal access to each
affected lot, dwelling unit, or businillss and su~ficien-to accommodate required improvements,
to include provision for future use b11adjacent prcper-y owners when applicable; and
2. Built to King County Road Standards, as set forth herein, or secured under the provisions of
K.C.C. 19.24.040; and
3. Accessible at all times for emergency and public service vehicle use; and
4. Not obstructing, or part cf, the present or future public neighborhood circulation plan
developed in processes su~r, as the King County Comprehensive Plan, applicable community plan,
or Capital Improvement Prcgram; and
5. Not going to result in land locking of present or future parcels; and
6. Not needed as public roads to meet the minimum road spacing requirements of these Standards;
and
14
Designed to serve a maximum potential of I~ single-family dwelling units when the entire
length of the private road system to the nearest public road is considered. The maximum
potential is the number of dwelling units that can possibly be served by the road when
physical barriers, zoning or other legal ccnstraints arru considered; and
8. Maintained by a capable and legally responsible owner or homeowners' association or other
legal entity made up of all benefited property owners, under the provisions of K.C.C.
19.24.050; and
9. Cfoarly dQJscribed on the face of the plat, short plat, or ether dmvelopment a~thorization and
clea~ly signed at st~eet location as a private street, for thru maintenance of which King
Ccwn.Oy is not re spans i b h.
C. King County will not accept private streets for maintenance as public streets until such streets are
brought into conformance with current County road standards. This requirement will include the hard
surface paving of any streets originally surfaced with gravel.
D. King County will not
the plat are private
in Section 2.06 8.7.
that do not meet the
accept private streets within short plats whQJn the roads providing access to
and alrQJady havru the potential to srurve more than the numb~~ of lots specified
Short :lats proposed on p~operties to which the access is ovrur private streets
standarCs in this section shall be denied.
2.07 Half Streets. See Drawing No. 1-010
A. A half street may be permitted as an interim facility when:
1. Such street shall not serve as primary access to more than 35 dwelling units or tax lots; and
2. Such alignment is consistent with or will establish a reasonable circulation pattern; and
3. ~here is reasonable assurance of obtaining the prescribed additional right-of-way from the
adjoining property with topography suitable for completion of a full-section road.
B. A half street shall meet the following requirements:
I. Right-of-way width of the half street shall equal at least 30 feet; and
2. If feasible, half street shall be graded consistent with locating centerline of the ultimate
road section on the property line; and
3. Traveled way shall be surfaced the same as the designated road type to a width not less than
20 feet, sidewalk shall be constructed as required for the designated road type; and
15
4. Property line edge of strruet shall be finished with lrumporary curbing, scouldru~s, ditchms,
and/or side slopes so as -D asscrru proper drainage, bank stabili~y, and ~~affic safety; aod
5. Half streets shall not intersect other half streets unless so approved by the Engineer.
C. When a half street is eventually completed to a whole street, the completing builder shall
reconstruct the original half street as necessary to produce a proper full-width street of
designated section.
D. The obtaining of any right-of-way or easements needed to accomplish the above shall be the
responsibility of the owning builder or developer.
2.08 Cul-de-sacs and Eyebrows. See Drawing No. 1-007.
A. Wh11,nruver a cul-de-s3c street servms morlll than six lots Jr extrunds more than 150 feet from centerline
of accessing street to farthest exhnt Jf surf3cmd travmlmd way a widened "bulb" shall be
constructmd 3s follows;
I. Minimum right-of-way diameter across bulb smction: 100 feet in a permanent. cu -de-s3c; 84
ferut in a temporary cul-de-sac, with bulb area lying oL\side straight-street right-oc-way
provided as temporary easement pending forward mxtrunsion of the strwtt. Right-of-way may bru
reduced, provided utilities and necessary drainage arm acco11111odatrud on prurmanrunt ruasements
within the development. See Section 2.19.
2. Minimum diameter of surfacing across bulb: 80 feet of paving in curb type road; 80 feet total
in shoulder type road to include 64 feet of paving and eight-foot shoulders with compacted
crushed surfacing material.
3. Cul-de-sac Island: Optional feature for any cul-de-sac when bulb paved diameter is 80 feet or
less; mandatory when bulb paved diameter exceeds 80 feet. If provided, island shall have
full-depth vertical curb. Minimum diameter shall be 20 feet and there shall be at least 22
feet of paved traveled way in a shoulder type section; 30 feet of paved traveled way in a curb
type section around the circumference. Island shall be grassed or landscaped. It shall be
maintained by the adjoining lot owners.
4. Where required on cul-de-sacs, sidewalks shall be constructed on one side and on the bulb,
terminating on a property line at or near half-way around the bulb.
B. A permanent cul-de-sac shall not bru longrur than ~oo femt measured from centerlinlll of nters~cting
street to the center of the bulb sruction. Proposrud exceptions t~ this rule will be c nsidrured by
the Engineer based on pertinrunt traffic planning nactors such as topography, sen3itiv arruas and
existing development. The cul-de-sac lrungth m3y ruxtrund to 1,000 fruet if 50 or f~wrur otential lots
are to be served and there is provision for emrurgruncy turn3round n~ar mid-langth
16
C. The Engineer or Reviewing Agency may require an off-street walk or an emergency vehicle access to
connect a cul-de-sac at its terminus with other streets, parks, schools, bus stops, or other
pedestrian traffic generators, if the need exists.
D. If a street temporarily terminated at a property boundary serves more than six lots or is longer
than 150 feet, a temporary bulb shall be constructed near the plat boundary. The paved bulb shall
be 80 feet in diameter with sidewalks terminated at the point where the bulb radius begins. Removal
of the temporary cul-de-sac and extension of the sidewalk shall be the responsibility of the
developer who extends the road. See Drawing No. J-008.
£. The maximum cross slope in a bulb shall not exceed 6 percent.
F. Partial bulbs or eyebrows shall have a minimum paved radius and an island configuration as shown on
Drawing No. J-009. Island shall be offset two feet from edge of traveled way.
2.09 Alleys and Private Access Tracts
A. An alley is considered a private road. Requirements of Section 2.03, subaccess streets, for
horizontal curvature and stopping sight distance, apply.
I. Serves a maximum of 30 lots, with a maximum length of 400 feet, no dead ends or cul-de-sacs.
2. Minimum tract width 20 feet with a pavement surface of 18 feet (including thickened edge),
based on a five-foot structure setback. For differing structure setback requirements, alley
configuration shall be designated to provide for safe turning access to properties.
3. Paved surface shall have a thickened edge on one side and cross slope in one direction. See
Drawing No. 1-011.
4. Public streets to which an alley connects or which provide access to the front boundary of the
properties served by the alley shall be 28-foot minimum paved width with vertical curb. Alley
entry shall be provided by a driveway cut.
5. Modifications to existing alleys serving commercial or industrial properties, in accordance
with the above, will be determined on a case-by-case basis subject to approval by the
Reviewing Agency.
B. Private access tracts shall conform to Section 2.03 for urban minor access roads and Section 2.06.
1. Serves a maximum of six parcels.
2. Minimum tract width of 26 feet with a maximum length of 150 feet, measured from centerline of
intersecting street to furthest extent of paved tract.
17
3. Pavement width shall be a minimum of 22 feet.
2.10 Intersections and Low Speed Curves
A. Intersections
1.
2.
3.
4.
Angle of intersection (measured at 10 feet
beyond road classification right-of-way)
Minimum centerline radius (2-lane)
Minimum curb radius
a. Urban streets and roads
cl assi fi ed neighborhood
collector or higher
b. Rural streets and roads
c. Urban residential access
street intersections where
the highest classification
involved is subcol l ector
Minimum right-of-way line radius
Minimum 85 degrees
Maximum 95 degrees
5 5 Feet
3 5 Feet
3 5 Feet
25 Feet
2 5 Feet
B. Spacing between adjacent intersecting streets, 'whether crossing or T-connecting, shall be as
fol lows:
When highest classification involved is:
Principal arterial
Minor arterial
Col 1 ec tor arterial
Neighborhood collector
Any lesser street classification
Minimum centerline offset shall be:
1,000 Feet
500 Feet
3 O O Feet
150 Feet
100 Feet
C. On sloping approaches at an intersection, landings shall be provided with grade not to exceed one
foot difference in elevation for a distance of 30 feet approaching an arterial or 20 feet
approaching a residential or commercial street, measured from future right-of-way line (extended) of
intersecting street as provided in Section 2.02, 2.03 or 2.04. See Drawing No. 5-002.
D. Entering Sight Distance. See Sections 2.02, 2.03, 2.04 and 2.12 for design requirements. See
Tables 2.1 or 2.2 for specific entering sight distance values based on required design speed.
18
E. Low Speed Curves, applicable to subaccess and minor access streets only. See Sections 2 03 and
2 04
I.
2.
3.
Minimum centerline radius (2-lane)
Minimum curb radius
Minimum right-of-way line radius
2.11 Maximum Grade and Grade Transitions
Up to 75•
100 feet
80 feet
70 feet
75• & Over
55 feet
35 feet
25 feet
A. Maximum grade as shown in Sections 2.02. 2.03, and 2.04 may be exceeded for short distances of 300
feet or less, upon showing that no practical alternative exists. Exceptions which exceed 15% w i 11
require verification by the Fire Marshal that additional fire protection requirements will be met.
Grades exceeding 12 percent shall be paved with asphalt concrete (AC) or port1and cement concrete
(PCC). Any grade over 20 percent must be PCC.
8. Grade transitions shall be constructed as smooth vertical curves except in intersections where the
difference in grade is one percent or less and upon approval of the Engineer or Reviewing Agency.
2.12 Stopping Sight Distance (SSD) applies to street classifications as shown in Sections 2.02. 203 and 2.04.
See Tables 2.1 and 2.2 for specific SSD values based on required design speed.
A Height of eye is 3.5' and height of obJect is 0.5'.
8. Minimum SSD for any downgrade averaging three percent or steeper as provided in Section 2.05. Tables
2.1 and 2.2 shall be increased by the values shown below for any downgrade averaging three percent
or steeper (Source: /IASHTO Policy on Geometric Design, Table Ill-2). Interpolate values for other
design speeds and grades.
DESIGN SPEED {MPH)
60
50
40
30
20
SSD ADJUSTMENT VALUES (FT)
DCJ/1,N'.R/{E 3 P e r c e n t
50
30
20
10
0
6 Percent
'110
70
40
20
10
9 Percent
70
30
20
C. Sag vertical curves on subaccess and minor access streets with stopping sight distance less than
that called for in Section 203 may be approved by the Reviewing Agency if no practical design
exists and if acceptable road lighting is provided throughout the curve and is maintained by a
franchised utility.
19
D. Intersecting Stopping Sight Distance.
I. Stopping sight distances for the design speeds of proposed commercial access streets,
neighborhood collector streets and arterials must be met when intersecting arterials.
2. The minimum stopping sight distance on proposed intersection approaches for all other
classifications of intersecting roadways shall be 125 feet.
2.13 Entering Sight Distance (ESD)
Entering sight distance applies on driveways and on streets approaching intersections as set forth in
Sections 2.02, 2.03, and 2.04. Entering sight distance criteria will not apply on local access streets or
minor access streets (commercial). Specific ESD values for required design speeds are listed in Section
2.05, Tables 2.1 and 2.2.
A. Entering vehicle eye height is 3.5 feet, measured from 10-foot back from edge of traveled way.
Approaching vehicle height is 4.25 feet.
B. Requirements in Section 2.05, Tables 2.1 and 2.2 apply to an intersection or driveway approach to a
typical road under average conditions. In difficult topography the Engineer may authorize a
reduction in the ESD based on factors mitigating the hazard. Such factors may include an
anticipated posted or average running speed less than the design speed or the provision of
acceleration lanes and/or a median space allowing an intermediate stop by an approaching vehicle
making a left turn.
C. Where a significant number of trucks will be using the approach road, the Engineer may increase the
entering sight distance requirements by up to 30 percent for single-unit trucks and 70 percent for
semi-trailer combinations.
2.14 Medians (Optional Design Feature)
Median width shall be additional to, not part of, the specified width of traveled way. Edges shall be
similar to outer road edges: either extruded or formed vertical curb; or shoulder and ditch; except that
median shoulders shall be minimum four feet in width. Twenty feet of driveable surface (which includes
traveled way and paved shoulders, if any) shall be provided on either side of the median. Median may be
grassed, landscaped, or surfaced with aggregate or pavement. Median shall be designed so as not to limit
turning radii or sight distance at intersections. No portion of a side street median may extend into the
right-of-way for an arterial street. The Engineer may require revisions to medians as necessary to
provide for new access points and to maintain required sight distance. Non-yielding or non-breakaway
structures shall not be installed in medians. Street trees may be planted in median subject to approval
by the Engineer.
20
2.15 One-Way Streets
Local access strruets, including loops, may be designated one-way upon a finding by the Engineer that
topography or ohrur sitm features make two-way traffic impractical.
2.16 Bus Zones and Turn-Outs
During the design of arterials and neighborro~d col lructors, the designer shall contact Metro Service
Planning, phone 684-1622 and the local schoO' district to determine bus zone (stop) locations and other
bus operation needs. The road project shal I provide wheel chair accessible landing pads at designated bus
zones as per Section 3.02 of the Standards and where required shall include turn-outs and shelter pads.
Pedestrian and handicapped access improvruments within the right-of-way to and from the bus loading zone or
turn-out from nearby businesses or residences shall also be provided as part of the road improvement.
Surfacing requirements may also be affected, particularly on shoulders. See Section 4.0lB of the
Standards. Metro's publication, ''Metro Transportation Facility Design Guidelines," is applicable.
2.17 Exception to Paving on Rural Minor Access Streets (Residential)
A. A rur3l minor access strrurut (rmsidrunti3l) as ~ruscribrud in Section 2.03 that is a private street
shall mmet the following standard: It sh3ll ~ru graded and, as minimum treatment, be surfaced full
width including shoulders (28 feet) with crus~ed swrf3cing material as provided in Section 4.0lA
Altrurn3tive V and Drawing No. 1-004 Half streets sh3ll be surfaced not less than 20 feet wide.
Whrure connecting to a public street the comnecting area shall be paved between traveled way and
right-of-way linw (extended} of the public strruet, with 25 foot or 35 foot radii as required by
Section Z.10. P3ving shall bruin accordance •Ith Section 4.0lA with applicable alternative other
than Alternative V.
B. Any rural minor access street (residential) approved undmr subsruction A above shall remain a private
street unless it is upgraded to public strerut s03nd3rds 30 the exprunsm of the subdivider or
adjoining lot owners, to include hard surf3cru p3ving, anc 3cceptmd by the Engineer for public
ownership and maintenance.
2.18 Intersections with State or Federal ~ighways
In thru event th3t thm Co~nty has jurisdiction on a development that requires the construction or
improvement of 3 commerc~al/industrial driveway or any classification of street that intersects a state or
federal highway, minimum.intersection spacing, entering sight distance and landing requirements in
3ccord3nce with these Standards shall be satisfied in addition to the requirements of all other applicable
permits. In thru insta~ce State or Federal standards exceed these Standards, State or Federal standards
sha 11 govern
21
2.19 Slope, Wall. & Drainage Easements and Right-of-Way Reduction
A. Easements
Either the functional classification or particular design features of a road may necessitate slope.
sight distance, wall or drainage easements beyond the right-of-way line. Such easements may be
required by the Engineer or Reviewing Agency in conjunction with dedication or acquisition of
rig ht-of-way.
B. Right-of-way reduction on subcollectors. local access (residential) and minor access (commercial)
In proposed developments served by underground utilities within easements. the right-of-way may be
reduced to the minimum roadway width plus sidewalk, as allowed in Sections 2.03 and 2.04. with the
approval of the Reviewing Agency. Where it is desired to reduce right-of-way to a minimum width,
the right-of-way. plus easement. shall allow for construction and maintenance of the following as
appropriate, sidewalks, planter strips. drainage facilities. sign placement. and also allow sidewalk.
widening around mailbox locations. Oi subcollectors. installation of fixed objects. other than
required above ground utility structures. greater than four inches in diameter within four feet of
back of sidewalk shall not be permitted.
2.20 Access and Circulation Reauirements
In order to provide a second access to a residential subdivision. short subdivision, binding site plan or
planned unit development, no residential street shall serve more than 100 lots or dwelling units unless
the street is connected in at least two locations with another street that functions at a level consistent
with Sections 2.02 and 2.03.
A The second access requirement may be satisfied through use of connecting a new street to an existing
street in an adjacent neighborhood if:
1. i'k.J other practical alternative exists, or
2. Existing street was previously stubbed indicating intent for future access. or
3. M easement has been recorded specifically for said purpose.
The second access requirement may not be satisfied through use of an existing roadway network in the
existing adjacent neighborhood if:
1. A more practical alternative exists, or
2. Existing streets do not meet Section 203
These provisions are not intended to preclude the state statute on land-locking.
B. This section does not preclude a commercial project from gaining access :hrough a residential
development. Traffic rnpac:s for suc:1 p::ojects will be analyzed during :he SEPA process.
2.21 Exception for MaximuIT. Dwelling Cnits on •:rban Subcollectors
Proposed sc.bcollectors serving new ·J::ban area deve1.op11•.er_ts with a_, average density of seven to eight
dwelling units per acre and which meet: the access ;:equirements of Sec:ion 2.20 may serve un to 250 single-
family dwelling un:.:s, if approved by the Reviewing Jl.ger.cy. Frioc to approval, the Reviewing Agency may
recpire a traf:"ic ciccula:ion study showing a balanced traffic flow of less than 1500 vebcles ner day
past any access point. Street trees s:1a~l be mardatcry along SJbccllectors servi:-ig higter dens:_t:.es of
seven to eight dwelling units per acre and shall be in codormance wi:h Section 5.03.
23
CHAPTER 3. DRIVEWAYS WALKS. &. TRAILS
3 01 Driveways
A. Dimensions, slope, and detail shall be as indicated in Drawings No. 2-001. 3-003. 3-004. 3-005 and
3-006, as further specified in the following subsections. See Section 2.13 for entering sight
distance requirements.
B. Conditions for Approval of New Driveways:
1. Driveways directly giving access onto arterials may be denied if alternate access is
available.
2. Al I abandoned driveway areas on the same frontage shall be removed and the curbing and
sidewalk, or shoulder and ditch section, shall be properly restored.
3. Maintenance of driveway approaches shall be the responsibility of the owner whose property
they serve.
4. For a commercial establishment on a shoulder and ditch type road, where development of
adjoining lands and highway traffic assume urban characteristics as determined by the
Reviewing Agency, the frontage shall be finished with curb. gutter, and sidewalk, with pipe
drainage. all in accordance with these Standards. Alternatively, the Reviewing Agency may
5.
require the entire frontage area to be graded and paved to the right-of-way line with asphalt
or portland cement concrete. In such case, surface drainage shall be intercepted and carried
in a closed system as set forth in Chapter 7. Access shall be limited by means of a six-inch
curbing. See Extruded Asphalt or Cement Concrete Curb detail, Drawing No. 3-002.
For driveways crossing an open ditch section. culverts shall be adequately sized to
anticipated stormwater flows and in no case be less than 12 inches in diameter. The
owner making the installation shall be responsible for determining proper pipe size
Reviewing Agency may require the owner to verify the adequacy of pipe size.
carry
property
The
C. Location and Width of NeN Driveways. Refer to Drawing No. 3-006.
1. A residential driveway shall typically serve only one parcel. A driveway serving more than
one parcel shall be classed as a commercial driveway or a private street, except as provided
in 3.a. and 3.b. below.
2. 01 frontages 75 feet or less, no more than one driveway per lot shall be constructed: on
frontages over 75 feet. two or more driveways per lot may be permitted, subject to approval by
the Reviewing Agency
3. No portion of driveway width shall be allowed within 5 feet of side property lines in
residential areas or 9 feet in commercial areas except as follows:
a. A joint use driveway tract may be used to serve two parcels:
(I) Minimum tract width in urban areas shall be 20 feet with an 18 foot paved surface,
cross slope in one direction and curb or thickened edge on one side. Minimum
tract length shall be 20 feet from right-of-way line. Radius returns on paved
apron shall have JO-foot radii.
(2) Minimum t~3ct width in rliral 3reas shall be 20 forot; 30 feet if a ditch is
req"ired. Minimum tract lrong"h shall be 20 feet o,om right-of-way line. Radius
retlirns on p3ved 3pron sh3ll ,3ve JO-foot radii.
(3) Driving surface (rural areas) shall be 18 feet, paved or gravel, with a paved
apron from the edge of pavement of intersecting street to right-of-way line.
(4) The Reviewing Agency may allow use of an easement if the only access to a serving
roadway is through an adjace,t parcel not owned by the applicant or for urban
residential short plats to s3tisfy minimum lot width requirements.
b. Driveways may utilize full width of narrow "pipe-stem" parcels or easements if approved
by Reviewing Agency.
c. On cul-de-sac bulbs as necessary for proposed residential access.
4. Grade transitions, oixcluding the tie tc the roadway, shall be constructed as smooth vertical
curves. Ties to the roadw3y shall bm constructed as shown in Drawings 3-003 and 3-004. The
maximum change in driveway grade, within the right-of-way, shall be 8% wilhin any 10 feet of
distance on a crest and 12% within any JO feet of distance in a sag vertical curve. Driveway
shall be graded to match into possible future widened road section without encroachmront into
graded shoulder or sidewalk. The design engineer for proposed developmoints shall consider the
access driveway profile when designing the serving road to ensure that recuired gr3de
transitions can be complied with considering building set back and lot te~rain coocitions.
5. Driveways in rolled c~rb sections may bro ccnst,uctrod abutting and flush with sidewalk or back
of curb without g3p~ing or b•m,ing hoiight cf cu,b.
D. Existing driveways may be reconstructed as they exist provided such reconstruction is compatible
with the adjacent road.
E. For cornmoirci 31 o, indust,i al dri ve-3ys with he3vy t,3ffi c vol urnes or significant numJ~,s cf .1,ucks,
thm Rmviewinq Agmncy m3y rroquire construction of the 3ccess as a ,03d inte,section. I Ois
25
F.
requirement will be based on traffic engineering analysis submitted by tWe applicant that considers
among other factors, intersection spacing, sight distance and traffic volumes.
Notwithsta~ding 3ny other ]r<ovisions, driveways will not be al lowed where they are prohibited by
separate C0 unty council ac.Oicn or< where they are determined by the Engineer or Reviewing Agency to
create a h3zard er impedm the operation of traffic on the rc3dway.
3.02 Concrete Sidewalks
A. Shall be required on urban category, curb and gutter type streets as follows:
1 On all arteri3ls, neighborhood ccllectcrs, subcollructors, multiplm'1Jwelling 3rnd businmss
access sOrmmts, both sides.
2. On subaccess streets and industrial access streets, one side.
3. On minor access streets {commercial), both sides unless alternative routes are provided for
pedestrians.
4. On minor accrnss strmmts (residenti3l) exceeding 50 feet and on any cul-de-sacs with
off-street W3l k...ays extending from their tmrmi ni to other strmruts, parks, schools, bus stops,
or other pedestrian traffic generators, onm side. On cul-de-sacs, sidewalks shall extend
around bulb to intrursect off-street walkw3y. Other ruxtended off-street walkways may be
required by t~e RruVimwing Agency to provice dirmct connections for ease and safety of
pedesOri ans.
B. Shall be constructed:
1. Next to the curb unless planting strips 3rm part of thru dmsign 3rnd 3re approved by the
Engineer as part of a landscaping plan.
2. Back of planting strips where planting strips are to be constructed.
3. At least five feet widm on rrusidential and commercial accruss strruets. This mmans fivm feet
clear of mailboxes o, othrur obstructions, except wherru 3p1roved as a variance. Width shall be
minimum six and onru-Galf neet on arbrials if curb is nillx0 to traveled Done {but not necessary
next lo designated parking or bike lanws). The addition3l width, one anc one-half feet or
more, may bru finished to match the sidwwalk ~r may be finished with contnsting textur(l),
asphalt concrrute, brick, or paving blocks as approved by 1.hm Rruviewin3 Ag,ncy or Enginmer.
4. At least eight feet wide:
a. In business/commercial districts where most of the store frontage is within 80 feet of
the street right-of-way.
26
b. Within the curb radius returns of all arterial intersections where curb ramps are
required.
c. Within designated bus zones to provide a landing area for wheel chair access to transit
services.
5. With specified width greater than eight feet where Engineer or Reviewing Agency determines
this is warranted by expected pedestrian traffic volume.
6. With portland cement concrete surfacing as provided in Sections 3.03 and 4.01. See
specifications for joints in Section 3.04 and Drawing No. 3-001.
3.03 Curbs, Gutters and Sidewalks
A. Subgrade compaction for curbs, gutters, and sidewalks shall meet a minimum 90 percent of maximum
density.
B. Concrete for curbs, gutters, and sidewalks shall be Class 3000, furnished and placed in accordance
with WSDOT/APWA Standard Specifications, Sections 6-02, 8-04, and 8-14. Cold weather precautions as
set forth in WSDOT/APWA Standard Specifications Sections 5-05.3(14) and 6-02.3(6)A shall apply.
C. Extruded cement concrete curb shall be anchored to existing pavement by either steel tie bars or
adhesive in conformance with WSDOT/APWA Standard Specification Section 8-04.
D. Extruded asphalt curbs shall be anchored by means of a tack coat of asphalt in accordance with
WSDOT/APWA Standard Specification Section 8-04.
3.04 Expansion and Dummy Joints. See Drawing No. 3-001.
A. An expansion joint consisting of 3/8" or 1/4" x full depth of premolded joint material shall be
placed around fire hydrants, poles, posts, and utility castings and along walls or structures in
paved areas. Joint material shall conform to the requirements of ASTM D994 (AASHTO M33).
B. A dummy joint consisting of 3/8'' or 1/4" x 2" of premolded joint material shall be placed in curbs
and sidewalks at a minimum of 15 foot intervals and at sides of drainage inlets. When curbs and/or
sidewalks are placed by slip-forming, a premolded strip up to 1/2" thick and up to full depth may be
used.
C. Dummy joints in sidewalk shall be located so as to match the joints in the curb whether sidewalk is
adjacent to curb or separated by planting strip.
D. Tool marks consisting of 1/4" V-grooves shall be made in sidewalk at five foot intervals,
intermediate to the dummy joints.
27
E. f!,.s alternative to expansion Joints around structures. reinforcing bars may be embedded in concrete
on four sides of structures.
F. Interface between curb and adjacent sidewalk on integral pour construction shall be formed with J/4"
radius edging tool. 01 separate pour construction an expansion Joint consisting of 3/8" or 1/4" x
full depth of premolded joint material shall be placed between the curb or thickened edge and the
adjacent sidewalk.
3 05 Curb Ramps
01 all streets with vertical or rolled curb, ramped sections to facilitate passage of handicapped persons
shall be constructed through curb and sidewalk at street intersections and other crosswalk locations. See
Drawings No. 4-002 and 4-003. Where a ramp is constructed on one side of the street, a ramp shall also be
provided on the opposite side of the street. Curb ramps shall be positioned so that a ramp opening is
situated within the marked crosswalk or crossing area if unmarked.
3.06 Concrete Steps, Metal Handrail and Handicapped Access Ramps
A. Steps shall only be used where acceptable alternative access is available for handicapped access and
there is a need for a separate stairway. Where used, concrete steps shall be constructed in
accordance with Drawing No. 5-008 or other design acceptable to the Engineer or Reviewing Agency and
consistent with the WSDOT/APWA Standard Specifications Handrails, whether for steps or other
applications, shall be provided consistent with Drawing No. 5-008 and the WSDOT/APWA Standard
Specifications
B. Ramps used to provide handicapped access shall have a maximum slope of 12:1 with a maximum rise of
30 inches between landings. Landings shall have a minimum length of five feet and should be of
sufficient width to allow wheelchairs to pass, generally five feet minimum width for two way
traffic.
3.07. Asphalt Shoulders
A. In urban areas, asphalt paved shoulders may be used where approved by the Engineer or Reviewing
Agency on existing roads to provide for bicycle and pedestrian use as specified In Section 1.038 and
to provide continuity of design. When allowed. paved shoulders shall be placed in conformance with
.Sections 2.02 and 2 03.
B. In rural areas, asphalt paved shoulders which may serve as walkways and bikeways, shall be provided
on both sides of any arterials or other roads designated in the King County Nonmotorized
Transportation Plan or as directed by the Engineer or Reviewing Agency.
C Where shoulders are paved on one side only, they shall be delineated by a four-inch white
thermoplastic edge line.
3.08 Separated Walkways, Bikeways and Trails
Separated P"d"strian, bicycle and "qu,.strian trails shall b• provided where designated in community and
function3l pl3ns or where required by the <ngineer or Reviewing Agency because of anticipated significant
public w3age. Separated facilities are typically l 0 cated on an <asement or within th" right-of-way when
separatec from the roadway b~ a drai11age ditch or b3rrier. Wha,re separate walkways, ~ikeways, or
equestri3~ trails in,,.rsect With motorized traffic, sight•· stance, marking and sign31ization (if
warrautecl shall be as praviC:ed in MUTCD. Faciliti"s sha17' be designed as follows:
A. Separated asphalt walkways are
the right-of-way or easement.
in Section 4.010.
designed primarily for pedestrians and are typically located within
Minimum width shall be five feet with asphalt surfacing as indicated
B. Neighborhood pathways are so ft surf3ce f3c i l it i es designed for pedesfr i ans a-d equestrians. Such
pathways shall be a minimum four fe,.t Wice with at least one and one-Oalf ;;0°t clearance to
obstructions on both sides and 10 foot vertical clearance. Pathways shall be, designed and located
so as to avoid drainage and erosion problems. Pathways shall be constructed c;; two and on~-half
inches of crushed surfacing top course or wood chips over cleared nativc mata,~ial as approved by the
Reviewing Agency.
C. Multi-purposru trails are ty~ically designated for bicycle and pedestrian ws" and in general ~ollow a
right-of-way indep~ndent frooi any road. Multi-purpose trails sh3ll b~ design~d to bic::,cle path
standards as describrud in SDction 3.10.
3.09 School Access
School access required as part of development approval shall be provided by an asphalt walkway, concrete
sidewalk or fwll width delineated shoulder unless another alternative is available and approved by the
Engineer through a road variance request.
3.10 Bikeways
A. 3ikeways ar~ generally shared with other transportation modes, although they may be providDd
exclusively for bicycle use. Bikeways are categorized below based on degree of separation from
moto~ v~hicles and other transportation modes. This classification does not denote pr~fereuce cf
one ()_fvpe over another. Bikeways are categorized as follows:
Bike Path (Class!): A se-uarate
other nonmotori2ed mC<les.
should be 12 ~eet wi~.
paved multipurpose trail for the principal use of bicycles and
Bike paths are 10 feet wid> except in high usage areas where they
Bike Lane (Class II): A portion of the road that is designated by pavement striping for exclusive
bicycle use. Bicycle lanes may be signed as part of a directional route system. Bicycle
lanes are five feet wide on a curbed road and minimum four feet wide as a shoulder bike lane
29
Wide Curb Lane (Class Ill): A road that provides a widened paved outer curb lane to accommodate
bicycles In the same lane as motor vehicles. Lane width shall be increased at least three
feet
Shoulder: A lane contiguous to the traveled way but separated by a stripe. Most oomrmn in rural
areas. Typically shared with pedestrians and occasional emergency vehicle access.
Shared Roadway: Al I roads not categorized above where bicycles share the roadway with motor
vehicles.
B. A bikeway shall be provided:
1. Wherever called for in the Nonmotorized Transportation Plan. King County Transportation Plan.
King County Comprehensive Plan. community plan, Capital Improvement Program or Transportation
Needs Report.
2. VVl'er1 substantial bike usage is expected which would benefit from construction of a bicycle
facility.
C Striping and signing shall be implemented as follows
1. Pavement markings shall be used on bike lanes and paths according to MUTm.
2. The design of a 11 signalized intersections shall cons'ider bicycle usage and the need for
bicyclists to actuate the signal.
D. The planning and design of bikeways in any category shall be In accordance with Section 1020 of the
W'IXJT Design Manual and the AASHTO Guide for the Development of Bicycle Facilities, current edition.
3.11 Equestrian Facilities
A. Equestrian facilities adjacent to the traveled way shall be provided where proposed by the King
County Nonmotorized Transportation Plan or as required by the Engineer or Reviewing Agency.
Facilities shall be provided as follows
1. Shoulders adjacent to the traveled way intended for equestrian use shall be surfaced
full-width. minimum four feet with eight feet desirable. Surface shall be two and one-half
inches of crushed surfacing base course and one and one-half inches of crushed surfacing top
course.
2. A seua:ated equesL'.an trail shall be cc:is:ructed with a:i 18 perce:it maximum grade, :D-fcct
ve:::dcal clear2nce and a five-foot wide pathway zone. The trail shall be consLucted of
ra:i ve soil or, where drair.age or ercs'.on problems are present, a mir.imurr. of two ar.d one-hd f
inches of crusied surfaci:ig top course or. graded and co11pacted native soil. Na:ive scil whic"1
is no: free draining sha~l :Je removed anci replaced with free d:::aining soil as necessary to
provide a maintainable a:id well -dra'.ned subgrade, Additional crushed su:facing, cinders or
other stabilizir.g mate:ials sr.all be :::ec:uired if heavy usage '.s anticipa:ed or if t:1ere is any
evidence cf instability '.a the subgrade; ir.ckdi:ig-free watec, swamp conditic:is, fine-g:::ained
or orgaric sc'.ls, s:'.des or uneven :ra'.ls.
CHAPTER 4. SURFACING
4.01 Residential Streets, Pedestrian and Bike: Th* minimum paved section, with ajlernative combinations of
materials, for residential stre*t,, shoulders, sidew3lks and bikeways shall Je aj indica 0 ed below. These
sections arru acceptablm only on v;sually good, well-crained, stable compacte: suigrade. Any proposed
exception Go these m3trurials will be subject to soils strength trusting and traff,c loading analysis and
subject lo rruview anc approval by the Enginerur as outlined in Section 4.02 brulow. All expenses for
determinim revis~d materia Is shall be borne by the Developer.
TYPE OF FACILITIES
A. RESIDENTIAL ACCESS STREETS
Alternative I
Alternative I I
Alternative I II
ASPHALT
CONCREH.:
2"(3"*)
2"(3"*)
(Acceptable for rural areas,
transitional areas, and design3ted
agricultural production districts
only, on grades not steeper tH3n
12 percent)
Alternative IV
Alternative V
(Acceptable on rural minor
access streets) . . . .
*On neighborhood collructors
B. SHOULDERS
Alternative I
Alternative II
Alternative III
Alternative IV
*On bus routes
C. SIDEWALKS
Alternative I
(Acceptable except behind
rolled curb)
2" (3"*)
2" (3"*)
ASPHALT
TREATED
BASE
4"
4"
32
BITUMINOUS
SURFACE
IREATM~tH
Class A
Class A
CRUSHED
SURF. TOP
(OURSE
l i I!
ll"
ll"
ll"
It"
]j"
CRUSHED
SURF. BASE
COURSE
. 5"
.511
2!"
Zi II
ZJ"
Zj"
PORTLAND
CEMENT
CONC_R[TE
Class 4000.
7" (8"*)
Class 3000, 4"
1YPE CF FACILITIES
Alternative II
ASPHALT
CQ\lffiETE
ASPHALT
TREATED
B/lSE
BITUMINOUS
SURFAOE
TREATMENT
ffiJSI-ED
SURF. TCP
CD.RE
CRLGHED
SURF. B/lSE
CD.RE
PORllPND
ffilB\!T
cx:::N'.RETE
(Mandatory behind rolled .......... Class 3000, 5"
curb) · · · · · · · · · · · · · · · · · · ·
D. Wr,mft/AYS & BIKEWAYS
Alternative I
Alternative II
Alternative Ill
Alternative IV
Alternative V
2"
3 l"
Class A . ....
(may be used as shown on DNg. No. 1-005 and
1-006 or where approved by Reviewing Agency).
ll"
ll"
2"
2 ! "
2 i LI
. Class 3000, 5"
Wren a walkway or bikeway is incorporated into a road shoulder, the required shoulder section, if higher
strength, shall govern. Subgrade compaction for bikeways and paved walkways shall meet a minimum of 90
percent maximum density.
E. DRIVEWAYS may be surfaced as desired by the owner, except:
1. On curbed streets with sidewalks, driveway shall be paved with portland cement concrete Class 4000
from curb to back edge of sidewalk. See Drawings No. 3-004 and 3-005.
2. On shoulder and ditch section, driveway between edge of pavement and right-of-way line shall be
surfaced as required by Drawing No. 3-003.
3. On thickened edge roadways with underground utilities, portland cement concrete may be used for
driveways between the thickened edge and the right-of-way line provided that a construction joint is
installed at the right-of-way line.
F. STREET WIDENING/ADDING TRAVELED 1/1/'¥ TO EXISTING FU'\JJS
1. V'vten an existing asphalt paved street is to be widened, the edge of pavement shall be saw cut to
provide a clean, vertical edge for Joining to the new asphalt. After placement of the new asphalt
section, the joint shall be sealed and the street overlaid one inch, plus a pre level course, fu 11
width throughout the widened area. The requirement for overlay may be waived by the Engineer or
Reviewing Agency based on the condition of existing pavement and the extent of required changes to
channelization.
2. When an existing shoulder is to become part of a proposed tr3veled way 3 ~avement evaluation shall
be performed. This evaluation shall analyze the structur3l capacity a11c Cetermine any need for
improvement. Designs based on these evaluations 3re subjruct to review and approval by the Engineer
or Reviewing Agency. The responsibility for any shoulder material thicknruss improvement shall be
considered part of the requirement for roadway widening. The sho11ldru~ sh31 l be replaced in width as
specified in Sections 2.02, 2.03 and 2.04.
3 Any widruning of an ruxisting -oadww, ruithrur· b add .~r3velrud W(J.l a~ pavmd shculdm~ shall h3vm thru
same s11~f3cing rntillrial 3S tom exis~iri~ rc3dway.
4.02 Requirements for Residential Streets on Poor Subgrade
The minimum material thicknesses indicated in Section 4 01 are !JOi acceptableif I.here is 3ny evidencru of
instability in the subgrade. This includes fre~ water, swamp conditions, fineg rained or organic soi ,
slides or uneven settlement. If there are any of these characteristics, the g:j l shall be sampled an
tested sufficiently to establish a pavement design that will support the proposed construction. Any
deficiencies, including an R value of less l.h3n 55 er a CBR of less than 2C, shall be fully considered in
the design. Remedial measures may include, but are not limited to, 3 stronger paved section, a
strengthening of subgrade by adding or substituting fr3ctured ag3reg3te, asphalt trru3ted base, nsta ling
a geotextile, more extensive drainage or a combination of such mtcasures. Both the soils test r port and
the resulting pavement design will be subject to review 3nd approval by th~ Enginerur or Reviewi g Agency.
4 03 Arterials and Commercial Access Streets
Any pavement for arterials and commercial access streets shall be designed using currently accepted
methodology that considers the load bearing capacity of the soils and the traffic-carrying requirements of
the roadway. Plans shall be accompanied by a pavement thickness design based on soil strength parameters
reflecting actual field tests and traffic loading analyses. The analysis shall include the traffic volume
and axle loading, the type and thickness of roadway materials and the recommended method of placement.
Pavement sections shall not be less than those required for neighborhood collectors .
. 04 Materials & Lay-Down Procedures: Shall be in accordance with WSDOT/APWA Standard Specifications and the
following requirements:
A. Crushed surfacing top 3nd b3se courses m(J.l be substituted for a structurally equivalent thickness of
ATB. The substitution r3tio of crushed surfacing to ATB shall be 1.6:1. Where base or top courses
c3nnot be placwd without possiblru contamination, then thruse ccurses shall be substituted by ATB.
B. During surfacing activities utility covers in roadway shall be adjusted in accordance with Section
8.04.
C. ATB may be used over isolated areas of unstable subgrade, providing the final lift of asphalt shall
not be placed for a minimum of six months to allow time for the observation and repair of failures
in the subgrade and ATB.
34
D. Asphalt pavers shall be self contained, power propelled units.
considered self propelled. Truck mounted pavers shall only be
or minor areas as approved by the Engineer, or as follows:
1. pavement widths less than eight feet; and
2. pavement lengths less than 150 feet.
4.05 Pavement Markings, Markers, and Pavement Tapers
Truck mounted type pavers are not
used for paving of irregularly shaped
Pavement markings, markers or striping shall be used
and longitudinal lines to control or guide traffic.
approved by the Traffic Engineer.
to delineate channelization, lane endings, crosswalks
Channelization plans or crosswalk locations shall be
Channelization shall be required when through traffic is diverted around a lane or obstacle; and when
connecting full width streets with different cross sections; and when extending an existing street with a
new cross section different than the existing one. The channelization shall provide tapers equal in
length to the posted speed limit times the distance in feet of diversion from the road centerline or the
original alignment of travel, or the offset distance, as applicable. Channelization shall also be
required to redirect traffic back to their original alignment.
Left turn channelization shall include a minimum of 150 feet of full width lane to include storage and a
reverse curve 90 feet in length for posted speeds up to 45 mph. The reverse curve shall be 120 feet in
length for posted speeds greater than 45 mph. The reverse curve may be included within the taper
distance. A deceleration taper as shown in the WSDOT/APWA Standard Plans may be used in place of a
reverse curve. Standard left turn lanes shall be 12 feet wide. Type 2L arrows shall be installed in the
lane 25 feet and 100 feet behind the stop bar, crosswalk or stopping area. Additional storage may be
required for long vehicles or anticipated left turn queues longer than the minimum storage.
Centerline for channelization shall consist of two four-inch yellow lines with a four-inch separation.
Type 2d lane markers shall be installed at 40 foot centers between the lines. Holding lines for
additional lanes shall be eight-inch white lines with Type 2e lane marker on the inside of the lane at 20
foot centers. Edgelines for tapering thru traffic back to the original alignment shall consist of four-
inch white lines.
Pavement markings for channelization shall be reflectorized hot or cold applied plastic. Extruded or
sprayed markings shall be dressed with glass beads for initial reflectance. All materials shall have
beads throughout the material to maintain reflectance while the material wears.
Where pavement widening less than 300 feet in length is abruptly ended and edge lines do not direct
traffic to through lanes, Type 2e lane markers shall be installed at 10 foot centers near the end of the
paved area at a 10:1 taper.
35
Crcsswalks sha~l be installed at all
by the Traffic Engineer. Crosswalks
fee: and with eig;~t-inch separaLcn.
the whee~ tracks :.n ead: lar.e anci a:
i:itersectior.s c::m:roLec: by :raff:.c sigr.a 1 s ad otr_er areas a.pp::oved
shall cms:cs: of se:s of longituciinal lir.es e:.cf1t inches wide by lU
A se: of :hese ::.nes sb:l: be installec: between eac'1 lane, between
L1e pavement edges.
i\11 paveme:it markings s:iall be laid ou: with spray pane a:id appro•:ed :iy be :'ra.:Lc E'lc:i:1eer befc1·e t:iey
are installed. A.pproval may require 2 :hree wcrki:ig ciay acivance rntice to :1ave :ield lay-od apornved b;
:Le Traffic ~ngir,eer or to make arrangements to meet :he :'::a""ic E:19:.r.ee::: o:" si:.e dl:r'ng the ir:sta~latim.
CHAPTER 5. ROADSIDE FEATURES
5.01 Rock Facings
A. Rock facings may be used for the protection of cut or fill embankments up to a maximum height of
eight feet above the keyway in stable soil conditions which will result in no significant foundation
settlement or outward thrust upon the walls. Smm Drawing Nos. 5-004 throwgh 5-006. For mei3hts
over eight feet above the keyway or when soil is unstable, a structural wall of acceptablru drusign
shall be used. As an exception, rock facing heights may exceed eight feet to a limited extent based
on favorable soils analyses and a design by a geotechnical enginerur or othmr professional engineer
qualified in rock wall design, subject to approval by the Engineer. Tmrracing of rockerirus subject
to approval by the Engineer.
B. Materials
1. Size categories shall include:
Two-man rocks (200 to 700 pounds), 18"-28" in average dimension;
Three-man rocks (701 to 2000 pounds), Z8-36" in averagru dimension; and
Four-man rocks (2001 to 4000 pounds), 06-48" in averagru dimension.
Four-man rocks shall be used for bottom course rock in all rock facings over six feet in
height.
2. The rock material shall be •s nearly rectangular as possible. No stone shall be used which
does not extend through the wall. The quarried trap rock shall be hard, sound, durable and
free from weathered portions, seams, cracks and other defects. The rock density shall be a
minimum of 160 pounds per cubic foot, measured according to WSDOT Test Method 107 (Bulk
Specific Gravity -S.S.D. basis). Additionally, rock subjected to the U.S. Army Corps of
Engineers Test Method CRD-C-148 ( "Method of Testing Stone for Expansive Breakdown on Soaking
in Ethylene Glycol") must have less than 15 percent breakdown.
C. Keyway
A keyway consisting of a shallow trench of minimum 12-inch depth shall be constructed t"e full
rockery length, and slightly inclirned towards the face being protected. It shall be ruxcavatrud the
full rockery width including the reek filter layer. The keyway subgrade shall be firm 3nd
acceptable to the engineer. See Drawing No. 5-004.
D. Underdrains
1. A minimum six-inch diameter perforated or slotted drain pipe shall be placed in a shallow
excavated trench located along the inside edge of the keyway. The pipe shall be bedded on and
surrounded by "Gravel Backfill for Drains" (WSDOT/APWA 9-03.12(4)) to a minimum height of 18
37
inches above bottom of pipe. A filter fabric shall surround the gravel backfill and shall
have a minimum one-foot overlap along the top surface of the gravel. This requirement for
fabric may be waived by the Engineer if shown that soils and water conditions make it
unnecessary. See Drawing Nos. 5-004 through 5-006.
2. The perforated pipe shall be connected to the storm drain system or to an acceptable outfall.
E. Rock Selection and Placement: Rock selection and placement shall be such that there will be m1n1mum
voids and, in the exposed face, no open voids over six inches across in any direction. The final
course shall have a continuous appearance and be placed to minimize erosion of the backfill
material. The larger rocks shall be placed at the base of the facing so that it will be stable and
have a stable appearance. The rocks shall be placed in a manner such that the longitudinal axis of
the rock shall be at right angles to the face. The rocks shall have all inclined faces sloping to
the back of the facing. Each course of rocks shall be seated as tightly and evenly as possible on
the course beneath. The rocks shall be placed so that there are no continuous joint planes either
horizontally or vertically. After setting each course of rock, all voids between the rocks shall be
chinked on the back with quarry rock to eliminate any void sufficient to pass a two-inch square
probe. See Drawing Nos. 5-004 through 5-006.
F. Rock Filter Layers: The rock filter layer shall consist of quarry spalls with a maximum size of
four inches and a minimum size of two inches. This material shall be placed to a 12-inch minimum
thickness between the entire facing and the cut or fill material. The backfill material shall be
placed in lifts to an elevation approximately six inches below the top of each course of rocks as
they are placed, until the uppermost course is placed. Any backfill material on the bearing surface
of one rock course shall be removed before setting the next course.
G. Fill Rockery Facing Supporting Roadway Embankment: Embankment behind rockeries exceeding four feet
in height above the keyway shall be reinforced with a geosynthetic fabric or geogrid specifically
manufactured for soil reinforcement, designed on a project specific basis by a qualified engineer.
See Drawing No. 5-007.
H. Sidewalks Above Rockery Facings: When a sidewalk is to be built over a rock facing, the top of the
facing shall be sealed and leveled with a cap constructed of cement concrete Class 3000 in
accordance with the applicable provisions of Section 6-02 of the WSDOT/APWA Standard Specifications,
but with reduced water content resulting in slump of not over two inches. See Drawing No. 5-006.
I. Fences and Handrails
A chain link fence or metal handrail shall be installed when rockery is three feet or greater in
height. (See Drawing Nos. 5-004 through 5-006 and 5-008)
38
5.02 Side Slopes
A. Side slopes shall general~y be constrwcted no steeper Lh3n 2:1 on both fill slopes and cut slopes.
Steepe~ slopes may be 3pproved by the Engineet< Ul)on showin3 that the stee1Jet< slol)es, based on soils
3nalyses, will be sta(l)le. Side slopes on projmdls funded "Y fadenl gran:~s shalT be constructed in
conformance with Locai Agency G,,idel ines.
B. Side slopes shall be stabilized by grass sod or seeding or by other planting or surfacing materials
acceptable to the Engineer.
5.03 Street Trees & Landscaping
A. Street trees and landsc3ping shculd be incorporatllld into the design of rD3d improvements fer all
classifications of roads. Such landsc3ping in thlll right-of-way shall be coordinated with off-stree
landscaping required on deve l opa,r' s propet<ty under the provisions of King County Code Ch3ptrur 21. 51
B. Planting strips arm ol)tion3l along all classifications of roads and may be considered as part of the
landscape mitigation requirements established during the SEPA review process. The design of
planting strips must lJe approved by the Engineer and must include a landscaping plan in which plant
maintenance, utilitims and traffic safety requirements are discussed.
C. Existing trees and landscaping shall be preserved where desirable and placement of new trees shall
be compatible with other features of the environment. In particular, maximum heights and spacing
shall not conflict unduly with overhead utilities, or root development with underground utilities.
If street tt<ees are planted, they shall conform reasonably to standards in Drawing No. 5-009.
D. New trees shall not include ~oplar, cot0onwood, soft m3ples, gum, any fruit bearing trees or any
other tree or shrub whose roots are like7y to obstruct sanitary or storm sewers. See King County
Code 13.04.230.
E. Street tree plans on bus routes shall be reviewed by Metro Service Planning, phone 684-1622.
5. 04 Ma ii Boxes
A. The responsibilities for location and installation of mailboxes in connection with the construction
or reconstruction of County roads are as follows:
1. County Road Engineer or his representative will:
a. Require road improvement plans, whether for construction by the Department of Public
Works or by a private builder, to show clearly the designated location or relocation of
mailboxes, whether single or in clusters.
39
b. Require with this information any necessary widening or reconfiguration of sidewalks
with suitable knock-outs or open strips for mailbox posts or pedestal.
c. Require these plans to bear a statement on the first sheet that mailbox locations as
shown on these plans have been coordinated with the serving post office at
(City/Community), Washington. This will be a prerequisite to plan approval.
d. Require construction of mailbox locations in accordance with these plans, through usual
inspection and enforcement procedures.
2. Seattle Postmaster or designated serving post office will:
a. Designate location and manner of grouping of mailboxes when so requested by the design
agency. Note on the plans the type of mailbox delivery: NDCBU (Neighborhood Delivery
and Collection Box Unit), or Rural type box. Authenticate by stamp or signature when
these data have been correctly incorporated into the plans.
b. Do all necessary coordination with owners or residents involved to secure agreement as
to mailbox location and to instruct them regarding mailbox installation. Actually
install or relocate NDCBU's if these are the type of box to be used in the neighborhood.
3. Owners or residents served by mailboxes, at time of original installation, will:
a. If using individual mailboxes, clustered or separate, install and thereafter maintain
their own mailboxes as instructed by the post office.
b. If NOCBU delivery, rely on Post Office to provide and maintain NDCBU's.
4. Builders or their contractors shall:
a. Where there are existing mailboxes and no plans to replace them with NDCBU's:
When it becomes necessary to remove or otherwise disturb existing mailboxes within the
limits of any project, install the boxes temporarily in such a position that their
function will not be impaired. After construction work has been completed, reinstall
boxes at original locations or at new approved locations as indicated on the plans or as
directed by the Engineer or Reviewing Agency. Use only existing posts or materials
except that any damage caused by the builder or his contractor is to be repaired at the
expense of the builder.
b. Where there are existing NDCBU's or plans to install NDCBU's:
Call on Seattle Postmaster or designated serving post office to locate or relocate
NDCBU's and make the necessary installation.
40
B. Installation methods are as follows:
I. Mailboxes, in the general case, shall be set in accordance with Drawing No. 5-010 or 5-011.
Boxes shall be clustered together when practical and when reasonably convenient to the houses
served.
2. NDCBU's will be installed by the Postal Service generally in accordance with Drawing No. 5-
012.
5.05 Street Illumination
Continuous illumination will be required for channelization accommodating additional lanes including the
tapers. Illumination will also be required as identifiers where roads intersect arterials or for
frequently used pedestrian areas on arterials.
Widening of arterials with existing continuous illumination will require maintaining the continuous
illumination. Widening to the ultimate roadway width will require illumination designed to current
construction practices.
Illumination intensity and uniformity shall conform with current King County design practices. Luminaire
fixtures shall be consistent with fixtures maintained by the local electrical utility.
5.06 survey Monuments
A. All existing survey monuments which are disturbed, lost, or destroyed during surveying or building
shall be replaced by a land surveyor registered in the State of Washington at the expense of the
responsible builder or developer.
B. Survey monuments shall be placed or replaced in accordance with recognized good practice in land
surveying, and in conformance with Drawings No. 5-014 and 5-015.
5.07 Roadway Barricades
Temporary and permanent barricades shall conform to the standards described in Section 6C-8 of the Manual
on Uniform Traffic Control Devices (MUTCD) and Drawing No. 5-003.
A. Type I or Type II barricades may be used when traffic is maintained through the area being
constructed/reconstructed.
B. Type III barricades may be used when roadways and/or proposed future roadways are closed to traffic.
Type 111 barricades may extend completely across a roadway (as a fence) or from curb to curb. Where
provision must be made for access of equipment and authorized vehicles, the Type Ill barricades may
be provided with movable sections that can be closed when work is not in progress, or with indirect
41
openings that w i 11 discourage public entry. Where job site access is provided through the Type III
barricades, the developer/contractor shall assure proper closure at the end of each working day.
C. In the general case. Type Ill permanent barricades shall be installed to close arterials or other
through streets hazardous to traffic. They shall also be used to close off lanes where tapers are
not sufficiently delineated.
D. Type III barricades shall be used at the end of a local access street terminating abruptly without
cul-de-sac bulb or on temporarily stubbed off streets. Each such barricade shall be used together
with an end-of-road marker.
5.08 Bollards
\1\/ren necessary to deny motor vehicle access to an easement. tract. or trail, except for maintenance or
emergency .vehicles, the point of access shall be closed by. a line of bollards. These shall include one or
more fixed bollards on each side of the traveled way and removable, locking bollards across the traveled
way. Spacing shall provide one bollard on center1ine of trail and other bollards spaced at minimum 50
inches on center on trails 10 feet wide or less. Spacing shall be 60 inches on center on trails wider
than 10 feet Bollard design shall be in accordance with Drawing No. 5-013 or other design acceptable to
the Engineer or Reviewing Agency. No Ii re apparatus access roads shall be blocked in th is manner without
the concurrence of the Fire Marshal. Bollards shall be located at least 10 feet laterally from the paved
edge of roadway.
5.09 Guardrail/Embankment Heights
Guardrail installations shall conform to WSDOT/APWA Standard Plan C-1, Beam Guardrail Type 1 and C-2,
Guardrail Placement. End anchors shall conform to WSDOT/APWA Standard Plan C-6, Beam Guardrail Anchor
Type 1.
Evaluation of embankments for guardrail installations shall be in accordance with Figure 710-6 of the
WDJr Design Manual.
5.10 Off-Street Parking Spaces
The number of off-street parking spaces required shall conform to King County Code Title 21.50. The
specifications for off-street parking spaces shall be as provided in King County Code Title 16.74 and
implementing documeht entitled "King County Specifications for Off-Street Parking, 1982," as updated.
5. 11 Roadside Obstacles
Non-yielding or non-breakaway structures, including rockeries and retaining walls. which may be potential
hazards to the traveling public shall be placed with due regard to safety. 01 roads with a shoulder or
mountable curb, hazardous objects shall be placed as close to the right-of-way I ine as practicable and a
minimum of 10 feet from the edge of the traveled way or auxiliary lane. 01 urban roads with a vertical
curb section, hazardous objects shall be placed as far from the edge of the traveled way or auxiliary lane as
practical, Such an object shall not be placed in a sidewalk or with the object edge nearest the roadway less
than eight and one-half feet from the face of the curb in business areas or five and one-half feet from face of
curb in residential areas. Placement of any uti I ity structures shall be in accordance with requirements of
Chapter 8, to include constraints on placement of poles on the outside of curves.
43
CHAPTER 6. BRIDGES
6.01 Principal References
Except as specified below, King County bridges. whether on public roads or on private roads serving
subdivided land, shall be designed and constructed to meet the minimum requirements set. forth in the
latest edition, including all interim addenda. of "Standard Specifications for Highway Bridges," adopted
by /lASHfO and in accordance with the requirements of WSDOT/APWA Standard Specifications. Bridge and
approach railings shall be provided in accordance with those references or with WSDOT/APWA Standard Plans.
All new bridges shall be designed to carry an /lASHfO H3 20-44 live load or greater. All bridge work shall
comply with K.C.C. 21.54 regarding Special Control Areas and Flood Hazard Areas for stream and wetland
protection and flooding concerns.
6.02 Bridqe Geometrics
A In the general case, the bridge shall comprise the fu 11 width and configuration of the road being
served --traveled way plus curb, sidewalks, walkway, bike lane, equestrian lane and/or shoulder on
one or both sides. Requirements of utilities shall be duly considered. Bridge roadway width shall
be measured between curbs or between faces of rails, whichever is less, but in no case shall be less
than 28 feet
B. \/1/heretypical speed is 35 MPH or higher and significant pedestrian, bike and/or horseback traffic
can be expected. the Engineer may require that the lanes for these other modes of traffic be
separated from motor vehicle traffic by use of a bridge traffic rail and further protected by a rail
at outer edge. On designated bike routes, combination traffic and bicycle railings shall be used.
C Approach railings shall be made structurally continuous with bridge railings and shall meet N>SiTO
specifications as cited in Section 6.01 above.
D. Overhead vertical clearances for motor traffic on the traveled way or under overpasses shall be 16.5
feet minimum. Vertical clearance of structures above a walkway or sidewalk shall be eight feet
minimum and shall be 10 feet on designated equestrian routes.
E. The height of bridge clearance above streams shall be as required by the Surface Water Design
Manual.
6.03 Bridge Desiqn Criteria
A Approach slabs will be required for all bridges and new bridge plans shall provide pavement seats
for approach slabs unless otherwise approved by the Engineer. \/1/aiver or modification of the
requirement for approach slabs w i 11 be considered only on the basis of adequate geotechnical
analysis. Approach slabs shall be constructed in accordance with WSDOT/APWA Standard Plan A-2.
B. New bridge decks and approach slabs shall be designed with a protective system to prevent corrosion
of the reinforcing steel.
C. Criteri~ under c::llier , ecogniz ,t o-oad and bridge project classifications, such as those of 3-R
po-:::jects, set forth i" WSDOT :cal Agency Guidelines, may be applied under conditions deemed
appropri~te by th~ ~ngineer.
D. The design of bridge expansion joints shall consider the presence of bicycle traffic.
6.04 Special Permits
Permit requirements for construction or reconstruction of bridges include but are not limited to the
fo 11 owing:
A. Bridges over navigable waters require U.S. Coast Guard permits.
B. Bridges involving de11ositi:::n c::t 1113tec--13l in waters of the United States or their adjacent wetlands
require a U. S. A~,ny Cc::o-ps :::f ~nginee:"s Permit.
C. Any wo,-.k involving 31t~c--3tion c::f fl:w or bed materials below the ordinary high water line or 3ny
water body o~ water co·,rs: req"· 'r"s a Hydraulic Project approval from the State Department ::of
Fisheo-ies or the St~te De,,artment o;C; Wildlife.
D. Any woc--k within waters :::1' the State o-coquio-~s 3 W3teo-Q"3lity C"c-t iic3tion Waiv.:oo-ro-orn the: St3te
Departm,:,nt of Ecology.
E. Where bridge structures lie on or over submerged l3"ds a le3se: ro-:m th: W3shington State Departmen·
of Natural Resources may be necessary.
F. Structures l:cated c:n shorc,line:· zon~s
development ,ermit ~r:rn the King Coun
subject to c:nc~o-renc: :f the State D
s d:fin:d i• Ling County Code Title 25 require a substantial
Dep3o-tme~t c::r Development and Environmental Services,
3o-tm~nt o~ ~c~logy.
G. Bridges over waterways req·, ire: the Eng ,n=eo-' s a ppr: 1/31 or Ohe size and shape of the hydraulic
opening, the height of the suµ=rstruct~r= ove" hig~ watcr, the location of piers, channel
improvement, and other hydo-aul ,c c=nsider~tio11s.
45
CHAPTER 7. DRAINAGE
7. 01 General
A. Designs: Drainage facilities shall be designed consistent with King County Code 9.04 and the King
County Surface Water Design Manual, latest edition. Structures shall be placed and constructed as
shown in the Standard Drawings.
8. Specifications:
Specifications.
Materials, construction, and testing are specified in the WSDOT/APWA Standard
The Engineer may amend, delete, or add specifications or Standard Drawings.
C. Conflicts: Where technical conflicts ~ay occur between this document and the Surface Water Design
Manual the Engineer shall decide which document governs.
7.02 Road Ditches
The following standards shall only apply in design of drainage ditches not requiring drainage review under
the provisions of the Surface Water Design Manual.
A. On grades up to ru percent, grass lined ditches with grasses as specified in 7.02D shall be used for
the drainage requirement. These ditches shall be designed and constructed in accordance with
Drawings No. 1-001, 1-004 and 1-007. If grass cannot be readily established by usual seeding
method, other methods such as sodding or seeding with slope mat protections shall be used as
necessary. For gradrus between 3 percent ~rnd 6 prurc~nt, grass lining alone may not be sufficient to
stop erosiom. Prruferred methods to furthru, rruduce potential ~rosion problems include the use of
check dams or widrur ditch sections. Rock-~inrud ditchrus shall be avoided whenever possible.
8. Where the grade is over 6 percent and not 8ver 9 percent, the Engineer may direct use of a standard
rock-lined ditch or alternatively a closed (pipe) drainage system under a paved shoulder with
asphalt curb or turnpike shoulder. As an exception, cul-de-sacs with over 6 percent grade shall be
provided with pipe drainage and not with rock-lined ditches.
I. Th~ s~3rndard cock lining shall be in accordance with the S1rf3cm W=;tmr rup,.sign '.3n13l and
Section 9-13 0 of the WSDOT/APWA Standard Specifications. Rock ~r=;dation sha11 bm as follows:
Passing 8-inch square sieve
Passing 3-inch square sieve
Passing 3/4-inch square sieve
100 percent
40 percent max.
10 percent max.
2. Rocks shall be placed so as to form a firm, dense, protective mat consistent with examples in
Drawing No. 2-024 and conforming to the design surface of the ditch. Individual rocks shall
not protrude more than three inches from that surface.
46
C. Where the grade exceeds 9 percent either pipe drainage or a special rock-lined ditch shall be
provided unless otherwise approved by the Engineer. The special rock-lined ditch shall be designed
by a professional engineer, based on soils and hydraulic analyses. Design shall include rock
sizing, together with filter rock gradations and/or filter fabric, and be subject to approval by the
Engineer.
0. Grass seed mixture by we ~ht may Je 10 percent Colonial bentgrass, 40 percemt Tall or Red fescue,
10% White clove~, hydros~md at IZO lbs./acre, handseed at 3 lbs./1,000 square feet. Where there is
high groundwater, th~ fo I lowing species may be substituted er added: Meadow er Pacific foxtail,
Timothy, or Redtop.
7.03 Storm Sewers and Culverts
A. minimum pipe size shall be 12-inch diameter. Eight-inch diameter may be permitted on cross street
Tater3ls less than 66 feet long to avoid utility conflict or meet shallow gradient.
B. Where the time of concentration creating the greatest flow is less than 15 minutes and the system
predominately serves the road, determine flow rates using the rational formula.
C. Driveway culverts shall conform to Drawing No. 3-003.
0. The following pipes, specified in Section 9-05 of the wsru 0 T/APWA Sta~dard Specifications are
allowed: plain and reinforced concrete storm sewer pipe, 3luminized ';'yll)e 2 corrugated steel, steel
spiral rib and corrugated steel with asphalt coating Type I, spiral riJ and corrugated aluminum,
ductile iron, polyvinyl chloride (PVC), lined corrugated roolyethylene ILCPE) and solid w3ll
polyethylene (SWPE) pipe.
E. LCPE pipe shall have a smooth interior wall meeting or exceedin3 Type Ill, Categcry 4 or 5, Grade
P33 or P34, Class C per ASTM D1248, mini~um cell Class ASTM 033co, 324420(. LCP~ shall also meet or
exceed the requirements of AASHTO M294, I ype S. Pipe sha 11 be p-;'aced in accordamce with Ccunty
Specifications.
F. SWPE p ·1:ie with maxi mum SOR of 32. 5, mini mum ce 11 Cl ass ASTM 03350, 334434C and meeting County
Specif'~ations for ductile iron pipe with restrained mechanical joints may be used for cutfalls on
steep slopes.
G. PVC pipe shall require the use of bmdding aterial fer flruxible pipe specified in Section 9-03 of
WSOOT/APWA Standard Specifications.
H. LCPE and SWPE shall be bedded o-gravel backfill for pipe bedding as specified in Section 9-03 of
WSOOT/APWA Standard Sprucifications. Above ground installation of SWPE does not require pipe
bedding.
47
I. PVC, LCPE and SWPE shall be tested using the deflection test procedure describrnd in Section 7-17 .3
of the WSDOT/APWA Standat<d Specifications. Unless otherwise specified the man3rel for the
deflection test shall have a minimum of nine runners equally spaced, a base lmngth equal to or less
than the diameter of the pipe, and a diameter no less than 95 percrunt of the ~asm inside diameter of
the pipe, which is described as follows:
For ruipes with controlled inside diameter, PVC and SWPE: base inside diameter= average inside pipe
diam.J"ter -((inside diameter tolerance)2 + (out of roundness tolerance)2 ) 5 •
For SWPE up to 30-inch the above equation simplifies to: base inside diameter= nominal diameter x
0.9665.
For pipes with controlled outside diameter, LCPE: base inside diameter= (average outside diameter
-(2 x wall thickness)-((outside diameter tolerance)' + (12 percent x wall thickness)'+ (roundness
tolerance)2 )·5 •
Average diameter and tolerances shall be as specified by applicable.ASTM standards. Pipe sections
failing the mandrel test shall be replaced except that reshaping SWPE and LCPE sections to meet
requirements shall be allowed if the original deformation is less than 20 percent.
J. Concrete pipe shall be t<U~ber gasketed and metal pipe shall be gasketed and securely banded. Leak
testing shall bru conduc,nei:: if required by the Engineer.
K. If the depth of a pipe exceeds eight feet or the Engineer questions the pipe selection, then the
selection of pipe material must be made by a professional engineer.
L. Bevel the projecting ends of culverts within the right-of-way.
7.04 Catch Basins and Junctions
A. Catch basins shall be spaced no greater than 150 feet for grades less than one percent, 200 feet for
grades between one and three percent; and 300 feet for grades three percent and greater. Where the
width of the tributary road surface exceeds 35 feet, the cross slope exceeds four percent, or the
IO-year, 24-hour rainfall exceeds three and one-half inches, catch basin spacing analysis is
required, The analysis must show the depth of water at the edge of the traveled way does not exceed
0.12 feet or extend more than five feet into the traveled way for the IO-year storm event, using
flows generated by the rational formula,
B. Use catch basins, rather than inlets, to collect water from road surfaces, unless approved by the
Engineer.
48
C Connect i ans to pi pru sys trums may be rn3dru ',iithout pl 3ci ng a c3tch basin or m3mhc l ru on thru m3 in 1 i n(l) by
mrueting 311 of the followin3 conditions:
I. The mainline pipe is 48 inches or greater and at least two times the size of the connecting
pipe.
2. M3kru connections in accordance with the manufact~r~r' s recomm,rndat ions. Standard shop
fabri c3ted trurus, wyes and saddles shall be used, ruxcrupt fer concrrutru pi pru connect ions
cant.tr~ctrud in accordancru with Drawi n3 No. 2-002
3. There shall be a catch basin or manhole on the connecting pipe within two to ten feet of the
external wall of the main line. See Drawing No. 2-002.
4. Offset angle of connecting pipe to mainline, horizontally and vertically, shall be less than
45 degrees.
D. Connections to 3n existing systrum shall avoid directing project runoff through downstream
quality/quantity control f3cilities. Receiving systems may have separate conveyance facilities:
on(!) connecting to quality/qu3nt ty facilities and one by-passing them. Connection shall be to the
byp3ss system where av3i l abfo.
E. Use Type 2 catch basins where the depth to the invert of the pipe exceeds five feet.
F. Manholes may be used in lieu of catch basins if they do not collect surface water.
G. Roof and yard drains, or other concentrated flow from adjacent property shall not discharge over the
surface of roadways or sidewalks.
H. Catch basins or manholes are required when joining differing types of pipes.
7.05 Frames, Grates, and Covers
A. Unless otherwise specified, use vaned grates with standard frame in the traveled way, gutter, or
shoulder. Vaned grates shall not be located within cross walks,
8. At sag vertical curves, or before i~tersections with a grade 4% or greater, use through curb inlet
frames. Where through curb inlets cannot be used, three vaned inlets shall be used. One shall be
located at the approximate low point and another on either side at 25 foot horizontal spacing, but
not greater than 0.1 foot above thru low point.
C. Use rolled curb frame and (vaned} grates along rolled curbs and in asphalt turnpike shoulders. See
Drawing No. 2-024.
49
D. New catch basins that do not collect runoff shall ~se locking ~anh:le cove~s. See Drawing No. 2·
022. Existing catch basins which no longer callee; runoff sh3;l have thmi~ f~ame and grates
replaced with solid covers (See Drawing No. 2-015).
E. All storm drain covers and grates shall be locking Manufacturer as approved by the Engineer.
F. Slit drains may be used when 3p:~~ved by the Enginee~.
basins at either end 11,l~ss use: ,s a driveway culve~t
along a slit dr3in shail be 50 feet.
7.06 Erosion Control
At a minimum slit drains shall have catch
The maximum distance between catch basins
Provide erosion control as required in the Surface Water Design Manual.
Filter fabric fences shal~ ~e c:nstructed of material designed specifically for erosion control. The
fabric shall be composed:~ rot-:roof (;J()Ven or non-woven polymeric fibers and be free of chemical
treatment or coating that m3y re:uce permeability. The fab~ic shall meet the following test requirements:
minimu,,, 110 lbs grab tensilm strength per ASTM 0-1682, minimum 40 lbs puncture strength per ASTM D-751
Modified, a,,d 20-100 Equiv3lent Opening Size (EDS) based on U.S. standard sieves.
7.07 Trenches. See Smction 8.03.
50
CHAPTER 8. UTILITIES
8.01 Franchising Policy and Permit Procedure
A. Utilities to be located within existing and proposed County road right-of-way shall be constructed
in accordance with current franchise and/or permit procedure and in compliance with these Standards.
In their use of the right-of-way, utilities will be given consideration in concert with the traffic
carrying requirements of the road which are, namely, to provide safe, efficient and convenient
passage for motor vehicles, pedestrians, and other transportation uses. Aesthetics shall be a
consideration. As a matter of policy, undergrounding of electric utilities will be strongly
encouraged, particularly in urban development. Also, utilities are subject to County policies
relating to drainage, erosion/sedimentation control and sensitive areas as set forth in KCC 9.04 and
21.54 and the Surface Water Design Manual.
B. A 11 permits for new pl a cement and rep I a cement of existing ut i 1 ity pol rus and o thrur ut i 1 i ty st r ctures
above grade shall bru accompanirud by written certification from a professional engineer or fro an
agrunt authorized by the utility to certify that the inst3llations conform to these Standards nd
that the proposrud work is in conformity with sound runginrnruring principlrus relating to highway
S3foty.
C Rruqurusts for exclllptions to thmse St3rndards will bill irocrussllld in accord3rnclll with variamcm irocedure
as rrufrurruncrud in Section 1 08.
8.02 Standard Utility Locations Within the Right-of-Way
Utilities within thru right-of-way on new reads or on roads whrure existing topogr3phy, utilities or storm
drains are not in conflict, shall ~e located as shown in typical sections, Drawings No. 1-001 through
1-006, and as indicated brulow. Wherm ruxisting utilities or storm drains are in place, new utilities shall
conform to these Standards as nearly as practicable and yrut bru compatible with the existing installations.
Above ground utXiti(IJs located within intrursections shall bru placed so as tc avoid conflict with placement
of curb ramps.
A. Gas and Water Lines:
1. Shoulder-and-Ditch Section:
If practical: Outside of ditch line.
Otherwise: In shoulder three feet from edge of traveled lane.
2. Curb and Gutter Section:
Prrufrurable: One and one-half feet back of curb, or at distance which will clear root masses
of street trees if these are present or anticipated.
51
Otherwise: Its thru street as
dt<ainage system.
pt<ior to placing
close t 0 the curb as practical without encroaching on the storm
Mains 3nd srurvice connections to all lots shall be completed
of sut<f3cru matrurials.
3. Designated Side of Centerline:
GAS: South and West. WATER: North and East
4. Depth: 36 inches minimum cover from finished grade, ditch bottom or natural ground.
B. Individual water service lines shall:
1. Be placed with minimum 36-inch cover from finished grade, ditch bottom or natural ground.
2. Use road right-of-way only as necessary to make side connections.
3 Fot< 3ny one connwcticn, not wxbnd tsorw th3n 60 8wrut alcng or t0rough thru t<ight-of-way, ct< t~-e
minimum width of the wxisting right-of-way.
4. Water meter boxes, when placed or re-placed, shall bw locate~ on thw right-of-way line
immediately adjacent to the property being served, unless ot~wrwise approved by the Engineer.
Meter box locations within the right-of-way may be ap]rov~d ~y the Emgineer based on site
conditions which make routine service access difficul.0 ot< impr3ctica7.
C. Sanit3ry Sewet<s: In the gwnet<3l casw, fivw hwt south and west of cenbt<linw; dwpth 3~-inch minimum
ccvwr fram finishwd gt<ad~, di9ch ~ottom Ot< natUt<3l grownd.
D. In the case of individual sanitary sewer service lines which are force mains the pipe shall:
1. Be minimum two inches I.D., or as required by the utility to maintain internal scouring
velocity.
2 ~f nonmet3llic, contain wir~ ot< oth~r 3ccw~table ~t<oximity dwt~ction 8~stut<~s; ot< bw ilacwd in
3 cast iron or oth~t< acce'1).na~~w m~t3l c3simg. ·
3. Be placed with minimum three-foot covOlr from finish~d grade, ditch bottom or natural ground,
within 10 degrees of perpendicul3r to t<03d cwntwt<lin~, and extend to right-of-way line.
4. Be jacked or bored under road unless otherwise approved by the Engineer.
E. Sanitary and wahr 1 i 11ws sha 11 bw swp3rahd in accot<damc~ with good wn3 i n~wri ng pt<act cw such as the
Ct<ihria for Sewag~ Work Design, W3shington DwparteJ~nt on Ecol8gy, labst ~dition.
52
F. Gravity systems, whether sanitary or storm drainage, shall have precedence over other systems in
planning and installation except where a non-gravity system has already been installed under
previous approved permit and subject to applicable provisions of such permits or franchises.
G. Electric utilities, power, telephone, cable TV: Preferable: Underground with 36 inch minimum
cover, either side of road, at plan location and depth compatible with.other utilities and storm
drains. Otherwise: Every new placement and every replacement of existing utility poles and other
utility structures above grade shall conform to the following:
1. Utility poles or other obstacles may be placed within the right-of-way and shall be as far
back from the traveled way or auxiliary lane as practicable.
a. On shoulder type roads, poles or obstacles shall be located back of ditches and in
accordance with criteria in Drawing No. 5-001 unless protected by concrete barrier,
suitable impact attenuating device or placed more than three and one-half feet behind
face of guardrail, as allowed by an approved variance.
b. On vertical curb type roads with a speed limit less than 40 miles per hour, poles or
obstacles shall be placed clear of sidewalks and at least eight and one-half feet from
face of curb in business areas and five and one-half feet from curb face in residential
areas. On urban roads with a speed limit of 40 miles per hour or greater, poles and
obstacles shall be placed in accordance with Drawing No. 5-001.
c. Notwithstanding the other provisions regarding pole locations described in these
standards, no pole shall be located so that it poses a hazard to the general public.
Utilities shall place and replace poles with primary consideration given to public
safety.
2. The above constraints on pole and obstacle location will not apply to locations not accessible
by moving vehicles, "breakaway" structures whose break-off resistance does not exceed that of
4" x 4'' wood post or a 1-1/2-inch standard (hollow) iron pipe or to "breakaway" fire hydrants
installed to manufacturer's specifications.
3. Deviations from these pole and obstacle clearance criteria may be allowed by an approved
variance when justified by suitable engineering study considering traffic safety. Only the
Utility may request a variance from pole and obstacle clearance criteria. Up to three
contiguous damaged or weakened poles may be replaced at existing locations under permit in
accordance with emergency procedures, however, sequential permits resulting in continuous
replacement of a pole line shall not be allowed. A pole or other obstacle which incurs
repeated damage from errant vehicles shall be relocated or protected.
4. Locations of poles shall also be compatible with driveways, intersections, and other road
features (i.e., they shall not interfere with sight distances, road signing, traffic signals,
53
culverts, etc.). To the extent possible, utilities shall share facilities so that a minimum
number of poles is needed.
5. Wher~ road uses leave iusufficient ovmrhang, ancr,or, 3nd lrme-trimming space for overheod
utilities, consideration wil I be given to variance fr0 r11 the Standards or to acquisition of
additional easmments and/or right-of-way for this pur~ose. Costs incurred for said
acquisition shall be borne by the develo~er, builder, or othmr ~arty initiating the road
construction. Howmvlllr, the associated c'.lst of relocating thm uOil it.Y shall 11ot be bo-ne by
King County. ·
H. Notwithstanding other provisions, undmrground systems shall bru located at least five feet away from
road centerline and where they w·,11 not othmrwise disturb lllxisting survey monumentation.
8.03 Underground Utility Installation
A. General: The WSDOT/APWA Standard Specifications, particularly Section 7-17.3(3) will generally
apply unless otherwise stated below.
B. Utility Cuts On Existing Traveled Roads
I. In tr!llnchin~ through existing pavrument, the opmn cul shall be a neat-linm cut
saw cutting or jackhammmrin3 a continu::ous line. Trench sides shall be k~pt a
as possible. Compaction anc -estoration must be don!ll as detailed below 3nd i
the trmnch is backfilled, so as to c3use lmast disru:tio~ to traffic. Cement
ruavemrunt shal I be cwt one foot outsicru the edgm of tre t-mnch on each side.
ade by either
nearly vertical
mdiately after
oncrrute
2. In cuts parallel to road alignment:
a. All trench backfill under roadway shall be mechanical l_y com:acted to 95 pmrcent of
maximum density except for trenches over eight femt in druptn. Throughout the length of
any pipe run, manhole to manhole, in which any part is over eight feet dmep, llackf i 11 at
drupths c vrur four T'llJllJt sha 11 be conpacted to 90 percmnt maximum density by ei toer water
settling (sem Subsection 8.03C ~mTow) ~r mechanical cornp3ction. The to11 four feet of
thru trench line shall then be mechanically comp3cte~ to 35 percemt. An dmnsities shall
bru dlllnerminrud by testing specified in Section 2·03.j(l4)o of WSOOT/APWA St3ndard
Specifications.
b. In any trench in which 95 percent dmnsity c3nnct be achieved with existing b3ckr'ill, the
top four feet shall be rruplaced wit, gravml basru as specified in the WSDOT/AruWA Standard
Specifications, Sruction 3-03.10. Tois nmw matrurial shan then be mechanical~y comru3cted
to 95 percent.
C Rrustoration of a trrunch within an asruhalt pavement shall include a minimum o~ six a~d
onm-half inchms of crushed surfacing mah~ial and asruhalt concrrutm Class B tb samru
54
thickness as the existing asphalt pavement or a m1n1mum of two inches, whichever is the
greater. Pavement shall then be overlaid full width with a minimum of one inch
compacted asphalt concrete Class 8. Any exceptions to this overlay requirement will be
on a case-by-case basis, swbject to approval by the Engineer, considering the existing
conditions of the pavement. Concrete pavement shall be restored consistent with Section
6-02 of the WSDOT/APWA Standard Specifications. Any concrete pavement traffic lane
affected by the trenching shall have all affected panels replaced.
3. In cuts transverse to road alignment:
a. In general, utility trenching through exisLing paverna;nt across tne road a-;-ignment will
be discouraged. It will not be permitted unless it can be shown that alt~rnatives such
as boring or jac)ing are not pcssible due to conflicts er scil conditions or wnless the
utility can be installed just prior ta reconstruction or cverlay of the read.
b. Without exception, the entire trench shall be backfilled with crushed surfacing top
course meeting the requirements of Section 9-03.9(3) of the WSDOT/APWA Standard
Specifications. Backfill shall be placed and compacted mechanically in six inch lifts
with a County inspector present. If the capability can be demonstrated, based on
compaction equipment or quality of backfill to achieve 95 percent density in thicker
lifts, the depth of backfill lifts may be increased up to one foot. After backfill and
compaction, an immediate cold mix patch shall be placed and maintained in a manner
acceptable to the Engineer. On asphalt pavement, a permanent hot mix patch the same
thickness as the existing asphalt or a minimum of two inches, whichever is the ~realer,
shall be placed and sealed with a paving grade asphalt within 30 calendar days. Cement
concrete pavement shall be restored with an eight-sack mix, using either Type II er Type
III cement, within 30 calendar days.
C. On Proposed Roads (e.g., New Subdivisions): Backfil I c~mpaction for trenches within the roadway of
roads not open to public travel may be achieved throughout the entire depth of the trench, either by
mechanical compaction as described in B.2 above, or by the following alternative method, namely,
water sett 1 i ng:
I. Prior to electing to use the water settling method of compaction, a review of the site shall
be done to determine suitability of the use of the water method and a compaction pl an
submitted by a professional engineer. Compaction plan is subject to approval by the Land Use
Inspection Section.
2. Where water settling of treniches is done, the jetting method shall be used. In tren bes over
eight feet deep the Eng i nee.-111ay direct the backf i 11 to be placed in Lwo or rrore l if t and
each be jetted separately. Jets sOall b~ inserted at not more than four-foo, interv as
throughout the length of the bac filled 3r~a 3nd shall be slowly forced, on ,he firs tlift,
down to the bottom of -,he trench and helc unl.l the trench backfill is ccrnptetely sa orated
with water.
55
Penelra~ion shall be lo the crown of the pipe, to native ground on sidru slo~es, and
subsequruntly to each p,eceding lit~. The jetting oprurations shall be compl~trud as soon as
practic3blru af.rur the ~ipe laying 3nd as part of the backfilling ope~at\ons.
3. After the water-sruttled trrunch has set for sruveral days and thru backfill is visibly dry, firm
and stabilizrud, any de~ression in the trench shall be fillrud and mounded up over th etrench.
It shall then be furth~~ compacted by the us~ of accept3ble vibratory compac.ion eq upment
providing 95 prurcrunt oo maxi murn density comp3c, ion .
4. The m1n1mum size of hose and equipment
square inch pressure at the discharge.
diameter of one inch.
shall be such as to provide not less than 35 pounds per
The jet shall be rigid iron pipe with a minimum inside
5. Source of water will depend upon local conditions. Hydrants or srurface water sources shall be
utilized when such sources of water exist within 700 feet of tOru operations. Hauled water may
be utilized when the water settling operation is more than 700 nemt. from a hydrant.
D. Controlled Density Backfill:
As an alternative to mechanical compaction, trench backfill above the bedding and below the base
course or ATB may be accomplished by use of controlled density backfill (CDFJ in a design mixtcr,
approved by the Engineer. On crossings required to be opened to traffic prior to final trench
restoration, steel plates may be used as approved by the Engineer.
E. Testing:
1. Consistent with the above and prior to placing any surface materials on the road',;ay, it shall
be the responsibility of the develope~ to provide density test reports certifiilld by a
professional [!)n3ineer. A minimum of ome test shall be taken within every 500 ~et cf t-ench
length and 3t drupths up to 50 percent of trench depth, or as directed by the Engineer
Compaction ;'.f laterals or service 1 inm trenches shall be tested where directed by th•
Engineer. lesting of CDF shall be in aw:ordance with ASTM 04832.
2. Whichmv e comJa tion n~thod
not les sthan 9 Opercent ma
less th a 95 p~ cent maximu
the top forur fee shall be
95 perc ~t as i nB.2 above.
F. Notification and Inspection:
the install[!)r rulructs, the backfill b~low four feet must test to be
mum density and the upper four feet cf backfill must test not
mdensity. Whrur[I) this cannot bill achieved, all affected backfill in
neoved and ~eplacrud by gravel ~ase and mechanically compacted to
1. Consistent with Section 9.02 of these Standards, any developers, utilities, or others
intending to trench in existing or proposed traveled County roads shall notify King County
56
Land Use Inspection or Utility Inspection office not less than one working day prior to doing
the work. This notification shall include:
a. Location of the work
b. Method of compaction to be used
c. Day and hour when compaction is to be done.
d. Day and hour when testing is to be done.
Phones are as follows:
King County Land Use Inspection Section
King County Utility Inspection Section
296-6645 (north) and
296-6646 (south)
296-8122
2. As set forth in Section 9.03 of these Standards. failure to notify may necessitate testing or
retesting by King County at the expense of the Developer or Utility. Furthermore, the work
may be suspended pending satisfactory test results.
8.04 Final Utilitv Adjustment (To Finish Grade)
A. Al I utility covers which are located on proposed asphalt roadways shall be temporarily placed at
subgrade elevation prior to placing crushed surfacing material.
B. Final adjustment of a 11 covers and access entries shall be made following final paving by:
1. Saw-cutting or neat-1ine jackhammering of the pavement around lids and covers. Opening should
. not be larger than 12 inches beyond the radius of the cover.
2. Removing base material, surfacing course, and frame; adding raising bricks; replacing frame
and cover no higher than finished grade of pavement and no lower than one-half inch below the
pavement.
3. Filling and mechanically compacting around the structure and frame with crushed surfacing
material or ATB, or pouring in five inch minimum thickness of cement concrete Class 3000 to
within two inches of the top.
4. Fi 11 in g the remaining two inches with asphalt concrete Class B hot mix. compacted and sealed
to provide a dense. uniform surface.
5. Final adjustment of all covers and access entries shall be completed within 30 days of final
pav1 ng.
57
8.05 Final Cleanup. Restoration of Surface Drainage and Erosion Control
In addition to restoration of the road as described above, the responsible utility shall care for adjacent
areas in compliance with Sections 1-04.11 "Final Cleanup" and 8-01 "Roadside Seeding" in the WSDOT/APWA
Standard Specifications. In particular:
A. Streets and roads shall be cleaned and swept both during and after the installation work.
B. Disturbed soils shall be final graded. seeded and mulched after installation of utility. In limited
areas seeding and mulching by hand, using approved methods, w i 11 be acceptable.
C Ditch lines with erodible soil and subject to rapid flows may require seeding, jute matting,
netting, or rock lining to control erosion.
D. Any silting of downstream drainage facilities, whether ditches or pipe and catch basins, which
results from the utility installation shall be cleaned out and the work site restored to a stable
condition as part of site cleanup.
CHAPTER 9. CONSTRUCTION CONTROL AND INSPECTION
9.01 Basis for Control of the Work
A. Work performed in the construction or improvement of County roads, whether by or for a private
developer, by County forces, or by County contractor, shall be done in accordance with these
Standards and approved plans and specifications (Section 1.07). It is emphasized that no work mav
be started until such plans are approved. Any revision to such plans shall be approved by the
Engineer before being implemented.
B. The Engineer w i 11 have authority to enforce the Standards as well as other referenced or pertinent
specifications. Hew i 11 appoint project engineers, assistants. and inspectors as necessary to
inspect the work and they will exercise such authority as the Engineer may delegate.
C Provisions of Section 1-05 of the WSDOT/APWA Standard Specifications shall apply, with the term
"Engineer" therein construed to be the County Road Engineer as defined in Section 1.10.
9.02 Subdivision. Commercial and Risht-Of-Wav Land Use Insoection
On all road and drainage facility construction, proposed or in progress, which relates to subdivision.
commercial and right-of-way development, control and inspection w i 11 be done by the Land Use Inspection
Section, (LUIS), acting for the County Road Engineer. Unless otherwise instructed by the Engineer,
construction events which require monitoring or inspection by LUIS are identified as follows, with prior
notification to LUIS (telephone 296-6645 (north) and 296-6646 (south))
A. Preconstruction Conference: Three working days prior notice. Conference must precede the beginning
of construction and include contractor. designing engineer, utilities, and other parties affected.
Plan approvals and permits must be in hand prior to the conference.
B. Clearing and Temporary Erosion/Sedimentation Control: One working day notice prior to initial site
work involving drainage and installation of temporary water retention/detention and siltation
control. Such work to be in accordance with Section 7 06 and the approved plans.
C Utility and Storm-Drainage Installation: One working day notice prior to trenching and placing of
storm sewers and underground utilities such as sanitary, water, gas, power, telephone, and TV lines.
See Section 8.03F Notification and Inspection for additional information.
D. Utility and Storm Drainage Backfill and Compaction: One working day notice before backfill and
compaction of storm sewers and underground utilities.
E. Subgrade Completion. One working day notice at stage that underground utilities and roadway grading
are complete, to include placement of gravel base if required. Inspection to include compaction
tests and certifications described in Sections 8.03 and 9.04.
59
F. Curb and Sidewalk Forming: One working day notice to verify proper forming and preparation prior to
pouring concrete.
G. Curb and Sidewalk Placement: One working day notice to check placement of concrete.
H. Crushed Surfacing Placement: One working day notice to check placement and compaction of crushed
surfacing base course and top course.
I_ Paving: Three working days notice in advance of paving with asphalt or portland cement concrete.
J. Structural: Three working days notice prior to each of critical stages such as placing foundation
piling or footings. placement and assembly of major components. and completion of structure and
approaches. Tests and certification requirements will be as directed by the Engineer.
K. Final Construction Inspection: 15 working days prior to overall check of road or drainage project
site, to include completion of paving and associated appurtenances and improvements. cleaning of
drainage system. and a 11 necessary clean-up. Prior to approval of construction work. acceptance for
maintenance and release of construction performance bonds. the developer/contractor shall pay any
required lees. submit any required maintenance and defect financial guarantees, provide a
certificate of monumentation and submit one photo mylar or ink-on-mylar set and sets of blue Ii n e
final. corrected plans (as-built) reflecting all minor and design plan changes of the road and
drainage systems. The Reviewing Agency shall specify the number of blue Ii n e sets as warranted by
the type of improvement. Mylars and blue line drawings shall not have shading or adhesive addition
in any areas. If original plans were completed on a CPU) system. the developer/contractor shall
submit. in addition to mylars, a copy of the CPU) drawing files in OOS/AUTOCAD format.
L. Final Maintenance Inspection: 30 days prior to the end of the maintenance period. Prior to release
of the maintenance guarantee. there shall be successful completion of the maintenance period as
described in Section 1.09, repair of any failed facilities and the payment of any outstanding lees.
9.03 Penalties for Failure to Notify for Land Use Inspection
Timely notification by the developer as noted above is essential for the County to verify through
inspection that the work meets the standard. Failure to notify in time may oblige the County to arrange
appropriate sampling and testing alter-the-fact. with certification. either by a professional engineer or
the King County Materials Engineer. Costs of such testing and certification shall be borne by the
developer. At the time that such action is directed by the Engineer. the Engineer may prohibit or Ii m, t
further work on the development until all directed tests have been completed and corrections made to the
satisfaction of the Engineer. If necessary, the County may take further action as set forth in King
County Code Title 23. Enforcement.
9.04 E11banlanlllnt constrwction Control in Druye]QJments
The provisions of Section 2-03 of the WSDOT/APW[I) Standard Specifications apply in all respects to
development comtt ruction "n less otherwise in st r1c ted by the Engineer. The fo 11 owing el rumen ts a re
mentioned for clarification and emphasis:
A. Embankment and Cut Section Compaction: Compaction of t~e top two feet of fill subgrade and top six
inches of cut subgrade shall meet a minimum 95 percent of maximum density in accordance with
WSDOT/APWA Standard Specifications Section 2-03.3(14)C -Method B. Subgrade fi11 below the top two
feet shall be compacted to 90 percent of maximum density.
B Testing for Density
1. Jrior to placing any swrfacin3 m3trurial on the roadway, it will Je thru resmonsibility of the
Clllveloplllr/contractor to provice censity test reports reviewed anC approved by a professional
engineer. Optimum moisture content and maximum density shall be determined by methods cited
in Section 2-03.3114)0 of WSDOT/APWA Standard Splllcifications or my other test procedures
approvllld by the C0 unty Road Enginelllr. In fill sections, a rninim1i1111 of one test shall be tabn
for every 1,000 cwbic yards or fraction thereof and on each lift of embankment. In cut
sections, the interval shall be illVlllry 100 feet of roadway. For work to be accepted tests must
show consistent uni form density 3S requ i rrud by trusts referlllnced abovlll.
2. In cases where tests do not meet the minimum standard, corrective action shall be taken such
as adding water, aerating, replacing material or applying more compactive effort as directed
by the developer's engineer. Retests shall show passing densities prior to placing the next
lift of subgrade fi 11.
3. For trenching in existing roads, see Section 8.03.
C. Finishing Subgrade
Aftlllr the subgrade preparation has blllen completed, it shall bru thoroughly chruckrud by the
devruloJmr/contractor using 3 lruvel, string line, crown board, or other means to determine that thru
sub3raCe conforms to the ty(l)ical section or< speci3l pl3n conditions prior to placing any s~rfacing
matrori al.
9.05 Traffic Control in Development Construction
A. Interim Traffic Control: The developer/contractor shall be responsible for interim traffic contra
during construction on or along traveled County roads. When road or drainage work is to be
performed on County roads that are open to traffic, the developer/contractor will be required tc
submit a traffic control plan for approval by the Reviewing Agency prior to beginning the work.
Traffic control shall follow the guidelines of Section 1-07.23 of the WSDOT/APWA Standard
Specifications. All barricades, signs and flagging shall conform to the requirements of the MUTCO
61
Manual. For more specific requirements for barricades, see Section 5.07 and Drawing No. 5-003.
Signs must be legible and visible and should be removed at the end of each work day if not
applicable after construction hours.
B. Temporary Road Closures and Detours: Vllre1 temporary road closures cannot be avoided the
developer/contractor shall post "To Be Closed" signs a minimum of five days prior to the closing.
The types and locations of the signs shall be shown on a detour plan. A detour plan must be
prepared and submitted to the Department of Public Works. Traffic and Planning Section at least 10
working days in advance, and approved prior to closing any County road. In addition, the
developer/contractor must notify. in writing. local fire, school. laiv enforcement authorities, Metro
transit, and any other affected persons as directed by the Engineer at least five days prior to
closing.
C Haul Routes: If the construction of a proposed development is determined by the Reviewing Agency to
require special routing of large trucks or heavy construction equipment to prevent impacts to
surrounding roads. residences or businesses, the developer/contractor shall be required to develop
and use an approved haul route.
1/Vhen required, the haul route plan must be prepared and submitted to the Reviewing Agency and
approved prior to beginning or continuing construction. The haul route p Ian shall address routing.
hours of operation, signage and flagging, and daily maintenance.
If the developer/contractor's traffic fails to use the designated haul route, the Reviewing Agency
may prohibit or Ii mi t further work on the development until such time as the requirements of the
haul route are complied with.
D. Haul Road Agreement \/\rhen identified' as a need by the SEPA review process or by the Engineer, a
haul road agreement shall be obtained by the franchised utility, developer or property owner
establishing restoration procedures to be performed upon completion of the haul operation.
9.06 County Forces and Countv Contract Road Insoecti on
Road construction performed by County forces or by contract for the County w i I be inspected under the
supervision of the Engineer.
9.07 Call Before You Dig
Builders are responsible for timely notification of utilities in advance of any construction in right-of-
way or utility easements. The utility One-Call Center phone number 1-800-424-5555 should be prominently
displayed on the work site.
THIS PAGE INTENTIONALLY LEFT BLANK
64
VTUN POU Do_ ·-SliOUI.DER 4 ~
SAH. SEWCFI ON
SOUTH • WEST ODE c,r SlRECT.
SEE S[C. 3.0lC~
OITCH 7
NOTES
G,.l,S LINES ON SOUTH
4' WEST S[E OF ~
SEE Y C a.0-2.1
' CRUSHED SURF"ACING 6,t,SE COURSE
AOtllTIONAl TREATMENT MAY BE
fll"QUJRCO OEP[No.«; ON SOIL
COHMIONS Y E SEC. 4.02 &
4.03
TMIS DRAV\1/\G ILLUSTRATES A :YPIC/\L ASPHALT CONCRETE ROAD SECTION. ALTERNATr\/E ll
WITH GRAVEL SHOULDERS ACTUAL SURFACING JESIGN FOR ARTERIALS AND C:JMMEKCIAL
'
ACCESS S1REETS Sf-llill BE BASED ON SOILS AND TAAfFIC ANALYSIS PER SEC. 4.C3 DESIGN
FOR RESiOENTIAL P1CCESS STREETS SHALL 8[ IN 1\CCORDANCE WITH SECS 4.01 AND 4.02.
2 SHOULDERS SHALL BE SURFACED ;:,s REQUIRED BY SECS 3 ,:,,: /\ND 4.01. IF PAVED
SHOULDER SLOPE SHALL MATCH CRO\/VN SL.OPE lK O U2 FT./f'T.
3. GRADES:
MINIMUM
M.AXO.tUM
o.~~
SEE SECS 2.02 2C3 204 AND 2.11
4 FOR VVIDTHS O;; PAVEMENT. SHOULDER AND RIGHT-DF-WAY S:..L SECS 2 :J2 2.C·3 7 04
S. FOR CLEARANCE OF UTILITY POLES SEE SEC. 8.02G A"JD DN3. NO. 5-Cl01
6 SEE SEC. 3.08 FOR SEPARATED ',VNJ<:111/AY .F REQUIRED.
7. DITCH SECTIONS AND/OR LOCATIONS rv!AY VARY T:) MEET REOUlRE'-4ENTS OF THE SUi--U-ACE
WATER DESIGN MANUAL. FOR RUKA!. NUGH30R:-100D COLLECTCRS SEE CMG N'.J. 2-iJ2-1
FOR TURNPIKE SHO,,ILDER ALTERNATIVE.
8 SEE SEC. 5.02 FO>\ SIDE SL.OPE REQUIREMENTS
~ l(tlQ COlfflY PUIIUC WOR<S
t<IN.G COUNTY. WASHINGTON SHOULDER
65
'™'
TYPE ROADWAY
,o·--~
"'"
I_ WATER L1N£S ON
I r~ ~r Jr 3.o2A
Ulllll'Y POL£.::,
DWG.
NO. 1 --001
4 C[lolENT CONCRtTE
CEMENT CONCRETf CURB 6: GVfTER
set DWG. NO. J-002
GAS UNES ON SOITTH 6: MST SIPE or STM:n. stE stc a.OZA
rAI..K:
-run.
7
=2--l
SAi, Srw£1t 00 SOUTH
& WEST SID£ OF STR[ET
stE src e.nc ~ ,
~~1/Qj_[!fl IJIIOTH '41
",· -~'c:·-c,cr"c___
CRIJSI-ED SURF AON<. lo-I' COURSE\
>l)Oljl¢N.IJ.. 'lf!!ATMENT WAY EE
Fl(OUIR[D (l[P(NDINC Off SOL
OONJf!IOHS SEE SEC 40 2 "51 40J
NOTES
"THIS DRA\1\/1,\JG ILLUSTRATES /\ TYPICAL ASPHC>l T CCNCRETE ::;:Qil.D s=.c-100. AL TERNATM'. II.
ACTl,iAL SURFACING DESIGN Fer! ARTERIALS /\ND COMMERC!A.L. ACCESS STR~S SHAU. BE
BASED ON SO'LS AND TRAFFIC AW.LYSlS PER S::C. ~.03. DESIGN FOR RESIOENTlAL. ACCESS
Sl--l.4c.L BE IN ACCORDA\CE WITH SECS '1.01 AND 4 C 2
2 GR.ACES
fv11NIMUM
f'vtAXifv1UM
C.5~
SEE' SFCS 2 UL. 2.03, 2 u.:. AND 2." 1
3 SIDEVVALKS SHALL G[ 8 "I. \1\/[E :I\ BLSINESS DISTRICTS fa.ND 6.5 rf. 1NfE O{\J ARTFRIALS I NEXT
TO TRAFFIC U\NE. 5 rr WIDE IF NE<T TO PP..RKII\G CR Brt<E LANE, ffi RFHINn ~L,'l'~TIN(-j s-11-;,:: .. :
SEE SFCTION J.028
' 2 ,::,::.. MU 2 04
5
·-6" TO B'-6" J
~Of'~~o
~~Al.I(_: ,._
"iiii
<'.:1 ..... -~-~
I l·-.-r-1-1 I
~,~/ -. ·.• TER UfffS (If.I I NOfrlk • EAST SIPE or ~-'S.[[ SEC.
I 8 02A
~~ =.: (1YP )6
6
I
Fffi WIDTHS OF PAVEMENT, SHCULDER. AND RIGl-r-QF_j/VAY SE:: SFGS 7 U)
FCR CLEt.R.£l.J'JCE O-= UTILITY POLES SEE SFC 6.02G MD DAG f\b_ 5-,)0'
SEE CHAPTER 7 FOR: C/\TCI I BA.SIN AND S10RM SEWER LOCATIONS.
SEE SEC. 5 02 FCR SID£ SLOPF F~FQJIREt1.IE~HS DATt I -J.,J.,...J
~ ~ COl.ffTY f'Ul.JC WOA(S
klNG COUNTY, WASHINGTON VERTICAL
66
CURB TYPE ROADWAY imi0 • 1-002
II
= ""·
.02fT./n. ,Yb·
~· CEMENT CONC1Wt $.CEWA.I.K" {TIP)
r
.~
1'1'1.'l'EMI WIDTH
SA.'-! ~ ON SOUTH
,t WfST SIDE OF SlR!:tl.
SEE S£C. S 02C ~
...... ~·~·-~,;--jl
ROW:D CURB. SEE l>ilG. ND. 3-002 --1 I f // // // SlJ&C,ftl,0£ SLOPE 0.02 n./FT.
O..S UNES DN SOUlH • WCST SIDE ___/ IJ /~/ OF STR£[T_ SU: SEC. 8..0iA .-j1'-~~
:t' COMP<CTED O[P<H CLASS 9 1~ _// /
ASPHALT CONCRETE ~ /
,. M~. COMPACTED DEPTH I .
ASPlw.T "TREATED B,'SC
AODIIIONAI. 'TREATMENT W,l,,'f EE
R!:0UIR£D DEPENDING ON SOtL
CONP'TIOHS SEE SEC 4.02
NOTES
1. THIS DRAVVING ILLUSTH.ATES A TYPICAL ASPHALT CONCRETE RO.AD SEC~ION ALTERNATM L
FOR OTHER ALTERNATIVES ANJ POSSIBLE REQUIREMENTS FOR FRACTU~::o JI.GGREGA.-E OR
INCREASED THICKNESS OF SURFACING MATERIALS SEE SECS 4 01 AND 4.02
2 GRADES
MINIMJM
MAXIMUM
0.5~
SEE SECS 2 03 AND 2.1 1
J. SEE CHAPTER 7 FOR CATCH BASIN A.\10 STORM SEVV1::R LOCATIONS SEE DWG
NO.S 2-019, 2-020, AND 2-021 FOR GRATE DETAILS
4. FOR WIDTHS OF P/IV!::MENT ANO RIGHT-OF-'NAY SEE SECS 2 03
5.
6.
~
FOR CLEARANCE OF UTillTY POLES SE:: SEC. 8.02G AND 0\/VG. NO 5-001.
SEE SEC. 5.02 FOR SIDE" SLOP[ REQLJ·REMENIS
Ki-iQ ~ Ti Fi iii ,: wun{S
KING COUNTY. WASHINGTON ROLLED
DATE
CURB TYPE
IN II
'r·,-·-
N
·-~:-er ,,,. "~
'N~,.Jl,
1 Oh£
il~ --1 I ~, ~ I -~~ ( \ 6 WATER LI.N ES oo ~Ot
,j~....r.,, I HOOTH ,i ~ SlC ,-..;r Of" ROAO
t e.ov.
REVlSIOH
ROADWAY
CA1C1-I ~N &
$10RU ......
{TYP.)
--_l __ l
I _§'!'_J"AP'"PWD°
II
I
II
l'
NU. .1
Ufl.lf't POL( 3_ ·-.!.·-
'"''""'" 'SAM SO!'ER OH SOUTH
& W[ST sa: Of' ~ET
SU SEC. 8.07
NOftS:
G,l,S. l.N:S ON sount
A: Wl::ST 00E OF ROloC)
SEE SEC. l!!l.02A
1 1/T C0MP,IC1'[0 D£P1H CRI..ISM[O
St.lFIFACINC TOP COURSt INCtUOIHG .........
2 1/t' MN. COWP,1,CTEO CR1JSH£C>
$URfAC:N:.'.i: BASE CO\lftSC
ADOff10NAl 11lV.lWENf ~'r' BE
RfOURD D£P00HG ON SOIL
COfOTI(INS. SEE sec. 4.01 ,i: •m
1. GRAVEL SURFACING IS ACCEPTABLE ONLY ON RURAL MINOR ACCESS STREETS
(RESIDENTIAL) MUCH AR£ PRN'ATE STR:EETS. stE SECS. 2.0~ & 2.17,
2. GRADES:
MINIMUM 0.~%
MAXIMUM Si:E SECS. 2.0J & 2.11.
3. F'OR CLEARANCE OF UTILITY POLES SEE SEC. 8.02G & DWG. NO. 5-001.
4. DITCH SECTIONS ANO/OR LOCATIONS I.IAY VARY 10 MEET REQUIREMENTS OF
SURFACE WATER DESIGN UANUAL.
5. SEE SEC. ~.02 FOR SIDE SLOPE R[QVIREU[NTS.
~·-a"
0'-(1'
OAT[
(i) QO COUNTY P\JII..JC WOll(S
KING COUNTY, WASHINGTON GRAVEL SURFACE
68
4·.(J"
SHOIAOUI'"
-J'-(f
_I.It=.[, 3
""·
' ..__ 'N.\TUt Wl[S ON
""""""
~ &-tAsT SI)( or IIIOAO. sa: sr.c
8.02A
IY~
ROADWAY
IJl!LITY POI..[ J
DWG. 1-004
NO.
I' PAV(MfNT WID!H 3
C;.I.S LJNES ON SOI/hi &.: W£St S10[
Of S'IRECt Sl:E stC S OU
NOTES
? COlolPAC'TED DEPTI-1 CU.SS B
ASPl1o'L l CO!iCA rt(
4• Ir.IN COWPAC'rE:D DEPTtt
ASPf.W. T TREATED W E
A[l0(11QW,L TR£Allol[NT W.l' BE
R!'.OUIRED DEPENDING 00 SOIL
COHDrrJOHS SC( SEC 4 02
SA."I. S£M:R ON SOUTH
& WEST SIDE OF STAf.£1_
SEE SEC BOX~
.f-0"
1. THI$ DRA'MNG ILLUSTRATES A TYPICAL ASP~•ALT CONCRETE ROAD SECTICN. ALTER~,.c..-rv·, I.
FOR OTHER AL TERNATMS AND POSSIBLE R~QU:REMENTS FCR FRACTURED AGGREG.4"'.'E OR
INCREASED THICKNESS OF SURFACING MATE'.RlALS, SEE SECS 4 C1 A:-..JD L 02
2 GRADES
MI.\JIMUM
MAXLMl...!M
0.5%
SEE SECS 2 03 AND 2 11
3. FOR \NIDTHS OF PAVEMENT AND ,;IGHT-OF-\IVAY. SEE SECS. 2.03
4 FOR CLEARANCE OF UTILITY POLES SEE SEC 8.02G ANC CV.C \JO 5-G:J1
5 S!::E CHAPTER 7 FOR CATCH BASINS AND STORM SE'J\IER _ocA-:-1or-..s
6. \/1/fau<:.VVAY SHAU. BE CEMEJ\ T CONCRETE. AL TERNA TM rv. OR c=usHED $1_,RFACiNG
ALTERNATM V. AS REQUIRED BY Rtvl€WING 1-\GENCY SEE SEC. 40i.
7 FOR RURAL NEIGHBORHOOD COLLECTORS. SEE ',J,NG. NO 2-02L FOR TURNPIKE
SHOULDER AtTERNATNE
8 SEE SEC 5 0 2 FOR SIDE SLOPE REOUIREME!\ TS
~ l<Nl COlfflY Pl8..IC WORKS
KING COUNTY W..SHINGTON THICKENED
69
3"-0""
EDGE ROADWAY
10·-a" 4
~
5'-0'" I'
1,/TlllT'!' POLE ..
OWG.
NO. 1-005
t-01ES:
r }'_~~
......... ,
-CA$ UHIS ON SOt.nH a Wl'.ST SIDiE
0, STRttT. SEr SEC 8.02A
"r COll"ACTtD D[PTH CUSS 8 ,.._, "'""""'
<' YN. eotrACT[D Dr.Pnt
ASPtW.T TRrAttD MSE
HlUllONAI. TR[ATWCHT WA.Y at
REQWtlO DtPENOINC OH COi.
CONDmONS stt SE.C. 4.02
SAN. stwm ON SOVfM a 'tllCST SU Of S1RtE1.
ut stc. a.me. ~
'
PA~ Mtn'H4
~·-r[_
I. THIS DRAWING ILLU3TRA ES A TYPICAL ASPHAl T CONCRETE ROAD SECTION. AL.TERW.llVE I.
FOR OTI-lER ALTERNATIVES MD POSSIBLE REQUIREMENTS FOR F"RACTUREO AGGRl..GAIE 0:.:
INCREASED T--!ICKNESS or SURFACING MATERW.S. SEE SECS. 4.01 MD :..n2
2 FOR EXTRUDED CURB DETAIL SEE DWG. N:J .3-002.
3 GIW>ES,
MtNIMUU
MAXlMUI.I
0.5'1
SEE SECS 2.03 AND .2,.:n
4. FOH: WIDTHS OF PAVEMENT AND RIG-fT-OF...J,VAY. SEE SECS. 2 W
5 FOO CLEAAANCE 0::: 'JTUTY POLES S± SEC. 8.02G AND ~::.. N:J. S-C{11
6 SEE CHAPTER 7 FOR CATCH BASH AND S'IORM DRAIN LOCATIONS.
7. VVAU0NAY SH),,;,J_ BE CRJSHED SURFACING. Al..~i.?'i..(fi'V'c: Y, CR A.S R::ou1::.:rn
BY REVIEWING AGE\ICY
8 SE SEC 5.02 FOR SID£ SlCf'E REQUIREMENTS.
.. ,. -
KN0 OOlMlY l'UILIC WOfl(S
KING COUNTY, WASHINGTON EXTRUDED CURB ROADWAY
70
10·--
:,.·-·· ,.
_...,,
I
I-wATtA LINES OM
NCRfH. ~ s« or ROitiO. sa stc: . . ,,,.
CATCH~•
~ ......
n I AmrD I
"1UJTY POL[ •
m· 1-006
GVND~ <" RfQUM()) µJ'
O<MO .
(tr R[QtJIR[O)
~· t.tlN.
40' IAIN
xt.ii!!!l =:J o o:i'"n""/n
•.• ,.. I
THICKENED EDGE
50' t,ON.
4Q' t.llN
o.o2fJ.in.
VERTICAL CURB & GUTTER
~
&,HD~ (,r R[QVfl[O) d J
40' MIN.,_
~
'
ROLLcD CURB
(i) KtlG COlfflY l'IJll.JC WOflC8
KING COUNTY, V\IASHINGTON
1
1
1-------------'&00' MAX.~----------~~
I ! ! :
I -ll ~~-I
R/W UN£ ~ &MP
1
·. -==i I ~ = _-: :_ __ -=--__ _,,/--r ~~~-. , ,,, REa,,,,,,
= ~ ~1tz=--·7--,,;_'·'".,, ---~ I I L _ _ .,:'· .,:'· ,I, --
I ·r ' <.
I r----~~ 1 -'*''/
I , ; ~r/
' I •
I I !
71
I
I
NOTES
SEE SEC. 2.08
2 EXTRUDED CURB IS A:_SQ ACCEPTABLE FCR aJTER ECGE AS AL TERNATM
lU S1-i0ULDER AND DITCH SEE ·OWG. NO. 1-DC6
3 ISLAND AT CENTE:;: OF BL'LB SHALL HAM VERTICAL CURB
SEE D.\G NO 3-002_
4. ISLAND IS MANJATORY ',',HEN ~IUS CF PAV'i:D P-REA EXCEEDS 40'
5. ~~E SEC 2 08 FOR CUL-DE-SAC LENGTH EXCEPTION
6. SEE SECS. 2 U3 L 08 AND L 09 Fffi RIGHT-(F'-VVAY REDUCTION
REQUIREMENTS
CUL-DE-SACS DWG. 1-007
NO.
(i)
TEU?ORARl' EASO€NT I
RIGHT-Of-WAY UNE ~
-----------
ASPH,lr,L T R.A.Mf>
. """'-"
i END R0U£D CIJR8-
"°""""
!"' --
V'~·~
~1~
Tr'Pf It 6AARICAO[
L . Vi1rR£S: SHQRTBT I POSS8....t OISTAHCt
I
-~~~=~-------,L--,-1 ASf'W,I..T RANI>
NOTES:
1. SEE SEC. 2.08.
2. BAAR I CADE REQUIRED AT END OF BULB.
SEE SEC. 5.07.
KtlO CCUffY Pla..lC WOA(S
KlNG COUNTY. WASHlNGlON
~ EASl'.WEH\' I
DATE ~ "' ,.,,...._
TEMPORARY CUL-DE-SAC 'Wi~· 1-008
72
Ci)
CUR8 LINE:
NOTES:
1. SEE SEC. 2.08F.
/
~ ·-~_,-R~T-Of-WA< L'NE
------'
,+,
,:,:,.t.
ROUND CORNFRS _/
(R • 2' MtH.)
~,-~
IS~O 2 ,ii ~·
~~-
~ EXTENDED EOCE OF
TRA\'tLED WAY
2. ISLAND REQUIRED ON EYEBROWS WITH R GREATER THAN 25 FEET.
3. MIN. ISL.AND DIAM. SHALL BE 10 FEET
KNCl COUNTY PUBLIC WORKS
KING COUNTY, WASHINGTON
73
E _ ... REVlS!OM
EYEBROW
BY I APPR'D
DWG. 1-009
NO.
(I)
i
~i
II
I
i
i
I
I
i
!i
II
vARln
ST""'-Oo\RO l,IA,T[RL\LS SEC 4 01
VAf!l[S
30' WN
_2_0'MIN ;
" • !; I
Y!:R'f!CJ.L ~ ROUto ~ ~
002 n-1~
S10£WAU< 2 t
IRBA\
so· wN
~1 _io· ~~~
;1
ii
!
I # ctNhh&Zkhh>hW)J);J ««.ZU'{(rt:«K««uyfl'ru,ou,"KM,e:1'.e«ll+::e.zr«rz>itt "i-.":-
w·@
STNtCWID W.T[RW.S SEC. '4.01
NOTE:
1. SEE SEC. 2.07.
2. SEE SEC. J.02.
3. EDGE OF PAVEMENT TO BE CONSTRl.JCTB) AS SHOWN
FOR CUT OR FILL SECTION AS APPRCPRIATE
l<tlO COUNTY 1'18.JC WOll(8
KING COUNTY. WASHINGTON
RI RAL
HALF-STREET
74
emf.· 1-010
~
NOTE:
SE£ SEC. 2,09
··-~ i
i 81 ~j ill ,·-er
II i,
i :1 :.~ I a• '
i i :~
.. ,~--
T COMPACTED DEPTH Cl.ASS 8 ----~
ASPH.lll CO~RE1E
I 1/r' WIN. CO ... u:TEO ()(PlH CAUSHEO ----~
SURFACING lOP COORS£
2 1/2" W~. COWPACTtD OEPTH CRUSH(O ------'
SURf'ACING BA.St COURS[
ADOITIONAL 7RU.TWCNJ MAY 8[ -------~
H(QUIR(O O[Pf:t,,1.im<, Cf.I SOIL
COfft)ff()NS. SEE" SEC. 4.02
20'-0"
""·
!!'-ct
IIAT£
KNl OOlNTY PUIIUC WORKS
KlNG COUNTY, WASHINGTON ALLEY PAVEMENT
75
r-1·-cr
i !! i~ :, II ~1 i
~: i I ~;s»;,s:,.x;:x.;;.¥
RiVISION sr j .,,.R·o I
DETAIL DWG.
NO. 1 -011
TONGU[ END ON INLET ENO
/ CRiXM END ON ounET END
ENDS TO FIi AOJ.I.CENT
P'P( SECTfONS
,___ _________ J~ ~ ~---~OOND =cs :,;r-,-~ END SECTION
I~--------
! ' MIN. IJE'TAL
~· i,jlN PLASTIC -1
---~-~ . -' ~· El.81'! PIPE JOINT~ (TYP.}
\ ::]i
~
PA'rME"Nf & Pl>.NNEO CULVERT LENGTH I
END SECTION
1' WIIN
METAL & PLASTIC PIPE
I
i--------1,-----~~-J --------i ----------,~, -j,
PA'r"M=NT & PUNNED CULVERT L.ENGn, I
NOTE·
SIDE SLOPE SHAU. BE WARPED TO MATCH THE BEVELED PIPE
El fYAIIPN END. V'i'HEN CULVERT IS ON SKEW. BM LED END SHALL BE
ROTATED TO CONFORM TO SLOPE IF SLOPE DIFFERS FROM
3:1, PIPE SHAU BE BM LED ID Mti.TCH SLOPE.
CONCRETE PIPE
I om I REVl'SIOH I ., I ...... I
(®) 1(1,jQ COUNTY f'UBI.JC WORKS BEVELED END PIPE SECTION rmic.
KING COUNTY. WASHINGTON 2-001
76
========
""""' OflM..ETP~
Ci)
rrPE 1, t-L. OR 2
CB .J.$ R!:®11:EO ~OR
PIP£ SllE
NOTES
u ....
(j'"""
1. •o·, ThE INSIDE DW,t OF THE INLET PIPE. SHAL_
2
3.
'
BE 24" ffi LESS. FOR LARGER VALJES OF ""D•.
USE AJ',.f APPROVED STRUCTIJRE
IN NO CASE SHALL TH::. OLJTSDE OIAM. OF THE
INLET PIPE EXCEED ONF-HALF THE INSIDE DIAM.
CF THE MAIN STOPJV SE\lv'ER
'+ OF INLET P. IPE SHALL BE ON 1{1\l)ILJS OF MAIN
STCRJ\.1 DH.A!!\
THE MIN. OPENIN(~ INTO THE EXISTiNG smqM
DRAIN SHALL BE THE OUTSIDE D M OF TI i[
INLET PIPE PLUS 1 IN
5. IF 4 IS GREATER THAN 45' FIELD TAPPING
IS NJT ALLOvVED
6 SEE S:::C. 7 _ 04
7 SEE SEC 7 03 Fm ALLO\/vED IN_ET PIPE t,1 PE.
8. MAINLINE SHALL Hl!v1 4 6 MIN. D .\1 .
KtlQ COUNTY PUBLIC WOP.KS
KING COUNTY. WASHINGTON
n-1 00 P"SI FLOWA8U
CONCRCT[ EIAoelmLL Ml:it:
UND.ISJURB(() U,RTM
BURN CR ClfT INlD PIPE TO
•Jl'!f'lili~ -'1,, \lllll~"s,
MINYQRC£0 COHCAtTE l!ilrT PIPE
QA-E
PIPE
"""'""
REVISION
FIELD-TAPPING OF CONCRETE
tiNOISTIJR8ED E,t,RTH
SECTION B B
SECTION A A
BY I APPR'D I
PIPE ~-2-002
1 13 !!AR HOOP ___.,,-
ff
2 IJ BAA" HOOPS~
)
-~"<' ;>~·~ . r:::>~:::~ > ·""< al I C> ~
fl B,l,11: tM:;H: CORt,Ut ~
IJ BAR tACH SIDE ~
rFWJr ANO GMT[ sa: src. 7.os N¢>
~L.JCA8L£ DWGS.
~ Rls.tR: SECttoN
1 t" RIS[R StCTIOtl
PRCCAS! B,I.S£ SiCTION
(MUSJRDltNT AT Tl-E TOP
()r "TH[
~ IJ BAR [.lrCH WAY
(i) l(f,IQ OOUNTY PUBUC WOPl(S
KING COUNTY, WASHINGTON CATCH
78
DATt
BASIN
NOTES:
1. CATCI--· 3AS1NS SH/\1 I HI· CONSTRUCED IN ACCORDANCE VvITH A.STI\'l
C41S, (AASHTO M 1 !:19) & C890 UNLESS UTI-ERVV1SE SH:)/\,N 0\1
PLANS OR NOTED IN TH[ WSDOT/APWA $TAN0AAO SPECJF"ICATJONS
2 1B M ACCEPTABLE ALTERNATIVE 10 RE8AR. V-.H.DED WIRE
f-'ABH.IC I lA\/ING A MIN. AAEA Ck O 12 SOUARF 1~;C-JES
PEii. R.XJT 1,¥W BE JSEO. ',\£1.DEO \~.IRE FABRIC SH,'\1 ... L
COMFlY 10 ASTiv1 .t..497 (AASHlO M 221:, WIRE FA3RIC
SHALL NJT BE PLACE'O IN KNCX.n.:urs
3. ALL =EINFo;:;:crn CAST-IN-Pl.AC£ CONCRETE SHALL BE
Cl.ASS 4000
4 f-'HLCAST GASES SHA_L BE FLRN.SHED WTiH ClrTOlJIS c.R
KNOCKOUTS KNOCKOJTS SHAU H /1 M A WAf THICKNESS
Of ~ Ll!N ALL P/Pt Sl-lALL BE INSTALLED IN F,'\ClORY
PROVIDED KNOCKOUTS LJNUSt:.D KNOCKQIJTS NEED NJT
BE G~OUICD IF WAU... IS LEFT .t'JTACT
5 KNOCKOUT CR CLTCXJf HOit SIZE IS EQUAL TO PIPE OJTER
OIAM. PLUS O\TCH [tb.S:jN WAU... Tr"ICKNCS...S
0. ROUND ,<NOCKOUIS Ml'.,,Y BE ON All 4 ;-;11Jf:S Vl!IT'l V:A.'<
DIAM. ff 2rf. KNOCKOUTS l\'IA.v :lE EITHER ROUNC CR ""o" SH/\f-'t
7 TI-E MAX O.':r'TH FROM lHI-. 1·1NIS1ICD C-RADE 1C THE
l-'11-'f-INVERT IS 5'-Cf'
S. THE TAPER ClN !HE SIJ[S OF 11 IE PRECAST Bl1SE SECTlrn..J
AND ~ISFH StCJIUN SHALL NO~ EXCEED 1/7' /FT.
G CATCH BASIN FRAfv1F l'J\Jll ('1.//\lL SI IALL BE N ./\CCOR.C·ANCE
Wli'H STMD.AF.D SPECIFICATIO\IS 0,D MEO IHL S1"::;ENG11·1
REQUIRBv1EITTS CF FEDERAl. srt=,]1---10\TION RR-r-6210.
MAnNG SLRFACES SH.£.J....L BE F \IISHED ID ,"l-''>SL,1--ll
NON ROCKING ;:-11 WrlH Af\ Y covrn ;:,OSITl::)N
10 tRPJ\1[ AND CRATE MAY 8[ INSTN...LED WITH Fl Af.G CON'..J
CR CASl INTO l~IS[~
11 FCR C'A";C;H H!1S \JS IN pr~;:::KINS LOTS REFER TO WSDOT/APWA.
S"TMDARD I.J/1G 61 b
12 EDGE OF RISER OR BRICK Sl--1\l l ~H El[ M:JRE TH.AN 7 FR0\1
vtRllCAl.. E[X3[ CF CATC•i BASIN 'vVAU...
"""""" j.,/.,.. .• J
TYPE 1 qm;. 2-003
1 #J8'1.RHOOPFORl;j' ~
:? #3 BAR HOOP FOR 1-r'~ "'-..._
~
/~I
2 13 BAA ttOOf' ______,,,::;.., ----..........EY
fJ BAA EACH CORNER --------
fJ BAR EACH SIOE
~ KING COUNTY PUBLIC WOA<S
KING COUNTY, WASHINGTON
f.j' OR 12'" -,
FRAIAE AND GMTE
SEE SEC. 7.05 AND
APPLICAflLE DWGS
RISER SECTION
ff REDUCING SECTION
PRECAST SASE SECTION
iMEASURE'liENT AT THE TOP
OF THE BASE)
~~ fJ !WI EACH W~'I DATE
CATCH BASIN
79
NOTES:
1. CATCH BASINS SHALL BE CONSTRUCTED lN ACCORDANCE WffH ASTM
C478 {AASHTO M 199) & C890 UNLESS OTHERWISE SHOWN ON
PL.ANS OR NOTED IN THE WSOOT/APWA STAND.ARD SPECJFICATIONS
2. AS AN ACCEPTABLE ALT£RNATIV£ TO REBAR, WELDED WIRE
FABRIC HAV!NG A M!N. AREA OF 0. 12 SQUARE INCHES
PER FOOT MAY BE USED. WELDED WIRE F"A8RI:: SHA.LL COMPLY
TO ASm A497 (AASHTO M 221). WIRE FABRIC SHALL NOT BE
PLACED IN KNOCKOUTS.
3. ALL REINFORCED CAST-IN-PLACE CONCRETE SHALL BE
CLASS ,moo.
4. PRECAST BASES SHALL BE FURNISHED WITH CUTOUTS OR
KNOCKOUTS KNOCKOUTS SHALL HAVE A WALL THICKNESS
OF Z: MIN. ALL PIP( SHALL BE INSTALLED IN FACTORY
PROVIDED KNOCKOUTS. UNUSED KNOCKOUTS NEED NOT
BE GROUTED IF WM.L IS LEFT INTACT.
5. KNOCKOUT OR CUTOUT HOLE SIZE IS EQUAL TD PIPE OUTER
DIAM. PLUS CATCH BASIN WALL TH_ICKNESS
6. KNOCKOUTS MAY BE ON ALL 4 SIDES WITH MAX DIAM. OF 2fi'.
KNOCKOUTS MAY BE EITHER ROUND OR "rf SHAPE.
7. THE TAPER ON THE SIDES OF TI-IE PRECAST BASE SECTION
AND R1SER SECTION SHALL NOT EXCEED 1 /r /FT.
8. CATCH BASIN FRAME AND CRATE SHALL BE IN ACCORDANCE
WITH STANDARD SPECIFICATIONS ANO MEET THE STRENGTH
REQUIREMENTS OF FEDERAL SPECIFICATION RR-F-621D
MATING SURFACES SHALL BE FINISHED TO ASSURE
NON-ROCKING f"IT WITH ANY COVER POSITION.
9. FRAME ANO GRATE MAY BE INSTALLED WITH FLANGE DOWN
OR CAST INTO RISER
10. MAX. DEPTH FROM FINISHED GRADE TO PlPE INVERT SHALL
BE s·-o"
11 EDGE OF REDUCING SECTION OR BRICK SHALL NOT 8£ I-JORE
THAN 2" FROt.l VERTICAL EDGE OF CATCH BASIN WALL.
I . i REVISION f----W-T AP~~·b ~
TYPE 1-L DWG. 2-004
NO.
~
-,.,.;.; '.
TOP ""8 iii f 'l "'-~~·._: -.,'\JJP
j~~i -·:·\··~:.~::-.~<ti ""_,. ·~ I
' h
fftlJ.I[ a: GRATE CR
COVER SEE SEC. 7 05.
AO..IUSTMENT SECTION
(lEVELINO BRO:S OF1 GR.I.C){
RINGS QPTIQN.Al)
STEPS2°0R UDDER. ~l[r,T
WITH N..£T SO SttPS WILL
• ,.. CtEM Plf"t.S. SEE OWG
.·-4(f,'$4-.W',1X'.OO. ~ HO. 2-D06. '
' • .. '. .
• ,_ •; 1
... ,;, ,--,
' ' "' ' ' " ' ' Gl I l
"' ' ' . I I l , ..,
' ' • • '
I .... -·-.. ,· b . ~ [)IAM.-8" .
I l60" DIAM.-" N I 7'Z" DU.M.-ti' ...
.,, ~ OW,1.-17 . •
•'
. :-
L____ ..... I
' • ' • ' ~;1~
PR!.CAST BASE .t
NTtGAAL RIS[R. ... ·--/·.:;: I ~· . . l'-a' FOR 48'. ~·. 6: &rt ow.. '£1 ::, .... ·/;·,: , ._;," 2'-tf FOR 7~ k '.16'" DUi
WN.
SEPNW( C,,Sl N PLACl
•rOR SEPARATE BAS£. Off SEPARATt CfU,,1:L 8,1,CKtll Fffi FOUl'([MTIOHS
CAST-N-PUCE PRECAST BAS£. 6 YN. COMPAC'Tto DEPTl,
ONLY FOO PR[C,AST &\SC ONLY
.I\IOTFS
2
3
•
b
G
7 .
8.
9.
• J
CATC'.,H 3ASINS Sl--{t:iJ...L BE CONSTRUCTED IN ACCOHDA.NC:: WITM ASTt.l
C478 (AASHTO t.1199) AND AS1\1 C890 Ut\'LESS {J"l lER\~11SE SH:J..~/\J UN
Pl ANS ffi i'.OTED IN 1l-E WSOOT/A.PWA. STANDPV--ill SPECIFICATIONS
1-{ANDHOLDS IN A.)JLJSTI-Af:}J:" St::CTIO/\ SH Al L HA M S' MIN CLEARANCE:
STEPS IN U\ICH BASIN SH1\LL KA"v·E f,' \11N C ... EFRA!\CE SEE D1\G
NO 2-006, CATCH BAS!N DETAllS. HANDHOLDS SHALi. BE PLACED
I.\! Al TER/\'.I\Tli\G GRALE RINGS CR LEVELING RRICK C'.JURSE ','.1TH A
II/IN. Cf" ONF: HANDHOLD BE·:vv:"F!\J THL.. LAST STEP A\JO !OP Cf n.JE
1"1/\\JIICU
.ALL RE:INFORCED CAST -IN-PLt..CE CONCnETE :ii-All BE CLASS 4000
.t:iJ...L ~CAST CONCRETE SH1\Li.. GE C W S 4000.
1-'RED;ST BASES SHA.LL B:: FlJR'~IS--E(_j ',\Hd CUTOLJS m
KNOCKOUTS. KNOCKOUTS SHALL ~Ii.VE WALL TH 1CKNESS Cf 2"
i',11N U.\JUSED KNOCKOUTS NEED i\·:JT BE GROUTED II
\.'\/.~ IS Ltn 1w . .;c-P f">ES SHALL BE INSTf,LLED ONLY 1N
FACT CRY K\J.XKOUTS UNLESS OTH=.~1W3E APPROV£D BY n IE
ENGIN::E::;-:
KNOCKOUT CR CUTOL, T I-ICU: SIZE SHAL ... ECL'A.. PIPE ::tm=R
DIA.M, f-'LUS D;TCH BASIN '.'111'.U.. THICKN::.ss 1,1.AX, HOLE
SIZE SHALL RE ,F: FOR 48" CATCH GASIN. 42" FCR 5 ~" C ~.,
-48" fCR 6 4 CB 6 4 Fffi 7 1 CB 84~ fCR 9 6 CB. fvH">J
DISTANCE BEflVEEN H:JLES SHALL BE fi' roo 46". 54•, /\J\10 6o"'
C8 1t" FOR 7Z" AND 96"" C.B
CATCl-1 BASIN "'~JIES ANC ·2RAll:S CR CO/v1RS SHALL BE I N
ACCORDANCE WITH SEC. 7.0~ A'D MEE' 11--E SKE!'.GTI-1
REOUIR~MENTS Of FEDfq/lL SP£Clf1CAT10N RR, .. F-6210
1,1AllNG 2URFACES SHALL BE FINISHED TO ASSURE NON-ROCKING
F.T VVf"TH ANY COVER POS noN
AU.. BASE REINFORCING SlE::EL SHAU HAVE A ti/IN. "rlELD
STRENGTI-1 Cf" 61~ 000 ?Si AND 3E PLAC:::O IN TI-IE UPPER H.ALF
Cf TI-IF B/\S[ WITH 1 MIN. CLEAHANCE
MIN. SOIL BEARING \/Al...UE ShALL [()()Al 3,300 POUNDS PER
SQUARE R:X;,;
FCR DCIAJLS SI-K:M.~NG UDDEk. STEPS HANDRAILS A\KJ TOO SLABS.
SEE D,'\G NO. 2-006,
Scr TI-IE WSDOT/APWA STANDAf10 SPECIFICATIONS SEC
7-05.3 FOR JOINt REQ.JIR:':MENlS
RONl'()R(;IH(i; STEEL~ S-t-'AAATt 8ASt$ ON~'() REN"OFICIMG STEEL i'fU;! PRtCASf B,1..5.E k IHTEGAAL R&R ON..Y}
0.13 SQ. IH./FT. IN ::A:.:H DIRECTION FOO. 48' W.W. 0.15 SQ. N./n. N EACH CIIRECTION Fm 4~ CX.,.,W
0.19 SO IN./FT. IN Et,CII DIREcnoH FOR $,4" WW 0.18 SO. N/n. N DCH DIAECTM>N FOO ~ C:,,,.,.W.
0.25 SCI. IN./FT. N EACH DRECOOH FOR 6(f' W,1.,1. 0.25 SO. IN./FT. IN E'ACM DIRCtn:IN rM W" Dl,.I,..
0.3:!I SO. IN./rf. IN FJ.:::"1 DIRECTION FOR 7 1 N,1,.1.1 0.24 SQ. H/n. N t,o,I DIRtCTIOH Fm 7 1 MAY
0.3~ SO IN./FT. IN fJCH DIRECTION FOR 9 6 DIA.Iii o.n SO H./n. N £.Al).! [)IF![C'hON FCR ~ MAY
•",'.."." ., .~ ·~;k:·~ RHJ
ft:. ' •.. · :: ; • ~' ~-·;;.-i_:~:9,:,1
PA!t.lST 6,1.$( JOIM"I [ .. Tt I IOOSHlN I "' 1 ...... I
<I, KNCl cou,rry PIS.JC WOIICS
KING COUNTY, WASHINGTON CATCH BASIN TYPE 2
80
48", 54", 60" ' 72" , & 96" OWG. 2-005
NO.
-[ I'$> t,~ • r CENT<RS . ~ 9. ? Fla. MTN
n _J
S! i~?~
:Y" K I oa IQf SI Nl
n _J s i ! ...... ?-;
lt YE :iifA
"'
1· llll!N. IXI\IER
.. MRS • r CENIIRS IOTTOM fACE WITH
1• IIIH. CCHER
IO 8"'S • T CEN![R$ EKITTtJW fJa" 'MlH
1• MIH. coi,o
n _J
~ i i ..... , .. ?~
K VI' 5UB
e KNl COUITY l'UBUC WOR<S
KING COUNTY, WASHINGTON
.. -t::: .. ..., ............. .,.
-·· /
' ' ' ' '
/
\
' ' ' ' ' ' '
TYPICAi. ORl[NfATlON
fOR H"ttS5 :YiP Slfrs
lf MlH. I.T Mffl.
r I I..J
•fE4s1
11 II ,o
I.J.l:l.ttl!lliQI.Ut "'t(q]i
• AU. STE.PS at Rl,.t«:,S 16
t;N..V. DCfORMtD REBAR
c.t.ICH B&SIH SUP
OR COF'Ot:n.t[lt PROP'11.mf, ~
.,. .... s4 f Dt I 1.::i " . 1ol [L_jj -I ~ -'
11 II
t'.I.EVATION -, u Pl.AN u -"'"" CAIA:l MW £IP
,.. ""r ,·,...---=---l L
' -+-t-+ I If-_
,. r _ll.!." Cl1:.IIW<Cf:
1
1.3, ~ ,i
Mt-Of Bffi
DATE
CATCH BASIN
81
NOTES:
1, PROPRIETARY CATCH BASIN 1-WlDHOLOS AND STEPS ARE
ACCEPTABLE. PROV\D£0 THAT THO' CONFORM TO SEC. R •
ASJU COB, MSHTO M-199 AND MEET All WISHA REOUtREI.IENTS.
2. CATCH 8ASIN STEP /HANOHOlO LEGS SHALL BE PARALLEL OR
APPROXII.IA.TELY RACNAL AT THE OPTION OF THE MAN.UF'ACTURER •
EXCEPT T~T AU STEPS lN AMY CATCH BASIN SHALL BE SIUII.AA.
PENnRATION OF' OUTER WALL BY A LEG IS PROHIBITED.
3. HANDHOLDS AND STEPS SHAl..l HAVE ·oROp'" RUNGS AS SHOWN
ON DETAIL OR PROTUBE~CES TO PREVENT SIDEWAYS SUP.
4. SLAB OPENING MAY BE 24• X 2ft OR 24• DlAM.
5. AS AN ACCEPTABLE AlTERNA.ilVE TO REBAR, WELDED WIRE FABRIC
HAVING A MIN. AREA OF 0. t2 SQUARE INCHES PER FOOT MAY
BE USED. WELDED WIRE FABRIC SHAU COMPLY TO .t.STM A.(97.
6. LADOE'.RS OR STEPS SHALL EX1END TO WITHIN 10 or SOTIOM OF"
CATCH BASIN.
7. HANGING U.OOERS St-W.L BE PER"""'IENTLY FASTENED AT TOP BY
HAJ'..IGING ON STEP OR BY BOLTING OR EMBEDDING IN CONCRETE.
EACH SHAU BE EMBEDDED AT BOTTOM IN BASE.
8. ADDITIONAi.. SAFETY F"EATURES MAY BE REQUIRED IN \IERY DEEP
OR UNUSUAL STRUCTURES.
' --'
M\'lSION
DETAILS
R-3/4-9
fi .. ,.. r·-
tr ""'· , ......
II ..... i • II
~'1t ,om
'
r-~
LP J/<
PllfT.AA111C.W:Q I~
r, I AffR'D I
DWG. 2-006
NO.
~
"' i
i
i
!I
'l'
!
~
~
Ill
RWC ANO CO'..t1l!.
ACUJSTM(NT SECTION iii .. ~ ""·-«>-(lfVEUNG BRICKS 00 ~RAM ·.1 't ""'°' 0"'"""-) t· ~ri ..
4 PRECAST CONE
+ {ECCENTRIC UNLESS
" OTHERWISE $?ECIF1EO)
, 4S°, :,4•. OR 6ft . •:
I-'
-
I'/
. ._
-+ -
PRfCAST RrSv: S£C:TO.:S
rt•
stt=UOOER
CONSTRUCT IN F'lELD CHANNEL At<1
SHELF TO THE CRO*H Cf" lH[ F'1P£
stOP[ I /{${".
> .
•. ' PR[CAS"J 8A.St ,I:
IKT[GAAI. RISER
.• ' 1·-0"
I
CAAVfl SlCl<.fU FOR FQI..IHOI.T1016
' w-1. COMPACTED I>CPTM
FOR PMCAST BASE ONLY
S[PARATC CAST IN f>VrCt
81,S[ OR SEPAR1!T£
PRtCAST BAS£.
r-..01::s
2
4
5
6
8.
9
10
~"&, ~~'1'm,'l&f8YHrn~\'?,H/1'6,A!fR~0~\'m; '-Y_W, cnrec
I'~ THE WSDOT/APWA SlANUARD SPECIF:CA-IONS
I IAND"iC-LOS IN AOJUSTMEr, T SF\,T,ON SrlALL HAY[ 3' MIN.
CLEARANCt ST[PS IN MANHOLE SHALL !-iA'vE 6" MIN
(LEARAl\CE SEE Dt,G r-..lO. 2-011, '\/,ANHOI_E DETAJLS'
HANDHO_DS SHALL 3E PLACED IN Al ;iJ"!NA~ING GRADE
RINGS OR LMUNG BRICK COURSE WTH A v1N OF ON= "1ANfi
HOLD BETWEEN TrlE LA.ST STEP A\!D -._,E TOP 01 THE MANHOLE
1\LL REiNFORCED CAST-IN-PLACE CONCRE~E SH/\L_ BE CLASS 4000 ..
ALL PRECAST C'.)Nc:Rf-lt SHALL GE CLJ\SS 400D. NON-REl".!FDRCED
CONCRETi: IN CH,'\,\!NH /\ND SI l[LI SHALL B:: ClASS. 300C·
PRECAST BASES SHALL GE FURN:SHEO \~.m-1 CUTOUTS CR.
KlKJ\,KO\JTS KNOCKOUTS SHALL -JAVE 1/#V .. -:-Hl\,KJ\J:':SS 01 Z"
k% U!\JSt:D KNOCKOUTS NEED NOT BE GROUTFD IF
WALL 13 LEn INTACT PIPES SH/\,.L [3[ INSTALLED rn~LY :N
F,'ICTOH.Y KNOCKOUTS I.., \ILESS OTHER'1','ISE APPROVED l3Y fl IE
E\IGlr-..EER
KNOC>(OUT Cf\ cu-01...,T HOLE SIZE SHA J .. E.OU1\L PIPE DUTE~
DIAM. PLUS l,"ANHOI f-: \NJ'J. .. L · 111CKNESS MAX HO·_E
SIZE SHAL_ BE J~ FOR 4.'!' f,!J>J'·HO_f-: .ct• 1·cR 54• IAANHGLE
48' FOR 6Cf M.H MIN. DISTANCE BETWEtN HOL!.:S SI IA_L B:: 8"
MANHOLE R1~~c;s /1NIJ COVLRS SI !ALL B:: IN ACCO~DA\ICE
WITH SFC 7 IJ~ f\ND MEET T"li: STRENGTH REQI..., REMF\JTS
m 1=EDERAL SPECIFICATICN RR-F-621D. r/1\llr-..G SLR'ACES
Sf-ALL BE F."JIS"1E,J :() N3:'llJl~F r-..cr-..-ROCKING Fl: WITH AN"'
CO\/FR PO~ I ON
.A._L BASE REINFORC NC; s·1 Fc:.l SHALL I-IM,1 A Mr-.. YltlO
s-RENGTH OF 60.000 PSI /IND GE PlACED 1\1 THE UPPE~
OF THE BASE WITH 1 i',11N ;·;. FN{,\NC:...
l'CJR I !EIGHTS OF 12' OR U:SS t,% SOIL t:lll\l{l~JG VA!.L::
Hf\l F
SHAI !:-OIJ,\L 3 3:JO POUMCS PER SQUARE FOOT 1-UI~ HI IGW~'.
0\'EH 12' r/ r-.. SOIL BEARING VALUE SHAl l 1--::0UAL 3 &JO
POJNDS P:C:R scu:,rn HXlT
FOR' DETAILS SHQININC~ (;rwJE l~IN\-' LADDER, STEPS. HN~o-:rn ,-JS
f',/\1'.• HJP S....A9S S:CE W/.3. r-,o_ 2-011, 'MANHOl 1-Dt.:IAILS"
SEF THF: WSOOT/APWA STA.t,DARD SP::CIFIC . .'.1.TCJNS SFC
7-05 3 FOR JOINT REOUIREMENIS
'i
!
fltff"ORCNG STtEL ~ PR£CAST ~ f. M"[GRA,l RlstR OHt. Y)
8:~~ ~: :Jt : EAD-1 =~ ~~ ~ E:tt
;\
'ff;·
L-R[WORCING ST££L (FOR SEP.IP.AT( e,.is.e:s OfojLY)
0.23 SO. N./n. N tM::t1 Dlttcnort FOR '411"" ~
0.10 SO. jN./Fl. N OCH OIR[CTIOH FOR 5,4'" C..W
O.~ so '111./Fl. N OCH tlR[C'OON FOR Ff tw,,1.
! H'~7P::sk~;_f~ ~7-~
~.1,.,-.-·<t ....
'·
PRtCAST 8,1,S[ Ji0Wr
KNl COUNTY PIJBUC WOA(S
KING COUNTY. WASHINGTON
O 2 5 SO. IN /fT. IN EACH OftCTION roR f;/J' ~
DAlt
.MANHOLE TYPE 1
82
"""""' ! Br ~
48", 54", & 60" qrp-2-007
il
s:
%
~
i
~
~HC ANO CO'vtR
M>-ADJUSTl.l[NT SECTIOH
tLMLING 8AICKS OR GAAllE
.t.._ . ...cs OP10W.}. :~
,..
!:<lilt>-ST£PSl
l• / ::f ~ -CAST CONE ', ~ -. J ._ (ECC[NlRlC UNLESS
4( OR ~· --+,. •
OTWERWISE SP£C1Fi£D)
--+
~ ·v PRECAST ~S{R Sl:CTIONS
TOP SUi8 :\ et L'Oll£R ..
77" OR Q6" ""'":
>LOPE I 1
1· ~·· CONSTRc<:T "' nno ""'"""
~
/r /FT ~ . _·. .t.t+O SH[Lr TO UIE CROWN
) ' ~ TH[ PIP£
. '•· '.' ..
. • ... I i;· ,. . .• I-' I """"'"''" • • ., ;. r IHT[(;FW. RISER . ..
~ • 2·~
"i GAA'r'CL B>.CKFILL FOR F~TlONS
j 6 MIN COMPlrCTED DEPTH g FOR PRECAST £1,1,$£ ONLY.
NOTES
2
3
4
5
G
MANHCLES SHALL BE CONSTRUCTED IN ACCORDANCE VITTf-1
MSHTO M199 l,'NLESS OTHER'NISE SIIOVVN CN :>LANS CR NO!t.D
IN THE WSDOT/APWA STANDARD SPECIFICATIONS
HANDHOLDS I~~ ADJUSTMENT SECTION SHALL H.AVE '$' \11N
:~LE1\R/\NCE SIEPS IN MANHOLE SHALL HAM 6" MIN
c;._EA.~C:: SEE D1\G NO 2-01' 'MAf\1-iOLE DETAILS'
HANDHOLDS SHAU_ BE :>LACED IN ALTERNATING GRJ\D[ RING:i rn LE\IEUNG BR!CK CCURSt: VVITH MIN. OF or-..E HANDHOLD
t)ET'JVEEN l"HE LAST STEP AND THE TOP OF THE VtANHOLE.
ALL REINFORCED CAST-,N-PLACE CONCRETE SHALL BE CL.ASS 4000
NON-R!::INI-ORCED CONCRETE IN CHANNEL A.\/D SHELF S-iALL BE
CLA.SS 3000 ALL PREC.:.ST CO'\ICRET[ SHALL BE cus~; 4000.
PRECAST BASES SHALL BE FURNISHED V.'ITH CUTOUTS OR
KNOCKOUTS KNOCKOUTS SHALL HAVE WMl THICKNESS OF Z:
MIN. UNUSED KNOCKOUTS NEED NOT BE GROUTED !F
WAIi_ IS IFFT INTACT PIPES SHALL BE iNS'ALLED ONLY IN
FACTORY KNOCKOUTS UNLESS OTHERWISE APPROVED BY HIE
ENGINEER
KNOCKOUT CR CUTOUT HOLE SIZE SHALL EQUAL PIP[ OUTER
DIAM PLUS MANHOLE WALL lHICKNESS W0:: HOLE size SHALL BE 60" FOR 72· lvtANHOLE. 84" FCR 9~ MANHOLE
M'N DISTANCE BCTWEEN HOLES SHALL BE 12''
MANHOLE RINGS A\JD COVERS SHALL BE IN ACCORDANCE
VVITH SEC 7.05 ANO MEET THE SIR!:NGTH REQUIREMENTS
OF FEDERAL SPECIFICATION RR-F-6210 MATING SURFACES
SHALL BE FINISrCD TO ASSURE NON-ROCKING FIT WfTH ANY
COVER POSITION
7. All BASE REINFORC:NG STEEL SHALL HAVE A M:/\. YIE:..D
STRENGTH OF 60.000 PSI AND BE PLACED IN Tl-£ U~PER -IA_F
OF THE BASE \11/11-1 1 MIN C'_EARANCE
8
9
10
FOR HEIGrTS OF 12' OR LESS MIN. SOIL BEARING VALUE
SH.a.\LL EQUAL 3.300 POUNDS PER SQL,ARE i:-ooT FOR 1 ·EIGI ITS
OVER 12' MIN_ SOIL BEARING \/AlUE SHALL EQUAL 3.800
POU/\JS PER SQUARE FCXJT
FOR DETAILS SHOWING GRADE RING, LADDER, STEPS. HANDHDLJS
MD TOP SL.A.BS. S~E ONG. NO 2-011. "MANHOLE OETAJLS.'
SEE T-iE WSDOT/APWA STANDARD SPECIFICAT!ONS SEC
7-D5 3 rOI~ .JOINT HEOlJl!H:CMl::r-..TS
,0. •fOR SEPARATE SEPARATt CAS'l'-IN-PIJICE
"!. CAST-IH-Pl,i,C( BASE OR SEPN1.Al[ REIN.FORCING Sll[L FOR PREOST B,t.SE & INll'.CRAL RISER ONLY)
'lo ONLY PRCCAST ~[. 0 24 SO. IN /H IN (EACH D1R:£C1ION roR 7 1 D~ 1 0 20 SO IN /n IN [>.CH OIR((;JION FOR >16" OW
!
~
L-RU~rORONC SlEEL \FOR SEPAAATr B,6,5[ ONLY)
(i)
gj~ ~ :t~~· : ~ Bl~~iv~~ ~~ ~J ~!{
,.,,, ;]
fo! ' • ).:t .,,,.,.,,_ r;/ RING
«i,:-::-'.=~·;e,::j
PRECASt' BAS[ JOIHT
KNO COUNTY PU8UC WOll(S
KING COUNTY. WASHINGTON
DATE
MANHOLE TYPE 2
83
R£V1SIOM
72"
I BY I APPR'D I
& 96" DWG. 2-008
NO.
~
TOP~ ~•~l-'1H<N~'t ..
~ •' ·,
RlNG -!: tO'it~
AOJUSlMC«! Sl:CTIOO
(LEVELN; 9ft!CM.S CR {;AAOE
AiHGS OPTION,l,L.).
l(l
I
'r. ,;, w
X
. . ~~ STE?.l00tJDER2
~· .. ~·""'-.'""''-'-'·':."...;°"::::...':,''-!'-~~
i 1-.... ~_.:::..:~?""?r==1"i--~o~~c,1 ~
',i:.
• . • PMCAST Mst 6:
_. 1 INTEGRAi.. RISER
1"-{1' FOR 4r' .~ 6: ro" ~-'f •. 2'-(f f"OR ,r ii: ~ DW.I.
! 9 SfPAAAT[ C.ltST IN Pl.AC[
iJS ~ • roo SEPNtATE 8ASt OR S[PAAATt
~ ~ ~~-IN-Pl.AC[ PR[CAST l!AS(.
) ~ REINrORCING SITEL (FOR SEPARATE BASCS ONLY) jS' 0.23 S<l. 1N./Fl. IN tacH OMCTO\I FOR '48'" 0~ ~ . 0.111 SQ. IN./FT. IH [ACH ORCTIOH Fc,l 5,4• OIAM
GRAVEL 8ACK11LL FOR FOU~OATIONS
6 YN. C-0-WNctro oc.M~
FOR PRECA$l 8'SE ONLY.
r,,mrs
f, 1/\ '-JHCl[S SHA....L BE ::::ONS"TRUCTF] IN /\CCORDA\ICE WITH
AASHTO M199 UN: FSS OIHU;:'NS[ SJ-KJ/,.1\1 ON PLANS CR
f\OlE) IN IHE WSDOT/APWA ST.;J\IDJ'..RD SF'ECII ICi\TCNS
2 H.A.ND~Ol.DS IN /\DJUSTMENT SECTION S-f.llJ...L H-\\'l S' Mlt\
CLEAR/\NCE STF'S IN M/\l'JHOLE SHA1...l H ,; \r, 6• MIN
Cl.EPW\NCE SFF !)J\f;_ NO 2-Cl1 '., ·t..,\ANH()L.E CETPL.S
1-W\1DHOLD5 SHALL 3E PU..CED IN AL TERNA Tl'-J(C GRADE. RINGS
rn LEVELING BRICK COL)RSE '-,\'!TH i\ Mlt\. Of CNE HANDHOLD
BET1.1\IE'ff\' ··-iE U..ST STEP A"-jO Tl-:E TO-' OF TH:-rvt<;NI !OLE
3. ALL .RElt\FORC:Ff) Ct,ST IN---P ...ACE CONCRETE S'-lf'.U BF CIJ1S':> 4000.
4.
5
6.
7.
e.
9
111
NON KE:INFORCED Cet-JCRE""E t\ CH/•.NNEC.. 1\\/D SrlELr'" SHALL BE
CLASS 3000. ALJ PHt.C.A.sT CO\JCRETE SH.ALL BE CLASS •1000.
=RECAST BASES SHALL RF fUR\JISHED WITH CJTOIJTS CR
KNOCKOUTS :<NOCKOLTS SI-I.PL f-AM \~i'.AJ...... iH!CKfESS Cf '2"'
MIN UNUSED KNOCKOL TS NEED NOT RE c:;i~(XJTED IF
WAJ...L IS ...£FT INTACT PIPES ;C;H1\l_l_ G[ .NSTALLED ONLY If\
FACTOR.v KNOC:KOU'.S UNLESS OTHER\NSE APPR0v£.O RY 11---JE:
LNGI\JEER
K.'KX::KOJI CR CUTOl.J"""" HOLE StZE SHAl.L FOU/\L PIPE 0.Jf-=R
DIAM. PLLS IJ'..-'\\JHDI I_ V1.1NJ_ THICKNESS MAX. hO~
SIZE" S-!ALL BE 3 6 IOR. .ta"' 1.4 H., .t2" FCR 54"" MH 48"' rrn
6(f' MH. 6 6 F(~ 1'1" M H::.t. s.r Fa< 9 C r.: H MIN DISTANCE
BET'NEEN HOLES SHAl..L. BE H H)I~ 4 6. 54•, MC 6 6 MH, 1 °L
Fffi 7 1 .AJ\'[) 9 6 r,._1;11
MANHOLE rw ... c;s mo CO'ERS SHALL BE IN ACC' .. OPCJJ\NCE WflH
SEC. 7 .05' PND M::F.T Tl-E S"!RENGTH REOUIRE\1ENTS
CE FEDER.Al SPECIFICATION RR-r-6210. MATlNG SURFAC::C:S
SH.ALL BE FINISHED 1D ASSURE NON-ROCKING FIT WITH ANY
C\'1\IEF~ f-'OSI ! ION
All B.ASE REINFC>RCING STFF_ SHAll H :._r,..1 /J.. MIN. YIELD
STR[J\J(.,;n, ()F 60.000 PSI mo BE PI/\C[D IN -:llE UPPER
OF THE SASE'. WITH 1 MIN. CLEARA\ICE
FOR HEIGHTS Of 1:t CR LESS MIN. SOIL BCAR:ING VALUE
HALF
SHALL EQUAJ... 3.300 POUf\DS PER SQUARE FOOT. FOR HEIGHTS
O.ffi 12 MIN SOIL BEARING \IALl,'F SKALL [QUJ'-1 3.800
POJNDS PER SQUARE FOOT
FOR DFT/11l_S SHO\'VING GRAOE RING. LADDER, STE~ HANDHOLOS,
mJ TOP SLN..1s_ SEE D/..G NJ. 2-c,,, ·r..v1\HCJLL:: DHAlLSW
SEE THF WSOOT/APWA ST.;J\IDARD SPECIFICATlONS SEC:
7-05.3 FOO. JOINT REOUll""iL.Ml.:NTS
to J 0.2~ SQ_ IN./n. IN u,C;tl [)IR((:1'~ FOR ed [)w,t
1 ,i!; 0-" SQ. IH./n. IN f,,CH OIR[CTIQH FOR 7'r DIAM. l ~ 0.3', SO. ~./Fl. IN £>,CH Oltt:C'TIOO fOR v,t; CM.tM.
REH'OOO~ Stm {FOR ~CAST e,..s[ & INT[GIU.I. RISCR Of.11.Y)
,) ~ SO. IN./Fl. \" OCH OO!tc:TIOf,j FOR 411" OWi.
~
(j)
~ .
NG
.
PRECAST B,l,.S£ JOINT
KNCI COU',/TY Pl.a.JC WOll(S
KING COUNTY, WASHINGTON
~J, f6: ::;'H i~ ~ =~ ~ ~ ~-
0.2• so. N./n. , EACH wrCTJOH Fm rr w,,1
0.29 SO. 111./n. \" £>.CH DIRECTION Fffi id" 00,N .
om
MANHOLE TYPE 3 48"
84
-
' 54" ' 60",
i., 1 ...... 1
72", & 96" DWG. 2-009
NO.
NOTES
1. MANHOLES SHALL BE CONSTRUCTED IN ACCORDM~CE \MIH MSHTO
M199 UNLESS OTHERWISE SHOWN ON PLANS OR NOTED IN THE
WSOOT/;JJWP. STANDARD SPECIFICATIONS.
2. HA\!DHOLDS IN ADJUSTh1ENT SECTIO~l SH/'.LL HliVI': J' MIi\
CLEARANCE STEPS IN IJANHOLE SHALL nAVE fi MIN
CLEARPJ'.JCE SEE DN3. NO 2-011, 'Ml1NYOLE DETALS'
3 MANHOLE RiNGS AND COVERS SHALL BE IN ACCORJANCE VflH
SEC. 7 CS AND MEET T"iE STRENGTI I REOUIRLf,-'.l-N!S DI--
FEDERAL SPECIFICATIOI\ RR-F-G21D MJ•,TING SUR;:::ACES S·I.C\LL
BE FINISHED TO .C\SSU~C N'.JN-ROCKING FIT WITH /\NY COVER
POSITION
4 ALL PRECAST CONCRETE SHALL f£ CLASS 4000
5 FOR DEiAILS SHOVVING GRADE RING l.AOOER, STEPS HANDHOLDS
AND TOP SUBS. Scf D./\/C~ N:J. 2-011, •MANHOLE DE-A LS.
6. NOT Fen USE iN --:-RAFFIC BEARlNG AREAS.
<I.
•8'" OWi. RISEfl: SECTION
GAArTED TO PIPE
SY rASRIC".lTOft
(i)
<I.
El EYATION
KNl COUNTY PUBLIC WOA(S
KN3 COUNTY, WASHINGTON
_ ..
RE!Nf"ORClD CONCROE
PF[ "4s" WIN. DlilM.
ii
~
ii
)l
STEPS
RING MO CQ((R
F'RECIST CON£
(ECCENTRIC Ut4£SS
OTHERWIS.E SPEC!f®)
Pf<fCAST RISER SECTIONS
'--------',-\?>----wEl.D f:ELNF'O/'fClNG STEEL
SECTION A A
DA1E Rl'V1SIOH
MANHOLE TYPE 4
85
Of J'OltflS
BY APPR'D l
DWG.
NO. 2-010
~
,.
r=-i _J
Si !.....J~
+I' y ._ W: I9P 51.M
' s ! ~?.!
11'. TOP Sl.AB -,
_J ~ ! !_.__._._ ? ~
.. UJt S:1,¥1
KNCl COl.fflY PUIUC WORKS
KING COUNTY. WASHINGTOI-I
h BARS O 6 (:£HfEAS bcrrrow rACE
f MIN COYER
" """ • 6 <£"1[RS BOTTON FACE
1' ~-COVER
I& BAAS • -r ctNT!RS """°"'"-' 1" WIN_ COV[A.
..
• AU. STEPS &: RUNGS
--r DW,I. GN_V REMA OR
toPOt,.Yl.l(lt PROPn.ENE.
1o[8""§11
II _;J " u u
""'""""' -e],
MN:tDE srrr
~
N'._:ILS
:iRo:iRl[~A~Y Vi\NHO:...E HANDHOLDS ANC STE;:,S
,\IIE ;\(;CE?'.-,\tU.C PROV10E0 TIIAT TI--EY CO\FORM
TO SEC R. ASTM C478, AASHTO Mt99 A.ND
M[[T .AU WISHA REOUIREr,.'EWS
2 MANHOLE STEP/HANDHOLD 11 c;;; SI 1.,\LL BE
P/\RAI IF OR /\F'PROXIWdLLY RA.CIA:... AT ~HE
OPTION OF fr:: MANUfACTU~t:R. EXCEFT THAT
Al I :_;r!---.PS ~! A~Y MANHOLE SHALL BE SIMIU-R
PENETRATION OF JUTER 1/1-'A_l BY A LEG IS
PROH!81TED.
3. ~DHOLOS f'.\D srnrs SHALL HAM "'oAop"
~UNGS OR PROTUBErl.ANCES TO PREVENT
SIDEWAYS SL! P
4 UDDLI\~ 01~ ::CI l.::YS SHN.l ::':XTENC TO WITHIN
16 01-BOTI:Jr-..-1 Of MA\"10LE
5. ~ANGING LADDERS s-."',LL BE :-irnrvV,NrnTLY
FASTE\:::O 1\T TOP 6Y ,"lA\GING :J\ STEP
OR BY ~Olll\3 OR :CMB:CDD·NG IN cmicR.aE.
EACH SHAL_ 3E EMBEDDEC AT BOTTOM , N ~
G. ADDIT :JNAL SAFCTV rEATUR[$ MAY 1::H: ·{U'llkED
L'.I v:::.:Y DE:CP OR UNUSt.1.1\L s-RUCTIJRES
R•J/4"
·t l,'j
,.LI I ~~~ ~[[d]i
f8 CALV. om>•E> HEVATION ""'"
.Y,t,NttPI f PB9P ffllHG SUP
,· ,.. .-r C1
r
,. R[BA,R
fiSl!iltE Bit£
....
MANHOLE
86
ll£VISION
DETAILS
' __.
""""
11 GAl,.V.
swoon<
STtEL
' ~\ 3/4"
P8[£':f!R!C4TIP I MKtf8
~
i •
..
rmJl· 2-011
"
,:i..,._.,.~ !\ND (;R.1,T'E
SEE SEC. 7.05 ?N)
APPUCA!!Ll'. DWC-$
6" RISER SECTION
\OTES
CURB I\_ET TO BE CONSTRUCTED II, A.CCORDANC::: VVITH
ASTM c,178 & C890 IJN_ESS OTHER'NISE SHOWI\ ON PL!l..NS
OR NOED N THE SiAI\J.2\f-m SPECIIICAT:ONS
/JS AN ACCEPTABLE ALTERNA-:WE TO REBAR, VVE_DED WIRE =Nrs.1c H1Wlf-JG /.. MIN r,RFf\ OF ,J 1 '.! SQU/\RF INC-ffS
PER FOOT klAY BE USEJ 'WELDED 'NIRi:-: FABRIC SHALL
COMPlv TO P1STM AL97 \1,'IRE =A5q1c SHALL NOT BE
PLACFD IN K,\OCKCil)TS
3 Al_l RFINFORCED CAST-IN-PLACE CONCRtff: SHALL :'if:.
C:..ASS 4000.
1 #3 BAA HOOP -------~ ~ 4 PRECAST BASES SHALL BE "URNISHED WITH CUTOUTS OR
2 ,1 BAR HOOPS ~
11 ~ EACH CORIۥ
IJ BAA. EACK SiOE.
TOP &: BOTIOM
1-,·J e.<.R ACROSS sonm.1
@ KNG COUNTY PUBLIC WORKS
KING COUNTY. VVASHINGTON
'~
l
12" RISER SECTION
PRECAST BASE SECTION
O,,EASUREMENT AT THE TOP
UF" f'HE BASE)
"'"
CURB
87
KNOCKOU'S KNOCKOUTS SHALL HA'JE A WALL TH CKNESS
OF 2" MIN .4.LL PIPE SHALL BE INSTALLED 1M FACTORY
:.JRQVIOE::: KNOCKOUTS UNUSED KNCCKOWS NEED NOT
3E GROL TED IF WALL IS LEFT INTAC-
KNOCKOUT OR curou-HOLE SIZE Is EQUAL TO PIPE OUT::R
OIAM PLUS CURB INLE::T WALL 1HICKNESS
ROUND KNOCKOUTS VAY BE ON ALL 4 SIDES VVITH M•\X
DIAM or 1/.
THE MAX DEPTH FRO\/, THE FIN:ShED GR4.DE TO THE
PIPE INVER"'." IS s·-o".
8 THE TN'ER ON THE SIDES OF THE PRECAST BASE SECTION
AND R'SER SECTION SHAL_ NOT EXCEED 1 /r /FT.
9 CONCRETE INLET FR4.ME A~J GRATES S,-iALL BE IN ACCORDANC:C
V\'1TH STANDARD SPECIFICATIONS .4.ND lv'iEET THE STRENGTH
REQUIRE\lENTS OF FEDERAL SPECIFICAT:oN RR-F-621D
l\11A.TINC SURFACES SHALL BE ::1NISH:':D TO ASSURE
NON-ROCKING FT WITH ANY OTHER COVER POSIT:ON
10 FRA\,1E AND GRt..TE MAY B::: INSTALLED VVITH FL.l..NGE 00'.NN
OR CAST INTO RISER
RE\.~SIW
INLET
RY I APl>"'O I
OWG. 2 -012
NO.
I I/ff' 1'YP 2,,;:
7/ff' Tl'P. 'SLOT
,6r LETTERS RCC£SSEO
T BE nuSH4
' ' '
~-... ~!ITT10,IO,,,~.,ffGIIJ.I
.tl.-
TOP YJEW
2J J/4" ~
see
[)[TNl
"' ;,
• I I ~I .j
u ~ :u===i I i •• ,,,, := "''" -t I J I
,.
:,
7ff 3·· 5
23 1/'f
SIDE VIEW
=,-:,
··-I!_:__]
$LOT DETAn ... ""'"
~ _JLu.-
(i) KNJ COUITY PUUC WOR<S
KING COUITTY. WASHINGTON
,.
~·
'
,,.
~
BOTTOM YIFW
17 J{,:'
J/~ L:=
17 1/'!_
ENO YJEW
NOTES:
7 1/-'" FOR i,.,.t.'.:-i-,;>;-:;
CWIW<C[
TMS fWI" 1• THICK
{NP. 4 P\J,CES)
f'LIIJ'i!S 1 'V~ TttlO!.
"" "''"'
W:$ I 'J/tf ln,Ci,.
, THIS AAU.
liVnN:. PAOS
! -3/4" X I J/4" X 1/tr
SLOT FORMED MID RECESSED FOR 5/tr -11 NC X t" SOCKET
HEAD {ALLEN HEAD} CJJP SCRE'N
2. CRATE SHALL BE CAST IRON PER AStM ,ll,,48 CLASS 30 UNLESS
OTHERWISE SPECIFIED
J SEE SEC. 7 .05.
4. THE WORDS 'PROPERTY OF KING COUNTY' SH.AU.. BE OMITTED
IF CRATE IS ON PRNAl£ SYSTEM.
DATJ: -BY I APPR~ I
STANDARD GRATE 'Wi~· 2-013
88
,..
., -l!VEL P~ 16 -J/4• X 2 1/.(' X 1/t{
' -'-...'. '/..
I __J = -'--11 s.' J
A w
Ir ~ n
I
,.
~ SEC NOTE 1
Jl ...........::'I
~
L
-L -----i
~. -
~
~ I
1e"" k. 2, 9/16"
l+1/32'". ~rr NP.} 1r ~
~ = ~~
1 '
te X 22" OPENING 11 I ~
17 J{.4 X 23 J{.••
(+1/Jt". -Cl TYP.)
__ ,_,·
SEl:TIQ~ A A
NOTES
1. DRILL A.ND TAP FOR AND PROVIDE. W\/0 LOCKING B:JL TS 516-11 NC STAINLESS
TYP[ 304 STEEL SOCKET HEA.D (ALLEN H:CAD) CAP SCREWS 2."' LO~JG V,'H'::N usrn
WITH SOLID COVER !DWG NO 2-015) ffi \VHEN SPECli="IED BY E\GINEER
2. FRA.ME MATERIAi... IS CAST If.I.ON PEI-{ ASTt.4 /\42 C,.ASS .30
1. :•
,..,.,
L_
GUTTER _7------
VERTICAL CURB
SEE NOTE 4
I
L -,r------
WIT<R _/
FXTR\ /PED Cl 188
93: N.OTl. 4
T
3. St:.T FRAME TO GRADE AND CONSTRUCT ROAD AND GUTIER TO 3:: FLUSH vv-rn FRAME D.tlC HE\/1.SION BY I APPR'D
4 SEE SE.C 7 ,05
(i) KING COl.NTY PI.IBUC WOAKS
KING COUNTY, WASHINGTON
STANDARD FRAME WITH VERTICAL OR
EXTRUDED CURB INSTALLATION
89
C[M{Nl CONCRETE CURB
~ CAl0-1 El.lSIN '.\'A 1
£X1RUDED ClJRe
~ CATCH BASIN \'i L' L
DWG.
NO. 2-014
~
..
A
~
0
JJ __ :.L<
z 3/F5' r 2 JJa" l '!,/'fJ t::i
I I 1 ··-1 f ~
=-<:> <:> g ii ====b~ <:> <:> <:> <:> . <:> <co>
~~<>-<:> <> <::>
-~ <> <> <:>-<:> :== <:>-<:> <::>
~~~
~d
R•l/4"
SfE NOIT 2
1 /t' LETTERS
RECESSED TO BE FLUSH~
LMuNC PAD
8 -1/ff' X J/4" X 1 }/'4"
PlAN COVER
"' "-__:/
::=t~~ -g
" •
-cccc=---J''•
---====;] f ~
h
NOTES:
1. USE 1Nm-: ::-~ME (DWG. NO 2-014) D~ILL:'D A'.JJ TAPPED ::-oR
!.OCKING BOLTS
2 JSE 1NfTH T<i\O LOCK'\/l.; LlOL TS 5/8" -·1 ', t,C STAJNLESS STEEL
TYPE 304 STE:"I SCCK[T f--<EAD 1AL_EN HS'\DJ G'lf' SCREWS,
2• LONG.
3. W.TER!AL iS C.~ST f"-(0\/ PER A.Sm A.4.~ Cl :1ss ·30.
4. :-::.lL SEC. 7 05 . -,r :
. ---:yJ :' :,] ff/h!2+::*7° z " -9fk»7/kk~ -
-~ . II I ' ,;,· I
~I L~ {, l_ ·-~ ..
::J '""""° ' . SECTION A-A
THE V110R0S 'PR'."JPrn IY c::-KlNG COUNTY' SHALL BE OM:TIED If
COVER IS Qr, A PRNAT( SYST!:M
KNCl COlM'Y PUBLIC WOlf<S
KING COUNTY, WASHINGTON
90
DATE
SOLID
R£Y1SION
COVER
I 8Y I APPR'D I
DWG. 2-015
NO.
,..
a, ~
1/~
:il ~
' ~
A )!
a,
DRIU. a-TAP TWO vr -11 NC HOLcs.
THRU FRAMt
i..£V[LIHC PNJ
7-!/tf' X 3/4~ X 2 1/4"
(m>.)
MIN OfW1 ON
THIS s«
fl.&,
r--L HOOO AITACKES AS ...,.,.
Ir---~\
1 l :J ur ./.I ,1,-f ,,,1,· 11
,., ,!,r " "' :::-L"l:I . ::-S.-
~r~
L~_-1£:;_ .
SECTION A-A
,.,
~
,¥ rw r-11 ~
' I
I I
I
I
' " C 1: C --
I .• I
I ' L-> ~
JG1.-
SECTION B-B
NOTES:
S[[ NOTE J--...
2: -1" OWol. MOLES
roR J/4" BOLT, ....S.H[R.
,t N\.11'. 5[£ f"°1I: 4
1 . MATERIAL IS CAST IRON A$T"4 A•B CLASS 30.
2. SEE DWG. NO. 2-018 FOR \/.A.NED GRATE.
HOOD DElAIL
_;:
L__L
_;:
SECTION C C
>.
il ' -
~
J. PAlTERN ON TOP SURF'ACE OF' HOOD SHALL BE .3/1 S-NON-SKID DIAMOND.
4. BOLT, WASHER. ANO NUT SHALL BE GAlV. OR CORROSION RESISTANT.
S. SEE SEC. 7.05.
om REVISION BY AP'PR"O I
~ KNG COlAIITY PUBLIC WORKS
KING COUNTY, WASHINGTON THROUGH-CURB INLET FRAME DWG. 2-016
NO.
91
I
V
Pl..ANT!NC
~; ~ > --~
F?
I F
>=F
/a
_, -
~
V I <J
STIIIP OR SroEW,IJ,.K
~~
>
!p "'" k p,=
" " F~ >== ,. ~
>-F '""
---
flt,tL
V
-~
~ DUMIIY JOmTS
V
--
B u
--
!ii e•
j1~ ~l
CURB-~ r--------------~~-DUW1' JOI~
NOTES:
CUTTIR·7--------
CATCH e.-51H
SECTION A-A
,;,
1 SET TO GRADE AND CONSTRUCT ROAD AND GUTIER TO BE FLUSH WITH FRAME.
2. SEE SEC. 3 04' FOR JOINT REQUIREMENTS
~~ •. t
,
GUITER_/
DATE
CA.lCH B,l,SIH
SECTION B"E!
REVlSION UY I APPR'D I
~ KNQ OClUNTY PUBUC \1\1'.JRKS
t<ING COUNTY. WASHINGTON
THROUGH-CURB INLET FRAME & GRATE WITH
VERTICAL CURB INSTALLATION
92
DWG. 2-017
NO.
' ' 1-Mo131 , ~, . ) II ._ __ ..
bJ) !~ ! NOTES:
;,= ;= ;:= = 1 SELf-LOCK VANED GRATE LIANUfACTURER SUBJECT
TO APPROVAL BY ENGINEER.
~ 2 US[ WITH "TWO 1..0CKINC 130L TS 5/8" -11 NC
? STAINLESS TYPE .504 STEEL SOCKET HEAD ~~ ):= ;= ):= ;= (ALLEN HEAD) CAP SCREWS 'i" LONG. NOTE ~ ~ I ~ SLOT DETAIL.
;:=;:::: :-l=~ ):= ;= ~ ,. MATERlAl IS DUCTILE IRON ASTt,4 A536 GRADE e ~ -80-55-06. " 4. ·oUTfAlL TO STREAM DUMP NO POLLUTANTS"
" MAY BE LOCATED ON BORDER AREA. -= l:=..::= =a= 5. sn:: SEC. 7.05.
~ ~ . ----""~·~·=-, BE OMITIED JF GRATE IS ON PRIVATE SYSTEM.
r---, 1--Ernw1 r---, r >. ' ' ' ' !
I
~ L&n.Ni PAO 1/3" X 3/4• X .! 1/,4• [y,. -
..... I fOR SLOT [)[TAil SE[
2J 3/4-OWC.. NO. 2-01!1
.El.Al:l
·=~ ~ ~
~ / r, /, r, r, r, r, / ,,.--. I t. t. : t. ' t. ' t. ' l ' l ' t.
f I
El fYAIION
I DAT[ I REVtSIOH. 1 .. 1 ..... 01
(i) KNl COIMrY PUIIUC WOFl(S VANED GRATE DWG. 2-018 KING COUNTY, WASHll'IIGTON NO.
93
I
(i)
LMLING P,A.D
6 -J/4' ;: :, 1/4." )( 1/13"
' " ~
~
I
A
1 /';!' LETTtRS -
RECESS:£0 TO
BE FLUSH.
"'
" '' I 1111
~
0 , ~~ ::==:::: i
111 _ ---~i
'' . ---~ :===:::::j.,: I~ 0
' ;cJ
~ ::==::I
" ~---~" " __ ____I_~:-';~---~ "
,JW L,,;~
lYP, ' 1Yf'
!l___!h~
£L.6fj
-~, •
A
St
______:j
-~~ I
__J
s\
c__ __ _ ~ S3J "' ...
I ~:-f I .1
SECTIQN A-A
~
om
KNl COUNTY PUBLIC WORKS
KING COUNTY, WASHINGTON ROLLED CURB
94
NOTES:
FRAME
MATERIAL IS CAST IRON ASTh1 A48 CLASS 30.
2. SEE SEC. 7.05 .
3. THE WORDS ~PROPERTY OF KING COUNTY" SHALL
BE OMIITED IF ON A PRIVATE SYSTEM
4. NOT TO BE USED ON THICKENED EDGE ROADWAYS.
' ' . R£V1SION ~----I In I APPR'D I
& GRATE OWG. 2-019
NO.
!I
~
2'-ff
~1-l i
«' 1 "1/ , \r, m i1
~ ;11
§:1
~sl
"::
I
1{ I ~
~
I :s ~ I , ! ~
I ~ !
A I ! ~
~ LJ I Iii I
I ::
-
1t V
v~ Vo a:~
~-----~ s
" ~---~~
::==='.t ,--~c==:J~
~~~~~
--,---,•
gl" .,,,
~ :.
fii,t!
KING cou-nY PUBLIC WOAKS
KING COUNTY, WASHINGTON
I
A I
LJ
I
I
~
ROLLED
P.G.C. SIDEWALK
TRAN$1TION
FRONT EDGE OF
FRAME FLUSH ',tr'in--l
STREET /GUTIER
SURFACE ]
_,___,_,
SECTION A A
NOT::S
1. SET FRAiv1t: -o GRADE AND CONSTRUCT ROAD 1\NJ CURB "'."::) BE:
FLUSH .A.T FRO'\ T At'.D BACK OF ;:RAVE
2 SEE SEC. 7.05.
~ -HE' VVDRDS ""ROPERTY OF KING COUNTY' SHAL_ 8:: OMITIED
Ir GRATE IS ON A PRNA l l::. SYSTEri.1
4 NO-TO BE L..SED ON THICKENED EDGE ROADWAYS
-BACK ED<iE OF fRAIJ( MN
1111TH BA,Ci< FA.Cf. OF CURB
[ ---Rr'IISIOH BY I Af'PR'O I
CURB FRAME & GRATE INSTALLATION
95
DWG. 2-020
NO.
(i)
"'
~-,Jn~~
~~
'i~~~~~, NOTES:
A 1. MATERW.. IS CAST IRON ASTM A46 CUSS 30.
2. SEE SEC. 7.05.
3. THE V\ORDS 'PROPERT'I' OF KING COUITT'f' SHAU
BE OMITTED tr ON A PR1VAT£ St'ST£1,1;_
~~
~. --·· ~
N -"\ ~rw
KNQ COUNTY PUElJC WOfl(S
KIHO COUNTY, WASHINGTON
11 1{.r m
.f?J.&j
,,.
I ,· ,,.
SECTION A-A
I 1··nrr 11
,·1--
--~
~
SECTION a a
DATE -1 .. 1 ...... 1
ROLLED' CURB VANED GRATE
96
emf· 2-021
(i)
""'" ,,.
A
__J
'.!!.
'll'llh ~ ~ __'.:I
1 J/tci-r-,
N
S£CI10N A-A
KINCI COUNTY Pl&JC WORKS
KING COUNTY. WASHINGTON
DAWO un1"c HCU 4
11 1.l1 t/' f .'c'.\lo Cl.NT£R
RPI I DOWN QfTAU
'/'" 'S.i r-J ~T SO.
~_j~ -,5.
• '.!!. ::, ~
covr~ ~ KIO DESIGN PETA!L
$
NOTES:
USE Wllti THREE LOCKING BOLTS 5/8'"-11 NC STAIN~ESS TYP[ 304
STEEL SOCKET HEAD (ALLEN HEAD) CAP SCREWS t" LONG. DRILL
HOLES SPACED 120 AT 11 1 / 1 6 RADIUS.
2. MATERl.A.L IS DUCTILE IRON ASTM A536 GRADE B0-55-06
3. SEE SEC. 7.05.
4 DRILL THREE 1 INCH HOLES SPACED AT 1200AND 9 1/2"' RADIUS.
DATE
LOCKING MANHOLE
97
REV15"'"
COVER
wr I APPRn I
OWG. 2-022
NO.
~
•• SEE NOIE 2
"
fl6tj
26 3/4-
2!'i 1/4" ,..
~: ~ ~-: ==========~
KIIIG COUr.rY PU'!UC WORKS
KING COUNTY, WASHINGTON
26 l/4•
"'4 1/~
SECTION A-A
LOCKING
98
DATE
NOTES:
11 1,'1S FRO~ CflflFR
.•
'
fillll=DDWN _Jl.EIAIL
'" ' "
--:! ;,
1. MATERIAL IS CAST IRON ASTh1 A4S CLASS 30.
2. DRILL AND TAP THREE s;e· -1 l NC HOLES THROUGH
FRAME AT 120" NJD 11 1 / 16. RADIUS.
3. SEE SEC. 7.05.
REVISION BY I APPR'D I
MANHOLE FRAME DWG. 2-023
NO.
0 ~~~LNEy G/ _
01/ER EXCAVATE TO
ACCOMMODATE ROCK
£=St. f,·-d'
•w.
ROCK-LINED SHOULDER DITCH
JN Fill.~
n~ ,.,
NOTES
DITCH IS LOCATED
AT TOE OF FILL
DEt:PER RCCK FIL~ MAY BE SPECIFIED
;i Sff SFC i'.02
_fJ'-o"
rlJRBFP $HOU! PER
4'-0" ~·-o-4'-(f ,·-.e-__ l ~-~," I
~
ovrn EXC,W,\T[ TO
ACCOMMODATE l'IOC:K
ROCK LINED SHOULDER DITCH
IN CUT SECTION
KN) COLlmY PUBLIC WOPl<S
KING COUNTY, WASHINGTON
!
oi _____ J
TURNPIKE Sf-:OULDER
DATE REVISION
ROCK-LINED SHOULDER DITCHES &
OR TURNPIKE SHOULDERS
99
BY~
CURBED DWG. 2-024
NO.
ROUND SOLID COVER
Mo\RK.£0 •oRAIH" Wrt1-l
LOC!<:IHG 80\..TS. SEE
[1111(; "!OS 2-022 a
2-02.3
NO~S
l'IF'F Sl.::'.t:.S AND SLOPES PER PlA\JS
2 OlJTl.ET CA.PAC TY 0()1 L[SS I HAI\! COMBI\IED INLETS
OVERFLOW E1.£V TO P1!CVl0t
D[1ENTION a, OL SCP.1/tAflON
N:R PUNS
Ji~-
~~ . . W E & t.A00£fl 00
STEPS Ol'FSE'T. SEE
NOTE t. F'ltl.WE &
ro.t:fl: El[V PER PUN
J EXCLPl AS SHO'v'l'N CR NOTED, lJ/\'ITS SH/\Lc_ BE cm~s-RUCTED
IN ACCOHIJ/\N(:L vvm1 ->--JE R::OUIREMEt\TS I-(}~ Ct,TCII BAS,N
TYR:: 2, ~4' IJIIN OlA.M.
4 PIPE SUF'POl~IS 1\NlJ RESTRICTOR/SEPARATOR SH1\LL LlE a=
S,1*,E MA.TERAL. AND BE 1'\J\CI ICRl::D .t..T 3' \VO: sr..:..c1r\JC:;
RY S{f!' DIAM STAlNL£5S ,rm FXP<\SSION BO_TS CR EM:-lf--' )[}ED [ I\J '·NA.:..L SEE NOTf \0.
P!PE SVPPORT{S) 5 X 080"
LN\ft:RT (LEVA.To-I PC:R f>\.AN
R£Sffl!CTOR Pl,f.,'ft WTTH ORIFICE
AS SPECIFIED r,.()T NfEOEO ~
ONLY FOR OIi. POlLU'tKIN CONTROi..
1·-cr .. ,.
... -.. . ..
~-MIN.
j
~ ..
l
!
CATCH BASIN TYPE 2
DIN4. AS R[OI.M£O
SEE DWG 00 2-00~-
RC"40VA8LE WAlV:-
""'1 """""'
Pl.ATE Wl1H ORIFICE
A.S SPECIFIED
J{J
~
El BQ\Ai 1~,nt:.11
KNCl COlMY PUlUC WOAKS
KING COUNTY. WASHINGTON
' .....
STEPS a. LADO£R:
SEE DWG NO 2-006
CLtN+Q(.rr CATE: Sr,t).P
GA.TE. SEE DwG. NO
2-026
l~ El.t'J. PCR PVJ,I
5 11---E RESTRlCTOR/SEPARATOR SI 1.41...L 2E fABRICTEO l-l~Dr-,1
060. ALUMit\L:rvf 2R .064. tL.lrv11NIZED STEEL. ffi 064•
c;1'\L..\i/\NIZED s-EE_ Pl:)E. IN ACCOPD,\NCL '.',1TII AI\SHTO
I/ :C.fi M "!:-i6 M 197 .t\J\L M 274 GA.I 1/ANl?I D STIU
S.-!.A.11 HArV ·nEATIVIENT 1
5 {)lf'."':..ET SI-ALL BE CONM-Clt] :'"J CJ'--\/E:;:T CR SEv\ffi F'IPf-:
'i',TTH 1\ ST/>J\D/\J-ID COUP_ N3 BANJ Fffi CORRUC3ATED METAL
t':F'I-_ rn GROJTEO NTO TI--JE BEL~ OF COt-.J(J~[TE PIPE
7. I r1r: VERTICAL FtlstR STEU OF TI-if-A[STICTOR/SEPARATOR
SH.All BE THE SAME 0~. J.S THE HORIZOl\'IAL OUllET
PIPE. WITH AN 15' MIN DIAM.
8. FRAME MJI} LADDER OR STEPS OFFSET ?D "H1\l
A CLtANOlJT CATE IS VISIBLE F:;:OM TCf'
9
111
B. CLIMB D'.J'/\IN SPACE IS CLE.AF~ OF l~IS[R ,\ND
ClEANOUT CA rt .
C r;'RAME IS CLEAR Cf" CURB
IF METAL OUTLET PIPE CONNl::CTS -o CEMENT COf\.CRETE
Pll-'t OlJTLET PIPE TO I-AVE SMOOTH OD EOUAL. TO
CONCRETE PIPE I.D LESS 1 / 4•.
MUL71-0R'FICE ELBOV'JS MAY BF l_DCA!ED M3 Sh()\,\N ffi
AL_ O:\J ONE SIOE OI-K srn TO ASSURE l.ArJDER
CLEA~CE ,,,,,{-:~----: '. ~-
/ l .,, \
~--J4~--~:7~"::J. '\; A-~-,,,,_ __ ~ : / '"Jn:: : ~
If 11 1111 I I
: \ •:11:: i /
i ", -~~'"" ' 'L '~--' ' 'I!: v~;-,i). v-. ..,
\ \I "\ :'if.: I \ \.,, ~ /~. ',,~"
£l.8!'L
DAT[ IIEVJ$IOfl lovl....-.1
FLOW RESTRICTOR /
CONTROL DEVICE, TEE
OIL POLLUTION
TYPE (FROP-T
DWG. 2-025
NO.
100
SIX MN LY SPICED HOLES
ON 10 J/fi' BOLT CIRCLE
FOR 90LTING TO fl.NtGE
CONNECTION
c=i.
!v\NO!..E WITH
LOCK PIN.
~UST"8L£ LOCK
HOOK 1'.m-1 LOCK SCRBN
/ / \/All\ABLE LENGTH Y 1· ROil OR TUBING.
. -~---'~~
NOTES
0
, , , ,
' ' '
,,/",,.
;
'·,,\ \0
' ' ' ' ' ' ' I
' '
lMLUHE , ,
' ' ' ' ' '•,
' ,
;
,/ IO
; , "' ,,, ,',,. .... ----.,.--(",,."r ,,___ ,-' V / 0
0
.Efillli!
LIO HANDLE
~ ;
0
L cl<NDLE SK>LL BE
ATI,>l:HEO PER W\NUF>-CTURER'S
RECO~~ENOATIONS
SHEAR GATE SIIALL BE ALUMINUM /\LLOY PER ASTM R-26-ZG-.no 0~ CAST IROI\
ASTM A4B Cl.ASS JIIR /\S Rl::.OUll~ED
2. GArE SH/\LL tH-8~ DIN,t UNLESS OT"'!ER'NISE SPECl::IED.
J_ GATE SHALi.. BE JOINED TO TEE SECrON BY BOLTING (THROUGH FLANGE} WELDI\G
OR OTHl::I~ StC.mF II/FANS
4. LIFT ROD. AS SPECIFIED BY MFR WITH HA\'OL[ EXTENDING TO WITHIN CJNE FOOT
OF COVER AND ADJUSTABLE HOOK LOCK FASTENED TO FRAME OR UPPER HANDHOLD
5 GATE SHAL_ NOT OP:':N BEYOND THE CLEAR OPEI\ING SY LIMITED HINGE \IOVEMENT
STOP TAB OR SOM:: OTHER CE•JICE
6. NEOPRENE RUBBER GASKET REQUIRED BETWEEN RISER MOUNTING U>.\GE AND GAE FLPsNGE
7. MATING SJRFACES OF LID AND BODY TO BE MACl--.l~JED F-OR ;:,HOPf:.I~ f-11
8. F:_ANGE MOUNTING BOL IS SHALL BE J/8" OIAM. Sl AINI c SS SI H-1
9 .ALTERNATE CLEANOUl/SHEAR GATES TO THE OEStGN SHOWN A.~E ACCEPTABLE
0 ROVIDED THEY MEET THE MATERl/'1L SPEC..FIC/\":-IONS A30\/E AND HAVE A SIX
30L T : C, 3/ff' BOL-;-CIRCLE FOR SOL TING TO THE FLANGE CONNECTION
~ KING COUNTY PUBUC WOOKS
KING COUNTY. WASHINGTON FROP-T
101
=
DATE
SHEAR
,,,,---,-, ~.---,,
/ ----'-'-;_ --,,
,,.,,.-9 ---... , '
0
Rt\llSIOH
GATE DETAIL
--------,,,_ ,-'
SEE 1'CTE 5
0
MAXIMUM O;:,E\111\G
OF GA-::::
BY I APPR'D
DWG. 2-026
NO.
R0VHD WAHHCU.: CCWER
MAR!([D ·o,wtr 'll'!IW
LOCKINC aoll'S.
~L ~ .'. :.· .; ,'·',11 ,. ' r /j,-..-..f1
ll II
ROUNO IWIHOlf 00\ltR
WARKtD ·oRAH" MrH
LCOONC BOLTS.
Ii _)~
I . ·-1 ! -l 1· • ,;1, • -i....n "" I.
1
."1.
NOTES:
1. PIPE SlZE. SLOPES ANO All ELEVATIONS: PER PLANS.
2.
3.
OlITL[T CAPACITY: NOT LESS THAN COMBINED INLETS.
CATCH BASIN: TYPE 2, TO BE CONSTRUCTED IN ACCORDANCE
WHH DWG. NO. 2-005 AND MSHTO 1.1199 UNLESS OTHERWiSE
SPECIFIED.
•. I I•==,/\
11 II
1~==~l S([ [lS()II [)[T ..... ~ •• COVERS: ROUND. SOLID UARl<EO ·oRAJN,· WITH LOCKING BOLTS
SEE OWG. NO. 2-022 5c 2-023.
" " :F==~l
II II
:~==~: (.u._ I~.-rLOW 011mcrs
II U/1~J/ Jf=='il/
ll !I
11::::=M
II II\
~ I l~::~f \",
II 11 ~
If II . ,, 11"===-1
· II II .. l~u~:
11 II
:F"'=~l
11 II
:F==~:
II ll 1r=·~:
II ,r
" -'
! Pt: Ntl l
SECTION A A
l_
,.
..
.....,, ..... ,
""TDmGHT
''""''""
ELEVATION
HBOW DEJA1L
(f) KINCl COUNJY PUii.JC WOll<S
KING COUNTY, WASHINGTON
•
•
'·
' .
SECTION B-B
-
OAT>:
5.
6.
7,
8.
9.
OR!rlCES: SIZEO AND LOCATED AS REQUIRED. WJTH LOWEST
ORIFICE MIN. 2" FROM BASf
8Af'HE WALL SHALL HAVE f4 BAR Al 12'" SPACING EACH WAY.
PRECAST 8AFFlE WALL Sl--W..L BE KEYED AND GROUTED IN PL.AC£.
BOTTOI.A ORIFICE Pl.ATE TO St 1/4. MIN. GAlVANIZED STEEL
AND ATTACHED WTTH t /1" STAJNLESS STEEL BOLTS. OMIT
ORIFICE PLAT£ IF ONLY FOR O!L SEPARATION
UPPER fLOW ORIFICE SH.6J..L BE ALUMINUM • .AJ..UMINIZED STEEL
OR GALVANIZED STEEL SEE OWG. NO. 2-025. GALVANIZED
STEEL SHAU HAVE TRE..ATM:tNT l.
A
-
' ' ~--
m
A
.El.ML
m
1.,1.-.1
FLOW RESTRICTOR / OIL POLLUTION
CONTROL DEVICE, BAF'FLE TYPE (FROP-8 DWG. 2-027
NO.
102
~[
UPP[R 8,ANO
...
!:l
3/' W,M. SMOOlli ROUND BARS
EQIJ.lil.lY SPACED. BARS SfW.L 9C
WEI.DED TO UPflCR Ii: LOWER ~DS.
fil,tj
£
>!<" , ....
5MOOn, ROWO
BAAS £01.W.LY
SPACED (4'" 0.C
-.)
~NOT[, 8ARS
OMITTED OH
OAAw,,.;
; *'-.. ,;l'L..... L....,..I r _ ___.,,
LOWER e,,.,,()
WR H/>,-HOl£S E ) ,-___.!")
OW,I_ _ __ SPM:EO OI.W..LY [ I -
(i) KJNQ COUNTY PUBLIC WOA(S
KING COUNTY, WASHINGTON
flfYATtON
C8 INNER OW,,.
<8: ... ... ...
"' ,,. ,,. ...
"' 114·
NOTES: ,.
,.
DAT[
DEBRIS
103
{
UPPER BAND
J/4'" DIAM-BAA
t/t" Pl.AT[
J l1r
J/4' SAA
DRILL HOU:S
FOR LOCK
'!_
\ \ ___:j I I -,
~r--Lf::l lo :,
L_~]
LO'l'tER eAHt> --
J L!!,.
ENTBX CATE DETAJL
All. STEEL IN PL.ATES, BARS ANO BA.NOS SHALL CONF"OR'-4 TO THE
REQUIREMENTS OF" ASTM A36.
DEBRIS CAGE SHALL BE HOT-DIP GALYANIZ£0 IN ACCORDANCE
WITH ASTM A12.3 (AASHTO M111).
IICVISION
CAGE
BY I AJ>PR'D I
DWG. 2-028
NO.
2 H ... ::.: =~ /,
/\ \
~
l/,4." "1/' GROOV~ --\--_:,
[XP/l<NS10N JOII-IT
·~
OU~I-IY JOINT ·---t-____ "./ j
1/4" Y CfiOOvE -t---(
A
BQLl ED CURB & SIDEWALK
I
' I
_J
==I
'(',, \:';i:,;.;,;s-z~:r,""'"~t1 ;);} ;:'·J;;-4t·;;.:;;: .. ;: :;;, ·;;]· f> ~
~ 'nPANSION JOINT
" »
7 "'//~%%%Mt;gq
SECTION A-A
NOTE:
SEE SEC. 3.04 FOR JOINT REQUIREMENTS.
2. FOR INTEGRAL POUR CONSTUCTION, 1/4" EDGED GROOVE MAY
REPlACE EXPANSION JOINT AT INTERfACE BETWEEN CURB AND
ADJACENT SIDEWALK
KI\Kl COUNTY PUBUC WORKS
KING COUNTY, WASHINGTON
A
_J
i ? ~ ~ Li
'"' '; ', l >-=--DllM~Y JOINT 7 l _ ~ L ,
71 I I I \
PLANTING STRIP
I
1/4" "\/' GllOO'/! _/
fKP,i,NSIQN JeiNT -f--...(_------.J
----DUMMY JOIN\
0 M.lvt 15' C----C
E.XPAN510N JOINT
ALOl\'G CURB
1/4° "V' GR00\1£
0 ~-3 C-C
QUl,j-"Y JOJ.~T
B
YERDCAI CURB & SIDEWAl K
'~·0h~ h:::~J~i~
SECTION 8 B
DATE llEYISIO'i -}iT~J
CURB & SIDEWALK JOINTS
104
s: % 00
B
DWG. 3-001
NO.
NOTES:
~ ~
WIN.
•TOP ~ uP AT ~"I'S
-v~~
t1
EXTRUDED ASPHALT OR CEMENT
CONCR£TE CURB 3.s
{"""'
t(f' :3 l/'l" ~ EKPAASKJN J()Nt
'.-r---:V,__,_~~O-~/n i::r--: -... ~' ]l
~L_ · ·· l" · , · · ·. / ~I
1
,,. , .· ; ... ·.~-.. · ,cr ~oo .. c.,n
,--er I \_ • Ol'TIOK'J. fOR
'"""'""-"""
CEMENT CQNCRETF BOU FD Cl IRA
1. SEE SEC. 3.04 K.C.R.S. FOR JOINT REQUIREMENTS.
2. ROLL GUTTER TO MATCH POSITM SUPERELEVATION.
J. SEE DRAWING NO. 1-006 FOR CONFIGURATION OF
FIU & W~A.Y BEHIND CURB IF REQUIRED.
4.
5
(i)
FOR LNiEGRAL POUR CONSTRUCTION. 1/4 .. EDGED GROOM l\o\AY
REPLACE EXPANSION JOINT AT INTERFACE BET'WEEN THE CURB
AND AO..IACCNT SIDEWALK.
SEE SEC. 3.03 FOR EXTRUD£0 CURB ANCHORAGE
KNQ COLM'Y Pl.El.JC WORKS
KNG COUNTY, WASHINGTON
DATE
CURB
105
i
II ~4
1~ I
i; "I .!. , -r~
• •TO CONF"ClAW TQ ~
SLOPE OA 0.02 n.;n.
-O.O;.> FT./n.*•
MOlJNTABI E CEMENT CONCBEIE: CJ !BB
,......... JOWi
,, ----' ~~ nLn. J 'II ,3 C f·''•. J -.' ~· ·.-.. :· ,. . . .. · ..... '° •. .I· •• _-<: ....... ,._-.
I ·-~
• MOTE: TOP 0( UP AT tlRl't'tWAYS.
CEMENT CONCBUE Cl JRB & GlITTER
"""''°" BY ' Affit'D I
DETAILS I DJt..G, 3 -002
NCTES
t:iX.'c. tt SliO'Jl{)(R
tOGt or PA'-1:W(MT
COl,OAERCIAL/INDUSTRW. DRM'NA YS \A/l[)[R 1~ JS' u;v
BE APPROVED BY TI-,E EI\GINEER CONSIOER!·\IG l30TH TRAFF:C
SAFETY AND THE ACTMTY 3EING SER\ltO. 1\LL COMMl:CR.Cl.4Li
INOUSTRIAL DR.f,JVI/AYS SHA_L HAVE AN EXPANS.ON JO.!NT
LOCATED MID-\NIDTH SEE SEC. 3 04
2 PIPE SHAU BE
3.
,.
5
A SIZED TO CO\/VEY COMPUTED STORM W1\TCR RUNOFF. AND
B MIN 1 °Z' OlAM., /\ND
C EQUAL m OR LARGER :HA\I tX-STING PIPES INITHIN 5:)C,'
UPSTREAM
EXPOSED PIPE ENDS SH!'\L.L l:lt 8EVE:LE'.O TO W.TCH Tf-£
SLOPE tACE ANJ pq_QJECT NO MORE THAN t' BEYOND S: OPE
SURFACE PROJECllNG HEADWALLS ARE N07" ACCEPTABLE.
CONCRcTE PIPE SHALL HA"JE MIN COVER or ff' TO
FINISf.' GRADE .AL OTHE:R TYPES CF PIPE SI-ALL HA'J1
MIN. 12" CO\l'ER
RIGHT-Of"-WAT LIN!:
-
~ ! ~·,:·'" ~1 •;:: WI ~1
OBM'Mt 'WJPJH
RESJOEHlllJ..
10'-Cf' MN
20"-0"' MAX
COMM /!NOUS1R
3l=~ = 1
~ I ~i 3' i,
a: a1 i' i -""'-~ PIPE SHALL BE INSTALL:'D IN A STRAIGHT UNIFOR\1 ALIGI\MENT
AT A MIN. 0.5~--SLOPE (0.5 F"T PtR 100 n.) \IITTH THE
DOV\INS1REM/. END L01~,1ER THAN THI-: 1..PSTRCAM EN=i ~02 n:./n. gl .,·::.'.--~~t': ~i,.._ . ' . : ·~~ 21~+::-6
7
PIPr~ MAY Rf.: OMITTED IF ROADSIDE DITCH DOES NOT EXIST
AND QRNEWAY DOES NOT BLOCK NAT JRAL FLOVIJ
DRNEWAY SLOPE ShALL MATCH TO B.~.CK EDGE OF tiHOJWLI~
/:lU I SHOUL Dl::.R SLCPE .A.t...D :'D3E OF srOULDER SHALL NCJr
BE A~TERED AS A RFSu .. ·1 OF DRl'vt:WAY CONSTRUCTION
8. PAVED OR\,1WAYS SHAl. Ht PA\!ED T>-JROUGH RIGW-OF-1.NAv
WITH .A. C OR B ST. RUT NOT P C.C
9 GRAVEL DRIVEWAYS SH/\LL GE PAVED BET'NEEN THE EJGE Cf"
PAVEMEN-:-ANJ R/W WITH AC. CR B.ST Cl\, Y 'NIIH LJIMlNS!O/\S L•W.
10 SEE SEC. J.01 AND 4.81
(i) l(NQ COLfflY PIJl3UC WOlt(S
KIHG COUHTY, WASHIHGTOH SHOULDER &
106
. . .. ' J.. ,.., ~ ,•.:;; ,·, .. -.... f-.'.·' ',1.1---~·-'-'"---.~ -
SECTIOtf t,-A
DITCH SECTION
....... ., /. . ~
--cl o~,.,, ~· ··.·."':"-' .. -. --/ .. ·~: ,~, .· ., ·.;_•'
DRIVEWAY DWG. 3-003
NO.
(I)
Rt:Sooom•1.
10'-0" lllN-
20'-0" UA>I.
COWW~WSlR.
2$"-o"' MK
~·-0" 1,1,U_
s·-a·
r-RICHT-OF-~Y \J'iC
'
M,,\lCH E•ISTNi -y""""
COliENT CONCRtTE OR!VtWAY :i• THICK
SECTION A-A
KNl COUNTY PUBLIC WOAl(S
i<\N(; COUNTY. WASHINGTON
CURB &
~I!
GUTIER
107
NOTES:
1, COMMERCIAL/INDUS1"RIAI.. DRrvEWAYS WIDE~ THAN 35' MAY
BE APPROVED BY THE ENGINEER CONSIDERING TRAFFIC
SAFETY AND NEEDS OF THE ACTMiY SERVED. AU.
COMMERCIAI../INOUSTRIAJ. DRIVEWAYS SHALL HAM ,trN
EXPANSION JOINT LOCA1ED MID-WIDTH. SEE SEC. 3.04.
2. SEE SEC 3.01.
J. SEE SEC. 4.01 FOR SURFACING REQUIREMENTS.
'"""°" BY I Af'fll'D i
SECTION DRIVEWAY DWG. 3-004
NO.
Ci)
.... : . : . : . ::-:~
"''""""' 10'-o" MIN.
20'-ff' MAX.
COIAl./~DUSTR.
:Z-~'-0" WIN.
3$'-o" WAX.
Ca«NT CONCROl:
ORNE'IIIAY ~ THICk
MliICH ~
"""'''" """"
SECTION A A
KtfO OOI..NTY PlB.JC VIOl'KS
KING COUNTY, WASHINGTON
..... -...... -. . . . . . . ............._ . . . . . . . . ........ ······~
REVERSE
108
DATE
1>U,NTHc; SlRIP. r JNr
NOTES:
t. A REVERSE SLOPE DRIVEWAY rs SUBJECT TO APPROVAl B'I'
ENGINEER CONS1D£R1NG NEED f"OR AND COMPATIBtUTY
OF Tt-llS VEATURt.
2. COMt.tERCIAJ./INDUSTFUAL ORIVEWA'fS W!OER THAN ~· MAY
BE APPROVE() CONSIDERING l!W'F'"IC SArCTY AND NEEDS OF
THE ACTMT'I' SERVED. All COMMERCIAL/INDUSlRtAL
ORIVEWAYS SHALL HAVE AN EXPANSION JOINT LOCAT!O
MIO-WIDTH. SEE SEC. J.O.&
J. A STORM S[W[R INLET SHALL BE LOCATED WITHIN 20" BUT
NO CLOSER lHAN 1 O' UPGRADE FROM NEAREST EDGE Of
CURB TAPER.
4. SEE SEC. J.01.
5. SEE SEC. 4.01 FOR SURFACING REQUIREMENTS. -lorl....-ol
SLOPE DRIVEWAY DWG. 3-005
NO.
ST,t,t,ID,411() CUFl8 RACMUS -----.----,
I
~
R•FF,C S,G""-
'>IANOAAO
I ~
. ,,,. """""" MIN, C0ir.Oil[f«:W.
" """SlRW.
' v-PROP[lm' UN(
I -, --+--I-----
I
1
SIOEWA,lJ,:
PI.AAllNG :slAIP I I
CURB
·~
NOTES·
NO PORTION 01-,'INY DRIVEWAY SHALL ENCROACH IN CURB R~lUf{N
2. COMMERClAl/lNDUSTRIAL DRNEI/VAYS '.'AUST BE APPROVED BY -:-HE
ENGINEER. CONSIDERING BOTH ll{/11-1-IC SAFETY AND T"1E ACTMM
BEING SERVED AL l. COMMERCIAL/INDUSTRIAL ORMWAY$ SHALL
1-!A.VE PN EXPANSION JOINT LOCATED MIO-VVIDTH SEE SEC 3 ll4
3 FOR R0/1fNVAY CLEARA\!CE OF UTILITY POLES AND STRUCTIJRES
SEE SEC 8.02G AND D.'\G NO. 5-001.
4 DRIVEWAYS SHALL BE LOCATED A.S f'AR ;:~or/ THE INTERSECT:ON
AS POSSIBLE
"""'"" TAHR AND Fl.ARE
UI" MIN
6ElW£EN ORIV(WA'l'S
S[rt.'!NG SAME PARCEL
~ ""'
MTE
.,,,.....,.-R!Gtfl-OF-WAY l(N[
~--·1-
O(PRESSEO cu••7
ORfVF.WAY WIDTH
10' "'N 20' t.lAX
COM.i[RCIAL/
INDVSfR. 2~' MIN
J~' M,U. [XC(PT
ONE-WAY 20" MIN.
IIEVISIOI\I
1:_~_I!!
;y
FIRE Hl'l)RANT
VTIUTY POU.
SE£. NOTE 3.
l
I
~· ~!~
APPR'D l
~ KNJ COUNTY PUllUC WORKS
KING COUNTY, WASHINGTON LOCATION & WIDTH OF NEW DRIVEWAYS
109
DWG. 3-006
NO.
,------1----·--i
i ~~-I . I
i Y· ! PROPERT'!" LINE i I . ' ----1 r -----.c.:::. -----i j l ~ JOINT USE DRIVEWAY TRJ.CT
i I
EXISTING DRIVEWJI.Y~ ~ EXISTING ORMWAY
-_LL J l ~-R,GH,QMAY UN[
~
---------~ (D<i; ~r PAVEUENT
NOTE:
~----
-··
--------SIDEWAI.I<
1 SEE SEC. 3.01 FOR TRACT W!DTH AND PAVING REQUIREMENTS.
-----------T------------
1
~ -------+Y / ------PR<>PERN UN[
JOINT USE Dll'IVEWM TRACT I
------PAW AAU. TO fllGHl-Of"-WAY
-------WITH to· RADn.JS RflURNS ----.. ----I -----~ RIG~-OF-WAY LIN[
-------~ [DC( or SHOULDER
-------. _/L -~ EOG[ OF PA\/E'.W~---------
5i3
---+----
.lll!&l.
R£VlSl0H I BY \ APPR'O I
KtlG cotMY Pl.&JC WORKS
KING COUNTY, WASHINGTON JOINT USE DRIVEWAY TRACT OWG. 3-007
NO.
110
(i)
~-1
VARIES
-LLh_d
'I I r-
RAMP LOCATIONS
ON REYOENTW ACCESS STREETS
I _j "VM\t~
~~
I I
KING C(XJNTY PUBLIC WOfU<S
KING COUNTY, WASHINGTON
~ ~
_i
~---
( (
t-J l l +r====-~~----------
""'"
NOTES
I
I
I
I
RAMP I OCATlONS
ON AATERl>J.$ AND COMM~RCIAL
ACCESS STREETS
~
__}-I •
L CATCH BASIN AND INLETS SHALL BE OUTSIDE TH( CURB RAMP
(24'' MIN. CLEARANCE FROM AAMP). SEE SEC. 7.05 FOR
CROSSWALK RESrnlCTIONS.
2. CARE SHALL BE TAKEN TO KEEP THE RAMP FROM CONFLICTING WITH
HYDRANTS, POLES, INLETS, AND OTHER UTIUTIES
J CONSTRUCT RAMP lN ACCORDANCE WITH DWG. NO. 4-002 OR DWG
NO. 4-0DJ.
4. CROSSWALKS AR[ NOT ALWAYS MARKED
5. WHEN RAMPS ARE CONSTRUCTED ON ONE SIDE OF STR£ET, RAMPS
SHALL BE CONSTRL!CTEO AT CORRESPONDING LOCATIONS ON
OPPOSITE. SIDE OF S1REET.
DATE REVISION BY I APPR'O
CURB RAMP LOCATIONS
J ~
DWG. 4-001
NO.
NOTES
~ .. . .. . -. . .. . .. . . . . . . . ····--······ PI.ANTIHC STRIP .. • • • • • • • <• "") ••.••.••• .. . . . . . . . . . . --. .. .. . . . . . .. . --. -
l
I
@
RAUP AND AFH-<!:JACHES SHALL BE C...EAR Cf" OBSTACI ES
INCL HYDRANTS, POLES. AND INL::TS.
2 RAMP S~l BE TE(;"lJREC BY ltvF'RINT CF META._ GRID
WITH 1 /'Z" SPAClt\'C
.3, RAM? CENTER LINE SHALL BE PERPENDICULAR TD ffi
RA.DlAJ... TO CURB RETURNS ,JNLESS OTHERV\':S:': APPROVED
BY ENGINEER
4 VVHEN RA.MPS /IRE CONSTRUC:ED ON ONE SIDE Cf" TH[
S:HEcl RAMPS SH.AL~ B::. CONSRJC1Fl1 AT CORRLSf--'ONOl,\JG
SIDEWALK LOCA TlCNS O\J OPPOSrfE SlrJF OF STREET
SEE D/IG NO 4-001.
5. ON AA1£RlAL S rRcf:. f::i. IN C;ENERAL ~ CURB ~:\MPS
SHALL BE CONSTRUCITD -.,,NJ =>ER Rl>D!US. IN CR
PREFER/\81 Y !\[)J/\CEl\11 10 11 JE MAIN PEDESTRIAN ~AThS
6 ON RESIDENTIAL STREETS m WE RC U l"ILITIES ARE I~ CONF'UC't
CR STREET GR/DE E.X:CEEDS 4.0X CURB RAMPS MAY BE
CONSTRUCTED ONC PER RADIUS. AT MIJPOINT OF CURB
RETl.RN OR. AT lr.WN Pl:.DESTRlfaJ.J PA1H
7. SlE SEC. 3.02 A.ND 3.05.
Ci) KNCl cot.MY PUIIUC WOA<8
KING COU 01. WASHINGTON
<' 3' a: I
• L ...... "'"""''
1? ~.
~
CURB RAMPS IN
112
@
\
\
. . . . . . . . . . . . . . . . " . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . -. -
12: \ 1:i;;x. SlOf't
3·-6"
I~
1:.=S[ = ~-
o.oi n.;n.
"' < THICI< CCU(NJ CCt-lCl!£Tt SCOtAllC
SECTION A A
VERTICAL CURB· NO. 4-002
'r
~
i
@
NOTES
~
1. RAMP ANJ .t..PPRO/\CHES SHALL BE CLCAA OF OBSTACLES
INCL HYDRAI\ TS. POLES. AND INLETS
2 RAMP SHALL BE TEXTURED BY IMPRINT OF l'v\ETAl CRID
WTTH 1 /t" SPACING
3. RAMP CENTER LIUE SHALL BE PERPENDICULAR TO c.R
RADLAL 10 CURB RETURNS UNLESS O!HFRWlff APPROVED
BY ENGINEER
4 \l\t,EN RAMPS .ARE CONSTRUCTED ON ONE SIDE OF THE
STREET RAMPS SHAL'_ BE CONSTRUCTED AT CORRESPONO:r-,,,G
SIDEVVALK LOCATIONS ON OPPOSITE SIDE OF STREE~.
SEE tlWG. NO. 4-001
5. SEE SEC 3.05
KNCi COi.tin' PlBJC WOA<S
Klt-lG COUNTY, WASHINGTON
1'_~(,f'
~
* L ...... ""'""'
~
I l~ •
I
~;~ \
CURB RAMPS IN
113
~\
@
--[
12:t IU.)i'.. SI.OP
illI!Qlj A-A
ROLLED CURB DWG. 4-003
NO,
~
11 'SI'
' 4!:,,._.,.,\.,/..
• ..:.e.9-~ .,,s)
,1 r::.,r:Jf"/ ,,.,.
f.k-.).'i-'°''.-i~~~ t..:
·~
SFCJION A A
KNG COLtlTY PU8L1C WORKS
KINC COUNTY, WASl,INGTON
~i
loU.TCt< [:tlSTING ffi
~O SlMAC[
ASPHAl..f CONCRETl:
NO-:-::S
.,
fj... ').~ ..._ s·i.r.f<~,ot ':;/.',-<J..,y,. .,,,.,. ,.A 'ijft'-if-•
'-l~t~ -.;'fl'
i,IY\.~ -,.o
1, Frn 1/VIDll lS OF SIDE\/1/ALK SEE SEC 3 02
2 FOR \11/IDTHS DF Pi\\/FMF'..fT N~O ::i"lUULULh; Sl±: s:.:cs 2 02 2JY3 ,'IJ\0 2 04
J. ShOUl_[EJ~ ~;-tr,u tll ~il.HJ N:U) /I'S l.:ZL()IJIRED 5Y SECTIOt~S 3.C7 AND 4.C,
IF PAVLO SliDIJLO[R 5LC)P[ SHALL MATCH :::::ROhN SLO::,E CR JJ2 n./cT
FOR CURB AND SDEV-1ALK ~IOIN-:-S SEE DNG ND J-001.
5. ll<l,t\Slll'..JN 1---1/1.:\F-' SHi'.>U [l[ T::::XTI~R[J o,· /v1FRl~T OF r•,1ETA.. G~ID WITH
, Ii" sr.t..CNG
CEMENT CONCRETE SIDEWALK
TRANSITION TO ASPHALT SHOULDER DWG. 4-004
NO.
I 14
A:ltHT-OF-WAY UM£~ -------RIGW---OF-Y'JY LIN[~~
/
~
<e>
~
_,_,
----------=--• NOT> LOC -----. OK ~
OlA(C110N
"' """'' -
O\JTSIDE OF CIJBVF
POSTED 40 MPH & OVE ~
LOC L.£'>·'.o!..: Of-CURvt ,FEET) A-: EOGE Cf-
~V[LED 'N/N H-lD\1 ~.C Vi p,
SOFI: S>!rtr C',t~· ,.FEIT) 8[YOND P."
~ PROHertCD POL[ LCICAOON (F'CET)
(LOC + 'SOff) W:CRE P0l£S U-1
OEISTACLES. ~vs, ElE ROICM:D 00
B,IJl:fllCAtl[D
~. (,un OH OUTS()( a:: CVfMS wrTH
~ Sf1E£0 LIMIT OF' +o MPH 4 (MR
40 -..
,0
"
LOC • 220 (SOR)
LOC + 2~~
L::C + .!DO
LOC t 3;::;;
TC RO,l,[IWAY ,_-i-, SHOULDE::R CR
~ABLE. CLJc(B ON OlJTSID[ or ·:::UM ,,., '"t
-RADIUS LESS THAN ~·.
-M't.o ~....E..:.' GRf'.li.TfR ll"W,I
OR E~'JAL Kl 40 MPII
~ -~ ,..,. EOCE or TP,.\V{l[O WAY ~ ~--~ /
/_/ ,/--:cj~
v_/,/~
NOTFS
GENERAi CASE
P/X· r~.Jl~LE
~i.k_~;J .~H SHOULOCR
1 T.IIHGE~. ffi
2 INSU '~ CiJR'>t. m
3. Ol.!1:;;!ot CF CL Iv' ErTHER rt"
-POSTED S"EED LESS THM1 4::, ..,:,,...
-IWllUS CRtATER lKA.', ~!-X' C,,, ~WA'!'
t,€[1'1NC ,i.;,.I. CURRCNT l)[Sl(;N $T.l.,'/Q..I..CCr5_
TJ-E STANDARDS SHALL APPLY 10 r\! R Y r-.EJV
PLACEMENT .t>ND E\tERY PLANNED. N0\1-EMERGENCY
REPLACEMENT CF EXJST1NG POLES AND OTHER
UTILITY STRUCTURES WITHIN KING COJr-,.,rrf
RIGHT ....OF-..J.i'VAY
2. NO POLES \IIAY BE REPLACED 00 THE 01..ffSIDE
a= A CURVE WITH A POSTED SPEED LIIAIT Cf 40
MPH CR OvER UNLESS .APPR.0\/"""ill THROUGH A
VARIANCE: REQUEST
3 SEE SECS. 5 11 & 8.02G.
KNl COlfflY P\8..IC WORKS
l(ING COUNTY VVASHINGTON
CLEARANCE OF ROADSIDE
ON SHOULDER TYPE
OBSTACLES
ROAD DWG. 5-001
NO.
115
~
'-
! ~ """' """'""''°" '""'-or-... , ""'
I VARIES. ~ _ 20' R[Sl0[N1LAJ.. ---;
30' Nn[AIA!.
' I
l I
' I
I -002 n. 1
I
' I
l I
' I
I I '''"""" '
I r
' I
NOTES:
1 SEE SECS. 2.02. 2.03 OR 2.04 FOR SUPEREU:VAflON REQUIREMENTS.
2. SEE SEC. 2 .1 0 FOR LANDING REQUIREMENTS.
KJ\IO COLMY PUl3UC WORKS
KING COUNTY. WASHINGTON INTERSECTION LANDING
116
tm9· 5-002
(i)
.,
eAARICAO£ NOTG.·
""'
MOTH ot RAIL
t.CMCTH OF IWL
"'""' .,.-c u~ "'''""~
FLEXIBU'IY
l!OLTS: 2 P£R JOIHT 1/t'x ~ L"G $CAP'S
GN.V. ~OR lt'X 1•
~~ .. ,
~
~ 1
!
~: 4•)( ft WIN. Pfl:[S~A[ lREATEO
OR C(~ PAIHlto '1!).lffE .
.FIXED {PERMANENT)
----YPE HI aARRiCACL
S,.i.ND,&l,,:,S, FOR
AOOED STABlLIT'r
,v,..-:-,
MOVABLE (TEMPORARY)
TYPE Ill B1\F~.RICADt
r rr •
5' lr,llt,l. .. w, f:f YW. , ,. ""' ,:r M.U. 12" iu.x.
2' WIH. 2" MIN. 4' WIN.
3' YIN :Y WIN !," WIN
~HEAvt~i '~"' • POSt Oft ..... , S>OOS
[S$EN11AUY PORTABLE ,ssam,,J.LY
MOY-'SLE """""'"'
...
',t'j/;'UI
l(f'IQ COUllY Pl8.IC WOAl(8
l'.ING COUNTY, WASHINGTON
m,; OF
SUP!'ORT
YARl[S
Ii
:!.1 .. A
~ARI~
.. ~
II
---
$
" ' h
·~
T)ff I BAARICAOE
STRIPE NO~ES
ORANGE !: WHIE IF ":"EM::>ORARv
RE: & WHITE IF PERVANENT
REFLECTORIZEO
SlANl DOWNWARD, RIGHT OR LEfT,
IN DIRECTIO\J TRAff"tC wr..1. PASS.
S_ANT BOTH :, RECTIONS FROM MIDDLE
IF ~R,\1,---IC P/1SSES ,POTH tl\OS
WIDTH e· EXCEPT 4 If RAILS i\l~F
LESS TH.A.N j• LOI\G
SLA."(:" DO'l'INVVARC TO Ml):·_E AT END
OF CLOSED ROAD
S:CE SEC. 5 :? f1'\iD MUTCD SEC.6C-8.
117
NOTF
BARRICADES
FOR DIMENSIONS NOT
SHOVVN Stt l ABU:
TYPE ll BARRICADE
DWG. 5-003
NO.
• C~H LINK fUOCt
j
1 't' MJH. THICKNESS Of T-< OIJl,RR'I' SPAUS
GRAVEL BACkfll..l FOR ~HS z
P[RfORATEO
PIPE ~ WIN
nLl£R F'A8RIC
.. ..
;
"
NOTES
@
SEE' SEC 5.01.
2 WSDOT/APWA 9-03.12[4)
J IF ROCKERY OR RE"."Al."Jl,\JG WAU IS BEHIND ROc..LED CURB
OR Dr< A RliRAL Si:GION. FACE OF ROCKERY 0~ RETAINING
'1111ALL MUST BE A MIN. OF 1 o· rnoM TRAVELED '1',)W
4. CHAIN LINK f-tNC::C:. IYl-'t NO. 4 D-{ 6 (WSOOT/APWA s·ANDA.RD}
FLOUIF~[D vVH[N r~OCKErN HLIGHr IS IHKll eC[[T OR (3R[AT[R
KtlQ COtfflY Fl8JC WOfl<8
t(IMG CCJUWY. WASHINGTON
4' -6
1'A'l"ITiiin"
EXCAVAT(IN (»/LY
1,
ROCK FACING,
118
~ALK~
. s
§ ·1~ 11 ~ ~ ~ I •
~-o°Tn.;n. ~-~t1Ll::·.!,~ \' ·D.~:-;-
... -~f~~-~
CUT SECTION CWc,G. 5-004
* AS M[C[SSAR'Y to W((T T[M..iN AND
SICHT OISTANCt RtOUR.MCMTS
VARIES ,;. ·'-<T MIN. ... ,
I i \
8 b i i '
·f~ ~·~ /~
"""""' ""'"""
a ~
·/Y
NOTES
1 . SEE SEC. 5.o·
2. WSDOT/APWA 9-0J.12[4).
3. FlAffiR SLOPE MAY BE REQUIRED IN LESS STABLE SOIL
4 CHAIN LN< FENCE TYPE t-0. 4 (WSDOT/APW.O. STPN~ARD)
OR HANDRAIL REQUIRED VI/HEN ROCKERY HEIGHT IS 3' OR
GR&\TER SEE DNG. NO. 5-006.
cxe;..W,TION Ot,ILY
5. FOR ROCKERY HEIGHTS EXCEED:NG -1'. SEE DII\IC. NO 5-0Ci7.
6. TRAFFIC BN--tRIERS MAY BE REQUHEO C)r,,, ROADS WITH SPEED
LIMITS or 40 MPH OR Gf~ICH \1\/HCl~f: l~OCKl:::l~Y HEIGH~·s
<I>
EXCEED 6 SEE CHAPTER 7 OF THE VVSOOT DESIGN MANUAL
KNQ COlfflY Pl8.IC WOll(8
KING COUNTY, WASHINGTON
...------I.RAvtl BACKAU F"OR ()RAINS 2
~er~
FUER FABRIC
ROCK FACING, FILL SECTION
119
DWG. 5-005 NO.
VAAllS •
1 ';( IUi THICKNESS
1"'-~· OUAAR'r" SPILLS
GftA','[L 84Cf<flll FOR DR.1,;~S
NOTES
1 SEE SEC 5.01
2 WSDOT/APWA 9-03.12(-4]
3. CHAIN LINK FENCE 1YPE NO 4 (WSDOT/APWA STANDAf-m:1 Ck
HANDRAIL REQUIRED \1\iHEr-..· R:JCKERY HEIG-ff 'S 3' OR GREJCFR
4. DP SHALL BE CO\ICREE CLA.SS 3000
5 FLATIER SLOPE MAY BE REQURED 1\1 LESS STA:3LE SOILS
6 FOR ROCKERv HEIGHTS EXCEEDING 11'. SEE DNG r,.,o 5-007
7 TRAFFIC BARRIERS MAY BE REOUIRFrl ON RO.A.OS WITH SPEED
(®)
LIIJITS OF 40 MPH OR GREAfl:.R. ',','HERE f-EIGHTS ::xcEEJ 6
SEE CHAPTER 7 OF' THE WSDOT DES;Gr-.; W-.NU/\.
KNO COlJm' PIJEUC WOAKS
l<iNG COUNTY. WASHINGTON
~T°o-AA1ii~.2
FILTER rA8F!"iC
ROCK
VAA>ES
e·-cr MIN.
~~~NK---......_(
i •
..
='
" -=l==l'·i
'""5 N[C[ss.Afrt' TO YE.ET TERRAIN AND
SIGHT Ols:JNICE R[~REWLfffS_
~ ~~.:
I
n
!
/j
~
i'~ I~
FACING
120
~
PAY UMrtS
CXCAVATL!)N Of-IL Y
UNDER
I
I
~
SIDEWALK
-Gl>OOND
tmf· 5-006
NOTES
i
'? ..
,._,
' ·f
/;
ROCKERY FACINGS ARE TO BE CONSTR.UCTED TO KING COUNTY ROA.D
STANDARDS SEE SEC 5.01 AND O\NGS. NO. ~-OG-L THROUGH 5-0D6
2. THE 'WALL FOUNDATION IS TO BE CLEARED OF ORGANIC 'v1ATIER A~D DEBRIS
AND THE U~DERLYING MINER'4.L SOIL COMPACTED TC 8 5 PERCaH OF T'1~
I.I.AX. DRY DENSITY. THC EMBANKMENT MATERIA_ IS TO BE GR.A.VEL BO~ROW
MEETING THE REQUIREMENTS OF 9-03.1~ OF THE WSDOT STANDARDS THE
BACKFILL 1 S TO BE PLACED IN THIN uns, NOl lXCEEOi\G SIX INCHES IN
THICKNESS AND COMPACTED TO 95 PERCEN-:-OF THE MAX DRY CENSITY
3. GEOSYNTHETIC FABRIC OR GEOGRIO REQU!.~EMENTS ,NCLUDING TY;::,E VERTICAL
SPACING (Z), AND EMBEDMENT (LR) Will BE DETERMINED ON A ROCl<ERY B,
ROCKERY BASiS BY A PROFESSIONAL E!\IGINEEK
4. 2B IS HEl3HT OF FIRST LAYER OF REINFORCEMEW ABOVE COMPACTED
SOBCRADE ELEVATION
5 EMBANKMENTS BEH 1 ND ROCKERIE:S EXCEEDING 4' N HEIGHT SHALL 8'.:
REINFORCED WITH GEOSYNTHETIC FABRIC OR GEOGRID
"'
L8jfR~F O:E~'tn_'r
LW • 3.0' MIN.
~ KNQ OOUNTY PIB.JC WOll<S
KING COUNTY. WASHINGTON ROCK FACING, FILL SECTION
121
REINFORCEMENT
N
N
N
N
""! -, !t
DWG.
NO. 5-007
~
\,'
lo
JOM·
JOM
,.L
··-<f
MIN. o.;..DfNG
""'"'-~DRJ.IL
}~J.9_ 4' :S" T.Q.__£
,-----1-,
' ,--
' -t--
' .l__
-,-
' -+-
' -+-
' _.l_
CONCRE~E STEPS
~
4'-0"
MIN """viot-lG
A
s
~:t~f:---d ,!
14 BAA$. 1•-T OC
--
CONCRETE STEPS
SECllON A A
5'-0" Mo\;(
6 ==:::r;i;;r:1 =:::i ii~ w -
~
JOM
i
' •
"'"'
M:=TAl f--.ANDRAIL
NOTES FOR CO'~CRETE STEPS·
CONCRFTF c;;=MFNT cor-.CI{[ 11 U_,\SS :_; :·, :_i ··,
7 All S ff PS SNv1f-_ DlrvTNS ONS 'N!TI-IIN 3/fJ MAX
DIFFERENCF
3-1--Z :::::_Hs 7 ~ /z:' r,lt,,X 5 MIi\
-1 TREADS 12" MAX MIN .• WlTH 1111\·\JS\itHSt:
001 r /FT S.OPE
:i rv':ETAL HANDRAIL RECX, RE'D f-C:,11 4 ~lltY;_; CY. k'(~[
SEE NOTES BE:...ov.;
REINFORCING BARS SHALL MEET Tl-E REOUIREM.:'NTS
OF ASHA A-615 GR.ADE ri [I Ar,..;!) ml lilOUlf--;rn
FOR 4 STEPS OR IV.ORE
SEE SEC J CG
8 r/AX Vt::RTlCAL JIS"J/\NCf:-Btl'N[[N LANDINGS IS 12'
NO-ES FOR HA~{)=v;ILS
L GA .. VANIZED STEEL ffi .t..LUMINUM
2 1 1/4~ TO 2'" O.D. ROLNJ CR OVN_ PIPF
3. V\ILLLJLLJ WlTH. S\100TI I SURFACE AND JOINTS.
4. POSTS SET It~ Ml!\ D cm<CRETE CLASS 3000
5. S'.::E SEC .3.06.
VAAl(S
~
t-f.
•"'~.-. Z··,;<:::c. •ti:";);)~~:+:PSil:.9,;:,_;;;J ,.,,, .. -.. ,,,""'·''"'·:··,:-. ····'----
,,...,_0,.V '9
;.. y .., ~ --lot' C(M[Nl COHcli'CTE .;..,,}~· •,-:
_. ett.£m-CONCRETE -~ . -t. SlOEWAl,J( CEMENT CONCflttE
nlO COLfflY PU!UC WORKS
KING COUNTY. WASHINGTON
L£.I
(m>)
CONCRETE STEPS
122
& METAL HANDRAIL cm,a. 5-008
rn HYDrw.rr Ofl:
UTILITY POU: S1D£wALK NEXT TO "1'.R'TICAL C'JRB
~~ ~~ ~~
\( + \( +
~· M!!i.
----------------------------------------
lUW~R[ ~';--,1~" 1
NOTE L--~~
NOTFS
J
1. TREES SHAL1-GENERALLY BE PLANTED l:lACK OF THE SIDE\'VAf.K
PLANTING SlRIPS WILL BE APPROMD ONLY /JS PART OF A
LANDSCAPII\G PLAN IN \IVHICH PLANT UAINTENANC[, COMPATIBILITY
WITH UTILITIES, AND TRAFFIC S,.:,..FET"' ARE DULY CONSIDERED.
2 IF PlJIJ\ TING STRIPS .ARE APPROVED:
A ~IN. OlSTANCt FROM CENTER OF Al\1Y TREE TO NEAREST
EDGE OF VERTICAL CURB SHALL BE ,~ FEET
B !HttS SH/ILL BE STAKED IN A MANNER NOT TO OBSTRUCT
SIDEWALK TRAFFIC
C IN CASE OF BLOCK-OUTS. MIN CLEAR SIDEWALK ',',1DTI-,
SHALL BE e, FEET IN RE$1DENTLA.L CR 8 FEET IN BL..'SINESS
DISTRICTS.
3 ON BUS ROUTES. PLA~S SHALL BE COORDINATED WlTl-l METRO
SERVICE PLANNING PHONE 684-1622
4 SEE SEC. 5 03.
~ KtlCl cotfflY PUElJC WOR(8
KING COUNTY. WASHINGTON
+
"-----.., J
fi.Alj
STREET TREE
123
!l,O' Wllf
~-~
+
~J
STANDARDS
VERTICAL CURB UHE
Al IN1ERS€COOH
emf· 5-009
V~!l:,:S
'1 1·-0: .!!t-a"
~
9 • S«'i¥Ai.t< '"""'-' _,....--WJL8-0X CLUSTER
! :I® :11!.1:! ;11~;1 ;11~:1:11~~ l1!I vERTICAL OR ROLLED CURB -1-'IERTIC'.L OR RDLLt.O CUR8
91• ~·
'o'CRTICM. CURB J----
J a
IO BOXES 1M.X
N
~
i
FACE OF CUR8
ELEVATION
NOlES
1. FOR THREE OR MORE \,V,.l\..OOXtS ON URBAN RESIDENTIAL ACCESS STREETS
V1'HERE THE SPEED LIMIT IS 25 MPH.
SEE OCTAL
2 MAILBOX HEIGHT VARIES ACCORDING TO THE TYPE OF DELIVERY VEHICLE THES::
HEIGr'TS SHALL BE DETERMINED BY ME PQSTMAS~ER WRING PL.AN R'v1EW
J. MAILBOXES MUST BE POSTMASTER APPROVED WlfH 1\ l.NIFORM ROX STYLE ANJ
rv'ETHOD OF ADD~ESS IDEt'lTIFICATION.
4 LOCATION OF MAILBOXES SUBJECT TO APPROVAL OF THE REVIEWING AG::'.·JCY
5 'NOJO POSTS SHALL BE ~RESSJRE TRE•\TED FIR OR HEMLOCK
6. FOR MAILBOX CLUSTER UJCATION IN S~OULDER SECTION SEE D,\G !\JO 5-011
7 SEE SEC 5-04.
8. OPTIONAi... NE\NSPAP::R BOX STRUCTURES Ar£ SUBJECT l O APPROVAL OF
REVIEWING AGENCY
(i) KtlQ COLfflY PIJ3UC WORKS
KING COUNTY, WASHINGTON MAILBOX MOUNTING
124
,.,
b
'
' ' .
filM!1
(:_~. 0\1£RwJ,IC Ul:H $1[)(
~:-0'"
.(' X _.. WOOO POST
SECI!OM A-A
CURB TYPE LOCATION
SH.I.X[S. ASPI-W. T St«NGLES. OR TJlES
1 /i' EXT. Pt. 'l'WOOD
CQYCll CAB!.£ ENOS
WITH 1/'1" EXT. PL'NIIOOD
TRWiGL( -1r)(tf,x1!,
2 X ll BOLTEO
, x ,. x a·
emf· 5-010
~-~-~-~-~-~-~~~-~-~-~-~-~-~
DjR[CTION or llWTIC --
~ EOG( or SHOULDER
<ll·J ~
14' l,t!."I.
NOTES:
SEE SEC. 5.04.
[> + p I
WU19J1~1J1HJmllia lr/'~8·~; I ~!~
EOl;E or l~vtLEO WAY~
lt-> ,,.~~ I ~· t.llN
MAILBOX TURNOUT roiq SHOULD[fl: llllDiHS l[5S THAN ,r-cr l
£1At!
,. m>. I-.
10 BOKES WAX. • i
E1.E\1AIION
2. MAILBOX INSTAll..AT!ONS ON PROJECTS FUNDED 8Y FEDERAL GRANTS SHALL BE
CONSTRUCTED IN ACCORDANCE WITH WSOOT/APWA STANDARD PLAN H-12.
J. REVIEWING AGENC¥ MAY APPRO\/E INSTALLATIONS OF MAILBOXES WITHOUT
TURNOUT IF CONSTRUCTED IN CONFORMANCE WITH WSDOT/P.PWA STANDARD
Pl.AN H-12.
4. MAILBOX HEIGHT VARIES ACCORDING TO THE TYPE OF DELIVERY VEHICLE.
THESE HEIGHTS SHAU. BE 0[T£Rt.llNED BY THE P0STMA.ST£R DURING PLAN
R~l[W.
I·
Ci) KNG CCUITY PU3UC WOFl(S
KING COUNT'f, WASHINGTON MAILBOX MOUNTING
125
2"
,.,
b :;
Jllli!l.
IQ'-0"' MIN.
5££ O[T,'.IL
SECTION A-1,
SHOULDER TYPE
SKA.KES, ASPI-W.T SH1NGLf5 OR TILE."S
1 /t' m PL Y\IIIOCO
,,,,,.,-~'j;RI ;?t·~-r~ YWOOO
lRWK;L[ -27"X!fj")(jfj
2 X IS B0L1E0
-4 x 4 X 8'
< ~ ~ EACH S'DE
4" X 4• WOOO POST
!It
LOCATION DWG. 5-011
NO.
ffl .---
""""'ON .>OINT 9t
: I • ,
• l• ..
~~·aini ·~,Wt.,_
T(t.tPlA1t
~
"'' '
~ SEE .on: NO 2 I .. ; ,·_ ... '1
,-
llilliI
NOlES:
1 SEE SEC. ~.04.
2 INSTAL.lATION OF N.D.C.B.U. (INCLUDING CONSTRUCTION OF
BASE) WILL BE DONE BY U.S. POSTAL SE"RVICE
3. SEE SEC. 3.04 FOR JOINT REQUIREMENTS
1 '-<
I
2·-r
,------,
I I r-----,
I I ,------,
L _____ _J
I l
=' I l
PL»rnNG STRIP W\OTH
0 TO VAAt.l81._[ I I I
I rl ,.?( -1?:. I/
c__, • . .
•I I~ 1 ,.
' C _,,,, ..
5'E ••'1£ NO. 2 __/ t' ' -o
I
"~ J
~
_MlN. ~·-r:t <::LE;AA WIOTH
IIQUt(J ON PEOESTAL
PROI/IDED WITH
N.O.C.(UI. llNfT
[XPAHSIO'-JOINT
, ,
(i) KtlQ COltlTY P\8.IC WOll(8
KING COUNTY, WASHINGTON
NEIGHBORHOOD DELIVERY & COLLECTION BOX UNIT
JN.D.C.B.U.) MAILBOX INST ALLA Tl ON
126
OWG. 5-012 NO.
1· CHN,ff[~ 4 SIDES
REC"i'CL!D Pl.ASllC
CR liM9[R 1
1/S-UIN. 1HICXNESS
C;.lLVA.NIZ(O STEEL OR
;.LUMIMUW. INTEfllOR
S10£ O!MENSIONS 1/4-
0R[AT[fl lHAH POST
OH,IENSIONS.
NOTES
~
1£
REMOVAAI E AOl lARD
SECTION A-A
~ )C ~ X 4'-r;f
"' ' "
1/T GAL..-~1up EYE: aou
W/WASHER N.0 NUT. RECESS
t.1\JT A.ND PWi BOLT THR().()S
I soo, fillN. lF.ST 00VAN1l£D
CI-WN ANCI-IOR[D IN CONCRETE
"' ' h
=.(ECYCLED f'LASTIC BOLLARD SHALL BE WHIT!:: TIMBER SHALL BE
DOUGLAS FIR. DENSE CONSTRUCTION GRADE, AND SHALL BE
1--'l~J-:SSUl~F TREATED WrTH A VVATERBORNE PRESERVATIVE (ACA CCA.
ACZAJ 1r,.. ACCORDANCE WITH THC: REQUIREMENTS OF SEC'. 9-M.~
(4) OF THE WSOOT/APWA STAS.:DARD SPECIFICATIONS. TOP 5"' OF
TIMBER SHAlL BE 1--'AINTED V\/HITE
2 STEEL TUBE SHALL CONFO.:C<.M TO ASTM ~'5 GRADE A
3 NUTS BOLTS. &. W/\SHFRS SHALL CONFORM TO ASTI,1 A.;.07.
4 ALL STEEL PARTS SHALL BE GALVANIZED
5 CONCRETE SHALL BE CLASS JOOO.
6. SEE SEC. 5 08
"f. MIN. 5 6 SPACING ON TRAILS LESS Tl IAN "\ D' WIDE 6 6 SPACING
ON TP..AJLS 1 D' OR WIDER.
<e> KNCl COUKrY PUll.JC WOfl(S
KING COUNTY, W.ASHINGTON
<
M:C'l'tl!D P~C
OR 111.IDUt I
If' X ff X ~·-6""
I ~ ~ j~
<
RFMOVARIE 801\ARD
£1.Atj
BOLLARDS
127
I" CH,IJ,lfER 4 SIDES
i
"' ~
"i
~
FIXED BQI I ARQ
l:\Yt9· 5-01 3
.}./>•
,.L._I r
~,=a_
--tJ.-
A
SECT\ON OE l filER
PORTLANO CEW£Nl
CONCRCT[ PA\'EWENT
--;::-"" "
PLAN 1 COVER
R-!!, 1 ,t"
"(~ .. .,;.-
"! • .• l. ,.
,
• ~. ~· ·~. 'lo
~ ~-1/4~
~ ---~
~-
N
!!~~ ,;~
R•J_JL:<
.• :·_ ··!.:-~.-. I' R•J ';'" :I • ., -~ •, _, i .;-_; R•J 7 ~
P. C. C~~~ ,,_'"' ~. 11:•-4' .....
r,:t1 II. 4.
"'
PIPE MONUMENT -
T c;;AlYANIZEO IRON Pl"£
""" OONCRm CORI'
SECTION A A.
R•~ J/<
A
'
NOTES:
1. CASTINGS SHALL BE GRAY IRON -'$TM
MB. AASHTO M 105, CL.ASS 30.
2 COVER AJI.ID SEAT SHALL BE MACHJNEO
FOR PERF'E:CT CONTACT AROUND
CtRCU~FERENCE AND FULL WIDTH OF
BEARING SURF ACL
3. APPROXIMATE
CASE
COVER
TOT.Al
WEIGHTS. STANDARD.
60 LBS
1Q LBS
79 LBS
<J PAVEMENT SHALL BE ASPHAl.T CONCRETE:
OR APPROVED SUBSTITUTE.
5. CONCRETE SHALL BE CLASS 4000
'L I.IIN. NOT[ JI
~P,W.T CCN:
PJt.V[WEHT
h
• ~ • • ll.
CRUSH'P "'°'
CONCRETE
MONUMENT
(ALTERNATE)
~ l(J,IQ COUNTY P\8.JC WORKS
KING COUNTY. WASHINGTON ROADWAY SURVEY MONUMENT WITH CASE
128
• ~Tij
&
Pl AN DF MON\JM[NJ
~,,...._ COPPER Pl.VG
OR '""'
... I
~ ..
9H ' ,
·-· ·.u-....
• ' . . , ' ··.· ..
SECTION B-8
COVER
'
~
..
'!,
DWG. 5-014
NO.
NOTE:
COi_;IVr , \ \\G
"-::.. 't-' , }--
S250 FINE t FOR DISTURBING ;i
1/, CHAU.-....._
..J'I'"~~ __.,r:r,_ __il/'r~
TS A343-;::
, r> BM A1362 -; ,<_ VG,, ~ ~'
't' ~<; v(' Y MO\;.\\>
ONLY THE ..s!i!GNED
IOENTirtCATION NUYBCRS
ARE TO APPEM ON T:iE ..... '""'-.flAri
m·~
1-'\,
-<(,,
S£C1IOH A-8
f
'I
s
~,
~ --.-+' G;.-
A
"
\ t \ l t_J
(i)
BRASS DISC
fl fWJION
KtlCl COLfflY PUBUC WORl(S
l<ING COUNTY. WASHINGTON
"' ?a ~ -r
0£TAll OF l,ROO\I[
FOR 1/4" LrntRS
, lfI...
L(~
£f.Alj
" ~ I
O[lolJL OF Gf'!'00,1£
FOR J/115'" L£T'!£AS .r.N() UN~
D
~'
LEDGE ROCK OR
CONCRETE INSTAI LATION
).l0l[;
~~c,.l:11.'"IJ&:
ENOUGH TO
a.EAA IW!KER
1 \/'!" AT
ALL POINTS
-. !
~f~i
b ,;.-r-
t ~3/32'"
' iJ,
SEOt9t+ A fl
-tt .. inL,-;
~ru
SECTION G-C
.. ··;·i·. ' . . . . . ·_ . · .. ~ · . .-. '::.:.
.. . . : .
!·.·:·,4'·~
' •.•. !
1'-(t'" WIN
..
.~~ERAl INSTALi AT/ON
SECJ!ON D-P
~:
OFF-ROADWAY SURVEY
129
NOTES;
THE BRASS DISC SHALL BE Ci\ST ;Jf Ya.LOVV
BHASS S1\t 41
2. CONCRI: Tl SH/ILL L~t CL/\SS 4000
3 Tl IE HOLE SHAc.L 8[ 2.5' MIN IN D[PTH OR 0.5'
BELO/'/ THE DEEPEST RECORCED FROST LINE. ALL
LOOSE MATERIAL Sr'.ALL BE REMOVED FRO'v1 THE
BOTIO~ OF THE HOLE SO THAT THE CO~CRETE IS
ON FIRM UNO:STURBED EARTH
4 -HE TOP OF THE CONCRETE: SHALL BE TROWLED
SMOOlH ANlJ 1r1:_ DRJ\SS DISC St.I IN ·:-it::. Ci::.Nlt:.K
WITH ITS TOP EDGC FLUSf--i AND LEVEL
5. COORDINATES OR :::LEVATIONS SrlALL N:r
G[ Pl ... ACrn ON THE BRASS OlSCS
MONUMENT DWG. 5-015
NO.
King County
KING COUNTY
COMPREHENSIVE PLAN 2004
Adopted September 2004
King County Department of Development and Environmenta'r'Services
900 Oakesdale Avenue Southwest
Renton, WA 98055-1219
http://www.metrokc.gov/ddes/compplan/
For Alternate Formats call 206-296-6600
Table 01 Contents
King Countv Comprehensive Plan 2004
Published January 2005
Introduction
Chapter One -Regional Planning
I. Defining Regional Objectives
11. Planning Framework
A. Multi-County Planning
B. Countywide Planning
C. Subarea Planning
D. Functional Planning
E. Neighborhood Planning
Ill. Comprehensive Plan Amendments
IV. Review and Evaluation
Chapter Two -Urban Communities
I. Urban Land Use
11.
Ill.
IV.
A. Urban Communities
B. Residential Land Use
C. Commercial Land Use
D. Urban Planned Developments (UPDs) and Fully Contained Communities
(FCCS)
E. Urban Separators and the Four-to-One Program
Potential Annexation Areas
Economic Development
A. Overview
B. Business Development -Creation, Retention, Expansion. and Recruitment
C. Workforce Development -Skilled Workers, Employer Involvement and
Economic Opportunities
D. Regional Plans, Regional Projects and Public Private Partnerships
Housing
A. Housing Choice and Opportunity Throughout King County
1-1
1 -1
1-3
1-5
1-5
1-5
1-6
1-6
1-7
1-9
1-11
2-1
2-2
2-2
2-8
2-12
2-1 B
2-21
2-23
2-26
2-26
2-27
2-29
2-30
2-32
2-32
Table of Contents -1 September 2004
B. Affordable Housing Development 2-34
C. Preservation of Existing Affordable Housing 2-36
D. Access to Housing 2-37
E. Reducing Development Costs 2-38
F. New Housing Models 2-39
G. Direct Assistance to Households 2-39
H. Balancing Jobs and Housing 2-40
V. Human Services 2-41
A. King County's Role in Human Services 2-41
B. King County's Human Service Goals 2-42
C. Assessing Use of Resources and Achievement of Goals 2-43
VI. Sustainable Development 2-44
A. Sustainable Development for King County Capital Improvement Projects 2-44
B. Sustainable Development in the Private Sector 2-44
C. Low-Impact Development 2-45
Chapter Three -Rural Legacy and Natural Resource Lands 3-1
I. Rural Legacy 3-3
A. Maintaining Rural Lifestyle 3-3
B. Forestry in the Rural Area 3-6
C. Farming in the Rural Area 3-7
D. Equestrian Communities 3-B
II. Rural Densities and Development 3-10
A. Rural Growth Forest 3-1 O
B. Residential Densities 3-1 O
C. Transfer of Development Rights Program 3-13
D. Nonresidential Uses 3-15
E. Character/Development Standards 3-16
F. Sustainable Development 3-17
G. Low-Impact Development 3-17
Ill. Rural Public Facilities and Service 3-18
IV. Rural Cities, Towns and Neighborhoods 3-19
A. Rural Cities 3-19
B. Rural Towns 3-19
C. Rural Neighborhoods 3-21
D. Nonresource Industrial Uses and Development Standards in the Rural Area 3-22
V. Resource Lands 3-24
A. Resource Conservation Strategy 3-25
B. Forestry 3-28
C. Agriculture 3-32
D. Mineral Resources 3-36
E. Mineral Resources Property Information for Mineral Resources Map 3-49
Chapter Four -Environment 4-1
I. Natural Environment 4-2
A. Protection and Regulation 4-2
B. Air Quality 4-5
C. Water Resources 4-B
D. Erosion and Landslide Hazards 4-16
E. Fish and Wildlife 4-19
F. Soils and Organics 4-23
II. Endangered Species Act 4-26
Chapter Five -Parks, Open Sp'ace and Cultural Resources 5-1
September 2004 Table of Contents -2
I. Parks, Recreation and Open Space
A. The Regional Open System of Parks, Trails, Natural Areas and Working
5-2
5-2
5-3
5-3
5-6
5-8
5-8
5-9
5-9
5-9
II.
Resource Lands
B. Local Parks
C. Components of the Regional Open Space System
D. Achieving the Open Space System
Cultural Resources
A. Arts
B. Historic Preservation
C. Public Art
D. Heritage
E. Cooperation
F. Stewardship of Cultural Resources
Chapter Six -Transportation
I. Regional System
A. Countywide Transportation Service Provider
B. Public Transportation
C. Regional and Freight Mobility
D. Transportation and Demand Management
II. Linking Transportation Infrastructure and Services with Growth
A. Land Use
B. Travel Forecasts
C. Level of Service Standards
D. Concurrency
E. Mode Split
Ill. Transportation System Planning and Design
A. Arterials and Streets
B. Public Transportation Strategies
C. Nonmotorized Transportation
D. Air Quality
IV. Finance
A. Funding Capabilities: Road-Related Sources
B. Revenue Shortfall
C. Urban Unincorporated Area Road Financing
V. Coordination
VI. Implementation and Monitoring
VII. Transportation Element: Requirements and Components
A. Land Use Assumptions
B. Estimated Traffic Impacts to State-Owned Facilities
C. An Inventory of Transportation Facilities and Services
D. Level of Service Standards Including Standards for State Routes
E. Actions to Bring Facilities into Compliance
F. Traffic Forecasts for at Least Ten Years
G. State and Local Transportation Needs to Meet Current and Future
Demands
H. Analysis of Funding Capability
I. Intergovernmental Coordination
J. Concurrency
K. Consistency of Plans
Chapter Seven -Services, Facilities and Utilities
I. Regional Services
I I. Facilities and Services
Table of Contents -3
5-10
5-10
6-1
6-2
6-2
6-3
6-5
6-5
6-7
6-7
6-8
6-8
6-9
6-10
6-11
6-11
6-12
6-13
6-14
6-16
6-16
6-16
6-17
6-19
6-20
6-21
6-21
6-21
6-21
6-21
6-21
6-22
6-22
6-22
6-22
6-22
6-22
7-1
7-2
7-3
September 2004
A. Providing a Spectrum of Services
B. Urban and Rural Services
C. Identifying Needs for Facilities and Services
D. Capital Facility Planning
E. Addressing Service Deficiencies
F. Financing Strategies
G. Essential Public Facilities
H. Water Supply
I. Public Sewers and On-site Wastewater Treatment and Disposal Systems
Ill.
J. Solid Waste
K. Surface Water Management
L. Floodplain Management
Energy and Telecommunications
A. Energy
B. Telecommunications
Chapter Eight -Community Plans
I. Bear Creek
II. East Sammamish
Ill. Enumclaw
IV. Federal Way
V. Highline
VI. Newcastle
VI I. Norths ho re
VI 11. Shoreline
IX. Snoqualmie Valley
X. Soos Creek
XI. Tahoma/Raven Heights
XII. Vashon
XIII. West Hill/White Center
Chapter Nine -Implementation
I. Land Use Designations and Zoning Classifications/Code
11. Other Implementing King County Codes
Ill. Incentives
Glossary
Ordinance
List of Maps
Chapter One //
Land Use Map
Chapter Two
Interim Potential Annexation Areas Map /
Urban Centers Map
Chapter Three
Agricultural and Forest Lands Map
Equestrian Communities Map
Mineral Resources 2004 V
V
September 2004 Table of Contents -4
7-3
7-3
7-3
7-4
7-5
7-5
7-6
7-7
7-11
7-13
7-14
7-15
7-16
7-16
7-22
8-1
8-2
8-5
8-9
8-11
8-12
8-13
8-14
8-17
8-18
8-27
8-30
8-32
8-36
9-1
9-2
9-4
9-5
G-1
0-1
1-13
2-47
2-49
3-43
3-45
3-47
Chapter Four
Wildlife Habitat Network and Public Ownership Map 4-29
Chapter Five
Open Space System Map 5-13
Table of Contents -5 September 2004
Introduction
King Counh Co1Dprehensive Plan 2004
A. About King County
King County has some of the most beautiful scenery in the country, some of the most productive
farmlands, and one of the most vibrant economies. The King County Comprehensive Plan 2004
establishes a vision that preserves this incredible diversity while continuing to acknowledge that
citizens want options as to where they live, work and play. The plan guides growth and
development throughout the unincorporated areas of the county and establishes King County's
position on maJor issues such as annexations, regional water supply and environmental
protection.
King County Geography
King County, covering 2,130 square miles, is the size of the state of Delaware, but much more
geographically diverse. It extends from Puget Sound in the west to 8,000-foot Mt. Daniel at the
Cascade crest to the east. King County's various landforms include saltwater coastline, river
floodplains, plateaus, slopes and mountains, punctuated with lakes and salmon streams. Lake
Washington, covering 35 square miles, and Lake Sammamish with 8 square miles are the two
largest bodies of fresh water. Vashon-Maury Island in Puget Sound and Mercer Island in Lake
Washington provide different island environments.
The north-south trending shapes of the lakes and hills make east-west travel more difficult than
north-south travel. Four major river basins with salmon-bearing streams are separated by step-
sided plateaus whose slopes are subject to landslides and erosion.
King County Jurisdictions
As of 2004, there are 39 cities ranging in size from Seattle with 572,000 people to Skykomish and
Beaux Arts with less than 350 each. Since December 1994, five new cities have incorporated,
shifting 120,000 people into city limits. King County's 39 cities cover 383 square miles, or 18% of
the county's total land area. The incorporated population has increased by a total of 327,000
since 1994, primarily due to new cities and large annexations as well as growth within existing
boundaries.
Unincorporated King County, the territory outside any city, now has about 352,000 people or 20%
of the county's population, on 82% of its land area. The unincorporated population has
decreased by 148,000 since the 1994 Comprehensive Plan was initially adopted, chiefly through
the incorporation of new cities.
King County Demographics
In 2004, with more than 1,779,000 people, King County is the largest county in Washington State
and the 13th largest in the nation. As a populous large county with a major central city. King
County constitutes the majority of the "Seattle-Bellevue-Everett" metropolitan area of nearly 2.5
million persons. King County exhibits growing diversity: 73% of the population is non-Hispanic
white, 11 % Asian or Pacific Islander, 5% African-American, 1 % Native American and ((4-%))5.5%
Latino (2000 census).
Introduction -1 September 2004
King County's population has grown by 11 % since 1994, a modest rate compared with Sunbelt
metro areas and nearby Puget Sound counties. However, given the large population already
here, the growth numbers are significant. The population increase since 1994 equals the total
existing population of the cities of Bellevue and Renton. King County is forecasted to grow by an
additional 270,000 persons (15%) to about 2,049,000 by 2022.
The number of housing units in King County is growing at about the same rate as its population.
Now estimated at 775,000 houses, apartment and condominium units and mobile homes,
housing has increased by 83,000 units (12%) since 1994. Household size has stabilized after
declining in the 1970s and 1980s, and is now estimated at 2.39 persons per household. A slight
decline in household size is anticipated in coming years, to about 2.30 in 2022.
King County Economy
More than 1.1 million workers are employed within the borders of King County, at nearly 84,000
business establishments. With more than 40% of Washington state's Jobs and payroll, the county
is truly the economic engine of Washington and the Pacific Northwest. With a 2002 payroll
exceeding $52 billion, the King County economy is larger than that of several U.S. states.
King County has a cyclical economy, with booms and recessions typically on a ten-year cycle.
During the 1990s, the number of jobs grew by 26% to almost 1.2 million, then edged downward
after 2001. Manufacturing employment remains important, but aerospace, the largest sector, has
lost 12,000 jobs since 2001. The economy has diversified from the traditional aerospace and
resource bases to high tech, services and trade, both local and international. Unemployment has
recently increased after several years of historic lows. However, long-term prospects are
favorable for a return to healthy economic growth and further increases in jobs.
B. Planning in King County
King County's comprehensive land use planning dates back to 1964. Its first comprehensive plan
under the State Growth Management Act (GMA) was adopted in 1994. The GMA, passed by the
Washington State Legislature in 1990, seeks to further protect the quality of life in the Pacific
Northwest. The GMA directs the state's most populous and fastest growing counties and their
cities to prepare comprehensive land use plans that anticipate growth for a 20-year horizon.
Comprehensive plans adopted in accordance with GMA must manage growth so that
development is directed to designated urban areas and away from rural areas. The GMA also
requires jurisdictions to designate and protect critical areas and commercially significant forestry,
agriculture, and mining areas. The GMA requires each comprehensive plan to adhere to a set of
thirteen goals and to include the following elements: land use, housing, capital facilities, utilities,
rural, and transportation. The King County Comprehensive Plan 2000 represented the first major
review and the first set of substantive changes since the county's current comprehensive plan
was initially adopted 1n 1994. The 2004 update is the second major review. The 2004 update
also satisfies a state requirement that the county's urban growth area be reviewed every ten
years.
The King Countywide Planning Policies (CPPs) set the framework for the county's and cities'
comprehensive plans. The CPPs, adopted by the county and cities in 1992, establish an Urban
Growth Area (UGA) within the western one-third of King County where most growth and
development is targeted. The goals of the policies include: reducing urban sprawl, protecting
rural areas, providing affordable housing throughout the county and coordinating protection of
environmentally sensitive areas.
September 2004 Introduction -2
C. Summary of the King County Comprehensive Plan
How the Plan is Used
The King County Comprehensive Plan provides a legal framework for making decisions about
land use in unincorporated King County. Public and private agencies, property owners,
developers, community groups and King County staff use the comprehensive plan in several
ways.
First, tne plan is the framework for other plans and regulations such as subarea plans and the
King County Code that govern the location and density of land uses. It provides guidance to
county officials for decisions on proposals such as zoning changes and developments. It also
gives the public direction on the county's position on proposed changes in land use or zoning,
environmental regulations, or broader policy issues. The plan also provides a basis for decisions
about public spending on facilities and services. And, the plan presents other agencies, such as
cities and special purpose districts, with King County's position on large-scale matters such as
annexation, use of resource lands, environmental protection and others.
The GMA allows local comprehensive plan amendments to be considered once each year. In
King County, those annual amendments allow technical changes only, except for once every four
years. Then, during the "Four-Year Cycle review process," substantive changes to policies, land
use designations and the Urban Growth Area boundary can be proposed and adopted.
Following is a summary. by chapter, of the plan:
Chapter One: Regional Planning
The vision and goals of this plan are based on the 13 planning goals specified in the Washington
State Growth Management Act, the Countywide Planning Policies and the values voiced by the
citizens of King County. The official King County Land Use is included in this chapter. This
chapter also describes the county's process for amending the Comprehensive Plan and outlines
and distinguishes the annual cycle and the four-year-cycle amendments.
Chapter Two: Urban Communities
The Urban Communities chapter brings together several of the major elements necessary to
make a community whole: housing, business centers, economic development and human
services. By merging these elements into one chapter, King County emphasizes the importance
each plays as a part of a livable community. A major tenet of the GMA is to target growth in the
urban areas, so the policies in this chapter better facilitate urban development where
infrastructure and facilities exist or can be readily provided.
Chapter Three: Rural Legacy
Protecting a rural way-of-life in King County is a major thrust of the plan. Conserving King
County's rural and natural resource lands integral to providing diversity in lifestyle choices,
continuing farming and forestry economies. protecting environmental quality and wildlife habitat,
and maintaining a link to King County's resource-based heritage.
Chapter Four: Environment
With Chinook salmon and Puget Sound and Coastal Bull trout now listed as threatened species
under the Endangered Species Act, and other species about to Join the list, protecting the
environment is a priority. King County's programs for protecting the environment are some of the
most advanced 1n the country. Protecting and restoring air quality, water resources, soils, and
Introduction -3 September 2004
plant, fish and animal habitats are among King County's primary goals. This chapter establishes
policies to protect the environment and enhance the region's high quality of life,
Chapter Five: Parks, Open Space and Cultural Resources
Protecting and enhancing King County's communities through public funding while encouraging
continued stewardship for county parks, open spaces, recreation, and cultural resources is the
central focus of Chapter Five.
Chapter Six: Transportation
King County will continue to promote a transportation system that provides residents with a range
of transportation choices that respond to both community needs and environmental concerns.
Chapter Seven: Service, Facilities and Utilities
The Growth Management Act requires coordinated planning so that the services required by new
residents and their homes and businesses are available as growth occurs. Needed services
include many that are not provided by King County, such as water supply, local sanitary sewers,
fire protection, schools, energy facilities, and telecommunications. King County does provide
services such as regional wastewater treatment, regional solid waste management, and local
stormwater management. This chapter guides service provision.
Chapter Eight: Community Planning
King County's community plans (except for the Vashon Town Plan, West Hill, and White Center)
are no longer in effect as separately adopted plans. In many cases, however, the plans contain
valuable historical information about King County's communities and often provide background
for the land uses in effect today. Policies from the community plans were retained as part of the
comprehensive plan to recognize the unique characteristics of each community.
Chapter Nine: Implementation
The comprehensive plan policies, development regulations and countywide planning policy
framework have been adopted to achieve the growth management objectives. This chapter
explains the relationship between planning and zoning.
D. Technical Appendices
Integral to the vision and goals of the comprehensive plan are the detailed inventories, forecasts,
finance plans and Urban Growth Area analysis required by the Growth Management Act.
((+llffie))Four technical appendices (Volume 1) are adopted as part of the plan to implement
these Growth Management Act requirements (RCW 36.?0A.070, 36.?0A.110), 36.70A130).
These appendices were updated in 2004. Beginning with 2004, Technical Appendix D was
moved to Volume 1.
Volume 1
Technical Appendix A. Facilities and Services•
Technical Appendix B. Housing
Technical Appendix C. Transportation •
Technical Appendix D. Growth Targets and the Urban Growth Area 2004
Additional important information also supports the plan vision and goals. Nine technical
appendices (Volume II) were prepared to provide supporting documentation to the 1994 plan:
September 2004 Introduction -4
Volume 2
Technical Appendix D.
Technical Appendix E.
Technical Appendix F.
Technical Appendix G.
Technical Appendix H.
Technical Appendix I.
Technical Appendix J.
Technical Appendix K.
Technical Appendix L.
Growth Targets and the Urban Growth Area
Washington State Laws
History of Planning in King County
Economic Development
Natural Resource Lands
Natural Environment
Potential Annexation Areas
King County Functional and Community Plans
Public Involvement Summary
Information that supported amendments subsequent to 1994 are included as follows:
Volume 3
Technical Appendix M. Public Participation Summary 2000'
Volume 4
Technical Appendix N. Public Participation Summary 2004
E. The Regulations
The King County Comprehensive Plan is implemented through the adopted regulations. These
include the King County Zoning Code and other code titles such as Water and Sewer Systems.
Roads and Bridges. and Land Segregation. All development proposals in King County must meet
the requirements of the code.
F. For More Information
Copies of the plan are available in all King County libraries. Please visit the website of the King
County Department of Development and Environmental Services at
http://www.metrokc.gov/ddes/compplan for current information on planning in King County and to
view electronic versions of the plan and related documents.
As required by the GMA, King County maintains a docket for recording comments on the King
County Comprehensive Plan and associated development regulations. Comments logged on the
docket are reviewed by the county and made available for review by the public. The docket is
available on the King County Website at http://www.metrokc.gov/ddes/compplan.
Introduction -5 September 2004
Cha ter One
Regional Planning
Cha ter One
Regional Planning
Passage of the Growth Management Act (GMA) in 1990 by the State Legislature was the first
critical step in the development of rational policies to sustain growth in Washington. For the first
time in the state's history, all urban counties and their cities were required to develop and adopt
comprehensive plans and regulations to implement these plans. To ensure comparable planning
efforts, the Growth Management Act requires that comprehensive plans address specific issues
including, but not limited to: land use, transportation, housing, facilities and services, utilities.
natural environment, and economic development.
To achieve coordinated planning efforts, the Growth Management Act further requires that
counties and cities develop a set of framework policies to guide development of each
jurisdiction's comprehensive plan. In order to implement the Growth Management Act. King
County conducts planning on five different levels. These levels of planning encompass land
areas ranging in size from small neighborhoods to multiple counties.
Five Levels of Plannina for Kin County
Level Purpose Examples
Multi-county Most frequently, multi-county planning is • Metropolitan Transportation
conducted by the Puget Sound Regional Plan
Council and includes King, Pierce, • Regional Benchmarks
Snohomish, and Kitsap Counties. This • Multi-county Economic
level of planning is needed to address Development Strategy
issues that affect the entire Central Puget • Multi-county Planning Policies
Sound req1on.
Countywide This level of planning is conducted by King • Countywide Planning Policies
County in cooperation with the cities to • King County Comprehensive
address a wide range of issues that affect Plan
I the entire county. • Action Plan for Affordable
Housinq ---------·----------·
Subarea This level of planning. previously called • Duwamish Coalition Pro1ect
community plans and basin plans, brings • Fall City Subarea Plan
the policy direction of the comprehensive
plan to a smaller qeoqraphic scale.
---------··---
Functional This level of planning is conducted by King • Parks, Recreation and Open
County, special purpose districts or other Space Plan
agencies. Some plans cover the entire • Regional Wastewater Services
county, while others pertain to specific Plan
areas. Functional plans focus on the • Six-Year Transit Development
delivery ot services or facilities. Plan
Neighborhood These local plans address issues of • White Center Action Plan
concern to individual communities. • Vashon Town Plan
i • Aurora Corridor Study
The Growth Management Act also provides for re-evaluation of the comprehensive plan to
address emerging land use and regulatory issues. The act also calls for jurisdictions to evaluate
September 2004
progress towards the implementation of respective comprehensive plans and countywide
planning policies.
September 2004 1-2
I. Defining Regional Obiectives
Prompted by citizens, King County adopted its first comprehensive plan to manage growth in
1964. Two decades later, the 1985 Comprehensive Plan identified an urban growth boundary
line to limit urban growth to areas with the infrastructure needed for facilities and services. It also
established policies to preserve rural areas, conserve the natural environment and designate
resource lands for long-term agriculture and forest production.
King County played a key role in the development of Vision 2020. a long-range grow1h
management. economic and transportation strategy for the central Puget Sound region. Vision
2020, developed by the Puget Sound Regional Council (PSRC), outlines a growth management
and transportation strategy under state and federal laws. Member counties and cities of the
PSRC adopted Vision 2020 in 1 990.
The Grow1h Management Act (GMA), adopted by the state legislature ,n 1990, requires urban
counties to develop comprehensive land use plans addressing growth. The GMA also requires
counties and cities to work together to develop framework policies to guide the comprehensive
plan development. These Countywide Planning Policies (CPP), first adopted in 1992, establish a
vision for the future of King County-its cities, unincorporated urban areas, rural areas, and farms
and forests. Under the CPP vision for the year 2022, King County will boast a diversified sound
regional economy and high quality of life with a defined rural area, busy urban centers linked by a
high capacity transit system and preservation of many natural areas.
King County's comprehensive plan builds on this vision for the unincorporated part of the county.
The county's first comprehensive plan under the GMA was adopted in 1994. The 2004 update
continues to be based on not only the mandates of the law, but also the goals voiced by citizens
during the 1994 plan process and repeated during the plan update process.
The policies in this plan support the following objectives, which reflect the GMA goals, the CPP
and public opinion:
• Preserve the high quality of life by balancing infrastructure needs with social, cultural,
educational, recreational, civic, health and safety needs.
• Spend money wisely and deliver services efficiently by:
• Concentrating infrastructure investments and service delivery to support the regional
development pattern near cities where a full range of local services are located or can be
made available:
• Solving service deficiencies within the county to meet existing service needs and phasing
service improvements for the needs of future growth;
• Looking to King County to provide countywide facilities and services: and
• Relying primarily upon cities and special purpose districts as the providers of local
facilities and services appropriate to serve those local needs, except where the county is
the local service provider (e.g., rural area).
• Continue our economic prosperity by promoting a strong and diverse economy for King
County residents through policies and programs that encourage new business opportunities,
increase family wage jobs and create a predictable regulatory environment for businesses
and citizens.
• Increase the housing choices for all residents by permitting a wide variety of home styles
and by increasing the housing opportunities for all residents in locations closer to jobs.
1-3 September 2004
• Ensure that necessary transportation facilities and services are available to serve
development at the time of occupancy and use by targeting road and transit investments
where growth is desired and for equitable contributions to the transportation system by new
development.
• Balance urban uses and environmental protection through careful site planning that
maximizes developable land while respecting natural systems.
• Preserve rural, resource and ecologically fragile areas for future generations by
maintaining low residential densities in the rural areas and in areas containing regionally and
nationally important ecosystems for fish and wildlife and by recognizing that resource lands,
such as farms and forests, provide economic, social and environmental benefits.
To help achieve these goals, this King County Comprehensive Plan 2004 Update:
• Includes strategies to address the problems of growth;
• Renews emphasis on environmental protection in light of listings of Chinook salmon and bull
trout as threatened species under the federal Endangered Species Act;
• Calls for the county to continue to work with its citizens and other jurisdictions to tackle issues
and develop solutions consistent with community values; and
• Brings together the elements needed to guide growth and development in unincorporated
King County toward the goal of a thriving, healthy and environmentally sound county.
The general policies in this section call on King County to strive to provide a high quality of life,
actively solicit citizen participation, and use its planning processes to strengthen communities.
RP-101 King County shall strive to provide a high quality of life for its residents by
working with cities, special purpose districts and residents to develop
attractive, safe and accessible urban communities, retain rural character and
rural neighborhoods, support economic development, maintain resource
lands and preserve the natural environment.
RP-102 King County shall actively solicit citizen participation from individuals and
organized groups, including Unincorporated Area Councils, in the
development and implementation of its plans.
RP-103 King County shall seek comment during its planning processes from
federally-recognized tribes.
RP-104 King County's planning should strengthen communities by addressing all the
issues, resources and needs that make a community whole, including land
use, transit, health, human services, natural environment and the provision of
infrastructure and other services.
RP-105 King County shall integrate responses to the listings under the Endangered
Species Act into future planning and economic development efforts and
resource management programs to achieve a balance between
environmental, social and economic goals and objectives.
RP-106 The Urban Growth Area line is considered long-term and can only be
amended consistent with Countywide Planning Policy FW-1, and
comprehensive plan policies contained in this plan.
RP-107 The Comprehensive Plan Land Use Map is adopted as part of this plan. It
depicts the Urban Growth Area, rural area, natural resource lands and other
land uses. The Land Use Map at the end of this chapter generally represents
the official Comprehensive Plan Land Use Map.
September 2004 1-4
-
)
II. Planning Framework
There is a hierarchy of planning in the county with consistency between the levels. Some issues,
such as the establishment of the Urban Growth Area (UGA). are best decided at the countywide
level, while others, such as the amount of commercial space needed in a neighborhood. are best
determined at the subarea plan level. The county will move over time to become both a regional
and a rural government, without responsibility for land use planning on a local level with the UGA.
This transition will be gradual, depending on the desires of local communities and the ability of
cities to provide services to newly annexed areas.
RP-201 King County's planning should include multi-county, countywide, subarea
and neighborhood levels of planning. Working with citizens, special purpose
districts and cities as planning partners, the county shall strive to balance the
differing needs identified across or within plans at these geographic levels.
A. Multi-County Planning
The Growth Management Act states that multi-county planning must be done tor the tour-county
region encompassing King, Pierce, Snohomish, and Kitsap Counties. This requirement was
fulfilled by the Puget Sound Regional Council (PSRC) through the creation of the Multi-county
Planning Policies. Multi-county planning will continue to be conducted under the auspices of the
Puget Sound Regional Council with participation by the four counties. Other examples of multi-
county planning include the Regional Transportation Plan, Regional Benchmarks and the Multi-
county Economic Development Strategy.
B. Countywide Planning
Countywide planning is conducted by King County in cooperation with the cities to address a wide
range of issues that affect the entire county. State law requires that planning be coordinated on a
countywide level, and that the county itself adopt a comprehensive plan to regulate those areas it
has director responsibility for. The Countywide Planning Policies, adopted by the Metropolitan
King County Council and ratified by the cities within the county in 1992, are revised on an
ongoing basis to implement the Growth Management Act and to meet the state requirement for
countywide planning.
The Countywide Planning Policies describe an overall vision for the cities and unincorporated
portions of King County, and provide general strategies and approaches to be used by local
jurisdictions. acting individually and cooperatively, to achieve that vision. The Countywide
Planning Policies were developed by a formal body, the Growth Management Planning Council
(GMPC) which consists of elected officials from Seattle, the suburban cities and King County with
ex-officio members from the special purpose districts from the Port of Seattle. The GMPC meets
regularly to review issues of countywide significance and propose amendments to the
Countywide Planning Policies.
King County, the City of Seattle, Bellevue, and the other cities and towns of King County are
responsible for ensuring that their respective comprehensive plans are consistent with and
implement the Countywide Planning Policies. As the regional government, King County provides
leadership on issues of countywide importance. The county should continue to emphasize
implementation of the Countywide Planning Policies when engaged in planning and negotiating
1-5 September 2004
activities with cities and other service providers. Examples of such opportunities include Potential
Annexation Area, preannexation, and other interlocal agreements.
The King County Comprehensive Plan provides policy guidance for unincorporated King County.
The comprehensive plan addresses all of the mandatory and several of the optional elements of
the State Growth Management Act. The plan serves as a vital guide to the future and provides a
framework for managing change.
RP-202 King County shall implement the Countywide Planning Policies through its
comprehensive plan and through Potential Annexation Area, preannexation
and other interlocal agreements with the cities.
C. Subarea Planning
Subarea planning, previously called community planning and basin planning, focuses the policy
direction of the comprehensive plan to a smaller geographic area. Examples include the Fall City
Subarea Plan, and planning efforts within a watershed or basin. Development of subarea plans
are guided by the following policy as well as other applicable policies of the comprehensive plan.
RP-203 Subarea plans provide detailed land use plans for local geographic areas.
Subarea plans implement and shall be elements of the King County
Comprehensive Plan and shall be consistent with the plan's policies,
development regulations and Land Use Map. The subarea plans should be
consistent with functional plans' facility and service standards. The subarea
plans may include, but are not limited to:
a. Identification of policies in the comprehensive plan that apply to the
subarea;
b. Review and update of applicable community plan policies;
c. Specific land uses and implementing zoning, consistent with the
comprehensive plan;
d. Identification of the boundaries of Unincorporated Activity Centers and
Rural Towns;
e. Recommendations for the establishment of new Unincorporated Activity
Centers, Community and Neighborhood Business Centers, if appropriate;
f. Recommendations for additional Open Space designations and park
sites;
g. Recommendations for capital improvements, the means and schedule for
providing them and amendments to functional plans to support planned
land uses;
h. Resolution of land use and service issues in Potential Annexation Areas;
i. Identification of new issues that need resolution at a countywide level;
and,
j. Identification of all necessary implementing measures needed to carry out
the plan.
D. Functional Planning
Functional plans are detailed plans for facilities and services and also include action plans and
programs for other governmental activities. Sarne functional plans are operational or
programmatic and guide daily management decisions. Others include specific details of facility
design and location. _Plans that guide specific siting of facilities must be consistent with the
comprehensive plan. Functional plans are prepared by King County, independent special
purpose districts or other public and private agencies. The Regional Wastewater Services Plan,
which plans for conveyance, treatment and disposal of sewage, is an example of a functional
September 2004 1-6
111. Comprehensive Plan Amendments
In the process of implementing the comprehensive plan, there may be a need for amendments to
address emerging land use and regulatory issues. The county has established the
comprehensive plan amendment process to enable individual citizens, businesses, community
groups, cities, county departments and others to propose changes to existing comprehensive
plan policies and development regulations. This process provides for continuous and systematic
review of comprehensive plan policies and development regulations in response to changing
conditions and circumstances impacting growth and development throughout King County.
The comprehensive plan amendment process includes and annual cycle and a four-year cycle.
The_annual cycle generally is limited to those amendments that propose technical changes. The
four-year cycle is designed to address amendments that propose substantive changes. This
amendment process, based on a defined cycle, provides the measure of certainty and
predictability necessary to allow for new land use initiatives to work. By allowing annual
amendments, the process provides sufficient flexibility to account for technical adjustments or
changed circumstances. The process requires early and continuous public involvement and
necessitates meaningful public dialogue.
King County has established a docket process to facilitate public involvement and participation in
the comprehensive plan amendment process in accordance with RCW 36.?0A.470. Parties
interested in proposing changes to existing comprehensive plan policies, development
regulations, land use designations, zoning, or other components of the plan can obtain and
complete a docket form outlining the proposed amendment. Docket forms are available via the
King County Web site at: http://www.metrokc.gov/ddes/compplan/.
RP-301
RP-302
RP-303
RP-304
RP-305
The amendment process shall provide continuing review and evaluation of
comprehensive plan policies and development regulations.
Through the amendment process, King County Comprehensive Plan policies
and supporting development regulations shall be subject to review,
evaluation, and amendment according to an annual cycle and a four-year
cycle in accordance with RCW 36.70A.130 (1) and (2).
The annual cycle shall consider proposed amendments which do not require
substantive changes to comprehensive plan policies and development
regulations, or which do not alter the Urban Growth Area (UGA) Boundary. If
the proposed amendments are necessary for the protection and recovery of
threatened and endangered species, then subarea plans and proposals for a 4
to 1 project can be considered as part of the annual cycle.
The four-year cycle shall consider proposed amendments that could be
considered in the annual cycle and also those outside the scope of the annual
cycle, proposed amendments relating to substantive changes to
comprehensive plan policies and development regulations, and proposals to
alter the Urban Growth Area Boundary in accordance with applicable
provisions of Countywide Planning Policy FW-1.
In accordance with RCW 36.?0A.140 and the State Environmental Policy Act,
as applicable, King County shall ensure public participation in the
1-9 September 2004
amendment process for comprehensive plan policies and development
regulations. King County shall disseminate information regarding public
involvement in the comprehensive plan amendment process, including, but
not limited to, the following: description of procedures and schedules for
proposing amendments to comprehensive plan policies and development
regulations; guidelines for participating in the docket process; public
meetings to obtain comments from the public or other agencies; provision of
public review documents; and dissemination of information relating to the
comprehensive plan amendment process on the Internet or through other
methods.
The following policies guide the preparation of amendments and their review by King County.
RP-306
RP-307
RP-308
Amendments to the Comprehensive Plan Land Use Map are subject to the
requirements listed in policies RP-307 and RP-308.
Proposed amendments each calendar year shall be considered by the
Metropolitan King County Council concurrently so that the cumulative effect
of the proposals can be determined. All proposed Comprehensive Plan
amendments should include the following elements:
a. A detailed statement of what is proposed to be changed and why;
b. A statement of anticipated impacts of the change, including geographic
area affected and issues presented;
c. A demonstration of why existing comprehensive plan guidance should
not continue in effect or why existing criteria no longer apply;
d. A statement of how the amendment complies with the Growth
Management Act's goals and specific requirements;
e. A statement of how the amendment complies with the Countywide
Planning Policies;
f. A statement of how functional plans and capital improvement programs
support the change; and
g. Public review of the recommended change, necessary implementation
(including area zoning if appropriate) and alternatives.
Proposed amendments to the comprehensive plan policies should be
accompanied by any changes to development regulations, modifications to
capital improvement programs, subarea, neighborhood, and functional plans
required for implementation so that regulations will be consistent with the
plan.
A financial analysis is critical to all subarea, functional and neighborhood plans in order to
evaluate the resources required and the time frame necessary for full implementation. Plan
alternatives and costs should be clearly understood and plans should be financially achievable.
RP-309 King County should identify the financial costs and public benefits of
proposed subarea, functional and neighborhood plans prior to adoption to
ensure that implementation can be appropriately prioritized.
September2004 1-10
IV. Review and Evaluation
In accordance with the Growth Management Act (GMA), King County and its cities have
developed a Review and Evaluation Program in order to collect and review information relating to
a variety of critical land use planning issues. The purpose of the Review and Evaluation Program
is to provide policy makers, business leaders, cities, other agencies, and the public with
information to evaluate the progress made by jurisdictions on the implementation of the
respective comprehensive plan and Countywide Planning Policies.
The Review and Evaluation Program involves a combination of implementation, monitoring, and
reporting or information relating to critical countywide measures and indicators. This information
is furnished through annual publications such as The King County Annual Growth Report and The
King County Benchmark Report. King County collects and reviews information relating to and
including. but not limited to, the following:
• Urban densities;
• Remaining land capacity (buildable lands);
• Growth and development assumptions, targets, and objectives;
• Residential, commercial, and industrial development;
, Transportation;
, Affordable housing:
, Economic development; and
• Environmental quality.
Working in cooperation with the Growth Management Planning Council and the cities, King
County evaluates data collected countyw1de and publishes the King County Annual Growth
Report and the King County Benchmark Report. In addition, on an on-going basis, King County
prepares and transmits progress reports to the Washington State Department of Community,
Trade and Economic Development.
Some of the objectives of the Review and Evaluation Program include:
• Determining whether a county and its cities are achieving urban densities within urban growth
areas by comparing growth and development assumptions, targets, and obJectives contained
in the Countywide Planning Policies and the county and city comprehensive plans with actual
growth and development in the county and cities.
• Determining whether there is sufficient suitable land to accommodate applicable county-wide
population projections:
• Determining the actual density of housing constructed within the UGA since the adoption of,
or since the most recent evaluation of the comprehensive plan;
• Determining the actual amount of land developed for commercial and industrial uses within
the UGA since the adoption of, or since the most recent evaluation of the comprehensive
plan;
, Reviewing commercial, industrial, and housing needs by type and density range to determine
the amount of land needed for commercial, industrial, and housing for the remaining portion
of the twenty-year planning period used in the most recently adopted comprehensive plan;
and
, Adopting and implementing measures intended to promote consistency between estimates of
available land capacity, measures of actual development by type, and goals and objectives of
city and county comprehensive plan policies, development regulations, and Countywide
Planning Policies. Such measures include, but are not limited to possible amendments to
Countywide Planning Policies as determined necessary by the county and the cities.
1-11 September 2004
RP-401
March 2004
King County shall, in conjunction with the cities in accordance with the
Countywide Planning Policies, conduct a Review and Evaluation Program to
determine whether it is achieving needed urban densities within the Urban
Growth Area. If necessary, the evaluation should also identify measures,
other than adjusting the UGA, that can be taken to comply with the GMA.
I
I
I '.)
i t · I
\\ /
) J
/ I
( )
\ '
J. -
\ ,,
~ / .
' / -·-·--·
K ng Co unty Comprehensive Pl an . 2004
Chao ler On e, Regional Planning
rr).'to ·~1;n o ~:s'-i':o-pl:\n'.20Q4\2004 _cp u mxd
Pa-1<
AW'::, ','sd:lvs?O l";J•!l· .... VT' "'-PS\200"' i21200.._KCCP'o4'o 'o'{('_:i:004 1 2Z:_cpl u.pdf
Sr,<>lw'>ffl,!J'I Countf ·---·-.• ·-...,w""I-· .
The 1n'o 1mation included on this m."'lp has been comr:•!!d l)oJ
K 09 :;;;iu nty $'.-'.!!f lrom a '1131 ety d scurces and 1s subif'd to chang e
withou: notice King County makes no re oreseruatk:lns or
wa rra rltit!S upress c, in"l:llied. as to i i:=:v r.a:y, ,;¢rrpcten(.'S~.
hrrtflline,.,; Of ngh!s t:> the 11se cl s.ch inloimarion. '<.og Col,/rt.y
!ha H nol be lia'=ile l o, a ny gen era , special. indrect. i'1ddvnta.l Of
COMequer.t~I dam3ges inck1::l1 ·,9 , but not ,m tt1d to, IMt
rev en ues or lost ~rofos resulti ·<J !•em th~ use or mi&use cf thA
intcrm.liion cc>n.o.t ~e d oii this m.ip ,\ny sale oi this map °" The maps in the King County Cornpretiensive Plan and ,ts technical appendiees are prOduced wirn a compute r geographiC
inlcrm.l:ion on ths n-..ip 1s proh ibi1ed e xc e i:-: by w11t1e r permaS~on c l informatkx, system. They are reduced in size b l jr a.va.J!able at a larger sr.alc .
Ki ng Cou nty
; Ji'/\ I / i \ / ~
'·,
___ .)
j!,_.,_,.,}t
/ ~-,.-··
(
\
)
i
\
i
\..
' (
\.
c..--~-~-~-,Jj
(
i I /I.I> I . N \ I ·.\ ~
,,,....-. ,i l ---·,)
(
,...1
/.,.,
,/·-·-'
\"'
/
/
r·..J·r·../
/._.I
/
(
1.,--)
Land Use 2004
-Unincorp o ra ted Activity Center
Agriculture
-Community Business
-Commercial Outside o f Centers
-F orest
-Greenbel t/Urban Separator
Indust rial
M in ing
RIii Neighborhood Bus ine ss Center
Rural Neigh borhood
Rura l Residential
-RuralTown
Rural City Urb an Growth Area
-Urban Res id en ti al> 12 du/ac·
Urban Residential 1 du/ac·
Urban Residential 4 -12 d u/ac·
-Urban Plan Developmen t
Kin g County Owned
Open Space/Re creation
Oth er ParksNJilderness
Incorp orated City
L __ J Tri bal Lan ds
~ Urban G rowth Area Boundary
~ ·"·-·~ ,,., ·-·
Forest P roduction District Boundary
Agricultural Prod uc t ion D istrict Boundary
* du -d welling unit, ac = acre
Source : King County Depanment of Devefopm enl and Environmenlal Service s
@, King County
0 2 .5 5 ---------------
N
10 ·+· -
M il e s
October 2004
Chapter Two
Urban Communities
Chapter Two
Urban Communities
The Urban Communities chapter brings together the major elements that combine to make a community
whole: housing, business centers, economic development and human services. By merging these
elements into one chapter, King County emphasizes the importance each plays as part of a livable
community.
The chapter first defines the Urban Growth Area, where most growth will occur, and major land uses
within it. The chapter than provides the framework to guide the development of new urban communities
and redevelopment of existing communities within the unincorporated portion of the Urban Growth Area.
2-1 September 2004
I. Urban land Use
A. Urban Communities
The challenge for King County and its residents is to create urban communities which provide the places
and choices for people and how they want to live, as well as respond to the cultural and economic
diversity of our communities. Urban areas need more than physical infrastructure. They also need a
broad range of amenities and human services that make them attractive and safe places to work and live,
while protecting our physical environment and maintaining the quality of life we all value.
U-101 Development within the Urban Growth Area should create and maintain safe, healthy
and diverse communities. These communities should contain a range of affordable
housing and employment opportunities, school and recreational facilities and
should be designed to protect the natural environment and significant cultural
resources.
1. The Urban Growth Area
The Growth Management Act requires the county to designate an Urban Growth Area where most growth
and development forecasted for King County will be accommodated. By designating an Urban Growth
Area, King County and other counties in the state will:
• Limit sprawling development;
• Reduce costs by encouraging concentrated development;
• Improve the efficiency of human services, utilities and transportation;
• Protect rural areas and resource lands; and
• Enhance open space.
The Urban Growth Area (UGA) for King County is designated on the official Land Use Map adopted with
this plan. The Countywide Planning Policies (CPP) provide the framework which the Metropolitan King
County Council used when adopting the UGA as part of the 1994 Comprehensive Plan.
The UGA includes all cities within the county including the cities in the Rural Area, the cities' annexation
areas, and land within the unincorporated part of the county characterized by urban-type growth. The
UGA also includes the Bear Creek Urban Planned Developments east of Redmond. See Chapter 3,
Rural Legacy and Natural Resource Lands, for additional policy guidance on growth within the rural cities
annexation areas.
King County's total UGA covers 460 square miles, less than one-quarter of the county's total area of
2,134 square miles. Cities comprise most of the land mass of the UGA, at 383 square miles; the
unincorporated portion of the UGA is now about 77 square miles, according to the 2003 King County
Annual Growth Report.
U-102 The Urban Growth Area designations shown on the official Land Use Map includes
enough land to provide the capacity to accommodate growth expected over the
period 2001-2022. These lands should include only those lands that meet the
following criteria.
a. Are characterized by urban development which can be efficiently and cost
effectively served by roads, water, sanitary sewer and storm drainage, schools
and other urban governmental services within the next 20 years;
September 2004 2-2
U-103
b. Do not extend beyond natural boundaries, such as watersheds, which impede
provision of urban services;
c. Respect topographical features which form a natural edge such as rivers and
ridge lines;
d. Are sufficiently free of environmental constraints to be able to support urban
growth without major environmental impacts unless such areas are designated
as an urban separator by interlocal agreement between jurisdictions;
e. Are included within the Bear Creek Urban Planned Development (UPD) sites; and
f. Are not rural land or unincorporated agricultural or forestry lands designated
through the Countywide Planning Policies Plan process.
Parcels which are split by the Urban Growth Area boundary line should be
redesignated to either all urban or all rural unless the parcel is split to recognize
environmentally sensitive features, or the requirements of interlocal agreements or
King County plans.
Some cities that border the Urban Growth Area operate parks in the Rural Area. These parks may have
been acquired by the city through a direct purchase or through a transfer agreement with King County.
Cities can continue to operate parks in the Rural Area consistent with rural development standards. In
specific circumstances, cities can request that these parks be redesignated to urban to allow future
annexation by the city.
U-104 Rural properties that are immediately adjacent to a city and are planned or
designated for park purposes by that city may be redesignated to urban when the
city has committed to designate the property in perpetuity in a form satisfactory to
the King County Council for park purposes and:
a. The property is no more than 30 acres in size and was acquired by the city prior
to 1994; or
b. The property is no more than 30 acres in size and receives county support
through a park or recreation facility transfer agreement between King County
and a city; or
c. The property is or was formerly a King County park and is being or has been
transferred to a city.
U-105 Except for the Blakely Ridge and Redmond Ridge Fully Contained Communities
designations, no new Fully Contained Communities shall be approved in King
County.
2. Growth in Cities and Urban Centers and the Promotion of Public Health
The King County Comprehensive Plan directly affects land use planning decisions only in unincorporated
King County. The cities, however, contain most of the county's economic base and much of its urban
population and provide urban services to adjacent unincorporated areas. In addition, many public
services vital to urban growth are provided to unincorporated areas by independent special purpose
districts. The Countywide Planning Policies guide the development of urban centers, which are located in
cities and should accommodate concentrations of housing and employment. The significant role of the
cities and districts therefore must be recognized in county decision-making and through future planning
efforts.
Focusing development in urban areas can have a positive effect on public health. The percentage of
King County residents who are overweight or obese has risen rapidly since the late 1980s. With obesity
comes increased risk for diabetes, hypertension and heart disease. Evidence suggests one major reason
for rising obesity is the lack of physical activity. Growth patterns in suburban areas, which discourage
walking and promote a reliance on private auto use, have contributed to this public health problem.
2-3 September 2004
Communities that feature many land uses, higher housing density, sidewalks and street connections and
nearby services encourage physical activity such as walking and bicycling.
U-106 Most population and employment growth should locate in the contiguous Urban
Growth Area in western King County, especially in cities and their Potential
Annexation Areas.
U-107 King County supports land use and zoning actions that promote public health by
increasing opportunities for every resident to be more physically active. Land use
and zoning actions include: concentrating growth into the Urban Area, promoting
urban centers, allowing mixed-use developments, and adding pedestrian linkages.
U-108 King County supports the development of Urban Centers to meet the region's needs
for housing, jobs, services, culture and recreation and to promote health. Strategies
may include exploring opportunities for Joint Development or Transit Oriented
Development, siting civic uses in mixed-use areas, and leveraging or utilizing
existing county assets in urban centers.
U-109 King County should concentrate facilities and services within the Urban Growth
Area to make it a desirable place to live and work, to increase the opportunities for
walking and biking within the community, to more efficiently use existing
infrastructure capacity and to reduce the long-term costs of infrastructure
maintenance.
U-11 o King County shall work with cities, especially those designated as urban centers, in
collaborative efforts that result in transfers of density from the Rural Area.
U-111 Development standards for urban areas should emphasize ways to allow maximum
permitted densities and uses of urban land while not compromising the function of
critical environmental areas. Mitigating measures should serve multiple purposes,
such as drainage control, groundwater recharge, stream protection, air quality, open
space preservation, cultural and historic resource protection and landscaping
preservation. When technically feasible, standards should be simple and
measurable, so they can be implemented without lengthy review processes.
3. Urban Growth Area Targets
The Countywide Planning Policies (CPPs) require the county and its cities to plan for future household
and employment growth target ranges for each jurisdiction. In 1994, the Growth Management Planning
Council adopted household and job targets for each jurisdiction to distribute the expected grow1h.
Growth target ranges represent jurisdictions' policy choices regarding the amount of growth they intend to
accommodate. King County and its cities have also developed targets for employment to foster a local
balance between population and employment. The countywide and unincorporated King County's
household growth target and employment targets are contained in the CPPs.
In November 2002, a new set of household and job growth targets were established to guide growth for
the period 2001-2022. Each urban jurisdiction including unincorporated King County was assigned a
growth target based on land capacity and other factors. The complete table of city growth targets,
"Adopted 22-Year Household Growth Targets," is included in this chapter to provide the regional context
for the unincorporated area targets.
U-112 Land use policies and regulations shall accommodate a growth target of
approximately 13,400 households and approximately 7,900 jobs by 2022, established
in the Countywide Planning Policies for the unincorporated portion of the Urban
Growth Area.
September 2004 2-4
U-113
U-114
King County shall provide adequate land capacity for residential, commercial and
industrial growth in the urban unincorporated area. This land capacity shall include
both redevelopment opportunities as well as opportunities for development on
vacant lands.
King County shall use household and employment targets to implement the
comprehensive plan in urban communities. The targets allocated to subareas of
unincorporated King County will be monitored and may be refined through future
planning that includes communities, affected cities and service providers.
The following table, "Household Growth Targets by Sub-region" establishes a breakdown by subarea of
the new unincorporated King County household targets for the Urban Growth Area. The targets in this
table reflect annexations and incorporations that have occurred since the adoption of this plan in 1994.
The table further provides guidance for transfer of portions of growth targets into cities when annexation
takes place in the future. Although they may be relined through future planning with affected
communities and adjacent cities, these ranges are intended to be used as a guide for future planning of
land uses and decisions on services and infrastructure.
2·5 September 2004
HOUSEHOLD GROWTH TARGETS BY SUB-REGION
Unincorporated King County, 2001-2022
Adopted Household Growth Target 2001-2022
Unincorporated King County
Sub-Region Total In designated Outside Cities' Sub-Region
Potential PAAs Targets Totals
Annexation
Areas
East King County 6,801 2,702 4,099 * 40,844 47,645
South King County 4,935 4,343 592 37,420 42,355
Sea-Shore 1,670 0 1,670 54,699 56,369
(North Highline)
Rural Cities ** 0 0 0 .. 5,563 5,563
(Expansion area)
Urban Area Total 13,406 7,045 6,361 138,526 151,932
Rural Area Total 6,000 ... 0 6,000
King County Total 19,406 138,526 157,932
NOTES:
• The 4, 099 target outside East County PAAs consists of the Bear Creek UPD/FCC .
•• Rural-city target numbers include their unincorporated expansion areas .
••• Targets apply to Urban areas only. The rural area does not have a growth target.
Growth in rural areas is forecast to be 6,000 households or 4% of countywide total growth.
Source: Growth Manaaement Plannina Council Motion 02-2, November 2002
September 2004 2-6
-. -·----------
Adopted 22-year Household Growth Targets
King County and its Cities, 2001 -2022
Household Growth Target to be accommodated by local jurisdiction plans and regulations
l.--Between January 2001 and 2022
--------------,
A B C D E ----~--·-----1990 Original 1992-2000 Adopted H'hold PAA H'hold
Jurisdiction
Households 2012 Households Target 2001-2022 Target
Growth Target
Algona 587 404 845 298
----·------AU burn 13,357 8,088 16,108 6,003 815
Beaux Arts 119 0 121 3
Efe11evue
•-----
35,756 8,727 45,836 10,117 178
' '-----
Black Diamond 541 1,624 1,456 1,099
'
Bothell 4,807 1,951 6,401 1,751 584 I
Burien 12,000 1,796 13,399 1,552
Carnation* I 439 404 636 246
Clyde Hill 1.063 12 1.054 21
Covington 3,400 1,493 4,398 1,373
Des Moines 7,054 2.154 11,337 1,576 2 -Duvall* 946 1,661 1,596 1,037
Enumclaw* 2,936 2,425 4,317 1,927
! Federal Way --·-·-j· 25,705 15,239 31,437 6,188 1, 161
Hunts Point 187 4 165 1
Issaquah 3,170 3,380 4,840 3,993 802
Kenmore n.a. n.a. 7,307 2,325
Kent 16,246 9,075 31,113 4,284 546
Kirkland 17,211 5.837 20,736 5,480 747
Lake Forest Park 1,488 451 5,029 538
Maple Valley 2,250 1,539 4,809 300 '
Medina 1,129 17 1,111 31 -------'Mercer Island 8,007 1,122 8,437 1,437
Milton 266 29 339 50 33 -------Newcastle 2,000 833 3,028 863 1
Normandy Park 2,570 135 2,609 100
NOrth Bend* 1,044 1,527 1.841 636 -·-----· Pacific 1,707 1,212 1.992 721 39
Redmond 14,153 11.617 19,102 9,083 390
Renton 18,219 8,960 21,708 6,198 1,739
Sammamish n.a. n.a. 11,131 3,842 I ----
Seattle 236,702 53,877 258,499 51,510
SeaTac
'
9,611 5,525 9,708 4,478 0 I --------· ,,_ ~''''' ' ----------
'Shoreline n.a. 2,559 20,716 2,651
iSkykomish 103 27 104 20
·-------·---------
Snoqualmie * 611 2,784 632 1,697
Tukwila 5,639 5,388 7,186 3,200 8
--
Woodinville 3.000 1,797 3,512 1,869
Yarrow Point ·19 ~·-379 -------------·· -
371 28
-----
City Total:
'
454,400 163.683 584,974 138,526 7.045
Unincorp. KC: I 123,400 33,501 125,942 19,406 6,361
-urban __ -+ ----------'i3,406 -· ·-·I 123,400 26,501 79,042 6,361
·--
6,000 -rural** 38,000 7,000 46,900 n.a. I
Urban Area Total: 57i,800r------------··
151,9:32
-_,, ---
190,184 664,016 n.a.
i King County Total 615,800 197,184 710,916 157,932 n.a.
NOTES: Column D indicates the approximate number of households each jurisdiction is expected to accommodate
during the 22-year period 2001-2022. These growth targets were adopted by the King County Grmvth Management
Planning Council in 2002, and amended in 2004. The targets replace the earlier 1992-2012 numbers which are shown
as Column 8. Column E shows the unincorporated household targets associated with designated Potential Annexation
Areas {PAAs) of selected cities. * Targets of five rural cities include surrounding growth areas. ** Rural-designated
?~~as do no_t ha_~? __ ~t~_rget. The"!"_ are exe_ected to grow b~ no more than 6,000 households durina the 22-vear oeriod.
2-7 September 2004
B. Residential Land Use
Housing is the major use of urban land in King County, occupying well over half of the county's developed
land area. This plan supports the creation of a full range of housing choices for county residents.
U-115 New residential development in the Urban Growth Area should occur where facilities
and services can be provided at the lowest public cost and in a timely fashion. The
Urban Growth Area should have a variety of housing types and prices, including
mobile home parks multifamily development, townhouses and small-lot, single-
family development.
1. Residential Densities
The density of eight homes per acre expressed below is a long-term goal and would be an average
density of single-family and multifamily developments. Single-family homes will continue to account for
most of the land area used for new development in the county. This plan proposes ways to develop
single-family homes more efficiently so that urban land is used more efficiently, homes are affordable,
more housing choices are available and densities are adequate to allow for transit services. Housing at
higher densities can promote public health by creating urban communities that support public
transportation and nearby services and thereby increase opportunities for walking or biking.
U-116 King County shall seek to achieve through future planning efforts over the next
twenty years, an average zoning density of at least seven to eight homes per acre in
the Urban Growth Area through a mix. of densities and housing types. A lower
density zone may be used to recognize existing subdivisions with little or no
opportunity for infill or redevelopment.
U-117 King County should apply the urban residential, low land use designation: to protect
floodplains, critical aquifer recharge areas, high function wetlands and unstable
slopes from degradation, and link these environmental features into a network of
open space, fish and wildlife habitat and urban separators. The residential density
for land so designated should be maintained at one unit per acre, provided that
lands that are sending sites under the Transfer of Density Program may transfer
density at a rate of at least four units per acre.
U-118 Multifamily housing in the Urban Growth Area should be sited as follows:
a. In or next to unincorporated activity centers or next to community or
neighborhood business centers;
b. In mixed-use developments in centers and activity areas; and
c. On small, scattered parcels integrated into existing urban residential areas. New
multifamily housing should be built to the scale and design of the existing
community or neighborhood, while contributing to an area-wide density that
supports transit and allows for a range of housing choices. Over time, zoning
should encourage a larger proportion of multifamily housing to be located on
small scattered sites rather than on larger sites.
U-119 Land zoned for multifamily uses should be converted to nonresidential zone
categories only after new multifamily sites are identified and rezoned to replace the
multifamily housing capacity lost due to the conversion.
2. Minimum Density
In accordance with Countywide Planning Policy LU-66(b), King County has included a minimum density
requirement in its zoning regulations for all new urban residential development with a zoned density of
four or more homes per acre.
September 2004 2-8
U-120 King County should apply minimum density requirements to all urban residential
zones of four or more homes per acre, except under limited circumstances such as
the:
a. Presence of significant physical constraints, or
b. Implementation of standards applied to a property through a property-specific
development condition, special district overlay, or subarea plan.
3. Increases of Zoning Density
While King County supports higher densities in the urban areas, increased densities that would be
incompatible with existing neighborhoods or cause significant impacts on roads, services and the
environment are discouraged. The following policies will guide decisions on application of densities and
proposed rezones.
U-121
U-122
U-123
U-124
U-125
Requests for increases in density of urban residential property zoned for one
dwelling unit per acre must include a demonstration that the property does not meet
the criteria of Policy U-117.
King County shall not approve proposed zoning changes to increase density within
the Urban Area unless:
a. The development will be compatible with the character and scale of the
surrounding neighborhood;
b. Urban public facilities and services are adequate, consistent with adopted levels
of service and meet GMA concurrency requirements, including King County
transportation concurrency standards;
c. The proposed density change will not increase unmitigated adverse impacts on
environmentally sensitive areas, either on site or in the vicinity of the proposed
development;
d. The proposed density increase will be consistent with or contribute to achieving
the goals and policies of this comprehensive plan, and subarea plan, if
applicable; and
e. The proposal is consistent with the adopted city comprehensive plan for the
Potential Annexation Area where the rezone is located if the proposed density
exceeds eight dwelling units per acre. If the city is not planning for urban
densities and efficient land use patterns consistent with the Countywide
Planning Policies, then this paragraph shall not apply.
King County, when evaluating rezone requests for increases in density, shall notify
adjacent cities, special purpose districts and local providers of urban utility services
and should work with these service providers on issues raised by the proposal.
King County supports increases in urban residential density through a rezone or a
proposal to increase density through the density transfer or density incentive
programs when the proposal will help resolve traffic, sewer, water, parks or open
space deficiencies in the immediate neighborhood or will help promote physical
activity by providing trail linkages and connections to services.
King County shall not support requests for residential density increases on lands
located within the outer boundaries of the Noise Remedy Area as identified by
Seattle-Tacoma International Airport.
Development in the Urban Growth Area at a higher density than normally permitted by zoning will be
allowed in exchange or public amenities such as low-income housing, preservation or designated historic
features or extra energy conservation measures, or through the transfer of density credits from other
parts of the county.
2·9 September 2004
U-126 Density incentives should encourage private developers to provide innovative
affordable housing, significant open space, trails and parks; to locate close to
transit; to participate in historic preservation; and to include energy conservation
measures exceeding state requirements.
4. Mixed-Used Development
Mixed-use development combines higher density residential units with retail or office uses in the same
building or within an integrated development on the same lot. Quality mixed-use developments can
provide convenient shopping and services to both residents of the development and those who live near
by. They can help to build a sense of community, as neighboring merchants and residents get to know
each other. Mixed use is traditional in older downtowns and commercial areas, where offices and retail
typically occupy the first floor and residences are upstairs. Mixed-use developments can promote public
health by providing opportunities for people to walk or bicycle to retail and public services. People are
more likely to walk to their destination if the distance is less than one-half mile or to bike if the distance is
less than two miles.
U-127 King County supports mixed-use developments in community and neighborhood
business centers, the White Center Unincorporated Activity Center, and in areas
designated commercial outside of centers.
U-128 Design features of mixed-use developments should include the following:
a. Integration of the retail and/or office uses and residential units within the same
building or on the same parcel;
b. Ground level spaces built to accommodate retail and office uses;
c. Off-street parking behind or to the side of the buildings, or enclosed within
buildings; and
d. Opportunities to have safe, accessible pedestrian connections and bicycle
facilities within the development and to adjacent residential developments.
U-129 In a mixed-use development where residential and nonresidential uses are proposed
in separate structures and the residential uses are proposed to be constructed prior
to the nonresidential uses, the initial review of the development should be through a
process that ensures an integrated design.
U-130 In a mixed-use development, incentives such as increases in residential density or
floor area ratio should be used to encourage the inclusion of public gathering
spaces in the site design.
5. Urban Residential Neighborhood Design and Infill/Redevelopment
King County residents can enjoy their urban neighborhoods both for their unique character and for the
amenities they provide. Outdoor spaces need to be usable, attractive, comfortable, and enjoyable. The
design of urban streets, including features such as parking strips, street trees, alleys and off-street
parking all contribute to the character of urban neighborhoods. Careful site planning can incorporate
neighborhood features, contribute to aesthetic value, minimize site disturbance, conserve energy and, in
some cases, reduce development costs. Neighborhood shopping, libraries, larger parks, high schools
and public golf courses are examples of uses that provide amenities for nearby residents. Small retail
establishments integrated into residential development (e.g., a laundromat or video rental store) can
provide convenient services and help residents reduce automobile trips. Urban areas that are interesting
and safe for pedestrians and bicyclists, and that provide many necessary services close to residential
developments, can promote public health by increasing opportunities for physical activity during a normal
day's activities.
September 2004 2-10
•
U-131
U-132
U-133
U-134
U-135
U-136
U-137
King County encourages innovative, quality infill development and redevelopment in
existing urban areas. A variety of regulatory, incentive and program strategies could
be considered, including:
a. Special development standards for infill sites;
b. Assembly and resale of sites to providers of affordable housing;
c. Impact mitigation fee structures that favor infill developments;
d. Greater regulatory flexibility in allowing standards to be met using innovative
techniques; and
e. Joint public/private loan guarantee pools.
Single-family detached homes, townhomes, duplexes and apartments shall be
allowed in all urban residential zones, provided that:
a. Apartments shall not be allowed in the R-1 zone unless fifty percent or more of
the site is environmentally constrained; and
b. Apartments in R-1, R-4, R-6 and R-8 shall not be developed at densities in excess
of 18 units per acre in the net buildable area.
Urban residential neighborhood design should preserve historic and natural
characteristics and neighborhood identity, while providing privacy, community
space, and safety and mobility for pedestrians and bicyclists.
Site planning tools, such as clustering, shall be permitted in order to allow
preservation or utilization of unique natural features within a development.
New urban residential developments should provide recreation space, community
facilities and neighborhood circulation for pedestrians and bicyclists to increase
opportunities for physical activity.
Residential developments should provide a variety of housing types and lot patterns
through lot clustering, flexible setback requirements and mixed attached and
detached housing.
Nonresidential uses, such as schools, religious facilities, libraries and small-scale
retail and personal services should be integrated into urban residential
neighborhoods to create viable neighborhoods with reduced dependence on the
automobile. These uses should be sited, designed and scaled to be compatible with
existing residential character and should provide convenient walking and bicycling
connections to neighboring residences.
Multifamily residential development is important to King County's housing supply because it uses land
and energy efficiently and provides opportunities for affordable rental and ownership housing. Multifamily
development is defined as one building that contains two or more separate dwelling units. Multifamily
developments can be apartments, duplexes, or townhouses.
U-138 Multifamily residential development should provide common and private open
space, variation in facades and other building design features which may include
varying window treatments, building colors and materials, and light fixtures that will
give a residential scale and identity to multifamily development.
Generally, larger parcels of buildable vacant land in the Urban Growth Area have been preferred for
development. Development of these large parcels, especially for attached units at higher densities. often
provoked concerns about compatibility due to their scale and design.
As larger vacant lots become increasingly scares, attention will turn more and more towards smaller
vacant lots often located within built neighborhoods (i.e., infill) and to redevelopment. Residential
development proposals on small lots and redevelopment often can be an unobtrusive and desirable
2-11 September 2004
ns of increasing density within existing neighborhoods. Infill development and redevelopment are
necessary to achieve growth management objectives such as maximizing the efficient use of land and
increasing the variety of housing choices and prices.
U-139 King County should support infill and redevelopment proposals that serve to
improve the overall character of existing communities or neighborhoods.
6. Residential Site Improvement Standards and Public Services
The following policies govern King County land use regulations and functional plans that contain
improvement standards for the review of proposed rezones, residential subdivisions, short subdivisions,
multifamily buildings and construction permits.
U-140
U-141
Residential developments within the Urban Growth Area, including mobile home
parks, shall provide the following improvements:
a. Paved streets (and alleys if appropriate), curbs and sidewalks, and internal
walkways when appropriate;
b. Adequate parking and consideration of access to bus service and passenger
facilities;
c. Street lighting and street trees;
d. Stormwater control;
e. Public water supply;
f. Public sewers; and
g. Landscaping around the perimeter and parking areas of multifamily
developments.
Common facilities such as recreation space, internal walkways that provide inter-
and intra-connectivity, roads, parking, solid waste and recycling areas should be
included in multifamily developments.
Neighborhood recreation space and parks are important amenities for residents. The higher the density,
the more essential such amenities become to a desirable living environment. If the site of a proposed
development is large enough, a park site dedication or private park site can be required as a condition of
a rezone, subdivision or site plan approval.
U-142 Recreation space based on the size of the developments shall be provided on site,
except that in limited cases, fee payments for local level park and outdoor recreation
needs may be accepted by King County.
U-143 Recreation spaces located within a residential development, except those for elderly
or other special needs populations, shall include a child's play area.
U-144 Recreation spaces located in residential developments in the Urban Area should
include amenities such as play equipment, open grassy areas, barbecues, benches,
trails and picnic tables.
C. Commercial Land Use
The Countywide Planning Policies call for a significant share of new jobs and housing to occur within
cities and in urban centers, which are areas of concentrated employment and housing. The designated
urban centers are to accommodate 15,000 jobs within a one-half-mile radius of a major transit stop, an
average employment density of 50 jobs per gross acre and an average of 15 housing units per gross
acre. All of the urban centers are in cities.
In addition to the urban centers, cities and unincorporated urban King County have existing intensive
industrial, commercial and residential areas that will continue to grow and provide employment, services,
September 2004 2-12
shopping and housing opportunities, but not at the same level as urban centers. Three categories of
centers are established for urban unincorporated areas of King County. Higher density, more-
concentrated developed industrial and commercial areas are classified as unincorporated activity centers.
Midrange centers are called community business centers and smaller, local centers are called
neighborhood business centers. The locations of these centers are shown on the Urban Centers map at
the end of this chapter. This plan also recognizes existing commercial and industrial development that is
outside of unincorporated activity centers, community business centers and neighborhood business
centers.
U-145
U-146
Business/office park developments should be located in or adjacent to an
unincorporated activity center. They may serve as a transition between office/retail
areas and residential areas. They should be designed to take advantage of on-site or
nearby structured parking and/or bus service and passenger facilities should be
compatible with the objective of higher employment densities.
New commercial and office development shall locate in designated unincorporated
activity centers, community and neighborhood business centers, and in areas
designated commercial outside of centers.
Warehouse-style retail businesses, large retail complexes, stadiums, large churches and colleges are
examples of land uses that serve as destinations from throughout the region. Such uses require a full
range of urban services including transit, substantial parking, and access to arterials and freeways, and
therefore should locate in the urban area where these services are available. In addition, these land uses
have traffic and impervious surface impacts that are inappropriate for the Rural Area.
U-147 New facilities and businesses that draw from throughout the region, such as large
retail uses, large public assembly facilities and institution of higher education
should locate in the Urban Area.
1. Unincorporated Activity Centers
Unincorporated activity centers are the primary locations for commercial and industrial development in
urban unincorporated King County. Currently, White Center is the only designated unincorporated activity
center, as other such centers are now parts of cities. The White Center Community Action Plan
establishes the size and mix of uses allowed in the White Center Unincorporated Activity Center.
U-148
U-149
U-150
Unincorporated activity centers in urban areas should provide employment, housing,
shopping, services and leisure-time amenities to meet the needs of the regional
economy. The mix of uses may include:
a. Health, human service and public safety facilities;
b. Retail stores and services;
c. Professional offices;
d. Business/office parks;
e. Multifamily housing and mixed-use developments;
f. Heavy commercial and industrial uses, when there is direct freeway or rail
access;
g. Light manufacturing; and
h. Parks and open space.
Within unincorporated activity centers, the following zoning is appropriate: Urban
Residential with a density of twelve to forty-eight dwelling units per acre; Regional
Business; Community Business; Neighborhood Business; Office and Industrial.
King County may designate new unincorporated activity centers or expand existing
unincorporated activity centers only through a subarea planning process which : ·
should address:
2-13 September 2004
U-151
U-152
U-153
U-154
U-155
a. The relationship of the entire center to its surrounding uses;
b. Availability of supporting public services;
c. The function of the center to other centers in the sub-region;
d. The need for additional commercial and industrial development;
e. The size and boundaries of the center; and
f. Zoning.
The size, uses and boundaries of unincorporated activity centers should be
consistent with the following criteria:
a. More than forty acres in size, excluding land needed for surface water
management or protection of environmentally sensitive areas;
b. Retail space based on the amount of residential development planned for the
surrounding area to provide for community and regional shopping needs; and
c. Retail space should not exceed sixty acres and 600,000 square feet unless it is
served by direct freeway access by a principal or minor arterial and is well
served by transit.
Design features of unincorporated activity centers should include the following:
a. Safe and attractive walkways and bicycle lanes with access to each major
destination including schools, community centers and commercial areas;
b. Buildings close to sidewalks to promote walking and access to transit;
c. Compact design with close grouping of compatible uses;
d. Off-street parking in multistory structures located to the side or rear of buildings
or underground;
e. Public art;
f. Public spaces, such as plazas and building atriums;
g. Retention of attractive natural features, historic buildings and established
character;
h. Aesthetic design and compatibility with adjacent uses through setbacks,
building orientation, landscaping and traffic control;
i. Screening of unsightly views, such as heavy machinery, outdoor storage areas,
loading docks and parking areas from the view of adjacent uses and from
arterials; and
j. Signs should be regulated to reduce glare and other adverse visual impacts on
nearby residences, without limiting their potential contribution to the color and
character of the center.
Development within the designated White Center Unincorporated Activity Center, as
shown on the Comprehensive Plan Land Use Map, shall be in accordance with the
White Center Community Action Plan.
The White Center Community Action Plan establishes the following zoning as
appropriate within the White Center Unincorporated Activity Center: Urban
Residential with a density of twelve to forty-eight dwelling units per acre,
Neighborhood Business, Community Business, Office and Industrial.
In the White Center Unincorporated Activity Center, existing Industrial uses should
be zoned and regulated to preserve their use into the future. Conversion of
industrial properties to other uses shall be strictly limited.
White Center was selected as one of three case study areas for further study as part of the King County
Land Use Transportation Air Quality and Health project. Information from the study will show which types
of changes in the urban form of the area or in the transportation system will lead to an increase in public
health. These results should be used to guide development in the White Center area and to prioritize
capital expenditures. Additionally, the redevelopment of Park Lake Homes was selected as a
demonstration project for low-impact development in the county.
Septernbe r 2004 2·14
U-156 In the White Center Unincorporated Activity Center, new major residential
developments should include low-impact design features and should promote public
health by increasing opportunities for physical activity in daily life. The development
should include: safe walkways and bicycle lanes with access to commercial areas,
schools, and community facilities; trails; and pocket parks.
2. Community Business Centers
Community business centers are primarily retail developments designed to serve a nearby market area of
15,000 to 40,000 people. Community business centers should be sited so they do not adversely affect
other centers and are easily accessible by automobile or public transportation. Community business
centers should be designed to be compatible with adjacent residential uses, and should promote
pedestrian and bicycle access.
U-157
U-158
U-159
U-160
U-161
Community business centers in the urban areas should provide primarily shopping
and personal services for nearby residents. Offices and multifamily housing are also
encouraged. Industrial and heavy commercial uses should be excluded.
Community business centers should include the following mix of uses:
a. Retail stores and services;
b. Professional offices;
c. Community and human services; and
d. Multifamily housing as part of a mixed-use development, with residential
densities of 12 to 48 units per acre when well served by transit.
Designated community business centers are shown on the Comprehensive Plan
Land Use Map. Expansion of existing or designation of new community business
centers shall be permitted only through a subarea planning process.
Redevelopment of existing community business centers is encouraged.
Within community business centers, the following zoning is appropriate:
Neighborhood Business, Community Business and Office.
The specific size and boundaries of community business centers should be
consistent with the criteria listed below.
a. More than ten acres and up to 40 acres in size, excluding land needed for
surface water management or protection of environmentally sensitive areas;
b. Designed to provide shopping and services for a market population of 15,000 to
40,000 people;
c. Located one to three miles from an unincorporated activity center or from
another community business center. May be located less than two miles from a
neighborhood business center when it is demonstrated the neighborhood
business center will not be adversely affected; and
d. Must be located at the intersection of two principal or minor arterials.
Design features of community business centers should include the following:
a. Safe and attractive walkways and bicycle lanes;
b. Close grouping of stores;
c. Off-street parking behind or to the side of buildings, or enclosed within
buildings;
d. Public art; and
e. Retention of attractive natural features, historic buildings and established
character.
2-15 September 2004
3. Neighborhood Business Centers
Neighborhood business centers are shopping areas offering convenience goods and services to local
residents. Neighborhood business centers are intended to be small and compatible with adjacent
residential areas and often are used on the way to another destination (for example, a fuel stop before or
after commuting). Sometimes they consist of only one use or business. Neighborhood business centers
should be designed to promote pedestrian and bicycle access.
U-162 Neighborhood business centers in urban areas should include primarily retail stores
and offices designed to provide convenient shopping and other services for nearby
residents. Industrial and heavy commercial uses should be excluded.
Neighborhood business centers should include the following mix of uses:
a. Retail stores and services;
b. Professional offices; and
c. Multifamily housing as part of a mixed-use development with residential
densities up to 12 units per acre when convenient to a minor arterial. Higher
densities of 12 to 18 units per acre are appropriate when the cen'ter is convenient
to a principal arterial.
U-163 Designated neighborhood business centers are shown on the Comprehensive Plan
Land Use Map. Expansion of existing or the designation of new neighborhood
business centers shall only be permitted through a subarea planning process.
Redevelopment of existing Neighborhood neighborhood business centers is
encouraged.
U-164 Within neighborhood business centers, the following zoning is appropriate:
Neighborhood Business and Office.
U-165 The specific size and boundaries of neighborhood business centers should be
consistent with the criteria listed below.
a. Ten acres or less in size, excluding land needed for surface water management
or protection of environmentally sensitive features;
b. Designed to provide convenience shopping for a market population of 8,000 to
15,000 people;
c. Located on a minor arterial with adequate traffic capacity;
d. Serviced by intersections free of traffic congestion caused by topography or
poor road design; and
e. Located one to three miles from another neighborhood business center.
U-166 Design features of neighborhood business centers should include the following:
a. Safe and attractive walkways and bicycle lanes;
b. Close grouping of stores;
c. Off-street parking behind or to the side of buildings, or enclosed within
buildings;
d. Public art;
e. Retention of attractive natural features, historic buildings or established
character;
f. Landscaping, which may include planters and street trees;
g. Appropriate signage;
h. Public seating areas; and
i. Architectural features which provide variation between buildings or contiguous
storefronts.
September 2004 2-16
4. Commercial Development Outside of Centers
The Commercial Outside of center (CO) Land Use designation recognizes commercial uses predating this
plan that were located outside a designated center. The CO designation is also appropriate as a
transitional designation within certain potential annexation areas. In these areas, the county will utilize
the memorandum of understanding and applicable comprehensive plan policies to determine the
appropriate zoning to implement this transitional designation.
U-167 Stand-alone commercial developments legally established outside designated
centers in the Urban Growth Area may be recognized with the CO designation and
appropriate commercial zoning. When more detailed subarea plans are prepared,
these developments may be designated as centers and allowed to grow if
appropriate, or may be encouraged to redevelop consistent with the residential
density and design policies of the comprehensive plan.
U-168 The CO designation may be applied as a transitional designation in Potential
Annexation Areas identified in a signed memorandum of understanding between a
city and the county for areas with a mix of urban uses and zoning in order to
facilitate the joint planning effort directed by the memorandum of understanding.
Zoning to implement this transitional designation should recognize the mix of
existing and planned uses. No zone changes to these properties to allow other
nonresidential uses, or zone changes to allow expansion of existing nonresidential
uses onto other properties, should occur unless or until a subarea planning process
with the city is completed.
5. Commercial Site Improvement Standards and Public Services
The following policy governs King County land use regulations and functional plans that contain
improvement standards for the review of proposed rezones and commercial construction permits.
U-169 Commercial, retail and industrial developments should foster community, create
enjoyable outdoor areas and balance needs of automobile movement with
pedestrian and bicycle mobility and comfort. Commercial and industrial
developments shall provide the following improvements:
a. Paved streets;
b. Sidewalks and bicycle lanes in commercial and retail areas;
c. Adequate parking for employees and business users;
d. Landscaping along or within streets, sidewalks and parking areas to provide an
attractive appearance;
e. Adequate stormwater control, including curbs, gutters and stormwater retention
facilities;
f. Public water supply;
g. Public sewers; and
h. Controlled traffic access to arterials and intersections.
6. Industrial Development
Maintaining a strong industrial land supply is an important factor in maintaining the county's economic
base and providing family wage jobs. The following policies assure that industrial development is
compatible with adjacent land uses while providing appropriate services for employees. In addition, King
County is committed to helping return contaminated sites to productive use.
U-170 Within the UGA but outside unincorporated activity centers, properties with existing
industrial uses shall be protected. The county 1J1ay use tools such as special district
overlays to identify them for property owners and residents of surrounding
neighborhoods.
2·17 September 2004
U-171 Industrial development should have direct access from arterials or freeways.
Access points should be combined and limited in number to allow smooth traffic
flow on arterials. Access through residential areas should be avoided.
U-172 Small amounts of retail and service uses in industrial areas may be allowed for
convenience to employees and users.
U-173 King County, in collaboration with cities and the development community, should
create and fund a process to clean up and reclaim polluted industrial areas in order
to expand the land available for industrial development.
D. Urban Planned Developments (UPDs) and Fully Contained Communities
(FCCs)
Within the designated UGA, development of large land ownerships may offer the public and the property
owner opportunities to realize mutual benefits when such development is coordinated through the review
process as an Urban Planned Development (UPD). Possible public benefits include greater preservation
of public open space, proponent contributions to major capital improvement needs, diversity in housing
types and affordability, and the establishment of the specific range and intensity of uses for the entire
U_rban Planned Development. A property owner and the public could benefit from the efficiency of
combined hearings and land use decision making, as well as the establishment of comprehensive and
consistently applied project-wide mitigations guiding the review of subsequent land use approvals.
U-174
U-175
Sites for potential Urban Planned Developments (UPDs) may be designated within
the established Urban Growth Area to realize mutual benefits for the public and the
property owner. Two UPD areas have been designated by the county: the Bear
Creek UPD area, comprised of Redmond Ridge (formerly known as Northridge) UPD,
Trilogy at Redmond Ridge (formerly known as Blakely Ridge) UPD, and the proposed
Redmond Ridge East UPD; and Cougar Mountain Village UPD. Future UPD sites in
the Urban Growth Area shall be designated through a subarea planning process, or
through a comprehensive plan amendment initiated by the property owner.
The creation of Urban Planned Developments (UPDs) is intended to serve as a model
for achieving a mix of uses, appropriate development patterns, and high quality
design as well as providing for public benefits which shall include:
a. Open space and critical areas protection;
b. Diversity in housing types and affordability;
c. Quality site design; and
d. Transit and nonmotorized transportation opportunities.
The Bear Creek UPD area was first designated for urban development in 1989 in the Bear Creek
Community Plan. The urban designation of this area under the GMA was established in the Countywide
Planning Policies in 1992 and affirmed in 1994. The Bear Creek UPD area was included in the Urban
Growth Area designated in the 1994 King County Comprehensive Plan. Since the adoption of the 1994
Comprehensive Plan, both Redmond Ridge and Trilogy have been approved as Urban Planned
Developments and King County has entered into development agreements governing the development of
these sites. The legality of these development approvals was challenged and these legal challenges
have been rejected. Therefore, these sites will be, and are being, developed at urban densities.
Through the adoption of the King County Comprehensive Plan 2000 Update, King County reaffirmed its
urban designation of the Bear Creek UPD area. In addition to the reasons that led the county (and the
region) to originally include this area within the county's UGA, when the county adopted the 2000 update,
it noted that: two sites within this area had been approved for urban development after the adoption of
the original GMA comprehensive plan; significant infrastructure improvements had been made at these
September 2004 2-18
sites: and the ultimate development of these sites was proceeding in accordance with issued permit
approvals. The existence of these urban improvements further supported a conclusion that this area is
characterized by urban growth within the meaning of the GMA and was therefore appropriately included
within the county's UGA.
Since the county considered and adopted the 2000 update, significant development within the Bear Creek
UPD area has taken place. The UPD permits approved by the county required the construction of
infrastructure needed to support urban development of the Bear Creek UPD area. Those infrastructure
improvements have now been completed or are under construction. This includes sanitary sewer trunk
lines and pump stations; water trunk lines, pump stations, and storage facilities; stormwater collection,
detention, treatment and discharge facilities; other utilities; a park and open space system linked by trails;
and required road improvements. In addition, King County has granted final plat approval for lots for
more than 2,100 of the dwelling units approved by the Redmond Ridge and Trilogy U PD permits and
more than 1,600 of those dwelling units have been built, are under construction, or have been permitted.
Furthermore, major community facilities and services such as the 18-hole golf course and clubhouse, the
Redmond Ridge Community Center, and the retail center and grocery store have been completed or are
under construction. All of these developments support the conclusion that the Redmond Ridge and
Trilogy UPD sites are now fully characterized by and irrevocably committed to urban growth, and the
county therefore reaffirms its urban designation of the Bear Creek UPD area.
The urban designation of the Bear Creek area includes one portion of the original urban area that has not
yet been approved for development. However, this area, now referred to as Redmond Ridge East, is the
subject of pending applications for approval of a UPD permit and an FCC permit. Those permits would
authorize the urban development of Redmond Ridge East. Redmond Ridge East would be served by the
urban infrastructure that has already been constructed to serve the Redmond Ridge and Trilogy UPD
sites. The county reaffirms its urban designation of the Redmond Ridge East for the following reasons:
this site has always been treated by King County as part of the Bear Creek UPD urban area; this site is
adjacent to the urban development that has already occurred and that will continue to occur at Trilogy and
Redmond Ridge; this site is located in relationship to the rest of the Bear Creek UPD area so as to be
appropriate for urban growth; and this site is an area that will be served by existing urban public facilities
and services that have been provided in accordance with Trilogy and Redmond Ridge UPD permit
requirements.
The Growth Management Act allows counties to establish a process, as part of the UGA designation, for
reviewing proposals to authorize new Fully Contained Communities (FCC). Criteria for approval of FCCs
are contained in RCW 36.?0A.350. If a county establishes in its comprehensive plan a process for
authorizing FCCs, it must adopt procedures for approving FCCs in its development regulations. King
County has established a new fully contained community, consisting of the Bear Creek UPD area.
U-176
U-177
U-178
King County has established a new Fully Contained Community. One area is
designated through this plan shown on the Land Use Map as a Fully Contained
Community: the Bear Creek UPD area comprised of Trilogy at Redmond Ridge,
Redmond Ridge, and Redmond Ridge East Urban Planned Development sites.
Nothing in these policies shall affect the continued validity of the approved Urban
Planned Development permits for either of these sites. This FCC designation may be
implemented by separate or coordinated FCC permits.
The population, household, and employment growth targets and allocations for the
county's UGA in this plan include the Bear Creek UPD area. Accordingly, the
requirements in RCW 36.?0A.350(2) that the county reserve a portion of the 20-year
population projection for allocation to new Fully Contained Communities has been
satisfied.
The review and approval process for a Fully Contained Community (FCC) permit
shall be the same as that for an Urban Planned Development (UPD) permit, except
the following additional criteria shall be met, pursuant to the provisions of RCW
2-19 September 2004
September 2004
36.70A.350:
a. New infrastructure (including transportation and utilities infrastructure) is
provided for and impact fees are established and imposed on the FCC
consistent with the requirements of RCW 82.02.050;
b. Transit-oriented site planning and traffic demand management programs are
implemented in the FCC. Pedestrian, bicycle, and high occupancy vehicle
facilities are given high priority in design and management of the FCC;
c. Buffers are provided between the FCC and adjacent non-FCC areas. Perimeter
buffers located within the perimeter boundaries of the FCC delineated
boundaries, consisting of either landscaped areas with native vegetation or
natural areas, shall be provided and maintained to reduce impacts on adjacent
lands;
d. A mix of uses is provided to offer jobs, housing, and services to the residents of
the new FCC. No particular percentage formula for the mix of uses should be
required. Instead, the mix of uses for a FCC should be evaluated on a case-by-
case basis, in light of the geography, market demand area, demographics,
transportation patterns, and other relevant factors affecting the proposed FCC.
Service uses in the FCC may also serve residents outside the FCC, where
appropriate;
e. Affordable housing is provided within the new FCC for a broad range of income
levels, including housing affordable by households with income levels below
and near the medium income for King County.
f. Environmental protection has been addressed and provided for in the new FCC,
at levels at least equivalent to those imposed by adopted King County
environmental regulations;
g. Development regulations are established to ensure urban grown will not occur in
adjacent nonurban areas. Such regulations shall include but are not limited to
rural zoning of adjacent rural areas, FCC permit conditions requiring sizing of
FCC water and sewer systems so as to ensure urban growth will not occur in
adjacent nonurban areas; and/or FCC permit conditions prohibiting connection
by property owners in the adjacent Rural Area (except public school sites) to the
FCC sewer and water mains or lines;
h. Provision is made to mitigate impacts of the FCC on designated agricultural
lands, forest lands, and mineral resource lands; and
i. The plan for the new FCC is consistent with the development regulations
established for the protection of critical areas by King County pursuant to RCW
36.70A.170.
For purposes of evaluating a FCC permit the following direction is provided: The
term "fully contained" is not intended to prohibit all interaction between a FCC and
adjacent lands but to limit impacts on adjacent lands and contain them within the
development site as much as possible. "Fully contained" should be achieved
through the imposition of development conditions that limit impacts on adjacent and
nearby lands and do not increase pressures on adjacent lands for urban
development. "Fully contained" is not intended to mandate that all utilities and
public service needed by an urban population both start and end within the property
(since sewer, water, power, and roads, are of such a nature that the origin and/or
outfall cannot reasonable both exist within the property boundaries), but that the
costs and provisions for those utilities and public services that are generated
primarily by the FCC (schools, police, parks, employment, retail needs) be
reasonably accommodated within its boundaries and not increase pressure for more
urban development on adjacent properties.
2-20
E. Urban Separators and the Four-to-One Program
The Countywide Planning Policies call for the county and cities to implement urban separators. Different
from the Rural Area and Natural Resource Lands, these are low-density areas within the Urban Growth
Area that create open space corridors, provide a visual contrast to continuous development and reinforce
the unique identities of communities. Urban separators can play a significant role in preserving
environmentally sensitive areas and in providing habitat for fish and wildlife. They also provide
recreational benefits, such as parks and trails, and meet the Growth Management Act's requirement for
greenbelts and open space in the Urban Growth Area. Urban Separators are mapped on the Land Use
2004 map in Chapter 1.
U-179
U-180
U-181
Urban separators are corridors of land that define community or municipal identities
and boundaries, provide visual breaks in the urban landscape, and link parks and
open space within and outside the Urban Growth Area. These urban corridors
should include and link parks and other lands that contain significant
environmentally sensitive features, provide wildlife habitat or critical resource
protection, contain defining physical features, or contain historic resources. The
residential density for land so designated should be maintained at one unit per acre,
provided that lands that are sending sites under the Transfer of Density Program my
transfer density at a rate of at least four units per acre.
King County should actively pursue designating urban separators in the
unincorporated area and work with the cities to establish permanent urban
separators within the unincorporated area that link with and enhance King County's
urban separator corridors.
Designated urban separators should be preserved through park, trail and open
space acquisitions, incentive programs such as the Transfer of Development Credit
program, the Public Benefit Rating System program and regulatory measures.
While urban separators complement the regional open space system by helping to define urban
communities, the King County Four-to-One Program provides an opportunity to add land to the regional
open space system through the dedication of permanent open space. The purpose of the program is to
create a contiguous band of open space, running north and south along the main Urban Growth Area
Boundary. Changes to the UGA through this program are processed as Land Use Amendments to the
King County Comprehensive Plan, subject to the provisions in K.C.C. chapter 20.18.
U-182
U-183
U-184
King County shall actively pursue dedication of open space north and south along
the Urban Growth Area line through the Four-to-One Program. Through this
program, one acre of Rural Area land may be added to the Urban Growth Area in
exchange for a dedication to King County of four acres of permanent open space.
King County shall evaluate Four-to-One proposals for both quality of open space
and feasibility of urban development. The highest-quality proposals shall be
recommended for adoption as amendments to the Urban Growth Area. Lands
preserved as open space shall retain their rural area designations and should
generally be configured in such a way as to connect with open space on adjacent
properties.
King County shall use the following criteria for evaluating open space in Four-to-One
proposals:
a. Quality of fish and wildlife habitat areas;
b. Connections to regional open space systems;
c. Protection of wetlands, stream corridors, ground water and water bodies;
d. Unique natural, biological, cultural, historical, or archeological features; and
2-21 September 2004
e. Size of proposed open space dedication and connection to other open space
dedications along the Urban Growth Area line.
U-185 King County shall preserve the open space acquired through this program primarily
as natural areas, passive recreation sites or resource lands for farming or forestry.
King County may allow the following additional uses only if located on a small
portion of the open space, provided that these uses are found to be compatible with
the site's natural open space values and functions such as those listed in the
preceding policy;
a. Trails;
b. Natural-appearing stormwater facilities;
c. Compensatory mitigation of wetland losses on the urban designated portion of
the project, consistent with the King County Comprehensive Plan and the
Sensitive Area Ordinance; and
d. Active recreation uses not to exceed five percent of the total open space area.
Support services and facilities for the active recreation uses may locate within
the active recreation area only, and shall not exceed five permit of the active
recreation area. An active recreation area shall not be used to satisfy the active
recreation requirements for the urban designated portion of the project as
required by K.C.C. Title 21 A.
U-186 Land added to the Urban Growth Area under this policy shall meet the density
requirements, shall be physically contiguous to the existing Urban Growth Area and
shall be able to be served by sewers and other efficient urban services and facilities.
In some cases, lands must meet affordable housing requirements under this
program. The total area added to the Urban Growth Area as a result of this policy
shall not exceed 4,000 acres.
U-187 King County shall amend the Urban Growth Area to add rural lands to the UGA
consistent with Policy U-182 during the annual comprehensive plan amendment
process. Open space dedication shall occur at final formal plat recording. If the
applicant decides not to pursue urban development or fails to record the final plat
prior to expiration of preliminary plat approval, the urban properties shall be
restored to a rural designation during the next annual review of the King County
Comprehensive Plan.
September 2004 2·22
II. Po.tential Annexation Areas
There are 216,000 people living in urban unincorporated King County, as reported in the 2003 Annual
Growth Report. This population is equivalent to the second largest city in the state. The land base in
these areas is primarily residential, with limited amounts of commercial and retail development. Much of
the urban unincorporated area is made up of geographically isolated islands surrounded by cities, or
adjacent to the urban growth boundary. Because these areas are scattered across the county, the
efficient provision of services is difficult. The lack of a substantive tax base exacerbates these difficulties,
and the cost of serving these areas reduces the amount of money available for regional services, and for
local services in rural areas. Therefore, King County has a strong fiscal interest in seeing the remaining
urban unincorporated areas annexed within the next several years.
The annexation of urban unincorporated areas is also good public policy. The State Growth Management
Act and the regionally adopted Countywide Planning Policies stipulate that counties are the appropriate
providers of regional services, and of local services to the rural area. For their part, cities are the
appropriate providers of local urban services to all areas within the designated urban growth boundary.
This logical split of government services is in part a reflection of the greater taxing authority afforded to
cities by the State Legislature. County taxing authority remains similar to what was historically adopted in
the state constitution. Annexation is a means to achieve the desired governmental service and land use
vision set forth in regional policy and state law.
Although it is the policy of the county to promote annexation, its ability to do so is extremely limited. State
laws provide the cities, county residents and property owners with the authority to initiate the annexation
process. A successful annexation initiative depends on establishing a collaborative and ongoing dialogue
between the three affected interest groups: residents, the county, and the affected city. King County has
a long history of engaging in annexation discussions with urban unincorporated area residents, and will
continue to do so. The county will also continue to work collaboratively with the cities to plan for orderly
and timely governance transitions.
The policies in this section are intended to guide the county's decision making on annexation-related
issues to ensure the needs of citizens in the urban unincorporated area are considered, and that a
smooth transition from county to city government occurs.
U-201 In order to meet the Growth Management Act and the regionally adopted Countywide
Planning Policies goal of becoming a regional service provider for all county residents and
a local service provider in rural areas, King County shall encourage annexation of the
remaining urban unincorporated area. The county may also act as a contract service
provider where mutually beneficial.
U-202 To help create an environment that is supportive of annexations, King County shall work
with cities and with Unincorporated Area Councils, neighborhood groups, local business
organizations, public service providers and other stakeholders on annexation-related
activities. King County will also seek changes at the state level that would facilitate
annexation of urban unincorporated areas.
U-203 The Interim Potential Annexation Areas Map adopted by the Growth Management Planning
Council illustrates city-designated potential annexation areas (PAAs), contested areas
(where more than one city claims a PAA), and those few areas that are unclaimed by any
city. For contested areas, the county should attempt to help resolve the matter, or to enter
into an interlocal agreement with each city for the purpose of bringing the question of
annexation before voters. For unclaimed areas, King County should work with adjacent
2-23 September 2004
cities and service providers to develop a mutually agreeable strategy and time frame for
annexation.
U-204 King County shall support annexation proposals that are consistent with the Countywide
Planning Policies and the Washington State Growth Management Act, and when the area
proposed for annexation is wholly within the annexing city's officially adopted PAA, and is
not part of a contested area.
U-205 King County shall not support annexation proposals that would:
a. Result in illogical service areas;
b. Create unincorporated islands unless the annexation is preceded by an interlocal
agreement in which the city agrees to pursue annexation of the remaining island area
in a timely manner;
c. Focus solely on areas that would provide a distinct economic gain for the annexing
city at the exclusion of other proximate areas that should logically be included;
d. Move designated Agricultural and/or Forest Production District lands into the Urban
Growth Area; or
e. Apply zoning to maintain or create permanent, low-density residential areas, unless
such areas are part of an urban separator or are environmentally constrained,
rendering higher densities inappropriate.
U-206 King County shall favor annexation over incorporation as the preferred method of
governance transition. King County will not support incorporations when the proposed
incorporation area is financially infeasible.
U-207 King County shall work with cities to jointly develop preannexation agreements to address
the transition of service provision from the county to the annexing cities. The
development of such agreements should include a comprehensive public involvement
process. Pre-annexation agreements may address a range of considerations, including
but not limited to:
a. Establishing a financing partnership between the county, city and other service
providers to address needed infrastructure;
b. Providing reciprocal notification of development proposals in PAAs, and opportunities
to identify and/or provide mitigation associated with such development;
c. Supporting the city's desire, to the extent possible, to be the designated sewer or
water service provider within the PAA, where this can be done without harm to the
integrity of existing systems and without significantly increasing rates;
d. Assessing the feasibility and/or desirability of reverse contracting in order for the city
to provide local services on the county's behalf prior to annexation, as well as the
feasibility and/or desirability of the county continuing to provide some local services
on a contract basis after annexation;
e. Exploring the feasibility of modifying development, concurrency and infrastructure
design standards prior to annexation, when a specific and aggressive annexation
timeline is being pursued;
f. Assessing which county-owned properties and facilities should be transferred to city
control, and the conditions under which such transfers should take place;
g. Transitioning county employees to city employment where appropriate;
h. Ensuring that land use plans for the annexation area are consistent with the
Countywide Planning Policies with respect to planning for urban densities and
efficient land use patterns; provision of urban services, affordable housing, and
transportation; the protection of critical areas; and the long-term protection of urban
separators;
i. Continuing equivalent protection of cultural resources, and county landmarks and
historic resources listed on the King County Historic Resource Inventory;
j. Maintaining existing equestrian facilities and establishing equestrian linkages; and
k. Establishing a timeline for service transitions and for the annexation.
September 2004 2-24
As part of its annexation initiative, King County will explore new options for revenue generation to make
the provision of services to urban unincorporated areas financially sustainable. If annexation is not
occurring at a pace consistent with the intent of these policies, the county may consider utilizing its land
use authority to encourage new development that will generate higher tax revenues.
U-208 King County shall consider initiating new subarea planning processes for the urban
unincorporated areas to assess the feasibility of allowing additional commercial, industrial
and high-density residential development through the application of new zoning.
2-25 September 2004
111 .. Ec1n1mic Deve1oumen1
A. Overview
King County's economy is the largest and most significant economy in the Puget Sound Region (King,
Kitsap, Pierce, and Snohomish Counties) and in Washington State. In 1998, King County had:
• 1,127,000 nonagricultural jobs, or 42.4% of the state's 2,655,000 jobs and 67.9% of the region's
1,660,000 nonagricultural jobs.
• A $52.9 billion payroll, or 52.3% of the state's $101 billion payroll and 74.5% of the region's $70.9
billion payroll.
• Almost 83,900 business firms (excluding sole proprietorships), which is 36.7% of the state's 228,500
firms and 66% of the region's 127,200 firms.
• A population of 1,774,300 or 29.4% of Washington State's 6,041,700 population and 52.8% of the
region's 3,362,000 population.
The foundation for a vibrant and sustainable economy consists of several factors including a favorable
business climate, a trained workforce, public infrastructure, land supply, predictable regulations,
advancing technology, affordable housing, and a healthy natural environment.
The policies in this chapter are designed to continue King County's long-term commitment to sustainable
economic development. They do so by promoting public programs and actions that support a strong
stable and diversified economy, one that is compatible with the environment and contributes to a strong
and stable tax base.
The policies also recognize businesses and the workforce as customers of an economic development
system; they support actions and programs that promote the strength and health of both groups.
General King County economic development policies include:
U-301 King County has a long-term commitment to sustainable economic development.
Sustainable economic development shall mean economic development that does not
exceed the ability of the natural or built environments to remain healthy while
sustaining growth over the long term.
U-302 King County policies, programs, and strategies shall recognize the importance of,
and place special emphasis on, retaining and expanding home grown firms in basic
industries which bring income into the county and increase the standard of living of
our residents.
U-303 King County policies, programs, and strategies will place special emphasis on
training low-income, low-skill residents for job opportunities with livable wages,
benefits, and wage-progression and retention strategies.
U-304 King County shall work to ensure that maximum economic benefit accrues to local
businesses and workers when public funding is included in the construction or
operation of large projects.
U-305 King County recognizes the environment as a key economic value in the region that
must be protected.
September 2004 2-26
•
King County's role in economic development is implemented at several levels as described in the
following policies:
U-306
U-307
U-308
At the multicounty level, King County should partner with other counties, regional
entities and the state, as appropriate, to devise and implement economic
development policies, programs and strategies for the benefit of the region.
At the countywide level, King County should partner with other jurisdictions,
economic development organizations, the Port of Seattle, and others, as appropriate,
to develop and implement policies, programs, and strategies that set the general
framework for economic development within the county for the benefit of the county
as a whole.
Within the unincorporated area, King County should partner with local businesses,
unincorporated area councils, and others, as appropriate, to develop and implement
policies, programs, and strategies that promote appropriate local economic ·
development .
At all three levels, King County seeks to coordinate and partner with private and public organizations to
pursue mutually beneficial outcomes.
B. Business Development-Creation, Retention, Expansion, and Recruitment
King County's policies, plans, and programs should support a positive and healthy business climate that
enables local firms to stay globally competitive, quality-oriented, technologically advanced, and able to
pay good wages.
Industries and firms that export their products and services outside King County bring income into the
county and are considered basic, in economic terms. About 30% of the county's basic jobs come from
the export of manufactured goods; 42% come from the export of business services such as banking,
insurance, accounting, legal architectural, engineering, research and development, and computer
services; and 28% come from exports associated with wholesale trade, transportation, and public utilities.
Jobs in basic industry generally pay better than nonbasic jobs and support the nonbasic or secondary
part of the county's economy. In general, nearly one-half of the jobs in the county's economy are basic
and support the other half such as retail and personal services.
Local and national research over the last 20 years has concluded that homegrown, small businesses
create the majority of new jobs in a local economy. Additionally, roughly one of every four jobs in the
Puget Sound Region is dependent on international trade.
There is recognition, however, that the county's impact on the creation of new businesses is impacted by
the amount of available industrial and commercial land in unincorporated King County, which has
declined from approximately ten percent in 1994 to approximately 5.6 in 2000.
U-309
U-310
King County supports programs and strategies to help create, retain, and expand
homegrown businesses in basic industries, particularly within the county's
manufacturing and industrial areas.
King County supports programs and strategies, in partnership with the federal,
state, and local governments and the private sector, that provide technical
assistance to homegrown businesses including but not limited to:
a. Pollution prevention and assessments of contamination to enable
manufacturers to remediate contaminated property to continue or expand
production;
b. Technological, efficiency, and managerial assessments to enable manufacturers
to reduce costs and use smaller footprints for existing or expanded production;
2-27 September 2004
U-311
U-312
U-313
U-314
c. Mentoring, financial management training, and other technical assistance to
disadvantaged businesses, particularly in the construction industry, to help
them become competitive in the private sector;
d. Workforce recruitment, training and retention assistance.
King County supports programs and strategies for the targeted recruitment of firms
that will:
a. Support the county's basic industries by providing services that help keep
existing firms globally competitive, or
b. Export their goods or services and/or have the potential for high levels of growth
and wages.
King County supports programs and strategies to expand international trade
including those that:
a. Promote, market, and position the county for increased export, import, and
foreign investment opportunities;
b. Provide technical assistance, training, and opportunities for local firms wishing
to export.
King County supports programs and strategies to preserve and plan for an adequate
supply of industrial and commercial land including but not limited to:
a. In compliance with the State of Washington Buildable Lands legislation -RCW
36.70A.215 -and in cooperation with the cities, inventory and monitor the use of
industrial, commercial, and residential lands every 5 years. The first 5-year
report is due to the state in 2002;
b. In partnership with other jurisdictions and the private sector, advocate for a
regional Geographic Information System to track the supply of industrial and
commercial land;
c. Actively apply for federal, state, and other resources to help defray the costs of
assessment, remediation, and redevelopment of private and/or public
brownfields. Brownfields are defined as vacant or underdeveloped
industrial/commercial sites with real or perceived contamination;
d. Sell county-owned surplus industrial and commercial lands for development by
the private sector;
e. Promote the redevelopment and infill of industrial and commercial areas and
explore the feasibility of using incentives to achieve this goal;
f. Prevent the encroachment of nonindustrial uses on industrially-zoned land and
the rezoning of industrial land to other uses.
King County recognizes that adequate infrastructure is essential to support existing
economic activity and to attract new industry and development. The county
therefore supports programs and strategies to maintain existing infrastructure and
construct new facilities (transportation, utilities, schools, information,
communications), including an adequate supply of housing, necessary to
accommodate current and future economic demand.
The county recognizes the importance of traditional economic activities which may occur in conjunction
with or as a byproduct of other business activities in the rural area. Such examples could include
residents operating farms, ranches, logging operations or other small businesses and who use their
equipment to perform excavation services for others. While it is not the intent of the county to develop
these areas for commercial purposes, there is recognition that some proportion of landowners may
undertake complementary, small-scale commercial activities. The county values and supports these
types of economic activities in the rural area and does not wish to artificially limit them.
U-315 King County recognizes the importance of traditional economic activities that
support a rural lifestyle. While it is not the intent of the county to develop the
September 2004 2-28
•
unincorporated rural areas for commercial activities, county policy, regulations and
programs should support the preservation of traditional rural economic activities
and lifestyles.
C. Workforce Development -Skilled Workers, Employer Involvement and
Economic Opportunities
King County should address the ongoing workforce challenges of the Puget Sound region. The robust
economy of today and the last several years makes it very difficult for employers to find and retain both
skilled and entry-level workers. At the same time, many disadvantaged county residents have difficulties
gaining access to quality education, training, and support services needed to prepare them for the world
of work. Meeting these challenges successfully will depend on better strategies and working relationships
between business, government, labor, advocacy organizations, education and training institutions, and
human service providers.
Jobs that pay wages sufficient to support families are vital to the quality of life. However, training,
education. skill levels, and abilities vary from person to person. As such, it is important for King County to
support job opportunities for all residents with entry level jobs being essential to helping low-income, low-
skilled individuals enter the workforce, reduce their dependence on public resources, and move up and
out of poverty.
A family wage is a wage that allows a family to meet its basic needs without resorting to public assistance
and provides it some ability to deal with emergencies and plan ahead. This definition is taken from the
Northwest Job Gaps Study, produced by the Northwest Policy Center, although the study uses the term
livable wage instead of family wage. According to this study, the 1996 family (livable) wage for 11 urban
counties was $16.86 an hour or $35,079 a year for a single adult with two children.
For context, the 1998 King County average annual wage, excluding software workers, was $35,900.
Adding the average annual wage for software workers -$291,000 -increases the 1998 King County
average annual wage to $41,300. Adjusting the Northwest Job Gaps Study for inflation and costs specific
to King County, the 2000 family wage is $19.30 an hour or $38,740 for a single adult with two children.
As defined for this comprehensive plan, an acceptable entry-level wage pays a minimum of $8.00 per
hour (to be reviewed annually and adjusted as appropriate), provides benefits, and offers workers wage
progression opportunities. While an entry-level wage is a wage that provides workers greater economic
incentive than does being on welfare, it is not a family wage. Depending upon household size and
income, persons making entry-level wages in King County most likely require public subsidies in the form
of childcare, housing, food stamps and/or Medicaid. As skill levels and wages increase, workers become
less dependent upon public subsidies as they approach a family-wage level defined above.
U-316
U-317
King County supports assuming a leadership role in workforce development as a
member of the King County Workforce Development Council, established by the
federal Workforce Investment Act of 1998, composed of high-level representatives
from business, local government, labor, education and training institutions,
advocacy organizations and human service providers. The purpose of the council is
to coordinate and improve employment, training, literacy and vocational
rehabilitation programs to meet the needs of the workforce system's two customers
-employers and workers.
King County supports programs and strategies to provide employment and training
opportunities including:
a. Programs that facilitate employer involvement in hiring low-income and low-
skilled workers with limited experience and skills, and provide successful
strategies for skills training, job placement and retention for workers;
2-29 September 2004
b. Training for and placement of low-income and low-skilled workers in jobs in
growing industries that pay an entry-level wage of at least $8.00 per hour (in year
2000 dollars), provide benefits, and offer workers wage progression
opportunities. This hourly figure is to be evaluated during each update of this
plan and adjusted to reflect changes in cost-of-living or other similar indices and
consideration of market conditions;
c. School-to-work programs and effective alternatives for out-of-school youth; and
d. Services to enable unemployed, underemployed and dislocated workers to
obtain employment at a wage that enables them to be self-sufficient.
U-318 King County supports programs and strategies to address the barriers to entry-level
wage employment including:
a. Access lo transportation by providing transportation information and services to
jobseekers and workers;
b. Access to childcare by increasing the availability and affordability of quality
childcare for low-income families.
U-319 King County supports apprenticeship opportunities for disadvantaged populations
on county public works projects in order to address the forecasted shortage of
construction trades workers and to encourage family-wage job opportunities.
U-320 King County supports workforce development programs that are integrated with the
county's economic development strategies, such as training and employment as
environmental clean-up technicians for low-income residents of brownfields
communities.
D. Regional Plans, Regional Projects and Public-Private Partnerships
King County will consider participation in (1) regional economic development plans and projects that
provide benefits to multiple jurisdictions or (2) require a partnership between the public and the private
sector to be feasible. For either regional plans and projects or public-private partnerships, the county will
base its investment decision upon a full and thorough analysis of the public costs and public benefits of
proposed projects.
U-321 King County shall partner, where feasible, with jurisdictions and other stakeholders
to develop subarea economic development strategies to promote development and
redevelopment in areas that can accommodate growth.
U-322 King County shall cooperate in efforts to establish and maintain county and regional
economic development strategies to provide for orderly, sustainable, and equitable
economic growth throughout the Puget Sound Region.
U-323 King County should consider participation in the funding of regional economic
development projects when the project meets the following guidelines:
a. The project should support a firm in basic industry;
b. At least 75% of the jobs created by a firm, excluding management positions,
should pay a family wage;
c. The project is located within (1) an urban center or manufacturing industrial
center as designated in the Countywide Planning Policies, (2) other industrial
areas, or (3) business/office parks within activity areas which can be supported
by and promote transit, pedestrian and bicycle uses;
d. The firm or project will generate sufficient new tax revenue to repay the debt the
county incurs to support the project. The preferred average coverage ratio over
the life of county financing is two dollars of new revenue for every one dollar of
incurred debt;
September 2004 2-30
U-324
U-325
e. Other jurisdictions benefiting from a project must commit financial support
based on a mutually agreeable pro rata funding formula. The funding formula
will be established on a project-by-project basis;
f. The firm or project must create 1 new, permanent full-time, family-wage job for
each $35,000 of aggregate public investment; and
g. The firm or project should create all jobs within 3-5 years from project
completion.
King County shall foster the development and use of public/private partnerships to
implement economic development projects and programs. At a minimum, these
projects must demonstrate that they:
a. Cannot be accomplished solely by either sector;
b. Have an experienced and proven private partner(s);
c. Do not unduly enrich the private partner(s);
d. Provide tangible and measurable public benefits in terms of tax and other
revenue, construction and permanent jobs, livable-wages with benefits and a
wage-progression strategy, and public amenities; and
e. Will use the King County Jobs Initiative, or other entities with similar programs,
as their first source of referral for training and employing low-income, low-skill
residents in entry-level and semiskilled jobs.
Through local subarea planning and coordination with other agencies and
organizations, King County should use zoning, incentives or other measures to ensure
that an appropriate proportion of the land adjacent or near to major public
infrastructure facilities is used to capitalize on the economic benefit of that
infrastructure. The surrounding land uses should be buffered or compatible with
economic development uses.
2·31 September 2004
IV .. HDUS.iDU
A. Housing Choice and Opportunity Throughout King County
Adequate choices and opportunities are essential to fully address the spectrum of housing needs for all
King County residents. A basic goal of the Washington State Growth Management Act (GMA) is to
encourage affordable housing. Likewise, the King County Comprehensive Plan promotes affordable
housing for all county residents by supporting adequate funding, zoning, and regional cooperation to
create new and diverse housing choices in communities throughout the county.
Most housing is financed by and developed in the private sector. The ability of the private sector to
develop affordable housing is affected by a wide range of market forces. Local government actions such
as land-use policies, development regulations and infrastructure finance also have a significant impact on
housing affordability.
Public funding and incentive programs are essential to address housing needs of lower-income county
residents, including people with special needs, such as the elderly and people with disabilities. The
policies in this chapter address low-cost housing development, preservation and assistance programs
needed to ensure sale and adequate housing for lower-income and special needs residents.
In addition, the King County Consortium represents unincorporated areas and most county cities outside
of Seattle. This consortium prepares a Consolidated Housing and Community Development Plan which
outlines the needs, resources and housing goals to be achieved. An annual action plan details specific
housing and community development objectives.
1. Range of Housing Choices
lnterjurisdictional cooperation and public/private partnerships are needed to address the full range of
critical housing needs.
U-401
U-402
King County shall work with cities and the private sector to encourage a wide range
of housing within the Urban Growth Area to meet the needs of our diverse
population, support economic growth, ensure an equitable and rational distribution
of low:income and affordable housing throughout the county and provide housing
choices for people of all income levels.
Through subarea and regional planning with cities, incentives programs and funding
initiatives, King County shall plan for housing to meet the needs of all economic
segments of the population throughout the Urban Growth Area and within Rural
Towns. King County shall plan for construction or preservation of housing units
affordable to households as follows:
• 24% of housing stock should be affordable to households below 50% of the King
County median income;
• 17% of housing stock should be affordable to households between 50% and 80%
of the King County median income;
• 20% of housing stock should be affordable to households between 80% and
120% of the King County median income; and
• 39% of housing stock should be affordable to households above 120% of the
King County median income.
September 2004 2-32
-
Meeting these objectives will entail providing sufficient land for a variety of affordable housing such as
higher-density single-family homes, multifamily properties, manufactured housing, accessory apartments
and mixed-use developments.
U-403
U-404
U-405
U-406
U-407
U-408
U-409
U-410
U-411
King County, in partnership with other jurisdictions, shall evaluate achievement of
countywide and local goals for housing for all economic sectors of the population by
analyzing housing indicators, adopted land use regulations, actions that encourage
development and preservation of low and moderate-income housing and the effect
of market factors on housing development. The results of this evaluation shall be
used to develop new or revised policies, programs, regulations, and incentives to
better meet the Countywide Planning Policies' housing goals.
King County should work with cities to increase opportunities for affordable housing
development by assuring there is sufficient land capable of being developed for
multifamily housing, small lot single-family homes and townhouses, and
manufactured housing parks, and other types of housing, such as accessory
dwelling units, that tend to be affordable to low-, moderate-and middle-income
households.
King County shall provide opportunities for attached and detached accessory
dwelling units in urban residential areas and shall encourage all jurisdictions within
King County to adopt provisions to allow accessory dwelling units in their
communities.
King County should work with other jurisdictions to eliminate barriers for low-
income and special needs housing development.
King County should support housing development that is compatible with
surrounding uses by:
a. Providing information on potential development sites;
b. Funding services, amenities, infrastructure and access improvements;
c. Developing public financing techniques which give housing development and
redevelopment in designated areas, such as urban centers, a market advantage;
and
d. Making transit and rideshare services available.
King County should encourage land use and investment strategies to stimulate
mixed-use and mixed-income developments as a way to integrate neighborhoods
and increase housing choices.
King County should encourage affordable housing through redevelopment of
nonresidential buildings, such as schools and commercial buildings, in locations
suitable for housing and in ways that preserve significant historic features where
appropriate.
King County should encourage the development and preservation of residential
buildings that have shared facilities, such as single-room occupancy hotels and
boarding homes, to provide opportunities for lower rents.
King County shall provide opportunities and encourage other jurisdictions to
provide opportunities for housing types that provide lower-cost ownership
opportunities including manufactured housing, condominiums, townhouses and
cottage-style housing.
2-33 September 2004
U-412 King County should explore adding affordable housing as a benefit criteria in the
Transfer of Development Credits program, especially as the program is expanded to
include incorporated areas of King County.
U-413 All Urban Planned Developments (UPDs) and other large housing developments
shall provide a mix of housing types and densities, including housing that is
affordable to a range of households including low-, moderate-, and middle-income
households. This mix should include housing opportunities for households with
special needs, including the elderly and persons with disabilities.
2. Ensuring and Expanding Affordable Housing Resources
U-414 King County should initiate and actively participate in regional solutions to critical
affordable housing needs. Cities, community and housing representatives should
be invited to identify and implement solutions.
U-415 King County should work with cities and community representatives to establish
new, countywide funding sources for housing development, preservation and related
services, such that each city and King County contribute on an equitable basis.
U-416 King County should work with other jurisdictions, housing developers, and service
providers throughout the state to urge federal and state government to expand both
capital and operating funding for low-income housing, including low-income housing
for people with special needs.
U-417 King County should work with jurisdictions and housing providers across the state
to urge state and federal governments to expand funding for direct assistance
services such as rental assistance and emergency services.
U-418 King County should participate in developing and sustaining a coordinated, regional
response to homelessness that includes access to homelessness prevention
services, emergency shelter, transitional housing, permanent affordable housing,
and appropriate support services for homeless families, single adults, and youth.
B. Affordable Housing Development
The supply of affordable housing serving low-, moderate-and middle-income households has not kept up
with the increasing demand in the Puget Sound region due to the soaring costs associated with new
housing construction. In King County today, a substantial need exists for low-income rental housing and
for moderately priced homes that can be purchased by first-time homebuyers.
Existing units will provide some of the affordable housing needed for low-income households in the future.
However, with the projected growth in the number of low-to moderate-income households and the short
supply of lower-cost housing available today, new construction must include affordable housing. Efforts
to provide sufficient land and infrastructure and reduced development costs will help make new units
affordable. In addition, a combination of incentives programs and funding will help keep rents affordable
and expand opportunities for first-time homebuyers.
1. Development Incentives for Low-and Moderate-Income Housing
Incentives that will help developers provide low-and moderate-income housing include reduction in
development costs or an expansion of the development potential on the property.
U-419 Density bonuses and other incentives should be available to both single-family and
multifamily developments that provide rental or ownership housing affordable to
low-and moderate-income households and households with special needs.
September 2004 2-34
U-420 To reduce development costs for affordable housing projects, King County shall
exempt payment of impact fees for housing units that will serve low-income
households with incomes which do not exceed 80% of the median.
U-421 King County should explore methods to expedite plan reviews for housing projects
serving low-and moderate-income households, in coordination with other incentive
or subsidy programs.
U-422 King County shall explore coordination of incentive programs with cities to develop
common program guidelines and reduce administrative costs.
2. Housing Development Subsidies
Federal, state and local housing programs provide vital assistance to low-income households. King
County has used federal funds for housing for more than two decades, but it is not adequate for local
needs. During the past five years, King County also has used local funds for development and
preservation of affordable housing. As a result, residents have more housing choices. Residents who
need emergency housing can stay in the community of their choice and their children can continue to
attend schools. Local housing funds have also leveraged significant private investment as well as other
public funding resources.
Housing for very low-income households is usually developed by private, nonprofit agencies or by public
housing authorities. By using federal subsidy programs administered at the state or local level, private
for-profit developers and lenders also are active in low-income housing development.
U-423
U-424
U-425
U-426
U-427
U-428
King County shall give priority in its housing funding programs to developments that
serve low-income individuals and households, secure appropriate housing options
for people with special needs, prevent displacement of low-income people, or
provide low-income and special needs housing along with social services.
King County should explore increasing affordable housing opportunities, especially
in areas with an existing or forecast shortage of affordable housing, through new
programs, development incentives, and changes to funding program guidelines to
facilitate new construction, rehabilitation, and acquisition to preserve affordable
housing.
King County should seek opportunities to fund programs and projects where county
funds are matched by additional public and private loans and contributions,
increasing the amount of housing that can be developed.
King County should expand its use of surplus county-owned property and air-rights
over county-owned property for affordable housing and should explore its use for
other public benefits, such as human services, and consider conveyance of
properties to public or nonprofit housing developers and agencies at below-market
cost. In communities where the home ownership rate is lower than the county
average, surplus county property shall be targeted for housing development that
would expand the stock of owner-occupied, low-or moderate-income housing.
King County should support the efforts of nonprofit developers and housing
agencies to increase the supply of housing for low-income households, through
technical assistance and funding for capacity building, training, and predevelopment
activities.
King County should encourage and support efforts by nonprofit housing developers,
housing agencies, and service providers to develop long-term nongovernment
2-35 September 2004
funding sources such as planned giving, endowments, and related economic
development ventures.
U-429 King County should support programs that provide apprenticeship and employment
training in the building trades through affordable housing development. King
County should explore ways to partner with nonprofit housing developers in offering
pre-apprenticeship, apprenticeship and employment training opportunities.
C. Preservation of Existing Affordable Housing
This plan calls for more residential growth by preserving existing housing stock and developing new units
on vacant parcels within established neighborhoods. These locations can offer affordable housing that is
close to jobs, transportation and services. Housing development can also provide welcome
improvements to communities suffering from a lack of investment. However, new development in
established communities may result in the loss of existing low-cost housing. For example, when existing
affordable housing stock is demolished or upgraded to create market rate units, neighborhoods lose
housing for its low-income residents. Low-cost housing is a community resource we should strive to
preserve.
Redevelopment policies must be balanced with the need to preserve existing low-cost housing and
neighborhoods. Retention of affordable housing can be encouraged through appropriate zoning and
development regulations, financial incentives, rehabilitation programs, historic preservation, and
acquisition strategies.
Additionally, preservation of affordable housing minimizes health and safety risks and provides residential
stability. Historic features to existing buildings are also preserved. In combination, these efforts increase
livability and help establish the character of existing neighborhoods.
U-430 King County should develop and expand incentives and subsidy programs to
preserve affordable housing threatened by market forces and expiring federal
subsidies. Relocation assistance and replacement housing should be developed,
where feasible, to help low-income households when displacement is unavoidable.
U-431 King County should explore land use and financial incentives to preserve and
improve existing housing in redeveloping areas through the use of programs such
as transfer of development rights, tax credits and tax abatements for low-income
housing and tax abatements and restoration loans for housing designated as an
historic landmark.
U-432 King County should assist owners of rental properties serving low-and moderate-
income residents to acquire financing for building health and safety improvements
in exchange for long-term agreements to maintain affordable rents.
U-433 King County should work with financial institutions and other housing agencies to
expand resources for housing rehabilitation through techniques such as reverse
mortgage programs and loan pools.
U-434 King County should coordinate preservation of existing affordable housing with city
and county historic preservation programs and incentives, and should promote
preservation and restoration of significant historic features in the rehabilitation of
existing buildings and sites for housing.
U-435 King County should support ongoing efforts to maintain and preserve existing
mobile home parks, at an appropriate level of safety and habitability, as a source of
affordable housing for low-income homeowners through zoning, funding for
acquisition and rehabilitation of parks and homes.
September 2004 2-36
U-436 King County should consider the constraints of rehabilitation, legalization of
accessory dwelling units, and historic preservation, so usable structures are
rehabilitated to an appropriate level of safety and habitability.
U-437 Development standards should promote lower-cost infill development such as
accessory dwelling units and cottage-style housing in a manner that allows existing
housing to be retained through measures such as an innovative or flexible building
envelope, access and infrastructure standards.
D. Access to Housing
An important goal of addressing affordable housing needs is the successful integration of housing for low-
income households into the larger community. This can be accomplished by:
• Siting community facilities and affordable housing with convenient access to employment,
transportation and services;
• Adopting favorable land use policies and regulations;
• Increasing housing choices for special needs residents;
• Making reasonable accommodations for people living with disabilities;
• Permitting group living situations with supportive services; and
• Establishing positive relationships with neighbors of affordable housing.
Publicly funded developments can contribute to increasing access to housing for lower:income and
special needs residents through new construction or acquisition and rehabilitation of existing housing.
For special needs groups, public policies favor community-based, independent living in small residences
such as single-family homes or apartments. These policies are supported by the King County Fair
Housing Ordinance as well as state and federal laws that prohibit housing discrimination against
protected classes, including people with disabilities.
U-438
U-439
U-440
King County shall promote opportunities for publicly funded housing, including
housing for low-income people with special needs, by:
a. Adopting land use policies and regulations that treat publicly funded housing
and other low-income housing the same as housing of a similar size and density;
b. Adopting funding and program policies that encourage integration of assisted
housing within communities and a fair distribution of publicly funded housing
throughout the county. However, mandatory dispersion requirements which
limit where publicly funded housing may locate, should not be applied; and
c. Encouraging developers and owners of publicly funded housing units to
undertake activities to establish and maintain positive relationships with
neighbors.
King County shall make reasonable accommodations in its rules, policies, practices
and services when such accommodations may be necessary to afford persons with
disabilities equal opportunity to use or enjoy a dwelling.
King County should explore standards for publicly funded housing that:
a. Increase the ability of people with special needs to visit or have physical access
to housing units regardless of their residency status;
b. Allow household members to age in place; and
c. Include universal design principles that increase the amount of housing that is
accessible and usable by all persons.
2-37 September 2004
U-441 King County should support the ability of people, especially the elderly and persons
with disabilities, to find housing opportunities that allow them to live as
independently as possible in the housing and community of their choice.
U-442 King County shall prohibit special requirements through land-use regulations,
restrictive covenants and conditional or special use permits that limit the ability of
persons from protected classes (as defined in the King County Fair Housing
Ordinance) to live in residences of their choice.
U-443 King County shall permit group living situations, including those where residents
receive such supportive services as counseling, foster care or medical supervision,
within a single-family house or apartment.
U-444 King County should work with housing industry representatives to identify and
remove barriers (such as real estate marketing, finance or insurance practices) that
restrict housing choices and opportunities for low-and moderate-income people and
people with special needs. ·
U-445 King County should use land use planning and funding programs to help site
community facilities and assisted publicly funded housing so that low-and
moderate-income residents and persons with special needs have convenient access
to community and transportation services.
E. Reducing Development Costs
Rising costs have contributed to increases in rents and housing prices at all price levels. These costs are
associated with land acquisition, construction, financing, permit processes, roads and utilities and market
demand. Although some of these cost increases fall outside the control of local governments, others are
directly affected by public policy decisions. Public policies should be evaluated for implications related to
the cost of housing development. Cost-saving approaches should be studied. Strategies for increasing
favorable zoning, regulations and infrastructure can significantly cut housing development costs. These
will help curtail rising housing costs and increase the amount of new, affordable housing units.
U-446 King County should pursue land use policies and regulations that result in lower
development costs without loss of adequate public review, environmental quality or
public safety and do not reduce design quality, inhibit infrastructure financing
strategies, or increase maintenance costs for public facilities.
U-447 King County shall continue to improve development standards to allow higher
densities and flexibility of housing types in all residential zones, in order to best
accommodate the environmental conditions on the site and the surrounding
neighborhood when planning housing developments.
U-448 King County should encourage the use of area-wide Environmental Impact
Statements when plans are developed for activity centers, areas identified for
redevelopment or other neighborhoods to provide a more complete analysis of
cumulative environmental impacts and reduce the time and cost of environmental
review for individual developments.
U-449 King County shall seek to minimize the time necessary to process development
permits to meet affordable housing and environmental goals and community and
aesthetic concerns.
U-450 King County should encourage the formation of common development codes and
standards with cities, sewer and water districts and other permitting agencies to
increase predictability and reduce development costs.
September 2004 2-38
U-451 King County should develop new partnerships with public and private lending
institutions to find solutions that reduce housing financing costs for both builders
and consumers.
F. New Housing Models
The characteristics of people seeking housing continue to change. Today, there are more single adults
living alone or in shared housing than ever before. More families are single-parent households. Many
households have two parents working full-time. As the population ages, more seniors will need housing.
King County can assist in the development of housing types that meet the needs of these individuals and
families by funding affordable housing, revising development standards and/or expediting permit
processing. Demonstration projects can provide needed housing for low-income households and test
new models for housing simultaneously.
U-452 King County should assist in development of innovative, affordable demonstration
projects by exploring alternative land development, flexible development standards,
and construction techniques.
U-453 King County should encourage new housing models by supporting projects such as
owner-built housing, land trusts for rental and ownership housing, and other
innovative developments.
U-454 King County should support transit-oriented development that expands housing
opportunities at locations near frequent transit by engaging private and nonprofit
entities in an investment/development partnership. Public transit funds should be
used only when it is shown that the public transit benefit of such investment is equal
to or greater than the cost. King County should support efforts to incorporate
affordable housing in transit-oriented development.
U-455 King County should explore the feasibility of allowing five-story wood frame
construction as a technique that will increase the availability of multifamily housing
while lowering development costs and maintaining fire safety.
U-456 King County should support cottage-style housing development that clusters a
limited number of small scale detached units around a common green space at a
density level that is up to twice that allowed by base density. The general character
and size of cottage-style development should be controlled in the same manner that
creates compatibility with a single-family neighborhood.
U-457 King County should encourage development of residential communities that achieve
lower prices and rents through shared common houses, open spaces and
community facilities.
G. Direct Assistance to Households
In many cases, the most effective form of housing assistance is direct assistance to low-or moderate-
income households. This approach is commonly used for first-time homebuyer programs, which provide
reduced-rate mortgages or assistance with closing costs. These forms of assistance increase options for
homebuyers and enable them to find housing they prefer. Federal programs also provide direct rental
assistance to low-income households to help pay rent in public and privately owned rental housing.
In many cases, the most-effective form of housing assistance is direct assistance to low or moderate-
income households. This approach is commonly used for first-time homebuyer programs, which provide
2-39 September 2004
reduced-rate mortgages or assistance with closing costs. These forms of assistance increase options for
homebuyers and enable them to find housing they prefer. Federal programs also provide direct rental
assistance to low-income households to help pay rent in public and privately owned rental housing.
1. Homeowner Assistance
U-458 King County should work with local lenders to expand assistance for first-time
homebuyers, including homebuyer education and counseling, low-cost financing
and assistance with down payments and closing costs.
U-459 King County should provide financial assistance for housing rehabilitation to low-
income home owners, including owners of mobile homes residing in parks, and
through community-based repair programs, such as tool banks or painting
programs.
2. Renter Assistance and Homeless Prevention
U-460 King County should support programs that help prevent homelessness, such as
emergency rental assistance, mortgage default counseling, and improvements to
emergency services referral networks.
U-461 King County should support programs that assist low-income renters to remain in or
to gain access to private market housing, such as revolving loan funds that cover
utility and damage deposits, and rental assistance programs.
U-462 King County should support programs that provide landlord-tenant counseling,
workshops and mediation in landlord-tenant disputes, as well as legislation which
protects the rights of tenants and landlords, such as fair rental contracts.
H. Balancing Jobs and Housing
As the population of the Puget Sound region grows, King County is expected to remain the major
employment center of the region. As job growth occurs, the workers for these jobs must be
accommodated with adequate opportunities for housing. If a balance of job growth and housing
availability is not achieved, these workers will need to live longer distances away from their jobs, thus
increasing pressures upon transportation systems.
U-463 King County shall work with the Growth Management Planning Council or its
successor and the private sector to support development of an adequate supply of
housing commensurate with job growth within the county and its cities. To attain
this goal, King County shall:
a. Support job and household growth targets and policies established in the
Countywide Planning Policies;
b. Establish performance measures to gauge how jurisdictions are accommodating
growth;
c. Participate in buildable lands inventories, market analyses and other studies to
evaluate if sufficient land capacity is available for residential development; and
d. Work with cities to ensure additional actions are taken throughout the county to
accommodate and promote residential development when job growth causes
great demand for housing and severe shortages in the availability of housing for
new workers in the county.
September 2004 2-40
•
•
v. Human Services
People are King County's most valuable resource. Their well being affects the prosperity of the region.
King County's vision for the future includes livable, safe communities that are attractive to families,
thriving cities, healthy rural communities and a robust economy. The availability of human services is an
essential component of this vision.
Regardless of age, cultural background, income or family size, everyone is likely to need human services
at some point. Human services range from youth recreation programs to mental illness programs to
social programs for senior citizens. Many needs associated with human services are circumstantial and
have nothing to do with income. Any one can have trouble locating quality childcare. Any one may need
help dealing with family violence or substance abuse problems. Naturally, people with low incomes have
the highest needs for human services, including help in meeting such basic needs as food, housing,
health care and job training.
King County helps address the human service needs of its residents in many ways, including financial
assistance for programs that serve residents who lack resources to meet basic needs. Although _there
are many funding sources, the amount is inadequate to meet rising human service needs. A large portion
of King County's resources for human services comes from the State of Washington. This money is
mandated to be spent on particular groups, such as people with developmental disabilities, people with
mental illness, people with substance abuse problems and veterans. The county also accesses its own
current expense fund to support other human services.
The policies in this section reflect the intent of the King County Framework Policies for Human Services
adopted by the King County Council in 1999.
A. King County's Role in Human Services
Over the years, King County has become a regional leader in providing human services. Activities
include:
• Resource Development and Administration: King County works aggressively to direct federal,
state, and private resources to our jurisdiction, and, where appropriate, administer available funds.
• Funder: King County uses a portion of current expense and criminal justice funds to support a
variety of health, human services and housing programs for people in need.
• Planner and Advocate: King County is proactive in anticipating and responding to the changing
needs of residents and communities.
• Partnerships: The county works with a variety of public and private partners to design, implement,
and evaluate better ways of providing human services and conducting associated business.
U-501 King County, in partnership with other jurisdictions, should help provide access to a
range of prevention, intervention and rehabilitative human services for all residents
of King County. Access to human services should be available in all areas of the
county. In order to achieve the goal of equitable countywide distribution, residential
human service facilities should be encouraged to locate in areas of King County
where factors such as high property costs currently discourage their location. In
communities where there is a disproportionate share of human service facilities and
providers located, King County should provide community amenities such as parks,
transit improvements, sidewalks, and community centers.
2-41 September 2004
U-502 King County should lead the development and implementation of quality,
countywide human service systems for its mandated service areas (mental health,
drug and alcohol, people with developmental disabilities, veterans, and public health
services). King County should execute this role chiefly through the mandates,
guidelines, and funding provided by the State of Washington and/or the federal
government.
U-503 King County, in partnership with other jurisdictions, should support nonmandated
regional human service systems for persons most in need.
U-504 King County should provide local services such as family, youth, and senior social
and recreation programs; local food and clothing banks and community referral for
residents of the unincorporated area.
B. King County's Human Service Goals
The five community goals listed in U-505 were developed through a county-wide community process
sponsored by United Way of King County. All of the county's human services activities should support
one or more of these goals.
1. Community Goals
U-505 King County should promote healthy families and safe communities by supporting
activities that help attain the following community goals throughout King County:
a. Food to eat and a roof overhead. Ensure that the essential food and housing
needs of all people in King County are met.
b. Supportive relationships within families, neighborhoods, and communities.
Ensure all people in King County experience positive and supportive
relationships in their families and communities.
c. A safe haven from all forms of violence and abuse. Ensure that all people in
King County are safe and feel secure in schools, in their homes, and in their
communities.
d. Health care to be as physically and mentally fit as possible. Promote and
enhance the health of all people in King County, and assist them to attain and
maintain the greatest functional independence as possible.
e. Education and job skills to lead an independent life. Help all people in King
County become as economically self-sufficient as their abilities permit.
U-506 King County policies and regulations should help promote easy access to jobs,
housing, and services. In establishing and carrying out policies and regulations
regarding land use, transportation, economic development, facilities, and related
areas, King County should promote access to and availability of human services and
affordable housing for low-income residents and communities.
U-507 King County should ensure that its involvement in human services is sensitive to the
cultural, economic, and social diversity of King County. Toward that end, King
County should promote culturally competent and culturally relevant service delivery;
uphold federal, state, and local laws against discrimination; work to remove
obstacles that impair residents' ability to access human services and affordable
housing; and provide opportunities for diverse representation of people and
interests on King County's boards, commissions, advisory committees, and
planning processes.
U-508 King County should support efforts to break the cycle of poverty, promote personal
responsibility and reduce the overall need for human services. This includes
organizing and empowering residents and communities to be involved in the
September 2004 2·42
•
•
decision making that affects their lives. Services supported by King County should
do so in a manner that helps foster sell-determination and self-sufficiency to the
greatest extent possible.
2. Ensuring and Enhancing Human Services Resources
U-509 King County should work in the federal, state, and local government arenas, and
with the private sector, to garner additional human services and affordable housing
resources for King County residents to help further the community goals. This work
may include legislative advocacy, pursuit of grant funds, regulatory changes, and
related actions.
C. Assessing Use of Resources and Achievement of Goals
King County should ensure that human services funding and other activities are directed in an effective
and appropriate manner. The policies below and the King County Framework Policies for Human
Services outline an assessment and evaluation process to help ensure the county is responsive to
ongoing changes in achieving community goals. The assessment and evaluation process focuses on the
discretionary spending on human services and the necessary coordination with mandated human
services as appropriate.
U-510
U-511
U-512
U-513
U-514
King County should conduct an ongoing assessment and evaluation cycle to help
ensure its activities and use of resources for human services are responsive to
changing needs in the five community goal areas and other King County human
services priorities.
King County should periodically, but no fewer than every three years, produce a
King County Human Services Recommendation Report that describes strategies that
King County will pursue during the period covered by the Report.
King County should encourage and facilitate broad community participation -
including consumers and providers of services -in developing the King County
Human Services Report, and in the provision and evaluation of human services.
King County should actively coordinate with other local, regional, state, federal, and
private human services efforts in order to ensure that its human service activities,
including the use of resources, complement the programs and activities of others.
Wherever feasible, King County should participate in joint assessments with other
funders to analyze human service trends and needs.
Together with its community partners, King County should help to establish and
monitor key indicators of overall social and health conditions in King County. The
information shall be used to help determine progress towards meeting the five
community goals identified in U-505.
2-43 September 2004
VI. Suslainabl8 D8V810,PID8m
It is the goal of King County to work toward a model sustainable community where both the public and
private sectors seek to balance urban growth with natural resource protection. Sustainable development
seeks to achieve this goal by addressing the impacts of the built environment in which we live and work.
Sustainable development is implemented through planning, design and construction methods, including
green building and low-impact development (LID) that promote environmental quality, economic vitality
and social benefits.
Current development practices contribute significantly to the adverse impacts buildings have on our
environment. These impacts include heavy consumption of energy and water, large-scale production of
wastes, water pollution and contribution to greenhouse gas emissions. Implementing sustainable
development involves incorporating green building and LID practices into our policies through education,
incentives and regulation to help reduce these negative impacts.
Green building is defined as design, construction and operational practices that significantly reduce or
eliminate the negative impact of buildings through sustainable site planning, water savings, energy
efficiency, materials selection and enhanced indoor environmental quality for occupants. One strategy of
green building is LID. LID is an approach to land development that emphasizes maintaining or restoring a
site's natural hydrologic function by protecting and enhancing native vegetation and soils, minimizing
impervious surfaces and managing stormwater at its source.
A. Sustainable Development for King County Capital Improvement Projects
The King County Green Building Initiative establishes Executive policy to encourage and promote the use
of sustainable development practices in all buildings the county constructs, remodels and renovates. By
incorporating sustainable development practices when projects are in the planning and predesign phase,
economic benefits may realized, including the reduction of operating costs, enhanced asset value,
optimized building performance and a healthier workplace for its employees.
U-601 King County should incorporate sustainable development principles and practices
into the design, construction and operation of county facilities and county-funded
projects when economically feasible.
U-602 The use of green building practices should be accomplished within traditional
project budgets. If additional funds are sought for up-front costs, a life cycle cost
analysis of the project should be completed to determine the long-term benefits of
using green building practices.
U-604 King County should leverage its purchasing power related to capital improvement
projects to help expand ihe markets for green building products, including recycled-
content materials and clean, renewable energy technologies.
B. Sustainable Development in the Private Sector
King County seeks to foster innovative design and development techniques in the private sector that
reduce the negative impacts of site development and building construction while maintaining affordability
and economic development. Similarly, King County also encourages the use of low-impact site design
techniques to reduce impacts to aquatic resources.
September 2004 2-44
U-605 King County should encourage, support and promote the application of sustainable
development practices in all private sector development within the county. This may
be accomplished through working with residential and commercial developers to
incorporate habitat conditions, reduce impervious surface areas, protect ground and
surface water within a watershed, incorporate greater use of green building materials
and utilize systems that conserve resources, including those that use energy more
efficiently.
U-606 King County should identify and evaluate potential changes to land use development
regulations and building codes to support and promote green building and low
impact development. This may be accomplished through demonstration projects to
guide the application and refinement of regulations such as zoning, and road and
stormwater regulations.
C. Low-Impact Development
Current development practices can adversely impact water resources. Low-impact development (LID) is
a new approach to land development which works to match a site's natural hydro logic function by
protecting native vegetation and soils, reducing impervious surface and managing stormwater at the
source. LID techniques include retention of native vegetation, soil amendment, rainwater harvesting,
pervious pavement and bioretention.
U-607
U-608
U-609
King County should incorporate low-impact development principles and practices
into the design, construction and operation of all county facilities and county-funded
projects to the fullest extent feasible.
King County should work with residential and commercial developers to incorporate
low-impact development practices that protect native vegetation and soils, and
reduce impervious surface.
King County should identify and evaluate potential changes to land use development
regulations and building codes to support and promote low-impact development.
This may be accomplished through demonstration projects to guide application and
refinement of regulations such as zoning, subdivision, roads and stormwater
regulations.
2·45 September 2004
\\ . -··---·--r·--:-··--··---·-
! • I r.-·--• -",. \"? a • • ' i' ~· ; --~-1-··--;· -··--··
' •) LAKE 'f' . \ -,
) 'St'IOHEtJNE F~~Es r ·r,-.-~O~§tL_. / . I
.. ----\-.. --.. -.... --.. --. ·---. --.. --.. ---. --.. -
/ J ., ... · -,RK KENMORE' r~~;,~\W,8e.JD!NVIL .~E ._
\ ' ; -,. '., ~ '\ ~·
·-~ ,' '1': "l -I . , ; • / J j . . •
ii., I '.:'.-,_, , :.t"""'i~o<~e
., I -. , -... \ .. , ,,
i l • \ '/ / ,, "· \
~t -SE.ATCT'LE , '. ,' .~, ' ' .. ~J) 1
• ..t \K!RK (~:ND't / : 7 \\ ! ..... ,..."-Ii .·.1
-' i 9 ~ ; \
' . J ' • ! • . . ' ,, l . > ., · ., · f HUNT~ Y.AR,ROW'li ' . tf.T' PO 'N-· ' p "I ' \. ,,,_____ ' II .''. ' '~®IN·T.~
Y
. (' ' :.l. ~ 't, ,; ------ce:l' ',J?/" ·, ~ \.· ·. • . g ' ·;LYOC \.:
I :><) ,' I., • L \
I l .:::: 1 I-JILL ......
'· / \' ::: -··· ~ '· --:-,..: II t ~ I \ , , <2 rvtEQ ,N.I\,
'\, I • I ~ ~ \ ~,.. \
>;· i • \ ....
• ~
"'-.ri,. ' l .
l
'f
"\
"§ \
:::: ' ~ ~ " ~
(
1~,
(
\,-j.)
//'
fv/
).,,,
...... -( <~ ·~, ·\
., \ v~'/
,,,,"'
_)'--}
' <
-~ r," f
~J!@'(~
/ I
~'< .... -;,
p V ~s ~.
~-
)
I
, .~ '
~; v,.J ·,
' ! , '-...,
') I • ,r' ,'>, "f1 , . :-, c i ,-r ~ "' 1BEb_~EVaE
· ..... i , 1 ~---...., -, l · ~ , 'yy' • I ,r'"1 • , , I i ____ __. '·· \ • '
~ ~ " /SA fvHviAMIS H
~~ (,\
./
_,./
1a
, ,1 : I '"'t , -. B~A , a
'< \ ;
'
:. "I ! r . ... r,-c: .. u~ , ..
.. ,. , __j l ,::-. '-1 /'-~~-i --I ' • A-R1Sl-• "/ .~., • •· .... t \
...
I ;, J /. "' ,! . MERCER i. ~ SE.>ATTLE ' J ISLAND ,/ '\
't I • \ J ' • / t,
'\
' -~~~~:~:i~i,,{ -:_
E;astg~ff.4:c · ·-<.,4 \.··:6 oqgar .
"'
V)
,:,
,;:.
~
,;:,..
l
t' \ : . .
j ---11 I\ . \ • I\
' \ • \ • I // . ,,.1 '<:: •• / /. I.·
'II ;-·\.-\ \., \ ,• C,ty ot Soattle .EWG .ASJ.
(--.,--,---,}. ·-~, '\ Potent ,a l Annosation A rea .
1
I • ' \ •\ • \ ~ ' ~J i Nort~ Hi,\line \ .. \,.\ ~-.: --, \ ·.., . ~ .. .,.. L
~,•r , ' I' ~ :;t ·j~\ ,, 1
I ,,, .. YC..~ / \'
: BURIEN ----._, \ _.
\-: '/ TU KW! ~.A-----
\
r. • • I :, I : ...,
iSE.~T AC /
1 ? NORMA~DY . . ,, 1 N l;f PARK , ~ . /;, , /.' .
• i_ ,-_, ( '· ( \
~
~-
.....
l ,,
;;,
, DES .\ ,;
M0!:.,4ES ) '
••. i
/ KENT
. '~ .... ~
.. ,
1 • .,~
I 1::~ '
~
f ~·J . ! ; ' I . I '-.;I
L /,.~(~ · / ~{i e:·-Hm
, FEDERAL -f:E_st ' ! ( • •
•, ( ' r ,;.I / I ' g / . -~
", I ~'r I ... ·.AUBURN -~-/,
', /',: . ..,. / . . ~ ' .• --hr', .. /7-· ' ·' 1; '(,. ' -.. r ;-:;;., , .-,. I (,0 ', ,1/.,/.V,..~·'/· I • ' ' /_' // ; / ,,.., ' . -, ., / ",/ J ....: ... ,GONA . ·. //· I .r-, , . . ~
L M11 -rn {./, · PArlF'C.,.. I ~.·"..J 1 ---.. ---~-~-:.-_: .. _____ _
r 1
,4
~ •
~ .. -\
\
I
\ '
'\~) ,-
~l ~
• ,rl'
/1,
~
~
'
/
\ '
-~
Ii
·r-. --)
' ' ---~.._.-'~/ ___ /'_ -,_ --------'. -~ ·i
From Ordinance 12535 Section 1.0 :
Kino County and the City DI North Band will cor'rlinue .Joint plaMin<J
dlS<:uSS<ons regard ing sel'\flce del,very and financ,ng ,n th.i area .J,
affected by the ordinance. This area will likely not be app1opriate
for anne.ation by the C~y of North Send unti l the latter part (1he
years 2002 to 2012) of 1he 20 y~r plannin g horiion outiined in the
Countywjde Pla11ning Policies. /--1
/ .,.,,,.-·-c:::;:=. c:::;:=:i.;:::==;;;;_l!:;l;i::::::::::J = ; I •ill
,,----_/
_..,, \ I ~ r· --,'\. _,., .. _/., ,..., -
,'I\-~
rf;?'
fj
·~\
J
"o;'\ ;
'
,.
/J
I
I
J
'}
'\,.
Interim Potential
·Annexation Areas
Urban Areas which are within
()'
' 1, .....
'-\_ , ..... .. \
"· ......... ~ ..
\..-~ \,_,.•1 -• r·~-,
' , I
\_.,.. ·' .......... , -the designated PAA of two or more
cities--"OVERLA PS "--OR OTHER WISE
CONTESTED AREAS
\ _,f ···'\.
--, ' . ·' fi ··~ J '~--~·~ ,,.;..~ ..,.. ~
Urban Areas which are not with in
D t he designated PAA of any city-
0 GAPS"
D Green River Agricultural Districts -Pending Annexation
Potential Annexation Area
D Recognized by City-County
ln!erlocal Agreement
llB] lnterim Potential
Ann exation Areas
D Cities
D Pruks
N Urban Growth Area Bou ndary
Potential Annexation Areas Sources:
City Comprehensive Plans:
Algo na, August 1995
Bothell, December 1994
Federal Way , November 1995
Issaquah, Septe mber 1997
Ke nt. April 1995
Milton, Decembe r 1995
Comprehensive Plan Amendment
November 1997
Newcastle, June 1997
Pacific, July 1995
Redmond. December 1997
Renton , December 1997
SeaTac. December 1995
Seattle
Tukwila, December 1995
• ·· l-·-. ,I I ,D'-;;;,---· '
\. ...,,.~• '-".. N
"'-.__:
Countywlde Planning Policy Map ® .. +
Rural City Urban Growth Areas: 1ir King County ----
Carnation, Black Diamond, Duvall, Enumclaw, ~
North Bend (North Bend Potential Annexation Area
reflects resolution of a joint planning area, see
O rdi nance 12535 Section 1.0 ), Skykomish (not
shown), and Snoqualmie.
lnterlocal Agreement:
Auburn, March 1999
m.'lk><1Y'CJroioctil1<,oo\piAA\2004\2004...1pea.mxd
AWC \\Ode,; 707\(ji.-m~MP•\2004 t 2'1owc_?004 ,222_~.pdt
Tho wormatlon lndud.>d on llll& "'l>P hU bo<on CMIPilod b)'
IO\g CoUi'lly oliH lrom a '"'"OIJI ol sou._ t<nd I• Oub)od II> <,hMg•
without notioai. K~ Oeout,ty tneba "° ,ap,4Winl"l)ON or
WA~tiw.&. UJ)tlilU o, ilipUwd,. M to ia.:::cwacy , comp\al4ViM,S,.
timo~u:. °' ,ia,1s to trii Uiil:I m such WotmQUon. ~ Cuun1·1
aholl nol bo r..'olol 1o, any 0""""'\ oPAda\ lnditoct. tncldof>lol. 0<
oons,.Qr,(J1J'"°1i&I dQm Qg&S hdudr')Q. but not fmo:Q(J 10. trD.st
~IM 01 1o;t prolihi r~lt~ trom tn. Ult o, m\s·uu d th•
i"l.lorn\SdiM con?Wliid ffl this;; map. My Silo OI 1h11 m~ or
lnlorMatlon en this.-,.., Ii i,rohibllod -.°""' by "'"11.., """"'""""' a
IClr>gCOl,ldy.
~ 1 1 • -----• Mt'leo --~ ~~-
K ing County Compreh ensive Plan . 2004
Chapter Two, Urban Communities
October 2004
'\:·-·-
\
j
I
f
.I
(
I
I
i
i
i
\
i
I
f
\
\
J
I
i
\
~J 4/
(.,,. ~-.. ..,.,..
i ) -v I
I I
I
I
i
I
I
(
.>
I
I
)
,.., ....
Park
\ ~ -J
\ / ·,. -· /. . ;I ,·,\. '-. _,,.,. __x· ......... ____ ( :~
""·c{..">.,,
4>,i. --
King County Comprehensive Plan, 2004
Chapter Two, Urban Communities
m .\to ny,pfojects\complan\2004\2004_urban centers.m:xd
AWC \\o:tes707\gis -m\maps\2004 \2\2004_K CCF\awc_20041 222_urban_centers.pcf
-~==:·=--=~=·=====~=,~---------------1 '\ """""-"""' "°'!~------------. \\ ·-·-·--·-·---------------------·--------------------------------~;::·--------·,;.~ _____ s.,.,;;.r~,:!!:_ _____ r ~
-'~~~-~-----0J~
Urban Centers 2004
ti ____ !) _____ .. -·-·-·-------·-·-·,
~-j
! ~ .. _ .,
~ ~~-::;,~··. ,,,. .... :-.i
-'\ -·-·--..
I --· -----·· ·-·-·-·-·-·---
;-., --~
~.~
/_..f
•/
/
i
/
('./,.....,
r-·-·\ ·-·-·-·-·1
I '-. ,_,! j ~·-·i __ j ,., ____ f' ·-·-·-·-· '-",
/·--'
/
~; L t ...
J'aCiflC I ~-'i_J ._:
·~-Pi¥1i;.-e;:;::;.-,v I
I
,--! t ·--J
I ; _ _. .-
! ,·-......
t.,
I
<·( -w~,, ~--·'i , . .,..
• I '·, ,.. ___ .:. I • •·-·, j ______ ) i-·-
·-·-·
.i •.----,
i -.-r-'. ( L"'-f-)
·~'i.~·-·-:..1,_ i
'\ .... --·, .,..._)~, ...
• • ..... _. t,,q ('<t,
.:, "J.
,)~ ~
'·,. L-~
.,.,-" '"--
;" J "-\
( ~//~l ~ \.,-~ '-..~ r j ......__,.,,
I , . ....:.. -/
'\:::.• I
.) I ; '1,\ .... [.'. · .... ,_
I \ ~ ·,. . '
\ ' "-""L -.,. __ ,·,·----,,~-~ ,·-. ·, . . ' -..". ,. ____ ., · ....... ,.
~ ' ' _,,...,.-. ~ -., -'--~ ,J""'•-. • .... ~-·,
\-,I l....... '
\ ...... , J 'S:;/~"' '·~
·, ------------"' ~ ~-~---....... \. _;-· 1.--J ---'\.. \ .,. __
'-._J ....... ' \ ·" , .............. -...... ·,.,
.... ,.1 •/
>'
\
\ L~
\ #"'ii county ·-.......... . ~------' '-·---p~c11 Co,.;fity \.~ •,
_,..,--.i
T he inlormal ion included on this map has been compiled by
K ing County staff from a variety ol sources and is sl..bject to change
wtthoul notice. K ing County makes no represental ions or
warrant ies, exp ress or rnp!ied, as to accuracy, comple1onoss.
timelmes.s, Of righls to the use cJ such intonnation. K ing County
shall not bo Ii.ab le for any genera!, special indirect , incidental, or
consequential damages including, but not limited to, lost
rl:Nenues or klst profits rcsutting from !he use or misuse of !he
inform.a.lion contained on this map. ArPJ sale of this map °'
information on thi s map is p ro hibi1ed except by written pennissi,on o l
King County.
'\ \
.....,_ (.
The maps in the King County Comprehensive Plan and its technical appendic es are produc ed wi th a computer geographic ........... ___,.-..-.:=::-~
informari()(I system. They are reduced in size bur available at a larger scale. -......
r---~] Incorporated Areas
c_= __ ·_:] Tribal Lands
'"'-' Urban Growth Area Boundary
r"-.._., Municipal Watershed Boundary
• Unincorporated Activity Center
White Center
@ Community Business Centers
2 Benson Hill
3 Bo ulevard Park
4 Fairwood
5 Juanita-Woodinville Way/100th Ave. NE
6 Kingsgate
7 Klahanie
8 Lea Hill
9 North Lake Area
1 O Panther Lake
11 Ro x hill
12 Salmon Cre ek
13 Skyway
14 Top Hat
0 Neighborhood Business Centers
15 116th Ave. NE/NE 160th St.
16 Avondale Corner
17 Benson/SE 192nd St.
18 Beverly Park
19 Cascade
20 Jovita
21 Juanita Dri ve/N E 122nd Pl.
22 Juanita Driv e/N E 141 st St.
23 Juanita-Woo dinville Way/NE 145th St.
24 Lake Geneva
25 Martin Luther King Jr. Way/6oth Ave.-64th Ave. S
26 Mud Lake
27 Puget Sound Jr. High Site
28 Rainier Ave. S./S. 114th St.-S ." 117th St.
29 Spider Lake
30 Unincorporated South Park
Source: King County Department of Development and Environmenta l Services
Ci) King County
0 u 5 --------= ----~
1/J
-~~
N +
October 2004
Chapter Three
Rural Leg.acv and
Natural Resource Lands
Cha ter Three
Rural teuacv and Natural Resource lands
The landscape of King County's rural and resource areas is characterized by extensive forests,
small-scale farms, free-flowing rivers and streams that provide high-quality habitat for fish and
wildlife, and a wide variety of homes found in rural cities, small historic towns, and scattered on
lots in a broad range of sizes. Large-scale, commercial forestry and mining have been the
traditional land uses in the eastern half of King County where soils are thin and rocky, while
farming continues in the prime soils found in the river valleys. Many rural residential communities
are focused on scenic resources such as lakes, rivers and territorial views, or to lifestyle activities
such as the keeping of horses.
The glacial soils and terrain in the rural and resource areas also create significant environmentally
sensitive areas, such as steep, erodable slopes, wetlands and groundwater recharge areas.
Maintenance of tree cover, natural vegetation and wetlands are critical to prevention of erosion,
flooding, property and habitat damage, the continued functioning of the ecosystem and
preservation of rural character.
Conserving King County's rural and natural resource lands is integral to providing diversity in
lifestyle choices, continuing farming and forestry economies, protecting environmental quality and
wildlife habitat, and maintaining a link to King County's resource-based heritage.
Growth Management Act's Goals, Elements, and Requirements
Part I of this chapter satisfies the Growth Management Act's mandatory rural element by
designating rural lands in order to limit development in rural areas and prevent sprawl, by
permitting land uses that are compatible with the rural character established in the King County
Countywide Planning Policies, and by providing for a variety of rural densities; further, it satisfies
the mandatory land use element by indicating the population densities that are appropriate for the
Rural Area, and Goal 13 of the GMA by identifying and encouraging the preservation of lands,
sites, and structures that have historical or archaeological significance. It also maintains and
enhances natural resource-based industries and designated natural resource lands as required by
the act.
Part II of this chapter satisfies the Growth Management Act's Goal B to maintain and enhance
natural resource-based industries; Requirement 36.?0A.170 to designate natural resource lands;
Requirement 36.?0A.OBO optional conservation element by conserving natural resource lands.
King County's Rural Communities
King County's Rural Area, including communities such as the Hobart Plateau, Vashon Island,
Snoqualmie Valley and Enumclaw Plateau, contains predominantly low-density residential
development, farms, forests, watersheds crucial for both fisheries and flood control, mining areas,
small cities and towns, historic sites and buildings, archaeological sites and regionally important
recreation areas. These rural uses and activities occur adjacent to and interact with the county's rich
agriculture and forestry resources. The location of the Rural Area between the Urban Growth Area
and most Resource Lands helps to protect commercial agriculture and timber from incompatible
uses.
3-1 September 2004
Designation and conservation of a Rural Area maintains rural community character as a valued part
of King County's diversity. It also provides choices in living environments, maintains a link to King
County's heritage, allows small-scale farming and forestry to continue and helps protect
environmental quality and sensitive resources, such as groundwater recharge areas. Rural areas
also act to enhance urban areas and focus urban levels of development where they can be best
served.
King County is required to have a rural element in its comprehensive plan by the Washington
State Growth Management Act (GMA). A clear indication of which lands in King County will
remain rural also will foster better use of limited funds for facilities and services by allowing the
county to establish distinctly rural facility and service standards and to focus most public
resources on growth and services in the Urban Growth Area.
King County's Resource Lands
The growing, harvest, extraction, processing and use of products from Natural Resource Lands
play an important role in King County's economy by providing jobs and products for local use and
export. Natural Resource Lands also provide links to King County's cultural heritage, scenic views
and environmental benefits such as enhanced air and water quality. In large measure, King
County's quality of life is dependent upon the thoughtful planning and sound management of
these Natural Resource Lands to ensure their long-term conservation and productive use.
For many years, King County's Natural Resource Lands were poorly conserved and managed.
For example, only about one-third of the farmland existing in 1945 remains today. Lack of
understanding of natural resource value, inconsistent coordination between agencies, poor
operational practices, demand for more housing, lack of an adequate means to compensate
natural resource owners for the many nonmonetary values their lands provide and many other
reasons have diminished our available natural resource lands.
Efforts to maintain King County's Natural Resource Lands and the industries they support began
in earnest in the late 1970's. The land base and industries are further conserved by encouraging
development to occur as envisioned by the Washington State Growth Management Act (GMA),
which requires new development to be focused primarily in the Urban Growth Area. Under this
plan, Natural Resource Lands, including Designated Production Districts and sites of long-term
commercial significance, will have minimal new residential and commercial development. New
development that does occur will be designed to be compatible with active resource-based uses.
This section contains King County's strategy for conservation of these valuable Natural Resource
Lands and for encouraging their productive and sustainable management. The strategy consists
of policies to guide planning, incentives, education and regulation. Forest, farm and mineral lands
are not King County's only natural resources. Many other resource-based industries, such as the
fisheries industry, are influenced by King County's land use and planning policies. Policies for the
protection and enhancement of air, water, vegetation, fisheries, wildlife and other natural
resources can be found in this chapter and in Chapter 4, Environment.
September 2004 3·2
I. Rural Leuacv
A. Maintaining Rural Lifestyle
1. Rural Area Designation Criteria and Rural Character
The criteria set forth in this section were used to draw the boundaries of the Rural Area
designated by this plan.
R-101
R-102
It is a fundamental objective of the King County Comprehensive Plan to
maintain the character of its designated Rural Area. The GMA specifies the
rural element of comprehensive plans include measures that apply to rural
development and protect the rural character of the area (RCW 36.70A.070(5)).
The GMA defines rural character (RCW 36.?0A.030(14)). Rural development
can consist of a variety of uses that are consistent with the preservation of
rural character and the requirements of the rural element. Rural development
does not refer to agriculture or forestry activities that may be conducted in
rural areas (RCW 36.?0A.030(15)). In order to implement GMA, it is necessary
to define the development patterns that are considered rural, historical or
traditional, and do not encourage urban growth or create pressure for urban
facilities and service. Therefore, King County's land use regulations and
development standards shall protect and enhance the following components
of the Rural Area:
a. The natural environment, particularly as evidenced by the health of
wildlife and fisheries (especially salmon and trout), aquifers used for
potable water, surface water bodies including Puget Sound and natural
drainage systems and their riparian corridors;
b. Commercial and noncommercial farming, forestry, fisheries, mining and
cottage industries;
c. Historic resources, historical character and continuity including
archaeological and cultural sites important to tribes;
d. Community small-town atmosphere, safety, and locally owned small
businesses;
e. Economically and fiscally healthy rural cities and unincorporated towns
and neighborhoods with clearly defined identities compatible with
adjacent rural, agricultural, forestry and mining uses;
f. Regionally significant parks, trails and open space;
g. A variety of low-density housing choices compatible with adjacent
farming, forestry and mining and not needing urban facilities and
services; and
h. Traditional rural land uses of a size and scale that blend with historic
rural development.
The Rural Area designations shown on the King County Comprehensive Plan
Land Use Map include areas that are rural in character and meet one or more
of the following criteria:
a. Opportunities exist for significant commercial or noncommercial farming
and forestry (large-scale farms and forest lands are designated as Natural
Resource Lands);
3-3 September 2004
b. The area will help buffer nearby Natural Resource Lands from conflicting
urban uses;
c. The area is contiguous to other lands in the Rural Area, Natural Resource
Lands or large, predominantly environmentally sensitive areas;
d. There are major physical barriers to providing urban services at
reasonable cost, or such areas will help foster more logical boundaries
for urban public services and infrastructure;
e. The area is not needed for the foreseeable future that is well beyond the
20-year forecast period to provide capacity for population or employment
growth;
I. The area has outstanding scenic, historic, environmental, resource or
aesthetic values that can best be protected by a Rural Area designation;
or
g. Significant environmental constraints make the area generally unsuitable
for intensive urban development.
The Rural Area is comprised of all lands in King County outside of the designated Urban Growth
Area (UGA), and not including the designated Forest and Agricultural Production Districts. The
Rural Area is generally located east of the UGA, with the exception of the rural cities and their
UGAs, and also includes the entirety of Vashon-Maury Islands. Within the Rural Area, three land
use categories are applied: Rural, allowing low-density residential development, forestry, farming,
and a range of traditional rural uses; Rural Town, recognizing historical settlement patterns and
allowing commercial uses to serve rural residents; and Rural Neighborhood, allowing small-scale
convenience services for nearby rural residents.
While the GMA, the Countywide Planning Policies and King County's policies and regulations call
for protecting the Rural Area by limiting housing densities, there are many other features besides
density that characterize the Rural Area. Some of the most important features include:
integration of housing with traditional rural uses such as forestry, farming and keeping of livestock;
protection of streams, wetlands and wildlife habitat; preservation of open vistas, wooded areas
and scenic roadways; and reliance on minimal public services. King County is committed to
maintaining these features as well, and the policies in this chapter call for continuing and
expanding upon these efforts.
R-103 King County's Rural Area is considered to be permanent and shall not be
redesignated to an Urban Growth Area until reviewed pursuant to the Growth
Management Act (RCW 36.70A.130(3)) and Countywide Planning Policy FW-1.
2. Rural Resources
The Rural Area contains working farms and forests which contribute to healthy resource-based
industries. For example, Rural Area forestlands provide an important part of rural character, add
to the diversity and self-sufficiency of local economies and contribute to open space, wildlife
habitat and environmental quality. However, Rural Area land in farm and forest use has
significantly diminished since 1 985, mostly through the conversion of these lands to residential
uses. Pressures to convert from resource use include opportunities for significant profits based
on alternative uses, and the encroachment of residential and other development that conflicts with
the resource use.
Although most of King County's best farming and timberlands are within designated Resource
Production Districts, there is a significant land base for agriculture and forestry in the Rural Area.
King County has studied this land base and has identified rural forest areas where forestry will be
enhanced and protected. Special efforts to conserve the forest land base in particular are
necessary. Farming uses are adequately protected by rural zoning, but could be additionally
supported by incentive programs and possibly the Transfer of Development Rights program.
September 2004 3-4
R-104 Farming and forestry are vital to the preservation of rural areas and should be
encouraged throughout the Rural Area. King County should encourage the
retention of existing and establishment of new rural resource-based uses,
with appropriate site management that protects habitat resources. King
County's regulation of farming and forestry in the Rural Area should be
consistent with these guiding principles:
a. Homeowner covenants for new subdivisions and short subdivisions in
the Rural Area should not restrict farming and forestry;
b. Agricultural and silvicultural management practices should not be
construed as public nuisances when carried on in compliance with
applicable regulations, even though they may impact nearby residences;
and
c. County environmental standards for forestry and agriculture should
protect environmental quality, especially in relation to water and fisheries
resources, while encouraging forestry and farming.
R-105 Uses related to and appropriate for the Rural Area include those relating to
farming, forestry, mineral extraction, and fisheries such as the raising of
livestock, growing of crops, sale of agricultural products; small-scale cottage
industries; and recreational uses that rely on a rural location are also
appropriate.
3. The Rural Economy
An economic development strategy for the Rural Area can support and advance the unique
characteristics of rural King County. It is critically important for the Rural Area to sustain the farming
and forestry industries. The strategy needs to recognize the role of home businesses and industries
as well as a range of other businesses and economic clusters that can be compatible with rural
lifestyles and the rural character of the area. Rural economic development means maintaining and,
where possible, increasing the flow of income to rural households and revenues to rural businesses
and families.
R-106
R-107
King County recognizes and supports home occupations, home industries,
and other.small businesses that provide services to rural residents and are
part of traditional rural economic activities and lifestyles found in King
County's Rural Area. The county shall review its regulations and programs to
preserve this component of the County's Rural Area. The Executive shall
provide this analysis of the regulations and programs, along with any
recommended code changes, for review by the King County Council by
December 31, 2005.
King County shall develop and implement a rural economic development
strategy, which shall be consistent with the character and service levels of
the Rural Area. The strategy shall be developed in coordination with the
Rural Forest Commission, the Agricultural Commission, interested rural
citizens, and other stakeholders. This strategy shall be transmitted to the
King County Council by December 31, 2005, and shall include the following
components:
a. Identification of rural economic development policies, goals, objectives
and implementation tools necessary to bring income to the businesses
and residents of rural King County within the strictures of GMA;
b. Establishment of an action plan that will identify roles, expected
outcomes, milestones and schedules;
3.5 September 2004
c. Assessment of the strengths, weaknesses, challenges and opportunities
faced by the King County rural economy;
d. Inventory of the existing supply of commercial and industrial lands in the
Rural Area and an assessment of its sufficiency over the 20-year planning
horizon;
e, Identification of the types of businesses that should be encouraged and
supported in rural areas;
f. Identification of current obstacles to overall rural economic development
as well as impediments to the location or expansion of favored industries
that are consistent with rural character;
g. Identification of the implementation tools capable of supporting and
encouraging the retention, expansion and relocation of favored
businesses; and
h. Consistency with and in support of the APD and the FPD.
B. Forestry in the Rural Area
In 1995, King County worked with citizens and property owners to identify rural lands that were
currently being farmed, and rural lands that remained in a relatively forested state or were
appropriate for small-scale forestry uses. The lands were designated as Rural Farm Districts and
Rural Forest Districts, respectively. The King County Comprehensive Plan called for using
regulations and incentives to maintain land in the districts in large parcels, and to maintain and
encourage continued farming and forestry activities. The 1996 Farm and Forest Report
recommended a series of actions to protect the rural farm and forest land base as well as the
practices of farming and forestry, including the provision of technical assistance to aid property
owners in land management, outreach to owners of properties vulnerable to development,
creating opportunities for property owners to sell their development rights, and seeking funding for
public acquisition of rural resource lands. The report also recommended the continuance of the
King County Agricultural Commission, and the appointment of a Rural Forest Commission to
review the impact of proposed regulations on rural forestry and recommend incentive programs.
Since 1996, King County has been actively implementing the recommendations of the Rural Farm
and Forest Report through the Forestry Program. Throughout the Rural Area, King County
encourages small-scale forestry and land stewardship through a variety of land owner incentive
and community-based programs that:
a. Promote forest stewardship through education and technical assistance programs, such as
the Washington State Department of Natural Resources and the King County Cooperative
Extension Forest Stewardship Programs;
b. Provide technical assistance and information to landowner groups and community
associations seeking to implement land/water stewardship, habitat restoration and
management plans;
c. Create opportunities and incentives for voluntary, cooperative management of woodlots and
open space currently in separate ownership;
d. Offer technical assistance and information to landowners who are interested in managing their
forest for nontimber specialty forest products; and
e. Explore opportunities for providing relief from special levies and assessments.
R-108 The preservation of forest land and forestry throughout the Rural Area shall
remain a priority for King County. Landowner incentive programs, technical
assistance, permit assistance, regulatory actions and community-based
education shall be used throughout the Rural Area to sustain the forest land
base and forestry activities.
The Forestry Program will continue to evaluate additional ways to conserve rural resource lands
and encourage forestry. In addition, King County has identified properties for acquisition, and has
September 2004 3·6
worked in partnership with other jurisdictions and citizen groups to match high priority sites with
funding sources for permanent conservation. As of 2000, King County has purchased two
significant forest properties, the 1700-acre Taylor Mountain Forest and the 320-acre Ring Hill
Forest. The 313-acre Mitchell Hill Forest has been permanently preserved through the transfer of
development credits from Mitchell Hill to the City of Issaquah. An additional 725 acres of rural
forest land east of Ames Lake and at Sugarloaf Mountain have been permanently protected.
The Rural Forest Commission was appointed in 1998, and continues to work diligently to develop
new funding and incentive ideas for forest conservation. The commission recommended the
Rural Forest Districts be refined to provide a focus to those areas where the greatest
opportunities exist for retention of large, contiguous blocks of forest, and that these areas be
called "Rural Forest Focus Areas." The Rural Forest Focus Areas replace the Rural Forest
Districts.
While economic incentive programs and technical assistance are available to all property owners
in the Rural Area interested in pursuing small-scale forestry, special efforts to maintain forest
cover and the practice of sustainable forestry are warranted where there are opportunities to
sustain large, contiguous blocks of rural forest. The Agricultural and Forest Lands map identifies
such areas as Rural Forest Focus Areas, and notes the locations and boundaries of each focus
area.
R-109
R-110
Rural Forest Focus Areas are identified geographic areas where special
efforts are necessary and feasible to maintain forest cover and the practice of
sustainable forestry. King County shall target funding, when available, new
economic incentive programs, regulatory actions and additional technical
assistance to the identified Rural Forest Focus Areas. Strategies specific to
each Rural Forest Focus Area shall be developed, employing the combination
of incentive and technical assistance programs best suited to each focus
area.
The Rural Forest Focus Areas should be maintained in parcels of 20 acres or
more in order to retain large, contiguous blocks of rural forest. Regulations
or incentives should seek to achieve a maximum density of one home per 20
acres.
C. Farming in the Rural Area
The 1996 Farm and Forest Report provided a series of strategies tor conserving farmland and
sustaining farming within the designated Agricultural Production District where the prime
agricultural soils are found, and recognized that there are also areas outside the APD where
meaningful agricultural practices continue. The report identified areas where lands were in dairy
or crop production and enrolled in the current use taxation program, determined that the low-
density zoning in place in these areas was sufficient to protect the land base, and recommended
that landowner incentive programs be focussed there as well.
R-111 The county should develop specific incentives to encourage agricultural
activities in the remaining prime farmlands located outside the Agricultural
Production District. These incentives could include tax credits, expedited
permit review, reduced permit fees, permit exemptions for activities
complying with best management practices, assistance with agricultural
waste management or similar programs.
3-7 September 2004
D. Equestrian Communities
King County recognizes the contributions of equestrian livestock husbandry, training, competition
and recreation activities to the overall rural quality of life in King County. As growth occurs, open
land to sustain livestock and existing or potential trail segments may be lost to uncoordinated land
development and road improvements. Also, ESA requirements may limit livestock management
choices and the location of new equestrian facilities on land constrained by large riparian corridors.
The equestrian community designation in the Non-Motorized Transportation Plan is based on the
presence of some or all these factors in portions of King County's Rural Areas:
a. Proximity to a regional-level trail, designated by the State of Washington, King County or a
city, that is accessible to horses;
b. Tracts of land on which horseback riding is formally sanctioned or to which equestrian access
traditionally has been granted;
c. Concentrations of residential lots or acreage on which horses are kept;
d. Commercial or noncommercial stables, riding schools and arenas;
e. Supporting industries including but not limited to tack shops, feed stores or veterinarians; and
f. Riding or homeowner associations that promote equestrian activities.
While equestrian uses are permitted throughout the Rural Area, the Equestrian Communities Map
identifies those areas where continued equestrian uses are particularly supported and provides a
way for rural communities and the county to coordinate various actions to help equestrian activities
remain sustainable in King County.
R-112 King County should support the identified equestrian communities in the
Rural Area by providing facilities on King County rights-of-way where not in
conflict with the terms of utility easements to accommodate horse travel, by
maintaining equestrian links, including multiple-use trails, where appropriate,
and by adoption of supportive land use regulations for use of these areas for
horsekeeping. King County will work with local communities to identify and
protect multiple use trails and other public.trails in the identified Equestrian
Communities that support horse travel within the Rural Area.
R-113 Soft-surface multiple-use trails in corridors separate from road rights-of-way
are the preferred option for equestrian travel for safety reasons and to avoid
conflicts with residential activities associated with the street. Existing off-
road trails should be preserved during site development, with relocation as
appropriate to accommodate development while maintaining trail
connections. The King County Road Design Standards shall be revised, with
input from representatives of the equestrian community, to accommodate
safe equestrian travel within road rights-of-way. Where appropriate, capital
improvement programs for transportation and park facilities shall also enable
the use of new facilities by equestrians. Construction standards for multiple-
use nonmotorized trails to be established in road rights-of-way within
identified equestrian communities should assure a minimum eight-foot-wide
gravel shoulder, or provide a trail separated from the driving lanes by a ditch
or other barrier. Construction standards for soft-surface multiple-use
nonmotorized trails in corridors separate from road rights-of-way shall be
consistent with current trail construction and maintenance practices as
promulgated by the U.S. Forest Service.
R-114 King County's land use regulations should protect rural equestrian
community trails.by supporting preservation of equestrian trail links in
Equestrian Communities, protection of livestock from intrusions from
residential development, and encouraging subdivision layouts that preserve
September 2004 3-8
R-115
R-116
opportunities for keeping of horses. Representatives of the equestrian
community shall be given the opportunity to_review and monitor regulatory
and programmatic actions by King County, such as rural area development
regulations, that have the potential to affect equestrian uses.
Equestrian trails should be recognized as "linear parks" for purposes of the
county's Public Benefit Rating System.
County departments negotiating trades or sales of county land shall
determine whether any historically established trails exist on the property,
and assure that those trails are retained or replaced to assure that key
linkages to regional systems are not lost as a condition of the trade or sale.
3.9 September 2004
11. Boni Densities and Develoa•ent
A. Rural Growth Forecast
The GMA requires most new growth to be accommodated in Urban Growth Areas (UGA), yet growth
may be permitted outside the UGA provided it is not urban in character.
The Rural Area is not expected to accommodate large amounts of growth and allows for low-density
residential development and other traditional rural uses. The GMA requires that rural development
be contained and controlled to ensure the protection of rural character, assure the visual
compatibility of rural development with the surrounding rural area, protect environmentally sensitive
areas and habitat and protect against conflicts with natural resource uses such as farming, forestry
and mining.
In 2002, the Growth Management Planning Council adopted urban area targets to accommodate
the 2022 countywide population projections supplied by the state. These urban targets assumed
a rural area forecast of an additional 6,000 housing units during the period 2001 to 2022. No
attempt has been made to allocate this rural forecast to subareas of rural King County.
Since adoption of King County's initial comprehensive plan under GMA in 1994, annual building
permit activity in the Rural Area has continued to drop to an average of approximately 570 new
building permits per year for the period 1999-2002. Application of new zoning measures and
other regulatory tools have also helped to reduce subdivision activity, but if the current rate of 570
new homes per year continues, the Rural Area could be built out to its full capacity within 20 years
of the date of this plan.
The application of lower-density zoning or more restrictive standards could reduce the creation of
new lots, but there are limited opportunities to address development of existing legal lots. One
measure that would slow the growth rate on existing lots would be the establishment of an annual
limit on the number of building permits to be issued in the Rural Area. This alternative would be
more palatable if it were linked to a transfer of development rights program or a development
rights purchase program.
R-201
B.
A low growth rate is desirable for the Rural Area, including Rural Towns, to
comply with the State Growth Management Act, prevent sprawl and the
overburdening of rural services, reduce the need for capital expenditures for
rural roads, maintain rural character and protect the environment. King
County shall focus its resources on the unincorporated Urban Area until such
time that these areas become part of cities. All possible tools may be used to
limit growth in the Rural Area. Appropriate tools include land use
designations, development regulations, level-of-service standards and
incentives.
Residential Densities
The low-density residential living choices available in the Rural Area provide an important part of the
variety of housing options for King County residents. The residential land use policies in this section,
together with their implementing regulations, strike a balance between making rural housing
available to those who desire a rural way of life and keeping densities and the number of housing
units low enough so they can be supported by a rural level of public facilities and services, be
September 2004 3-10
compatible with nearby commercial and noncommercial farming and forestry and prevent or
significantly reduce adverse impacts of development on the natural environment. These policies and
implementing regulations could allow 14,000 to 24,000 more housing units at ultimate buildout in
addition to the roughly 58,000 residences existing in the designated Rural Area in 2000. The
Transfer of Development Rights Program will help reduce development capacity in the Rural Area,
and King County should continue to seek other programs that provide economic incentives for
property owners to voluntarily limit residential development of their land.
R-202 Residential development in the Rural Area should occur as follows:
a. In Rural Towns at a variety of densities and housing types, compatible
with maintenance of historic resources and community character; and
b. Outside Rural Towns at low densities compatible with traditional rural
character and uses, farming, forestry, mining and rural service levels.
The use of land and the density of development (measured as the number of homes or other
structures per acre or per square mile of land) are key determinants and contributors to the
character of the Rural Area, as described above in Section A. While human settlement of King
County's Rural Area has a wide variety of uses and densities, both the historical and desirable
range of uses and densities defined here are necessarily narrower and less intense than that
found in the Urban Area. Residential development at very low densities (including the land for
accessory uses, on-site sewage disposal and local water supply) consumes or will consume most
of the land in the Rural Area. Residential density may be the single, most important factor in.
protecting or destroying rural character that can be influenced by government policies and
regulations.
Low overall densities in the Rural Area will be achieved through very large minimum lot sizes or
limited clustering at the same average densities when facilities and services permit (for example, soil
conditions allow on-site sewage disposal on smaller lots). The Rural Area cannot be a significant
source of affordable housing for King County residents, but it will contain diverse housing
opportunities through a mix of large lots, clustering, existing smaller lots and higher densities in rural
cities and Rural Towns, as services permit.
Future development in the Rural Area will, to a great extent, be controlled by the availability of
transportation concurrency. Concurrency certificates are issued only to proposed developments
that meet strict level of service standards. In the Rural Area, this standard is an average
volume/capacity ratio of 0.69 during the afternoon peak period. Many of the traffic zones in the
Rural Area are near or already out of compliance; therefore proposed subdivisions are being
denied concurrency certificates. In the Transportation Chapter, policies prevent the construction
of road projects in the Rural Area for the purpose of increasing road capacity, meaning that these
zones will remain out of compliance.
R-203
R-204
The Rural Area should have low residential densities that can be sustained by
minimal infrastructure improvements such as septic systems and rural roads,
cause minimal environmental degradation and impacts to significant historic
resources, and that will not cumulatively create the future necessity or
expectation of urban levels of services. Concurrency certificates for proposed
new subdivisions in the Rural Area shall not be issued if trips generated by
such subdivisions would exceed rural transportation level-of-service
standards.
Rural area residential densities shall be applied in accordance with Policies
R-205 -R-209. Individual zone reclassifications are discouraged and should
not be allowed in the Rural Area. Property owners seeking individual zone
reclassifications should demonstrate compliance with R-205 through R-209.
3-11 September 2004
Although King County designated Resource Lands and zoned extensive portions of its territory as
Agricultural Production Districts or Forestry Production, very low residential densities adjacent to
Resource Lands are essential to minimize land use conflicts. In addition, a significant part of the
Rural Area land base is still used for farming or forestry uses. Therefore, suitability of lands for
continuing resource uses and proximity to designated Natural Resource Lands will be important
considerations in applying the lower rural densities.
R-205
R-206
R-207
R-208
A residential density of one home per 20 acres or 10 acres shall be achieved
through regulatory and incentive programs on lands in the Rural Area that are
managed for forestry or farming respectively, and are found to qualify for a
Rural Forest Focus Area designation in accordance with Policy R-109.
A residential density of one home per 1 O acres shall be applied in the Rural
Area where:
a. The lands are adjacent to or within one-quarter mile of designated
Agricultural Production Districts, the Forest Production District or legally
approved long-term mineral resource extraction sites; or
b. The lands contain significant environmentally constrained areas as
defined by county ordinance, policy or federal or state law, or regionally
significant resource areas or substantial critical habitat as determined by
legislatively approved basin plans or Watershed Resource Inventory Area
Plans; and
c. The predominant lot size is greater than or equal to 1 O acres in size.
For Vashon-Maury Island, a residential density of one home per 10 acres:
a. Shall be maintained on areas zoned RA-10 as of 1994 to help protect
community character and reduce adverse impacts on the island's
infrastructure; and
b. Shall be applied to areas with a predominant lot size of 10 acres or
greater and mapped as category I Critical Aquifer Recharge Areas.
A residential density of one home per 5 acres shall be applied in the Rural
Area where:
a. The land is physically suitable for development with minimal
environmentally sensitive features or critical habitat as determined by
legislatively adopted watershed based plans;
b. Development can be supported by rural services;
c. The land does not meet the criteria in this plan for lower density
designations; and
d. The predominant lot size is less than 1 O acres.
Although King County intends to retain low residential densities in the Rural Area, residential
development has occurred in the past on a wide variety of lot sizes. Both existing homes on small
lots and rural infill on vacant, small lots contribute to the variety of housing choices in the Rural Area.
In some cases, however, rural-level facilities and services (e.g. on-site sewage disposal, individual
water supply systems) may not permit development of the smallest vacant lots. The effect of Policy
R-209 is to recognize that some of the Rural Area has already been subdivided at a density greater
than one lot per five acres (for example, parts of the shoreline of Vashon Island), but not to allow
more than one home per five acres on unplatted acreage. Zoning to implement policies R-206
through R-209 has been applied through subarea and local plans and area zoning maps.
R-209 The RA-2.5 zone has generally been applied to rural areas with an existing
pattern of lots below five acres in size that were created prior to the adoption
of the 1994 Comprehensive Plan. These smaller lots may still be developed
individually or combined, provided that applicable standards for sewage
September 2004 3-12
disposal, environmental protection, water supply, roads and rural fire
protection can be met. A subdivision at a density of one home per 2.5 acres
shall only be permitted through the transfer of development credits from
property in the designated Rural Forest Focus Areas. The site receiving the
density must be approved as a Transfer of Development Rights receiving site
in accordance with the King County Code. Properties on Vashon-Maury
Islands shall not be eligible as receiving sites.
Accessory dwelling units provide opportunities for affordable housing, on-site housing for workers
and caretakers, housing for extended family members, and rental income for landowners.
However, detached accessory dwelling units function similarly to separate homes on separate
lots, and should be treated as such. When a subdivision is proposed for a property that already
has a house and a detached accessory dwelling unit, the house and accessory dwelling unit shall
count as two units. For example, on an RA-5 zoned 20 acre parcel, which could be subdivided
into four lots, the existing primary dwelling and the accessory unit in a separate building shall
count as two of the four units allowed on the site.
R-21 O Accessory dwelling units in structures detached from the primary dwelling
shall be counted as a separate dwelling unit for the purpose of lot
calculations under the zoning in place at the time of a proposed subdivision.
R-211 The King County Residential Density Incentive Program shall not be available
for development in the Rural zones.
C. Transfer of Development Rights Program
The Growth Management Act encourages the use of innovative techniques for land use
management. King County has a long tradition of using innovative techniques, including programs
promoting transfers of development rights, to achieve land management goals such as those stated
above.
To that end, King County promotes the transfer of development rights from land valuable to the
public, especially rural and resource areas, to land better able to accommodate growth. The
Transfer of Development Rights (TDR) Program allows landowners to voluntarily achieve an
economic return on their property while maintaining it in forestry, farming, habitat or parks and
open space in perpetuity. It also increases housing opportunities in the Urban Area where urban
services and infrastructure can accommodate additional growth.
R-212
R-213
R-214
As an innovative means to permanently preserve private lands with
countywide public benefit, to encourage higher densities in appropriate areas
and reduce residential development capacity in Rural Forest Focus Areas,
King County shall continue efforts to implement an effective and focused
transfer of development rights program.
The top priority of the voluntary Transfer of Development Rights Program is
to reduce development in the Rural Area by encouraging the transfer of
development rights from private rural lands into the Urban Growth Area.
Transfers may also be made to rural sites that have RA 2.5 zoning.
King County supports and shall work actively to facilitate the transfer of rural
development rights to:
a. Preserve the rural environment, encourage retention of resource-based
uses and reduce service demands in the Rural Area;
b. Provide permanent protection to significant natural resources; and
c. Increase the regional open space system.
3-13 September 2004
R-215
R-216
R-217
R-218
To promote transfers of development rights, King County shall facilitate the
transfers from private property owners with sending sites to property owners
with receiving sites, buy and sell development rights through the King
County Transfer of Development Rights (TOR) Bank, and work with cities to
develop interlocal agreements that encourage transfers of development
rights into cities and within adopted appropriations. Public amenity funding
to enhance the livability of incorporated area receiving site neighborhoods
accepting increased densities shall also be part of the program. King County
should actively solicit large landowners, within incorporated areas, to
purchase development rights from the TOR bank.
Private properties qualified as sending sites shall provide a permanently
protected area of sufficient size to provide public benefit. Priority candidates
for sending sites are:
a. Lands contributing to the protection of endangered and threatened
species;
b. Rural Forest Focus Areas;
c. Lands that are suitable for inclusion in and provide important links to the
regional open space system; or
d. Agricultural and Forest Production District lands.
Transfers of development rights may be made to receiving sites as follows:
a. Rural areas zoned RA-2.5 may receive transfers of development rights
from the Rural Forest Focus Areas.
b. Unincorporated urban areas and incorporated cities may receive
transfers of development rights. Preferences should be given for
locations within designated urban centers, or adjacent to transit
stations and park and ride lots. Transfers to incorporated areas shall
be detailed in an interlocal agreement between the city and county.
Development Rights Calculations
a. Development rights transferred from Rural Forest Focus Areas to the
Urban Area shall be calculated on a basis of 1 credit for each 5 acres
of site area.
b. If a portion of a sending site is being retained for development, the
subsequent development must be clustered, and the tract preserved
with a permanent conservation easement shall be larger than the
developed portion. In the case of lands within the Rural Forest Focus
Areas, no more than one dwelling unit per 20 acres shall be retained,
and the tract preserved with a conservation easement shall be at least
15 acres in size.
R-219 Following the transfer of development rights from a sending site, a
conservation_easement documenting the transfers shall be recorded and
notice placed on the title of the sending site parcel.
R-220 King County should increase funding for urban area amenties and the TOR
bank and seek private and other public funding to strengthen the TOR
program and facilitate the transfer of development rights from the Rural Area
in order to preserve the rural environment, encourage retention of rural
resource-based uses and avoid urban service demands in the Rural Area.
King County should pursue public or private partnerships and bond or levy
proposals for additional TOR bank funding to target threatened private rural
September 2004 3-14
or resource lands. Rights purchased through such a program could be sold
into any appropriate urban location.
D. Nonresidential Uses
While low-density residential development, farming and forestry are the primary uses in the Rural
Area, some compatible public and private uses are appropriate and contribute to rural character.
Compatible uses might include small, neighborhood churches, feed and grain stores, and home
occupations such as small day care facilities or veterinary services. In addition, it may be
necessary to locate some public facilities in rural areas, such as utility installations that serve rural
homes. Any allowed nonresidential uses should be designed to blend with rural residential
development and resource uses.
R-221
R-222
Nonresidential uses in the Rural Area shall be limited to those that:
a. Provide convenient local services for nearby residents;
b. Require location in a Rural Area;
c. Support natural resource-based industries;
d. Provide adaptive reuse of significant historic resources; or
e. Provide recreational opportunities that are compatible with the
surrounding Rural Area.
These uses shall be sited, sized and landscaped to complement rural
character as defined in policy R-101, prevent impacts to the environment and
function with rural services including on-site wastewater disposal.
Golf facilities shall be permitted when located outside of Rural Forest Focus
Areas, Regionally Significant Resource Areas and Locally Significant Resource
Areas, as a conditional use, in the RA-2.5 and RA-5 zones.
The service area of most schools in the Rural Area is large and relatively sparsely populated.
Placing schools in rural cities or Rural Towns allows them to be served with urban-level utilities
and fire protection and to be used efficiently for other community activities.
R-223
R-224
R-225
In the Rural Area, elementary schools may locate where required to serve
neighborhoods. New middle/junior high schools and high schools and
school facilities are encouraged to locate in rural cities or unincorporated
Rural Towns. In reviewing proposals for middle/junior high and high schools
and school facilities outside rural cities or Rural Towns, King County should
ensure that any approved project will not stimulate local demand for urban-
level services. In order to support the availability of public facilities and
services for educational purposes, public schools and public school facilities
may exceed nonresidential development standards as provided for by county
code, shall comply at a minimum with applicable surface water design
manual standards and may be provided with public sewer services in
accordance with Policy F-249.
Small airfields beyond those already established in the Rural Area should not
be permitted, due to their cumulative impacts on air traffic and nearby uses.
Library services for the Rural Area should be provided by bookmobiles, or by
libraries in Rural Towns or rural cities.
3-15 September 2004
E. Character/Development Standards
The aesthetic qualities and character of the Rural Area depend on a combination of factors, including
low densities; a high ratio of undeveloped or undisturbed soil and natural or crop vegetation to
development, such as roads and structures; historic buildings and landscapes; and minimal
development standards, public facilities and services beyond those needed for environmental
protection and basic public health and safety.
R-226
R-227
R-228
R-229
R-230
New subdivisions in the Rural Area should strive to maintain the size and scale
of traditional development patterns and rural character.
New subdivisions in the Rural Area should be designed and developed to
maximize preservation of existing forest cover and native vegetation, and to
minimize impervious surfaces within individual lots and in the subdivision as
a whole. King County shall develop additional site design standards for new
subdivisions that further reduce the impacts of new homes in the Rural Area
on the natural environment, resource uses and other adjacent land uses.
Site design standards for new subdivisions in the Rural Area should include:
minimization of paved surfaces; limitations on entrance signage;
preservation of natural contours, existing meadows and opportunities for
keeping of horses; and other standards to limit features typical of urban or
suburban development.
Rural residential development adjacent to Agricultural and Forest Production
Districts shall be sited to minimize interference with activities related to
resource uses. Residences next to Forest Production Districts shall be built
with greater setbacks from the Forest Production District boundaries for
safety and to reduce nuisance complaints.
To maintain traditional rural development patterns and assure continued
opportunities for resource activities in the Rural Area, large lot development is
preferred in the Rural Area. Clustering of lots is permitted when:
a. The development provides equal or greater protection of the natural
environment, Natural Resource Lands, historic resources or
archaeological sites;
b. Clusters are limited in size to be compatible with surrounding large lots
or nearby agricultural and forestry uses;
c. The clustered development is offset with a permanent resource land tract
preserved for forestry or agriculture, as designated by the owner at time of
subdivision or short subdivision, or a permanent open space tract. Under
no circumstances shall the tract be reserved for future development; and
d. The development can be served by rural facility and service levels (such
as on-site sewage disposal and rural fire protection).
Low-density development in the Rural Area will have different residential street needs from those in
the Urban Growth Area. Densities and travel demand in the Rural Area are very low and road
maintenance is a proportionately greater per capita cost than in the Urban Growth Area.
Rural streets and roads outside Rural Towns generally will have no more than two travel lanes, no
curbs or sidewalks and feature unpaved shoulders and open drainage ditches. Local access streets
for residential subdivisions will constitute a significant proportion of the site disturbance and
impervious surface associated with new development in the Rural Area and therefore must take the
environment into consideration equally with traffic flow and vehicular access.
September 2004 3-16
R-231 Rural development standards shall be established to protect the natural
environment by addressing seasonal and maximum clearing limits,
impervious surface limits, surface water management standards that
emphasize preservation of natural drainage systems and water quality,
groundwater protection, and resource-based practices. These standards
should be designed to provide appropriate exceptions for lands that are to be
developed for kindergarten through twelfth grade public schools and school
facilities, provided that the school project shall comply at a minimum with the
requirements of the King County Surface Water Design Manual.
F. Sustainable Development
Additional policies on sustainable development are located in Chapter 2.
R-232 King County shall encourage, support and promote the application of
sustainable development practices in all private sector development within
the Rural Area.
G. Low-Impact Development
Current development practices can adversely impact water resources. Low-impact development
(LID) is a new approach to land development that works to match a site's natural hydrologic
function by protecting and enhancing native vegetation and soils, reducing impervious surface and
managing stormwater at the source. These techniques are well suited to development in rural
residential zoned areas.
R-233 King County should work with residential builders and developers to
encourage the use of low-impact development practices that protect native
vegetation and soils and reduce impervious surface. King County should
promote preservation of native vegetation and soils on rural-residential
zoned parcels to the maximum extent practicable. Dispersion of runoff from
impervious surfaces into native vegetation in accordance with the Surface
Water Design Manual should be the preferred method of stormwater
management in the Rural Area.
3·17 September 2004
111. aural Public Facilities and! Service
The policies below set forth King County's general approach to providing services and setting
facility standards for the Rural Area and provide guidance for siting those facilities that require
Rural Area locations. See Chapter Six, Transportation, and Chapter Seven, Facilities and Utilities,
for more detailed policies on specific facilities and services such as roads, on-site sewage
treatment and disposal systems and water supply.
In order to focus growth within the Urban Growth Area, financial resources must be prioritized to
develop and maintain sufficient urban infrastructure and services in the UGA to accommodate
that growth. Further, the presence of a high level of public infrastructure and services has been
demonstrated to create pressure for new growth. For example, the taxpayer-supported road
network constructed in eastern King County over the last twenty to thirty years has been the
greatest source of growth pressure in the rural and natural resources area. To use financial
resources efficiently and reduce growth pressure in the Rural Area, King County will not provide
an urban level of infrastructure and services to the Rural Area. Chapter 6, Transportation and
Chapter 7, Facilities and Utilities, clarify King County priorities for transportation and other facility
improvements in the rural and natural resource areas.
R-301
R-302
King County shall work with cities and other agencies providing services to the
Rural Area to adopt standards for facilities and services in the Rural Area that
protect basic public health and safety and the environment, but are financially
supportable at rural densities and do not encourage urban development.
Public spending priorities for facilities and services within the Rural Area
should be as follows:
a. First, to maintain existing facilities and services that protect public health
and safety; and
b. Second, to upgrade facilities and services when needed to correct level-
of-service deficiencies without unnecessarily creating additional capacity
for new growth.
R-303 In the Rural Area, standards and plans for utility service should be consistent
with long-term, low-density development and resource industries. Utility
facilities that serve the Urban Growth Area but must be located in the Rural
Area (for example, a pipeline from a municipal watershed) should be
designed, and scaled to serve primarily the Urban Growth Area. Sewers
needed to serve previously established urban "islands," rural cities or Rural
Towns or new or existing public schools or public school facilities, shall be
tightlined and have access restrictions precluding service to the Rural Area.
September 2004 3-18
•
IV. Rural Cities, Towns and. Neighborhoods
Rural cities and unincorporated Rural Towns within the Rural Area contribute to variety in
development patterns and housing choices and provide employment opportunities, retail shopping
and other services to nearby residents. These cities and towns also contain a significant portion
of King County's historic architecture and are the primary locations for nonresidential uses in the
Rural Area. Rural King County also contains several small Rural Neighborhoods, which provide
limited, local convenience shopping.
A. Rural Cities
King County's rural cities are incorporated areas whose local governments are involved in the
region's planning processes on an equal legal basis with the suburban cities and Seattle. The
incorporated rural cities are Black Diamond, Carnation, Duvall, Enumclaw, North Bend, Skykomish
and Snoqualmie.
The Growth Management Act stipulates that rural cities and their Urban Growth Areas are to be
treated as part of the Urban Growth Area. The Countywide Planning Policies also provide for urban
land uses and densities and urban services in those locations. Excessive growth in rural cities and
Rural Towns, however, may create pressure for extending urban services (for example, roads)
across the Rural Area or Natural Resource Lands, may increase conversion pressure on nearby
Natural Resource Lands and adversely affect rural character. Therefore, King County views rural
cities as qualitatively different from the Urban Growth Area as a whole, even though they may
provide significant opportunities for residential or employment growth.
King County has worked with the rural cities to establish Urban Growth Areas to accommodate
growth. These areas are shown as part of the Urban Growth Area on the Comprehensive Plan Land
Use Map.
R-401 The rural, incorporated cities and their Urban Growth Areas shall be considered
part of the Urban Growth Area for purposes of planning land uses and facility
needs. King County should work with rural cities to encourage the provision of
affordable housing, to minimize the impacts of new development on the
surrounding rural land and to plan for growth consistent with long-term
protection of significant historic resources, the surrounding Rural Area and
Natural Resource Lands.
R-402 Within Rural City Urban Growth Areas, the following uses shall be permitted
until the area annexes to the city:
a. Residential development at a density of 1 home per 5 acres or less with
mandatory clustering; and
b. Nonresidential development such as commercial and industrial as
determined through previous subarea plans.
B. Rural Towns
Rural Towns are unincorporated towns governed directly by King County, but may provide a focal
point for community groups such as chambers of commerce or community councils to participate
in public affairs.
3·19 September 2004
The purposes of the Rural Town designation are to recognize existing concentrations of higher
density and economic activity in Rural Areas, whether by virtue of historical rural settlements or
redesignation of an urban commercial center; provide a physical focus for the historic identity of
rural communities; and to allow for modest growth of residential and economic uses within these
designations if supported by the community and adequate utilities and other public services are
available.
Although higher-density development in Rural Towns may require public sewers, applying the full
range of urban development standards (e.g. for street improvements or landscaping) may not be
necessary, and may not be consistent with the historic character of these communities. Although
Rural Towns also may in some circumstances develop at densities similar to those in the Urban
Growth Area or in rural cities, they are considered part of the Rural Area for purposes of the GMA,
do not provide significant growth capacity, and are not subject to the growth targets adopted for
the UGA.
R-403
R-404
R-405
King County hereby designates the Rural Towns of Fall City, Snoqualmie Pass
and the Town of Vashon as unincorporated Rural Towns. These historical
settlements in unincorporated King County should provide services and a
range of housing choices for Rural Area residents. The boundaries of the
designated Rural Towns are shown on the Comprehensive Plan Land Use
Map. Adjustments to these boundaries shall only occur through a subarea
planning process, and shall not allow significant increases in development
potential or environmental impacts. No new Rural Towns are needed to serve
the Rural Area.
Commercial and industrial development that provides employment, shopping,
and community and human services that strengthen the fiscal and economic
health of rural communities should locate in Rural Towns if utilities and other
services permit.
Rural Towns may contain higher-density housing than permitted in the
surrounding Rural Area, and should provide affordable and resource-worker
housing if utilities and other services permit. Development density in Rural
Towns may approach that achieved in Rural Cities.
The policies in this section apply only to the unincorporated Rural Towns. King County
encourages rural cities to adopt land use policies and development standards that protect and
enhance their historical character.
R-406 Rural Towns serve as activity centers for the Rural Area and may be served by
range of utilities and services, and may include several or all of the following
land uses, if supported by necessary utilities and other services and if scaled
and designed to protect rural character:
a. Retail, commercial and industrial uses to serve the surrounding Rural
Area population and to provide support for resource industries and
tourism;
b. Residential development, including single-family housing on small lots as
well as multifamily housing and mixed-use developments;
c. Other commercial and industrial uses, including commercial recreation
and light industry; and
d. Public facilities and services such as community services, churches,
schools, and fire stations.
R-407 Sewers may be allowed in Rural Towns if necessary to solve existing water
quality and public health problems which cannot be addressed by other
September 2004 3-20
•
• •
..
methods, provided that any extension of sewer mains from urban areas to
serve a rural town shall be tightlined systems designed to not serve any
intervening lands. All alternatives shall be exhausted before sewers may be
allowed. Rural towns shall not be enlarged to facilitate provision of sewers.
Rural and urban residents alike value the historic character of King County's Rural Towns. New
development can enhance the character and valuable features of Rural Towns through careful
design and location.
R-408 Rural Towns should be compact, promoting pedestrian and nonmotorized
travel while permitting automobile access to most commercial and industrial
uses. New development should be designed to strengthen the desirable
characteristics and the historic character of the town, be supported by
necessary public facilities and services, and be compatible with historic
resources and nearby rural or resource uses. New industrial uses should
locate where they do not disrupt pedestrian or bicycle traffic in established
retail areas of town or conflict with residential uses.
C. Rural Neighborhoods
Rural neighborhoods are small commercial developments, or in some cases, historic towns or
buildings, that are too small to provide more than convenience shopping and services to surrounding
residents. They generally do not have services such as water supply or sewage disposal systems
any different from those serving surrounding rural development. Examples of rural neighborhoods
include the store at Stillwater on the Carnation-Duvall Road, the town of Cumberland on the
Enumclaw Plateau, and Preston .
R-409 The rural neighborhoods designated on the Comprehensive Plan Land Use
Map are small-scale business areas that should provide convenience
shopping and services for the surrounding community. No new rural
neighborhoods are needed to serve the Rural Area. Expansion of the
boundaries of the existing rural neighborhoods shall not be permitted except
through the subarea plan process.
The designated rural neighborhoods shown on the Land Use map are:
Bear Creek:
East King County:
Cottage Lake and Redmond-Fall City Road/236th NE
Greenwater, Baring and Timberlane Village
Cumberland, Krain's Corner and Newaukum
Coalfield and East Renton Plateau
Enumclaw:
Newcastle:
Snoqualmie: Preston and Stillwater
Tahoma/Raven Heights: Maple Valley, Hobart, Ravensdale and North Cedar Grove Road
Burton, Dockton, Tahlequah, Portage, Heights Dock, Jack's Corner,
Vashon Center, Vashon Service Center, Vashon Heights and Maury
Island Service Center
Vashon:
The policies in this section are based on a recognition of the limited size of most rural
neighborhoods, the limited utilities and other services available to them, and a desire to preserve
their existing character and relationship to the surrounding rural community.
R-410 Rural neighborhoods should accommodate only small-scale retail,
community and human services and personal service uses that provide
convenience shopping and services to nearby Rural Area residents. If land
suitable for residential development is included within the boundaries of a
3-21 September 2004
rural neighborhood, it should be zoned for rural residential development
consistent with the residential development policies of this plan.
R-411 King County should adopt commercial development standards for rural
neighborhoods that facilitate economic reuse of existing structures, minimize
increases in impervious surfaces and encourage retention of historic
character and scale. Urban-level parking, landscaping and street
improvement standards are not appropriate for Rural Neighborhoods.
D. Nonresource Industrial Uses and Development Standards in the
Rural Area
There are two existing industrial areas in the Rural Area containing multiple industrial uses on
several sites. One is located within the southwest portion of the Town of Vashon and the second
is a designated industrial area adjacent to the rural neighborhood of Preston. The Preston
Industrial Area recognizes an existing concentration of industrial uses that contributes to the
economic diversity of the Rural Area, but expansion of this industrial area beyond the identified
boundaries is not permitted (see policy C-941 ).
R-412 New industrial uses in the Rural Area shall be permitted only in Rural Towns
and in the designated industrial area adjacent to the Rural Neighborhood of
Preston.
In order to preserve rural character and protect sensitive natural features, new rural industrial
development needs to be of a scale and nature that is distinct from urban industrial development.
The scale and intensity and many of the uses allowed in urban industrial development are not
appropriate for rural industrial areas. The following policy applies to all new industrial development in
the Rural Area.
R-413 Development regulations for nonvested industrial development in the Rural
Area shall require the following:
a. Greater setbacks, and reduced building height, floor/lot ratios, and
maximum impervious surface percentage standards in comparison to
standards for urban industrial development.
b. Maximum protection of sensitive natural features, especially salmonid
habitat and water quality.
c. Building and landscape design that respects the aesthetic qualities and
character of the Rural Area, and provides substantial buffering from the
adjoining uses and scenic vistas.
d. Building colors and materials that are muted, signs that are not internally
illuminated, and site and building lighting that is held to the minimum
necessary for safety.
e. Heavier industrial uses, nonvested industrial uses producing substantial
waste byproducts or wastewater discharge, or nonvested paper, chemical
and allied products manufacturing uses in the urban industrial zone shall
be prohibited.
f. Industrial uses requiring substantial investments in infrastructure such
as water, sewers or transportation facilities shall be scaled to avoid the
need for public funding of the infrastructure.
The intent of this policy is to preclude expansion of the industrial area beyond the identified
boundaries and to ensure that new development (not previously constructed or vested) in the
industrial area meets rural character standards. Site design, landscaping, design and construction of
September 2004 3-22
• •
•
internal and access roads and building scale should reinforce the set boundaries and rural nature of
the industrial area to further discourage future industrial expansion beyond the industrial boundary.
There are also existing, isolated industrial sites in the Rural Area which are recognized, but are
not appropriate for new industrial uses. Further expansion of these isolated industrial uses is not
encouraged, and therefore they are not zoned Industrial.
R-414 Existing industrial uses in the Rural Area outside of Rural Towns or the
designated industrial area adjacent to the Rural Neighborhood of Preston
shall be zoned rural residential but may continue if they qualify as legal,
nonconforming uses .
3·23 September 2004
V~. Resource Lands
Ensuring Conservation and Productive Use of Natural Resource Lands
King County's Natural Resource Lands are those with long-term commercial significance for
farming, forestry, and minerals. Products from Natural Resource Lands play an important role in
our economy by providing jobs and raw materials such as food, wood, and gravel, and by
providing links to our cultural heritage. Responsible stewardship of resource lands produces
multiple environmental benefits, such as:
• Stream and salmon protection;
• Clean air and water;
• Wildlife habitat;
• Flood prevention; and
• Groundwater recharge.
Historically, Natural Resource Lands have been poorly protected. For example, only about one-
third of the farmland existing in 1945 remains today. The natural resource land base has
diminished for many reasons, among them:
• Demand for more land for industrial, commercial, and residential structures;
• Lack of understanding of natural resource value;
• Inconsistent coordination between agencies;
• Poor operational practices in some cases; and
• Lack of an adequate means to compensate natural resource owners for the many
non monetary values their lands provide.
Due to this history, King County has taken major steps to conserve and manage agricultural soils
and activities, forestry and mining opportunities. Natural Resource Lands and the industries they
support are conserved by encouraging development to occur primarily in the Urban Grow1h Area
as envisioned by the GMA, which requires new development to be focused primarily in the Urban
Grow1h Area. Under this plan, Natural Resource Lands, including designated Agricultural
Production Districts, the Forest Production Districts and sites of long-term commercial
significance for resource uses, will have minimal new residential and commercial development.
New development that does occur will be designed to be compatible with active resource-based
uses.
This chapter contains King County's strategy for conservation of these valuable Natural Resource
Lands and for encouraging their productive and sustainable management. The strategy consists
of policies to guide planning, incentives, education, regulation and purchase of development
rights.
Forest, farm and mineral lands are not King County's only natural resources. Many other
resource-based industries, such as the fisheries industry, are influenced by King County's land
use and planning policies. Policies for the protection and enhancement of air, water, vegetation,
fisheries, wildlife and other natural resources can be found in Chapter Four, Environment.
The Rural Forest Commission was established in 1997 to represent the diversity of forest
interests in King County. The Commission reviews the development and implementation of
strategies, programs, policies and regulations that benefit forestry and advises the county on ways
to preserve rural forests and promote rural forestry.
September 2004 3-24
R-501 The Rural Forest Commission shall advise the King County Executive and
Council on the development of innovative programs, policies and regulations
that benefit forestry and that encourage the retention of the forest land base
in King County. King County shall continue to support the Rural Forest
Commission with staff and other resources.
In 1994, the Agriculture Commission was established as a forum for farmers to take an active role
in land use decisions, policies and regulations affecting commercial agriculture. The commission
solicits input from agricultural agency technical advisors and others with land use and technical
expertise, as well as other affected groups such as the Dairy Federation, Native American Tribes,
and project proponents.
R-502 The Agricultural Commission shall advise the King County Executive and
Council on agricultural issues and programs, including, but not limited to:
a. Existing and proposed legislation and regulations affecting commercial
agriculture;
b. Land use issues as they impact agriculture; and
c. Ways to maintain, enhance and promote agriculture and agricultural
products in the region.
King County shall continue to support the Agricultural Commission with staff
and other resources.
A. Resource Conservation Strategy
In 1985, the King County Comprehensive Plan designated five Agricultural Production Districts
and the Forest Production District. Subsequent planning efforts established minimum lot sizes
and uses for these districts and their surrounding areas. These land use regulations are
consistent with the requirements of the GMA to designate productive lands and to plan for
adjacent and nearby land uses compatible with long-term commercial farming and forestry.
Provisions for extraction of mineral resources are also included, consistent with the requirement of
GMA.
GMA requires designation of agricultural and forest lands of long-term commercial significance.
Agricultural lands of long-term commercial significance are designated as Agricultural Production
Districts and forest lands of long-term commercial significance are designated as the Forest
Production District as shown on the Agricultural and Forest Lands Map.
The GMA also requires designation of mineral resource lands that have long-term significance for
the extraction of minerals. Such lands are shown as Designated Mineral Resource Sites on the
Mineral Resources Map in this chapter. The role of the Forest Production District in the
conservation of mineral resources is also explained below.
R-503
R-504
R-505
King County shall promote and support forestry, agriculture, mining and
other resource-based industries as a part of a diverse, regional and
sustainable economy.
Well-managed forestry and agriculture practices are encouraged because of
their multiple benefits, including natural resource protection.
Farm lands, forest lands and mineral resources shall be conserved for
productive use through the use of Designated Agriculture and Forest
Production Districts and Designated Mineral Resource Sites where the
principal and preferred land uses will be commercial resource management
3-25 September 2004
R-506
R-507
activities, and by the designation of appropriate compatible uses on adjacent
rural and urban lands.
Land uses, utilities and transportation facilities adjacent to Designated
Agriculture and Forest Production Districts and Designated Mineral Resource
Sites, shall be sited and designed to ensure compatibility with resource
management.
King County should facilitate the siting of industries, infrastructure and
services that serve and are served by resource-based industries in close
proximity to designated Agriculture and Forest Production Districts and
Designated Mineral Resource Sites when adverse impacts and
incompatibilities can effectively be mitigated.
Conflicts with surrounding land uses and environmental problems can arise even with the best of
precautions. Resource-based industries need reasonable certainty that operations can continue if
activities are performed in an environmentally sound manner.
Forest lands and farms provide valuable materials and employment as well as other important
functions and values, such as community character, open space and wildlife habitat. These
benefits are not without associated costs. Owners of Natural Resource Lands make substantial
investments in managing their land. Taxes, fees, labor costs, costs associated with vandalism
and market uncertainties can adversely affect the profitability of resource-based industries.
Two tax incentive programs exist to encourage continued farm and forest management both
within and outside the Forest Production District and Agriculture Production Districts: the
Washington State Timber and Forest Lands Program (chapter 84.33 RCW), and the Open Space
Tax Program (chapter 84.34 RCW).
R-508
R-509
King County should expand access to preferential tax programs to encourage
landowners to continue practicing farming and forestry and to help ensure
retention of the resource land base. Preferential tax programs for resource
uses should be publicized and marketed. Preferential tax programs applied to
resource lands are indicative that the investment expectations of the owners
are for the lands to be productive as resource lands. The effectiveness of
these programs should be monitored and the programs modified as needed.
King County shall employ a variety of innovative programs and incentives,
tailored to the specific needs of each resource-based industry, to help
maintain and enhance resource-based industries.
Examples of such techniques could include implementation of a Transfer of Development Rights
program, technical assistance and education for sustainable land management, expanded education
for urban and suburban residents, expanded purchases of land or development rights, the purchase
of scenic easements and other less-than-fee-ownership interests which conserve resource uses,
establishment of buffers and setbacks for adjacent properties and relief from special levies and local
improvement district fees.
When urban development occurs near Natural Resource Lands, conflicts can result. Examples of
such conflicts are greater risk of forest fires, vandalism to logging, farm and mining equipment,
destruction of young trees and increased mixing of heavy truck and residential traffic, which
present safety problems. For these reasons, resource management in or near developed areas
often is more costly.
September 2004 3-26
)
R-510 King County should develop and employ effective means to inform affected
property owners about nearby resource management activities. This may
include, but not be limited to:
a. Notice on title for properties within five hundred feet of designated
agriculture, forestry, and mining lands:
b. Signage for the Agricultural Production District, Forest Production
District, Rural Forest Focus Areas; and
c. Community meetings, and other public notification tools.
Natural Resource Lands in King County include privately owned lands in unincorporated areas as
well as lands owned and/or managed by city, state and federal agencies and tribes. In addition, a
variety of state and federal regulations apply to some resource maintenance, harvesting and
extraction operations. Resource conservation efforts, therefore, require a regional perspective
and intergovernmental cooperation.
R-511
R-512
R-513
R-514
King County shall work cooperatively with cities, federally recogpized tribes,
other public agencies, private utilities, resource managers, land owners and
citizens to conserve public and private Natural Resource Lands for long-term
productivity and environmental protection in a consistent and predictable
manner.
Designated Forest and Agricultural Production District lands shall not be
annexed by cities.
King County should establish written agreements with agencies, tribes and
other affected parties whose close coordination and collaboration are
essential to effective implementation of resource management programs.
Such agreements should serve to establish consensus and commitment to
achieving specific resource management goals and to define the specific
roles and responsibilities of each agency.
King County should avoid duplication of federal and state regulations that
apply to resource-based industries. However, King County reserves the
authority to address issues of local concern with regard to resource-based
activities and operations.
A resource management strategy that protects the environment is necessary to maintain the long-
term productivity of the resource. Chapter Four, Environment, describes the value of using an
integrated, ecosystem-based approach to natural resource and environmental planning and
management. This approach, along with sound operational practices by resource-based
industries may be able to prevent or minimize environmental impacts associated with resource
harvesting and extraction.
R-515
R-516
Resource-based industries should use practices that protect the long-term
integrity of the natural and built environment, adjacent land uses, and cultural
resources that maintain the long-term productivity of the resource base.
Resource industry practices should result in maintenance of ecosystem health
and habitat.
Habitat protection requirements should not fall disproportionately on land
maintained in agriculture or forestry, and the costs of such protection shall
not be disproportionately placed on the owners of such land.
3-27 September 2004
R-517
R-518
King County should be a leader in resource management by demonstrating
environmentally sound agriculture and forestry on county-owned land.
King County shall provide for integrated resource education through trail and
sign systems linked with working farms, forests, and mines. Interpretation
should:
a. Provide historical perspective;
b. Demonstrate current adaptive resource management practices (forestry,
fisheries, wildlife, agriculture); and
c. Explain economics of various resource uses.
B. Forestry
King County forestlands provide local, regional and national benefits that are basic to our quality of
life. In addition to supplying a variety of wood and other products, forests emit oxygen, supply
pure water, control flooding and soil erosion, enhance groundwater recharge, provide habitat for
innumerable plant and animal species and offer scenic vistas and recreational opportunities. King
County's forests provide employment in wood, paper, recreation, tourism and fishing industries.
In sum, properly managed forests are fundamental to a healthy, diverse economy and
environment.
The growth in human population has resulted in the loss of forestlands through conversion to
nonforest uses. Increasing demands are being placed upon the remaining forest land base to
provide goods, recreational opportunities and ecological functions. To address these challenges,
forest managers are embracing more broad-based management methods and strategies that
encompass ecosystems, landscapes and watersheds, while continually incorporating new
scientific information to improve these approaches. Their efforts, together with the collective
foresight and dedication of landowners, interest groups, tribes, citizens and agencies, are needed
to ensure that King County's forests continue to contribute to a sustainable way of life for present
and future generations.
The first step to maintain and enhance the commercial forest industry is to protect the forest land
base. Second, an ecosystem approach to forest management that provides for long-term
ecosystem health and productivity and addresses cumulative impacts on nontimber resources
should be explored. Third, commercial forestry must be supported and encouraged by minimizing
land use conflicts and offering incentives. Finally, forestland conversions that do occur must be
managed to minimize environmental degradation.
1. Protecting Forest Lands
The purpose of the Forest Production District is to prevent intrusion of incompatible uses, manage
adjacent land uses to minimize land use conflicts and prevent or discourage conversion to
nonforestry-based uses. A comparison of the area of forestland converted since 1987 inside the
Forest Production District with the area converted outside the district indicates that landowners
inside the Forest Production District are committed to long-term forestry. It also indicates that
designation and zoning of commercial forest lands help to discourage subdivision and conversion.
Sixty percent of the land area in King County is within the designated Forest Production District
(FPD). The FPD comprises 1,300 square miles (825,000 acres) of forestland in east King County.
About 70% of the FPD is in public ownership: parts of the Alpine Lakes Wilderness Area, Mt.
Baker-Snoqualmie National Forest, state and county parks, Washington State Department of
Natural Resources, and watersheds for the cities of Seattle and Tacoma.
Commercial forestry is conducted on approximately 250,000 acres in private ownership and on
another 277,000 acres of state and federal forestlands. Most of this land is held in large
September 2004 3-28
contiguous blocks. At this larger scale, it is easier to manage for multiple purposes such as
habitat and long-term forest health.
R-519
R-520
The Forest Production District is comprised of and shall remain in large
blocks of contiguous forest lands where the primary land use is commercial
forestry. Other resource industry uses, such as mining and agriculture,
should be permitted within the Forest Production District when managed to
be compatible with forestry.
The Forest Production District is a long-term designation. Lands may be
removed from the Forest Production District only through a subarea planning
process, and only to recognize areas with historical retail commercial uses.
The policies in this section allow for very limited residential uses in the designated Forest
Production District, consistent with the objective of continuing forestry as the primary land use.
For example, residences may be appropriate to permit forest mangers to live on their land. King
County zoning and subdivision regulations establish a large parcel size to promote efficient forest
operations and to reduce incompatible residential development. Although the zoning calls for an
BO-acre minimum lot size, many smaller lots were created prior to application of the zoning.
Proliferation of residences in the FPD makes commercial forestry less viable.
R-521
R-522
R-523
King County is committed to maintaining working forestland in the FPD, and
shall continue to work with landowners and other stakeholders to promote
forestry, reduce uses and activities that conflict with resource uses and
recognize forestland values.
To reduce conflicts with resource uses, a forest management plan shall be
required as a condition of development for any residential uses. Accessory
dwelling units shall not be allowed in the FPD.
Structures within the Forest Production District should be sited to maintain
the productivity of the district. Site plan requirements should limit
impervious surface, provide for fire control, protect domestic water supply
and prevent conflicts with forest management.
King County can further protect commercial forestlands and prevent conflicts by working with
other public agencies and service providers to consolidate lands and to locate infrastructure
facilities to prevent or minimize intrusions. Such actions can also improve the owner's capacity to
protect fish and wildlife habitat and other natural resources.
R-524
R-525
In consultation with federally-recognized tribes and other affected agencies
and landowners, King County should support land trades that result in
consolidated forest ownership and work with forest managers to identify and
develop other incentives for continued forestry.
King County opposes the establishment or expansion of special purpose
taxing districts and local improvement districts in the Forest Production
District, and shall not grant new or expanded franchises for utilities in the
Forest Production District, unless demonstrated that they directly benefit
forestry or are necessary for trasmission of power or water.
Forest lands have tremendous recreational and aesthetic value. For example, Forest Production
District lands are included within the Mountains-to-Sound Greenway along the 1-90 corridor.
Opportunities for hiking and other forms of outdoor recreation exist within the working forests that
are part of the Greenway. (This concept is described in more detail in Chapter Four,
Environment, and Chapter Five, Parks, Open_Space and Cultural Resources.) Access to Natural
3-29 September 2004
Resource Lands must be carefully managed, however, to prevent conflict with natural resource
goals. For example, open gate policies allowing public access may be incompatible with fish and
wildlife protection goals and sometimes may interfere with forestry operations by allowing such
activities as garbage dumping, vandalism and timber theft.
R-526 Public and private forest owners are encouraged to provide for recreational,
educational and cultural uses when compatible with forest protection.
Recreational and institutional developments, such as conference centers, ski areas and
associated hotels, allow more people to enjoy the aesthetic benefits of forest lands. Such facilities
are acceptable if located in areas of existing development, such as Snoqualmie Pass, and their
operation and use are restricted adequately to minimize conflict with resource lands. Major
recreational or institutional development sites can adversely affect the Forest Production District
because they reduce the forest land base and conflict with other resource management goals.
R-527 No master planned resorts shall be permitted in the Forest Production
District. New or expansion of existing recreational or institutional uses in the
Forest Production District may be permitted if compatible with long-term
forestry, interests of federally-recognized tribes and other resource
management goals.
Adverse environmental impacts associated with forest practices have the potential to heal over
time, whereas those associated with development are usually irreversible. For this reason, forest
lands being converted to nonforest uses must be held to higher land clearing and grading
standards than those that apply under the Forest Practices Act must be used, for example, to
protect surface and groundwater quality and quantity, control stormwater runoff and minimize
damage to fish and wildlife habitat.
When applying for a forest practice permit, a landowner must state whether the land is to be
retained in forest use or converted to a nonforest use. The Forest Practices Act, as amended in
1997, requires local jurisdictions to impose a six-year development moratorium on any properties
for which the forest practice application did not state the intention to convert to a nonforest use,
unless the application contains a conversion option harvest plan approved by the local jurisdiction.
R-528 King County shall impose a six-year development moratorium for landowners
who do not state their intent to convert at the time of Forest Practice
Application or who do not harvest the site according to a King County
approved Conversion Option Harvest Plan. King County shall develop a list
of allowable exceptions from the.development moratorium and shall ensure
that potential buyers of properties subject to the moratorium are alerted to
the moratorium.
Landowners choosing to convert their land to nonforest uses also must state their intent on the
Forest Practice Application and, as provided in the Forest Practices Act, must conduct their forest
practices according to applicable local government regulations. If a landowner intends to convert
their land to a nonforest use, they must submit a Forest Practices Application to King County and
meet all King County standards.
R-529 King County should continue to work with all affected parties and the
Washington Department of Natural Resources to improve the enforcement of
forest practice regulations in the urban and rural areas, and to ensure that
landowners comply with county regulations when they are converting
portions of the site to a nonforest use. Harvesting of forest lands for the
purpose of converting to nonforestry uses shall meet all applicable county
standards for clearing and sensitive areas management.
September 2004 3·30
2. Promoting Forest Management
King County has worked with state, federal, and private landowners on multiparty resource plans,
such as the Middle Fork Snoqualmie Plan, the plan for Rattlesnake Ridge, and numerous
watershed planning efforts. There will continue to be opportunities for interagency cross-
ownership cooperation, which will result in improved resource management and conservation.
R-530
R-531
R-532
R-533
Working with public and private forest land managers, King County shall
encourage long-term forest productivity and the protection of land and water
resources by participating in collaborative, multiownership planning efforts.
King County promotes forest management that achieves long-term forest
health, protection of watersheds, sensitive areas and habitat to support fish
and wildlife populations, protection of threatened and endangered species,
and preservation and economic viability of working forests.
King County should work with the King County Rural Forest Commission to
conduct a demonstration project for tree removal to reduce fire hazard in the
Rural Area. The demonstration project should allow for a community based
project in a carefully selected area using best management practices.
King County shall encourage the development of private/public partnerships
that provide incentive for landowners to practice innovative, fish-friendly
forestry and that can help ensure retention of the forest resource land base in
perpetuity.
An example of such a partnership is the Mountains-to-Sound Greenway Biosolids Forestry
Program, which includes King County, Washington State Department of Natural Resources, the
Greenway Trust, the University of Washington and the Weyerhauser Company. One of the
elements of this program involves the acquisition of forestlands that are vulnerable to residential
and commercial development. Lands are acquired by a combination of county funds and federal
Forest Legacy funds and then transferred to the State DNR for management. By deed, these
lands stay in forest resource use in perpetuity and are managed according to the state's Habitat
Conservation Plan. Seventy-five percent of all revenues generated are returned to King County.
The lands that have been acquired help to form the block of public ownership along 1-90, providing
wildlife corridors, opportunities for trails and recreation, and the water quality protection provided
by forest cover.
In addition to landscape-level planning and analysis, resource managers should identify specific
areas in their forest ownership that are degraded or negatively impacting aquatic resources.
Examples of such areas are logging roads or gravel mines no longer needed and scheduled to be
abandoned or riparian zones that are not sufficiently vegetated. Organic soil amendments, when
properly used, can greatly enhance vegetative growth and restore productivity to these sites, thus
protecting fish and other aquatic resources. The use of recycled organic wastes generated in
King County closes the recycling "loop" and helps us sustain the productivity of our resource
lands.
R-534 King County encourages the use of recycled, organic-based soil amendments
and fertilizers in forest ecosystems, which can reduce erosion and
sedimentation into streams, increase water-holding capacity of soils,
stimulate the growth of trees and other vegetation and enhance fish and
wildlife habitat. King County shall work with the general public and private
and public forestland owners to encourage the selective and appropriate use
of these materials for ecosystem enhancement and restoration.
3-31 September 2004
One of the most successful efforts already underway is the use of the county's biosolids to fertilize
public and private forests and the use of biosolids compost to help restore old logging roads in the
Mountains-to-Sound Greenway in eastern King County. Volunteers from many local youth and
environmental groups, including Earthcorp, are involved in this program, which involves removal
of the logging roads, restoration of the natural slope of the land, and the use of compost to speed
vegetation growth.
C. Agriculture
Land suitable for farming is an irreplaceable natural resource. Since 1959, almost 60 percent of
King County's prime agricultural land has been lost to urban and suburban development. Of
100,000 acres available for farming 40 years ago, today only 42,000 acres remain in agriculture.
Fortunately, the amount of agricultural land has stabilized due, in large part, to a variety of county
policies and initiatives to conserve these commercially viable resource-based lands.
Agricultural lands and farming provide many benefits to the citizens of King County including
scenic open space, a connection to our cultural heritage, fresh local foods and a diverse
economy. In 2002, farmers in King County produced over $94 million in agricultural sales.
Commercial agricultural production, however, has declined by 30 percent in gross sales since
1978.
This section focuses on the county's efforts to maintain and enhance commercial agriculture for
the value of local produce, dairy products, keeping livestock and for scenic and historic values. To
meet the GMA requirement to maintain and enhance agriculture, a variety of methods and
programs continue to be necessary. The policies call for King County to:
• Protect productive farmland by designation and zoning
• Limit development to uses that are necessary to support commercial agriculture;
• Prevent or minimize land use conflicts between farming operations and adjacent land uses;
• Allow necessary infrastructure (markets, water, affordable housing, supply stores, technical
services, tax incentives) that supports commercial agriculture; and
• Encourage farming practices that conserve soils and protect water quality, fisheries and
wildlife.
1. Protecting Agricultural Lands
In 1979, voters approved a $50 million ballot measure to protect farmland threatened by
development. The Farmland Preservation Program (FPP) became the first voter-approved
measure in the nation to protect farmland in a metropolitan area. By purchasing the development
rights, the FPP keeps farmland open and available through covenants that restrict development
and limit the properties' uses exclusively for agriculture and open space. The covenants "run with
the land" in perpetuity so the land is 'protected regardless of ownership. Under the FPP, the
county owns the development rights: however, the lands remain in the private ownership of over
200 property owners. The county cannot sell or remove its interest in FPP lands with the
exception of conveying public road or utility easements.
In 1995, the county approved an additional $3 million to the purchase of additional development
rights under the Farmland Preservation Program. In October 1999, the county formally
recognized the 20th anniversary of the Farmland Preservation Program and its success to date in
preserving over 12,800 acres of farmland for the generations of today and tomorrow.
R-535 King County shall continue to implement the objectives of the Farmland
Preservation Program. Protection of property purchased under the FPP shall
September 2004 3-32
be a high priority when balancing conflicting interests such as locating
transportation, active recreation or utility facilities.
Agriculture is most productive in agricultural communities where neighbors support agriculture,
where parcels are large enough for commercial agriculture and where labor, supplies and markets
for farm products are available. King County's farm soils and most profitable farms are usually
found in contiguous blocks with few nonagricultural uses. In 1985, King County established
Agricultural Production Districts (APDs) with large lot zoning and specifying agriculture as the
preferred use in these areas.
The Agricultural Production Districts, shown on the Agriculture and Forest Lands Map in this
chapter, present the least number of land use conflicts for agriculture, contain agricultural support
activities and provide the best environment for farming in King County. The five Agricultural
Production Districts are: _the Sammamish Valley, the Snoqualmie Valley, the Lower Green River
Valley, the Upper Green River Valley and the Enumclaw Plateau. Most of the farmlands
preserved under the FPP are found in these APDs.
R-536
R-537
Agricultural Production Districts are blocks of contiguous farmlands where
agriculture is supported through the protection of agricultural soils and
related support services and activities. Roads and natural features are
appropriate boundaries for Agricultural Production Districts to reduce the
possibility of conflicts with adjacent land uses.
King County should purchase additional development rights to farmland in
the Agricultural Production Districts as funding becomes available.
Livestock, dairy and large-scale commercial row-crop operations require large parcels of land to
allow for production which is profitable and sustainable. Generally, 35 acres is needed for full-
time wholesale commercial production of such products. Specialty agricultural products, products
that are direct-marketed and part-time farming enterprises generally need less acreage to be
profitable.
R-538
R-539
R-540
R-541
All parcels within the boundaries of an APD should be zoned Agricultural,
either A-10 or A-35. If small parcels in the APD are not zoned for Agriculture,
permitted nonresidential uses must not conflict with agricultural uses in the
APD.
Lands within Agricultural Production Districts should remain in parcels large
enough for commercial agriculture. A residential density of one home per 35
acres shall be applied where the predominant lot size is 35 acres or larger,
and a residential density of one home per 10 acres shall be applied where the
predominant lot size is less than 35 acres.
Agriculture should be the principal land use in the Agricultural Production
Districts. Permanent new construction within districts shall be sited to
prevent conflicts with commercial farming or other agricultural uses, and
nonagricultural uses shall be limited. New development shall not disrupt
agriculture operations and shall have a scale compatible with an active
farming district.
On-site housing for farm employees shall be allowed where this can be
accomplished without unnecessarily removing land from agricultural use or
conflicting with other public interests. King County should develop
guidelines to allow on-site housing for farm employees, including guidelines
3.33 September 2004
that account for the restrictive covenants on properties in the Farmland
Preservation Program.
Some of the highest quality salmon habitat in King County is found within Agricultural Production
Districts (APDs). Additional protection or restoration of critical habitat within the APDs is likely to
be recommended by Water Resources Inventory Area Salmon Conservation Plans. Protection
and enhancement of existing salmon habitat is a resource based land use that should be included
in all farm management plans. Specific habitat protection rules should not jeopardize the
agricultural productivity within the APD. Aquatic habitat restoration or wetland mitigation projects
should be limited in scale to achieve the objectives of the project while limiting fragmentation of
farms and aquatic habitat. Many habitat restoration projects can be designed in a manner that
provides benefits to both fish habitat and the agricultural landowner.
R-542
R-543
Aquatic habitat restoration projects or floodplain restoration projects are
allowed on agricultural lands that are unsuitable for direct agricultural
production purposes, such as portions of property that have not historically
been farmed due to soil conditions or frequent flooding, and which cannot be
returned to productivity by drainage maintenance, or where the proposed
project would result in a net benefit to agricultural productivity. Agriculture
must remain the predominant use in the APDs and these projects shall not
reduce the ability to farm in the area. Such projects may only be allowed on
agricultural lands when there are no other suitable lands available and the
project is supported by landowners who would be impacted by the project
and when:
a. The project is included in an approved Water Resources Inventory Area
Plan, Farm Management Plan, Flood Hazard Reduction Plan or other
functional plan; or
b. The project would improve agricultural productivity within the APD.
Maintaining the viability of farmlands is a high priority for King County.
Within the Agricultural Production Districts, measures to protect threatened
or endangered species shall be tailored to ensure working farms can
continue to operate.
Two Agricultural Production Districts (APO) in or near urban areas, the Lower Green River Valley
and Sammamish Valley, were designated in the 1985 Comprehensive Plan, and those
designations have been retained. The development rights from many, but not all, of the parcels in
these two districts have been purchased through the Farmlands Preservation Program. The
Lower Green APO is completely surrounded by urban designated land and as such, functions as
both prime agriculture land and urban separator.
R-544
R-545
King County commits to preserve Agricultural Production District parcels in
or near the Urban Growth Area because of their high production capabilities,
their proximity to markets, and their value as open space.
The Lower Green River Agricultural Production District is a regionally
designated resource that is to remain in unincorporated King County. The
Lower Green River Agricultural Production District functions as an urban
separator between the cities of Kent and Auburn. King County may contract
with other jurisdictions to provide some local services to this area as
appropriate.
Parks and farms are not necessarily good neighbors, since park users can trespass and damage
crops, animals and farm equipment. Recreation near and within districts can be planned to
prevent trespass. For example, a park located across a river or ravine from an Agricultural
September 2004 3-34
Production District (APO) or a farm would have a pleasant view of farmland without encouraging
trespass.
R-546 Active recreational facilities should not be located within Agricultural
Production Districts. When new parks or trails are planned for areas within
or adjacent to Agricultural Production Districts, King County should work
with farmers to minimize impacts to farmland and agricultural operations.
Public road and utility projects within and through Agricultural Production Districts must be
designed to prevent disruption to agriculture. For example, roads shall have adequate shoulders
and signs to protect farm equipment and alert faster vehicles to the presence of farming activity.
Therefore, road and utility district capital facilities and plans, including water, waste water and
drainage, need to ensure that services are consistent with preservation of long-term agriculture.
(Chapter Eight, Facilities and Services, contains policies requiring special district plans to be
consistent with land use plans.)
R-547
R-548
Public services and utilities within and adjacent to Agricultural Production
Districts (APDs) shall be designed to minimize significant adverse impacts on
agriculture and to maintain total farmland acreage and the area's historic
agricultural character:
a. Whenever feasible, water lines, sewer lines and other public facilities
should avoid crossing Agricultural Production Districts. Installation
should be timed to minimize negative impacts on seasonal agricultural
practices; and
b. Road projects planned for the Agricultural Production Districts including
additional roads or the widening of roads should be limited to those
needed for safety and which benefit agricultural uses. Where possible,
arterials should be routed around the APDs. Roads that cross APDs
should be aligned, designed and maintained to minimize negative
impacts on agriculture, and to support farm traffic; and
c. In cases when public or privately owned facilities meeting regional needs
must intrude into Agricultural Production Districts, they should be built
and located to minimize disruption of agricultural activity.
Lands can be removed from the Agricultural Production Districts only when it
can be demonstrated that:
a. Removal of the land will not diminish the productivity of prime
agricultural soils or the effectiveness of farming within the local APD
boundaries; and
b. The land is determined to be no longer suitable for agricultural purposes.
In addition to meeting these two tests, removal of the land from the APD may
only occur if it is mitigated through the addition of agricultural land abutting
the same APD of equal acreage and of equal or greater soils and agriculture
value.
2. Sustaining Agriculture and Farming
King County has made a significant investment in preserving farmland for agriculture and open
space uses. The next step is to help existing and future farmers maintain and operate their farms
and inform consumers and businesses, such as restaurants, of the benefits of locally grown
foods. In order to further maintain and enhance commercial farming on small farmland parcels,
farmers and prospective farmers must have access to information on marketing and production
strategies for small acreages, the potential for specialty crops and sustainable farming
techniques.
3-35 September 2004
R-549
R·550
R·551
R-552
King County shall work with and provide support to the work of Washington
State University Cooperative Extension for technical and marketing
assistance for small·scale commercial farmers.
King County shall continue to support innovative initiatives, such as the
Puget Sound Fresh and Farm Link Programs, to promote and enhance
agriculture in King County.
The county should develop specific incentives to encourage agricultural
activities in the remaining prime farmlands located outside the Agricultural
Production District. These incentives could include tax credits, expedited
permit review, reduced permit fees, permit exemptions for activities
complying with best management practices or similar programs.
King County shall develop an Agricultural Building Permit with an expedited
review process and reduced fees for structures necessary for farm
operations.
King County recognizes the importance of adding value to and direct sales of agricultural products
as a way to keep agriculture viable in an urban landscape. King County's agriculture program
works with farmers to encourage them to add value to their products by processing, packaging,
and selling them directly to the consumer.
R-553 Agricultural processing, packing and direct sales are considered agricultural
activities and should be allowed at a size and scale appropriate to the zone in
which they are operating. King County shall work with local and state health
departments to develop regulations supporting these activities.
Agricultural practices modify the natural environment in order to produce food or fiber or maintain
livestock for human use. Ideally, practices that maintain the productivity of the lands also protect
environmental quality. Farmers, technical advisors and environmental regulators must work
together to understand the relationships between production practices, environmental protection
and profitability. These practices, referred to as best management practices, are designed to
prevent erosion, retain riparian vegetation, avoid stream bank collapse, properly dispose of animal
wastes, safely use and dispose of pesticides and prevent excessive suriace water runoff.
R-554 King County shall provide incentives, educational programs and other
methods to encourage agricultural practices which maintain water quality,
protect public health, protect fish and wildlife habitat, protect historic
resources and prevent erosion of valuable agricultural soils while
maintaining the functions needed for agricultural production.
D. Mineral Resources
King County contains many valuable mineral resources, including deposits of coal, sand, rock,
gravel, silica, peat, clay, metallic ores and potentially recoverable gas and oil. Mining and
processing these deposits is an important part of King County's economy, currently providing
hundreds of jobs and producing materials used locally, regionally and nationally. Mining also has
historic significance, in that it provided the impetus for past development in many parts of King
County, including Black Diamond and the Newcastle area.
King County is required by the State Growth Management Act to designate and conserve mineral
lands. In doing so the county must assure that land uses adjacent to mineral lands do not
interfere with the continued use of mineral lands in their accustomed manner and in accordance
September 2004 3-36
•
with best management practices. The policies in this section explain the steps taken to designate
and conserve mineral resource lands and provide direction on the comprehensive review needed
before additional sites are designated for mineral resource extraction.
Four main steps are necessary to maintain and enhance commercial mineral resource industries.
First, mineral resource sites should be conserved through designation and zoning. Second, land
use conflicts between mining, processing and related operations and adjacent land uses should
be prevented or minimized. Third, operational practices should protect environmental quality,
fisheries and wildlife, in balance with the needs of the industry. Finally, mining areas need to be
reclaimed in a timely and appropriate manner.
The Mineral Resources Map identifies four different types of Mineral Resource Sites. The sites
were identified in the 1994 King County Comprehensive Plan or in subsequent annual updates.
Following the Mineral Resources Map is a spreadsheet that contains information on each Mineral
Resource Site parcel.
The Designated Mineral Resources Sites on the Mineral Resources Map satisfy King County's
responsibility to designate and conserve mineral resources consistent with requirements of the
GMA. All Designated Mineral Resources Sites have Mineral zoning. The criteria used in the 1994
King County Comprehensive Plan called for designation of properties that at the time were either
zoned outright for mining or those operating under an approved Unclassified Use Permit. In
addition to the designated Mineral Resources Sites, the Forest Production District (FPD) and
Forest (F) zone preserves the opportunity for mineral extraction. Mining is a permitted or
conditional use in the F zone. Because forestry does not preclude future mineral extraction, King
County considers the FPD as part of its strategy to conserve mineral resources.
The Mineral Resources Map also shows Potential Mineral Resource Sites. These are sites where
King County expects some future surface mining to occur or where the owner or operator
indicates an interest in future mining. Most of the Potential Mineral Resources Sites shown on the
map contain sand and/or gravel, however, a few contain other mineral resources such as quarry
rock and coal. Because of the geology of King County, most valuable metallic mineral resources
are located in the Forest Production District, and are therefore already protected from urban
development. Identification of Potential Mineral Resources Sites satisfies the GMA requirements
to not knowingly preclude opportunities for future mining and to inform nearby property owners of
the potential for future mining use of these areas in order to prevent or minimize conflicts.
The Mineral Resources Map also shows Non-Conforming Mineral Resources Sites. These are
sites on which some mining operations predated King County zoning regulations without
appropriate zoning or other land use approval. Mining for these sites has not been authorized
through a Land Use Map or zoning designation. These sites are shown for informational
purposes only. Mining can occur on an identified site only if mining has been approved as a
nonconforming use by the Department of Development and Environmental Services, and mining
activities have received all other necessary permit approvals. Because the sites have not
undergone formal review to be designated on the Land Use Map or zoned for mining, the sites do
not have long-term commercial significance. However, they can continue to serve mineral supply
needs.
The Mineral Resources Map also shows Owner Identified Potential Coal Mining Sites that contain
subsurface coal resources. These sites could be mined by either underground or surface mining
techniques. Because of uncertainties involving the economics of energy and related market
conditions, it is not always possible to determine the timing or likelihood of coal resources
extraction in potential coal mining areas. Underground and surface coal mining is subject to
permitting and enforcement by the Federal Government. King County regulates land use
decisions governing surface facilities. Because of the difficulty in precisely locating these facilities
prior to an actual proposal, King County determined to not apply Potential M zoning to owner-
identified coal resources sites.
3-37 September 2004
R-555
R-556
King County shall identify existing and potential mining sites on the Mineral
Resources Map in order to conserve mineral resources, promote
compatibility with nearby land uses, protect environmental quality, maintain
and enhance mineral resource industries and serve to notify property owners
of the potential for mining activities. The county shall identify:
a. Sites with existing Mineral zoning as Designated Mineral Resource Sites;
b. Sites where the landowner or operator has indicated an interest in
mining, sites that as of the date of adoption of the 1994 Comprehensive
Plan had potential Quarrying/Mining zoning, or sites that the County
determines might support future mining as Potential Mineral Resource
Sites;
c. Sites where mining operations predate zoning regulations but without
zoning or other land use approvals as Non-Conforming Mineral Resource
Sites.; and
d. Owner-Identified Potential Sub-Surface Coal Sites.
King County shall designate as mining on the Comprehensive Plan Land Use
Map those sites that had Potential Mineral (M) zoning prior to the date of
adoption of the 1994 Comprehensive Plan and those sites that had Mineral
zoning as of the date of the adoption of the King County Comprehensive Plan
2000 Update.
A mining designation on the Land Use Map shall not create a presumption
that Mineral zoning will be approved for sites with Potential Mineral zoning.
Potential Mineral zoning shall not be applied to additional sites.
Mining is an intense operation that may continue for many years. Mining operations can
significantly change the land being mined and have impacts on the environment and on nearby
properties. King County requires comprehensive review, including environmental analysis, prior to
approving a Land Use Map and zoning change. Site specific environmental review will also be
required for a grading permit or any other permit that is necessary for a mining operation.
Therefore, a comprehensive site-specific study is required prior to any such approval.
R-557 King County may designate additional sites on the Comprehensive Plan Land
Use Map as Mining only following a site-specific rezone to Mineral zoning.
Upon approval of a rezone to Mineral zoning, the Comprehensive Plan Land
Use Map shall be amended to designate the site as mining during the next
comprehensive plan amendment cycle. King County should approve
applications for site-specific rezones to Mineral zoning and applications for
permits that would authorize mineral extraction and processing only
following site-specific environmental study, early and continuous public
notice and comment opportunities, when:
a. The proposed site contains rock, sand, gravel, coal, oil, gas or other
mineral resources;
b. The proposed site is large enough to confine or mitigate all operational
impacts;
c. The proposal will allow operation with limited conflicts with adjacent land
uses when mitigating measures are applied;
d. The proposal has been evaluated under the State Environmental Policy
Act so that the county may approve, condition or deny applications
consistent with the county's substantive SEPA authority, and in order to
mitigate significant adverse environmental impacts.
September 2004 3-38
-
•
e. Roads or rail facilities serving or proposed to serve the site can safely
and adequately handle transport of products and are in close proximity to
the site.
If King County denies an application for a site-specific rezone it should remove the mining land
use designation and the associated Potential Mineral zoning for the site. If the county denies a
permit that would authorize mineral extraction and/or processing on a Designated Mineral
Resources Site, the county should consider new information generated during the permit review
process to determine whether the site is not properly designated as mineral resource land of long-
term commercial significance, the designation for the site on the Mineral Resources Map should
be changed from Designated Mineral Resources Site to Potential surface Mineral Resource Site.
In addition, the mining land use designation and the Mineral zoning classification for the site
should be amended to be compatible with the surrounding properties.
R-558
R-559
R-560
R-561
R-562
King County should remove the Mining land use designation on the
Comprehensive Plan Land Use Map and associated Potential Mineral zone or
Mineral zoning for any sites that have been denied a rezone to Mineral.
If a grading or other permit necessary for the extraction of mineral resources
is denied on a Designated Mineral Resource Site, the county shall evaluate
whether such mineral resource designation is appropriate. The re-evaluation
process may occur during the annual comprehensive plan amendment cycle
and information produced during the permit review process shall be used to
evaluate the appropriateness of changing the existing designation. If the
county determines that the site should not be designated as mineral resource
land of long-term commercial significance as defined in the Growth
Management Act, the site shall be redesignated to a Potential Surface Mineral
Resource Site on the Mineral Resources Map and to a land use designation
and zoning classification compatible with the surrounding properties.
King County may update the Mineral Resources Map to identify additional
Potential Mineral Resource Sites only during the four-year comprehensive
plan amendment cycle.
The preferred adjacent land uses to sites designated as Mining on the Land
Use Map are mining, industrial, open space or forestry uses. Sites for newly
proposed Mineral zones shall not be adjacent to or within Agricultural
Production Districts. Agricultural lands and operations should be protected
from significant impacts associated with nearby mine operations.
Mining activities are permitted within the Forest Production District,
consistent with Policy R-519. However, a conditional use permit shall be
required for mining activities in the Forest Production District located within
one-quarter mile of established residences or for proposals seeking to use
local access streets where abutting lots are developed for residential use.
In order to comprehensively assess the environmental impacts associated
with a zoning change, conditional use or operating approval for a mining
proposal, the range of environmental impacts, including short-term and long-
term effects arising or existing over the lifetime of the proposal, shall be
assessed at the earliest possible stage. This should include the potential for
future proposals for structures and operations related to mining, such as
asphalt and concrete batch plants.
3.39 September 2004
R-563 King County should prevent or minimize conflicts with mining when planning
land uses adjacent to Designated and Potential Mineral Resource Sites.
Subarea plans may indicate areas where mining is an inappropriate land use.
Designated and Potential Mineral Resource Sites and nonconforming sites
should be shown on Mineral Resources Map and subarea plan maps in order
to notify nearby property owners and residents of existing and prospective
mining activities.
R-564 The periodic review process for mineral extractive and processing operations
shall include sufficient public notice and comment opportunities. The
purpose of the periodic review process is to provide opportunities for public
review and comment on the mineral resource facility's fulfillment of state and
county regulations and implementation of industry-standard best
management practices, and for King County to modify, add or remove
conditions to address new circumstances and/or unanticipated project-
generated impacts. The periodic review process is not intended.to re-
examine the appropriateness of the mineral resource use, or to consider
expansion of operations beyond the scope of existing permitted operations
since that review would be accomplished through the county's permitting
process. The periodic review is intended to be a part of King County's
ongoing enforcement and inspections of mineral resource sites, and not to
be a part of the county's permitting process.
R-565 Conditions and mitigations for significant adverse environmental impacts
associated with mining operations and their associated structures or
facilities should be required, especially in the following areas:
a. Air quality;
b. Environmentally sensitive and critical areas, such as surface and
groundwater quality and quantity, wetlands, fisheries and wildlife
habitats, and aquatic.habitats;
c. Noise levels;
d. Vibration;
e. Light and glare;
f. Vehicular access and safety;
g. Land and shoreline uses;
h. Traffic impacts;
i. Visual impacts;
j. Cultural and historic features and resources;
k. Site security; and
I. Others unique to specific sites and proposals
R-566 King County should work with the state and federal governments to ensure
that proposals for underground mining, oil and gas extraction, and surface
coal mining are reviewed with consideration of local land use and
environmental requirements.
R-567 King County should work with the State Department of Natural Resources to
ensure that mining areas are reclaimed in a timely and appropriate manner.
Reclamation of mining sites in the Forest Production District should return
the land to forestry. Where mining is completed in phases, reclamation also
should be completed in phases as the resource is depleted. When
reclamation of mining sites located outside of the Forest Production District
is completed, the site should be considered for regesignation to a land use
September 2004 3-40
R-568
designation and zoning classification compatible with the surrounding
properties.
King County shall encourage the removal of existing stockpiles of previously
mined material in order to promote and achieve reclamation of land to its
highest and best use.
3-41 September 2004
,------..-. ~ V: \ -~-. ;rJP ~K" :.
\ ~ ? .. , ..... , '
\ _:.::~~
J ',>-; .
i
i Ii
I
{
j
i
i
\
I
i
\
)
j
I
I
\
\
I ;
,/'/ ....:,<:-;;,,~
/if'
I ..,,
j
// ~)
I -· I;
/ l :-,--•.•
I I .. L .. I i I v'.
I "
j
\
·tJt
.,.
·(·
/
/ t, (. __ ,;# .... I
i
\
.....
(. ··. _:. __ _
\ ((
·,., //,, . ________ ,.,.~
.-''·
Ki ng Co unty Com prehe nsive Plan, 2004
Chap ler Th ree, Rural Legacy and Natural Resource Land s
mltcny'fHOJOOs\corrplan\2004'2004 ag lc rest mxd
AWC ~liddes707\g cs•mVT.aps\200.:. 12\2004_KCCP\aW¥C_20041222_a;i !crest pd!
The inlorrN.l :o n r,c:luded on lh1s m.i.p h as t:een co~led by
King County slatt from a va.rlefy ol sources and 1s aubJeet 10 chango
.,...11\oul notice Kin9 COJnty ma)(es no reprue nl ations or
warrarHios, express or 1rfliied H to accur.xy, con,>leter.eu,
~meliness. or nghts to the wi1t 01 such inform.aliof'i. Kmg Co1.:n ty
shall not be liable lor any 9M1tra!. spodal, indireci, incidental, or
COOS6quenti al d;lmages ind udin9, b ... 1 not ~rT'Vled lo, lost
revt1 nues or lost profi"..s resulting t,om the use o r misuse ot tho
flfo rrnajon con:ained on !his map. Any sa;e ol th~ map o,
l'lforrnanon on rhis m.ip is p<onibiled excep1 by wrinM permission of
K!llgCounty
The maps Jn the King County Comprehensive PJan and its lechn>cal appendices a re produced with a COITf)u ter geographic
information system. They are redlJced in Size but avaf/able at a Jarger scale.
:....-....,.r~---\
Agricultural and
Forest Lands 2004
~::t!IJ Fores t Producti on District
-U.S. Fores t Service Land s
I Agri cultural Prod ucti on Distri ct
In corpo rated Areas
i ___ .. J Tribal Lands
""'-Urban Growth A rea Boundary ,, _ · Alpine Lakes Wildern ess Boundary
~ Rural Fores t Focus Areas
® Bear Creek
® West Wall Snoq ualmie
© Lake Joy
@ East Wall Snoq ualmi e
® Mitche ll Hill / Raging Ri ver
® South Fork Snoqualmie
© Issaq uah Creek
® Cedar River/ Ravensda le
CD West Black Diamo nd
® G reen Ri ver
U.S. Forest Ser,te, Ki ng County Departments of Assessments , Natu ral Resources and Par'<s ,
and Development and Environmenta l Services
(® King County
N + 0 2.5 10 -,.., ..
nt"'tnho l"' ?nn.a.
'/ .. -"':"' <::,:;
/'
,·-·-·--. ,,, . ,-~')\ ' .
\ -Sn~~.:-.ix ~ ~ \ 'a1IIIJ f -·::-·-· · ... -·-·-·-:-·--·-·-:-_ ·-·-·-·--·-·-·--·-·-·--·-·-·--·-·-·----·-·-·--·-·:... . ----~--·..:.: ___ ...Ji!'~~,y7 ----~----·-·-·-·-·--·---·-·--·-·--,
/ D , '·"'\ ~ , \
/ ... ~ \ ~~ f 'l.,
I ~~A I I >. .ll"-'-~3':!i· . (--......,
/ . "-:,,..,,'7: ' ./ r ; ' )
I .,.· -:\. -, I
I
...... ~_-"'.' 1: __ {' ' (' \ ""'J,!lle . ' !,4' . ' { ' i ',, ··, ~~ ..... ,
I ·".; , /.1 . ~-,. t-i -, \. • • / <I" i ) '\_,.) I ' 4 -;t,
'\ • I / ~ . \ ,' ';;. . , \
I
:;'c ' i J-~
\ . ~' !
' / 1 \ I ., . t,
i )
' l i \ . J \ /"..,..~.--..... 1
\ ' I ! ' •j _,
I I ~.,F ... / ) ' .----------...1
... ~·G>"' . (
/~ (
(
. -.. ,· -.. ,...i
(• .,.. . -., )
/ I -";. (-~-· -'I • ._,, / r . ., :·' ---~-___ }
I ~ ...:7 ! • ~ ... t ,( / : r ,... '. I
/ J .,\ -! ;-I
I ,. , . ./ / -· I .. ·--. ® ,..--/' f r-~;;-~_·· ,. Jf _/ '\. .,.> ,..-.,
I f..' ~-~\ .--· ~ , ,r· .. /
I I\ "" ~ .,, ' ~ ·: / /--'
) ~·-""·; ' / · ~-1 ; f
~-' ., ) -. .-· ·~~ ~~ ~-Parlr (
/) ·' ,. , -" -.. ; -""' r I ,, ,, ~ . . . _,../ ~ , //31,... ..
\ ' . -. '· . ' •' ' ___ ,..,._ ( ' ...
) , re...)-iw:.'? -. :_ ,,., .. '""------~/ <) ~ Equestrian Communities 2004
I • · ~ ' ./' ·--~-_,...-I
i ~· ,-~ i ·; -~ ~ . .... \
l ~ ~
\ \.... i \ /'''--. ' ..... -····· ·,~ ..
............. ______ ,,. ~'· -·,, --_, ... .,,?,$:"<~
. ~~, ~~
"\;" ·. ederal_l'lay I J
. ~-~ / .. ,.,_ ·, ,, I
. ' ., '\.. \ )", -. . "'-.-, ....... -· ....... -.J l.. "·,
i
'
}
-\ ,...
'"
\) -------
r./,..>
( t".("_~~-.,,. v .. /\..._:.._'-"·-
-,
"'-.---..
·, . .-.......
King Counly Comprehensive Plan, 2004
Chapler Three, Rural Legac y and Natu ral Resource Lands
tn.:\lony""o,ects'.cOfll>an\2004"'2004_•qu11slra&n ffl.ld
AWC \\ddes707\vm-m'.mapa\2004i 12'\20CM _KCCPlawe_2004122:> tq1J9Slri.ln p,:f
Th• "!crrna:1on ind~ on 1h ~ map has b-n con,,iled by
Kin; County staff 'rem a ¥A/MIity ot soorC•s aw.t •• aut>,ect 10 c h~
w«hout nollc• King County 11\iu.•s no represer l.VIOnS Qt
w:wr,m1M ewpre$s Of ifT1:lied. as to &oc 1Jrac y, cor""Ole1tnHS.
limo~nus Of rjghts to tt,• use ol sucl'I lnf0t mat on Ku,g Coumy
shall no t be liable l i>r any Qo!!neral , spec ia l indl reci. incrdo ntal, or
consequential darN19 &1 h:kJding , b>J1 n ot limited 10 lost
rn•l"UH 0t lost profit, re,v l ing l!om tt'le ut.e Of mis1.1 se ol the
r ton-i.atiol'\ cont.1int4 on l'u ~ My sale ol th• map o,
.,IOffl'\I.IC)n on this rNP • prMl:ute d exc~ by ·Nrir..e!\p&rmssiOl'I of
.,. .... ··1._._ "· \
{
\ ;
J
\
~ \ , I ' 'I . ..... , \ ,.. . .,,.--'~ ......... __ .,.. .... )
.l ', ""°c''"' ·-. ( ~ -'-/'
The maps In the l(;ng County Ccmprchens/ve Plan ana Hs lcchniCal appendices a re produced ..;111 a compurer gcographic
information system. Tney are reduced In s/Le but available at a 1a1gc1 scale.
" I ' . ~ \ '", z../\. '-_____ ,......__ __ _
;·--·-.
L .... -.. .J
Equestrian Commun ities
Incorporated A reas
Tribal Lands
"'-Urban Growth A rea Boundary
Source: Kmg County Departmcnl of Devel qimenl and Environmen lal Servic es
(® King Cou nty
2.6 ~ 10 -,.... ..
N +
--6-L--..-...-.n A
•
,·--·-----\ -·
I
\
/
I
i
;'
I
i
i
i
\
I
i
!
I
\
\
/
i
\
\
I
./ I .,. • .;.r:;~
/+-"~
I
' /
//
i
(
I
i
j
.·'
/
i
I
\
\
//
i
\
9t
/
I
/
' ·,. ________ ,,,..,.
4
,,
f-
3
)
,, \
-
King County Comprehensive Plan, 2004
Cha pte r Three, Rural Legacy and Natural Resource Lands
m'fony'4W.,,..;tt'U,ff,f,l1m'200-'l200<!_nr.111l11Ud
~1/</C '11ddo6al'O]\g,•·m -p,,.'2()0,i1?\2[)D<I_K('..CP.a,wi::_?Ol'.Wt7" _,n.-..,,..r p,:I!
. 'L '1 ' . ---------~----------------=-=~~ .~;~~--~---£.¥'-l ----------------,1='..\ . ~--·--·-,-. .i~,;,. ' __t . -••-,,________ . i-"',, I ·------..--. ' . ' •, ' ··, \
. ' / .,Y , .. , ··•·., I ~, ~ ('.._ ,.ff . C.. , :·,.. c~----.. J c--'--4l! . { ,-, ·-· ,., '·. --· r:-/ . 51 . , ·····--·-----, _, ;, 9:l ____ ,., _____ , i _,,
. ·'·". ,· . '· ' . 1"' , .• ,, ,· ! . '
·~-i •. ' 'CJ ( _7;.~·-:~ ---_,c·· ,' ' (\
; ' \ ,J' ,.• ... , ,, , .,., -,., C· f ,.. )
// . . ' ,-.;c....i.t··. . ~
= , ~--., ' i ,~-.
t
l..l
___ :'v
r--:--·
..J
__ c:-;--
r··--: /~~
I ,--·--~ . ' \ I
3:-··-·1
I •
-'-··-' ,·' .-·
_.J __ ,..,.--
i., _____ !i---··------·r··--·-··-···· ---~·-·:
l / j -. ./ . . / . r1"\-----~.r~
:_-., ,f j _J r-'--, --:··L -:-Lr5 l i
.. .,-·· I
>_)
77
-i
( ___ _
:,.. ....... _,.i
1:
\
·-·1.
'·-·-,
\
-·1 __ ·~
'-.-..... ...__.,
l
-·~ \.,
'i 21~9 ,:... ___ ,_ ~·;
.i~,9 2 , , i Lc___r '-•-\ , 9 ··72 ,-, 1.C. • '· "-. I
-··r , ··, '·, --. ,
1
1 . a§P --"' ? ' . J --, -" ·u ,,,.u q "\"---s / \... / -\__ ,~ I ~ •~ . >· . u '-'1 I ) 81 .-c, , ; ·-4li ( ----.. ---.,_ -~~i..t·-~.i \64
, ___ ;.....,,.. l ..... ---) __ .,: !'""-
· 96 , · : · ! &a-· •---: 1 0 _)
r·-·
/ __ /
//
'\, ) I',,-
I
f ,../
., ' -,~
.---------~-,! . (
I r{
/./
·-·-' /
<(
I
Mineral Resources 2004
32
, ')
109
f;;,.
Designated Mineral Resource Sites·
Potent ial Surface Mineral
Resource Sit es··
No n-Confo rming Mineral
Resource Sites· ..
Own er-Identified Potential
Sub-Surface Coal Sites"'·
Incorporated Areas
C.-~-:-.J Tribal Lands
~ Urba n Growth Area Boundary
''-··' Forest Production District Lin e
"Sites v.1!/J Mineral Zoning.
-·, ,•~} I
·!:.., 5 4 /
_,; I , ••. , 1 os r s6 s:;_ ,.,._ ~ . . ~ \
) ; -: • . '·, ., --·, 1 ···,
>l. ·---. • ·-· ·-. , --. ~~ 62 -'·---·, ···----·,
-~~-"--_,.......~, ~'>.. • ..._:,~_
"Sites identified by the landowner or operator prior to Nov. 18, 1994 and sites that as of Nov. 18, 1994 had
peooing rezone applications for Ouarrying,-Min,ng (now Mineral) zoning or had potential Quarrying/Mining
(now Mineral) zoning.
"'Sites on which mining operah·ons pre -date King County zoning regulations, but without zoning or other
land use approvals .
The 1nfo1mallon lnc..,ded on ttus rnap has been comp~ed by
l(lr1g C<>unty ~"" h orn a 1111rsety or -1ovron a /"!d Is s..iijecl b cha~
'Mtnout nclk:,e,. King C¢IJl'lty mal(u fie) reo,esent&tioos ot
Wt111M1i.t1S. u.press Of m pied. as to acc;urllC)', complalann&
lim•111ess. or rJ9hls kl the use ot suet, lr1lormabon. KJng County ...-.,1 I\OI be bt:.e !o, a.ny gene ral. $J)(ICk1J. lr.clirect. lf\Cidwita l Of
001",1.fWlw.ntia.l dam.aQiM-lr"<:lvdil"IQ. bot not *'11Ted to. lost
re111nuu oi lost p,om, re ,u!tng lrorn the 111• 0< rr.11uu ol lhit
,nlorrr-.;,T,Of'I oonlJlnOO on 1tis map My !,,)Je ot 1tu map Of
tntQ.rmal1('11'1 ('11'1 ttws rri\p is p'Ohlbit&d e•c:ep1 by ...,,tuen perrnissjoo o t
l(..,n r....,.,,,,.
·,, .
l_-...._,~----___.,,,-.J '.
c"
·-:c '.;E .. ' ~ \~
--. ,,, s 1 r · ~ \.,.---., .. -.. -.,· .. ,_ ·
\,___ ~8 9_$5 "l~~' ,-" ·----~
. ' "\..,;, ,e-,-._ .• c, ~ "-""~-~ \,
I ~ . , J -<••• ' '-;,· ·, . -I
.J .. '-',
The maps 1n the King County Canpr11hensN11 P1an and;$ f~nlcaJ Jt.~,ce-s arc p,<>duccd w,:h ii' compv1c, {l(l()Qraphic
in.'ormtt~n sy51.tJm. Thcy are rtlduc~;, siM bur dvdil.lble at .:i l11rpc, scaie.
' _,-... ___ _;; .....__ __ .
•••• Owner-Identified Potenb'al Sut>-Surface Coal Sites are not parcel specific.
Source: U S. Forest Service. King County Depanments of Assessments and Developm ent and
Environmental Services
® King County
N + ae IQ
"'' ..
October 2004
• I • I 4 I ' .. __ ..... ______ :__ _______ ---..I,-
DESIGNATED MINERAL RESOURCE SITES DESIGNATED MINERAL RESOURCE SITES
Map# Section-Site Name and/or Owner/Operator Product* Total Site Map# Section-Site Name and/or Owner/Operator Product* Total Site Township-Acreage Township-Acreage
Range (approx.) Range (approx.)
1 25-21-06 Cadman S & G/Flintston S&G SG 75 18 28-26-11 Meridian Aggregates R 38 2 11-20-07 Plum Creek Timber Company SG 476 19 11-21-06 John Henry Coal Mine/Palmer Coking C 375 21-20-07 12-21-06 Coal
3 21-22-03 Ideal Cement Co/King County SG 39 20 01-21-06 Reserve Silica CorporationPlum Creek s 612
36-22-06 Timber Co. and Silica Sand Mine
4 28-22-03 Maury lsland/Lonestar Northwest SG 250 21 01-19-07 Weyerhaeuser Co. s 625
5 27-22-07 Kangley PitlMeridian Aggregates Co. SG 608 22 34-22-07 Elk Pit/Mutua! Materials, Inc. CL 60 (398 acres) and Stoneway Concrete
Gravel Pit/Gary Merlino Construction
6 28-23-06 Cedar Grove Pit/Queen City Farms SG 315 23 32-24-06 State of Washington CL 21
7 33-23-06 Lake Francis PiUPlumb Creek Timber SG 143 24 31-24-06 Section 31 piUKing Co. Sh/Cl 322 Co.
8 33-23-06 Cedar Grove Pit/ANMARCO SG 35 25 32-24-06 Interpace Harris Mine/ R.Thompson and SG 60
Eltra Corp.
9 20-23-06 Cedar Mountain Pit/ Rivera & Green SG 57 26 35-22-06 Meridian Minerals Co. SG 57
't' 10 19-22-06 Black River Quarry SG 374 27 29-23-06 Pinnacle Exploration SG 49 .,,. 20-22-06 "' 29-22-06
30-22-06
11 22-24-06 Gravel Pit/Washington Aspha!t Co. and SG 320 28 29-23-06 ANMARCO and G. Newell SG 115 27-24-06 Glacier Ridge PS 32-23-06
12 08-26-07 J. Margan SG 13
17-26-07
29 29-23-06 Plum Creek Timber Co. SG 200
13 19-24-08 Snoqualmie/Weyerhaeuser Co. and S. SG 665 30 27-24-06 Issaquah/King Co. SG 18 20-24-08 Parsons et. al.
14 05-23-06 Sunset Quarry/Meridian Agrregates RS 120 31 05-23-06 King County SG 383 15 06-23-06 Squak Mountain Quarry/M. Palmer RS 16 32 33-23-06 Lake Francis Plum Creek Timber Co. SG 233 16 22-24-07 Raging River/Cadman RS 46 33 35-22-05 162nd Av SE/James Development Co. SG 28
and 0. Joscelyne
17 33-20-07 Highway 410 Quarry/J. Laramie RS 34 34 35-22-05 Washington Asphalt Co. SG 23
Cf) ro
,?.
ro
3
O"
~
"' 0
0 ,.
Mineral Resources Property Information for the Mineral Resources Map
POTENTIAL SURFACE MINERAL RESOURCE SITES POTENTIAL SURFACE MINERAL RESOURCE SITES
Map# Section-Site Name and/or Owner/Operator Product Total Site Map# Section-Site Name and/or Owner/Operator Product Total Site
(/) Township-Acreage Township-Acreage ro Range (approx.) Range (approx.) )<
ro
3
O" 35 35-22-05 T. Scarsella ~ 11 56 10-20-07 Weyerhaueser Co. 80
"' 0 36 07-25-06 Cadman/King Co. 24 57 15-26-07 State of Washington 320
0 37 33-23-06 Merlino Property/ANMARCO 32 58 16-21-05 State of Washington 38 "" 59 17-23-07 State of Washington 640
18-23-07
19-23-07
20-23-07
39 20-23-06 Rivera and Green 21 60 26-21-06 M & K Company 18
40 22-26-06 T. Alberg 40 61 27-24-06 State of Washington 40
41 31-26-07 T. Alberg 160 62 30-20-08 Weyerhaeuser Co. 141
36-26-06
42 8-26-07 R. and A. Thompson 11 63 30-21-07 State of Washington and Palmer Coking 60
17-26-07 Coal
43 32-23-09 R. and A. Thompson 145 64 30-21-08 State of Washington 168
44 11-21-05 B & M Investments 174 65 34-24-06 State of Washington 32
45 25-22-02 Doane Family Ltd. 60 66 35-24-06 State of Washington 20
w 46 08-25-06 W. Nelson 86 67 36-20-06 State of Washington 79
"' 47 18-21-07 Palmer Coking Coal 79 68 36-20-06 State of Washington 40 0
48 30-21-07 Palmer Coking Coal 275 69 36-21-06 State of Washington 152
50 36-21-06 Palmer Coking Coal 116 70 36-21-07 State of Washington 640
51 06-23-06 Palmers 39 71 36-23-06 State of Washington 115
52 12-23-05 R. and R. Schroeder and Pacific 30 72 04-21-07 Weyerhaeuser Co. 173
Company Constructors
53 02-20-06 State of Washington 36 73 03-25-09 Weyerhaeuser Co. 3079
04-25-09
05-25-09
10-25-09
33-25-09
34-26-09
54 03-91-33 Weyerhaeuser Co. 36
55 02-20-07 Weyerhaueser Co., State of 634
12-20-07 Washington, Metro
I • •
! I (. , 4 .:, I ,_ -I _c •--•-•---'--I__!, _ _. __ (._[. __ ,..
-
POTENTIAL SURFACE MINERAL RESOURCE SITES POTENTIAL SURFACE MINERAL RESOURCE SITES
Map# Section-Site Name and/or Owner/Operator Product Total Site Map# Section-Site Name and/or Owner/Operator Product Total Site
Township-Acreage Township-Acreage
Range (approx.) Range (approx.)
74 11-4-07 Weyerhaeuser Co. 3655 84 28-20-07 Weyerhaeuser Co. 669
22-4-07 32-20-07
32-4-07 33-20-07
26-25-07
27-25-07
34-25-07
35-25-07
75 01-19-07 Weyerhaeuser Co., United States, U.S. 4214 85 04-19-07 Weyerhaeuser Co. 1572
(4-8)-19-8 Corps of Engineers 05-19-07
12-19-07 32-20-07
28-20-08
31-20-08
32-20-08
33-20-08
36-20-07
Cf 76 {17-20) of Weyerhaeuser Real Estate Co. 1765 86 34-25-07 L.A. Welcome 24
'" 23-09 and
(28-30) of
23-09
77 21-23-09 Weyerhaeuser Co.and State of 705 87 36-21-05 Sparling/King Co. 41
27-23-09 Washington
28-23-09
78 13-24-07; Weyerhaeuser Co., Riley, Everett, 1926 88 21-24-07 Raging River/King Co. 40
(17-20) of Hamerly
24-07
79 06-21-07 E. Seliger, Weyerhaeuser Co, 1167 89 32-22-07 Lake Retreat/King Co. 82
7-21-07 Bremmeyer, and Palmer Coking Coal
80 08-21-07 Weyerhaeuser Co. 113 90 35-22-02 Sprowls/King Co. 40
81 16-21-07 Metro 599
82 24-21-06 Cadman Black Diamond/Weyerhaeuser 434 92 23-26-07 Swan Quarry/King Co. 76
u, Co.
© 83 20-20-07 Weyerhaeuser Co. 925 93 31-23-07 Route 18 Fill Project/P!umb Creek SG 40 "O
iii 29-20-07 Timber Co. 3
0-
~
"' 0 LEGAL NON-CONFORMING MINERAL RESOURCE SITES 0 ...
(/)
"' ,.
"' 3
[
"' 0
0
+'
"' 6,
"'
Mineral Resources Property Information for the Mineral Resources Map
AND EXISTING MINERAL RESOURCE SITES IN THE FPD
Map # Section-Site Name and/or Owner/Operator
Township·
Range
94 06-19-07 R. & B. Jensen
95 29-20-07 Moulder Pit/Weyerhaeuser Co.
96 30-21-07 R. Morris and Palmer Coking Coal
97 15-22-06 Maple Valley/R&H Partnership
98 07-23-06 PG and RT Schroeder
99 23-26-06 Chapman Pit/Alberg
100 34-25-07 L.A. Welcome
101 29-23-09 PG and RT Schroeder
102 26-22-05 Calhoun/King Co.
103 34-22-06 Summit/King Co.
104 13-20-06 Enumclaw Quarry/Richard Pierotti
105 06-20-07 Veasey/Dwight and Doris Garrett
106 27-26-11 Miller River QuarryMRGC Timberland
107 37-79-20 Black River Quarry/Lloyal Newburn
108 37-79-20 Black River/MaryEllen Hughes
109 34-22-07 Elk Pit/Mutual Materials Co.
110 31-21-07 Palmer Coking Coal Co.
111 16-24-07 Hoover/King Co.
112 04-25-07 Redmond Pit/Cadman Gravel Co.
Product Total Site
Acreage
(approx.)
SG 13
SG 60
SG 158
SG 6
SG 22
SG 53
SG 5
SG 53
SG 23
SG 176
RS 14
RS 8
R 11
R 5
R 9
Cl 60
20
40
SG 18
• •
SG = Sand & Gravel
RS = Rock & Stone
R = Rock
C = Coal
*KEY
ShCI = Shale & Clay
Cl = Clay
S = Silica
NOTE: Each map number corresponds to one or more parcel
number(s), and in some cases different owners and operators.
The acreage listed represents the sum acreage of all the parcels
of the site. Please refer to the technical appendix for the parcel-
specific version of this table.
• •
Cha ter Four
Environment
•
Chapter Four
Environment
With chinook salmon and bull trout now listed as a threatened species, and other valued species
dangerously close to joining the list, protecting both our rural and urban environments remains a
critical concern.
King County's regulations for protecting the environment are some of the most stringent in the
country. In a region as rainy as the Pacific Northwest, maintaining healthy wetland systems,
controlling stormwater runoff and preventing development on sloping hillsides are all vital in
preventing erosion and flooding. Without proper regulatory control, damage to private property,
as well as salmon streams, is unavoidable and costly.
4-1 September 2004
I. Na1ara:I Enuironment
A. Protection and Regulation
Protecting and restoring air quality, water resources, soils, and plant, fish and animal habitats are
among King County's primary goals. This chapter establishes policies to protect the environment
and enhance the region's high quality of life. Most of this chapter's policies provide a basis for
either new non regulatory approaches or for existing regulations. Some new regulations are
necessary to implement the policies. However, new regulations such as wetland mitigation
banking offer flexibility compared with existing regulations.
Every resident of King County has an equal right to a healthy and safe environment. This requires
that our air, water, earth and food be of a sufficiently high standard that individuals and
communities can live healthy, fulfilling and dignified lives. The duty to enhance, protect and
preserve King County's environment rests on the shoulders of government, residents, resident
groups and businesses alike.
The Growth Management Act (GMA) requires that critical areas be designated and protected.
Critical areas include wetlands, areas with a critical recharging effect on aquifers used for potable
water, fish and wildlife habitat conservation areas, frequently flooded areas and geologically
hazardous areas. This chapter establishes policies for designating and protecting critical areas.
King County Code Title 21 A provides the regulatory framework for these policies.
One of the most significant environmental issues facing King County is the recent listing· of
salmon id species under the Endangered Species Act. Wild Pacific salmon have great cultural,
economic, recreational and symbolic importance to the Puget Sound region. It is King County's
goal to ensure long-term protection of our salmon resources to harvestable levels for today and
tomorrow, with the least economic impact possible. Successful restoration and maintenance of
healthy salmon populations will require time, money and effort, and collaboration with federal,
state, tribal and local governments, as well as businesses, environmental groups, and citizens.
To meet this goal, King County and the region will need to consider salmon when making
decisions about land use and development, providing facilities and services, maintaining roads,
parks, and flood control facilities, and building new capital improvement projects.
Relative to land use, three types of environmental situations exist in King County. In highly
developed urban areas, the quality and functions of most critical areas have been significantly
affected by past development. Additional impacts in these affected areas will likely result from
higher density development, but these impacts may be preferable than similar impacts to currently
pristine areas, which can result in a net loss of the region's natural resources. Salmon-bearing
streams and rivers do pass through many urbanized areas in King County. The challenge of this
plan is to balance the need to meet urban density goals and prevent urban sprawl, while also
ensuring such development occurs in accordance with the provisions and requirements of the
GMA and the Endangered Species Act. To meet this challenge, a variety of regulatory and
nonregulatory tools and programs will be needed.
In other urban areas with low levels of development, significant critical areas are usually more
intact than in highly developed urban areas. Onsite mitigation of new development, if designed
well and monitored, may achieve resource protection. Achieving development goals must be
balanced with protecting critical area functions and tailoring individual solutions by following the
guidance of comprehensive plan policies that recognize both critical area protection and the need
to reduce urban sprawl.
September 2004 4-2
The Rural Area and Natural Resource Lands contain the bulk of King County's remaining wildlife
and fisheries values. Protection of resources through land use planning and impact mitigation will
be most successful in these areas, and it can occur with the least disruption to intended land
uses.
While critical areas within the Urban Growth Area will receive adequate protection, the emphasis
is to protect and enhance critical areas in the Rural Area and Natural Resource Lands and to
avoid impacts to specific animal species, such as salmon and bald eagles, that use or pass
through the Urban Growth Area. These policies provide for a watershed-based approach to
planning. This approach acknowledges that different areas of King County have different
resource values and face different levels of development pressure, therefore different methods of
protecting critical areas need to be developed to balance the protection of the environment with
the need to reduce urban sprawl and preserve our quality of life.
E-101
E-102
In addition to its regulatory authority, King County should use incentives to
protect and restore the natural environment whenever practicable. Incentives
should be monitored to determine their effectiveness.
King County should take a regional role in environmental stewardship
through direct education, coordinating of educational efforts and
establishing partnerships with other entities that share similar environmental
concerns or stewardship opportunities.
King County needs to coordinate many programs with other agencies. Coordination with the
Washington State Department of Ecology and affected jurisdictions is necessary to comply with
mandates of the Clean Water Act that address point and non-point source pollution. Further
coordination with air quality agencies, such as the Puget Sound Air Pollution Control Agency and
Puget Sound Regional Council, is needed to exchange information and develop consistent
programs. Coordination with water service providers who use groundwater sources is necessary
to protect the region's groundwater quantity and quality.
E-103
E-104
King County should coordinate with local jurisdictions, federal and state
agencies, federally recognized tribes, citizen interest groups, special
districts, and citizens to develop Water Resource Inventory Area plans for all
areas of King County.
Development of environmental regulations and restoration projects should
be coordinated with local jurisdictions, federal and state agencies, federally
recognized tribes, special interest groups and citizens when protecting and
restoring the natural environment consistent with Urban Growth Area, Rural
Area and Natural Resource Land goals.
King County will use existing and updated subarea and functional plans and Water Resource
Inventory Area plans to provide guidance to programs, regulations and incentives to protect and
restore environmental quality.
E-105 Environmental quality and important ecological functions shall be protected
and hazards to health and property shall be minimized through development
reviews and implementation of land use plans, Water Resource Inventory
Area plans, suliace water management plans and programs, flood hazard
reduction plans and park master plans. These plans shall also encourage
restoration of critical areas as defined in the Growth Management Act, and
include an adaptive management approach.
4.3 September 2004
E-106 King County wishes to create an equitable relationship with all citizens in the
Rural Area who own and/or control potential development or redevelopment
of property with critical and/or significant resource areas. However, some
affected property owners may not wish to enter into a rural stewardship, or
farm, or forestry stewardship plan and will choose to accept fixed regulations
under the critical areas, clearing and grading, and stormwater ordinances.
These property owners are entitled to have their property assessed at the
true and fair value of real property for taxation purposes. The portion(s) of a
property that are not developed or redeveloped due to environmental
constraints shall be assessed to reflect the presence of physical and
environmental constraints as provided in RCW 84.40.030 and K.C.C. 4.62.010,
4.62.020, and 4.62.030.
E-107 The protection of lands where development would pose hazards to health,
property, important ecological functions or environmental quality shall be
achieved through acquisition, enhancement, incentive programs and
appropriate regulations. The following natural landscape features are
particularly susceptible and should be protected:
a. Floodways of 100-year floodplains;
b. Slopes with a grade of 40 percent or more or landslide hazards that
cannot be mitigated;
c. Wetlands and their protective buffers;
d. Aquatic areas, including streams, lakes, saltwater shorelines and their
protective buffers;
e. Channel migration hazard areas;
f. Designated wildlife habitat networks;
g. Critical Aquifer Recharge Areas;
h. Marine beaches, wetlands, intertidal and subtidal habitat and riparian
zones including bluffs;
i. Regionally Significant Resource Areas and Locally Significant Resource
Areas; and
j. Fish and Wildlife Habitat Conservation Areas, and other critical habitat
areas identified for protection through Water Resource Inventory Area
plans.
E-108 Regulations to prevent unmitigated significant adverse impacts will be based
on the importance and sensitivity of the resource. The presence of a species
listed as endangered or threatened by the federal government may be
considered an unusual circumstance and the county may use its authority
under the State Environmental Policy Act (SEPA) to mitigate for significant
adverse environmental impacts to that habitat that supports those species.
E-109 King County should promote efficient provision of utilities and public
services by exempting minor activities from its critical areas regulations,
provided the agency has an approved best management practice plan
approved by King County, and the plan ensures that proposed projects that
may affect habitat of listed species be carried out in a manner which protects
the resource or mitigates adverse impacts.
September 2004 4-4
B. Air Quality
1. Overview
The preservation of clean air is essential to the quality of life enjoyed by residents of King County.
Since many of the long-term solutions to air pollution in our region now depend on land use and
transportation decisions, King County must assume a more active role in maintaining the region's
good air quality.
Clean, healthy air is a major contributor to the health of the public. The elderly, those suffering
from respiratory illness, and young children are especially prone to the harmful effects of air
pollutants. People with chronic respiratory problems, such as asthma, are most sensitive to
particular forms of air pollution, such as ozone and particulate pollution.
Puget Sound Clean Air Agency (PSCAA) has the lead regulatory and monitoring responsibilities
for the region in accordance with the Clean Air Act. PSCAA has a lead role in developing
strategies to reduce these emissions throughout the region. King County will continue to work
with PS CAA in implementing emissions reduction efforts. King County will monitor the
government's own emissions and will work to develop policies and projects to reduce them.
Further, as the land use authority for unincorporated King County and the governing body for
Metro Transit, King County will consider the air quality in its own policy and planning efforts.
The major improvements in air quality result from collaboration and partnerships among public
agencies, and between public agencies and private interests. Examples of partnerships include:
• Diesel Solutions partnership demonstrating the potential of ultra-low-sulfur diesel fuel;
• Creation and implementation of the new rules regarding control of vapors from gasoline
pumps at service stations, where collaboration between government and the private
sector facilitated the development and are working on the efficient implementation of the
rules' provisions;
• Three stakeholder processes with businesses, governments and nonprofit to form
consensus on implementation policies for ozone, particulates and greenhouse gases.
2. Ozone, Fine Particulate, Toxics
Ozone will continue to be a focus for King County. Though the region has attained the National
Ambient Air Quality Standards, the margin for failing and slipping back into a non attainment
status is tight. The ozone strategy identified by PSCAA for our region focuses on reducing volatile
organic compounds (VOCs). The PSCAA has stated that volatile organic compounds are the
main concern. Emission of volatile organic compounds results mostly from petroleum refining,
use, handling and combustion.
In addition to ozone, there is a serious health threat from fine particulates. Diesel emissions are
one of the county's largest sources of fine particulate emissions. King County's participation in
the ultra-low sulfur diesel (ULSD) program, known as "Diesel Solutions," has made tremendous
strides in cleaning up King County Metro's fine particulate emissions. Indoor burning and outdoor
burning are a major source of fine particulates.
Lastly, toxics are becoming an increasing concern for the region. Examples of air toxics include
benzene, formaldehyde, mercury, and dioxins and literally thousands of other air toxics. The air
quality impact of toxics are not be evaluated in isolation. Their greatest health risk comes from
their combined effect. National air toxics assessment data indicate that air toxics risks in the
Puget Sound region are in the top five percent in the nation. Local air monitoring data done by the
State Department of Ecology indicates that diesel exhaust and wood smoke are key contributors
to toxics. Diesel school buses are of particular concern. A recent study indicated that school
children are exposed to toxics levels five to 15 times the exposure to the rest of the population
because of the amount of time they spend on and around school buses. The Diesel Solutions
4-5 September 2004
Program is now concentrating on cleaning up the emissions from these buses. As a large urban-
rural county, air toxics will continue to be a primary health risk.
3, Greenhouse Gas (GHG) Emissions
Global climate change has and will continue to have local impacts. University of Washington
climate scientists predict that the Cascade snowpack will be 50 percent less in as little as 50 years
because of regional changes in climate. Likely results from this reduced snowpack are habitat
degradation, deforestation from drought and fires, and less water for drinking, irrigation and
hydropower generation. Recreational activities of fishing, skiing, boating, and rafting may be
significantly curtailed.
Beyond reduced snowpack, there will likely be coastline erosion from rising sea levels; more
droughts and floods from more erratic weather patterns; increased ozone levels from warmer
summers; heat-related deaths; and greater infestation of mosquito-related disease and forest
pests.
Climate scientists further assert that there will need to be a 60-80 percent reduction in GHG
emissions below 1990 levels if the climate is to be stabilized. As of 2003, global emissions are
already 10-20 percent above 1990 levels. Some permanent adverse effects from climate change
are underway.
Mobile sources, primarily on-road transportation, account for more than 50 percent of all GHG
emissions in King County. Transportation emissions in the United States usually account for
about 32 percent of GHG emissions. Therefore, transportation emissions present a distinctive
challenge for the region. Vehicles and fuels also are the biggest contributors to ozone, fine
particulates and toxics.
Strategies to reduce GHG emissions from transportation generally fall into two categories: reduce
vehicle GHG emissions and reduce vehicles miles traveled (VMT). For vehicle GHG emissions
reductions, again there are two general approaches: use more fuel efficient vehicles or use
alternative fuels. For efficient vehicles, Fleet Administration has been buying hybrid vehicles and
King County Metro has recently purchased 235 hybrid buses. King County currently is reviewing
the possibility of buying alternative fuels. For VMT reductions, King County will continue its work
to expand transit service, support demand management and transit-oriented development, as well
as variety of other approaches.
King County recognizes that the global warming challenge is worldwide in its scope, and that
much of the scientific community believes that potentially far reaching consequences to the
environment and to humankind's quality of life may result if this issue is not addressed effectively.
King County's actions are important contributors to addressing this issue; however, its global
nature will require cooperation across state and national boundaries.
4. King County Actions
In 2001, the King County Council and County Executive directed that there should be an inventory
of air pollutants and GHG emissions from King County government operations. In 2002, King
County completed its inventory. This inventory will continue to provide the focus for county
policies and projects.
The focus of King County air quality efforts is to engage in projects and changed practices that
reduce county emissions and promote policies that incorporate consideration of air quality
impacts. Examples of King County projects include the diesel solutions program and the
retrofitting of transit vehicles as well as solid waste and roads vehicles to use ultra-low sulfur
diesel; promoting the use of cleaner energy sources such as fuel cells at the Renton Wastewater
September 2004 4-6
Treatment Plant, and pursuing all cost-effective energy conservation programs in county facilities
to minimize the county's use of fossil-fuel-based energy sources.
King County has undertaken study of how land use planning affects transportation choices and
consequently air quality. The Land Use Transportation Air Quality and Health study will provide
information how land use patterns can affect air quality. The study has found that greenhouses
gas and regional air pollution decline steadily as housing density increases.
E-110
E-111
E-112
E-113
E-114
E-115
E-116
E-117
King County shall work to reduce air pollutants and greenhouse gas
emissions from its operations and seek to promote policies and programs
that reduce emissions in the region. Reducing ozone, fine particulates and
toxic emissions should be the top priority followed closely by greenhouse
gas emissions.
Motorized vehicle and other fuel burning engines related emissions are the
primary source of ozone, fine particulate, toxics and greenhouse gas
emissions in King County and therefore should be the primary focus for
emissions reduction.
A reduction in automobile use will have a direct benefit for improving air
quality and should include initiatives such as:
a. Increased transit services, options and alternatives;
b. Ridesharing; and
c. Innovative pricing programs to capture the true cost of driving.
Improving vehicle efficiency and after treatment technology, as well as
cleaning up petroleum fuels and fuel switching should be key strategies for
reducing motorized vehicle related emissions. Such strategies should
include:
a. Support for state and federal initiatives that improve fuel economy and
therefore reduce greenhouse gas emissions;
b. Continued investment into cleaner fuels and related emissions treatment
technologies;
c. Support for alternative fuels where financially practicable.
In addition to motorized vehicle related reductions, the county should
support initiatives that reduce emissions due to indoor and outdoor wood
burning consistent with the actions of PSCAA to control this source of public
h ea Ith th real.
King County should encourage its electricity suppliers to provide energy
efficiency, renewable energy and mitigation for electricity sources that are
powered by natural gas and coal. In addition, King County should encourage
the state to require new fossil fuel power plants to mitigate for their carbon
dioxide emissions.
King County will continue to evaluate its own maintenance and operations
practices including procurement for opportunities to reduce its own
emissions or emissions produced in the manufacturing of products.
King County should promote community designs that enable walking,
bicycling and public transit use thereby reducing greenhouse gas emissions
and regional air pollution.
4-7 September 2004
E-118 King County will continue to actively develop partnerships with the Puget
Sound Clean Air Agency, local jurisdictions, the state, and public, private,
not-for-profit groups to promote programs and policies that reduce
emissions of ozone, fine particulates, toxics, and greenhouse gases.
C. Water Resources
King County's water resources include Puget Sound, rivers, streams, lakes, wetlands, marine
nearshore and receiving waters of Puget Sound, and ground water. These resources provide
many beneficial functions, including fish and wildlife habitat, flood and erosion control, water
supply for agricultural, commercial, domestic and industrial use, energy production, transportation,
recreational opportunities and scenic beauty.
In order to preserve and enhance the water resources in King County, those resources must be
managed as an integrated system, not as distinct and separate elements. The hydrologic cycle
(the occurrence, distribution and circulation of water in the environment) is the common link
among the water resources and describes their interdependence.
Our use and modification of water resources and the surrounding terrestrial environment affects
how the hydrologic cycle functions and can cause unintended detrimental impacts such as
flooding, erosion, degradation of water quality, loss of fish and wildlife habitat, and loss of
archeological and traditional cultural resources that depend upon but do not damage natural
resources. In order to minimize adverse impacts on the water resources of King County and
ensure our continued ability to receive the benefits they provide, we need to promote responsible
land and water resource planning and use.
E-119
E-120
King County shall use incentives, regulations and programs to manage its
water resources (Puget Sound, rivers, streams, lakes, freshwater and marine
wetlands and ground water) and to protect and enhance their multiple
beneficial uses -including fish and wildlife habitat, flood and erosion control,
water quality control and sediment transport, water supply, energy
production, transportation, recreational opportunities and scenic beauty.
Use of water resources for one purpose should, to the fullest extent
practicable, preserve opportunities for other uses.
Development shall support continued ecological and hydrologic functioning
of water resources and should not have a significant adverse impact on water
quality or water quantity, or sediment transport and should maintain base
flows, natural water level fluctuations, groundwater recharge in Critical
Aquifer Recharge Areas and fish and wildlife habitat.
A watershed is an area that drains to a common outlet or identifiable water body such as Puget
Sound, a river, stream, lake or wetland. There are six major watersheds in King County (Cedar
River, Green River, Puget Sound, Skykomish River, Snoqualmie River and White River) divided
into 72 individual basins that, in turn, contain numerous individual water bodies with small
drainages. Surface and ground waters are. managed most effectively by considering potential
problems and solutions for an entire watershed. Because watersheds frequently extend into
several jurisdictions, effective planning and implementation must be.coordinated.
E-121 King County shall integrate watershed plans with marine and freshwater
surface water, ground water, drinking water and wastewater planning to
provide efficient water resource management.
E-122 As watershed plans are developed, zoning, regulations and incentive
programs may be developed, applied and monitored so that critical habitat in
September 2004 4-8
E-123
E-124
E-125
King County watersheds is capable of supporting sustainable and fishable
salmonid populations. Watershed-based plans should define how the natural
functions of watersheds critical to salmonids are protected so that the
quantity and quality of water entering the streams, lakes, wetlands and rivers
support salmonid spawning, rearing, resting, and migration.
King County shall protect and should enhance surface waters, including
streams, lakes, wetlands and the marine near shore and receiving waters of
Puget Sound, on a watershed basis by analyzing water quantity and quality
problems and their impacts to beneficial uses, including fish and wildlife
habitat and flood and erosion control. Conditions of and impacts to the
downstream receiving marine beaches and waters of Puget Sound shall be
included in watershed management efforts. King County shall continue to
participate in the Central Puget Sound Water Resource Planning effort.
King County should protect and enhance the natural environment in those
areas recommended as Aquatic Reserves by Washington State Department of
Natural Resources. This should include participation in management
planning for the aquatic reserves and working with willing landowners
adjacent to the reserve on restoration and acquisition projects which
enhance the natural environment.
Responsibility for the costs of watershed planning and project
implementation including water quality, flood hazard reduction and fisheries
habitat protection, should be shared between King County and other
jurisdictions within a watershed.
King County contains a number of wetlands, river and stream reaches that are important to the
viability of fish and wildlife populations and are therefore considered biological, social and
economic resources. Some resource areas were previously identified through basin plans and
other resource inventory efforts, and are categorized as either Regionally Significant Resource
Areas (RSRAs) or Locally Significant Resource Areas (LSRAs). RSRAs contribute to the
resource base of the entire Puget Sound region by virtue of exceptional species and habitat
diversity and abundance when compared to basins of similar size and structure elsewhere in the
region. These areas may also support rare, endangered or sensitive species, including
threatened salmonids. LSRAs contribute to the aquatic resources within a specific basin, when
compared to aquatic and terrestrial systems of similar size and structure elsewhere in the basin.
They also provide wetland and stream habitat that is important for wildlife and salmonid diversity
and abundance within the basin. As Water Resource Inventory Area plans are prepared in
compliance with the Endangered Species Act, additional resource areas will be identified and
analyzed to determine appropriate levels of resource protection.
E-126
E-127
Watershed management plans, Water Resource Inventory Area plans, flood
hazard reduction plans and master drainage plans should apply a tiered
system of protection that affords a higher standard of protection for more
significant resources. Resource categories should include Regionally
Significant Resource Areas (RSRAs), Locally Significant Resource Areas
(LSRAs), Fish and Wildlife Habitat Conservation Areas, and remaining
resources. Where appropriate, additional designations shall be made as
additional information on environmental functions becomes available.
Regionally Significant Resource Areas (RSRAs) and Locally Significant
Resource Areas (LSRAs) shall be mapped, designated by ordinance and
protected at appropriate levels as part of early and long-term actions towards
salmon conservation and recovery under the ESA. These designations shall
4-9 September 2004
be based on adopted basin plans or habitat/resource assessments completed
for the Waterways 2000 program, but may be changed or new areas may be
designated pursuant to recommendations of Water Resource Inventory Area
plans. The Executive shall study the standards of protection needed for
RSRAs and LSRAs.
King County's Shoreline Management Master Program (Title 25 of the King County Code) is a
functional plan developed in compliance with the Washington State Shoreline Management Act of
1971. The master program protects streams with a mean annual flow of 20 cubic feet or more
per second, lakes that are 20 acres or more in size, the marine shoreline of Puget Sound and
wetlands associated with these systems.
E-128 Development within designated shoreline environments shall preserve the
resources and ecology of the water and shorelines, avoid natural hazards,
promote visual and physical access to the water, protect ESA listed species
and their critical habitat, and preserve archeological, traditional cultural
resources, shellfish resources, and navigation rights. Protection of critical
areas shall take priority over visual values and physical access.
Puget Sound was included in the National Estuary Program in March 1988. The National Estuary
Program requires that a comprehensive conservation and management plan for Puget Sound
recommend actions to restore and protect the estuary. The 1994 Puget Sound Water Quality
Management Plan is the federally approved comprehensive conservation and management plan
for Puget Sound.
E-129 King County shall implement the Puget Sound Water Quality Management
Plan to restore and protect the biological health and diversity of the Puget
Sound Basin.
Rivers, streams, lakes and wetlands must be protected from the adverse impacts of urbanization
and land use to continue functioning in a beneficial manner. Because urbanization increases
stormwater runoff, control of the quantity and quality of stormwater runoff is critical. Unmitigated
stormwater runoff can cause erosion, sedimentation and flooding with resulting adverse impacts
on water quality, fish and wildlife habitat, property and human safety. In addition, stormwater
runoff can carry pollutants such as oil, heavy metals, fertilizers, herbicides, pesticides and animal
wastes into waters. Sedimentation from soil disturbed by clearing, grading, farming and logging
can reduce river or stream channel capacity, fill lakes and wetlands, and smother aquatic life and
habitat.
Methods of stormwater management include clearing restrictions, retention/detention, low-impact
development methods, discharge and infiltration standards, and best management practices.
E-130 Stormwater runoff shall be managed through a variety of methods, with the
goal of limiting impacts to aquatic resources, reducing the risk of flooding,
protecting and enhancing the viability of agricultural lands and promoting
groundwater recharge. Methods of stormwater management shall include
temporary erosion and sediment control, flow control facilities, water quality
facilities as required by the Surface Water Design Manual, and best
management practices as described in the Stormwater Pollution Control
Manual. Runoff caused by development shall be managed to prevent adverse
impacts to water resources and farmable lands. Regulations shall be
developed for lands outside of the Urban Areas that favor nonstructural
stormwater control measures when feasible including: vegetation retention
and management; clearing limits; limits on actual impervious surface and
September 2004 4-10
impacting impervious surface; low-impact development methods that
disburse runoff into native vegetation; and limits on soil disturbance.
The Federal Clean Water Act requires states to prepare a list of water bodies that do not meet
water quality standards. This list, known as the 303(d) list, is prepared for Washington State by
the State Department of Ecology, and must be submitted to the U.S. Environmental Protection
Agency (EPA) every two years. The water bodies on the list consist of "water quality limited"
estuaries, lakes, rivers and streams that fall short of state surface water quality standards, and are
not expected to achieve standards after implementation of technology-based controls. These
standards are intended to ensure that our waters can be beneficially used for purposes we all
enjoy, from fishing, swimming, boating, and drinking to industrial and agricultural purposes, and
fish habitat. The beneficial uses that are intended to be protected by water quality standards are
those that have existed or could have existed in the waterbody from November 1975 or later.
EPA requires that states set priorities for cleaning up impaired waters and establish a Total
Maximum Daily Load (TMDL) for each. A TMDL, or water cleanup plan, entails analysis of how
much pollution a waterbody can receive and still support its beneficial uses. The cleanup plan
also includes recommendations for controlling pollution sources and a monitoring plan to test the
plan's effectiveness. TMDL's have been approved by EPA for the Snoqualmie River, Lake
Ballinger, Pipers Creek, Lake Fenwick, Lake Sawyer, and the Duwamish River and Lower Green.
A complete listing of TMDLs and the 303(d) list can be found on the Department of Ecology's web
site at http://www.ecy.wa.gov/.
E-131 Surface waters designated by the state as Water Quality Impaired under the
Clean Water Act (water bodies included on the State 303(d) list) shall be
improved through monitoring, source controls, best management practices,
enforcement of existing codes, and Total Maximum Daily Load plans
(TMDLs). The water quality of all other state-classified water bodies shall be
maintained or improved through these same measures, and other additional
measures that may be necessary to ensure there is no loss of existing
beneficial uses. Any beneficial uses lost since November 1975 shall be
restored wherever practicable, consistent with the Federal Clean Water Act.
There are approximately 3,126 miles of rivers and streams in King County. The river and stream
channels, the surrounding riparian (streamside) areas and upland areas all contribute to the
functioning and integrity of rivers and streams. Many rivers and streams provide critical habitat for
many species of wildlife and fish, including salmonids.
E-132 River and stream channels, stream outlets, headwater areas, and riparian
corridors should be preserved, protected and enhanced for their hydraulic,
hydrologic, ecological and aesthetic functions, including their functions in
providing woody debris sources to salmonid-bearing streams.
There are approximately 700 lakes in King County ranging in size from less than one acre to Lake
Washington. These lakes provide critical habitat for many species of fish and wildlife, including
salmonids, as well as recreational opportunities and scenic beauty. Development near lakes can
alter their functioning and lead to eutrophication (increases in nutrients). Eutrophication promotes
the excessive growth of plant and animal life with the eventual depletion of oxygen levels caused
by decay of the excess organic matter.
E-133 Lakes should be protected through management of lake watersheds and
shorelines. Lakes sensitive to nutrients shall be protected through the
management of nutrients that stimulate algae blooms and aquatic plant
growth. Where sufficient information is available, measurable standards for
lake quality should be set and management plans established to meet the
4-11 September 2004
standards. Formation of lake management districts or other financing
mechanisms should be considered to provide the financial resources
necessary to support actions for protection of sensitive lakes.
Wetlands are valuable natural resources in King County. They include shallow or deep marshes,
bogs, ponds, wet meadows, forested and scrub-shrub communities and other lands supporting a
prevalence of vegetation adapted to saturated soils. Many of the larger wetlands in King County
are mapped in the County's Sensitive Areas Map Folio, and their vegetation, hydrology and wildlife
are briefly described in the King County Wetlands Inventory.
E-134
E-135
King County shall use as minimum standards the Washington State Wetlands
Identification and Delineation Manual, 1997, or its successor which is
adopted by the King County Council and is the scientifically accepted
replacement methodology based on better technical criteria and field
indicators. King County shall categorize wetlands using the Washington
State Wetland Rating System for Western Washington or its successor.
King County shall work with other jurisdictions and federally recognized
tribes to establish uniform countywide wetlands policies that provide
protection of both regionally and locally unique wetlands.
Wetlands are productive biological systems, providing habitat for fish and wildlife. They may
serve as outdoor classrooms for scientific study. Some are used for hiking, hunting, and fishing.
Wetlands also store flood waters and control runoff, thereby reducing flooding, downstream
erosion and other damage. Further, wetlands protect water quality by trapping sediments and
absorbing pollutants. They discharge ground water, making it available to plants and animals.
Wetlands store peak flows and discharge to streams in dry periods, thus enabling fish and other
riparian animal populations to survive. These wetland functions need consideration from a
watershed perspective. Measures to protect wetland functions and values need to be taken at
both the site-specific and watershed scale. In the urban area, land use authority is often shared
by multiple jurisdictions at the scale of a drainage basin. Similarly, efforts to protect and restore
wetlands may be sponsored by multiple parties, including local governments.
E-136
E-137
King County's overall goal for the protection of wetlands is no net loss of
wetland functions and values within each drainage basin. Acquisition,
enhancement, regulations, and incentive programs shall be used
independently or in combination with one another to protect and enhance
wetlands functions and values. Watershed management plans, including
Water Resource Inventory Area plans, should be used to coordinate and
inform priorities for acquisition, enhancement, regulations, and incentive
programs within unincorporated King County to achieve the goal of no net
loss of wetland functions and values within each drainage basin.
Development adjacent to wetlands shall be sited such that wetland functions
and values are protected, an adequate buffer around the wetlands is
provided, and significant adverse impacts to wetlands. are prevented.
The functions and values of a wetland will change as land use surrounding the wetland changes.
Development-related changes in forest cover and impervious surface affect stormwater runoff
patterns, flooding, water quality, and wetland hydrology. Fragmentation of habitat is considered
the greatest threat to native biodiversity. Wetlands in the Urban Growth Area will experience the
greatest reduction in the number of native animals and plants due to habitat fragmentation.
Protecting native species biodiversity depends upon maintaining biological linkages, supporting
the natural processes (like hydrology) that shape wetland habitat, and preventing fragmentation of
September 2004 4·12
wetland habitats. Small wetlands strategically located between other wetlands may provide
important biological links between other, higher quality wetlands. Wetlands adjacent to habitat
networks also are especially critical to wildlife functions and should receive special consideration
in planning land use.
E-138
E-139
E-140
E-141
E-142
E-143
Areas of native vegetation that connect wetland systems should be
protected. Whenever effective, incentive programs such as buffer averaging,
density credit transfers, or appropriate nonregulatory mechanisms shall be
used.
The unique hydrologic cycles, soil and water chemistries, and vegetation
communities of bogs and fens shall be protected through the use of
incentives, acquisition, best management practices, and implementation of
the King County Surface Water Design Manual to control and/or treat
stormwater within the wetland watershed.
Public access to wetlands for scientific, recreational use, and traditional
cultural use is desirable, providing that public access trails are carefully
sited, sensitive habitats and species are protected, and hydrologic continuity
is maintained.
Regulatory approaches for protecting wetland functions and values,
including the application of wetland buffers, should consider wetland
functions and values, intensity of surrounding land uses, and basin
conditions. King County should continue to review wetland research and
evaluate the need for changes in its wetland protection programs.
Enhancement or restoration of degraded wetlands may be allowed to
maintain or improve wetland functions and values provided that all wetland
functions are evaluated in a wetland management plan, and adequate
monitoring, code enforcement and evaluation is provided and assured by
responsible parties. Restoration or enhancement must result in a net
improvement to the functions of the wetland system. Technical assistance to
small property owners should be considered.
Alterations to wetlands may be allowed to:
a. Accomplish a public agency or utility development;
b. Provide necessary utility, stormwater tightline and road crossings; or
c. Avoid a denial of all reasonable use of the property, provided all wetland
functions are evaluated, the least harmful and reasonable alternatives are
pursued, affected significant functions are appropriately mitigated, and
mitigation sites are provided with monitoring.
When adverse impacts cannot be avoided, compensatory mitigation may be allowed. This means
the replacement of project-induced losses of wetland functions and values will be permitted
through wetland creation, restoration or enhancement. The county recognizes that, especially in
the Urban Growth Area, allowing alteration of small Category IV wetlands in exchange for
compensatory mitigation contributes to a larger connected wetland system and may achieve
greater resource protection.
E-144 A small Category IV wetland that is less than 2,500 square feet and that is not
part of a wetland complex may be altered to move functions to another
wetland on site as part of an approved mitigation plan.
4-13 September 2004
E-145
E-146
E-147
Mitigation sites should replace or augment the functions and values to be
lost as a result of the project proposal. Wetland mitigation proposals should
be approved if they would result in improved overall wetland functions and
values within a drainage basin. All wetland functions and values should be
considered. Mitigation sites should be located strategically to alleviate
habitat fragmentation, and avoid impacts to and prevent loss of farmable land
within Agricultural Production Districts.
Mitigation projects should contribute to an existing wetland system or
restore an area that was historically a wetland. The goal for these mitigation
projects is no net loss of wetland functions and values within a drainage
basin.
Land used for wetland mitigation should be preserved in perpetuity.
Monitoring and maintenance in conformance with King County standards
should be provided by the project proponent until the success of the site is
established.
Mitigation banks are a form of regional compensatory mitigation, with the goal providing greater
resource protection and benefit to the public. A mitigation bank allows for the consolidation of
multiple, small mitigation projects into a large-scale wetland complex, resulting in economies of
scale in planning, implementation and maintenance. Consolidation also can result in wetlands of
greater value because of their size and the commitment to long-term management. Mitigation
banking allows a project proponent to generate bank credits by contributing to the creation or
restoration of the bank site.
E-148
E-149
The county in partnership with jurisdictions and interested parties should
implement the wetland mitigation banking program.
Creation of wetland mitigation banks is not allowed in the Agricultural
Production District when the purpose is to compensate for filling wetlands
for development outside the APD.
Floodplains are lands adjacent to lakes, rivers and streams that are subject to periodic flooding.
Floodplains naturally store flood water, protect water quality and are valuable for recreation,
agriculture and fish and wildlife habitat. Floodplains also provide a deposition zone for sediments
mobilized by rivers and streams. Wetlands are often an integral part of floodplains. Floodplains
are designated based on the predicted frequency of flooding for a particular area. For example, a
1 DO-year floodplain is a land area that has a one percent probability of experiencing flooding in
any given year.
Development can reduce the floodplain's ability to store and convey floodwaters, thereby
increasing the velocity and depth of floodwaters in other areas. In addition, floodplain
development often occurs at the expense of important fish and wildlife habitat. King County has
adopted the Flood Hazard Reduction Plan to provide guidance for decisions related to land use
and flood control activities.
E-150 The existing flood storage and conveyance functions and ecological values
of floodplains, wetlands, and riparian corridors shall be protected, and
should, where possible, be enhanced or restored.
E-151 King County's floodplain land use and floodplain management activities shall
be carried out in accordance with the King County Flood Hazard Reduction
Plan.
September 2004 4·14
Protecting ground water is an important regional issue because ground water provides
approximately 30 percent of the water used in King County. The natural hydrologic system can be
altered by development practices and overuse of the aquifer. The result may be depletion of
aquifers. Ground water is also subject to contamination from human activity. Once a source of
ground water is contaminated it may be lost forever. The cost of protection is considerably less
than the cost of remediation and replacement.
E-152
E-153
E-154
E-155
E-156
E-157
King County shall identify areas in unincorporated King County that are
considered Critical Aquifer Recharge Areas and maintain a map that
designates these areas. The county shall update this map periodically with
new information from adopted groundwater and wellhead protection studies
and other relevant sources.
King County should protect the quality and quantity of ground water
countywide by:
a. Implementing adopted Groundwater Management Plans;
b. Reviewing and implementing approved Wellhead Protection Programs in
conjunction with cities, state agencies and groundwater purveyors;
c. Developing, with affected jurisdictions, best management practices for
development and for forestry, agriculture, and mining operations based
on adopted Groundwater Management Plans and Wellhead Protection
Programs. The goals of these practices should be to promote aquifer
recharge quality and to strive for no net reduction of recharge to
groundwater quantity; and
d. Refining regulations to protect Critical Aquifer Recharge Areas and well-
head protection areas.
King County should protect groundwater recharge quantity by promoting
methods that infiltrate runoff where site conditions permit, except where
potential groundwater contamination cannot be prevented by pollution
source controls and stormwater pretreatment.
In making future zoning and land use decisions which are subject to
environmental review, King County shall evaluate and monitor groundwater
policies, their implementation costs, and the impacts upon the quantity and
quality of ground water. The depletion or degradation of aquifers needed for
potable water supplies should be avoided or mitigated, and the need to plan
and develop feasible and equivalent replacement sources to compensate for
the potential loss of water supplies should be considered.
King County should protect ground water in the Rural Area by:
a. Preferring land uses that retain a high ratio of permeable to impermeable
surface area and that maintain or augment the infiltration capacity of the
natural soils; and
b. Requiring standards for maximum vegetation clearing limits, impervious
surface limits, and, where appropriate, infiltration of surface water. These
standards should be designed to provide appropriate exceptions
consistent with Policy R-231.
King County shall use the Vashon-Maury Island Rapid Rural Reconnaissance
Report, the ongoing Vashon-Maury Island Water Resources Evaluation and
other studies to direct appropriate policy and planning actions that may be
necessary to protect the groundwater and surface water resources. Pending
completion and implementation.of the evaluation and studies, applicants for
4·15 September 2004
new on-site sewage disposal permits on Vashon-Maury Islands shall be
required to demonstrate the following:
a. That the location of the on-site sewage disposal system is not within 200
feet of the documented boundaries of upper-aquifer groundwater
contamination or a surface water body or stream;
b. That the new on-site sewage disposal system is designed to replace an
existing disposal system and is likely to reduce impacts to ground and
surface waters; or
c. That, if the size or features of a parcel make it infeasible to satisfy the
200-foot setback provided in subsection (a) above, the proposed onsite
sewage disposal system uses the best available technology to reduce
potential impacts to ground and surface waters. In such circumstances,
the county may require periodic monitoring.
D. Erosion and Landslide Hazards
King County is located on the active, tectonic Pacific "Ring of Fire," which is characterized by
numerous, dynamic geologic processes that include frequent earthquakes and recurring volcanic
eruptions. The relatively recent glacial history has left numerous steep and unstable hillsides
throughout the county. Because of these steep and unstable hillsides, many areas of the county
are prone to naturally occurring landslides and tree falls. Snow avalanches are also a common
occurrence in the Cascade Mountains in Eastern King County. Often times the result of these
naturally occurring events can be beneficial to the environment, by providing gravel and woody
debris in streams and rivers, and continuing the process of natural regeneration. Salmon need
gravel for spawning and in-stream debris for cover and to provide shade and regulate
temperature. King County must balance the positive benefits of these natural occurrences with
any adverse impacts that pose a threat to public health and safety. The county must also strike a
balance between allowing naturally occurring landslides and erosion, and the need to prevent the
unnatural acceleration of landslides and erosion due to development activities.
Coal mines have created additional areas of subsidence and instability in addition to those which
occur naturally. When human activity occurs in areas subject to such active geologic processes,
the potential consequences to life, property and environmental integrity can be enormous. If
geologic processes are recognized and appropriately addressed in the course of development
activities, adverse consequences can be substantially reduced if not completely eliminated. King
County maintains inventories and maps of geologic hazards in the King County Sensitive Areas
Map Folio.
1. Erosion Hazard Areas
Virtually any area in King County can experience soil erosion if subjected to inappropriate grading
and construction practices. The U.S. Department of Agriculture Soil Conservation Service has
identified certain soil types in King County as being especially subject to erosion, if disturbed. The
approximate extent of these areas is shown in the King County Sensitive Areas Map Folio. These
Erosion Hazard Areas may not be well suited to high-density developments and intensive land
uses because of the sensitivity of these soils to disturbance.
E-158 Grading and construction activities shall implement erosion control best
management practices and other development controls as necessary to
reduce sediment and pollution discharge from construction sites to minimal
levels.
E-159 Land uses permitted in Erosion Hazard Areas shall minimize soil disturbance
and should maximize retention and replacement of native vegetative cover.
September 2004 4-16
E-160 Slopes with a grade of 40 percent or more shall not be developed unless the
risks and adverse impacts associated with such development can be reduced
to a nonsignificant level. No-disturbance zones shall be designated where
basin plans identify the need to prevent erosion damages in areas that are
extremely sensitive to erosion impacts. Properly designed stormwater
tightlines may be allowed within designated no-disturbance zones.
Vegetation is an important component of the natural environment. This general term refers to all
plant life growing at, below or above the soil surface. It includes trees, shrubs, herbs, grasses and
aquatic plants.
Vegetation, especially forests, provides many significant ecological functions. Vegetation
absorbs, filters and slows surface water flow. This is particularly important over aquifer recharge
areas. Native vegetation also provides wildlife habitat to which native species are well adapted.
Forests are key components in atmospheric cycles; they absorb carbon dioxide, produce oxygen
and filter particulate matter. Additionally, they absorb noise and are aesthetically pleasing.
Noxious weeds are nonnative invasive plants that pose a threat to health and safety, agriculture,
wildlife, wetlands and recreational areas. They tend to spread in areas that have been disturbed
by urban development and agriculture and are difficult to eradicate once they become established.
Without natural predators, some noxious weeds can displace native plant communities, reducing
plant diversity. Invasive plants also decrease the quality of wildlife habitats, reduce visual quality,
and increase maintenance and production costs for natural resource managers and farmers.
E-161 King County should protect native plant communities by encouraging
management and control of nonnative invasive plants, including aquatic
plants. Environmentally sound methods of vegetation control should be
used to control noxious weeds.
E-162 Through training and other programs, King County should actively
encourage the use of environmentally safe methods of vegetation control.
Herbicide use should be minimized. King County should be a good steward
of public lands and protect water quality, by reducing the use of insecticides,
herbicides and fungicides through the use of integrated pest and vegetation
management practices.
E-163 The use of native plants should be encouraged in landscaping requirements
and erosion control projects, and in the restoration of stream banks, lakes,
shorelines, and wetlands.
E-164 In response to watershed-based salmon conservation Water Resource
Inventory Area plans and as part of King County's continued basin planning
and stewardship programs, King County may adopt vegetation retention
goals for specific drainage basins. These goals should be consistent with
Policy R-232, as applicable. The county should adopt incentives and
regulations to attain these goals, and the county should monitor their
effectiveness.
2. Landslide and Avalanche Hazard Areas
Certain hillsides in King County are either naturally unstable or susceptible to instability when
disturbed. These hillsides contain slopes greater than 15 percent, are underlain by impermeable
soils, and are subject to seepage. They also include areas that have experienced landslides in
the past and have slopes that are being undermined by stream or beach erosion. Construction in
these areas is expensive and difficult. Landslides on such slopes following development can
4-17 September 2004
result in enormous public and private costs and severe threats to human health and safety. Such
landslides can also cause severe natural resource damage.
Many of the mountainsides in the Cascade Range in Eastern King County are subject to snow
avalanches during the winter. Such avalanches are destructive and can be deadly. King County
supports all efforts to monitor and share information regarding avalanche dangers and to alert the
public of those dangers.
E-165 Avalanche or Landslide Hazard Areas should not be developed unless the
risks and adverse impacts associated with such development can be reduced
to a nonsignificant level. Development proposed in or adjacent to avalanche
or landslide hazard areas shall be adequately reviewed and mitigated to
ensure development does not increase landslide or erosion hazards that
would adversely impact downstream properties or natural resources.
3. Coal Mine Hazard Areas
King County has a long and varied history of underground and surface coal mining. Some coal
mining was conducted by large, well-capitalized mining companies which used methods such as
detailed underground and surface mapping and protection of surface improvements. Other mines
were small operations or remining operations that sought to maximize coal extraction with less
regard for surface impacts or mapping. Some intensively developed areas of King County are
located over abandoned underground coal workings, including Talbot Hill and the north Benson
Hill of Renton, the Spring Glen area around Cascade Vista, East Fairwood, Black Diamond,
southwest Issaquah, and the Newcastle/Coal Creek area.
The greatest dangers to people, wildlife and surface facilities typically exist around mine portals,
timber chutes, air shafts, and workings which have collapsed to the surface. Other areas were
deep mined by "room and pillar" mining techniques in which "pillars" of coal were left to provide
support for the mining of adjacent "rooms." Once abandoned, pillars would collapse and rooms of
mined-out coal would fill with collapsed roof material, coal debris and water. Regional
downwarping of these areas was generally not observable and usually happened in the early
years following mining of a section. Deep mined areas with a high ratio of overburden/cover-to-
void usually present no hazards for surface development. However, areas with low
overburden/cover-to-void ratio present higher risks and may require more advanced investigations
and construction techniques for development. Mine portals, timber chutes, airshafts, and
workings which have collapsed to the surface require the greatest need for detailed engineering
studies to ensure that these sites are safe for new, productive use.
E-166 King County encourages the elimination of coal mine hazard areas and will
work with public and private property owners and the Office of Surface
Mining, Reclamation, and Enforcement to eliminate hazards and return lands
to their highest productive uses. Land use plans and development activities
should reflect the potential hazards in these areas. Residential, commercial,
and industrial development may occur in coal mine hazard areas following
study and engineering reports which detail the extent of the hazards, if any,
and mitigation. Significant hazards associated with abandoned coal mining
workings should be eliminated or mitigated so the site is safe using
appropriate criteria to evaluate the proposed subsequent use. King County
recognizes that most areas underlain by deep underground mining may be
suitable for new development. Landowners and their consultants may be
required to provide studies and reports with recommendations from licensed,
professional engineers. Proposed surface facilities over some hazard areas
may need to incorporate special design and performance tolerances for
structures and infrastructure improvements. The location and
September 2004 4-18
•
declassification of coal mine hazard features should be shown on recorded
plat maps or site plans of the property. When new information regarding the
location of coal mine hazard areas is discovered, it should be added to or
deleted from existing maps and databases that record coal mine hazard area
information.
King County is an earthquake-prone region subject to ground shaking, seismically induced
landslide and liquefaction of soil. Areas with low-density soils are likely to experience greater
damage from earthquakes. Areas in King County with a high potential for seismic induced
subsidence, landslide, and other damages are shown in the King County Sensitive Areas Map
Folio under seismic and landslide hazard areas.
E-167
E-168
In areas with severe seismic hazards, special building design and
construction measures should be used to minimize the risk of structural
damage, fire and injury to occupants and to prevent post-seismic collapse.
King County should support efforts to model the effects of a mudflow
comparable to the prehistoric mudflow which occurred in the White River
drainage basin.
E. Fish and Wildlife
It is King County's goal to conserve fish and wildlife resources in the county and to maintain
countywide biodiversity. This goal may be achieved through implementation of several broad
policy directions that form an integrated vision for the future. Each of the pieces is necessary for
the whole to be successful. The policy objectives are to 1) identify and protect critical fish and
wildlife habitat conservation areas, 2) link those critical habitat areas and other protected lands
through a network system, and 3) integrate fish and wildlife habitat and conservation goals into
new and existing developments. Conservation of biodiversity is necessary if wildlife benefits
currently enjoyed by residents of the county are to be enjoyed by future generations.
E-169
E-170
E-171
The county shall strive to maintain the existing diversity of species and
habitats in the county. In the Urban Growth Area, King County should strive
to maintain a quality environment which includes fish and wildlife habitats
that support the greatest diversity of native species consistent with the
density objectives. The county should maximize wildlife diversity in the
Rural Area.
Fish and wildlife should be maintained through conservation and
enhancement of terrestrial, air, and aquatic habitats.
Habitats for species which have been identified as endangered, threatened,
or sensitive by the state or federal government shall not be reduced and
should be preserved. In the Rural Area and Natural Resource Lands, habitats
for candidate species identified by the county, as well as species identified as
endangered, threatened, or sensitive by the state or federal government shall
not be reduced and should be preserved.
The Growth Management Act requires jurisdictions to designate Fish and Wildlife Habitat
Conservation Areas for protection. The Washington Administrative Code (WAC) sets out
guidelines that jurisdictions must consider when designating these areas. As set forth in the WAC
guidelines, Fish and Wildlife Habitat Conservation Areas include:
a. Areas with which endangered, threatened, and sensitive species have a primary
association;
b. Habitats and species of local importance;
4-19 September 2004
c. Commercial and recreational shellfish areas;
d. Kelp and eel grass beds; herring and smelt spawning areas;
e. Naturally occurring ponds under 20 acres and their submerged aquatic beds that provide
fish or wildlife habitat;
f. Waters of the state;
g. Lakes, ponds, streams, and rivers planted with game fish by a governmental or tribal
entity; or
h. State natural area preserves and natural resource conservation areas.
It is important to note that for some species, mere presence is not considered significant.
Significant habitats, for some species, are those areas that may be limited during some time of
the year or stage of the species life cycle.
King County has reviewed these guidelines and has developed policies E-172 through E-176 that
address the various species included in the WAC guidelines. These policies recognize the tiered
listing of these species and their habitats as defined by the United States Fish and Wildlife Service
and the Washington State Department of Fish and Wildlife. These policies also recognize the
need to regularly review the information developed on species and habitats and amend the tiered
listing as appropriate.
E-172
E-173
September 2004
King County shall designate and protect, through measures such as
regulations, incentives, capital projects or purchase, the following Fish and
Wildlife Habitat Conservation Areas found in King County:
a. Habitat for federal or state listed Endangered, Threatened or Sensitive
species;
b. Habitat for Salmon ids of Local Importance: kokanee/sockeye/red salmon,
chum salmon, coho/silver salmon, pink salmon, coastal resident/searun
cutthroat, rainbow trout/steelhead, bull trout, Dolly Varden, and pygmy
whitefish, including juvenile feeding and migration corridors in marine
waters;
c. Habitat for Raptors and Herons of Local Importance: osprey, black-
crowned night heron, and great blue heron;
d. Commercial and recreational shellfish areas;
e. Kelp and eelgrass beds;
f. Herring, sand lance and smelt spawning areas;
g. Wildlife habitat networks designated by the county, and
h. Riparian corridors.
King County shall also protect the habitat for the red-tailed hawk and for
candidate species, as listed by the Washington Department of Fish and
Wildlife, found in King County outside of the Urban Growth Area.
King County should protect the following species of local importance, as
listed by the Washington Department of Fish and Wildlife or listed by King
County, on lands outside of the Urban Growth Area, where they are likely to
be most successful. Protection should be accomplished through
regulations, incentives or purchase.
Species of local importance are:
a. Mollusks -Freshwater mussel, Geoduck clam and Pacific oyster;
b. Crustaceans -Dungeness crab and Pandalid shrimp;
c. Echinoderms -Red urchin;
d. Fish -White sturgeon, Pacific herring, channel catfish, longfin smelt,
surfsmelt, Pacific cod, Pacific whiting, black rockfish, copper rockfish,
4-20
•
E-174
E-175
E-176
quill back rockfish, yelloweye rockfish, lingcod, Pacific sand lance,
English sole, and rock sole;
e. Birds -Trumpeter swan, Tundra swan, Snow goose, Band-tailed pigeon,
Brant, Harlequin duck, Blue grouse, Mountain quail, and Western
bluebird; and
f. Mammals -Marten, mink, Columbian black-tailed deer, elk, and mountain
goat.
King County should protect the following priority habitats listed by the
Washington Department of Fish and Wildlife that are not otherwise protected
by policies and codes. Protection should be accomplished through
regulations, incentives or purchase. Priority habitats are: caves, cliffs,
consolidated marine/estuarine shorelines, estuary, old growth/mature forest,
unconsolidated marine/estuarine shorelines, snag-rich areas, and talus
slopes.
Development proposals should be assessed for the presence of species of
local importance. A comprehensive assessment should follow a standard
procedure or guidelines and shall occur one time during the development
review process.
King County should regularly review the Washington State Department of
Fish and Wildlife's list of Priority Species and other scientific information on
species of local importance, and evaluate whether any species should be
added to or deleted from the list in Policies E-173 and E-174. Any additions
or deletions should be made through the annual amendment process for the
comprehensive plan.
Existing buffer requirements for streams and wetlands are not intended to, and do not, always
adequately protect wildlife resources in those sensitive areas. Areas with critical wildlife resources
may need larger buffers to protect the resource.
E-177 Stream and wetland buffer requirements may be increased to protect species
of local importance, as listed in this chapter, and their habitats, as
appropriate. Whenever possible, density transfers and/or buffer averaging
should be allowed.
Salmon are particularly important because of their significance to local and regional character,
federally recognized tribes and the fisheries industry. Several salmon stocks within King County
and other areas of Puget Sound are in a serious state of decline. Several salmon stocks within
King County have been or are about to be listed under the Endangered Species Act. The most
effective way to protect and enhance native fish populations is through protection of those river
and stream channels, riparian corridors, lakes, wetlands, headwaters and watersheds that provide
or impact spawning and rearing habitat, food resources and fish passage. Intermittent streams
also can be critical to native fish populations. Hatcheries and other artificial propagation facilities
that are managed to protect the abundance, productivity, genetic diversity, and spatial distribution
of native salmon remain critical to maintaining sustainable salmon stocks and harvest
opportunities while habitat protection and restoration measures for salmon are implemented.
E-178 King County should protect salmonid habitats by ensuring that land use and
facility plans (transportation, water, sewer, electricity, gas) include riparian
and stream habitat conservation measures developed by the county, cities,
federally recognized tribes, service providers, and state and federal agencies.
Project review of development proposals within basins that contain
hatcheries and other artificial propagation facilities that are managed to
4-21 September 2004
protect the abundance, productivity, genetic diversity, and spatial
distribution of native salmon and provide harvest opportunities should
consider significant adverse impacts to those facilities.
Protection of isolated blocks of habitat will not adequately protect wildlife in King County. Critical
wildlife habitats and refuges need to be connected across the landscape through a system of
habitat networks. Some areas may be important because they connect other areas together.
Network width is related to requirements of desired wildlife species, length of network segment
and other desired uses within the network. Wider corridors will be required for larger species if
the distance between refuges is great or if multiple uses, such as public access and trails, are
desired. Since it may not be possible to protect wide corridors in the Urban Growth Area, it may
not be possible to accommodate larger wildlife species in all areas. Networks will address some
of the problems of habitat fragmentation for smaller species within the Urban Growth Area.
Potential linkages are identified on the Wildlife Network and Public Ownership Map. Open spaces
set aside during subdivision of land should be located to make connections with larger off site
systems. This approach will also benefit other open space goals.
E-179
E-180
Dedicated open spaces and designated sensitive areas help provide wildlife
habitat. Habitat networks for threatened, endangered and priority species of
local importance, as listed in this chapter shall be designated and mapped.
Habitat networks for other priority species in the Rural Area should be
designated and mapped. Planning should be coordinated to ensure that
connections are made with adjacent segments of the network. King County
should provide incentives for new development within the networks to
incorporate design techniques that protect and enhance wildlife habitat
values.
King County shall also protect the habitat for candidate species, as listed by
the Washington Department of Fish and Wildlife, found in King County
outside of the Urban Growth Area.
King County should work with adjacent jurisdictions, state and federal
governments and federally recognized tribes during development of land use
plans, Water Resource Inventory Area plans, and site development reviews to
identify and protect habitat networks at jurisdictional boundaries.
A key element in a comprehensive wildlife protection program is the integration of wildlife and
habitats into developments of all types. Protection of many types of wildlife does not have to be at
odds with many types of development. Urban multifamily projects, industrial developments, new
school facilities and rural open space projects all provide opportunities to enhance wildlife
amenities. Residential developers and businesses have been able to use wildlife in marketing
strategies to attract more potential homeowners, renters and quality employees.
Techniques such as minimizing clearing during site preparation, using native plant species in
required buffers, landscaping, using bridges rather than culverts to cross streams and innovative
site design can be used to promote wildlife and minimize problems with nuisance wildlife. Other
plan elements, such as open space, road system design and housing density, also have related
impacts on the remaining wildlife values that must be considered.
Benefits to wildlife are enhanced if screening and landscaping is composed of native vegetation.
Retention of natural vegetation can provide the same wildlife and aesthetic benefits at a lower
cost.
September 2004 4-22
E-181
E-182
E-183
New development should, where possible, incorporate native plant
communities, both through preservation of existing native plants into the site
plan, and addition of new native plants.
The county should be a good steward of public lands and should integrate
fish and wildlife habitats into capital improvement projects whenever
feasible. Fish and Wildlife Habitat Conservation Areas should be protected
and where possible, enhanced as part of capital improvement projects.
The county should promote voluntary wildlife habitat enhancement projects
by private individuals and businesses through educational and incentive
programs.
F. Soils and Organics
Soils play a critical role in the natural environment. Healthy soils keep disease-causing organisms
in check, recycle and store nutrients, and provide an important medium for air and water to pass
through. The properties of a healthy soil are similar to those of a sponge, faucet and filter. They
naturally regulate the flow of water, bind and degrade pollutants. The presence of millions of
macro and microorganisms in soil creates a "vibrant soil culture" where organic material is
consumed and air and water are retained. Nutrients are made available to plants to allow healthy
root growth and oxygen generation.
Human activity often causes soil compaction, removal and erosion of healthy, native soils. Fewer
organisms are present in disturbed soils. The resulting decrease in organic matter inhibits the
soil's ability to hold water, which increases surface water runoff. In addition, plants can not thrive
in disturbed soils because of the lack of nutrients. This, in turn, causes people to use more
chemical fertilizers, pesticides, and water to induce plant growth.
Increasing the organic content in disturbed soils can help restore their environmental function.
Composted organic materials that might be used include yard debris, food and wood wastes,
soiled paper, biosolids and/or livestock wastes, but not fly ash from industrial smokestacks.
Benefits of incorporating composted organic materials in soils include: improved stream habitat,
healthier plants, and closing the recycling loop for organic materials.
Organic soil content can be increased during the development process. Typically, in a new
development, topsoil is removed, and then later replaced. Developers can incorporate composted
organic materials during the construction process by replacing removed topsoil with organics in
areas to be landscaped to mitigate the impacts of development.
E-184
E-185
Conservation of native soils should be accomplished through various
mechanisms to ensure soils remain healthy and continue to function as a
natural sponge and filter, minimizing erosion and surface water runoff.
Native soils should be retained on site and reused on site to the maximum
extent possible.
Organic matter should be used in disturbed soils, such as those found in
developed areas, and shall be increased through various mechanisms.
Organics comprise a large portion of the waste generated by King County residences, businesses
and farms. This organic waste stream requires significant solid waste, farm management, and
wastewater treatment resources. Many of these "waste materials" (yard debris, food and wood
waste, soiled paper, biosolids, and agricultural livestock wastes), can be recycled and reused to
provide numerous uses that are beneficial to the environment and the economy.
4-23 September 2004
King County has a long history of resource conservation and waste recycling. Programs have
successfully captured organic materials for beneficial use such as yard debris, recycling and
biosolids applications to farms, forests and composting. However, large volumes of yard debris
and food scraps continue to be thrown away in the landfill. Significant volumes of livestock waste
generated in the suburbs and rural areas are inadequately managed, which can adversely impact
water quality and fish habitat.
Although efforts are underway to increase the amount of organic materials that are recycled, the
region still lacks the capacity to process all of these materials. Along with its efforts to promote
beneficial use of these products, King County is working with organic material processors and
others to try and increase the processing capacity in the region. The challenge will be for King
County to secure funding sources to ensure that sufficient processing capacity is in place to
handle a variety of organic waste materials.
E-186
E-187
E-188
King County should implement programs to improve availability and markets
for organic materials for soils that have been disturbed by new and existing
developments.
King County shall regard the region's organic waste materials as resources
which should be reused as much as possible, and minimize the disposal of
such materials.
King County shall identify long-term options for expanding the organic waste
material processing capacity in the county.
King County seeks to divert as much material as possible from disposal to reduce overall costs of
solid waste management, conserve resources, protect the environment, and strengthen the
county's economy (see Chapter 7, Facilities and Utilities, Policy F-255). In many cases, organic
materials can be recycled into a beneficial, highly valued resource helping to meet these diversion
goals. Beneficial uses of organic materials include, but are not limited to, the following:
King County recognizes that in most cases, the best management method for yard debris and
livestock wastes is to compost it on the property where it is generated. Examples of residential
onsite yard debris management techniques include grasscycling (leaving the grass on the lawn
when it is cut) and backyard composting.
E-189
E-190
King County shall promote and encourage the beneficial use of organic
materials, including but not limited to their use in the following activities:
agriculture and silviculture; road, park and other public project development;
site development and new construction; restoration and remediation of
disturbed soils; nursery and sod production; and landscaping. Organic
materials do not include fly ash.
King County agencies shall use recycled organic products, such as compost,
whenever feasible.
Biosolids are the nutrient rich organic product from the wastewater treatment process which can
be recycled as a soil amendment. At King County's wastewater treatment plant, solids are
removed from the wastewater and treated in large digesters where the organic solids are
stabilized, reducing the volume by half. After digestion, a portion of water is removed, leaving the
semisolid material ready for recycling.
The Biosolids Management Program emphasizes beneficial use of the resource and pursues
environmental stewardship through diverse public-private partnerships. One hundred percent of
county biosolids are beneficially used through the forestry and agriculture programs. A portion of
the biosolids are composted as a Class A product.
September 2004 4·24
E-191 King County should explore ways to beneficially use biosolids, whenever
feasible, locally.
Supporting agriculture is a key growth management strategy and vital to quality of life for King
County residents (see Chapter 3: "Rural Legacy and Natural Resources Lands"). However,
improper livestock management practices can have significant adverse impact on surface water,
ground water and air quality.
On-farm composting as a method of managing livestock waste and other organic waste materials
is becoming an important waste management strategy for farmers. Benefits of on-farm
composting include:
• Additional revenue from the sale of compost;
• Reduced costs for water, fertilizers and pesticides, due to reduced water usage and reduced
reliance on fertilizers and pesticides;
• Reduced impacts to surface waters; and
• Increased crop yields.
King County has approximately 200 commercial farms and 10,000 noncommercial farms in cities
as well as unincorporated areas. King County's Livestock Management Ordinance, Ordinance
11168 adopted in December 1 993, requires livestock owners to manage livestock waste so that it
minimizes any impacts to streams. The Livestock Management Ordinance requires the
preparation of farm plans to be developed jointly by farmers and the King Conservation District to
assist in reducing water pollution from their operations. The conservation district provides
technical assistance and education to agricultural landowners on how to implement best
management practices for federal, state and local water quality regulations. These best
management practices include slurry tanks and manure lagoons, the installation of fencing to
keep stock from streams and wetlands, and development of plans for livestock manure storage
facilities in accordance with the Sensitive Areas Ordinance.
E-192 King County shall develop alternatives to improve onsite and offsite
management of livestock wastes and recommend strategies to integrate
processing livestock wastes with other organic waste materials. These
strategies should be consistent with the King County Comprehensive Solid
Waste Management Plan, including but not limited to on-farm composting
and land application of processed yard debris. Alternative strategies for
onsite and offsite management of livestock wastes shall be based on farm
management plans, which protect water quality in streams and wetlands.
Solid waste management and water quality programs should be developed to
prevent liquid farm wastes from contaminating our watersheds.
4·25 September 2004
11._ Endangeretl Species Act
In March 1999, The National Marine Fisheries Service (NMFS) listed the chinook salmon as
"threatened" under the Endangered Species Act (ESA). In December 1999, the U.S. Fish and
Wildlife Service (USFWS) listed the Puget Sound and Coastal Bull trout as threatened under the
ESA. It is anticipated that listing of other salmon id species may follow in the near future.
The listing of a species under the act is cause for great concern, because Wild Pacific salmon
have great environmental, cultural, economic, recreational and symbolic importance to the Puget
Sound region. It is King County's goal to ensure long-term protection of our salmon resources to
harvestable levels for today and tomorrow, with the least economic impact possible. Successful
restoration and maintenance of healthy salmon populations will require time, money and effort,
and collaboration with federal, state, tribal and local governments, as well as businesses,
environmental groups, and citizens.
In accordance with the ESA, National Oceanic Atmospheric Administration (NOAA) Fisheries
issued regulations deemed necessary to provide for the conservation of Puget Sound chinook
salmon and other West Coast salmonids. This rule, commonly referred to as a 4(d) rule, legally
establishes the protective measures that are necessary and advisable to provide for conservation
of a listed species. The rule also makes it a violation of the ESA for any person, government, or
other entity to "take" a threatened species. ''Take" under the ESA includes altering habitat of a
listed species such that it causes harm.
Local governments in the Puget Sound region, in cooperation with state and tribal governments
and other major stakeholders, established the Tri-County salmon conservation coalition to identify
early actions and develop long-term conservation strategies. The early actions focus on
protecting salmon habitat in order to preserve options for recovery. The long-term conservation
strategy is being developed at the Watershed Resource Inventory Area (WRIA) level. The
boundaries of WRIAs are defined under state regulations, and generally adhere to the watershed
boundaries of major river or lake systems. King County is participating in the development Water
Resource Inventory Area plans for WRIA 8 (Cedar/Sammamish Watershed), WRIA 9 (the
Green/Duwamish Watershed), WRIA 7 (the Snohomish/Snoqualmie Watershed), about half of
which is in King County, and WRIA 10 (the White/Puyallup Watershed), a small percentage of
which is in King County.
E-201 King County shall continue to participate in the Water Resource Inventory
Area planning efforts and in other regional planning efforts, such as the Tri-
County salmon conservation coalition and Shared Strategy for Puget Sound,
to develop plans for each of the watersheds in King County. These plans
shall:
September 2004
a. Focus on early federally listed salmon id species first, take an ecosystem
approach to management and seek to address management needs for
other species over time;
b. Identify early actions and long-term projects and programs that will lead
to information on habitat conditions in King County that can enable the
recovery of endangered or threatened salmonids, while maintaining the
economic vitality and strength of the region;
c. Address both King County's growth management needs and
conservation needs;
d. Be comprehensive and based on best available science as defined in
WAC 365-195-905 through 365-195-925;
4-26
E-202
E-203
E-204
E-205
•
e. Address water quality, water quantity and channel characteristics;
f. Be developed in coordination with key decision-makers and
stakeholders; and
g. Provide for monitoring and adaptive management.
King County has evaluated and will continue to evaluate programs and
regulations to determine their effectiveness in contributing to ESA listed
species conservation and recovery, and will update and enhance programs
and plans where needed including evaluation of the zoning code, the Critical
Areas Code, the Shoreline Master Program, the Clearing and Grading Code,
the landscaping Code, the Surface Water Design Manual, the flood hazard
reduction plan, regional wastewater services plan,_best management
practices for vegetation management and use of insecticides, herbicides and
fungicides, and best management practices for agricultural lands and forest
lands under county authority. King County may amend these regulations,
plans and best management practices to enhance their effectiveness in
protecting and restoring salmonid habitat, using a variety of resources
including best available science as defined in WAC 365-195-905 through 365·
195-925 and resource documents developed by the Tri-County salmon
conservation coalition and the shared strategy.
Through the Watershed Resource Inventory Area planning process,
geographic areas vital to the conservation and recovery of listed salmon id
species shall be identified. King County will evaluate this information to
determine appropriate short and long-term strategies, including, but not
limited to: designation of Fish and Wildlife Habitat Conservation Areas,
development regulations (special district overlays, zoning, etc.) acquisitions,
facility maintenance programs, and capital improvement projects.
King County may use its authority under the Growth Management Act,
including its authority to designate and protect critical areas, such as fish
and wildlife habitat conservation areas, to preserve and protect critical
habitat listed for salmonid species by developing and implementing
development regulations and nonregulatory programs.
King County shall, in cooperation with the cities, ensure a no net Joss of
housing capacity that preserves the ability to accommodate the 2022 growth
targets, while pursuing compliance with Endangered Species Act
requirements. To achieve this goal, densities shall be increased on buildable
lands, consistent with Policy U-463.
4·27 September 2004
-~
(
\---'.--
')
I
I
/)
I
I
I
l
\
(
I
I /
~J /
\
\
\
I / ()
I
I
I
~P ...
V,
C
<>. I ..
) Par!\
I
)
4
.,,,.
\ ./
' /'., _,,:-_: i / . -r ·-... . .._ ___ .-r;.-~~ ~-<l~·· er;-Way ·-,.,'\ . -~i;: ·-~
) . ".-.
~
_: )
,, C
King County Com preh ensive Plan, 2004
Chapter Four, Environment
m.\Jon~101ects\ccrfl)lan\2004\'2::,04 wi!d\te h1'b mxd
""
AW C \\dd11117071:J IS·m\maps\2C0412\l<CCPl.awc_20C4 1229_2004 _w ·~lt a _hab pdt
~.
-. . ... ~·-'--~-. -----------·--·-·--------
)....,·..-0
/
!
,t:::. ,,
.. I ,.
.,.,../""
,)
'· ·' .
/
.. ~/l' ~-
. ~...,._~ . -f i p-
l t,e information 1nciuded on Uus map h as been comp,oo by
Kin!l County stafl from a v ar iety ot 101.m:1Bs ;1n d 1s subjoct 10 d ·1~~
witho u, nolic~ Kin;;i County m.1k1Bs n o representations or
wasr ant iu, exp,ess or imp'~d . as to occ uracy, c o"1)!ete nen,
timeliMS5, 01 righ1s to the use of s u::h inl omu.llQl'I King County
sh;:oil not be liablo fOf an y gtt1Hnal ~ial ind .iect, 1nc1dental . or
consoquont~I darna[ilils rlClud:ng, but not li/'Med M, lcsl
re11FJm:u or !os1. pmlrt! resutt1l'lg lrom ttie use or misuse cl l he
U1101mal 10n coolained on this map Any s,1lo c l t'1is ma p 01
iribrma.11on on th is map is prohibited e •ce~f by wr~ten permission cl
Kir g C ounty
The maps Jn the King County Comprehensive Plan and rrs technical appendices are produced wdh a computer geographic
information system. They are reduced in s;ze but avaHable at a target scale.
Wildlife Habitat Network
and Public Ownership 2004
c=J City-Owned or Managed Land
-King County Open Space System Lands
;::: __ J State Pa rk s and State-Owned Land
-Federally-Owned Land
[ ... _ 1 Incorporated Area s
[_ __ 1 Tribal Lands
~ Wildlife Network
'' .. ,, Alpine Lakes Wilderness Boundary
Source: U.S. Forest Service, King County Depa rtmen ts of Assessments , Natural Resou rces and Parks,
and Developmen t and Environmenta l Serv~es
Nole: Public Ownership within incorporated areas and County-0,med Land other than parks
are no r displayed
(® King C:Ounty
u 6 --------~---
10 -~ ..
N +
Octobe r 2004
Cha ter Five
Parks, Open Space
and Cultural Resources
Cha ter Five
Parks, Open Space and cu1.1ura1 Resources
The quality of life in King County is directly linked to the quality of our region's environment, with
its diverse landscapes reaching from Puget Sound to the Cascade Mountains, scenic beauty and
the variety of cultural and recreational opportunities that enrich our lives. These vital natural and
cultural resources contribute to the physical, mental and emotional well-being of county residents
and are integral to attracting employment and business activity.
The policies in this chapter focus on the county's role as a regional leader in acquiring and
protecting its system of county-owned parks and other open spaces and in supporting cultural
opportunities such as music, theater, ethnic heritage museums, literary activities, public art
collections, urban historic districts and rural landmarks.
5-1 September 2004
I. Parks, Becreatian and Open Space
The Growth Management Act states that counties are the providers of regional services and local
rural services, while cities are the appropriate providers of local urban services. As the regional
government, King County manages a regional open space system of parks, trails, natural or
ecological areas and working resource lands. While the cities are the managers of local park, trails
and open space lands in the Urban Growth Area, King County will continue to be the provider of local
park, trails and open space lands in the Rural Area.
Population growth and associated development in recent years have transformed the county's
landscape as forested and open lands have been converted to urban uses resulting in the
fragmentation of wildlife corridors, riparian habitat and the depletion of working resource lands and
open vistas. The policies in this section provide guidance for the open space system of lands the
county owns and manages to protect the health of natural systems, provide recreational
opportunities, shape community character, and help sustain agriculture and forestry economics. The
policies also reinforce the county's focus on linking components of the open space system.
Regional active and multiuse parks serve a countywide population and provide high-quality, highly
developed facilities to support multiple events, large group gatherings and special events. Local
rural park sites provide for active and passive recreation close to home. Local trails provide
recreation, circulation within the local community and access to the regional trail system.
Natural areas and some parks contain undeveloped or undevelopable acreage that remain in a
natural or near natural state and support habitat and other ecologically significant attributes.
Together these sites enhance environmental and visual quality and meet regional and local rural
recreation needs.
P-101 For the purposes of the King County Open Space system, "Regional Parks"
shall mean sites and facilities that are large in size, have unique features or
characteristics and serve communities from many jurisdictions, and "local"
shall mean sites and facilities that predominantly serve communities in the
unincorporated area.
A. The Regional Open Space System of Parks, Trails, Natural Areas and
Working Resource Lands
The policies in this chapter provide t.he basis to develop a contiguous open space system,
connecting and including active and passive parks, trails, natural areas and working agricultural
and forest resource lands. The Open Space System map shows these publicly-owned open
space lands and provides the basis for identifying the linkages necessary to strengthen the
physical and functional connectivity of the county's open system. The following policies reinforce
the importance of the county's open space system, and guide planning and management of
appropriate recreational opportunities that best meet regional and local needs, preserve
ecologically significant resources and protect working resource lands. Implementation of these
policies is guided by the King County Park, Recreation and Open Space Plan, adopted in 1996
(and subsequent updates).
P-102 King County shall be a regional leader in the provision of a regional open
space system of parks, trails, natural areas, working resource lands, and
flood hazard reduction lands. The regional network of open spaces provides
September 2004 5-2
benefits to all county residents including: recreation facilities, conservation
of natural and working resource lands, flood hazard protection and related
programs, and services. Preservation will include wildlife corridors and
riparian habitat, as well as open space areas separating urban and rural
areas.
B. Local Parks
In the Rural Area, the large geographic area and dispersed populations, individual lots, low
residential density and economies of site management dictate fewer individual park sites. Nearby
regional parks and other open spaces also provide recreational opportunities. King County's role
in the Rural Area will reflect rural levels of service.
P-103 Local parks, trails and other open spaces that complement the regional
system should be provided in each community, in Rural Areas, to enhance
environmental and visual quality and meet local recreation needs. King
County shall provide local parks, trails and other open spaces in the Rural
Area.
P-104 King County should provide local parks within rural communities with fields
and other facilities that provide opportunities for active sports. These
facilities shall be in addition to and compatible with King County's regional
park system.
C. Components of the Regional Open Space System
King County's regional open space system contains lands with many functions including active
and passive recreation, special purpose sites such as pools and trails; natural areas, including
waterways, greenways, and forested areas with educational, scientific, wildlife habitat, cultural or
scenic values; working resource lands including agriculture and forest lands; and community-
defining systems, including physical and or visual buffers between areas of urban and rural
development. Many sites within the open space system serve more than one function, but each
site serves a primary role within the system.
1. Active Recreation, Multiuse Sites and Trails
King County's local and regional parks and facilities accommodate a wide range of active and
passive recreation activities. Active recreation includes a functional system of highly developed
sites with_organized, scheduled activities such as soccer and softball. Passive recreation includes
activities such as informal play, hiking, walking, jogging and picnicking. Multiuse sites can include
a combination of active recreation and passive recreation with less intensely developed facilities
and natural areas. The Trail System is a major element of the recreation and natural systems and
provides recreation and non motorized transportation, as well as corridors often used by wildlife.
Regional programs serve a broad spectrum of users. These programs include those not generally
viable for individual communities due to site or facility requirements or the unique nature of the
offering requiring a broader user base to support them. Educational or interpretive programming
promotes appropriate and enjoyable use of the park system. Public awareness of resources and
their values builds support and stewardship for the system and its resources.
P-105 King County shall provide regional parks and recreational facilities that serve
users from many neighborhoods and communities. Regional parks include
unique sites and facilities that should be equitably distributed.
5-3 September 2004
P-106 King County shall complete a regional trails system, linking trail corridors to
form a countywide network. King County will continue to primarily own the
land necessary for the operation and management of the trail.
P-107 King County should facilitate educational, interpretive and aquatic programs
on county-owned properties that further the enjoyment, understanding and
appreciation of the natural, cultural and recreational resources of the park
system and the region.
P-108 King County should facilitate and seek regional and national programs and
special events at regional sites and facilities.
2. Natural Areas (Ecological Sites)
The King County Open Space system includes many sites whose primary purpose is to conserve
and restore ecological value. These sites may allow public use that does not harm the ecological
resources of the site. These natural areas include many environmental features of King County's
landscape, which play a role in protecting a diversity of vegetation and fish and wildlife important to
the beauty and character of the region. King County will focus on linking natural areas to create
regional open space corridors of greenways and waterways along the major river systems,
shorelines, and the Mountains-to-Sound Greenway.
Preserving these areas in partnership with other agencies, private groups and individuals will provide
multiple values including environmental and economic benefits of surface water management,
aquifer recharge, and fish and wildlife habitat preservation and enhancement.
P-109
P-110
King County will manage its natural areas to protect, preserve and enhance
important natural resource habitat, biological diversity, and the ecological
integrity of natural systems.
King County shall recognize and protect the natural character and ecological
value of its natural areas. These areas are important for preserving fish and
wildlife and their habitat, native vegetation, and features of scientific and
educational value. Development and public use may be limited to preserve
the natural state and reduce disturbance of the natural resources. Site
improvements should be focused on providing educational and interpretive
opportunities. Public access should be directed to the less fragile portions of
a site to ensure continued protection of the ecological resources.
3. Working Resource Lands
The county's open space system includes lands that are managed as working farms and forests.
The county has purchased several properties with the intention of conserving the resource use on
the site. County ownership and management of these lands conserves the resource land base,
allowing the resource activity to continue, while contributing to the local rural economy, providing
education about agriculture and forestry, and providing passive recreational opportunities on
some properties. The county's policies to conserve farmland and encourage agriculture are
discussed in Chapter 3.
The Farmland Preservation Program (FPP) is a county program that preserves farmland through
the purchase of development rights. The farms in the FPP generally remain in private ownership.
The county has purchased a farm outright in few cases, with the intention of reselling the land
without the development rights to a private farmer. The county has developed a program to lease
farms to small-scale farmers until such time that the property can be resold.
September 2004 5-4
P-111
P-112
P-113
Farmland owned by King County shall contribute to the preservation of
contiguous tracts of agriculture land and make affordable farmland available
for use by small-scale and new farmers.
Farmers leasing properties owned by King County shall use Agricultural best
management practices, Integrated Pest Management and other sustainable
farming methods.
The use and management of farmlands owned by King County shall be
consistent with any requirements imposed by the funding program used to
purchase each property and shall serve to meet and enhance the objectives
of the King County Agriculture Program.
One element of the King County Forestry Program is the conservation of forestland through
acquisition to allow forest management on the property. The working forests owned by King
County are generally very large parcels of land (several hundred acres or more), which support
sustainable forest management practices and contribute to the retention of a contiguous forest.
These properties contribute to environmental protection, high-quality passive recreation, the public
understanding of forestry, and scenic vistas.
P-114 Forest land owned by King County shall provide large tracts of forested
property in the Rural Forest Focus Areas and the Forest Production District
(FPD) that will remain in active forestry, protect areas from development or
provide a buffer between commercial forestland and adjacent residential
development.
P-115 Forest land owned by King County shall be used to sustain and enhance
environmental benefits, demonstrate progressive forest management and
research, and provide revenue for the management of the working forest
lands.
P-116 Forest land owned by King County shall provide a balance between
sustainable timber production, conservation and restoration of resources,
and appropriate public use.
4. Other Open Spaces
Preservation of open space in the county is grander than the county system. Large areas of the
county are owned and managed by federal agencies, the state, and other local jurisdictions that
manage the land for environmental protection, resource production, or a wide range of recreation
opportunities. Additionally, open space benefits are often provided by private land owners
managing their land in ways that protect the environment, conserve natural resources, or provide
open vistas. King County acquires for other reasons, such as flood hazards or providing needed
public facilities. These lands can also contribute to open space conservation efforts.
King County has acquired lands and manages facilities along major river and stream systems for
the primary purpose of flood plain management and flood hazard protection. Major streams and
rivers are vital components of the county's open space system, therefore the flood hazard
reduction lands function as critical links in the county's open space network. King County will
continue to maintain flood hazard reduction land and facilities within available funding levels. The
county will also seek innovative measures for maintaining and improving flood protection,
reducing maintenance costs, integrating flood protection and recreational opportunities, and
achieving wildlife habitat protection and salmon recovery.
5.5 September 2004
D. Achieving the Open Space System
Parks and other county-owned open space lands ensure a quality of life today and a legacy to
generations of tomorrow. In King County, many types of open spaces and fish and wildlife habitat
remain in private ownership end may be subject to future development. To ensure that these
lands and resources are protected and to offer an alternative to acquisition, the county offers
landowners a wide variety of tools to preserve their property. Policies outlining strategies for using
these tools can be found in chapters 3, 4, and 7.
Cooperation, coordination and partnerships with public agencies, private groups and individuals are
necessary to develop the regional parks and open space system, to meet existing needs for park
and recreation facilities and to accommodate the needs of growth. The Mountains-to-Sound
Greenway, along the 1-90 corridor, is a successful model for coordination of efforts by public and
private entities to protect the backbone of the county's open space system.
King County will achieve the multiple benefits of resource protection and recreation by building
partnerships and coordinating with providers and user groups of the parks and open space system.
Working together, stewardship can be fostered and these lands and facilities can be enhanced,
restored and operated more economically and efficiently to benefit all county residents.
P-117 King County shall explore incentives, regulations and funding mechanisms to
preserve, acquire and manage valuable park and open space lands.
P-118 Parks, trails and other open space lands should be acquired and developed
to meet adopted standards with a combination of public funds and
dedications or contributions from residential and commercial development,
based on their service impacts.
P-119 Open space sites should be acquired when identified in the King County
Park, Recreation, and Open Space Plan, adopted in 1996 (and subsequent
updates), or when needed to meet adopted local park and recreation
standard, or to protect contiguous tracts of working resource lands or
ecological resources.
P-120 Trails should be acquired when identified in the King County Trails Plan or
when identified as part of a community trail network.
P-121 King County shall be a leader in establishing partnerships with cities,
adjacent counties, federally recognized tribes, state and federal agencies,
school and special purpose districts, community organizations, nonprofit
organizations, land owners and other citizens. The county and these
partnerships should work to promote and protect all aspects of
environmental quality and complete the regional parks and open space
system, linking local and regional lands and facilities.
P-122 Decisions on acquisition and development of park, trail, and other open
space sites should consider funding needs for long term maintenance and
operations.
P-123 Open space lands shall be classified to identify the primary role in the open
space system and purpose of acquisition as active recreation, trails,
multi use, natural area or working resource lands. They will be classified as
regional or local and the primary role and purpose of the site will be
identified.
September 2004 5-6
P-124
P-125
P-126
P-127
P-128
P-129
P-130
Lands preserved for public parks or open space should provide multiple
benefits whenever possible.
A variety of measures should be used to preserve and develop regional and
local parks, trails and open space. Measures can include: county funding,
partnerships, incentives, regulations, and trades of lands and shared
development activities. Where local park districts have been created, King
County will work in partnership with the districts to maximize resources and
meet community goals.
King County will adopt an entrepreneurial approach to managing and
operating the open space system and work aggressively to implement
multiple and appropriate strategies to sustain fiscally the open space system.
Management of the regional open space system of Parks, Trails, Natural
Areas and Working Resource Lands is guided by the King County Parks,
Recreation and Open Space Plan, as adopted in 1996 (and subsequent
updates). The plan includes policies on the management of parks and trails,
natural areas, and resource lands.
King County shall use park and recreation standards as adopted in the King
County Park, Recreation and Open Space Plan, adopted in 1996 (and
subsequent updates), as guidelines to evaluate and provide local parks,
trails, and recreational services.
In the Urban Area, King County shall work in partnership with other
jurisdictions to facilitate annexation and transfer of local parks, trails and
other open spaces to cities or other providers to ensure continued service to
the community.
King County should work with cities to share operational and maintenance
costs of parks and other open spaces in unincorporated areas in which a
substantial portion of the users are from incorporated areas.
5.7 September 2004
1,1. Cultural Resources
Cultural resources make a significant contribution to the quality of life in King County. Arts and
heritage organizations, public art and historic and archaeological properties contribute to the region's
economic vitality, play an essential role in cultural tourism, and contribute significantly to the county's
overall quality of life. As King County grows, the need to protect, support and enhance cultural
opportunities and resources is essential in order to sustain livability.
King County continues to play an important role in support and guidance for cultural resources in
the region. While the creation of the CDA places operational responsibility for cultural resources
with that body, the King County Council approves nominations for membership on the Authority
Board, participates directly through board membership of three county council members; meets
with the CDA board to receive annual reports on progress and discuss plans for the coming year,
and similar functions.
In the following policies and discussion, the term "cultural resources" refers to all performing and
visual arts events, programs and facilities: public are; heritage events; programs and facilities; and
historic properties. The term "historic properties" means all historic buildings, sites, objects, districts,
and landscapes, prehistoric and historic archaeological resources, and traditional cultural places.
P-201
P-202
King County shall protect cultural resources and promote expanded cultural
opportunities for residents to enhance the region's quality of life and
economic vitality.
King County shall support the transmission of the region's cultural legacy,
promote cultural education, and encourage the preservation and celebration
of cultural diversity and creativity.
County residents need arts and heritage opportunities that balance regional programs and facilities
for attendance with a network of local community opportunities for participation and education. The
regional cultural system is comprised of a regional and local infrastructure of cultural organizations,
individuals and venues; an interjurisdictional program for historic resource protection; and region-
wide enhancement of public places with art works.
P-203 King County shall support and encourage development of regional cultural
organizations, facilities, and services that address a countywide audience or
are dedicated to unique and significant cultural themes or disciplines.
P-204 King County shall support and encourage community cultural organizations,
facilities, and services to provide opportunities for local access and
participation by all residents throughout the county.
A. Arts
The region's artistic environment parallels its natural features in variety and richness. Its arts
organizations, artists and opportunities are widely known and valued for their diversity, excellence
and abundance of music, theater, dance, literary activity, and visual arts.
September 2004 5-8
P-205 King County shall support excellence and vitality in the arts and support
opportunities for attendance at and participation in diverse arts and cultural
activities throughout the county.
P-206 The Cultural Development Authority of King County or its successor
organization_shall advise the King County Executive and the Council on
programs, policies and regulations that support and increase access to the
arts.
8. Historic Preservation
Preservation of historic properties provides multiple benefits to the region; historic properties
maintain a tangible connection with the historic and prehistoric past. They contribute character,
diversity and aesthetic value to communities, particularly in times of rapid change. Historic
attractions play a significant role in the region's appeal to tourists. Many municipalities do not have
sufficient resources to administer an historic preservation program. As a result, the shared history of
the region is endangered. Comprehensive and coordinated protection of significant historic
properties is necessary in order to ensure that King County's collective history is preserved.
P-207 King County shall administer a regional historic preservation program to
identify, evaluate, protect and enhance, historic properties.
P-208 The Landmarks Commission shall advise the King County Executive and the
Council on programs, policies and regulations that support and enhance
preservation and protection of significant historic properties.
C. Public Art
Collectively, public art is a regional resource that enhances community character and diversity,
sparks imagination, and provides a direct cultural experience for county residents every day. For
new or changing communities, public art is a powerful contributor to local character, sense of place
and belonging. Public art can also help mitigate the adverse effects of new development.
P-209 King County shall provide art in public facilities projects and places to
enhance community character and quality of life. Maintenance and
conservation shall be a consideration in the development and management
of public art. King County undertakings (including public-private
partnerships and development authorities) that include public funds or
resources, have publicly visible physical components, or require mitigation
should include public art. King County should encourage provision of public
art in private development projects.
P-210 The Cultural Development Authority of King County or its successor
organization_shall advise the King County Executive and the Council on
programs, policies and regulations that support and increase access to
public art.
D. Heritage
Museums, historical societies, ethnic organizations and other heritage groups, and historians,
archivists, folklorists and other heritage specialists enrich community life and provide cultural
experiences for county residents and visitors. Without appreciation, preservation and stewardship
of local history by heritage specialists, groups and organizations, the county's rich history would be
lost.
5-9 September 2004
P-211 The Cultural Development Authority of King County or its successor
organization shall advise the King County Executive and the Council on
programs and policies that support and enrich King County's heritage.
P-212 King County shall support, preserve and enhance its heritage and shall
encourage opportunities for public attendance and participation in diverse
heritage activities throughout the county.
E. Cooperation
Cultural resource management crosses jurisdictional boundaries and involves countless public and
private players throughout the region. The range and complexity of cultural activity in the region
requires coordination and cooperation. King County government is uniquely able to provide regional
coordination and leadership.
P-213
P-214
King County shall pursue its cultural resource goals by working with
residents, property owners, cultural organizations, public agencies, federally
recognized tribes, schools and school districts, and others.
King County shall work with cities to protect and enhance historic resources
and public art located within city boundaries and annexation areas. The
county shall advocate for and actively market its historic preservation
services to agencies and cities that could benefit from such services.
Cultural facilities and services are needed in locations and ways that expand public access, broaden
diversity of content and audiences and enhance cultural opportunities for all residents.
P-215 King County shall encourage shared, multipurpose use of regional and
community facilities for cultural activities to maximize their efficient use and
to expand public access to cultural opportunities.
F. Stewardship of Cultural Resources
Historic preservation is an ongoing activity that requires identification and evaluation of resources,
use of a variety of regulatory protection measures and incentives, and attention to long-term
preservation, enhancement and interpretation. Land use planning should direct and coordinate
patterns of development so as to minimize current and future conflicts with historic resources in
urban and rural areas.
P-216 King County shall encourage land uses and development that retain and
enhance significant historic properties and sustain historic community
character. County building and zoning codes and other regulations and
standards should provide flexibility to accommodate preservation and reuse
of historic properties. Zoning actions should take into account the effects of
zoning on historic properties.
Project review can respond to and modify development proposals affecting historic and
archaeological resources to eliminate or minimize adverse effects of development or changing land
use. King County government can also protect historic resources through careful planning and
review of its own undertakings, both direct and indirect. Archaeological resources are particularly
sensitive and endangered.
P-217 King County shall review public and private projects and may condition them
in order to protect historic properties. King County agencies shall coordinate
September 2004 5-1 o
P-218
P-219
with the Historic Preservation Program to provide consistent review and
mitigation for projects within unincorporated areas and for county
undertakings within cities.
King County shall inventory historic properties in order to guide decision
making in resource planning, capital projects, operations, environmental
review and resource management.
Archaeological properties shall be identified, evaluated and protected in a
consistent and coordinated manner. King County shall establish consistent
review and_protection procedures and develop centralized professional
archaeological staffing.
Cultural resources are often destroyed through neglect. Maintenance and other management
practices that protect historic features and character can assure long-term preservation.
Information about the history and significance of a property fosters appreciation and informs
owners, users and the public about its value.
King County government can lead by example through stewardship and wise management of its own
cultural resources. Historic public buildings and facilities, such as bridges and roads, can be
preserved and continue to be used; other historic resources can be converted to public use.
P-220
P-221
P-222
P-223
All King County agencies shall be stewards of cultural resources under their
direct control. Agencies shall identify and assess cultural resources,
preserve significant historic properties and public art, and provide public
access to them whenever appropriate. Agencies shall collaborate with the
Historic Preservation Program to nominate eligible properties for landmark
designation.
King County shall interpret its cultural resources to enhance their
understanding and enjoyment by the public.
King County shall acquire and preserve historic resources for use by county
and other public agencies and shall give priority to occupying historic
buildings_whenever feasible.
King County shall provide incentives to encourage investment in historic
properties and public art. County programs and incentives for land and
resource preservation and economic development shall support and be
coordinated with cultural resource preservation and provision of public art.
5·11 September 2004
I
I
I
) •
,Q ,..
,f>
~
V,
e
"
"-
"'
I '
\ ~'>------.. \~
King County Com pre hensive Plan , 2004
.., -----;:;~~-~--------. ------------------------------------------------·-·--·-·---·----·-·-------------~~-----------------------------·-:.._L,
' . ... . ~ t ~--·:" , ., ) . · .. , 1--. I
. • J , . ·· 2 I ' ,, I"' , .. -:--"91 ·-0 _/
---f . • ---.. T ~ lu·· -, ---, __ : '--... ,
' ; .I .,,. / -, . r ~ •· ·-"'
. t ' .... ,....... --,.-;-i---. < ,, •• ' I o
J • ( ' ' \ . ' ' I ' .. , . ,,
.;.···::_.,__ ~ I
, A> . ;. ,,,,., . . \
. . ' ,, "'"" ~" • , I
> -~-,-\· y /' ', ~ -:C,;-,·~ • ""----~ .• • ; '"' -;,,, . . ~ ( ' ,, , , J ,,.~,. .C.j;. , I' \ 1 -~ ~ ' _.) ' , "' ., ../"'-...J . , ' . ,; "~'-( . \.,__ -ffi ~ I
@) r---·--~, ---. J ~ T,"f ·,:w•_gf
o,;:>,1, J
. . . ~~ r '»I.... ,/
r ~ J ·. \ ,. ,,,. r
t\-'· ~ ~ . ·, ,.. ~ . ,·1· -{--\._ .
• : • ~ ·\-~ :;-.· . !
~~-.> l
,':\ . rO
.. ' ~-,. •'. .. ,... (•.;' . , I
11 • , --.., ., f @) ..... . / ;; ·''!lf'.J .,-,. . 1~-·,l: ' ·c .;; I. / -i: -:-,~.2.. ... --r , .
\ ('-:. -n ' ," ..i1 \ / -' i .@ Seh•-1[ .' .. \~::::--II ,----......_ _)
~rmaPdv i i_ i 1 ·. :r -,·" . 9 '-..,____ .. '· f
King County's
-,, . , J I J '· , CJ
Par!< I "\ _ . ./. ·:..... ·1 ;_ -.. •· ,'isl # '>"-) ,f
J r-· -3' . "-' \ .. ' \' t' I
\... 1 1'.t . ....._ "
.11', r-, . • ...____ _____ ...... I ~,,..,_. t ./ , . -.. r·"'
...... o,J < ,-; t-.: ''''"· ,,.,...,;" ,,1~·1111• ] -... j', -f\·frfll ---4
Open Space System 2004
/1. ij" ,1 ·· .,~ . .!. i I ~ ·
• .. -•• ~---.1_ -,~-. • -~ •• <',,
I . "· ~~.<,, ___ ....,.:. -;r ' ' ~,t
. 1 -· 167 ! . . . -r ' /
·---l~-fl -i ~: . .,. ~ (l F'\.~1>¥:;tl <!,,,, / -· ... -· -~ -...... ~ .• .,...~ ,s
., ...... ' ~ . '-i''t·"\ . (\_ -"' ' f" /,:. : : : . -·-....-J ........ _ . -~ \ -·-~-: ·:·~-". ) i
' . ... \ .. , ·,._
. · .. / ' J~;,1!) · ,m .. u , "~"'''~"' I I -~-~a._ ___ L...~--L----~~~ (~,<, l _..)
·1 1 --r =· ./
I. f ~ ---l
'? ·-----·, ' ·, \ --~ \.. . ---·--. \ ~ !
-I \.. • i , <. \._..,,-. "" c:tl /r"'--· , \
'---1 . ' -·'/ l . ....-...._. ) \ ····-"'°' ·"' 1'... --" . _ __, -;:T'-, ·,. ·---.._...., -~ --~ ~----/" ~
I -~f \ ~ I . _,-'--. ,,..-"·, _,.. '--.f .... --~
,. """"" I ' ""'-------/ ,_._~ Co,,ity \-, \
'\ >
-Recreation and Multi-Use Parks
-Reg ional Trai ls
-Natural Areas
rm -Working Resource Lands
Flood Hazard Properties
Other Public Lands
:---~j Incorporated Areas
~ Urban Growth Boundary
Source: King County Department of Nat..-at Resources and Parks
Water and Land Resou rces Division
(® King County
N
Chap ter five , Pr eseNl ng and Enriching our Communiti es
Tho irformation ncluoe<I on this map ha s beoo co~,l ed by
King County staff lrom a v ariety ol sou·ces ilnd is subject to c h,1nge
wilhout noti,;o Ki ng County makes no roprosentallon, or
warranfiea, expurn er ifr4:ilied. ~ to accuracy, corl'1=l11tene ss
timell"l,ess , o r ri<;hta l o l r',e lL';9 of auch information_ Kng Coonty
15,haJI net b,e liable for arry> gen,eral. special indr ,ect . 11'\C1dental. er
ccn9c.qyonti.ll dJmag es inciud.ng. but not limtcd 10, lost
rsvo nucs or I06t polits resuttin~ h orn tho U$e or misus-0 o1 the
inforrna,ion con1ained on '.h ,a map An 'f 1,11() ol this r-,ap or
information o n thi s map i s proh1bHd excep! by wn uen perrlU:tio,1 ol
"-..., ,..,..\. .......___ _ _..... __ ___,
0
l!!!!!li
2.~
lliiiiil!!II
19 ~' +
m·\tony',?'Ojec1s'll'.:ornplan\2004\200~_open_space.n-xd
A"NC \\ddes701'19~-m\map3\200412'2004_KCCP\awc_2004 1222_open_wace .pdl
The maps in the King County Coo,p,ehensive Plan and its technical apper,d,ces are produced with a com~re, geographic
lnformatiOn system. They are r educed ;n size t:Jut a vaHa ble at a larger scale Octo ber 2004
Chapter Six
Transportatio,n
Chapter Six
Transportation
This chapter is based on the land use element as established in this plan. King County envisions
a future transportation system that supports the regional land use strategy, which seeks to focus
most growth in urbanized areas. King County's goals are to:
• Connect all modes of transportation to form an integrated, balanced system;
• Strengthen the region's economy by moving people and goods efficiently;
• Give individuals and families a range of affordable transportation options; and
• Minimize transportation's adverse effects on the environment.
This chapter is consistent with and meets the requirements of regional and countywide plans and
policies that respond to growth management legislation. The Countywide Planning Policies (CPP)
have been used to guide the development of the transportation element and to ensure
consistency with plans and programs developed by adjacent jurisdictions.
Regional direction for the transportation element is set by the Metropolitan Transportation Plan,
Destination_2030 developed by the Puget Sound Regional Council (PSRC). The Metropolitan
Transportation Plan is consistent with the region's urban growth strategy, Vision 2020, also
developed by the PSRC.
The framework and direction for the development of comprehensive plans is provided by growth
management legislation. The transportation element of the King County Comprehensive Plan is
consistent with and meets the requirements of growth management legislation.
Components of the Transportation Element
The Transportation Element of this plan is comprised of five major components. The first is the
Transportation chapter, which includes the narrative and policy language. The second is
Technical Appendix C of this Plan, which contains the Land Use and Travel Forecast Technical
Report, the Arterial Functional Classification Map, and a transportation inventory. The third
includes the Transportation Needs Report, which is adopted herein by reference and contains a
20-year financial forecast and a 20-year list of transportation needs, and the Roads Capital
Improvement Program, which is also adopted herein by reference. The fourth is the Long-Range
Transit Development Plan and the Six-Year Transit Development Plan and Capital Improvement
Program, which are also adopted herein by reference. The fifth and last component is the
concurrency regulation, which implements the concurrency requirements and is codified at King
County Code chapters 14.65 through 14.70.
6-1 September 2004
1. Regional svstem
A. Countywide Transportation Service Provider
King County provides countywide transit service and builds and maintains arterials of countywide
and regional significance within unincorporated King County. King County also provides contract
transportation services to a number of King County cities.
The Growth Management Act fundamentally changed the way King County carries out
comprehensive planning, placing special emphasis on transportation by making it unlawful to
approve development that fails to meet the test of concurrency. Future development is
constrained by King County's ability to finance needed transportation facilities or programs. To
limit sprawl, create the desired urban form, and provide some measure of predictability, King
County will support comprehensive plan policies by focusing resources in the most efficient and
cost effective way.
As a countywide transportation service provider, King County will maintain Metro Transit's public
transportation services and work with Sound Transit and other transit agencies to provide
seamless, multi modal transit services. King County will cooperate with other local governments
and the Washington State Department of Transportation to implement the Regional Arterial
Network, improve freight mobility and carry out strategies to maintain the efficiency of freeways
and arterials in the region.
In the unincorporated Urban Area, King County will complete the roadway network, add sidewalks,
bike lanes and transit facilities as appropriate, and maintain the transportation infrastructure to
allow denser development to occur. In the Rural Area, King County will emphasize maintenance
and safety rather than increased traffic capacity.
King County International Airport/Boeing Field (KCIA) is an essential element of the county and
region's multimodal transportation system. The airport is also a significant employment center
and supports over 150 aviation-related businesses including the Boeing Company. The airport is
a port-of-entry for international flights and serves regional air carriers, national and regional cargo
carriers, corporate aviation, and general aviation aircraft. KCIA is a regulated facility under
Federal Aviation Regulation Part 139 of the Federal Aviation Administration (FAA) Code of
Federal Regulation (CFR).
T-101 As a countywide transportation service provider, King County establishes
policy for transit and for the unincorporated area road system. General and
long-range policy shall be established for the road system in the King County
Comprehensive Plan and for transit in the Transit Long-Range Policy
Framework. The Six-Year Transit Development Plan and the six-year capital
improvement program for roads shall also be prepared consistent with these
primary policy documents.
T-102 In addition to involving the general public, transportation plans including any
update to the Roads Strategic Plan shall be completed with timely input from
the unincorporated area councils and the subarea transportation forums,
among other bodies.
T-103 King County should identify improvements and strategies needed to carry out
the land use vision and meet the level-of-service requirements for
transportation. Road improvements should be guided by the Roads Strategic
September 2004 6-2
•
Plan and prioritized in the Transportation Needs Report and Roads Capital
Improvement Program. Public transportation projects should be identified in
the improvement program of the Transit Capital Budget and the Six-Year
Transit Development Plan, and the Long-Range Policy Framework for Public
Transportation.
T-104 King County International Airport shall plan, design, and implement services,
programs, and facilities in compliance with Federal Aviation Administration
regulatory requirements to support a safe, secure, and efficient global
aerospace system.
T-105 King County should develop a long-range financial component that generally
evaluates and describes funding sources and strategies to carry out the
transportation element. An annual six-year financial plan should be prepared
that considers transportation priorities and is used in developing the Capital
Improvement Program.
B. Public Transportation
King County Metro Transit provides bus and van service, ridesharing, paratransit. employer
programs and other custom services in cities and unincorporated areas. One of King County's
missions is to increase transit ridership by providing the best possible public transportation
service, thereby improving regional mobility and the quality of life in King County. To achieve this
mission, King County works with other local governments and communities, including Sound
Transit, to provide an integrated network of public transportation services.
A major redesign of the King County Metro Transit system was successfully implemented
between 1996 and 1999. As a result, Metro Transit now offers more connections between
employment centers and suburban activity centers. New partnerships with employers have also
led to greater use of transit, carpools and vanpools to ease congestion during commute hours.
The Six-Year Transit Development Plan, 2002-2007, guides Metro Transit operations and capital
investments. The plan focuses on the development of public transit service and facilities
consistent with land use goals of this comprehensive plan, the Growth Management Act and the
King County Countywide Planning Polices. Important issues for the Six-Year Transit
Development Plan include: the coordination of transit and roadway improvements along arterials
that cross more than one jurisdiction to improve traffic flow throughout the county; the
coordination of regional transit services in the three-county area served by Sound Transit and its
partner transit systems; and the improvement of intermodal connections.
1. Regional Coordination
Bus, rail, and ferry transit services cross county boundaries, providing the critical transportation
links on which our regional economy depends. In addition, all of our transit services depend on
convenient connections to our roadway, highway, and nonmotorized systems.
As the region continues to grow, transit routes and schedules must be coordinated between
agencies and modes so transit will be a viable and convenient option for our citizens and visitors.
It is also imperative that King County seek input from a broad spectrum of county residents to
ensure that services meet citizen needs.
T-106 King County should work collaboratively with governments and communities
to implement a locally based, regionally linked network of public
transportation services and facilities addressing regional, inter-community,
and local service needs. King County should actively develop, implement,
6-3 September 2004
T-107
and promote nonconventional public transportation options as a part of that
system.
Functional transportation plans should be coordinated with other related
transportation plans and programs of other jurisdictions and may include
coordinated funding arrangements to maximize the effectiveness of available
resources.
T-108 King County should work with the Washington State Department of
Transportation and Kitsap County to ensure that service and capital plans for
ferries are consistent with transit service plans and goals. King County
should encourage additional passenger-only ferry services to enhance the
county's multimodal transportation network for both commute and
recreational trips.
2. Transit Infrastructure
King County's transit infrastructure and service investments are developed to meet regional, inter-
community, and local travel needs throughout the county. The policy framework used to make
these investments must balance comprehensive plan requirements, regional cooperation, funding
constraints, and community needs.
T-109 In areas where transit services and ridership demand warrant, the county
should invest in transit supportive facilities consistent with the capital and
service strategies in the Six-Year Transit Development Plan.
3. Linking Transit and Land Use
To support transit ridership throughout the county, King County encourages land use policies that
link denser development with transit service. It costs more to provide transit service in low-
density, single-use communities. In denser, mixed-use communities like downtown Seattle,
Belltown, downtown Bellevue and Renton, transit routes have high ridership and recover a high
percentage of their operating costs, allowing for more frequent service. Transit-oriented
development (TOD) and transit centers in transit corridors can provide similar benefits.
T-110 King County and local cities should adopt transit supportive road design
standards, site access guidelines and land use regulations to promote transit
use, high-density development, mixed uses and reduced parking in the Urban
Growth Area. Site design should stress connectivity with adjacent
neighborhoods and other land uses via transit, pedestrian and other
nonmotorized facilities.
T-111 Transit centers and park-and-ride lots should include safe and convenient
access for buses, high-occupancy vehicles, pedestrians and bicycles to
minimize conflicts with other traffic. Mixed land uses should be encouraged
at transit centers and park-and-ride lots to meet passenger and commuter
needs and reduce vehicle trips. Park-and-ride facilities should be designed
with consideration of the most efficient use of land.
T-112 King County supports transit-oriented development in transit corridors. King
County shall encourage public/private partnerships to propose opportunities
for joint transit-oriented development. Such developments should provide
priority access for transit, pedestrians, bicyclists, car and van pools and
other alternatives to single-occupant vehicles.
September 2004 6-4
C. Regional and Freight Mobility
King County's transportation system relies heavily on freeways and arterials to move people and
goods. As federal and state highways become more congested, efficient operation of the regional
arterials has become more important. The management of this arterial system is now a central
part of King County's efforts to sustain the region's livability and economic health. King County
uses advanced information processing, communications, sensing, and control technologies to
facilitate management of the arterial system.
Freight mobility is critical to King County's economy and western Washington's role as a major
national and international trading region. King County should support efforts to plan and create a
fast, reliable freight transportation system in the region. To maintain the region's competitive
edge, our transportation infrastructure must provide for the efficient movement of goods and
freight to and from our port and industrial areas balanced with the needs of general purpose and
high occupancy vehicle traffic.
The freeway and arterial system that is most crucial to the movement of people and goods is
included in the Metropolitan Transportation System (MTS) and Regional Arterial Network (RAN).
The MTS is the system for the four-county region and is documented in PSRC's Destination 2030.
RAN is an integrated system of roadways that are critical for the movement of people and goods
in King County. The RAN approach encompasses growth management and capital investment
strategies for improved mobility between urban centers. Since many RAN corridors pass through
multiple jurisdictions, RAN stresses a regional, multimodal approach to coordinate improvements
such as transit enhancements, additional capacity, traffic signals timed for maximum mobility, and
high-occupancy-vehicle lanes for buses and carpools. Together the MTS and RAN comprise a
very important, high capacity system for moving people and goods.
T-113 King County shall be a regional proponent for freight planning and mobility
projects and actions that result in a reliable and efficient freight
transportation system. The county should identify opportunities to create
financial partnerships to achieve these goals.
T-114 King County should identify and develop major transportation projects,
including traffic operations and safety related projects, which improve freight
mobility. This work shall be coordinated with local jurisdictions, other
counties or regional agencies, the state, ports, and the private sector.
D. Transportation Demand Management
To sustain and enhance regional mobility, King County should be a leader in implementing
programs and land use measures that encourage people and businesses to reduce single
occupant vehicle trips. Transportation Demand Management (TOM) covers a broad range of
efforts to reduce single-occupant vehicle travel including telecommuting, congestion pricing,
parking management, nonmotorized travel, site design standards, public information, ridesharing,
public transportation, joint use of parking facilities, and park and ride and other intermodal transfer
facilities. Transportation demand management contributes to successful implementation of new
private and public development, concurrency, the regional arterial network, and other transit and
road investments such as High Occupancy Toll (HOT) lanes, High Occupancy Vehicle (HOV)
lanes, and Intelligent Traffic Systems (ITS).
T-115 Transportation Demand Management (TOM) strategies should be used to
promote travel efficiency and energy conservation and reduce the adverse
environmental impacts of the transportation system. These strategies should
include commute trip reduction, demand management and system
management. TDM measures may include telecommuting, congestion
pricing, parking management, nonmotorized travel, site design standards,
6-5 September 2004
public information, ridesharing, public transportation, joint use of parking
facilities, and park and ride and other intermodal transfer facilities.
T-116 Transportation demand and system management strategies beyond those
adopted as county regulation may be considered as one of a menu of
measures to mitigate for traffic impacts of proposed development.
Transportation demand and system management strategies, as well as other
mitigation requirements may be imposed on new development as mandatory
mitigation measures as necessary to meet the requirements for mitigation of
impacts pursuant to the State Environmental Policy Act and the State
Subdivision Act.
T-117 Management of employee parking, such as the provision of preferred parking
for high-occupancy vehicles and bicycle parking, should be used to support
alternatives to commuting by single-occupant vehicles. Employers should
consider the accessibility to adequate public transportation and high-
occupancy vehicle facilities and services when developing site ahd parking
plans.
T-118 King County should participate financially in efforts to implement
Transportation Demand Management strategies, including policies developed
through regional consensus and adopted by the county. To this end, the
county shall identify funds to implement transportation demand management
strategies, public education/information, research and planning.
T-119 King County should work with the Washington State Department of
Transportation, Puget Sound Regional Council, and cities to develop and
implement a regional policy on appropriate applications of transportation
pricing strategies that reflect the higher cost of peak hour automobile usage.
T-120 King County should work with the cities and other affected agencies to
develop a regional parking strategy. This strategy should be consistent with
regional and local transportation plans. King County should encourage
shared parking facilities in areas where high-density, mixed-use development
is planned and where walking is convenient for short trips. This strategy
should include establishing minimum and maximum parking ratios.
September 2004 6-6
II. linking Transportation Infrastructure and Services wilb Growth
A. Land Use
The transportation element is based on adopted targets for household and employment growth to
the year 2022. These growth targets have been developed with consensus of the cities and are
based on a countywide growth strategy that encourages growth in the urban areas where public
facilities exist or can be provided efficiently. The new demands for travel created by such growth
could be accommodated consistent with level-of-service standards, revenue forecasts and the
overall King County land use development strategy and vision.
The growth targets are the basis of the transportation element and consistent with land capacity
and density estimates used to calculate travel demand in the county. Travel demand was used to
project the needs for transportation system improvements. The population targets for each area
should be considered as minimum growth amounts that may be exceeded under unexpected
scenarios of growth and development. The expected growth in housing units includes
development proposals that are already in the permitting process and are termed pipeline
development.
King County's transportation system should improve the mobility of residents providing greater
access to housing, jobs, goods and services, shopping and recreation, all of which are
characteristic of a high quality of life. The transportation component of this plan establishes a vital
link between land use and the transportation facilities and services needed to support growth.
The land use vision established in this plan has been used to develop the transportation policies,
needs, financing, and strategies.
T-201
T-202
T-203
T-204
The transportation system should provide mobility choices for county
residents, visitors and businesses in support of Destination 2030, the
regional transportation strategy; Vision 2020, the region's urban growth
strategy; and the county's land use and development vision, goals and
policies.
Travel modes should be interconnected to form an integrated, coordinated and
balanced multi modal transportation system that serves the travel needs of the
county both effectively and efficiently.
In addition to encouraging transit, and nonmotorized mobility choices
including pedestrian and bicycle travel, the transportation system should
address the needs of persons with disabilities. King County should evaluate
and implement, when appropriate, innovative ways to address these needs in
the design and operation of transportation infrastructure, facilities, and
services.
The transportation system should include:
a. Freeways, arterial streets and local/neighborhood streets;
b. Local and express bus transit and paratransit services, including
Americans with Disabilities Act (ADA) service programs;
c. High-capacity transit;
d. High-occupancy-vehicle lanes and ridesharing facilities;
e. Demand and system management programs;
f. Facilities and programs for pedestrians, bicycles and equestrians;
6-7 September 2004
g. Facilities to accommodate freight and goods delivery, including railroads,
intermodal yards and distribution centers;
h. Airports; and
i. Marine transportation facilities and navigable waterways.
T-205 The transportation system in the Urban Growth Area should be consistent with
urban development policies and growth targets. System improvements should
implement the Urban Land Use Chapter and be prioritized according to the
capital and services strategies in the Six-Year Transit Development Plan and
the goals, strategies, and actions in the Roads Strategic Plan and should be
reflected in the Transportation Needs Report.
T-206 The transportation system in the Rural Area and Natural Resource Lands should
be consistent with their rural/resource character. Projects will be prioritized to
address safety, operations, and capacity improvements that correct existing
deficiencies or serve development that is already in the permitting process. All
projects should emphasize safety, maintenance, and environmental quality.
T-207 King County shall not construct and shall oppose the construction by other
agencies of any new arterials or freeways or any additional arterial or freeway
capacity in the Rural Area or Natural Resource Lands except for segments of
certain arterials that pass through rural lands to serve the needs of urban
areas. Any capacity increases to these urban connector arterials shall be
designed to serve mobility and safety needs of the urban population while
discouraging development in the surrounding Rural Area or Natural Resource
lands.
T-208 King County recognizes the impact to rural area mobility caused by urban
connector arterials that traverse the rural area, and should work with state
and federal agencies to mitigate these impacts when consistent with adopted
transportation policy.
B. Travel Forecasts
Travel forecasts provide one of the important steps in linking land use and transportation. The
land use vision and growth targets for planning areas have been allocated to the county's
transportation zone system. This provides the level of detail needed to develop travel forecasts to
analyze future transportation system performance and to identify system improvement needs.
Travel forecasts are based on the regionally adopted household and job growth targets for 2022
for the Urban and Rural Areas. The travel forecasting process is based on the Puget Sound
Regional Council's modeling and forecasting techniques.
T-209 The travel forecasts used to identify transportation improvements/needs
shall be prepared consistent with state law and on a schedule that coincides
with a major comprehensive plan update as outlined in King County Code.
C. Level of Service Standards
The Growth Management Act (GMA) requires level of service (LOS) standards for all arterials and
transit routes to judge performance of the transportation system. The GMA also calls for specific
actions and requirements for bringing into compliance facilities or services that are not meeting
the adopted LOS standard. King County's LOS standards comply with growth management
policies of encouraging growth in the urban area while restricting growth in the rural area.
September 2004 6-8
•
Level of service is a qualitative measure that describes traffic flow and is often represented by a
system using the letters A through F. Level of service A is the highest quality of service and level
of service F is the lowest. Level of service B is indicative of stable traffic flow. However, unlike
level of service A, operating speed is beginning to be restricted by other traffic. At level of service
E, operation is unstable, and speeds are reduced but will fluctuate widely from point to point.
There is little independence of speed selection and maneuverability at level of service E. Level of
service F is indicative of forced flow of traffic with extremely low speeds and long delays at
intersections.
King County uses two sets of measures to determine whether a proposed development meets the
LOS standards. They are an averaging of traffic congestion on roadways in the area and a
measure of traffic congestion in an individual corridor. Area wide averaging is used to judge
performance of the road system as measured against the adopted LOS standards. An individual
corridor measure is used to judge performance of monitored corridors as measured against the
adopted LOS standards.
T-210
T-211
T-212
T-213
The level of service (LOS) standard for the Urban Area and designated Rural
Towns shall be E except as provided in Policy T-209. The LOS standard for the
Rural Area shall be B except as provided in Policy T-209. These standards shall
be used in concurrency testing.
In Potential Annexation Areas where King County has a preannexation
agreement with the annexing city, the county will apply the annexing city's
adopted level of service (LOS) standard within that Potential Annexation
Area.
The LOS standard for certain minor residential and minor commercial
developments, along with certain public and educational facilities, shall be
LOS F. This standard shall be used in concurrency testing.
Level of service guidelines for allocating transit service should be developed
to be consistent with the Six-Year Transit Development Plan's policy
objectives. The land use criteria that are used to determine where future
transit service is allocated are established in the Six-Year Transit
Development Plan's service strategies. These Service Strategies provide the
framework for identifying the level of service that each community can plan
for as the Six-Year Transit Development Plan is implemented.
D. Concurrency
The Growth Management Act (GMA) requires local jurisdictions to adopt and enforce ordinances
that prohibit development approval if the development causes the level of service (LOS) on
identified county arterials or certain state roads to decline below the adopted LOS standards.
King County's Transportation Concurrency Management (TCM) program was developed to
address the GMA's concurrency requirement. The TCM program requires that transportation
facilities must be available to carry the traffic of a proposed development at county LOS
standards, or else the proposed development cannot be approved. The requirements of King
County's TCM program do not apply to transportation facilities designated by the Washington
State Department of Transportation (WSDOT) as "highways of statewide significance."
T-214 King County's transportation concurrency test shall be a two-part test,
involving area-wide averaging of roadway congestion and measuring of
congestion in specific roadway corridors.
6-9 September 2004
T-215 A Certificate of Transportation Concurrency confirms that adopted level of
service (LOS) standards are met by a proposed nonresidential development
or a residential concurrency zone. A certificate of transportation concurrency
will be issued only if a proposed development or residential concurrency
zone passes both parts of the two-part transportation concurrency test.
T-216 To ensure that adopted LOS standards are met, transportation improvements
needed to serve new development must be currently in place, or construction
for needed improvements must be funded in the adopted Six-Year Capital
Improvement Program.
E. Mode Split
"Mode split" means the share of total vehicle traffic by mode -bus, nonmotorized vehicle, carpool,
single occupant vehicle, etc. -during a particular time period. Mode split varies by time of day,
weekdays vs. weekend, and location. A higher mode split for non-single occupant vehicles,
usually during weekday peak periods, means fewer vehicles are needed to carry a given number
of people. Mode split is used as a measure of the efficiency of the transportation system.
Countywide Planning PolicyT-10 calls for local jurisdictions to develop mode split goals to
established employment centers. Unincorporated King County does not have any established
employment centers although cities within King County served by Metro Transit do. As part of the
Six-Year Transit Development Plan development, King County coordinates the establishment of
mode split goals for cities within the county.
The Metropolitan Transportation Plan provides policy guidance for determining mode split goals.
This chapter is based on the mode split policy guidance provided by that plan.
T-217 The county should pursue mode split goals through the implementation of
policies that support transportation demand management, transit service
improvements, and expansion of high-occupancy vehicle programs. The
county should recognize and support efforts locally, regionally, and
statewide to advance Transportation Demand Management technologies.
September 2004 6-10
111. Transportation svstem Planning and Design
A. Arterials and Streets
King County designs, builds, operates and maintains roads, bridges and pathways in
unincorporated areas of King County. The goal is to make the county's transportation system
safe and efficient for all uses and modes of travel. King County's arterial system represents a
broad range of mobility options. In the past, the arterial system has been characterized as the
system for moving cars and other vehicles. The arterial system should be viewed as a resource
for moving people and goods by many modes of transportation, including autos, carpools, buses,
bicycles, pedestrians, and trucks.
T-301
T-302
T-303
T-304
T-305
The most cost-effective improvement should be considered first to solve
existing and future deficiencies before higher-cost, capital-intensive projects
are considered. Efficiency improvements supporting high-occupancy-
vehicles (HOV) and transit operations on existing roads should be a higher
priority than general capacity improvements enhancing single-occupant-
vehicle (SOV) travel.
Transportation improvements should be designed, built, and operated to
minimize air, water and noise pollution and the disruption of natural surface
water drainage in compliance with provisions and requirements of applicable
federal, state and local environmental regulations. Natural and historic
resource protection should also be considered. Particular care should be
taken to minimize impacts where the location of such facilities could increase
the pressure for development in sensitive areas or rural or resource lands.
Needed rights-of-way, strategies to reduce demand and off-site
improvements should be identified and required as conditions of
development approval to the extent that such conditions are directly related
to impact mitigation and will benefit the development.
King County's road design and construction standards shall promote safe,
cost-effective roads that encourage multimodal use, reflect the different
needs and service levels for the Urban Growth Area and Rural Area,
responding lo the different needs for areawide mobility and access to
abutting properties.
Roadway safety improvements increase the safety of the traveling public by
reducing the number and severity of accidents, providing refuge for
pedestrians and bicyclists, providing positive traffic control, minimizing driver
decisions, reducing hazardous roadway conditions, and reducing unexpected
situations. Improvements of this type include, but are not limited to, pathways,
traffic signals, turn and merge lanes, provisions for sight lines, removal of
roadside obstacles, and improvements to lessen the likelihood and impacts of
localized flooding.
6-11 September 2004
T-306 Appropriate neighborhood traffic control measures, land use, zoning, design
and road standards and development conditions should be used to improve
safety, transit access and nonmotorized travel in residential neighborhoods.
T-307 King County should encourage the development of highly connective, grid-
based arterial and nonarterial road networks in new developments and areas
of in-fill development. To this end, the county should:
a. Make specific determinative findings to establish nonarterial grid system
routes needed for public and emergency access in in-fill developments at
the time of land-use permit review.
b. Encourage new commercial, multifamily, and single-family residential
developments to develop highly connective street networks to promote
better accessibility by all modes. The use of cul-de-sacs should be
discouraged, but where they are used, they should include pedestrian
pathways to connect with nearby streets.
T -308 Development proposals should extend the public road system through
dedication when the extension is in the public interest and is reasonably
necessary as a result of the impacts of the development. The impacts that
may warrant such an extension include, but are not limited to, impacts on
neighborhood circulation, increases in the use of arterials for local vehicular
. trips, the reductions in traffic safety through uncoordinated and/or
inadequately spaced street access to the arterials, and restrictions on the
availability of alternative emergency access routes.
T-309 The county should limit the placement of facilities or physical barriers and
improvements, such as buildings, utilities, and surface water management
facilities within specific areas of a development in order to allow for the
future construction of roads to facilitate the establishment of a safe and
efficient traffic circulation network, or to retain the availability of access to an
adjacent property.
T-310 As a condition of the approval of new development, the county should
require the improvement of existing offsite roadways and undeveloped road
rights-of-way, and/or other strategies to reduce demand on roads when the
improvement or strategy is reasonably necessary as a result of the impacts of
the development. The impacts that may warrant such improvements include,
but are not limited to, those that create safety concerns, raise road
operational issues or increase the number of residences served by a single
access route.
T-311 Arterial Functional Classification should be implemented through the King
County Road Design and Construction Standards. The comprehensive plan's
Urban Growth Area boundary should provide the distinction between urban
and rural arterials.
B. Public Transportation Strategies
King County's transit infrastructure and service investments are consistent with the capital and
services strategies in the Six-Year Transit Development Plan and balance policy requirements,
regional cooperation, funding constraints, and community needs.
T-312 King County should plan, design, and implement a system of services and
facilities that supports integration of regional and local services and that
September 2004 6-12
facilitates access to the system for pedestrian, bicyclists, transit
collection/distribution services, and persons with disabilities, thereby
providing a viable and interconnected network that is an alternative to auto
usage.
T-313 King County should support local and regional growth management plans
and policies. King County should work with other jurisdictions to focus new
and existing services and facilities to support targeted land use
concentrations identified in local comprehensive and regional plans and
within the Urban Growth Area of King County.
T-314 King County should adopt transit supportive policies assigning highest
priority to serving urban centers and manufacturing centers with transit
service, including transit priorities on arterial streets jointly designated for
transit priority by the county, cities, and the Washington State Department of
Transportation.
T-315 King County should use a community-based planning process when working
with cities and unincorporated area communities to develop effective transit
services including consideration of local circulation needs, feeder bus
service, fixed and nonfixed routes, and various coach sizes appropriate to
the neighborhood scale and market.
T-316 High-Capacity Transit facilities and services which are consistent with, and
supportive of, the comprehensive plan should be supported and
implemented.
C. Nonmotorized Transportation
The nonmotorized program is an essential element of King County's multimodal transportation
system. Nonmotorized transportation users include pedestrians, bicyclists and (in certain areas of
the county) equestrians. While each group has different needs, they all rely on King County's
road system for safe access. Trail networks, sidewalks, bike lanes, and other nonmotorized
improvements encourage walking and cycling. They also improve access to transit stops,
resulting in increased transit ridership and improving the quality of life in their communities.
T-317
T-318
T-319
Efforts should be made to improve non motorized transportation countywide
to increase safety, public health, mobility and convenience for nonmotorized
modes of travel. These efforts should emphasize the ability of non motorized
modes to extend the efficiency of regional transit, promote personal mobility
in a range of land use areas and expand the transportation alternatives
available to the public to form a complete or connected network.
King County should evaluate and implement, where appropriate,
nonmotorized transportation when general transportation improvements are
made, including road construction, reconstruction, subdivision development
and development of new transit systems.
New land use plans, subdivisions, and urban planned development proposals
should include enhancements to nonmotorized mobility and access to
surrounding areas.
6-13 September 2004
T-320 King County design standards should allow flexibility in selecting, and the
authority to require design features that benefit nonmotorized safety and
accessibility.
T-321 Unused rights-of-way should be considered for development as pedestrian,
bicycle, equestrian or accessible connectors.
T-322 King County should seek to improve pedestrian safety both within residential
areas and at arterials near pedestrian activity centers such as schools, retail
centers, concentrations of housing, transit facilities and trails. Within
residential areas, King County shall offer a comprehensive package of
neighborhood traffic services to unincorporated area residents and, on a
contract basis, to local jurisdictions. Pedestrian safety improvements should
include adequate signage, markings and signalization where warranted. To
foster safe walking conditions for students, King County should continue the
School Pathways Program.
D. Air Quality
The Washington State Clean Air Conformity Act establishes guidelines and directives for
implementing the federal Clean Air Act Amendments. The Washington Act specifically links air
quality conformity to growth management planning efforts at the local and regional level.
The Washington Administrative Code states that local transportation plans shall include," ...
policies and provisions that promote the reduction of criteria pollutants that exceed national
· ambient air quality standards." (WAC 173-420-080)
Global climate change continues to be a focus of local concern. It is clear that greenhouse gas
emissions from transportation sources are a significant contributing factor to global climate change.
Reducing greenhouse gas emissions from transportation sources is an important goal for King
County.
The following policies have been developed to be consistent with and support the policies in Chapter
4, Section 1 B of this Plan, "Air Quality and Forest/Tree Cover."
T-323 The transportation system should conform to the federal and state Clean Air
Acts by maintaining its conformity with the Metropolitan Transportation Plan of
the Puget Sound Regional Council and by following the requirements of
Chapter 173-420 of the Washington Administrative Code.
T-324 King County should work with the Puget Sound Regional Council, the State
Department of Transportation, transit agencies and other jurisdictions in the
development of Transportation Demand Management measures and other
transportation and air quality programs where warranted. This work would
address the requirements of the federal Clean Air Act as amended, the air
quality provisions of the federal Transportation Equity Act for the 21st Century
and the Washington State Clean Air Conformity Act and should include
measures to address greenhouse gas emissions.
T-325 King County should consider the following Transportation Demand
Management.strategies to reduce criteria pollutants and greenhouse gas
emissions_including, but not limited to: trip reduction strategies, transportation
pricing controls, employer transportation management programs, work
schedule changes, ridesharing programs, dedicated facilities for high-
September 2004 6-14
occupancy-vehicles, traffic flow improvements, parking management, bicycle
and pedestrian programs, mixed use development, and car sharing programs.
6-15 September 2004
IV. Fi.nance
King County's transportation vision depends on adequate funding for transportation needs. The
Growth Management Act requires that the county include an analysis of funding capabilities, a
multiyear financing plan based on needs and a discussion of how to raise additional funds or
reassess growth and level-of-service standards to resolve a potential funding shortfall for at least
a ten-year period. This section provides such information and discusses the extent to which the
transportation facilities can be funded within a reasonable revenue forecast and expenditure
schedule.
A. Funding Capabilities: Road-Related Sources
Financial viability to support transportation capital needs is tested at two levels. Initially, a 20-year
plan is identified to meet transportation improvements needed to support the plan vision. The 20-
year plan provides for an assessment of revenues from currently available resources and
identifies reasonable options for securing additional revenues over the life of the plan. Secondly,
the annual capital improvement program preparation provides a six-year window review that
examines the specifics of how to implement the financing plan.
King County receives road revenues from a variety of sources, including unincorporated King
County property tax, federal and state grants, state gas tax, local taxes and road mitigation
payments from private developments. A full description of transportation financing can be found
in the Roads Strategic Plan.
8. Revenue Shortfall
Comparing the plan's future transportation needs with projections of revenue from current sources
shows the total revenue shortfall over the 20-year planning horizon. Different strategies or actions
can be identified to address this shortfall. As an example, priority for funding may be given to only
projects directly related to achieving the level-of-service standard, to projects that are related to
providing capacity or to noncapacity projects.
The intent of this plan is not to demonstrate a dollar by dollar accounting of transportation needs
and revenues. Rather, it is to demonstrate the reasonableness of the plan and its implementation
and to show that the goals of growth management can be met. Other sections of this chapter
describe how the transportation element addresses growth management goals for transportation
and adequate facilities/services. The reasonableness of the plan's transportation element
focuses on the shortfall and the potential for funding future needs.
Strategies to address the shortfall can range from reconsideration of the transportation needs to
new revenue options to changes in levels-of-service to revisions of the land use policies.
Decisions on what to do should be made based on monitoring implementation of this plan. The
following actions can be used to balance the funding shortfall of the plan:
1. Reduce transportation funding needs:
• Reevaluate the need for projects;
• Promote transportation demand management actions to reduce vehicle trips; and
• Rescope project needs and downsize where possible.
2. Develop new revenue options:
• Increase revenues by using existing sources;
• Participate in regional funding strategy development;
September 2004 6-16
• Seek new or expanded revenue sources; and
• Public/private participation.
3. Change level-of-service:
• Adjust the level-of-service standard to allow more growth;
• Adjust the level-of-service standard to allow more growth in selected areas only; and
• Adjust the level-of-service standard to discourage more growth.
4. Change land use:
• Revise the land use plan to encourage/discourage growth in selective areas;
• Adjust the target forecast; and
• Delay development until facilities are adequate.
T-401 Financial resources available for transportation improvements should support
a program of capital facilities needed for a multimodal transportation system.
The Transportation Priority Process should give priority to critical capacity
projects needed to achieve level-of-service standards in the Urban Area.
T-402 The essential maintenance, preservation, safety and operations costs of the
transportation system should be funded prior to other costs for capital
improvements so that existing investment is protected and current mobility is
not degraded.
T-403 During annual review of the Comprehensive Plan, King County should consider
and address any potential shortfalls that may occur between expected
revenues and needed improvement costs. Such resolution could include a
reassessment of land use, growth targets, level-of-service standards and
revenue availability.
C. Urban Unincorporated Area Road Financing
Each area of urban unincorporated King County is unique in terms of its character, the issues that
its residents care most about, and its specific road-related needs. By targeting road capital funds
toward each area's most pressing needs, the county can provide the greatest overall benefit for
each public dollar spent. This prioritization process is particularly important since current funding
is inadequate to meet all needs and since road infrastructure is often an issue in annexation
discussions.
Road improvements essentially fall into three areas:
1. Operational and safety improvements such as signals, turn lanes, lighting, and crosswalks
improve system efficiency and safety. These improvements are needed throughout the urban
unincorporated area.
2. Urban retrofit improvements reconstruct existing street systems to current urban road
design standards (curb, gutter and sidewalk, enclosed drainage, and adequate surtace water
detention facilities) without adding more than a modest amount of additional capacity. Urban
retrofit improvements are especially needed in the West Hill and North Highline communities,
where most neighborhoods were developed before current urban road design standards were
established.
3. Capacity improvements build new roads or add two or more lanes to existing roads. These
projects generally are needed in areas with significant congestion or that have greater
potential for new development.
6·17 September 2004
Continuation of funding for transportation projects that alleviate existing deficiencies is a high
priority since all areas have existing capacity, operational, and safety deficiencies at one level or
another.
T-404 King County's urban road investments shall address the unique needs of each
unincorporated area and shall target the road deficiencies in each area that act
as barriers to infill, redevelopment, annexation, and the achievement of growth
targets.
T-405 Projects addressing existing capacity, operational, and safety deficiencies shall
have a high priority throughout the urban unincorporated area.
T-406 When funding transportation projects in areas where annexations or
incorporations are expected, the Department of Transportation should seek
interlocal agreements with the affected cities and other service providers to
provide opportunities for joint grant applications and cooperative funding of
improvements.
September 2004 6· 1 B
V. Coordination
This chapter has been prepared in coordination with adjacent cities and counties to assess potential
impacts on their jurisdictions. Citizen participation and coordination was also used to assist in the
planning process and to reconcile any conflicts. The following activities have supported the
coordination process:
• Review by the transportation subarea boards;
• Review by the Unincorporated Area Councils;
• Development of the Regional Arterial Network;
• The update of the Six-Year Transit Development Plan;
• The statewide and countywide grant application process:
• The Capital Improvement Program (CIP) coordination process: and
• Participation in the Puget Sound Regional Council, enabling King County to coordinate its
transportation planning activities with other local and regional agencies' for the four central Puget
Sound counties.
T-501
T-502
T-503
All elements of the transportation system should be planned and operated in
coordination with the cities in and abutting King County, the adjoining
counties, the Washington State Department of Transportation, the Port of
Seattle, the transit agencies that provide service in and to the County, and
the Puget Sound Regional Council. Prioritization of countywide facility
improvements should be coordinated among jurisdictions to implement the
countywide land use vision.
King County should work with the Puget Sound Regional Council and its
members to ensure that any regional projected aviation capacity problems,
and the air transportation needs of the region's residents and economy are
addressed in a timely manner.
King County should support the completion of the designated freeway HOV
lane and limited access highway system. Access to this HOV lane system
should also be supported.
6-19 September 2004
VI. 1mn1amao1a1ion a.nd Mo:nitorinu
The balance between land use, transportation services and funding is critical. The Transportation
Chapter will be implemented through the funding of planned transportation improvements and
strategies from available resources and by the management and monitoring of the system to ensure
there are adequate facilities to support growth. Roads needs will be prioritized through updates to
the Roads Strategic Plan and the Transportation Needs Report. High-priority projects will be
programmed for funding in the Capital Improvement Program. Transit projects will be implemented
as the needed revenues become available and in coordination with other related improvements and
service development needs as described in transit planning and budget documents.
The annual Capital Improvement Program and Financial Plan will be consistent with the
comprehensive plan and will consider the current performance of the transportation system,
concurrency needs of planned developments, priority projects, phased implementation of
improvements and other related factors. Revenues from all sources including Mitigation Payment
System fees will be programmed to appropriate projects.
Concurrency will be maintained through the development and use of the Transportation Concurrency
Management Program to help manage development and achievement of the level-of-service
standards adopted in the comprehensive plan.
System performance will be monitored through periodic traffic counts, speed and delay studies,
travel time observations for autos and buses and by computer simulation of travel network
characteristics. Information on system performance will be shared with other transportation
agencies in the county and with the_Washington State Department of Transportation. If performance
deteriorates below adopted standards, then the comprehensive plan will be amended to include
improvements needed to restore level-of-service standards, or a reassessment of standards, funding
and growth will be considered.
T-601 King County should maintain an inventory of its transportation facilities and
services to support its management of the system and to monitor system
performance.
T-602 King County shall periodically evaluate transportation components of the
comprehensive plan and shall recommend actions that ensure
implementation of the comprehensive plan vision.
T-603 King County shall monitor and establish benchmarks to assess regional
transportation system performance and implementation of the
comprehensive plan. To accomplish this task King County should develop
travel forecasts and maintain a Geographic Information System and
databases. The data shall include existing and forecast regional population,
employment, development and transportation information. The county, in
cooperation with other jurisdictions, should produce reports on traffic and
transportation activities. Such reports should highlight performance
characteristics and identify the deficiencies, problems of safety and
operations and areas not in compliance with level-of-service standards.
September 2004 6-20
VII_ Transportation Element:
Reauirements and Components
Specific requirements for the transportation element are found at RCW 36.70A.070(6)(a). The
following sections describe how the transportation element of the King County Comprehensive
Plan meets those requirements.
A. Land Use Assumptions
The transportation element uses the same growth targets as the entire comprehensive plan.
These targets are provided in Chapter Two of the Plan.
These regionally adopted growth targets have been used in developing the travel demand forecasts
for the comprehensive plan and in the development of the Transportation Needs Report. The Six-
Year Roads Capital Improvement Program is derived from the Transportation Needs Report. This
links the transportation plan with growth targets for households and employment.
B. Estimated Traffic Impacts to State-Owned Facilities
Both the King County Comprehensive Plan and the analysis conducted for the Transportation
Concurrency Management program include state facilities. Both use standard transportation
analysis techniques.
C. An Inventory of Transportation Facilities and Services
The inventory is provided in Appendix C. As required by growth management legislation, it includes
air, water, and ground transportation facilities and services as well as transit alignments and
general aviation airport facilities. It includes both county-owned and state-owned transportation
facilities within the county's boundaries.
D. Level of Service Standards Including Standards for State Routes
King County has adopted urban and rural area level of service standards for its Transportation
Concurrency Management Program. The standards consist of Transportation Adequacy Measure
(TAM) and Travel Time measures to determine if proposed nonresidential developments and
concurrency zones for proposed residential developments meet these standards. The TAM is
used to judge the performance of the county's road system. Travel time is used to judge the
performance of monitored corridors and critical road segments within the monitored corridors.
State routes, except for highways of statewide significance and state routes with HOV lanes, are
included in the TAM calculation. Portions of six state routes that are regionally significant state
highways are included in the county's list of monitored corridors
E. Actions to Bring Facilities into Compliance
King County's traffic impact analyses and other planning processes have identified needed
projects. These projects are listed in the Transportation Needs Report that is adopted by
reference along with the KCCP. The Roads Strategic Plan and the six-year Capital Improvement
Program identify specific projects, strategies, and actions to address transportation needs.
6-21 September 2004
F. Traffic Forecasts for at Least Ten Years
Travel forecasts were developed for the year 2022. See Section II and Appendix C for more
information on forecasts.
G. State and Local Transportation Needs to Meet Current and Future
Demands
King County will be in compliance with this new GMA requirement by the December 31, 2000,
deadline. The Transportation Needs Report six-year roads and transit development plans and
capital improvement programs are the elements of the King County Comprehensive Plan that
address the GMA requirement of identifying state and local system needs to meet current and
future demand.
H. Analysis of Funding Capability
A financial analysis is included in the Transportation Needs Report which is adopted as an
element of the plan. More information on the financial analysis is provided in Section IV of this
chapter of the KCCP.
I. Intergovernmental Coordination
See Section V for a discussion of coordination.
J. Concurrency
The concurrency program is described in Section II E of this plan.
K. Consistency of Plans
The comprehensive plan is consistent with the Metropolitan Transportation Plan, the regional
transportation plan for the four-county region. The Puget Sound Regional Council reviews the
plan for consistency and has previously certified the King County Comprehensive Plan and also
its amendments. In addition the comprehensive plan policies have been reviewed by other
jurisdictions within King County.
The comprehensive plan provides policy direction for the development of the county's 6-year
functional plans.
September 2004 6-22
Chapter Seven
Services. Facilities
and Util1t1es
Chapter Seven
Services, Facilities and Utilities
The Growth Management Act requires coordinated planning so that the services required by new
residents and their homes and businesses are available as growth occurs. Needed services
include many that are not provided by King County, such as water supply, local sanitary sewers,
fire protection, schools, energy facilities, and telecommunications. King County does provide
services such as regional wastewater treatment, regional solid waste management, and local
stormwater management. This chapter contains policies that guide service provision.
7-1 September 2004
I. R.egional Services
King County government is a regional and local service provider. Types of regional services
provided include transit, wastewater treatment, and solid waste management. Local services
provided to citizens of unincorporated urban King County and the rural areas include police,
building permits, and health and human services. As annexations and incorporations of
unincorporated urban areas continue, King County government will focus more on its role as the
provider of regional services and protector of the County's rural and resource areas. The
following policies direct King County's evolving role as regional service provider.
F-101
F-102
F-103
King County, the cities, special purpose districts and/or local service
providers shall plan as partners. King County's planning will focus on
unclaimed urban unincorporated areas and cities' Potential Annexation
Areas.
King County shall work with cities, special purpose districts, other local
service providers and citizens to identify and distinguish local and
countywide services. Over time, cities will assume primary responsibility for
coordinating the provision of local services delivery. The county will assume
primary responsibility for coordinating the provision of countywide services,
including countywide services that must be delivered within city boundaries.
The county will also work with cities, special purpose districts, and other
counties to identify regional service and facility needs and develop strategies
to provide them.
King County will provide or manage countywide services which include but
are not limited to:
a. Transit;
b. Economic development;
c. Harborview Hospital;
d. Public health;
e. Regional park, trails and open space systems;
f. Waste water collection and treatment;
g. Solid waste management and recycling;
h. Hazardous waste management;
i. Water resource management;
j. Surface water management;
k. Flood warning and floodplain management;
I. Protection and preservation of natural resource lands;
m. Regional Arterial Network (RAN) and freight mobility; and
n. Affordable housing.
F-104 King County will, in cooperation with special purpose districts and/or local
service providers, continue to plan for and provide public services to the
Rural Area, consistent with rural standards and needs.
F-105 To support the intent of the Growth Management Act, King County should
work with cities and other service providers to establish priority areas for
public funding of capital facilities, services and infrastructure.
September 2004 7-2
II. Facilities and Services
A. Providing a Spectrum of Services
King County and numerous service providers need to coordinate planning and funding activities
to ensure that needed facilities and services are provided in the region.
F-201 All facilities and services should be provided in compliance with provisions
and requirements ·of the Endangered Species Act.
F-202 King County should seek to create quality communities by defining the
needs and proposing strategies for a full range of public facilities and
services, including physical infrastructure and health, human and public
safety services. King County should ensure that there is an adequate supply
of public facilities necessary to support communities.
F-203 King County should work with the cities, special purpose districts and other
service providers to define regional and local services and to determine the
appropriate providers of those services.
F-204 King County shall work with its neighboring counties, the stale, Puget Sound
Regional Council, special purpose districts, ports and the cities to identify
areas of shared need and adequate land supply for public facilities. The
county's capital acquisition budget shall reflect the jointly agreed-upon
priorities and time schedule.
F-205 Public and private community service providers should be encouraged to
share or reuse facilities when appropriate, to reduce costs, conserve land and
provide convenience and amenity for the public. Joint siting and shared use
of facilities should be encouraged for schools, community centers, health
facilities, cultural facilities, libraries, swimming pools and other social and
recreational facilities.
B. Urban and Rural Services
Although growth will be directed to Urban Areas, it is recognized that Rural Areas have facility
and service needs also.
F-206 Public spending to support growth should be directed to the Urban Growth
Area and prioritized and coordinated through Capital Facility Plans to comply
with the concurrency requirements of the Growth Management Act.
F-207 In the Rural Area, services provided by agencies should support a rural level
of development and not facilitate urbanization.
C. Identifying Needs for Facilities and Services
Public facilities and services are vital to protect public health, safety and welfare and to protect
and enhance community and environmental quality. Inadequate sewage disposal, for example,
could directly threaten public health. Inadequate groundwater protection could result in unsafe
7-3 September 2004
drinking water and threaten stream flow. Deficiencies in other services, such as police protection
or parks, might not raise severe obstacles to any single new development, but over time could
cause general threats to public health, safety and welfare and deterioration of community quality.
King County government is responsible for assuring that adequate facilities and services are
available or can be made available to support planned growth. This responsibility is carried out by
identifying needs for facilities and services based on the planned amount and location of growth.
The mechanism for identifying needs is capital improvement programming.
The Growth Management Act requires the county to prepare a capital facility plan which includes
an inventory of existing capital facilities owned by public entities, a forecast of the future needs for
capital facilities, including the proposed locations and capacities of expanded or new facilities,
and a six-year plan that will finance the expanded or new facilities.
The Capital Facility Plan Element for King County is comprised of the following four components:
1. Technical Appendix A is an executive summary of documents containing inventories of
facilities and services provided by King County (health and human services and law, safety
and justice, transportation) and those provided by other entities (drinking water supply,
sanitary sewer collection and treatment, schools, fire protection, libraries, natural gas,
telecommunications, and electricity).
2. Technical Appendix A is an executive summary of documents containing the forecast of
future needs for capital facilities, including the proposed locations and capacities of expanded
or new facilities:
3. Six-year plan that will finance the expanded or new facilities:
a. Technical Appendix A is an executive summary of the finance plans for facilities and
services provided by the county and other entities.
b. Technical Appendix A references the Transportation Needs Report which includes an
analysis of funding capability to judge needs against probable funding resources, and a
20-year financial forecast report based on identified needs.
c. Current adopted King County Capital Improvement Program for facilities other than
transportation.
4. Requirement to reassess land use if funding is unavailable to meet existing and future needs:
a. Policies of Chapter Seven, Part I Facilities & Services, Sections B -F.
b. Chapter Nine, Transportation, Section IV.
D. Capital Facility Planning
King County and other service providers are required to prepare six-year capital facility plans that
describe needs for the six-year facility and propose funding to meet those needs.
F-208 The capital facility plans and capital improvement programs prepared by all
other agencies which provide services to unincorporated areas of the county
should be consistent with the King County Comprehensive Plan.
F-209 To reduce overall public costs, noise and disruption to the local area during
construction, installation of new or maintenance of existing utility facilities
should be timed and coordinated with other projects that utilize public right-
of-ways and easements, where possible.
F-21 O King County's capital facility plans should identify financing strategies to
support its adopted 20-year growth target and land use plan.
F-211 King County's capital improvement program shall demonstrate that projected
needs for facilities and services can be met within the Urban Growth Area
and can be served in compliance with the concurrency requirements of the
Growth Management Act or, if that is not possible, King County shall
September 2004 7-4
determine where and when deficits may occur and how needed facilities and
services might be phased in and or financed to serve such deficit areas.
Alternative phasing and financing strategies must be identified and
determined to be infeasible prior to triggering a land use and zoning
reassessment under Policy F-216.
F-212 School districts which choose to have the county collect impact fees for
them, and water and sewer utilities that provide their services to
unincorporated King County shall prepare capital facility plans consistent
with requirements of the Growth Management Act and King County Code.
F-213 Provision of an adequate supply of kindergarten through twelfth grade (K-12)
public schools and K-12 public school facilities is essential to avoid
overcrowding and to enhance the educational opportunities for our children.
King County shall adopt regulations which are supportive of the permitting of
K-12 public schools and K-12 facilities.
E. Addressing Service Deficiencies
In the event that needed facilities and services are not available to support either existing
development or growth, King County will work with other service providers to address the service
deficiency.
F-214 King County shall initiate a subarea planning process with any service
provider that declares, through their capital facilities plan, an inability to
accommodate projected service needs inside their service area.
F-215 King County and its cities should coordinate planning for health and human
service facilities and services. County investments in health and human
service facilities should be targeted primarily to the designated Urban
Centers and secondarily to other locations in the Urban Growth Area and
Rural Towns.
F-216 If an area-wide sewer, water, or transportation service deficiency is identified,
King County and the applicable service providers shall remedy the deficiency
through a joint planning process addressing capital improvement programs
and long-term funding strategies. If financing and level of service remedies
cannot solve the deficiency, King County shall change zoning to address the
problem.
F. Financing Strategies
King County, cities, and other service providers will work together to address the financing needs
of facilities and services.
F-217
F-218
King County shall work with the cities to create a financing partnership for
areas of the Urban Growth Area that the cities will annex. This includes
determining county/regional and city/municipal facilities and services and
then committing to a shared financing strategy to build or provide these
infrastructure improvements or services.
King County should, in cooperation with other jurisdictions, develop funding
strategies for governmental infrastructure that take into account economic
development goals and consider the costs to, and benefits for, the
jurisdictions and the region.
7-5 September 2004
G. Essential Public Facilities
The region will work cooperatively to site essential public facilities in an equitable manner.
Essential public facilities are defined in the Growth Management Act and include large, usually
difficult to site facilities such as prisons, solid waste facilities, and airports.
F-219 Proposed new or expansions to existing essential public facilities should be
sited consistent with the King County Comprehensive Plan. Listed existing
essential public facilities should be preserved and maintained until
alternatives or replacements for such facilities can be provided.
F-220 King County and neighboring counties, if advantageous to both, should
share essential public facilities to increase efficiency of operation. Efficiency
of operation should take into account the overall value of the essential public
facility to the region and the county and the extent to which, if properly
mitigated, expansion of an existing essential public facility located in the
county might be more economical and environmentally sound.
F-221 King County should strive to site essential public facilities equitably so that
no racial, cultural, or socio-economic group is unduly impacted by essential
public facility siting or expansion decisions. No single community should
absorb an inequitable share of these facilities and their impacts. Siting
should consider environmental equity and environmental, economic,
technical and service area factors. The net impact of siting new essential
public facilities should be weighted against the net impact of expansion of
existing essential public facilities, with appropriate buffering and mitigation.
Essential public facilities that directly serve the public beyond their general
vicinity shall be discouraged from locating in the Rural Area.
F-222 A facility shall be determined to be an essential public facility if it has one or
more of the following characteristics:
a. The facility meets the Growth Management Act definition of an essential
public facility;
b. The facility is on a state, county or local community list of essential
public facilities;
c. The facility serves a significant portion of the county or metropolitan
region or is part of a countywide service system; or
d. The facility is the sole existing facility in the county for providing that
essential public service.
F-223 Siting analysis for proposed new or expansions to existing essential public
facilities shall consist of the following:
a. An inventory of similar existing essential public facilities in King County
and neighboring counties, including their locations and capacities;
b. A forecast of the future needs for the essential public facility;
c. An analysis of the potential social and economic impacts and benefits to
jurisdictions receiving or surrounding the facilities;
d. An analysis of the proposal's consistency with policies F-219 through F-
222;
e. An analysis of alternatives to the facility, including decentralization,
conservation, demand management and other strategies;
f. An analysis of economic and environmental impacts, including
mitigation, of any existing essential public facility, as well as of any new
site(s) under consideration as an alternative to expansion of an existing
facility;
September 2004 7-6
g. Extensive public involvement; and
h. Consideration of any applicable prior review conducted by a public
agency, local government, or citizen's group.
F-224 King County supports coordination of regional water supply planning, sales
of excess water supplies among municipalities in the region, water quality
programs and water conservation and reuse programs.
H. Water Supply
King County is not a water utility and does not provide potable water to citizens in the region.
However, it plays an important role in the coordination or linking of water supply and growth.
Moreover, the county reclaims water from its wastewater treatment plants. Reclaimed water can
be used for many purposes, such as irrigation and industrial use, which currently utilize potable
water sources.
Reclaimed water produced by King County must be consistent with the standards contained in
the Washington Department of Ecology's "Orange Book," as promulgated under chapter 90.46
RCW. The "Orange Book" describes differing levels of treatment that are required to produce
different classes of reclaimed water. King County currently produces only Class A reclaimed
water, which is produced using the highest levels of treatment.
1. Potable Water Systems
Potable water is provided by Group A public water systems having 15 or more connections,
Group B public water systems having 2 to 14 connections, and individual private wells serving
one connection. Exempt wells refer to wells that do not require obtaining a water right from the
state for withdrawal of water. These exempt wells are subject to all other rules and regulations
other than the requirement to get a permit from the state to withdraw water. Water withdrawn
from an exempt well for individual or group domestic water supply cannot exceed 5,000 gallons
per day, nor may the water be used to irrigate more than a half acre of lawn or noncommercial
garden. The type of water system required for new development will depend upon whether a
proposed development is or is not located within the Urban Growth Area, is or is not within an
approved service area of an existing public water system, and is or is not able to provide an
adequate water supply as required under RCW 19.27.097 and/or RCW 58.17.110.
F-225
F-226
F-227
Group A water systems shall be responsible for fulfilling their duty to provide
service within their service areas approved under state law. The service
areas for Group A public water systems are defined by Coordinated Water
System Plans approved under chapter 70.116 RCW or by individual water
system plans reviewed by the county and approved by the state.
In the Urban Growth Area all new construction and all new subdivisions shall
be served by Group A public water systems except in the circumstance when
no Group A public water system can provide service in a timely and
reasonable manner per RCW 70.116.060 or when no existing system is willing
and able to provide safe and reliable potable water with reasonable economy
and efficiency per RCW 19.27.097.
In the Urban Growth Area, individual private wells are not permitted unless
application of Policy F-226 to a proposal for a single-family residence on an
individual lot would deny all reasonable use of the property. In that case, the
well would be allowed only as an interim facility until service by a public
water system can be provided. The individual well must meet the criteria of
the King County Board of Health Title 13.
7.7 September 2004
F-228
F-229
F-230
In the Urban Growth Area, if a Group A water provider cannot provide direct
service to new development in a timely and reasonable manner as required
under RCW 70.116.060 or chapter 43.20 RCW, a new public water system may
be established if it is owned and operated by the following, in order of
preference:
a. By the Group A system, in whose service area the system is located,
via satellite management, or
b. By a satellite management agency approved by the State Department of
Health under contract with the Group A system in whose service area
the system is located, provided that the existing Group A water system
remains responsible for meeting the duty to serve the new system
under RCW 43.20.260.
All new public water systems formed in the UGA shall connect to the Group
A water system in whose service area the new system is located when direct
service becomes available. All known and projected costs for anticipated
connection shall be funded at the permitting stage of any proposed new
construction or new subdivisions.
In the Rural Area, individual private wells, Group B water systems, and Group
A water systems are all allowed. Creation of a new public water system or
the expansion of an existing Group B system may be allowed to serve new
construction or new subdivisions when no Group A public water system can
provide service in a_timely and reasonable manner per RCW 70.116.060, or
when an existing system is not willing and able to provide safe and reliable
potable water with reasonable economy and efficiency per RCW 19.27 .097.
New public water systems established in the Rural Area shall be owned and
operated by the following, in order of preference:
a. By the Group A public water system in whose service area the system is
located, by direct service or satellite management by the Group A
system,
b. By a satellite management agency approved by the State Department of
Health and providing service within the county and under contract with
the Group A system if it is located in a Group A system service area; or
c. By the owners of the lots that are provided water by the new system if the
new system is not within the service area of an existing Group A system
or not within the area covered by a satellite management agency.
Approval for any such system shall be conditioned for future ownership
or management by a satellite management agency, when such service
becomes available, and for periodic review of system operations, as
required by RCW 70.119A.060(2).
Ecology has determined that the rivers and streams in the major river basins in King County have
no water available for further consumptive appropriation without harmfully impacting instream
values. For that reason, it has by regulation closed those basins to issuance of new water rights,
and has directed that the natural interrelationships between surface and ground waters should be
considered in future water allocation decisions in order to avoid adverse impacts to instream
flows. The installation and use of wells that are exempt from ecology's water rights permitting
process may further harm those rivers and streams when the wells are withdrawing ground water
that is directly connected to the water in the stream. The installation of new exempt wells may
also create health and safety problems by interfering with the water supplied by existing wells,
and by creating more holes in the ground that can lead to contamination of entire aquifers. Under
K.C.C. chapter 9.14, the Department of Natural Resources and Parks is to act as lead agency in
coordinating the activities of ODES and Public Health in order to ensure that groundwater quality
September 2004 7-8
and quantity are protected, and facilitate implementation of the plans that have been developed to
protect ground water in five groundwater management areas within King County.
F-231 New subdivisions with more than six single-family lots on Vashon-Maury
Island and in closed basins in the Rural Area (as defined in WAC 173-507,
508, 509, 510, and 515) may not be served by a potable water system using
an exempt well, or a combination of multiple exempt wells. One exempt well
per subdivision will be permitted unless more than one exempt well is ·
needed to meet the water flow requirements for the six residences. New
developments in the Rural Area served by an exempt well, or wells shall not
exceed one-half acre of irrigation.
F-232 King County shall work with the State Department of Ecology and the State
Department of Health to ensure that existing provisions of state law that
provide for measuring water withdrawals or diversions for sources of supply
are fully utilized to meet public health, resource protection, land use,
planning and fish recovery objectives and obligations. Any new or
expanding Group 8 water system shall have a totalizing source meter and
shall make information from the meter available upon request of King
County.
2. Regional Water Supply Planning
Over the past several years King County has been working cooperatively with many of the larger
water utilities in the region to gather information about regional water demand and supply. King
County would like to use this information to help develop a regional water supply plan.
F-233
F-234
F-235
King County supports development of a regional water supply plan for the
entire region. Key components of this planning process should include:
a. Involvement, oversight and support of elected officials in the region;
b. Meaningful public participation including the involvement of the state and
federally recognized tribes;
c. Prioritization of future supplies, including a role for conservation and
reclaimed water;
d. Assigned accountability for implementing conservation and developing
new supplies and infrastructure such as transmission pipelines; and
e. Legislative changes, if necessary, to implement the plan.
King County should assure that a regional water supply plan for all of King
County is prepared in cooperation with water utilities and in coordination
with affected federally recognized tribal, local and state governments. A
continuous and meaningful public process should be used to develop the
regional water supply plan, resulting in a plan that is adopted by elected
public officials in the region and used by the state in making water resource
decisions. The regional water supply plan should implement and be
consistent with growth management decisions made by local and regional
jurisdictions under the Growth Management Act and the approved water
quality and quantity strategies adopted by the region in compliance with
federal requirements under the Endangered Species Act, Clean Water Act,
and other authorities relevant to water quantity and quality.
The county will work with water utilities to develop a water supply plan that
prioritizes an array of potential sources, including conservation and
reclaimed water, and defines a publicly-and state-accepted strategy for how
the region could best meet future demands for water. During development of
the regional water supply plan, the county will work in concert with water
7-9 September 2004
utilities to evaluate the projected water demands for population growth and
other out of stream needs identified under the Growth Management Act,
Endangered Species Act response provisions in plans developed under the
state's Salmon Recovery Act, and Clean Water Act requirements for water
quality.
3. Utility System lnterties
Water utilities obtain water supplies from many varying sources. Some water utilities receive the
vast majority of their water supply from wells. Yet others receive substantial portions from
municipal watersheds and reservoirs. The varying water supply sources can differ substantially in
terms of dependability of output, so that while one water utility may have excess capacity, a
neighboring water utility could be experiencing severe shortages and be unable to adequately
serve their customers.
F-236 King County supports interties that allow the transfer of water resources
among water utilities in urban areas to meet the projected demands for
growth. The transfer of water must be consistent with locally adopted growth
management plans, regional water supply plans, groundwater plans,
watershed plans, and approved Coordinated Water System Plans, and
implement approved Endangered Species Act response requirements and
Clean Water Act requirements.
F-237 King County supports the development of appropriate regional water intertie
capital projects, subject to approval from appropriate local, state, and federal
agencies and consistent with Policy F-236.
4. Water Reuse, Conservation and Accounting
King County residents depend on proper management of water resources to ensure adequate
and reliable water supplies, and protection and preservation of natural resources. As a regional
service provider, King County plays a role, along with others, in managing these water resources
for long-term sustainable supply and protecting the long-term functions and values of natural
water systems. As part of its responsibilities, King County reviews water utility plans for those
utilities serving unincorporated King County and encourages the inclusion of elements related to
water reuse and conservation in the plans. The King County Code directs county programs to
specifically act as a clearinghouse for data related to groundwater quality and quantity in order to
facilitate implementation by King County and others of the groundwater management plans that
have been developed for major portions of King County.
F-238
F-239
King County's water reuse program and projects, as well as water reuse and
water supply/resources, should be coordinated with a regional water supply
plan in accordance with state and federal standards and coordinated with
comprehensive land use plans.
King County shall partner with utilities to publicize water conservation and
encourage best management practices that conserve potable water supply
through measures that include use of alternative supplies such as reclaimed
water. In exercising its role in reviewing utility water system plans, King
County Utilities Technical Review Committee (UTRC) shall encourage water
purveyors to include aggressive conservation and reuse measures where
applicable, as well as development of new sources to support planned land
uses with reliable service at minimum cost. Efforts to encourage the use of
reclaimed water shall focus on existing and proposed source supplies for
large water users, such as golf courses and cemeteries.
September 2004 7-10
F-240
F-241
In its review of water comprehensive plans, the King County Utilities
Technical Review Committee shall consider the following:
a. Consistency with land use plans and development regulations adopted
under the Growth Management Act;
b. Approved or adopted regional water resource plans, including basin
plans, groundwater plans, watershed-based conservation and recovery
plans developed under ESA, salmon recovery plans developed under
chapter 77.85 RCW, water resource plans developed under chapter 90.54
RCW, watershed plans developed under chapter 90.82 RCW, and a
regional water supply plan or water resource management plan; and
c. The county's Regional Wastewater Services Plan.
In reviewing proposals for modified and expanded service area boundaries
for municipal water suppliers, the Utilities Technical Review Committee shall
consider, in addition to Policy F-240:
a. Compliance by the water system with its comprehensive plan, including
water conservation elements; and
b. Whether it can meet its duty to provide service within its service area, as
required under chapter 43.20 RCW.
The county shall not approve a water system plan with a proposed service
area where the water system is unable to provide service for one or more of
the reasons identified in RCW 43.20.260. This does not preclude a modified
or expanded service area boundary for the water system in order to correct
problems and provide reliable potable water service within the proposed
modified service area.
F-242 The Utilities Technical Review Committee should develop a water accounting
program in conjunction with affected water utilities. The water accounting
program should coordinate information on the rate, timing, and location of
new development with the projected ability of water utilities to issue
certificates of water availability.
5. Resource Management and Protection
Water system reservoirs and watersheds often serve a number of functions. These functions can
include open space, recreation, forestry, and resource management. However, each function
must be weighed against the primary purpose of such reservoirs and watershed, which is to
provide and protect supplies of potable drinking water.
F-243 Public drinking water system reservoirs and their watersheds should be
managed primarily for the protection of drinking water, but should allow for
multiple uses, including recreation, when such uses do not jeopardize
drinking water quality standards. Public watersheds must also be managed
to protect downstream fish and agriculture resources.
F-244 Groundwater-based public water supplies should be protected by preventing
land uses that may adversely affect groundwater quality or quantity to the
extent that the supply might be jeopardized.
I. Public Sewers and On-Site Wastewater Treatment and Disposal
Systems
King County adopted the Regional Wastewater Services Plan in 1999. It called for a new north
treatment plant to be in operation by 201 O with a capacity of 36 million gallons per day (mgd).
7-11 September 2004
King County is proposing to build the new wastewater system. The Brightwater System will
include a treatment plant to provide secondary treatment of wastewater, pipelines and pump
stations to carry wastewater to and from the plant, and an outfall to discharge the treated
wastewater to Puget Sound.
King County has selected the location of the Brightwater facilities at what is referred to as the
Route 9-195th Street System with an effluent corridor along NE 195th Street and a marine outfall
in Zone 7S.
The siting process has taken many years and is the focal point of a comprehensive
Environmental Impact Statement, which is likely to be issued in November of 2003. Snohomish
County and cities in the Brightwater service area have participated actively in the siting and
environmental review process.
In addition to King County's role as the regional wastewater treatment provider, the Seattle-King
County Department of Public Health is the agency responsible for permitting on-site wastewater
treatment and disposal systems (septic systems). In addition, King County reviews sewer utility
comprehensive plans.
F-245 In the Urban Growth Area, all new development shall be served by public
sewers unless:
a. Application of this policy to a proposal for a single-family residence on
an individual lot would deny all reasonable use of the property; or
b. Application of this policy to a proposal that has a vested land use
application for the redevelopment or expansion of an existing use, as
well as an approved septic design from Public Health -Seattle and King
County, would render approval of the land use permit void; or
c. As permitted by policy CP-933.
F-246 In the Urban Growth Area, King County and sewer utilities should jointly
prioritize the replacement of on-site systems that serve existing development
with public sewers, based on the risk of potential failure. King County and
sewer utilities should analyze public funding options for such conversion
and should prepare conversion plans that will enable quick and cost-effective
local response to health and pollution problems that may occur when many
on-site systems fail in an area.
F-247 City-owned parks that are redesignated from rural to urban to allow future
annexation by a city and that are subsequently served by public sewers shall be
tightlined. This policy applies to parks that were redesignated from rural to urban
on or after September 20, 2004.
F-248 The existing public sewer system in the Town of Vashon cannot be expanded
to serve land beyond the boundaries of the town, except as provided in
Policy F-249 and as consistent with Title 57 RCW. On-site systems,
community on-site systems or decentralized treatment systems may be used
as appropriate for planned growth in other Rural Towns.
F-249 Public sewer expansions shall not occur in the Rural Area and on Natural
Resource Lands except where needed to address specific health and safety
problems threatening the existing uses of structures or the needs of public
schools or public school facilities. Public sewers may be extended, pursuant
to this policy, only if they are tightlined and only after a finding is made by
King County that no reasonable alternative technologies are technologically
or economically feasible. Utility providers shall ensure, through a signed
agreement between the school district and the utility provider, that any sewer
September 2004 7·12
service permitted for the school district is designed only to serve public
schools or public school facilities. Public sewers which are allowed in the
Rural Area or on Natural Resource Lands pursuant to this policy shall not be
used to convert Rural Area land or Natural Resource Lands to urban uses
and densities or to expand permitted nonresidential uses.
F-250 Sewer facilities such as pump stations, force mains and trunk lines that do
not provide connections to the Rural Area may be located in the Rural Area
only when they are identified in a King County-approved comprehensive
sewage system plan and upon a finding by King County that it is technically
necessary in providing service to the Urban Growth Area.
F-251 On-site wastewater treatment systems in the Rural Area and Natural
Resource Lands should be designed, built and operated as permanent
methods of sewage disposal.
F-252 King County should monitor on-site systems that have shown evidence of
failure or potential for failure. The data should be used to correct existing
problems and prevent future problems. King County should analyze public
funding options for correcting on-site wastewater system failures which may
include, where feasible and otherwise consistent with this plan, conversion
to community sewage systems or installation of public sewers.
F-253 Collective on-site systems may be used only in the following circumstances
in the Rural Area and Natural Resource Lands:
a. Existing on-site systems are failing within an area and the Seattle/King
County Department of Public Health concurs that long-term individual on-
site system repairs are not feasible and/or water quality is threatened by
the presence of or potential for health hazards resulting from inadequate
on-site wastewater disposal methods;
b. An authorized public agency will manage the community system; and
c. The community system is designed only to serve existing structures and
lots and cannot be used as a basis to increase density or to expand
permitted nonresidential uses. Substandard vacant lots must be
combined to the extent feasible to meet rural density policies.
Management of the community system must be by an authorized public
agency.
J. Solid Waste
Appropriate management of solid waste to protect the environment of King County is essential to
public health. Responsibility for management of solid wastes generated by unincorporated area
residents and businesses is shared by waste haulers certified by the Washington Utilities and
Transportation Commission and the King County Solid Waste Division.
F-254
F-255
F-256
Solid waste should be handled and disposed of in environmentally sound
ways that protect the quality of air, water and public health.
King County shall divert as much material as possible from disposal to
reduce the overall costs of solid waste management to county residents and
businesses, conserve resources, protect the environment, and strengthen
the county's economy.
Solid waste management should be planned and disposal capacity provided
on a regional basis.
7-13 September 2004
F-257 Solid waste handling facilities should be dispersed throughout the county in
an equitable manner.
K. Surface Water Management
Surface water management activities address both the quantity and quality of water entering the
natural environment. Urban areas are largely covered with impervious surfaces (e.g., buildings,
streets, parking lots) that cause increased runoff and are a source of pollutants. Management in
the Rural Area is important, too, because of the potential adverse impacts of forestry, agricultural,
and livestock practices. Prevention or mitigation of flooding, erosion, sedimentation, and water
quality and habitat degradation is important for both the built and natural environments.
F-258 To reduce flooding, erosion and sedimentation, prevent and mitigate habitat
loss, enhance groundwater recharge and prevent water quality degradation,
the surface waters of King County shall be managed through plans,
programs and regulations developed by King County in cooperation with
affected jurisdictions whenever possible.
F-259 A watershed approach shall be taken to surface water management, with
responsibility shared among King County and affected jurisdictions. This
approach should emphasize prevention of water quality degradation through
education programs and implementation of best management practices to
reduce pollution entering surface waters, including Puget Sound.
F-260 In the Rural Area, King County shall minimize the use of constructed facilities
for surface water management and maximize the use of natural systems,
provided that the ecological functions of the natural systems are not harmed.
The county should provide incentives to keep these natural systems intact.
Natural systems are also preferred in the Urban Growth Area, but it is
recognized that structural'systems will be needed to realize urban growth
and density goals. King County will plan and manage surface waters on a
watershed basis pursuant to Policies E-123 through E-129. To accomplish
this goal, water should not be diverted from one watershed into another, nor
from one drainage basin into another, unless no other reasonable alternative
is available for managing surface water run-off within the same watershed
and drainage basin. Where such diversions are permitted, King County will
require such environmental analysis and mitigation as is needed to protect
surface water resources from significant adverse impacts.
F-261 In the Urban Growth Area, regional and shared surface water management
facilities should be encouraged to support infill development to preclude the
need for individual on-site facilities, provide development incentives,
encourage efficient use of land, and reduce overall facility maintenance
costs. These facilities should be planned and financed through public and
private partnerships.
F-262 Regional and shared stormwater facilities should be funded through an
adequate and equitable funding mechanism. Stormwater facilities required
of new development should be designed and built for low-cost, long-term
maintenance.
F-263 King County should work cooperatively with other jurisdictions to develop
and implement plans and programs that address the proper treatment and/or
disposal of the wastes generated from maintenance of stormwater facilities.
September 2004 7-14
F-264 King County should work with jurisdictions to identify and agree upon
regional and local storm and surface water management responsibilities and
agree on the division of storm and surface water management service
provision.
L. Floodplain Management
Both the Washington State Growth Management Act (chapter 36.70A RCW) and Title 86 RCW,
Flood Control require interlocal consistency and coordination for effective floodplain
management. Counties have been directed to prepare comprehensive floodplain management
plans with participation of the cities. Under the King County Countywide Planning Policies
(CPPs), comprehensive floodplain management plans, regulations, and programs within all
jurisdictions in any of the major river basins in King County must be consistent with the King
County Flood Hazard Reduction Plan. As such, King County is a regional service provider for
floodplain management.
F-265
F-266
F-267
King County should participate with cities to prepare, update and implement
comprehensive flood hazard reduction plans that meet or exceed standards
established by the National Flood Insurance Program.
King County shall maintain a regional flood warning program for the major
river basins in King County.
Maintenance of flood protection facilities on the mainstem rivers in King
County should reflect a prioritized approach, based upon the Flood Hazard
Reduction Plan policies, within available funding levels. Additional funding
sources and partnerships in support of maintaining and improving flood
protection facilities should be sought whenever possible.
7-15 September 2004
11,1. Eneruv & Tel,ecommunicatio.ns
Energy and electronic communications systems are important public services that must be
coordinated with land use planning. King County's economy and quality of life depend on readily
available energy and telecommunications resources. Efficient use of energy resources can
minimize long-term costs to the individual and to society.
One or more local, state or federal agencies regulate retail energy providers in King County. Gas
and electric utility resource and conservation plans are approved by other agencies through a
public process. The Washington Utilities and Transportation Commission (UTC) reviews and
accepts plans of private electric and gas utilities, and the Seattle City Council approves the plans
of Seattle City Light. Electric and gas utilities operate in King County under franchises with the
county for use of the public right-of-way. The UTC also defines the costs that private utilities can
recover, approves rates, sets service standards and resolves customer complaints. However,
unregulated firms responding to market conditions may develop many new electricity resources.
Telecommunications services are regulated by several entities, including the Federal
Communications Commission and the Washington Utilities and Transportation Commission. King
County has some regulatory authority over telecommunications services through franchises and
the development approval process.
A. Energy
1. Consistency with Land Use Plans
State law mandates that electric and gas public service companies provide the same level of
service on a uniform basis, regardless of location. (RCW 80.28.110). Policies in this chapter
encourage the utilities to prioritize capital improvements in a manner consistent with land use.
Disruption of traffic due to public and private road projects frequently occurs in King County.
Policies in this chapter support existing programs to notify utilities of upcoming projects to build,
expand, or maintain county roads so utility and road construction can be coordinated.
Distribution systems for gas, electric and telecommunications installation in new construction now
have separate permits. Permit consolidation is desirable as a means to expedite review while
protecting the environment. Countywide Planning Policy ED-23 encourages jurisdictions to
establish a master utility project.
F-301 Energy providers' resource and facility plans should be consistent with the
King County Comprehensive Plan and should provide for a reliable source of
energy in the event of natural disaster or other potential threats of disruption
to service.
F·302 King County should coordinate public road construction and maintenance
projects with utility construction and maintenance.
2. Conservation and Alternative Energy Sources
King County Countywide Planning Policy C0-6 states that "aggressive conservation efforts shall
be implemented to address the need for adequate supply for electrical energy and water
resources, protect natural resources, and achieve improved air quality." King County has a
September 2004 7-16
continued commitment to energy conservation, use of renewable resources and quality
enforcement of the energy code.
Solar features in building design can be cost effective in the Pacific Northwest. Solar energy is
renewable, clean and reduces the use of fossil fuels. King County encourages the use of both
passive and active solar energy use through subdivision and building design.
Gas and electric utilities offer low-income energy assistance programs. All feasible actions to
increase the availability of conservation measures to low-income residents should be pursued, such
as public-private cooperation and combining existing rehabilitation efforts with installation of energy
efficiency measures.
F-303 Efficient energy consumption, conservation, the use of renewable
technologies, and energy responsible land use decisions should be a priority
in King County. King County promotes the maximum use of energy
conservation and renewable energy resources now, while leaving options for
increasing conservation and renewable technologies in the future.
F-304 To implement the Countywide Planning Policy of aggressive conservation
and promotion of regional air quality, King County should:
a. Effectively enforce the energy code as part of the general permit process;
b. Provide density incentives through the zoning code for energy-efficient
developments;
c. Continue to improve the fuel efficiency and emissions of the county-
owned fleet of motor vehicles;
d. Work with utilities to become a model of energy efficiency in facilities
owned or operated by Metropolitan King County; and
e. Seek cost-effective ways to capture energy from county operations which
other-wise would be lost, such as methane gas from landfills and sewage
treatment.
F-305 King County shall continue to explore methods of reusing or marketing
methane gas from its sewage treatment plants, and shall explore the
feasibility of expanding these methods to the methane gas produced at its
landfills.
F-306 King County encourages the use of solar energy and should protect solar
access.
F-307 King County should expand the availability of energy efficiency measures to
low-income residents.
3. Electric Utilities
The four-state Northwest Conservation and Electric Power Plan of the Northwest Power Planning
Council provides a blueprint for the development of electricity resources. Bonneville Power
Administration and other federal agencies, the region's utilities, state and local government, private
businesses and the people of the Northwest all participate in implementing the Council's goals.
Electric utilities serving King County include Bonneville Power Administration, Seattle City Light,
and Tanner Electric Cooperative. Puget Sound Energy provides both electricity and natural gas
service.
Hydropower is the largest single source of our existing electrical power, with the county's major
suppliers located outside King County. These include the Grand Coulee, North Bonneville and
Ross Dams. Federal and state approvals for hydroelectric dams are difficult and time-consuming to
acquire, making hydropower a small part of projected new regional power-generating resources.
7-17 September 2004
Existing hydropower facilities in King County include Snoqualmie Falls, Cedar Falls, Twin Falls,
Weeks Falls, and Black Creek. Proposed projects include expansion of Snoqualmie Falls and new
facilities at South Fork Tait River, Hancock Creek and Calligan Creek (both are tributaries of the
North Fork Snoqualmie), the Upper South Fork Snoqualmie and Martin Creek near Stevens Pass.
Few additional projects beyond these listed are expected to be built in King County.
The Federal Energy Regulatory Commission licenses such projects, but in doing so must consider
existing plans and policies of public and private jurisdictions. While power generation benefits the
public, care must be taken to ensure that small hydroelectric projects are constructed in an
environmentally sound manner, directing new, small hydropower facilities, for example, to streams
that do not have anadromous fish. Construction and operation must also be consistent with the
intended functions and uses of forestlands, where most small hydroelectric projects are located.
Gas-fired combined cycle combustion turbines are expected to dominate new resource additions.
These facilities typically fall below the size threshold for the Energy Facilities Site Evaluation
Council's siting process. While these facilities have a relatively small physical footprint and are
relatively clean, they do pose potential threats to local air and water quality.
F-308
F-309
F-310
F-311
To address the cumulative effects of multiple energy facilities, King County
should continue to participate in the licensing and relicensing processes for
all existing and proposed small hydroelectric projects within King County.
Individual project reviews should address consistency with designated land
uses and environmental protection goals. Specifically, hydroelectric projects
should:
a. Not significantly interfere with commercial forestry operations;
b. Be located and operated in a manner such that impacts to salmonid fish
and wildlife are minimized;
c. Avoid unstable and erosion-prone areas;
d. Include performance bonding to fund erosion control;
e. Provide full mitigation for construction and operation impacts;
f. Avoid, to the extent practicable, diminishing scenic values; and
g. Incorporate adequate public safety measures.
King County and the utilities should identify and preserve corridors to
accommodate future electric power transmission and distribution lines.
Corridor designation should include:
a. Identification of appropriate shared uses and recognition of the values
provided by nonutility uses, such as recreation;
b. Recognition of county roads as utility corridors; and
c. Evaluation of proposed facility plans on a system-wide basis, rather than
project-by-project.
When new, expanded or upgraded transmission is required, use of existing
corridors that have above-ground utilities should be evaluated first. King
County should facilitate appropriate corridor sharing among different utility
types and owners.
New electrical distribution lines should be installed underground where
reasonably feasible and not a health or safety concern. The county should
encourage underground placement of existing distribution lines through
such tools as local improvement districts.
Public concern exists over the potential health effects of electrical power lines. The concern
focuses on the effects of extremely low level electromagnetic fields, called ELF/EMF or simply EMF.
Seattle-King County Department of Public Health currently responds to inquiries from citizens about
September 2004 7-18
EMF and keeps abreast of current research. The following policy recognizes the inconclusive
nature of the data concerning EMF and the need to have an informed citizenry through public
disclosure of available research about the potential health risks. Scientific evidence to-date does
not support firm conclusions about the existence of adverse health effects related to EMF.
F-312 King County will monitor scientific research on potential human health
effects of extremely low frequency electric and magnetic fields (EMF). If
federal or state agencies promulgate rules to reduce exposure to EMF -
through changes in the use of appliances, construction practices, the
location of electrical infrastructure or other activities -the county shall
inform its citizens and take appropriate actions.
4. Natural Gas
The most thermally efficient use of natural gas is in "direct applications." For example, to heat
homes and businesses, the use of natural gas can reduce the demand for additional electricity.
The choice of fuel shall be based on market conditions, with the customer comparing various fuels.
Many homes and businesses in King County do not have the choice of natural gas, however, even
within the Urban Growth Area.
Other factors that currently limit natural gas availability include state utility regulations, building and
plumbing codes, and rebate programs that favor electric heat. Because of these barriers, most
multifamily housing is built with electric heat, a significant consideration given that they represent a
large share of projected new housing units in urban King County.
F-313 King County should work to remove barriers to the availability and efficient
use of natural gas.
5. Hazardous Liquid and Gas Transmission Pipelines
Hazardous liquid and gas transmission pipelines, as defined by RCW 81.88.040 and WAC 480-
93-005, consecutively, provide a v_ital service of transporting hazardous materials from one
location to another. Long-distance transmission pipelines move a variety of hazardous materials,
including crude oil, petroleum products, natural gas and hazardous liquids, such as anhydrous
ammonia. Pipeline rupture or failure can result in release of these materials, which are highly
flammable, explosive or toxic. The policies in this chapter identify public values and goals to
assure that the transmission of hazardous materials by pipeline address public health and safety.
The Federal Energy Regulatory Commission (FERG) regulates the location, construction and
operational conditions of interstate natural gas pipelines through its certification process. The
state and federal government regulate the location, construction and operational conditions of
hazardous liquid and intrastate gas pipelines through the Energy Facility Site Evaluation Council
(EFSEC). In its review of pipeline applications, however, EFSEC must determine whether the
pipelines are consistent with county land use plans and zoning codes. Thus, King County's
authority to regulate the location of pipelines is through the comprehensive plan and development
regulations.
F-314
F-315
King County recognizes that federal and state regulatory programs govern
the design, construction, and operation of hazardous liquid and gas
transmission pipelines. To preserve the safety and reliability of the
hazardous liquid and gas transmission pipeline system, land use, zoning and
regulations shall be consistent with state and federal requirements.
Any new hazardous liquid and gas transmission pipelines proposed for
construction in King County shall meet the county's development
7-19 September 2004
regulations, including but not limited to, King County's zoning code, building
code, grading code, and shoreline management code.
King County anticipates that few new hazardous liquid or gas transmission pipelines will be
constructed in the near future. However, as existing pipelines age and the relationship between
resources, refineries and markets changes over time, new pipelines will need to be constructed.
Hazardous liquid and gas transmission pipelines are best constructed away from locations where
large numbers of people assemble. King County recognizes however, that under some
circumstances, new gas transmission pipelines may need to locate in densely populated areas as
the only practical alternative to meet the demand for service.
F-316
F-317
F-318
New hazardous liquid and gas transmission pipelines should be located
away from high-density residential zones, Urban Activity and Business
Centers, Office Parks, sports fields, schools and day care centers or other
land uses where large numbers of people would assemble.
When new, expanded or upgraded hazardous liquid or gas transmission
pipelines are required, use of existing corridors should be evaluated first.
King County should facilitate appropriate corridor sharing among different
utility types and owners.
Hazardous liquid and gas transmission pipelines should not be located in
areas susceptible to soil disturbance or liquifaction or in aquifer recharge
areas. When it is impractical to avoid such areas, special engineering
precautions should be taken to protect public health, safety and welfare.
It is essential to map the location of existing hazardous liquid and gas transmission pipelines
within King County so that developers know where they are and whom to call for information
before construction begins. Accurate maps will assist King County in reviewing land use
applications for land uses located near pipelines.
F-319 King County should map the location of existing and new hazardous liquid
and gas transmission pipelines. Maps shall not substitute the one-call
locating system and shall not be used for any construction or maintenance
activity.
Risks to life and property can be minimized by keeping land uses a safe distance from hazardous
liquid and gas transmission pipelines. Pipelines transport a variety of materials, some of which
flow under the force of gravity. While standard setbacks do not assure protection from materials
that have the ability to migrate, setbacks may protect life and property from hazardous materials
that are highly flammable, explosive or toxic. Limiting the allowable uses within pipeline rights-al-
way can further reduce risks to life and property.
F-320
F-321
Structures designed for human occupancy shall not be located within
hazardous liquid or gas transmission pipeline rights-of-way and should be
set back from the pipeline to protect public health, safety and property. No
structures shall be located over the pipeline.
Land uses shall be restricted within hazardous liquid and gas transmission
pipeline rights-of-way. Passive recreational uses, such as hiking trails, may
be allowed if the risk to life and property is assessed and determined to be
minimal.
Pipeline failure can result from damage caused by excavation near existing pipelines. Many
existing pipelines initially were constructed in less-populated areas with little development. As
September 2004 7-20
•
demand for land grows, the risk of conflict between existing pipelines and land development
increases.
F-322 King County should promote the safety and reliability of the hazardous liquid
and natural gas transmission pipeline systems by requiring developers,
contractors, and excavators to notify the state, pipeline operators and
utilities through the one-number locator service, before beginning excavation
or construction.
F-323 In the interest of safety and reliability of the hazardous liquid and natural gas
interstate transmission pipeline systems, the county should take steps to
protect and preserve the signs that mark pipelines.
6. Natural Gas Distribution Systems
Natural gas pipelines fall into two major categories: gas transmission lines that transport natural
gas from production fields to local distribution companies and distribution systems tHat deliver
natural gas from transmission pipelines to retail customers. The federal government may define
certain parts of the natural gas distribution system that serve large volume gas users as part of the
transmission system. Distribution systems for transporting natural gas are fundamentally different
from transmission gas pipelines and should be regulated based on their design, use and location.
Gas distribution systems are owned and operated by local distribution utilities. Such systems
consist of the pipelines that deliver natural gas to end users together with intermediate supply
lines. The distribution system is constructed incrementally, with addition of new segments and
upgrading of existing lines in numerous small projects. The distribution system is a network that
is primarily located in road rights-of-way, where service is available. Local distribution companies
are subject to the comprehensive safety regulations administered by the Washington Utilities and
Transportation Commission (WUTC) under state law and regulations and by the federal Office of
Pipeline Safety under federal law and regulations. The rates and services of investor-owned
utilities also are subject to comprehensive regulation by the WUTC under state law and
regulations.
F-324
F-325
F-326
F-327
F-328
King County recognizes that the gas distribution system is primarily located
in road rights-of-way.
King County should promote the safety and reliability of the natural gas
distribution pipeline systems by requiring developers, contractors, and
excavators to notify the state, pipeline operators and utilities through the
one-number locator service, before beginning excavation or construction.
In the interest of safety and reliability of the natural gas distribution pipeline
systems, the county should take steps to protect and preserve the signs that
mark pipelines.
Structures designed for human occupancy shall not be located within gas
distribution pipeline rights-of-way and should be set back from the pipeline
to protect public health, safety and property. No structures shall be located
over the pipeline.
Permit requirements shall require excavators to ensure adequate protection
of any facilities that are encountered during their work. This shall include but
not be limited to adhering to the foreign facility owners requirements for
separation and backfill, developing joint plans when drilling or boring parallel
to foreign facilities, and potholing all facilities that will be crossed by drilling
or boring.
7-21 September 2004
B. Telecommunications
1. Telecommunications
Telecommunication technologies are changing rapidly and will continue to change during the
horizon of this plan. The future telecommunication system may make little distinction between
cable, telephone and cellular. Telecommunication services include voice, data, video and other
communication services on various mediums including, but not limited to, wire, fiber optic or radio
wave. Effective telecommunications services are critical to citizens in several ways. They promote
and enhance individual information exchange, contribute to a robust regional economy, and afford
numerous public services, including delivery of emergency services, education and opportunities for
citizen involvement.
F-329 King County complies with the Telecommunications Act of 1996 and
provides the widespread availability of telecommunication systems to
facilitate communication between and among members of the public, public
institutions and business in both the urban and rural areas.
F-330 Telecommunication services are to be encouraged as a means to mitigate the
transportation impact of development and growth.
F-331 Long-term planning for telecommunications construction, reconstruction and
facility upgrades should include provisions to insure that the system's
capacity, design and equipment will allow users to take advantage of
innovative uses, services and technology.
F-332 Telecommunication companies and the county should coordinate activities
when facilities are being installed or road construction projects are
scheduled.
F-333 Long-term planning for telecommunications systems should allow
uninterrupted service during natural disasters.
F-334 Colocation of telecommunication facilities is encouraged to reduce the
unnecessary proliferation of individual, single-user towers. Colocation shall
be required unless an applicant can demonstrate to the satisfaction of the
county that colocation on an existing tower is not feasible and not consistent
with service quality and access.
F-335 Although visual impacts are always an important consideration in the
decision to approve or deny a proposal, King County shall give greater
weight to the visual impacts of telecommunication facilities proposed to be
located on residentially-zoned lands or in the Rural Area. In addition, the
visual impacts of proposals for an individual tower with a single user shall be
given greater weight than proposals to colocate facilities.
F-336 King County considers the placement of telecommunication facilities within
street rights-of-way as the preferred alternative to the construction of
facilities on private property. Regulatory standards shall require placement
in street rights-of-way, especially within residential neighborhoods and Rural
areas, unless such a location is not feasible or not consistent with service
quality and access.
2. Cable Services
September 2004 7-22
King County Ordinance No. 10159 dictates current policy for cable services. It states in part:
" it is the County's policy to promote the widespread availability of cable service and
diverse information to County residents and to encourage the development of cable
systems and cable technology as a means of communication between and among
members of the public and public institutions."
The county's cable-related needs are expressed in the following policies:
F-337 Long-term planning for cable systems should include service to all areas of
the county which meet the minimum density established in the cable
company's franchise agreement and the county's Cable Television
Ordinance.
F-338 Cable companies should provide services that meet the cable-related needs
and interests of all segments of the community, taking into account the cost
of meeting such needs and interests.
F-339 Cable companies should take affirmative steps to ensure that reasonable
services are available regardless of income or the income of other people in
the person's neighborhood.
F-340 The goal of long-term cable planning should be a high-capacity, state-of-the-
art system. Two-way capacity should be installed and activated. Cable
systems should be interconnected to other communications systems. They
should be designed to be "open"; that is, the systems should be usable by
many, for a variety of purposes.
F-341 Public uses of the cable system should be expanded as the system is
upgraded.
3. Internet Access
Rapidly changing technologies are providing opportunities for alternative work environments and
lifestyles as more people transmit and receive information through the internet. While there is a
growing interest in the use of computer technologies, few new developments are including high-
speed internet access lines or home cabling. King County encourages private partnering between
developers, builders and communication providers to expand the opportunities for access to the
internet.
F-342
F-343
Developers should collaborate with major employers to create developments
that facilitate and encourage telecommuting by installing high-speed internet
lines during construction of the project.
Builders and architects should work with the telecommunication industry to
design state-of-the art cable-ready homes and offices.
7-23 September 2004
Cha ter Ei ht
Communitv Plans
Cha ter Ei ht
Communitv Plans
Though typically separate from the King County Comprehensive Plan, some community plan
policies have been incorporated into the comprehensive plan. These policies apply to specific
geographic areas of King County. The original community plan policy number appears in
parentheses at the end of each policy.
Between 1973 and 1994 King County prepared community plans for 12 subareas of
unincorporated King County. The first generation of community plans, substantially completed by
1984, were used to implement the county's 1964 Comprehensive Plan, and consisted of detailed
land use policies, area zoning, and lists of capital projects (primarily roads and parks) for each
planning area. The second generation of community plans, from 1985 to 1994, implemented
many concepts of the 1985 King County Comprehensive Plan (for example low-density zoning for
rural areas, resource lands and environmentally sensitive areas, higher urban residential
densities, and development guidelines for major urban activity centers such as Kenmore) that
were carried over to the 1994 King County Comprehensive Plan.
Under King County's pre-Growth Management Act (GMA) planning system, if a community plan
conflicted with the comprehensive plan, the community plan governed. Under the GMA, the
comprehensive plan prevails over "subarea" plans (RCW 36.70A.080(2)). The 1994 King County
Comprehensive Plan spelled out the relationship between the comprehensive plan and
community plans and directed the county to review community plans and repeal or revise them to
eliminate conflicts. The county has reviewed the community plans adopted between 1973 and
1994 and determined that, while most community plans' policies are redundant (or in a few cases
in conflict with the 1994 Comprehensive Plan), some are area-specific or issue-specific and
should be readopted as part of the comprehensive plan.
Although the community plans (except for the Vashon Town Plan, West Hill, and White Center -
see Section XIII) are no longer in effect as separately adopted plans, in many cases the published
plan documents contain valuable historical information about King County's communities and
other information that provides background for the policies listed below and for the portions of the
local pre-GMA area zoning that remain in effect.
The following section contains those community plan policies that are readopted as part of the
King County comprehensive plan, and community plan policies that have been amended through
subarea plans. This section also contains policies that have been adopted subsequent to
community plans, but are specific to individual community planning areas.
8-1 September 2004
I. Bearcreek
The Bear Creek Community Plan became effective in February 1989, and directed most forecast
growth into a concentrated area near the City of Redmond Watershed, first referred to as the
"Novelty Hill Master Planned Developments." The rest of the Bear Creek Plateau was designated
for a mixture of suburban and rural residential development. The 1994 King County
Comprehensive Plan redesignated most of the planning area as rural. In 1995, some of the Bear
Creek Community Plan's policies relating to the Novelty Hill Master Planned Developments
(MPDs) were amended by Ordinance 11954. Also, the 1994 Comprehensive Plan refers to MPDs
as Urban Planned Developments (UPDs). After the 1994 Comprehensive Plan's urban
designation of the UPD sites was appealed and remanded to the county, the sites in question
were redesignated for Fully Contained Communities (FCCs) as defined in the Growth
Management Act, as well as UPDs (See policy R-104 in Chapter 3). The readopted policies for
the most part address Novelty Hill and some area-specific transportation and trail issues.
CP-101
CP-102
September 2004
To provide a range of housing opportunities and accommodate a fair share of
growth in Bear Creek, the Novelty Hill subarea should be designated an urban
planned development (UPD) and fully contained community (FCC). This
designation will be implemented by urban planned development. (BC-3)
Urban planned development will be permitted in the Novelty Hill subarea only
when the following planning policies are met:
a. To protect existing wetlands, streams and wildlife habitat, urban planned
development shall be consistent with the intent of King County
ordinances, King County Comprehensive Plan policies and sensitive
areas regulations. The design of the proposed development shall protect
and preserve existing wetlands, streams and wildlife habitat by several
methods including (but not limited to) minimizing alterations to the
natural drainage features, maintaining water quality, preserving storage
capacity, providing undisturbed unique/outstanding wetlands and
undisturbed or enhanced buffers, restricting the number of stream
crossings, and minimizing erosion and sedimentation. To achieve the
intent of this policy it may be necessary to exceed the requirements of the
King County wetland guidelines.
b. A master drainage plan for the Novelty Hill subarea shall be approved by
King County.
c. New development adjacent to a unique/outstanding or significant wetland
should preserve or enhance the wetland and provide an undisturbed
buffer around the wetland adequate to protect its natural functions.
Encroachments into significant wetlands may be allowed when no
feasible alternative exists and enhancements are provided to replace the
lost wetland functions; and
d. Groundwater recharge areas should be identified and protected to ensure
that groundwater resources are protected from potential pollution.
e. To ensure that the existing road system in both King County and
Redmond is not adversely affected, on-site and off-site traffic impacts
shall be mitigated consistent with the Integrated Transportation Program
(K.C.C. chapter 14.65).
f. A project environmental impact statement (EIS) shall be required for all
property proposed for urban planned development within the UPD
8·2
)
•
CP-103
CP-104
CP-105
development area. The project EIS shall address the full range of public
services necessary to serve urban development on Novelty Hill. The EIS
shall include the cost of these services, the financial responsibility of the
developer(s) and affected jurisdictions, and the method of phasing
development to coincide with availability of these public services.
g. Since the remainder of residential land in Bear Creek will either be
recognized as existing one-acre neighborhoods or designated as rural
areas, all improvements to public facilities, including but not limited to
road construction and sewers, shall be financed by the UPD developers
provided the impacts are the result of UPD developments or according to
a fair-share formula agreed to by affected parties.
h. A full range of housing densities, types and prices including housing for
low-, moderate-, and medium-income groups shall be included in the
UPD. The mix of single-family and multifamily housing in the UPDs shall
approximate the existing county housing stock mix.
i. Urban planned development shall maintain and keep open for public use
identified major equestrian and hiking trails.
j. Urban planned development shall provide active recreation facilities that
adequately serve the needs of future residents and employees.
k. Urban planned development shall provide a minimum of 25% open space
in addition to the preservation of all surveyed wetlands.
I. The Novelty Hill urban planned development area shall contain an urban
activity center, which includes a commercial center to provide for the
everyday shopping needs of the planned UPD population.
m. The activity center shall also contain a business park of sufficient size to
provide a diversity of employment opportunities and a balance of jobs
and households for the UPD area.
n. In order to preserve opportunities for a variety of employment types in
the business park areas, retail development in freestanding buildings
should be excluded. Up to 10% of gross floor area in business park
buildings may be planned for retail uses, such as restaurants and
business services, to serve business park employees.
o. Development conditions for the shopping and business park areas
should encourage high quality development and site design.
The area will revert to rural if UPD development is denied or not pursued. If
the UPD area reverts to rural, the zoning shall be RA-5. (BC-4)
Sewer facilities necessary to serve urban planned development on Novelty
Hill are planned, designed and constructed to serve only such development
and are prohibited from serving nearby surrounding low-density urban and
rural areas. Proposals to extend sewer service or expand urban development
outside the Novelty Hill subarea are not appropriate and are inconsistent with
the purpose of the King County Comprehensive Plan. (BC-5)
The Novelty Hill urban planned development or fully contained community
shall contain a commercial area of sufficient size to serve the future residents
and employees. (BC-17)
The natural drainage systems of Bear, Evans, and Patterson Creeks should
be restored, maintained, and enhanced to protect water quality, preserve
existing aquatic habitat, reduce public costs, and prevent environmental
degradation. Public improvements and private developments should not
alter natural drainage systems without mitigating measures which eliminate
8-3 September 2004
CP-106
CP-107
CP-108
CP-109
CP-110
CP-111
CP-112
September 2004
increased risk of flooding and erosion, negative impacts on water quality,
and loss on aquatic or riparian habitat. (BC-32)
An undisturbed corridor wide enough to maintain the natural biological and
hydrological functions of streams should be preserved in all new
development in the Bear Creek Planning Area. (BC-34)
Bear, Evans, and Patterson Creeks and their tributaries should be protected
from grazing animal access in order to: 1) reduce water quality degradation
from animal wastes, 2) reduce bank collapse due to trampling, and 3) allow
shading vegetation to reestablish along stream banks. (BC-35)
Streams channeled in the Bear, Evans, and Patterson Creek drainages should
not be placed in culverts unless absolutely necessary for property access.
To reduce disruption to streams and their banks, bridges should be used for
stream crossings, and crossings should serve several properties. When
culverts are required, oversized culverts with gravel bottoms that maintain
the channels' width and grade should be used. (BC-38)
New development should rehabilitate degraded stream channels and banks
in the Bear, Evans, and Patterson Creek drainages to prevent further erosion
and water quality problems. Where conditions permit, the banks and
channels should be restored to a natural state. (BC-39)
Unique or significant wildlife should be identified and preserved.
Development plans should identify significant wildlife habitat and should
locate buildings, roads, and other features on less sensitive portions of the
site. These considerations may result in a reduction in density from that
otherwise allowed by zoning. (BC-40)
The Bear and Evans Creeks' watersheds have been designated as critical
areas for protection of the aquatic resources and human health. The
following surface water management activities should be promoted.
a. Appropriate and reasoned changes in land use policies and regulations
may be evaluated during the preparation of the Bear/Evans Creeks Basin
Plan.
b. Ensure adequate field inspection of land development activities.
c. Implement a public information program to promote water resources and
stream channel protection.
d. The Bear and Evans Creeks Basin Plan shall develop recommendations
for water quality monitoring and recommended methods for citizen input
and evaluation to assess the success of the county's policies and
regulations pertaining to this planning area. (BC-41)
Mitigation of traffic impacts to the City of Redmond arterial system will be
accomplished through the interlocal agreement process. The Avondale
arterial corridor study recommendations shall be used as a basis for traffic
mitigation requirements for both city and county development affecting the
corridor.
Mitigation shall preserve the operational integrity of the corridor and maintain
existing local access. The primary arterial corridor between the Novelty Hill
urban area and SR-520 should be located and designed to encourage transit
and ride-sharing alternatives to single-occupant vehicle travel.
8-4
CP-113
CP-114
CP-115
CP-116
CP-117
CP-118
Transportation planning of new facilities and management of the
transportation system should be coordinated with current and forecast needs
of the East Sammamish and Northshore planning areas, adjacent areas of
Snohomish County, and with the cities of Redmond and Kirkland, and should
be a cooperative effort of the affected jurisdictions. Phasing of Bear Creek
and Redmond development should be strongly linked to the provision of
adequate transportation facilities and travel demand management programs.
(BC-45A)
Establishment of new rights-of-way and acquisition of additional right-of-way
in existing corridors should emphasize protection of natural systems and
adequate buffering of existing and potential residential development. (BC-47)
Road improvements in Cottage Lake, Ring Hill, Ames Lake, Union Hill, and
the rural areas should incorporate design features such as grass-lined
swales to minimize surface water disruption and to protect and enhance
water quality. (BC-49)
196th Avenue Northeast ("Red Brick Road") between Union Hill Road and
Redmond-Fall City Road (SR-202) is a historic road and should be preserved
by restoring its brick surface, limiting vehicular loads and speeds, and
prohibiting access to commercially-zoned properties to the west. Access to
these properties should be provided by other existing roads and by a new
north-south road connecting Union Hill Road and 185th/187th Avenues
Northeast. (BC-50)
Park-and-ride and park-and-pool lots should be developed in Redmond,
Cottage Lake, Ring Hill, Ames Lake, and Union Hill to provide focal points for
transit and ride sharing. Park-and-pool lots should be located in rural areas
along major commuting corridors such as SR-202, Redmond-Fall. City Road,
Novelty Hill Road, and Woodinville-Duvall Road. (BC-52)
The Northwest Gas Pipeline and Puget Sound Power Line should be
established as regional trails in Bear Creek to tie in with the East Sammamish
planning area and to connect with the King County Toi! Pipeline Trail and the
Snoqualmie Valley Trail. (BC-61)
When the development of property occurs in Bear Creek, adequate rights-of-
way should be provided for trail use. Trails should connect to existing and
proposed schools, parks, riding stables, and recreation areas. (BC-62)
8-5 September 2004
1:1. East S8IODl81DiSb
The East Sammamish Community Plan was adopted in December 1992. The East Sammamish
Community Plan Update became effective in June 1993. Most of the planning area was
designated for urban development, but important rural areas included Happy Valley, Grand Ridge
and the eastern edge of the Sammamish Plateau. For the most part, the 1994 King County
Comprehensive Plan reaffirmed the land use designations of the East Sammamish Community
Plan Update. The major changes from the community plan occasioned by the 1994
Comprehensive Plan were replacement of the "urban reserve" approach to grow1h phasing with
the service and finance strategy outlined in the 1994 Comprehensive Plan and designation of a
portion of Grand Ridge for urban grow1h. Most of the readopted policies address drainage,
transportation and road design. ·
CP-201
CP-202
CP-203
CP-204
For all new development, increased standards for retention/detention, water
quality facilities, and monitoring shall be considered, adopted and
implemented as appropriate within the areas identified in surface water
management basin planning and reconnaissance study areas. (NE-1)
As new roads are built and existing roads widened, special consideration
shall be taken to create or retain the aesthetic character of the area through
the use of vegetated buffers that utilize native vegetation. (NE-3)
Control mechanisms equal to or more effective than those adopted by
Ordinance 9365 limiting or removing phosphorus and other non:Point source
pollutants from water bodies should be established and implemented as
special requirements in area-specific basins plans to provide added
protection to streams, lakes, wetlands. The Lake Sammamish Water Quality
Management Project Report and, upon their adoption, the Issaquah Creek
and East Lake Sammamish Basin and Non-point Source Control Plan, the
Pine Lake Management Plan and the Beaver Lake Management Plan
recommendations should be implemented to protect water bodies from non-
point source pollution. (NE-7)
Development shall protect wildlife through site design and landscaping. New
development within or adjacent to the wildlife habitat network should
incorporate design techniques that protect and enhance wildlife habitat
values. (NE-10)
CP-205 All golf course proposals shall be carefully evaluated for their impacts on
surface and groundwater quality, sensitive areas, and fish and wildlife
resources and habitat. (NE-11)
CP-206 Water used for irrigating golf courses should come from nonpotable water
sources wherever possible. Use of natural surface water sources, such as
streams, should be avoided due to impacts on fish and other wildlife habitat.
A water conservation plan shall be submitted with golf course applications
which should address measures such as the use of drought-tolerant plant
species. (NE-12)
September 2004 8-6
CP-207
CP-208
CP-209
CP-210
CP-211
CP-212
CP-213
CP-214
The Patterson Creek Basin currently provides highly-productive aquatic
habitat. Urban development within this basin should be conditioned to
protect this resource by minimizing site disturbance, impervious surfaces
and disturbances of wetlands and streams. (No Community Plan Policy
Number)
The Northwest Pipeline office and maintenance shop is an existing use and is
recognized by this plan as providing a needed service to the area. This 6.5
acre site may redevelop for pipeline utility and/or school bus base uses
exclusive of major maintenance functions that are compatible with the
surrounding rural development and agricultural uses. Redesignation of
additional properties in the immediate vicinity of Northwest Pipeline for
manufacturing park uses or other urban uses shall not be permitted. (Cl-13)
New developments should be designed and constructed with an internal road
system which includes a Neighborhood Collector linking with existing or
planned adjacent developments, creating a complete Neighborhood Collector
circulation system and such linkage should be designed to ensure safety of
local streets. Through traffic on local access streets should be discouraged.
(T-9)
Metropolitan King County Government should establish park-and-ride
facilities in the East Sammamish Community Planning area. Park-and-ride
facilities should be built along 228th Avenue and/or adjacent to 1-90 and SR-
202. The park-and-ride lots should be sited adjacent to and connect with
existing or proposed community or neighborhood centers or within the
employment center located around the intersection of E. Lake Sammamish
Parkway and SE 56th Street. Establishment of a site near, but to the north of,
1-90 should be high priority response to current and anticipated 1-90 access
problems. (T-13)
Consistent with the King County Open Space Plan, the county shall
encourage establishment of an open space system in East Sammamish and
give priority to protecting recreational, cultural and natural and sensitive
areas such as shorelines, aquifer recharge areas, wildlife habitat, historic
properties, archaeological sites, scenic vistas and community separators or
greenbelts. The county may require lot clustering within or adjacent to open
space areas; linkages between open spaces and may provide density
bonuses or incentives to developers who preserve significant open space or
establish trails beyond usually applied mitigation. (P-11)
Urban separators should be established to provide visual relief from
continuous development, provide important linkages for wildlife habitat, and
maintain a visual separation between distinct communities. (P-17)
There are areas within the urban separators that are especially suitable for
trail connections for recreational use by present and anticipated population.
King County should develop a trail and/or parks system utilizing the
preserved open space within the urban separators. (P-18)
When the development of properties occurs in the East Sammamish planning
area, public access or easements should be required to complete the
development of a local trail system for those areas where existing trails have
historically been used by the public, or where the King County Open Space
8·7 September 2004
September 2004
Plan identifies proposed trail alignment for regional and local trails. The
Parks Division shall review the application during the development review
process. (P-23)
B·B
111. Enumclaw
The Enumclaw Community Plan and Area Zoning were commenced in 1986-87 and adopted in
June 1990. The community plan refined boundaries between the Enumclaw Plateau's Agricultural
Production District and abutting Rural Areas and Forest Production District, and designated the
Urban Growth Area agreed to by King County and the City of Enumclaw. The 1994 King County
Comprehensive Plan reaffirmed the Enumclaw Community Plan's land use designations.
CP-301
CP-302
CP-303
All development within 660 feet of the top of the Green River valley walls
should be conditioned lo avoid adverse impacts on the environment and
risks to life and property. (EN-12)
King County should work with landowners on either side of SR-410 east of
the City of Enumclaw to protect the scenic qualities of this highway corridor.
(EN-22)
King County should work with Washington State Parks and Recreation
Commission and landowners on either side of the Green River Gorge to
protect the scenic qualities of the Green River Gorge conservation area.
(EN-23)
Enumclaw's expansion area, like that of other rural cities, is shown on the King County
Comprehensive Plan Land Use Map.
CP-304 King County should work with the City of Enumclaw to establish an
agreement guiding future annexations, including but not limited to the
following elements:
a. Commitment from the city to extend and maintain public services to the
area, including police, fire, transportation, sewer, water, storm water
management and general government services.
b. Commitment from the city to provide a variety of residential development
at an overall density for unconstrained land of at least four to eight units
per acre.
c. Commitment from the city that the extension of public services to meet
the needs of future residents will maintain service levels to existing city
residents.
d. Commitment that the city will continue environmental protection for
sensitive areas, (including but not limited to flood plains, steep slopes,
wetlands, seismic and landslide hazard areas) at or above King County
standards.
e. Commitment from the city to use measures to buffer or protect abutting
forest or agriculture resource lands.
f. Commitment that the city will provide protection of historic sites and
areas equal to the county's Historic Preservation Ordinance.
g. Commitment by King County to consult with the city on public
improvement standards, such as local road standards, drainage control
requirements and transportation standards that will apply to development
in expansion areas.
8-9 September 2004
h. Commitment by King County to notify the city of development proposals
in the expansion area and to consult with the city to condition
development approvals to mitigate adverse impacts on city services and
to implement city plans, policies and standards.
i. Commitment by King County to notify the city of development proposals
in an impact area, which includes all lands within a one-mile radius of the
expansion area, and to consult with the city where applicable to condition
development approvals to mitigate adverse impacts on city services.
j. Agreement on which jurisdiction will have responsibility for parks, roads,
storm water or other public facilities after annexation. (EN-40)
CP-305 Access to state park lands should be designed to minimize adverse traffic
impacts on the Southeast Green Valley Road. (EN-56)
CP-306 Any expansion of aircraft runway or hangar capacity in the Enumclaw
planning area should be concentrated on or near the existing Enumclaw
airport. Existing legally approved landing strips associated with low-density
residential developments, such as Evergreen Sky Ranch, shall not be
expanded. (EN-60)
CP-307 Redevelopment of the Enumclaw landfill site should be subject to studies to
assure public health and safety. If these studies determine that there is no
threat to public health and safety the site's rural designation may be changed
to accommodate a public use such as a park or other facility without an
amendment to the King County Comprehensive Plan. (EN-71)
September 2004 8· 1 0
IV. Federal wav
Work on the Federal Way Community Plan and/or amendments occurred from 1972 to 1975,
1977 to 1980, and 1984 to 1986. Federal Way was part of the first generation of community plans
in the county that were adopted separately from their implementing area zoning. After these
experiences, the county decided to adopt both together to avoid going through essentially the
same decisions twice for each community. The City of Federal Way incorporated in 1990,
removing most of the planning area from the county's jurisdiction. None of the Federal Way
Community Plan or its amendments are readopted.
8-11 September 2004
V. Hluh.llne
Highline has one of the longest histories of any community planning area. Between its original
adoption in 1976 as the "SeaTac Communities Plan" and adoption of the 1994 King County
Comprehensive Plan, the High line Community Plan has been updated or amended 13 times, and
has been partially or wholly replaced by plans for smaller areas within Highline (e.g., West Hill,
Burien Activity Center, White Center Community Action Plan, and SeaTac). The City of SeaTac
incorporated in 1990, the City of Burien incorporated in 1993, and numerous portions of the
planning area have been annexed by Tukwila and Des Moines. Although the planning area as a
whole has grown slowly since 1970, the incorporations and annexations have resulted in a
massive decrease in the unincorporated area population (down over 38 percent between 1990
and 1994).
None of the Highline Community Plan is readopted with the exception of West Hill and White
Center which were adopted in 1994 as part of the comprehensive plan but published separately.
(See Section XIII.)
September 2004 8-12
VI. Newcastle
The Newcastle Community Plan commenced in 1 978 and was adopted in May 1983. The final
adopted plan designated three sites for Master Planned Developments (MP Os), but stipulated that
only two MPDs could occur without an update of the community plan. One MPD was approved by
the county in the late 1980s. Bellevue annexed Factoria and Newport Hills in 1993 and the City of
Newcastle was incorporated in 1994, so the noncity portion of the planning area's population fell
13 percent between 1990 and 1994 even though the whole planning area is forecast to grow
almost 18 percent between 1994 and 201 O. The planning area also includes some areas
designated Rural by either the 1985 or 1994 King County Comprehensive Plans.
CP-601
CP-602
CP-603
King County supports the nomination of the Odd Fellows Cemetery and
counterbalance right-of-way to the National and State Registers of Historic
Places. (N-33)
Limit grazing animal access to May Creek and its tributaries in order to 1)
reduce water quality degradation from animal wastes, 2) reduce bank
collapse due to animals' hooves, and 3) allow shading vegetation to
reestablish along stream banks. (N-41)
May Creek is acknowledged as a regional asset and should be protected.
Thus, King County shall not increase zoning density on lands that drain into
May Creek (i.e. the May Valley Basin) without first determining and
implementing surface water runoff mitigation necessary to control flooding
and siltation in May Creek.
8·13 September 2004
VII. Norths.ho.re
The Northshore planning area has been one of King County's faster-growing planning areas. The
first "Northshore Communities Development Plan" began in 1972-73 and was adopted in August
1977. Almost immediately the Northshore Community Plan Revision Committee was established,
and the "Revised Northshore Community Plan" was adopted in 1981.
The latest Northshore Community Plan Update began in July 1988 and was adopted in February
1993. During 1993, the newly incorporated City of Woodinville assumed jurisdiction within its
territory. Portions of the planning area have been annexed by Bothell, Kirkland and Redmond.
Kenmore, a significant unincorporated activity center, became a city in August 1998.
CP-701 The north and east slopes of Norway Hill have an established neighborhood
character and limited future development potential. They are, therefore,
designated low density urban, 1 home per acre. King County recognizes that
extensive steep slopes and erosive soils at the top of Norway Hill (above the
300-foot elevation mark) warrant lower residential densities. (E-10)
CP-702 The undeveloped area to the south of Metro's Brickyard Park and Ride lot
should retain its office-only designation in recognition of its proximity to a
major transportation corridor and the need for increased employment
opportunity in proximity to planned high-density residential areas. (E-13)
CP-703 King County, Snohomish County, the City of Bothell, and the City of
Woodinville should work on specific areas of mutual concern, such as the
Swamp Creek and Daniels Creek drainage basins, the SR-527 transportation
corridor, the proposed regional facilities of the University of Washington, and
the future expansion of the City of Bothell. (E-25)
CP-704 Swamp Creek provides important wildlife habitat and serves as an urban
separator between Kenmore and Bothell. To protect the Swamp Creek
corridor, no development should be allowed in the Swamp Creek floodplain.
Residential development shall be clustered away from the tributary, as
defined in the area zoning. (R-7)
CP-705 Significant vegetation is a diminishing resource in the Northshore
community. Significant vegetation contributes significantly to environmental
quality, neighborhood character, and the quality of life in Northshore. All new
residential development shall retain significant existing vegetation. Native
vegetation should be utilized wherever possible. (R-17)
CP-706 New development must provide pedestrian connections to off-site facilities
such as existing trails, walkways, community facilities and services, transit,
schools and surrounding residential neighborhoods. Pedestrian links should
be provided internally in all new residential development. Bicycle and
equestrian links should be provided where possible. (R-19)
CP-707 King County recognizes the importance of existing mobile home parks in
providing affordable housing options. Mobile home parks outside of the
September 2004 8-14
CP-708
CP-709
CP-710
CP-711
CP-712
CP-713
CP-714
Woodinville and Kenmore commercial core areas are designated for mobile
homes park uses, and shall be zoned appropriately.
King County shall continue to examine the feasibility of funding and
developing a replacement mobile home park in north King County for
displaced mobile homes on county-owned or privately owned sites.
King County should develop interlocal agreements with the cities of Bothell,
Redmond, Kirkland, Woodinville and Kenmore for joint development of
replacement parks to accommodate mobile home owners if they are
displaced from mobile home parks within cities. (R-21)
Roadway improvements addressing the transportation needs in the
Sammamish Valley from the South Woodinville bypass to northeast 124th
Street should carefully preserve the rural character of the valley as indicated
by this and other adopted land use plans. Incorporating roadway design
characteristics, such as tree windbreaks and shoulders instead of curb and
gutter, will enhance this rural atmosphere. Access from adjacent properties
to the proposed Willows Road extension shall be discouraged. Where
access is necessary from adjacent properties, access shall be consolidated.
(T-11)
King County should improve motorized and nonmotorized transportation
circulation east and west across the 1-405 corridor to provide relief in the
congested Totem Lake and Kingsgate areas. The county should also
cooperate with other jurisdictions. (T-12)
Transit improvements and HOV treatments on 1-405 and SR-522 should be
given highest priority. This may include developer contributions to these
improvements as part of the development review process. (T-25)
Transportation projects in Northshore should incorporate bicycle friendly
design, utilizing a variety of design techniques appropriate to the particular
project and right-of-way characteristics, including, but not limited to, bicycle
lanes, wide outside travel lanes, paved shoulders, bicycle sensitive signal
detectors, and appropriate signing. Existing bicycle facilities should be
preserved or enhanced when general road improvements are made. Secure
parking for bicycles should be provided at activity centers throughout
Northshore. (T-33)
Pedestrian and bicycle linkages are encouraged and should be planned.
There should also be a link for equestrian uses from Hollywood Hill and NE
171 st Street to the Sammamish River trail in the vicinity of the South
Woodinville CBD bypass. (W-14)
Protection of natural vegetation coverage at levels sufficient to moderate
surface water runoff and erosion and to protect the integrity of stream
channels should be required through special zoning requirements, critical
drainage basin requirements, or countywide ordinance. When revegetation is
required, appropriate native vegetation should be used. (NR-4)
Until such times as the Sammamish River Basin Plan is adopted, special
attention should be given to the Reconnaissance Report #1 O during the
development review process. The comprehensive plan land use map should
8-15 September 2004
be amended, if analysis through the Sammamish River Basin Plan indicates a
need to modify adopted land uses in order to protect water resources of the
Sammamish Basin. (NR-8)
CP-715 Unique geologic conditions in Northshore have resulted in hillsides that have
a high risk of large scale erosion. Increased on-site retention/detention
requirements in areas drainage over steep and erosive slopes should be
adopted and implemented as special zoning requirements. (NR-9)
CP-716 A community-wide trail system for pedestrians, equestrians, and bicyclists
should be developed. This trail system should connect regional trails with
local trails and walkways. (P-6)
CP-717 When the development of properties occurs in the Northshore Planning Area,
public access or easements should be required to complete the development
of a local trail system. Adequate right-of-way should be provided for trail
use. To ensure that the provision of trail corridor right-of-way does not result
in a reduction in the number of permitted building lots, the area within the
trail right-of-way, not otherwise credited as part of a road right-of-way
dedication, should also be credited toward the lot area of any proposed
development. Trails should connect to existing and proposed schools,
parks, riding stables, recreation areas and neighborhoods. (P-9)
CP-718 King County should work closely with other jurisdictions and public agencies
to seek appropriate trail links between elements of the open space system
including, but not limited to the Burke-Gilman trail, Sammamish River trail,
and the Tolt Pipeline Trail. (P-10)
CP-719 Existing public access points to the Sammamish River should be maintained
and additional access points acquired and developed to ensure the use of
this river as trail corridor and fishing area. (P-11)
CP-720 King County should transfer ownership of county-owned property located
north of NE 145th, south of 148th Street, west of 124th Avenue NE and east of
119th Avenue NE to the cities of Bothell and Kirkland in order to preserve it
for park and open space purposes. (P-16)
September 2004 8-16
VIII. Shoreline
The Shoreline Community Plan was commenced in March 1977 and adopted in August 1980.
The new City of Shoreline commenced operating in August 1995; between Shoreline and Lake
Forest Park the planning area has very little unincorporated territory left, all of which is in one or
the other city's Potential Annexation Area (PAA).
All of the unincorporated share of the planning area's 2012 household growth target will be
accommodated within the new City of Shoreline. Therefore, none of the Shoreline Community
Plan's policies are readopted.
8-17 September 2004
11. soo,qaailmia va111e1
The Snoqualmie Valley Community Plan was initiated in April 1984, and adopted in August 1989.
The process resulted in designation of the Snoqualmie Ridge Urban Growth Area for the City of
Snoqualmie. The area was annexed by the City of Snoqualmie, and development is proceeding
under an interlocal agreement as directed by the community plan. The 1994 King County
Comprehensive Plan largely reaffirmed the Rural and Resource Lands land use map designations
of the community plan.
CP-901
CP-902
CP-903
CP-904
CP-905
September 2004
King County, in cooperation with the Valley cities, and state and federal
agencies, should conduct a study of baseline conditions and cumulative
impacts of development on the Snoqualmie River's water quality, and
identify methods of equitably controlling these impacts. (SQP-1 through
SQP-6)
Wildlife populations in the Snoqualmie Valley planning area are
recognized as a regionally important resource and an important
characteristic of the area's rural character. Special studies should be
undertaken, in cooperation with the Washington State Department of
Wildlife, to identify wildlife populations at risk due to the land uses
allowed by the King County Comprehensive Plan and to develop
mitigation measures to protect the continued viability of the area's
wildlife populations. Should these studies indicate unmitigatable impact
affecting wildlife populations due to the land uses allowed by the plan, a
comprehensive plan amendment study will be undertaken to provide for
the continued existence of this valuable resource. (SQP-17)
Properties in erosion-prone drainage basins are subject to special
development conditions applied to protect the safety and property of
county residents through reducing or eliminating the occurrence of gully
formation and sever erosion. These conditions may include:
a. A drainage control plan;
b. Installation of drainage control features prior to any land clearing,
vegetation removal, site grading, road construction, or utility
installation; and
c. Runoff control requirements. (SQP-21)
King County will oppose annexations to Snoqualmie Valley cities that
currently contain designated floodplain lands until interlocal agreements
have been enacted to advance the policies and standards set forth in the
comprehensive plan. (SQP-27)
The Shoreline Environment designations of the King County Shoreline
Management Program should be consistent with comprehensive plan
land use map designations and zoning. King County should initiate the
shoreline redesignation process consistent with K.C.C. 25.32.130. (SQP-
32)
8-18
CP-906 Until expansion areas are annexed, zoning for the expansion areas shall
be urban reserve at 5 acre densities with the exception of the existing
commercial/industrial area in the SE North Bend Way expansion area, and
the existing industrial area in the Snoqualmie expansion area. (SQP-57)
Community plan policies SOP 58 to 61 referred to "expansion areas one and two," reflecting the
Snoqualmie Community Plan's attempt to phase growth of the valley cities. These phasing
approaches were embodied in the interlocal agreement the county signed with the City of
Snoqualmie; they may be reflected in the cities' comprehensive plans. The King County
Comprehensive Plan simplifies the designations into one expansion area for each city.
CP-907
CP-908
CP-909
CP-910
CP-911
CP-912
King County will support development within the Snoqualmie Valley cities
of Duvall, Carnation, Snoqualmie and North Bend and annexation and
development of lands within their expansion areas, when each city
demonstrates that its wastewater and storm water treatment systems for
the existing and proposed city jurisdiction will not degrade the water
quality of the Snoqualmie River and its tributaries. (SQP-58)
King County will not support Snoqualmie Valley cities' annexations into
expansion areas until each city has adopted mechanisms to reduce or
eliminate flood hazards within its jurisdiction. (SQP-59)
King County shall initiate an amendment to the King County
Comprehensive Plan if the cumulative impact of development of the
cities' expansion areas will reduce the quality of the Snoqualmie River
and its tributaries below the current "A and AA" standards. (SQP-61)
King County will not support any annexations by a Snoqualmie Valley city
until it can be demonstrated that building permits have been approved at
urban densities for development of at least one-half of the
environmentally unconstrained land in all the annexations by the rural
city since January 1990. Exceptions to this policy may be considered by
King County subject to an interlocal agreement and where all other
applicable policies herein are satisfied. (SQP-62)
The county shall oppose an annexation by a Snoqualmie Valley city
unless it lies within approved service areas as designated by
comprehensive plans for water and sewer, is accompanied by all the
proposed amendments to extend water and sewer comprehensive plan,
or the area is already adequately served by such utilities. (SQP-63)
King County shall work with the City of Carnation in a public process with
citizen participation to enter into an interlocal agreement to allow joint
planning for a planning and service area including land northeast of
Carnation. The purpose of the interlocal is to insure that further
development of these lands does not materially impact the character or
vitality of the city or the viability of the surrounding resource lands.
Elements of the interlocal agreement shall include:
a. The agreement shall expressly recognize the City of Carnation's
ability to extend by contract public water and the city shall be the
preferred water purveyor within the service area, provided that
densities remain at rural residential levels as identified in the King
County Comprehensive Plan;
8·19 September 2004
CP-913
CP-915
CP-916
CP-917
CP-918
b. An arrangement for coordination on SEPA action required for
development proposals within the planning area;
c. Visibility of proposed new development from the City of Carnation
shall be addressed and mitigated;
d. Water quality issues shall be addressed and mitigated. (SQP-67)
King County shall support annexation of the expansion area only when
Carnation implements a long-term, nonstructural program to reduce flood
damages on floodplains land within its jurisdiction. (SQP-68)
Achieving a long-term solution to flood damages within the City of
Snoqualmie is one of King County's highest priorities for this planning
area. (SQP-70)
King County reaffirms its support for the spirit and intent of the
Snohomish Mediated Agreement, and the recommendations of the
Snohomish River Basin Coordinating Council which led to the signing of
the intergovernmental agreement for implementation. King County
considers this work to be a sound basis for a long-term flood damage
reduction program for the City of Snoqualmie. (SQP-72)
King County intends to assist the City of Snoqualmie to develop a long-
term solution and an implementation program which will solve flooding
problems in the city. (SQP-73)
If the long-term solution to flooding problems in the City of Snoqualmie is
determined to have basin:wide impacts, these impacts shall be reviewed
by the King County flood control management plan team or its equivalent
to identify any additional mitigations which may be required. If the long-
term solution to flooding problems is demonstrated to not have basin:
wide impacts, it should be implemented as soon as possible and would
not require a second, basin-wide, review of impacts and mitigations.
(SQP-74)
King County urges a public/private resource commitment to implement a
long-term solution to flooding problems in the City of Snoqualmie.
(SQP-75)
Policies SOP 76 through 78 have been and continue to be implemented through an interlocal
agreement. Most of the annexations referenced have taken place and are reflected in the
expansion area boundaries for the City of Snoqualmie adopted in the King County Comprehensive
Plan·s Land Use Map.
CP-919
CP-920
September 2004
Until a long-term solution to preventing flood damages in the City of
Snoqualmie is agreed to by King County and the City of Snoqualmie, King
County will support annexations in expansion areas when consistent with
all appropriate policies herein and when higher residential densities can
be achieved, municipal services can be provided, and river water quality
will not be degraded. (SQP-77)
Annexations of lands within the Phase 1 and Phase 2 additions to the City
of Snoqualmie's Urban Growth Area shall not occur until completion of
detailed planning, preparation and review of project-level Environmental
Impact Statement(s), and a determination of required mitigations and
B-20
CP-921
CP-922
CP-923
CP-924
CP-925
CP-926
CP-927
amenities. The range of land uses to be allowed and the mitigations and
amenities to be required shall be embodied in a binding Development
Agreement between the City of Snoqualmie and the owners of proposed
annexation lands.
The project-level Environmental Impact Statement(s) for lands within the
Phase 1 and Phase 2 additions to the City of Snoqualmie's Urban Growth
Area shall address aquifer recharge issues, and potential impacts to the
water quality and quantity of Lake Alice, private wells in the Lake Alice
and Snoqualmie Hills neighborhoods, and all streams that flow off-site.
Based on the findings of the Environmental Impact Statement(s), the
Development Agreement between the City of Snoqualmie and the owners
of proposed annexation lands in the Phase 1 and Phase 2 additions to the
City of Snoqualmie's Urban Growth Area shall establish a program for
long-term monitoring of the water quality and quantity of Lake Alice and
the private wells in the Lake Alice and Snoqualmie Hills neighborhoods,
and of all streams flowing off-site.
The Development Agreement shall also outline the remedies necessary if
the monitoring program leads to findings that development activities on
the annexation lands are the cause for adverse impacts to the water
quality and/or quantity of Lake Alice and the private wells in the Lake
Alice and Snoqualmie Hills neighborhoods, and of streams flowing off-
site. The owners of the annexation lands shall be responsible for the
monitoring program and correction of any impacts determined to have
been caused by their development activities. Remedies may include
connection to the public water system, or construction of alternative
wells.
The project-level Environmental Impact Statement(s) for lands within the
Phase 1 and Phase 2 additions to the City of Snoqualmie's Urban Growth
Area shall address traffic safety issues, with a focus on safety concerns
for rural homeowners dependent upon the southern stretch of the
Snoqualmie Parkway for access to their homes. A range of alternatives to
improve safety at the intersection of the Snoqualmie Parkway and SE
96th Street, including signalization, road widening and turn lanes shall be
explored.
Annexations of lands within the Phase 1 and Phase 2 additions to the City
of Snoqualmie's Urban Growth Area shall be subject to updated
Comprehensive Water and Sanitary Sewer Plans to determine the full
range of improvements landowners within the annexation will be required
to provide.
A Drainage Master Plan shall be required for any new development of
lands within the Phase 1 and Phase 2 additions to the City of
Snoqualmie's Urban Growth Area. Stormwater facility design shall
adhere to the standards in the most recent update of the King County
Design Manual, or of the Snoqualmie Storm Drainage Plan, whichever is
the most stringent.
There shall be no road connections between the Phase 1 addition to the
City of Snoqualmie's Urban Growth Area and 356th SE in the Snoqualmie
8·21 September 2004
CP-928
CP-929
CP-930
CP-931
CP-932
Hills Planning Area, unless future analysis determines a restricted
emergency access is necessary for safety purposes.
There shall no be no road connections between the Phase 2 addition to
the City of Snoqualmie's Urban Growth Area and Lake Alice Road, unless
future analysis determines a restricted emergency access for Lake Alice
residents is necessary for safety purposes.
To protect the rural character of the neighborhoods surrounding the
Phase 1 and Phase 2 additions to the City of Snoqualmie's Urban Growth
Area, the Phase 1 and Phase 2 areas shall include buffers to all rural
lands along their perimeter. The size and structure of each buffer area
shall be determined based on the characteristics of the land and existing
vegetation, and its ability to perform the following functions: visual
screening; noise reduction; and minimization of blow down. Buffers may
include constructed berms and new plantings if deemed necessary and
appropriate to perform the required functions.
King County supports the continued industrial use of Weyerhaeuser's
Snoqualmie Mill site and its annexation to the City of Snoqualmie. (SQP-
79)
King County will support annexations of land in North Bend's expansion
area when higher residential densities can be achieved, municipal
services can be provided, and river water quality will not be degraded.
(SQP-81)
Commercial and light industrial land uses are appropriate along SE North
Bend Way subject to special development conditions to mitigate impacts.
(SQP-82)
A map is included in Appendix A to Ordinance 12824 (p-suffix conversion ordinance) showing the
application of p-suffix conditions to commercial and industrial properties on SE North Bend Way.
CP-933
CP-934
CP-935
September 2004
Commercial and industrial zoned land (including potential-commercial or
potential-industrial zoned land) within the City of North Bend's Urban
Growth Area (UGA) are planned for nonretail, resource-based and
highway-oriented uses. These uses shall be served by public sewers. If
by December 31, 2006, the City of North Bend has not created any new
wastewater treatment capacity, or has refused to allow connection for
such uses, King County shall amend its policies and development
regulations to allow wastewater treatment with on-site systems, provided
there are no impacts to groundwater.
The area between Tanner and the Edgewick Interchange, south of SE
140th and north of 1-90, is appropriate for nonretail commercial and light
industrial land uses. Commercial and light industrial uses shall be
limited to uses that do not impact ground water and are related to
resource-based shipping, distributing and trucking-related industrial
development. (SQP-84)
Land uses adjacent to the Edgewick Interchange shall be limited to
highway-oriented commercial uses that do not impact ground water, and
serve the traveling public. (SQP-85)
8·22
CP-936 The area north of the Edgewick Interchange is appropriate for resource-
based, shipping, distributing and trucking related industrial uses that do
not impact ground water. (SQP-86)
The Fall City policies in this section were revised through a subarea planning process involving
members of the Fall City community in 1998 and 1999. Through this planning process, the
Citizens Advisory Committee identified the following elements that local residents value about
their town:
• It is surrounded by agricultural and forest lands which are entirely rural;
• It has a pattern of development that has evolved over more than a century, which includes
historic buildings and landmarks, an open spacing of streets and buildings, and locally owned
businesses in a small-scale downtown;
• It is located in a unique geographic area formed by the confluence of two important salmon-
bearing rivers, the Raging River and the Snoqualmie River, in an agricultural valley containing
a number of other salmonid streams that are also important to the ecology of King County;
• Compatible home occupations and small-scale animal husbandry in harmony with residential
neighborhoods:
• Rural-level street improvement (e.g., no traffic lights, no sidewalks outside the business
district, and no street lights except as needed for public safety):
• Scenic vistas, open space, and rural and resource uses surrounding Fall City; and
• Small rural town identity.
CP-937
CP-938
CP-939
CP-940
CP-941
Fall City is an unincorporated rural town which should have overall
residential densities of one to four dwelling units per acre. Potential
commercial zoning adopted in the 1999 Fall City Subarea Plan may be
actualized through an area-wide rezone initiated by the King County Council
once alternative wastewater treatment systems or public sewers are
available.
The zoning for Fall City adopted in the 1999 Fall City Subarea Plan reflects
the community's strong commitment to its rural character, recognizes
existing uses, provides for limited future commercial development, and
respects natural features. Additionally, it recognizes the current and long-
term foreseeable rural level of utilities and other public services for the area.
The land use implications of a major change in the water supply or a public
health requirement for community-wide wastewater collection and treatment
may be evaluated in a new community-based planning process; however this
does not mean that zoning will change to allow more intense development
beyond that adopted in the 1999 Fall City Subarea Plan. The rural character
of Fall City should be preserved.
Within the residential area of Fall City, compatible home occupations and
small-scale agricultural pursuits or similar rural land uses can continue.
King County should work with the State of Washington and the Fall City
community to make transportation improvements in Fall City that will favor
safe and pleasant pedestrian and other non motorized links between
downtown businesses, the residential areas, and nearby King County Parks,
and safe walkways to schools, rather than rapid through traffic.
King County should expand the soft surface pedestrian, equestrian and
bicycle trail opportunities serving the Fall City area. Trail route options
serving the community shall be reviewed to include a route along the left
8-23 September 2004
CP-942
CP-943
CP-944
CP-945
CP-946
bank levee easement directly adjacent to the Raging River, historically used
by the public as a pedestrian, equestrian and bicycle trail. This historically
used trail generally follows the "wildlife corridor" along the bank of the
Raging River from 328th Way SE approximately NE to the Preston Fall City
Road. The selected trail system for the Fall City area shall be identified in the
King County Parks and Recreation trail system plan.
Zoning for the existing industrial and office areas adopted in the 1999 Fall
City Subarea Plan should be maintained but not expanded.
Land uses at freeway interchanges without existing commercial or industrial
development, and outside rural neighborhoods and rural cities, are
designated rural residential to support development in rural neighborhoods
and rural cities, and to preserve the scenic nature of the corridor. (SQP-98)
New development at the Exit 22 Interchange shall not expand beyond the
area designated in this plan and shall not adversely impact surrounding rural
residential areas. All uses should be planned and sited to use long-term
onsite waste disposal systems. (SQP-99)
The existing two acres of land currently zoned for commercial use at Preston
(Exit 22) is recognized, but no additional land for commercial uses is
designated. (SQP-100)
The presence of the Snoqualmie Tribe in the planning area has important
historic and cultural significance for the Puget Sound region. The following
places, recognized by the tribe as historically, culturally and archeologically
important, should be considered for inclusion in the King County historic
sites survey, and designation to local and/or national register of historic
places.
The tribe recognizes the following areas as culturally significant:
a. Snoqualmie Falls;
b. The banks of the Snoqualmie River between the falls and the three forks
confluence area;
c. Fall City Indian Cemetery;
d. Banks at the confluence of Snoqualmie and Raging Rivers;
e. Banks at the confluence of Snoqualmie and Toll Rivers;
f. Fall City Park (site of John Sanawa's Council House and the first white
school);
g. Mt. Si; and
h. Granite outcropping used as a quarry between North Bend and the City of
Snoqualmie on SR-202. (SQP-122)
CP-947 King County recognizes the spiritual, historic, cultural and recreational value
of the Snoqualmie Falls. Any development adjacent to Snoqualmie Falls shall
be designed and sited to protect these values. (SQP-123)
CP-948 Because of the spiritual significance of the area at the base of the falls to the
various tribes in the Puget Sound region, this area of the falls should remain
free of development and open for public access. (SQP-124)
September 2004 8-24
CP-949
CP-950
CP-951
CP-952
CP-953
CP-954
The community of Preston is a significant cultural and historic reminder of
the planning area's roots in the logging industry. The existing land use
designation shall be maintained, and new development should respect the
existing character of the community. (SQP-125)
The industrial area adjacent to the Rural Neighborhood of Preston shall be
recognized with appropriate zoning for industrial uses. This area is
designated for industrial uses to recognize existing industrial use and vested
applications for new industrial development.
The boundaries of this industrial area are permanent. No expansion of the
designated industrial area will be permitted, and any effort to expand its
boundaries is recognized as contrary to the Growth Management Act,
including the 1997 amendments.
Any industrial development or redevelopment in the designated industrial
area (excluding reconstruction in the event of accidental damage or
destruction, or tenant improvements entirely within the building structures)
shall be conditioned and scaled to maintain and protect the rural character of
the area as defined in RCW 36.70A.030(14) and to protect sensitive natural
features.
New industrial development or redevelopment (excluding structures and site
improvements that existed or are vested by applications as of May 24, 1996,
or tenant improvements entirely within building structures), on Jots not
subject to restrictions and conditions consistent with those reflected in
Recording No. 9708190805 must be dependent upon being in the Rural Area
and must be compatible with the functional and visual character of rural uses
in the immediate vicinity and must not encourage or facilitate conversion or
redesignation of nearby Rural and Rural Neighborhood lands to commercial,
industrial or urban uses.
The boundaries of this industrial area shall be those properties within the
Preston Industrial Water System, as set by King County Ordinance 5948, with
the exception of parcel #2924079054.
King County supports efforts of the community of Preston to achieve
recognition of its historical and cultural significance. Its historic character
should be maintained through designation as an historic area. (SQP-126)
The King County Historic Sites Survey should be updated to include
additional sites identified by the Preston Heritage Committee. (SOP-127)
The development of a regional railroad museum in the Snoqualmie area is
encouraged to promote understanding of the regional significance of
railroads in the settlement and development pattern of Washington State.
(SOP-128)
King County shall put high priority on the acquisition and development of a
regional trail system linking the Snoqualmie Valley planning area to other
parts of the county. (SQP-143)
8·25 September 2004
CP-955 King County supports designation of the Middle Fork of the Snoqualmie
River under either the national or state Wild and Scenic River program. (SQP-
151)
CP-956 King County supports evaluation of the North Fork of the Snoqualmie River
and the main stem of the Toll River under either the national or state Wild and
Scenic River program. (SQP-152)
CP-957 King County shall assist the City of North Bend, when requested, to develop
a long-term solution and an implementation program which will solve
flooding problems in the city.
September 2004 8-26
X. Soos Creek
Soos Creek is one of King County's largest and fastest growing planning areas. The first Soos
Creek Plateau Communities Plan (SCCP) commenced during the fall of 1975, and was adopted in
November 1979. The process was controversial, partly because Soos Creek served as a
laboratory for several emerging planning concepts, including a Rural land use designation
implemented with zoning limiting residential density to one home per five acres.
The Soos Creek Community Plan Update commenced in March 1988 and was adopted in
December 1991. In 1995 the City of Kent initiated annexation of a very large area between it and
Lake Meridian, intended to encompass most of its Potential Annexation Area (PAA) within the
planning area. The cities of Maple Valley and Covington have commenced operating and
assumed jurisdiction within their territories.
CP-1001
CP-1002
CP-1003
CP-1004
The continued viability and health of the Soos Creek planning area's stream
systems and the fisheries resources dependent upon them should be
assured through zoning, special zoning conditions and development
regulations. The intent of this policy is to control densities along stream
corridors identified by the Soos Creek Basin Plan. This policy will be
implemented through the Area Zoning by placing rural and urban densities
within 1/4-mile of significant stream systems identified as Types 1, 2, and 3
waters according to the Sensitive Areas Ordinance. (NR-1)
Lot coverage limitations for building shall be applied in all stream corridors in
urban designated areas of the Soos Creek basin and classified R-1, urban
stream protection special district overlay. Total impervious surface should
not exceed 8%, and total clearing of forested vegetation should not exceed
30%. Reforestation to achieve sites that are 70% forested should be required.
(NR-1A)
New development should rehabilitate degraded wetlands and stream
channels and banks in the Soos Creek planning area's drainage's to prevent
further erosion and water quality problems. These areas include, but are not
limited to, May Creek, Garrison Creek, Molasses Creek and Olsen Creek.
Where conditions permit, the banks and channels should be restored to a
natural state. Where it has been determined that additional standards may be
appropriate to control volume, these should be required for new
development. (NR-3)
Within the Soos Creek basin, bare ground associated with clearing, grading,
utility installation, building construction, and other development activity
should be covered or revegetated between October 1 and March 31 each
year. Earth-moving and land-clearing activity should not occur during this
period within the Soos Creek basin except for regular maintenance of public
facilities and public agency response to emergencies that threaten the public
health, safety and welfare. Landscaping of single-family residences, existing
permitted commercial forestry and mining activities and development sites
with approved and constructed drainage facilities that infiltrate 100 percent of
surface runoff should be exempt from these restrictions. (NR-8)
8·27 September 2004
CP-1005 For new subdivisions in the Soos Creek basin Rural Area, a minimum of 20%
of the property should be retained as a separate tract of undisturbed
indigenous vegetation. (NR-9)
CP-1006 All development within 660 feet of the top of the Cedar River Valley and the
Green River Valley walls, particularly along the bluffs south and west of the
Lea Hill plateau and within the Lake Heights area, should be conditioned to
avoid adverse impacts on the environment and risks to life and property.
(NR-14)
CP-1007 The Soos Creek Community Plan recognizes the importance of existing
mobile home parks in providing affordable housing options. Mobile home
parks in the urban areas of Soos Creek are designated for mobile home park
uses, and should be zoned appropriately. King County should continue to
examine the feasibility of funding and developing a replacement mobile home
park in south King County for displaced mobile homes on county-owned or
privately-owned sites. King County should develop intergovernmental
agreements with the cities of Renton, Kent and Auburn for joint development
of replacement parks to accommodate mobile home owners if they are
displaced from mobile home parks within cities. (R-23)
CP-1008 Significant vegetation is a diminishing resource in the Soos Creek
community. Significant vegetation contributes significantly to environmental
quality, neighborhood character, and the quality of life in Soos Creek. All
new residential development shall retain significant existing vegetation.
Native vegetation should be utilized wherever possible. (R-33)
CP-1009 Multifamily zoned land should not be converted to institutional and
commercial/office uses within the Soos Creek Planning Area. (C-5)
CP-1010 Equestrian crossings of arterials should be permitted only where they do not
greatly disrupt traffic. Where possible, these crossings should be combined
with pedestrian and bicycle crossings. There should be no at grade
equestrian crossings of SR-516, except at Lake Meridian. (T-29)
CP-1011 Crest Airpark is an important local facility and should continue operation at
current levels of use. (F-15)
CP-1012 Because of noise and public safety concerns, low-density, single-family
development should be the primary land use allowed within Crest Airpark's
north flight path within 1/2:mile of the airport runway. (F-16)
CP-1013 All new subdivisions within 1/4-mile of Crest Airpark should include a
covenant. The covenant should state that the property owner and/or resident
recognize the existence of Crest Airpark, its value to the community, and the
noise and public safety aspects of living in proximity to the airpark. (F-17)
CP-1014 The operation of SIR is expected to continue indefinitely. The area
authorized for racetrack use shall be confined to maximize protection of Little
Soos Creek and its riparian area. Any future consideration of permits for its
operation should be consistent with the spirit and intent of the 1991 rules and
conditions which regulate operation of the facility. (F-18)
September 2004 8-28
CP-1015
CP-1016
CP-1017
King County should give high priority to expanding the Big Soos Creek trail
by linking the City of Covington to the south and Fairwood Center to the
north to the existing trail system. (P-15)
King County should give high priority to linking the Green River and Cedar
River corridors. (P-16)
King County should coordinate with the City of Seattle, WSDOT, and other
jurisdictions to link major elements of the open space system including the
Cedar River, Lake Desire, Big Soos Creek, SR-18 and the Green River trail
systems. ( P-18a)
8-29 September 2004
11. Tahoma/Baven Heights
The Tahoma/Raven Heights planning area is the second largest (149 square miles) and was the
second-fastest growing community planning area during 1990-1994. The Tahoma/Raven Heights
Communities Plan (T/RH) commenced in August 1979 and was adopted in October 1984. T/RH
continued to apply the Growth Reserve and Rural designations and zoning that emerged during
the Soos Creek planning process. The planning area is mostly unincorporated Rural or Forest
Production District. In the years prior to the Growth Management Act (GMA) the City of Black
Diamond completed one large annexation. A final Urban Growth Area for Black Diamond has
been determined and may be adopted as part of future amendments to the 1994 King County
Comprehensive Plan. The planning area has also been affected by the incorporation of the new
City of Maple Valley. The city has commenced operation and assumed jurisdiction. It includes
most of the Urban Growth Area in the planning area.
In response to data and recommendations emerging while the Soos Creek Basin Plan was being
prepared, interim 5-acre zoning was applied to portions of the Jenkins and Covington Creek
watersheds in July 1989. AT/RH Update covering about one-fifth of the planning area was
initiated in March 1991, and adopted in December 1991. The area zoning was changed in some
cases, but this action was based on the 1985 King County Comprehensive Plan and applicable
basin plan policies, and did not result in any changes to the 1984 T/RH policies.
CP-1101 Resource activities should be encouraged in areas where such activities are
not inconsistent with a rural atmosphere. In order to ensure continued
development of natural resources prior to the development of the land for
other purposes, extractive industries should be allowed to locate in areas
known to have deposits of minerals. Premature urban/ suburban
development should not be approved which forecloses the opportunity to
use the resources. (T/RH-28)
CP-1102 The demand from surrounding land uses and densities should not exceed the
capacity of the area's groundwater resources nor otherwise cause
deterioration of its quality. (T/RH-45)
CP-1103 Existing businesses which qualify as legal uses located at Highway 169 and
Cedar Grove Road should be given the same land use map designation as
surrounding rural or resource properties, but recognized as Rural
Businesses with neighborhood-scale business zoning. Any such
development should not be expanded beyond the limits of the existing
zoning of the specific parcel on which it is currently located, and if the use is
abandoned the zoning should be redesignated to a rural zone consistent with
that applied to surrounding properties.
C-1104 King County supports annexation of the lands within the City of Black
Diamond's Urban Growth Area subject to the requirements of the Black
Diamond Urban Growth Area Agreement as adopted by Ordinance 12534. If the
agreement is terminated, the affected lands under King County jurisdiction
shall be treated as follows:
a. Land within the designated Urban Growth Area shall be redesignated to
Rural and reclassified to the rural zoning in place prior to the effective date
September 2004 8-30
CP-1105
CP-1106
of Ordinance 12534. This zoning shall continue for a period of at least five
years from the date of reclassification.
b. The areas identified in the agreement as county open space shall be
maintained at the rural zoning in place prior to the effective date of
Ordinance 12534. This zoning shall continue for a period of at least five
years after the date of termination of the agreement.
King County supports expansion of the network of regional trails and
conservation of natural resource lands and environmentally sensitive areas
through community efforts such as the Rock Creek Valley Conservation Plan
and the Friends of Rock Creek.
King County supports efforts to protect and enhance open space and ensure
long-term habitat health and passive recreation opportunities in the Middle
Green River through community efforts such as the Middle Green River
Coalition.
8-31 September 2004
XII. Vashon
The Vashon Community Plan commenced in the spring of 1977 and was adopted in June 1981.
Due to concerns about Vashon-Maury Island's water supply, which consists of local rain-fed
aquifers, a revision to the plan was set for 1986 after completion of the Vashon/Maury Island
Water Resources Study. The revision process began in April 1984, and the updated Vashon
Community Plan was adopted in October 1986. In addition to responding to the Water Resources
Study, the plan update also implemented the 1985 King County Comprehensive Plan's
designation of the entire planning area as Rural. In 1996 the Vashon Town Plan repealed or
modified several of the 1986 plan's policies, and adopted new policies and area zoning to guide
development in the unincorporated Rural Town of Vashon. The Vashon Town Plan was adopted
as a subarea plan and therefore is part of the King County Comprehensive Plan, as provided by
the Growth Management Act (GMA). The policies below are the issue-or area-specific policies
retained from the 1986 plan.
CP-1201
CP-1202
CP-1203
CP-1204
CP-1205
CP-1206
CP-1207
September 2004
All of Vashon-Maury Island is recognized for its unique ecological functions
as a Puget Sound island, and is designated in this plan as a rural area.
Development activities should protect the entire ecological system, including
the Puget Sound shoreline, island habitat areas, and ground and surface
water resources. (V-1)
All land use policies and regulations for Vashon shall reflect the overriding
importance of the fact that the whole Island is the recharge area for a single-
source aquifer. All of Vashon Island shall therefore be considered a
groundwater recharge area. Within the Island, based largely on soil types,
there are areas of relatively high, medium, and low susceptibility to
groundwater contamination. Areas deemed highly susceptible to
contamination in the KCCP should receive extra protection. (V-3)
Home occupations should continue to be allowed in residential areas on
Vashon Island. (V-27)
Development should be minimized and carefully managed in sensitive areas.
The most fragile, hazardous or valuable areas, including areas highly
susceptible to contamination, landslide hazard areas and wetlands, should
remain largely undeveloped through application of a low density designation.
(V-31)
Protect and preserve the Island's wildlife habitats. (V-33)
Where fish or wildlife habitat occur within a proposed short plat or
subdivision, the proposal should be reviewed to ensure that the ingredients
necessary for the habitat's preservation are not destroyed. Special
conditions should be attached to protect the habitat, if necessary. (V-34)
Fish and wildlife habitats identified on Vashon Island and considered to be
especially unique and valuable or of potential countywide significance
should receive special attention. Where these occur within a proposed plat
or subdivision, Department of Development and Environmental Services
(DDES), or its successor, may require the developer to submit a special
8-32
report to assess more closely the impacts of the proposal on the habitat and
to recommend specific measures to protect them. (V-35)
Most fisheries in King County are regulated by agencies other than the county. Policies
throughout this plan address fish habitat and the response to ESA listings. A harvestable fisheries
habitat not otherwise addressed is the intertidal shellfish habitat on Vashon Island. The King
County Department of Natural Resources and Parks owns some of this habitat. While the State
of Washington governs the harvest of some species in this habitat, the county should take
affirmative action to assure long-term productivity and to protect public health. The 1997 report of
the Beach Assessment Program documents the degradation of this resource from over-
harvesting. increased beach use and other causes.
CP-1208
CP-1209
CP-1210
CP-1211
CP-1212
CP-1213
CP-1214
CP-1215
CP-1216
Intertidal shellfish habitat on Vashon Island shall be protected for its key role
in the marine food chain, to protect public health, and to assure long-term
productivity. King County shall explore effective means to protect this
fisheries resource.
Island water resources should continue to be the sole water-supply source in
the future. The plan discourages importing water for domestic uses from off
the Island. (V-52)
Land uses and development densities should be planned so that demands on
the Island's groundwater resources do not exceed its capacity to provide
adequate supplies without deterioration of quality. In order to achieve this,
ongoing research and monitoring as recommended in the Vashon Maury
Island Water Resources Study should be conducted. (V-53)
Protection of the groundwater aquifer is of primary importance to Vashon
Island. Further water quality degradation which would interfere with or
become injurious to existing or planned uses should not be allowed. (V-54)
To protect domestic water resource, areas deemed highly susceptible to
groundwater contamination and watersheds should be maintained in
residential or similarly nonintensive uses at low densities. (V-57)
As an additional requirement for the comprehensive plans of public water
systems on Vashon Island, the county shall ask that information be included
assessing the ability of existing and potential water sources to meet
anticipated population growth. Planned expansion of the water system
should be prohibited if the analysis reveals a risk to the adequacy of service
including quality of water being provided to current users. (V-59)
Special consideration should be given to the impacts of new development on
the Island's groundwater resources. This should apply to major
developments, development in areas highly susceptible to contamination, or
development near public water supplies. (V-61)
Park-and-Ride lot development both on the Island and at or near the ferry
terminals which serve Vashon Island (Fauntleroy, Southworth, Pt. Defiance)
should be encouraged. (V-67)
Provide a safe and efficient system of commuter and recreational routes for
bicyclists, pedestrians, and equestrians. (V-69)
8-33 September 2004
CP-1217
CP-1218
CP-1219
CP-1220
CP-1221
CP-1222
CP-1223
CP-1224
CP-1225
CP-1226
CP-1227
Street and highway improvements should be low-cost safety and
maintenance projects wherever possible. (V-71)
Additional water-related parks and beaches should be acquired along the
saltwater shorelines of Vashon-Maury Islands. These parks should be
retained as passive, natural areas. (V-83)
Additional park sites should be acquired in the island's most environmentally
sensitive natural areas. These sites should be retained as passive, open
space areas allowing only those uses that would be compatible with sensitive
areas. (V-84)
A public trail system should be identified and encouraged for preservation on
Vashon Island. (V-85)
Trails on Vashon Island should serve bicyclists, equestrian and pedestrian
uses. (V-85a)
Trail systems at parks and on other public land should be encouraged on
Vashon Island. Trails on public lands should be officially recognized and
preserved. (V-85b)
If and when county-and state-owned land on Vashon is logged, trails should
be preserved for equestrian and pedestrian use. If possible, an unlogged
buffer zone should be left when logging occurs. (V-85c)
Voluntary dedication of trails should be encouraged when land is developed
for more intensive uses. (V-85d)
Trails should provide multiple uses where possible, serving both recreational
and commuter needs. (V-85e)
Trail corridors on Vashon Island should be established and designed based
upon the following criteria:
a. Connect park and open space areas;
b. Provide access to shoreline areas, particularly public parks;
c. Incorporate views and other special features of scenic, historic, or
archaeological interest;
d. Traverse development limitation areas where not incompatible with
hazard or fragile natural areas;
e. Follow streambanks and ravines;
f. Follow undeveloped rights-of-way or along side existing roads; and
g. Provide access to and connect schools. (V-85f)
The quantity and quality of Vashon-Maury Islands' groundwater supply
should be monitored, along with building permit and subdivision data, to
determine if planned densities can be achieved. If new information indicates
the groundwater supply is endangered, the County shall take immediate
steps to ensure new development does not impair the groundwater supply.
Vashon-Maury Island is unique within King County in that it is an island community dependent
upon a designated sole-source aquifer for its water supply. Given that the only source of drinking
water is ground water, a higher level of protection of groundwater recharge is warranted on
Vashon-Maury Island than in the rest of King County. Land clearing and building activities can
September 2004 8·34
reduce groundwater recharge. Low-impact development (LID) is a new approach to land
development that involves protecting and enhancing native vegetation and soils, reducing
impervious suriace and managing storm water at the source. These techniques are well suited to
development in rural-residential zoned areas and can be an effective way to protect groundwater
quality and recharge.
CP-1228 King County should work with residential builders and developers on
Vashon-Maury Island to encourage the use of low impact development
practices that protect and enhance native vegetation and soils and reduce
impervious surface. King County should promote preservation of at least
65% forest cover on rural-residential zoned parcels. The 65% forest cover
goal may be adjusted for parcels less than 2 Y, acres in size. Dispersion of
runoff from impervious surfaces into native vegetation in accordance with
the Surface Water Design Manual shall be the preferred method of
stormwater management in the rural area.
8-35 September 2004
111 11. west Hill/White Center
The West Hill and White Center Community Plans, applying to portions of the original Highline
Community Plan, were the last adopted by King County (West Hill in 1993, White Center in 1994),
and as such were prepared in conformance with the Growth Management Act (GMA), and are
already incorporated as part of the 1994 King County Comprehensive Plan. They will be reviewed
and possibly revised as part of a future revision to this plan.
September 2004 8-36
Chapter Nine
Implementation
Chapter Nine
Implementation
The comprehensive plan guides land use over the long term by applying specific land use
designations throughout the unincorporated portion of the King County and by providing guidelines
for implementing regulations used to evaluate specific development proposals. To ensure that
these implementing regulations are effective and warrant a high degree of public trust and
confidence, the regulations must be equitable, reasonable and responsibly administered.
1-101 King County's regulation of land use should:
a. Protect public health, safety and general welfare, and property rights;
b. Protect consumers from fraudulent practices in land use, land sales and
development;
c. Implement and be consistent with the comprehensive plan and other
adopted land use goals, policies and plans;
d. Be expeditious, predictable, clear, straightforward and internally consistent;
e. Provide clear direction for resolution of regulatory conflict;
f. Be enforceable, efficiently administered and provide appropriate incentives
and penalties;
g. Be consistently and effectively enforced;
h. Create public and private benefits worth their cost;
i. Be coordinated with timely provision of necessary public facilities and
services;
j. Encourage creativity and diversity in meeting county goals and policies;
k. Be coordinated with cities, special purpose districts and other public
agencies to promote compatible development standards throughout King
County;
I. Be responsive, understandable and accessible to the public;
m. Provide effective public notice and reasonable opportunities for the public
(especially those directly affected) to be heard and to influence decisions;
n. Avoid intruding on activities involving constitutionally protected freedoms
of speech, petition, expression, assembly, association and economic
competition, except when essential to protect public health, safety and
welfare (and then the restriction should be no broader than necessary);
o. Treat all members of the public equally irregardless of race, culture or class
and base regulatory decisions wholly on the applicable criteria and code
requirements;
p. Make development requirements readily accessible to the public through
up-to-date codes, technical assistance materials and other relevant
documents; and
q. Provide for relief from existing regulations when they would deprive a
property of uses allowed to similar properties with the same zoning or
environmental or other constraints, and when such relief would neither
endanger public health and safety nor conflict with adopted use policies.
This policy is not intended for relief from rules governing the subdividing of
land.
9-1 September 2004
I. land Use Designations and Zoning ClasSilicationsJCode
The application of zoning classifications on specific properties is the first step towards
implementing the land use designations of the comprehensive pjan. Boundaries between different
zone classifications may follow property lines, natural features or other dividing lines such as roads.
A land use designation is implemented by one or more specific zone classification, as indicated on
the table below:
Comorehensive Plan Land Uses Zonina*
Unincorporated Activity Center R-12, R-18, R-24, R-48, RB (not allowed in White
Center\, NB, CB, 0, I
Communitv Business Center NB, CB, 0, R-12, R-18, R-24, R-48
Neiahborhood Business Center NB, 0, R-12, R-18, R-24, R-48
Commercial Outside of Centers NB, CB, RB, 0, I -this is the range of existing zoning in
nlace when the comorehensive olan was adooted
Urban Planned Development R-1, R-4, R-6, R-8, R-12, R-18,
R-24, R-48, NB, CB, RB, 0, I
Urban Residential, Hiah R-18, R-24, R-48
Urban Residential, Medium R-4, R-6, R-8, R-12
Urban Residential, Low R-1
Rural City Urban Growth Area UR I, RB -These two zones were in place in the North
Bend UGA when the comprehensive plan was adopted
in 1994.
Rural Town R-1, R-4, R-6, R-8, R-12, R-18,
R-24, R-48. NB, CB, RB, 0, I
Rural Neiahborhood NB
Rural Residential RA-2.5, RA-5, RA-10, RA-20
Industrial I
Forestrv F,M
Aariculture A
Minina M
GreenbelVUrban Seoarator R-1
Kina Countv Owned Ooen Scace/Recreation All zones
Other Parks/Wilderness All zones
• This is the range of zoning that may be allowed within each comprehensive plan land use designations based on
comprehensive plan and subarea p!an policies. Actual zoning on a specific property is determined through the area-wide
zoning process or through a quasi-judicial rezone application.
Zoning Designations
A Agricultural (10 or 35 acre minimum lot area)
F Forest (80 acre minimum lot area)
M Mineral
RA Rural Area (2.5-acre, 5-acre, 10-acre or 20-acre minimum density)
UR Urban Reserve
R Urban Residential (base density in dwelling units per acre)
NB Neighborhood Business
CB Community Business
RB Regional Business
0 Office
I Industrial
September 2004 9-2
The Zoning Code (Title 21 A) establishes precise rules for each zoning classification such as
permitted residential densities and activities or allowed commercial and industrial development
activities, and striving for separation between incompatible uses. This code includes standards
relative to bulk (i.e. lot size and coverage, building heights and setbacks, landscape standards).
1-102 The King County Zoning Code's zone classifications and development
standards and the official zoning maps shall be consistent with the
comprehensive plan and functional plans.
9-3 September 2004
II. lltller lmnle:menting ling Coun11 Code.s
In addition to the Zoning Code, King County regulates land development and construction based
on the comprehensive pjan through a variety of technical code standards resulting in permits and
approvals for specific projects.
In terms of land use regulation, the most important of these other implementing codes are Land
Segregation (K.C.C. Title 19A) and Shoreline Management (K.C.C. Title 25). The Land
Segregation code regulates division of a parcel of land into smaller lots for transfer of ownership.
The Shoreline Management code regulates the issuance of substantial development permits for
lands abutting waters governed by the Washington State Shoreline Management Act.
Other development approvals include commercial or industrial construction permits. Review of land
segregation, substantial development permits and other development proposals are key parts of the
development process for making sure facilities and services to support potential development are
adequate and for evaluating environmental impacts.
1-103 When needed infrastructure and facilities are not available in a timely
manner, development approvals shall either be denied or divided into
phases, or the project proponents should provide the needed facilities and
infrastructure to address impacts directly attributable to their project, or as
may be provided by the proponent on a voluntary basis.
1-104 King County's permitting systems should provide for expeditious review of
projects consistent with zoning and adopted policies.
1-105 Subdivision, short subdivision and other development approvals, including
those requiring detailed environmental review under the State Environmental
Policy Act (SEPA) shall be reviewed for consistency with the comprehensive
Qian, zoning, community, subarea and neighborhood plans, functional plans
and capital improvement programs.
1-106 King County shall enforce its land use and environmental regulations by
pursuing code enforcement complaints, and providing oversight during the
process of site development on all sites for which it issues permits.
1-107 King County shall develop, as a part of the buildable lands analysis, a zoning
yield and housing production monitoring program to determine whether
housing capacity is being lost in the context of compliance with the
Endangered Species Act, and shall propose revisions to the countywide
planning policies to implement such a program.
September 2004 9-4
111. Incentives
To ensure that the vision, goals, objectives, and policies of this plan become a reality, it will
require adjusting policy and budget priorities by King County government. It will also require
individuals to reconsider their daily decisions and choices relating to the management or
development of their lands, as well as the decisions and choices of large scale public/private
partnerships during the development of major projects will be critical factors contributing to the
effective implementation of this plan. Incentives, like the TDC Program, must encourage the types
of growth and development patterns desired by King County and its residents.
1-201 King County should develop incentives for the Urban Growth Area which
encourage the development industry to provide a broad range of housing and
business space. Incentives could include:
a. Identification of geographic areas with infill opportunities, granting them
budget priority status and subjecting new development in these areas to
more flexible standards;
b. Density bonuses for site designs which provide public benefits (for
example, grid roads that connect with other developments and limit
impacts on arterials);
c. Incentives which lower financial development risk;
d. Joint development opportunities at county-owned or operated facilities,
utilization of air rights on county-owned or operated facilities, and the
establishment of transit-supportive design guidelines; and
e. County capital improvement funding for public urban amenities including
transportation, parks, open space, cultural and other facilities for cities
participating in the King County Transfer of Development Rights
Program.
9-5 September 2004
2004 Comprehensive Plan
Glossarv
Glossarv
Active Recreation Site
Active recreation sites recognize a higher level of public use, and will require developed areas for
organized or intense recreation. Active recreation site includes both the active recreation uses
and all necessary support services and facilities.
Adaptive management
Adaptive management is a systematic approach for continually improving management policies
and practices by learning from the outcomes of operational programs.
Agricultural Production Districts (APD)
The Growth Management Act requires cities and counties to designate, where appropriate,
agricultural lands that are not characterized by urban growth and that have long-term significance
for the commercial production of food or other agricultural products. The comprehensive plan
designates Agricultural Production Districts where the principal land use should be agriculture.
Lands within Agricultural Production Districts should remain in parcels large enough for
commercial agriculture. (See Chapter Three, Rural Legacy and Natural Resource Lands.)
Annexation
This is the process of adding or incorporating an area into a city's jurisdiction.
Arterial Functional Classification
Arterial functional classification is the designation of King County arterials into groups or classes
according to the type of service they are intended to provide. A basic tenet to this process is that
individual roads do not serve travel in any substantial way, but most travel involves movement
through a network of roads. Functional classification helps to define the part that any individual
road will play in serving the flow of traffic through the road system.
Beneficial Uses
"Beneficial uses" include uses of water resources that provide a benefit to the public, including,
but not limited to, fish and wildlife habitat, fishing, swimming, transportation, recreation, water
supply, flood control, water quality control, and aesthetic enjoyment.
Best Management Practices (BMPs)
These are defined by the Washington State Department of Ecology as physical, structural, and/or
managerial practices that, when use.d singly, or in combination, prevent or reduce pollution of
water. The types of BMPs are source control, runoff treatment, and stream bank erosion control.
Capital Improvement Program (CIP)
The 1994-1999 Adopted Capital Improvement Program budget allocates funds from various
revenue sources to improve cultural and recreational opportunities for King County citizens, build
needed roadways, protect our investment in existing buildings, protect the health of our citizens,
enhance the management of natural resources, and provide necessary capital resources for our
law, safety, and justice system.
Clustering
Clustering means developing a subdivision that reduces the individual lot areas to create
permanent open space or a reserve for future development while it maintains the zoned
residential density.
G-1 September 2004
Community Business Centers
These are primarily retail developments designed to serve a nearby market area of 15,000 to
40,000 people. (See Chapter Two, Urban Communities.)
Comprehensive Plan
The Growth Management Act requires certain cities and counties of the state to adopt
comprehensive land use plans. A comprehensive plan is a generalized, coordinated land use
policy statement of the governing body of a county or city that is adopted pursuant to the Growth
Management Act. A comprehensive plan consists of a map or maps, and descriptive text
covering objectives, principles, and standards used to develop the comprehensive plan. Each
comprehensive plan includes a plan, scheme or design for land use, housing, capital facilities,
utilities, rural areas, and transportation. Optional components include elements relating to
conservation, solar energy, recreation, and subarea plans.
Concurrency Management System
The Growth Management Act requires jurisdictions to adopt and enforce ordinances' which
prohibit development approval if the development causes the level of service on a transportation
facility to decline below the standards adopted in the comprehensive plan, unless transportation
improvements or strategies to accommodate the impacts of development are made "concurrent"
with the development. Concurrent with development means that transportation improvements or
strategies are in place at the time of development or that financial commitment is made to
complete the improvements or strategies within six years. The Concurrency Management
System of King County establishes a process to manage new development based on
transportation impacts on levels-of-service and the concurrency of needed improvements or
actions. (See Chapter Six, Transportation).
Coordinated Water System Plans
Four Critical Water Supply Service Areas have been designated in King County in accordance
with the Public Water System Coordinated Act of 1977 (chapter 70.116 RCW): East King County,
Skyway, South King County, and Vashon Island. The Coordinated Water System Plan for each
area provides an assessment of water supply and a program to meet future demand. Planning
areas, within which a water purveyor is obligated to provide service consistent with county land
use plans and regulations, were assigned for major purveyors.
Countywide Planning Policies (CPP)
The Growth Management Act requires that counties, as regional governments within their
boundaries, prepare countywide planning policies which establish a countywide framework from
which county and city comprehensive plans are to be developed and adopted. This framework is
to ensure that city and county comprehensive plans are consistent. The "King County
Countywide Planning Policies" were developed and recommended by the Growth Management
Planning Council and are to serve as a blueprint for how King County and its cities should grow
over the next 20 years. The Metropolitan King County Council adopted these policies in 1992.
Since this time, amendments called "Phase 11 Countywide Planning Policies" have been made to
the sections pertaining to affordable housing, economic development and rural character. The
County Council has adopted these Phase II amendments. (See Chapter One, Regional
Planning.)
Critical Areas
The Growth Management Act requires cities and counties to designate, where appropriate, critical
areas which include: 1) wetlands, 2) areas with a critical recharging effect on aquifers used for
potable water, 3) fish and wildlife habitat conservation areas, 4) frequently flooded areas, and 5)
geologically hazardous areas. (See Chapter Four, Environment for King County's designation of
critical areas.)
September 2004 G-2
Critical Habitat
Specific areas which possess physical or biological features which are essential to the
conservation of a listed species.
Cultural Resources
Cultural resources include performing and visual arts events, programs and facilities; public art;
heritage events, programs and facilities; and historic properties.
Deficiency
Deficiency in a comprehensive plan or development regulation refers to the absence of required
or potentially desirable contents of a comprehensive plan or development regulation.
Density
The quantity of structures or buildings per unit area. Typically expressed as housing units per
acre or square mile.
Density Incentives/Bonuses
Density incentives, or density bonuses, are programs allowing for additional dwelling units above
the number permitted on a site by zoning (sometimes referred to as "base density") in exchange
for public benefits provided by the developer. King County has incorporated use of density
incentives with standard urban subdivision, mobile home park, and multifamily development
projects. (King County Code, Title 21 A)
Development
An area that is developed as a tract of land with built structures.
Docket
A list of suggested changes to a comprehensive plan or development regulations maintained by
the department.
Docket Process, The
The docket process specifies that dockets are not just to note deficiencies, but also to suggest
changes and make written comments. These suggested changes are reviewed by the county
and made available for review by the public. Information provided to the public will include the
county's response. An Internet docket process is available and can be found at:
http://www.metrokc.gov/ddes/compplan/.
Docketing
Docketing means compiling and maintaining a list of suggested changes to the comprehensive
plan or development regulations in a manner that will ensure such suggested changes will be
considered by the county and will be available for review by the public.
Drainage Basin
A drainage basin, like a watershed, is an area that drains to a common outlet or an identifiable
water body such as a river, stream, lake or wetland. In King County, 72 drainage basins are
contained within six major watersheds. These drainage basins in turn contain numerous
individual water bodies with small drainages.
Ecological Function
An ecological function refers to physical, chemical, and biological processes or attributes at some
level of biological organization. For example, the ecological functions of wetlands includes food
chain support, water quality maintenance, flood storage, and wildlife habitat.
G-3 September 2004
Emissions Trading
Emissions trading means the transfer in ownership of emission reductions. Emission trading
occurs when a source of air pollution reduces its emissions and then transfers ownership of the
emission reduction to another party. Markets for emission reductions can be created by
regulation (the market for sulfur dioxide allowances for example) or voluntarily (the current market
for greenhouse gases).
Endangered Species
Endangered Species means any species which is in danger of extinction throughout all or a
significant portion of its range and which has been designated as such in regulations issued by
the U.S. Fish and Wildlife Service or the Washington State Department of Fish and Wildlife.
Endangered Species Act (ESA)
An act adopted by U.S. Congress in 1973 whose purpose is to provide a means whereby
ecosystems upon which endangered and threatened species depend may be conserved and to
provide a program for the conservation for such endangered and threatened species.
Enhance
Enhance means to increase one or more of the functions or values that an ecosystem or
environmental feature possesses. An improvement in a functional attribute or value. (See
Chapter Four, Environment).
Environmentally Sensitive Areas
Coal mine, erosion, flood, landslide, seismic, steep slope and volcanic hazard areas, and
streams, wetlands and protection buffers constitute environmentally sensitive areas.
Existing transportation needs
Existing transportation needs are associated with households and businesses which are in
existence at the time of plan adoption.
Fair Housing Ordinance
King County's Fair Housing Ordinance prohibits housing discrimination against persons on the
basis of race, color, religion, national origin, age, sex, marital status, parental status, use of
Section 8 subsidy, sexual orientation, disability or the use of a trained guide dog.
Family-Wage Jobs
Family-wage jobs which are capable of supporting a family. For the purposes of this plan, the
term means jobs which pay more than the average annual wage for King County in a given year.
Fish and Wildlife Habitat Conservation Areas
Designation of Fish and Wildlife Habitat Conservation Areas is required by the Growth
Management Act. This Comprehensive Plan designates the following as such areas: 1) areas
with which endangered, threatened, and sensitive species have a primary association; 2) habitats
and species of local importance; 3) commercial and recreational shellfish areas; 4) kelp and eel
grass beds; 5) herring and smelt spawning areas; 6) naturally occurring ponds under 20 acres
and their submerged aquatic beds that provide fish or wildlife habitat; 7) waters of the state; 8)
lakes, ponds, streams, and rivers planted with game fish by a governmental or tribal entity; and 9)
state natural area preserves and natural resource conservation areas.
Flood Hazard Reduction Plan
The King County Flood Hazard Reduction Plan contains policies and program and project
recommendations that guide floodplains use and development throughout King County.
September 2004 G-4
Floodplain
The areas of land adjacent to lakes, rivers, and streams that are subject to periodic flooding.
Floodplains are designated based on the predicted frequency of flooding for a particular area.
For example, a 1 OD-year floodplain is a land area that has a one percent probability of
experiencing flooding in any given year.
Forest Production Districts (FPO}
The Growth Management Act requires cities and counties to designate, where appropriate, forest
lands that are not characterized by urban growth and that have long-term significance for the
commercial production of timber. The Comprehensive Plan designates Forest Product"1on
Districts where the primary use should be commercial forestry. Lands within the Forest
Production District shall remain in large parcels and in ownership conducive to forestry. (See
Chapter Three, Rural Legacy and Natural Resource Lands).
Fully Contained Community (FCC}
A site-specific development project consisting of conceptual site plan(s), development standards,
processing and other elements. It is also consistent with the criteria provided in RCW 36. ?OA.350
which states that FCCs should be located outside of the initially designated Urban Growth Area.
Functional Classification
See "Arterial Functional Classification"
Functional Planning
Functional plans are detailed plans for facilities and services and action plans and programs for
other governmental activities. Some functional plans are operational or programmatic, which
means they guide daily management decisions. Others include specific details of facility design
and location and must be consistent with the Comprehensive Plan and development regulations.
Functional plans are prepared by King County, independent special purpose districts or other
public and private agencies. (See Chapter Nine, Implementation)
Global Warming
Global warming is an increase in worldwide atmospheric temperature.
Groundwater Management Plans
King County has five Groundwater Management Areas (GWMA) for which citizens and technical
experts are addressing groundwater issues. For each GWMA, a Groundwater Management Plan
(GWMP) has been developed per chapter 173-100 WAC (chapter 90.44 RCW). Each GWMP
describes the area's groundwater resource, contains a detailed exploration of groundwater
protection issues, and proposes solutions to perceived threats. These Plans identify Sensitive
Aquifer Areas to receive a special level of protection.
Growth Management Act (GMA)
In 1990, the Washington State Legislature passed the State Growth Management Act (ESHB
2929). The Act calls for urban counties and cities in the state to develop comprehensive plans to
guide growth management decisions for at least the next decade. Amendments to the Act in
1991 require that counties, working with the cities within their boundaries, develop Countywide
Planning Policies to provide a common vision of the future to serve as the framework for all
comprehensive plans throughout the county. (See Chapter One, Regional Planning)
Growth Management Planning Council (GMPC}
The GMPC, which was established by an interlocal agreement, is a 15-member council of elected
officials from Seattle, suburban cities and King County. The GMPC has been responsible for the
preparation and recommendation of the Countywide Planning Policies to the Metropolitan King
County Council, which then adopts the policies and sends them to the cities for ratification.
G-5 September 2004
Habitat
Habitat is the area where wildlife normally lives and grows. Habitat components include food,
water, cover (security, breeding, thermal) and space.
Habitat Network
Habitat network is a system of fish and wildlife habitat where connections between large habitat
blocks and open spaces are necessary for the support of fish and wildlife through their life cycles.
Historic Properties
Historic properties include historic buildings, sites, objects, districts and landscapes, prehistoric
and historic archaeological resources, and traditional cultural places.
Historic Property, Significant
Significant historic properties are those properties that meet the criteria for designation as County
landmarks and/or listing in the National Register of Historic Places.
Impervious surface
A hard surface area which either prevents or retards the entry of water into the soil mantle as
under natural conditions prior to development; and/or a hard surface area which causes water to
run off the surface in greater quantities or at an increased rate of flow from the flow present under
natural conditions prior to development. Common impervious surfaces include, but are not
limited to, roof tops, walkways, patios, driveways, parking lots and gravel roads.
Incorporated Areas
Incorporated areas are those areas that exist within a city or a city's jurisdiction. King County
contains 39 whole incorporated cities and parts of two others.
Infill
Infill means development or redevelopment on small properties or groups of properties within
existing built-up areas.
Initial Project Needs
Road improvement projects that are needed to meet the impacts of a specific development are
initial project needs. They must be concurrent with the development.
King County Open Space System
This is a system of linked publicly owned regional open space corridors of greenways and
waterways along the major river systems, shorelines and the Mountain-to-Sound Greenway.
(See Chapter Five, Preserving and Enriching the Community)
Land Use Map
The official land use map for the Comprehensive Plan that designates the general location and
extent of the uses of land for agriculture, timber production, housing, commerce, industry,
recreation, open spaces, public utilities, public facilities, and other land uses as required by the
Growth Management Act. The Land Use Map is not included in the Plan because it is very large.
It is available for review at the Department of Development and Environmental Services and at
the Clerk of the King County Council. A smaller representation of the Land Use Map is included
in the Comprehensive Plan.
Level-of-Service -Transportation
Transportation level-of-service is a qualitative measure, graded A through F, describing the
operational conditions of the County's transportation system (assessing both design capacity and
actual traffic volumes by corridor) as experienced by travelers and which is determined by using
the Transportation Adequacy Measure (TAM) methodology.
September 2004 G-6
Locally Significant Resource Areas (LSRAs)
LSRAs contribute to the aquatic resources within a specific basin, when compared to aquatic and
terrestrial systems of similar size and structure elsewhere in the basin. They also provide
wetland and stream habitat that is important for wildlife and salmonid diversity and abundance
within the basin. (See Chapter Four, Environment)
Low-Impact Development
Low-impact development (LID) is a new approach to land development which works to match a
site's natural hydrologic function by protecting native vegetation and soils, reducing impervious
surface and managing stormwater at the source.
Master Planned Resorts
RCW 36. ?OA.040 defines Master Planned Resorts as a self-contained and fully integrated
planned unit development, in a setting of significant natural amenities, with primary focus on
destination resort facilities consisting of short-term visitor accommodations associated with a
range of developed on-site indoor or outdoor recreation facilities. A master planned resort may
include other residential uses within its boundaries, but only if the residential uses are integrated
into and support the on-site recreational nature of the resort.
May
See definition for "shall"
Median Household Income
The median divides all households into two equal groups, one having income above the median
and the other having income below the median.
Mineral Resource Sites
The Growth Management Act requires cities and counties to designate, where appropriate,
mineral resource lands that are not already characterized by urban growth and that have long-
term significance for the extraction of minerals. The Comprehensive Plan designates as Mineral
Resource Sites existing, approved mining sites, and also designates as Potential Mineral
Resource Sites properties on which King County expects some future mines may be located.
(See Chapter Three, Rural Legacy and Natural Resource Lands)
Mitigation Bank
A mitigation bank is a property approved by the appropriate county, state and federal agencies for
restoration, creation, or enhancement to compensate for adverse impacts to wetlands caused by
the development of public agency facilities and utility facilities.
Mitigation Payment System
This system establishes a requirement that new growth and development pay a proportionate
share of the cost of supporting needed transportation improvements. The proportionate share is
that portion of the cost of transportation facil',ty improvement that is related to the service
demands and needs of the new development. (See Chapter Six, Transportation)
Mixed Use
This term refers to a development with combined commercial and residential uses.
Mode Split
Mode split is the percentage of all trips using non-single occupant vehicular forms or modes of
travel. Modes of travel include single-occupant vehicles, transit, carpooling, bicycling, walking,
and other modes.
Multifamily
Multifamily housing structures are those with more than one unit. Multifamily housing includes
duplexes, apartments and condominiums.
G-7 September2004
Natural Resource Lands
The Growth Management Act requires cities and counties to designate natural resource lands
which include the following: 1) agricultural lands that have long-term significance for the
commercial production of food or other agricultural products; 2) forest lands that have long-term
significance for the commercial production of timber; and 3) mineral resource lands that have
long-term significance for the extraction of minerals. The Comprehensive Plan designates
Agricultural Production Districts, Forest Production Districts, and Mineral Resource Sites. (See
Chapter Three, Rural Legacy and Natural Resource Lands)
Natural Sites
Natural sites recognize areas valued for their natural character. They may not be completely
natural and undisturbed, but may be important in preserving rare or vanishing flora, fauna,
geological sites or features of scientific, traditional, cultural, and/or educational value.
Development and use will focus on keeping the environment in a nearly undeveloped state.
There may be little or limited public access to these sites.
Neighborhood Business Centers
These are shopping areas offering convenience goods and services to local residents. They
primarily contain retail stores and offices. (See Chapter Two, Urban Communities)
Neighborhood Plan
Small-scale plans meant to provide detailed land use plans for neighborhoods. (See also
Subarea Planning)
New Growth
New growth is growth that occurs subsequent to pipeline development for which no application is
currently pending review/approval in the King County permitting process, but which is forecasted
to occur over the next 20 years in this Comprehensive Plan.
Nondegradation
Nondegradation means to prevent the decline to a lower state, to keep from reducing the
complexity, functions, or integrity of ecological processes or values.
Nonmotorized Transportation
This refers to pedestrian, bicycle, and equestrian travel, and the facilities needed to make it safe
and convenient.
Non-point Pollution
Non-point pollution is pollution which enters any waters of the State from any dispersed land-
based or water-based activities, including but not limited to atmosphere disposition, surface water
runoff from agricultural lands, urban areas, or forest lands, subsurface or underground sources,
or discharges from boats or marine vessels.
Open Space
The Growth Management Act requires cities and counties to identify open space corridors within
and between urban growth areas which include lands useful for recreation, wildlife habitat, trails,
and connection of critical areas. Open space lands, as designated by the Comprehensive Plan,
include federal, state and locally owned parks and wilderness areas, developed parks and areas
left in a natural state so they can sustain sensitive ecosystems, community identity and aesthetics
and links between important environmental or recreational resources. (See Chapter Five,
Preserving and Enriching Our Community)
Particulate Matter
Particulate matter is solid or aerosol particles dispersed in the air including dust, soot, and oil.
The major sources are industrial activities, fugitive road dust, motor vehicle emissions, and wood
smoke.
September 2004 G·8
Passive Recreation Site
Passive recreation sites require a lower level of development and provide areas for informal, self-
directed activities for individuals and groups.
Pervious surface
A surface area which allows the entry of water into the soil mantle, as under natural conditions
prior to development.
Pipeline Development
These are land use development applications, whether vested or unvested, that were submitted
prior to adoption of King County Comprehensive Plan and are pending review/approval in the
permitting process.
Pipeline transportation needs
Pipeline transportation needs are associated with growth that is pending through the County's
development review process.
Point Pollution
Point pollution is pollution that enters any waters of the State from an identifiable source such as
a pipe.
Potential Annexation Area (PAA)
A Potential Annexation Area is an area in unincorporated King County adjacent to a city that is
expected to annex to the city and to which that city will be expected to provide services and
utilities within the next two decades. (See Chapter Two, Urban Communities)
Protect
Protect means to keep from harm, attack, injury, or destruction; to maintain the integrity of,
especially through environmental care.
Public Benefit Rating System
This is a current use taxation program whereby the reduction in property taxes is determined
using a scoring system related to the numbers and quality of open space resources located on all
or portions of the property.
Puget Sound
Puget Sound is an estuary-a semi-enclosed, glacial fjord where salt water from the ocean is
mixed with fresh water. Puget Sound is bordered by about 1,300 miles of shoreline with a mix of
beaches, bluffs, deltas, mudflats, kelp forests and eelgrass meadows. Approximately 100 miles
of this saltwater shoreline lie within King County. King County's immediate responsibilities
include those portions of Puget Sound which lie within the County, roughly between Point Wells
to the north and Dumas Bay to the south. King County shares responsibility for the health of the
main basin of Puget Sound with its neighbors --Pierce County, Kitsap County, and Snohomish
County.
Puget Sound Regional Council (PSRC)
The PSRC is the designated metropolitan planning organization for our area and is responsible
for regional growth management and transportation planning in the four county region which
includes King, Pierce, Snohomish and Kitsap Counties. PSRC's General Assembly includes
mayors, county executives, and council commission members from the four counties. The
Council also includes as members the ports of Everett, Seattle and Tacoma and the State
Department of Transportation and Transportation Commission. The PSRC prepared Multi-county
Planning Policies for the four-county region.
G-9 September 2004
Regionally Significant Resource Area (RSRA)
RSRAs are those portions of watersheds that contribute to the resource base of the entire Puget
Sound region by virtue of exceptional species and habitat diversity and abundance when
compared to aquatic and terrestrial systems of similar size and structure elsewhere in the region.
RSRAs may also support rare, threatened or endangered species or communities. (See Chapter
Four, Environment)
Regional Wastewater Services Plan (RWSP)
In 1999, King County adopted the Regional Wastewater Services Plan, guiding the development
of new facilities to manage wastewater into the future. The RWSP addresses four areas:
wastewater treatment facilities, combined sewer overflow control, wastewater reuse, and bio-
solids management. The RWSP outlines where new facilities will be built, the types of technology
to be used and the future of reclaimed water and bio-solids. Short-term needs through 2006 are
specified, and long-term alternatives to the current Metro system are identified.
Restore
Restore means to return land and water resources from a disturbed or totally altered condition to
an approximation of their condition prior to disturbance or alteration. Restoration projects are
conducted by public agencies through capital improvement projects and by developers as a
means to mitigate adverse impacts of their proposals. (Restoration of land is not required of
developers when they protect land and water resources according to King County regulation.)
(See Chapter Four, Environment)
Rezones
Rezoning is the term that refers to the process of individual requests and applications to change
the zoning classification of land.
Riparian
Pertains to the banks of rivers and streams, and also sometimes wetlands, tidewater and lakes.
Rural Area (See also Rural Zoning)
The Growth Management Act requires that counties designate a rural area in order to conserve
the rural character and quality of the existing rural lands in Washington. King County's Rural
Area contains very low-density residential development, commercial and industrial development,
farms, forests, watersheds crucial for both fisheries and flood control, mining areas, small cities
and towns, historic sites and buildings, archaeological sites and regionally important recreation
areas. (See Chapter Three, Rural Legacy and Natural Resource Lands)
Rural Character
Rural character refers to the pattern of land use and development established by a county in the
rural element of its comprehensive plan:
(a) In which open space, the natural landscape, and vegetation predominate over the built
environment;
(b) That foster traditional rural lifestyles, rural-based economies, and opportunities to both live
and work in rural areas;
(c) That provide visual landscapes that are traditionally found in rural areas and communities;
(d) That are compatible with the use of the land by wildlife and for fish and wildlife habitat;
(e) That reduce the inappropriate conversion of undeveloped land into sprawling, low-density
development;
(f) That generally do not require the extension of urban governmental services; and
(g) That are consistent with the protection of natural surface water flows and groundwater and
surface water recharge and discharge areas.
September 2004 G·10
Rural Cities
King County's rural cities are incorporated areas within the Rural Area whose local governments
are involved in the region's planning processes on an equal legal basis with the suburban cities
and Seattle. The incorporated rural cities are Black Diamond, Carnation, Duvall, Enumclaw,
North Bend, Skykomish and Snoqualmie. (See Chapter Three, Rural Legacy and Natural
Resource Lands)
Rural Growth
Rural Growth refers to residential, commercial, and industrial growth that is scaled to be
compatible with, and mainta·,ns the traditional character of the Rural Area. Rural growth typically
does not require urban governmental services except in the case of some rural towns and to
protect the environment as provided in this Comprehensive Plan. The basic elements of "Rural
Character," as defined by the King County Countywide Planning Policies, are natural features,
resource-based industries, rural towns, rural neighborhoods, rural infrastructure and services,
open space system, rural housing, rural economy, and rural cities.
Rural Neighborhoods
Rural neighborhoods are small commercial developments, or in some cases, historic towns or
buildings, that are too small to provide more than convenience shopping and services to
surrounding residents. They generally do not have services such as water supply or sewage
disposal systems any different from those serving surrounding rural residential development.
(See Chapter Three, Rural Legacy and Natural Resource Lands)
Rural Towns
Rural towns are unincorporated towns governed directly by King County. They provide a focal
point for community groups such as chambers of commerce or community councils to participate
in public affairs. The purposes of rural town designations within the Comprehensive Plan are to
recognize existing concentrations of higher density and economic activity in rural areas and to
allow modest growth of residential and economic uses to keep them economically viable into the
future. (See Chapter Three, Rural Legacy and Natural Resource Lands)
Rural Zoning
The rural zone is meant to provide an area-wide, long-term, rural character and to minimize land
use conflicts with nearby agricultural, forest or mineral extraction production districts. These
purposes are accomplished by: 1) limiting residential densities and permitted uses to those that
are compatible with rural character and nearby resource production districts and are able to be
adequately supported by rural service levels; 2) allowing small scale farming and forestry
activities and tourism and recreation uses which can be supported by rural service levels and
which are compatible with rural character; and
3) increasing required setbacks to minimize conflicts with adjacent agriculture, forest or mineral
zones.
Salmonid
A member of the fish family Salmonidae. In King County, salmonid species include Chinook,
Coho, chum, sockeye, and pink salmon; cutthroat, rainbow, and brown trout and steelhead; Dolly
Varden, brook trout, char, kokanee, and whitefish.
Satellite System Management
When large water utilities oversee the operations of smaller water systems, not connected to their
own system, it is called satellite system management. The satellite system manager is hired by
the smaller system to operate and maintain the system in accordance with local, state and federal
health regulations.
G-11 September 2004
Sediment Transport
Sediment transport is the process of taking soil from one place and depositing it in another via the
flow of water. Deposition of the soil occurs when sediment in the water flow is more than the flow
can transport.
Sensitive Areas Map Folio
The folio displays the location of environmentally sensitive areas in unincorporated King County.
It identifies sensitive areas for wetlands, streams, flood hazards, erosion hazards, landslide
hazards, seismic hazards, and coal mine hazards.
Sensitive Species
Sensitive species means any species which is likely to become an endangered species within the
foreseeable future throughout all or significant portion of its range and which has been designated
as such in regulations issued by the U.S. Fish and Wildlife Service or the Washington State
Department of Fish and Wildlife.
Sewer Availability
Sewer availability means the presence of sewers now or within six years through extensions
included in adopted sewer comprehensive plans. In the case of Urban Planned Development, 1)
the capacity to intercept and treat waste water as evidenced by a King County approved sewer
system plan or a Metro utility plans, 2) a firm commitment to serve an area with sewer as
evidenced by either a sewer availability certificate, utility extension agreement, or an approved
sewer system plan and 3) a firm financial commitment to provide sewer, as evidenced by either a
capital improvement program or utility extension agreement.
Sewer Tightline
Tightlining of sewers means that a sewer line is designed and sized to only serve a particular
structure.
Shall
To guide King County, the use of the terms "shall," "will," "should," and "may" in policies
determine the level of discretion the County can exercise in making future and specific land use,
budget, development regulation and other decisions. "Shall" and "will" in a policy mean that it is
mandatory for the County to carry out the policy, even if a timeframe is not included. "Shall" and
"will" are imperative and nondiscretionary-the County must make decisions based on what the
policy says to do. "Should" in a policy provides noncompulsory guidance, and establishes that
the County has some discretion in making decisions. "May" in a policy means that it is in the
County's interest to carry out the policy, but the County has total discretion in making decisions.
Short Subdivisions
These are subdivisions in unincorporated King County that are limited to four lots or less (nine in
some cities), and are approved administratively by King County's Department of Development
and Environmental Services.
Should
Noncompulsory guidance; establishes that the County has some discretion in making decisions.
Significant Adverse Environmental Impact
Significant as used in State Environmental Policy Act means a reasonable likelihood of more than
a moderate adverse impact on the environment. Significance involves context and intensity and
does not lend itself to a formula or quantifiable text. The context may vary with the physical
setting. Intensity depends on the magnitude and duration of an impact. The severity of an impact
should be weighed along with the likelihood of its occurrence. An impact may be significant if its
chance of occurrence is not great, but the resulting environmental impact would be severe if it
occurred.
-September 2004 G-12
Single-Family
Single-family housing units are individual structures including conventional houses and mobile
homes.
Subarea Planning
This level of planning brings the policy direction of the comprehensive plan to a smaller
geographic area. Subarea plans are meant to provide detailed land use plans for local
geographic areas. These plans are meant to implement the King County Comprehensive Plan
and be consistent with the County's Comprehensive Plan's policies, development regulations,
and Land Use Map.
Subdivision
A subdivision is land that has been divided into legal lots, or is the process of dividing land into
lots.
Traditional Rural Development
In King County, traditional rural land uses could include, but are not limited to: low density
residential uses; small scale farming, forestry and mineral extraction; small, neighborhood
churches; feed and grain stores; the keeping of horses and livestock; cottage industries, crafts
and trades that support the residents of the rural area and/or the needs of the natural resource
production areas; and public and private facilities necessary to serve rural homes such as utility
installations or public schools. In general, the rural development pattern in King County has
historically been comprised of houses, barns, fences and cultivated fields, but natural features
and open spaces are the predominant visual image.
Transfer of Development Rights (TDR)
Transfer of development rights means the ability to transfer allowable density, in.the form of
permitted building lots or structures, from one property (the "sending site") to another (the
"receiving site") in conjunction with conservation of all or part of the sending site as open space or
working farm or forest. King County allows transfers of development rights as part of standard
subdivision, mobile home park and multifamily project review processes through its TOR
Program. (King County Code, Title 21A)
Transit Oriented Development (TOD)
A private or public/private real estate development project that creates, expands, maintains or
preserves a mixed-use community or neighborhood within walking distance of a transit center, or
stop, that is designed to encourage transit use and pedestrian activity. TOD projects support
transit by increasing the density of residents, shoppers, visitors or employees per acre. New
TOD projects are often coupled with an increase in transit service to the area.
Transportation Adequacy Measure (TAM)
The Transportation Adequacy Measure is the County's methodology for measuring the level-of-
service performance of its transportation system. Transportation Adequacy Measure is a
calculated index of the quality of transportation experienced by travelers. It is based on two
components; a system-wide average ratio of traffic volumes to traffic capacities; (the lower this
weighted average, the better the transportation adequacy) and the volume to capacity rates of
certain roads that are critical to system performance (critical links). The TAM applies to discrete
land areas (zones) in the County and is the basis for transportation level-of-service standards.
(See Chapter Six, Transportation)
Transportation Certificate of Concurrency
An official notice given to a property owner by the Department of Transportation or its successor
that indicates whether there is capacity on the transportation system to accommodate new
growth. A Transportation Certificate of Concurrency is required to show that adequate
transportation facilities are available to service growth as part of the development review process.
G-13 September 2004
Transportation Demand Management (TDM)
TOM is a strategy for the reduction of automobile trips, particularly trips taken in single-occupant
vehicles. TOM encourages public transportation over automobile use and specifically refers to
policies, programs and actions implemented to increase the use of high-occupancy vehicles
(public transit, car-pooling and van-pooling) and spread travel to less congested time periods
through alternative work hour programs (See Chapter Six, Transportation).
Transportation Facilities and Services
These are the physical assets of the transportation system that are used to provide mobility.
They include roads, transit, bridges, traffic signals, ramps, buses, bus garages, park and ride lots
and passenger shelters.
Transportation needs for new growth
Transportation needs for new growth are associated with growth that has been planned for 2012
in this Comprehensive Plan.
Transportation Needs Report (TNR)
The TNR is a comprehensive list of recommended County transportation needs through the year
2012 needed to implement the land use element. It includes transportation needs for
unincorporated King County, and some city, state, and adjacent County projects. It does not
include transit service or capital needs. (See Chapter Six, Transportation)
Unemployment Rate
The unemployment rate is the percentage of the civilian labor force that is unemployed and
actively seeking employment.
Unincorporated Activity Centers
Unincorporated Activity Centers are the primary locations for commercial and industrial
development in urban unincorporated King County. Currently, White Center is the only
designated Unincorporated Activity Center, as other such centers are now parts of cities. (See
Chapter Two, Urban Communities)
Unincorporated Areas
Unincorporated areas are those areas outside any city and under King County's jurisdiction.
Unique Wetland
The term unique wetland refers to bogs and fens which have unusual and sensitive water
chemistries.
Urban Centers
These are centers of concentrated employment and housing located within the Urban Growth
Area designated by the Phase II Countywide Planning Policies. Urban Centers are to be serviced
directly by high-capacity transit and·are to contain a wide variety of land uses, including retail,
recreational, cultural and public facilities, parks and open spaces. Urban Centers include the
central business districts of Federal Way, Bellevue, Seattle, Renton, SeaTac, Kent, Redmond
and Tukwila. Other Urban Centers are Seattle Center, Seattle First Hill/Capitol Hill, Seattle
University District and Seattle Northgate. (See Chapter Two, Urban Communities)
Urban Growth
Urban growth refers to residential, commercial and industrial growth that makes intensive use of
land for the location of buildings, structures and impermeable surfaces to such a degree as to be
incompatible with the primary use of such land for the production of food, other agricultural
products, or fiber, or the extraction of mineral resources. Urban growth typically requires urban
governmental services. "Characterized by urban growth" refers to land having urban growth
located on it, or to land located in relationship to an area with urban growth.
September 2004 G-14
Urban Growth Area (UGA)
The Growth Management Act requires King County's Comprehensive Plan to designate an Urban
Growth Area, where most future urban growth and development is to occur to limit urban sprawl,
enhance open space, protect rural areas and more efficiently use human services, transportation
and utilities. The Comprehensive Plan designates an UGA which includes areas and densities
sufficient to permit the urban growth that is projected to occur in the County for the succeeding
20-year period. (See Chapter One, Regional Planning and Chapter Two, Urban Communities)
Urban Growth Target
The Growth Management Act and the Countywide Planning Policies require King County and its
cities to plan for a 20-year population and employment growth target for each jurisdiction, based
on designation of the Urban Growth Area, Urban Centers and the criteria of the Countywide
Planning Policies. (See Chapter Two, Urban Communities)
Urban Planned Developments (UPD)
Urban Plan Developments are site specific projects consisting of conceptual site plans,
development stands, processing and other elements.
Urban Separator
Urban separators are areas planned for permanent low-residential density within the Urban
Growth Area. Urban separators protect adjacent resource land, environmentally sensitive areas,
or rural areas and create open space corridors within and between urban areas which provide
environmental, visual, recreations and wildlife benefits.
Utilities Technical Review Committee (UTRC)
This is an interdepartmental committee with responsibility for ensuring that water and sewer plans
comply with County and State health requirements and County land use policies. The committee
reviews the plans of all water and sewer utilities that operate in unincorporated King County and
then recommends the plans to King County Executive and the Metropolitan King County Council
for approval.
Water Availability
Water availability means the presence of a water source with applicable water rights that can
serve the projected demand through the year 2000, as shown by adopted water comprehensive
plans. In the case of Urban Planned Developments, water availability is defined as 1) presence
of a water source with water rights that can serve the projected average daily demand through
the year 2000, 2) a firm commitment to serve an area with water, as evidenced by either a water
availability certificate, utility extension agreement or a King County approved water system plan
and 3) a firm financial commitment to provide water, as evidenced by either a capital
improvement plan or utility extension agreement.
Water Reuse
Water reuse or wastewater reclamation involves using treated wastewater in place of drinking
water for commercial irrigation and industrial processes. Also referred to as wastewater reuse.
Water Supply Availability
Water supply availability is the presence of a water source with applicable water rights that can
serve the projected demand through the year 2000, as shown by adopted water comprehensive
plans.
Water System Classifications
A public water system is defined as any system that has more than one connection. A well
serving one house is a private system. Group A water systems have fifteen or more service
connections. Group B water systems have two through fourteen service connections.
G-15 September 2004
Watershed
A watershed, like a drainage basin, is an area that drains to a common outlet or an identifiable
water body such as a river, stream, lake or wetland. The six major watersheds in King County
are Cedar River, Green River, Skykomish River, Snoqualmie River and White River and the
Puget Sound. These watersheds contain a total of 72 individual drainage basins. (See Chapter
Four, Environment)
Well Head Protection
Well head protection is another way that King County can protect its groundwater resource. This
program directs purveyors to identify 1, 5, and 10-year time of travel to their well(s) to identify
contamination sources, and to propose methods to reduce or eliminate contamination sources.
Wetland
The term wetland means those areas that are inundated or saturated by surface or ground water
at a frequency and duration sufficient to support, and that under normal circumstances do
support, a prevalence of vegetation typically adapted for life in saturated soil conditions.
Wetlands generally include swamps, marshes, bogs and similar areas. Wetlands do not include
those artificial wetlands intentionally created from nonwetland sites, including, but not limited to,
irrigation and drainage ditches, grass-lined swales, canals, detention facilities, wastewater
treatment facilities, farm ponds, landscape amenities, or those wetlands created after July 1,
1990 that were unintentionally created as a result of the construction of a road, street or highway.
Wetlands shall include those artificial wetlands intentionally created from nonwetland areas to
mitigate conversion of wetlands.
Wetland Banking
Wetland banking is a process that allows certain wetlands to be developed if the development is
accompanied by the restoration or creation of wetlands in other areas. (See Chapter Four,
Environment)
Wetland Functions
Functions refer to the ecological (physical, chemical and biological) workings or attributes of a
wetland regardless of their importance to society. Food chain support or the transport and
transformation of chemicals in ecosystems are examples of wetland functions. Water quality
maintenance, flood storage, and wildlife habitat are examples of ecological functions to which
society attributes a value. (See Chapter Four, Environment)
Wetland Values
Values are estimates, usually subjective, of the worth, merit, quality, or importance of wetland
attributes that are valuable and beneficial to society. Values vary by watershed or human
community. Education, research, aesthetics, and recreation are examples of other wetland
attributes that may be considered values in that they are beneficial to society.
Will
See definition for "shall".
September 2004 G-16
Frequently Used Acronyms
APO
BMP
CIP
CPP
ESA
FCC
FPO
GMA
GMPC
HOT
HOV
ITS
KCCP
LOS
LSRA
MPS
PAA
PBRS
PSRC
RSRA
RWSP
SEPA
sov
TAM
TDC
TOM
TNR
TOD
UGA
UPD
UTRC
Agricultural Production District
Best Management Practices
Capital Improvement Program
Countywide Planning Policy
Endangered Species Act
Fully Contained Community
Forest Production District
Growth Management Act
Growth Management Planning Council
High Occupancy Toll lane
High Occupancy Vehicle
Intelligent Transportation Systems
King County Comprehensive Plan
Level of Service
Locally Significant Resource Area
Mitigation Payment System
Potential Annexation Area
Public Benefit Rating System
Puget Sound Regional Council
Regionally Significant Resource Area
Regional Wastewater Services Plan
State Environmental Policy Act
Single Occupancy Vehicle
Transportation Adequacy Measure
Transfer of Development Credits
Transportation Demand Management
Transportation Needs Report
Transit Oriented Development
Urban Growth Area
Urban Planned Development
Utilities Technical Review Committee
G-17 September 2004
I
2
3
4
5
6
7
8
9
10
11
Proposed l\'o. 2004-0114.3
KING COUNTY
Signature Report
October 6, 2004
Ordinance 15028
1200 King County Courthouse
516 Third A venue
S~attk, \VA 981 04
Sponsors Constantine, Edmonds and Phillips
AN ORDINANCE relating to comprehensive planning and
zoning; adopting the King County Comprehensive Plan
2004 amendments to the Comprehensive Plan 2000 and
area zoning, in accordance with the Washington State
Growth Management Act; and amending Ordinance 263,
Article 2, Section 1, as amended, and K.C.C. 21.12.0 I 0,
Ordinance 12824, Section 3, as amended, and K.C.C.
20.12.050 and Ordinance 10511, Section 7, as amended,
and K.C.C. 20.36.100.
12 BE IT ORDAINED BY THE COUNCIL OF KING COUNTY:
13 SECTION 1. Findings. For the purposes of effective land use planning and
14 regulation, the King County council makes the following legislative findings:
15 A. King County has adopted the 2000 King County Comprehensive Plan to meet
16 the requirements of the Washington State Growth Management Act ("GMA");
0-1
Ordinance 15028
17 B. The King County Code authorizes a review of the Comprehensive Plan and
18 allows substantive amendments to the Comprehensive Plan once every four years and the
19 King County Comprehensive Plan 2004 amendments represent the second major review
20 of the Comprehensive Plan since 1994;
21 C. The GMA requires that the Comprehensive Plan and development regulations
22 be subject to continuing review and evaluation by the county;
23 D. The GMA requires each county that designates urban growth areas to review
24 the urban growth area at least every ten years and the GMA requires that King County
25 complete the review and evaluation of its urban growth area on or before December I,
26 2004;
27 E. The GMA requires that King County adopt development regulations to be
28 consistent with and implement the Comprehensive Plan; and
29 F. The changes to zoning contained in this ordinance are needed to maintain
30 conformity with the King County Comprehensive Plan, as required by the GMA. As
31 such, they bear a substantial relationship to, and are necessary for, the public health,
32 safety and general welfare of King County and its residents.
33 SECTION 2. Ordinance 263, Article 2, Section I, as amended, and K.C.C.
34 20.12.10 are each hereby amended to read as follows:
35 Comprehensive Plan adopted.
36 A. Under the King County Charter, the state Constitution and the Washington State
3 7 Growth Management Act, chapter 36. 70A RCW, the 1994 King County Comprehensive
3 8 Plan is adopted and declared to be the Comprehensive Plan for King County until
39 amended, repealed or superseded. King County ((f!a5)) performed its first comprehensive
0-2
Ordinance 15028
40 four-cycle review of the Comprehensive Plan. As a result of the review, King County
41 amended the 1994 Comprehensive Plan through passage of the King County
42 Comprehensive Plan 2000. King Countv performed its second comprehensive four-cycle
43 review of the Comprehensive Plan in 2004. As a result of the review, King County
44 amended the 2000 Comprehensive Plan through passage of the King County
45 Comprehensive Plan 2004. The Comprehensive Plan shall be the principal planning
46 document for the orderly physical development of the county and shall be used to guide
4 7 subarea plans, functional plans, provision of public facilities and services, review of
48 proposed incorporations and annexations, development regulations and land development
49 decisions.
50 B. The amendments to the 1994 King County Comprehensive Plan contained in
51 Appendix A to Ordinance 12061 (King County Comprehensive Plan 1995 amendments)
5 2 are hereby adopted.
53 C. The amendments to the 1994 King County Comprehensive Plan contained in
54 Attachment A to Ordinance 12170 are hereby adopted to comply with the Central Puget
55 Sound Growth Management Hearings Board Decision and Order in Vashon-Maury Island,
56 et. al. v. King County, Case No. 95-3-0008.
57 D. The Vashon Town Plan contained in Attachment I to Ordinance 12395 is
58 adopted as a subarea plan of the King County Comprehensive Plan and, as such, constitutes
59 official county policy for the geographic area of unincorporated King County defined in the
60 plan and amends the 1994 King County Comprehensive Plan Land Use Map.
61 E. The amendments to the 1994 King County Comprehensive Plan contained in
62 Appendix A to Ordinance 1250 I are hereby adopted to comply with the Order of the
0-3
Ordinance 15028
63 Central Puget Sound Growth Management Hearings Board in Capac-Preston Mill, Inc., et
64 al, v. King County, Case No. 96-3-0013 as amendments to the King County
65 Comprehensive Plan.
66 F. The amendments to the 1994 King County Comprehensive Plan contained in
67 Appendix A to Ordinance 12531 (King County Comprehensive Plan 1996 amendments)
68 are hereby adopted as amendments to the King County Comprehensive Plan.
69 G. The Black Diamond Urban Growth Area contained in Appendix A to Ordinance
70 12533 is hereby adopted as an amendment to the King County Comprehensive Plan.
71 H. The 1994 King County Comprehensive Plan and Comprehensive Plan Land
72 Use Map are amended to include the area shown in Appendix A of Ordinance 12535 as
73 Rural City Urban Growth Area. The language from Section ID of Ordinance 12535 shall
74 be placed on Comprehensive Plan Land Use Map page #32 with a reference marker on the
75 area affected by Ordinance 12535.
76 I. The amendments to the 1994 King County Comprehensive Plan contained in
77 Appendix A to Ordinance 12536 (1997 Transportation Need Report) are hereby adopted as
78 amendments to the King County Comprehensive Plan.
79 J. The amendments to the 1994 King County Comprehensive Plan contained in
80 Appendix A to Ordinance 12927 (King County Comprehensive Plan 1997 amendments)
81 are hereby adopted as amendments to the King County Comprehensive Plan.
82 K. The amendments to the 1994 King County Comprehensive Plan contained in
83 the 1998 Transportation Needs Report, contained in Appendices A and B to Ordinance
84 12931 and in the supporting text, are hereby adopted as amendments to the King County
85 Comprehensive Plan.
0-4
Ordinance 15028
86 L. The amendments to the 1994 King County Comprehensive Plan contained in
87 Appendix A to Ordinance 13273 (King County Comprehensive Plan 1998 amendments)
88 are hereby adopted as amendments to the King County Comprehensive Plan.
89 M. The 1999 Transportation Needs Report contained in Attachment A to
90 Ordinance 13339 is hereby adopted as an amendment to the 1994 King County
91 Comprehensive Plan, Technical Appendix C, and the amendments to the 1994 King
92 County Comprehensive Plan contained in Attachment B to Ordinance 13339 are hereby
93 adopted as amendments to the King County Comprehensive Plan.
94 N. The amendments to the 1994 King County Comprehensive Plan contained in
95 Attachment A to Ordinance 13672 (King County Comprehensive Plan 1999 amendments)
96 are hereby adopted as amendments to the King County Comprehensive Plan.
97 0. The 2000 Transportation Needs Report contained in Attachment A to this
98 Ordinance 13674 is hereby adopted as an amendment to the 1994 King County
99 Comprehensive Plan, Technical Appendix C.
00 P. The Fall City Subarea Plan contained in Attachment A to Ordinance 13875 is
· 01 adopted as a subarca plan of the King County Comprehensive Plan and, as such, constitutes
02 official county policy for the geographic area of unincorporated King County defined in the
· 03 plan. The Fall City Subarea Plan amends the 1994 King County Comprehensive Plan land
.04 use map by revising the Rural Town boundaries of Fall City.
05 Q. The amendments to the King County Comprehensive Plan contained in
106 Attachment A to Ordinance 13875 are hereby adopted as amendments to the King County
07 C omprehcnsive Plan.
0-5
Ordinance 15028
108 R. The Fall City area zoning amendments contained in Attachment A to Ordinance
I 09 13875 are adopted as the zoning control for those portions of unincorporated King County
110 defined in the attachment. Existing property-specific development standards (p-suffix
111 conditions) on parcels affected by Attachment A to Ordinance 13875 do not change except
112 as specifically provided in Attachment A to Ordinance 13875.
113 S. The amendments to the 1994 King County Comprehensive Plan Land Use Map
114 contained in Attachment A to Ordinance 13987 are hereby adopted to comply with the
115 Central Puget Sound Growth Management Hearings Board Decision and Order on
116 Supreme Court Remand in Vashon-Maury Island, et. al. v. King County, Case No. 95-3-
117 0008 (Bear Creek Portion).
118 T. The 200 I transportation needs report contained in Attachment A to Ordinance
119 14010 is hereby adopted as an amendment to the 1994 King County Comprehensive Plan,
120 technical appendix C.
121 U. The amendments to the 1994 King County Comprehensive Plan contained in
122 Attachments A, B and C to Ordinance 14044 (King County Comprehensive Plan 2000) are
123 hereby adopted as amendments to the King County Comprehensive Plan. Attachment A
124 amends the policies, text and maps of the Comprehensive Plan. Amendments to the
125 policies are shown with deleted language struck out and new language underlined. The text
126 and maps in Attachment A replace the previous text and maps in the Comprehensive Plan.
127 Attachment B to Ordinance 14044 contains technical appendix A (capital facilities), which
128 replaces technical appendix A to the King County Comprehensive Plan, technical appendix
129 C (transportation), which replaces technical appendix C to the King County
130 Comprehensive Plan, and technical appendix M (public participation), which is a new
0-6
Ordinance 15028
131 technical appendix that describes the public participation process for the King County
132 Comprehensive Plan 2000. Attachment C includes amendments to the King County
133 Comprehensive Plan Land Use Map. The land use amendments contained in Attachment C
134 are adopted as the official land use designations for those portions of unincorporated King
135 County defined in Attachment C to Ordinance 14044.
136 V. The Snoqualmie Urban Growth Area Subarea Plan contained in Attachment A
137 to Ordinance 14117 is adopted as a subarea plan of the King County Comprehensive Plan
138 and, as such, constitutes official county policy for the geographic area of unincorporated
139 King County defined in the plan. Attachment B to Ordinance 14117 amends the King
140 County Comprehensive Plan 2000 land use map by revising the Urban Growth Area for the
141 City of Snoqualmie. Attachment C to Ordinance 14117 amends the policies of the
142 Comprehensive Plan.
43 W. The Snoqualmie Urban Growth Area Subarea Plan area zoning amendments in
144 Attachment D to Ordinance 14117 are adopted as the zoning control for those portions of
45 unincorporated King County defined in the attachment. Existing property-specific
'.46 development standards (p-suffix conditions) on parcels affected by Attachment D to
4 7 Ordinance 1411 7 do not change
· 48 X. The amendments to the King County Comprehensive Plan 2000 contained in
A9 Attachment B to Ordinance 14156 are hereby adopted as amendments to the King County
50 Comprehensive Plan.
, 51 Y. The amendments to the King County Comprehensive Plan 2000 contained in
52 Attachment A to Ordinance 14185 are hereby adopted as amendments to the King County
· 53 Comprehensive Plan in order to comply with the order of the Central Puget Sound Gro'wth
0-7
Ordinance 15028
154 Management Hearings Board in Green Valley et al, v. King County, CPSGMHB Case No.
155 98-3-0008c, Final Decision and Order (1998) and the order of the Washington Supreme
156 Court in King County v. Central Puget Sound Growth Management Hearings Board, 142
157 Wn.2d 543, 14 P.3d 133 (2000).
158 Z. The amendments to the King County Comprehensive Plan 2000 contained in
159 Attachment A to Ordinance 14241 (King County Comprehensive Plan 2001 Amendments)
160 are hereby adopted as amendments to the King County Comprehensive Plan.
161 AA. The amendment to the King County Comprehensive Plan 2000 contained in
162 Attachment A to Ordinance 14286 is hereby adopted as an amendment to the King County
163 Comprehensive Plan in order to comply with the Central Puget Sound Growth
164 Management Hearings Board's Final Decision and Order in Forster Woods Homeowners'
165 Association and Friends and Neighbors of Forster Woods, et al. v. King County, Case No.
166 01-3-0008c (Forster Woods), dated November 6, 2001.
167 BB. The amendments to the King County Comprehensive Plan 2000 contained in
168 Attachment A to Ordinance 14448 (King County Comprehensive Plan 2002 Amendments)
169 are hereby adopted as amendments to the King County Comprehensive Plan.
170 CC. The amendments to the King County Comprehensive Plan 2000 contained in
171 Attachment A to Ordinance 14775 (King County Comprehensive Plan 2003 Amendments)
172 are hereby adopted as amendments to the King County Comprehensive Plan.
173 DD. The amendments to the King County Comprehensive Plan 2000 contained in
174 Attachments A. B, C. D and E to this ordinance (King County Comprehensive Plan 2004)
175 are hereby adopted as amendments to the King County Comprehensive Plan. Attachment
176 A. Part I, to this ordinance amends the policies, text and maps of the Comprehensive Plan.
0-8
Ordinance 15028
1 77 Attachment A, Part II, to this ordinance includes amendments to the King County
178 Comprehensive Plan Land Use Map. The land use amendments contained in Attachment
179 A. Part II, to this ordinance are adopted as the official land use designations for those
180 portions of unincorporated King County defined in Attachment A, Part II, to this
181 ordinance. Attachment B to this ordinance contains Technical Appendix A (Capital
182 Facilities). which replaces technical appendix A to the King County Comprehensive Plan.
183 Attachment C to this ordinance contains Technical Appendix B (Housing), which replaces
-184 Technical Appendix B to the King Countv Comprehensive Plan. Attachment D to this
185 ordinance contains Technical Appendix C (Transportation). which replaces Technical
: 86 Appendix C to the King County Comprehensive Plan 2000. Attachment E to this
187 ordinance contains Technical Appendix D (Growth Targets and the Urban Growth Area
, 88 2004).
89 SECTION 3. The Comprehensive Plan 2004 zoning amendments contained in
190 Attachment A, Part II, to this ordinance are adopted as the official zoning control for
91 those portions of unincorporated King County defined in Attachment A, Part II, to this
'92 ordinance in accordance with K.C.C. 20.12.050. Existing property-specific development
93 conditions (p-suffix conditions) and special district overlays on parcels affected by the
· 94 Comprehensive Plan 2004 area zoning amendments, whether adopted through
95 reclassifications or area zoning, are retained by this ordinance except as specifically
'96 amended by this ordinance. Property-specific development standards adopted, repealed
, 97 or amended by this ordinance shall amend Appendix A of Ordinance 12824 in
98 accordance with K.C.C. 20.12.050. Special district overlays adopted, repealed or
· 99 amended by this ordinance shall amend Appendix B of Ordinance 12824 in accordance
0-9
Ordinance 15028
200 with K.C.C. 20.12.050.
201 SECTION 4. Ordinance 12824, Section 3, as amended, and K.C.C. 20.12.050 are
202 each hereby amended to read as follows:
203 Zoning, potential zoning, property-specific development standards, special
204 district overlays, regional use designations and interim zoning. Zoning adopted
205 pursuant to this section shall constitute official zoning for all of unincorporated King
206 County.
207 A. Official zoning, including but not limited top-suffix, so-suffix and potential
208 zoning, is contained in the SITUS file and is depicted on the official zoning maps, as
209 maintained by the department of development and environmental services.
210 B. Appendix A of Ordinance 12824, as amended by this ordinance, is hereby
21 l adopted to constitute and contain all property-specific development standards (p-suffix
212 conditions) applicable in unincorporated King County. The property specific development
213 standards (p-suffix conditions) in effect or hereinafter amended shall be maintained by the
214 department of development and environmental services in the Property Specific
215 Development Conditions notebook. Any adoption, amendment or repeal of property-
216 specific development standards shall amend, pursuant to this section, Appendix A of
217 Ordinance 12824 as currently in effect or hereafter amended.
218 C. Appendix B of Ordinance 12824, as amended by this ordinance, is hereby
219 adopted to constitute and contain special district overlays applied through Ordinance
220 12824. The special district overlays in effect or hereinafter amended shall be maintained
221 by the department of development and environmental services in the Special District
222 Overlay Application Maps notebook. Any adoption, amendment or repeal of special
0-10
Ordinance 15028
223 district overlays shall amend, pursuant to this section, Appendix B of Ordinance 12824 as
224 currently in effect or hereafter amended.
225 SECTION 5. Ordinance 10511, Section 7, as amended, and K.C.C. 20.36.100 are
226 each hereby amended to read as follows:
227 Criteria for approval -public benefit rating system for open space land -
228 rating system -bonus system -super bonus system.
229 A. To be eligible for open space classification under the public benefit rating
230 system, property must contain one or more priority open space resources. These
231 resources are ranked as high priority, medium priority and low priority resources and are
232 based on the adopted King County Open Space Plan referenced in K.C.C. 20.12.380.
233 High priority resources receive five points each, medium priority resources receive three
234 points each and low priority resources receive one point each. Property can receive a
235 maximum of thirty points from no more than six open space priority resources. In
236 addition, bonus points and super bonus points may be awarded pursuant to K.C.C.
!37 20.36.1008 and C and a property can achieve a maximum of fifty-two points through the
~38 rating system and the bonus system. Portions of property may also qualify for open space
239 designation. Complete definitions of each resource, sources and eligibility standards are
~40 fully described in the summary report adopted by reference by K.C.C. 20.36.150. The
.:41 department of natural resources and parks shall have administrative authority to interpret
142 issues relating to the priority resource definitions and eligibility standards outlined in the
L43 summary report.
'44 1. High priority resources -five points each .
. AS a. Active or passive recreation area.
0-11
Ordinance 15028
246 b. Property under option for purchase as park, recreation, open space land or
24 7 CIP mitigation site.
248 c. Aquifer protection area.
249 d. Shoreline: "Conservancy" environment.
250 e. Scenic resource, viewpoint or view corridor.
251 f. Surface water quality buffer area.
252 g. Open space close to urban or growth area.
253 h. Significant plant, wildlife or salmonid habitat area.
254 1. Significant aquatic ecosystem.
255 J. Historic landmark/archaeological site: designated site.
256 k. Trail linkage.
257 I. Urban or growth area open space.
258 m. Farm and agricultural conservation land.
259 n. Forest stewardship land.
260 o. Equestrian-pedestrian trail linkage.
261 p. Rural stewardship land.
262 q. Watershed protection.
263 2. Medium priority resources -three points each.
264 a. Public land or right-of-way buffer.
265 b. Special native plant site.
266 c. Natural shoreline environment.
267 d. Geological feature.
268 e. Eligible historic landmark or archaeological site.
0-12
Ordinance 15028
269 f. Buffer to designated historic landmark/archaeological site.
270 g. Special animal site.
271 3. Low priority resource -one point.
272 a. Buffer to eligible historic/archaeological site.
273 B. Property qualifying in the specific high, medium or low priority categories
274 may receive up to twenty-two bonus points if the following additional qualifications are
?.75 met:
276 1. Resource restoration -five points.
2 77 2. Bonus surface water quality buffer -three or five points.
278 3. Contiguous parcels under separate ownership -two points.
'179 4. Conservation or Historic Preservation Easement in perpetuity -five points.
280 5. Bonus public access points.
!81 a. Unlimited public access -five points.
282 b. Limited public access -sensitive area -five points.
183 c. Limited public access -three points.
rn4 C. Property with at least one high priority resource and which allows unlimited
:85 public access, or limited public access if due to resource sensitivity, and which conveys a
~86 conservation, historic preservation, or trail easement in perpetuity, in a fom1 approved by
c.87 the county, shall be automatically eligible for current use value at ten percent of market
-88 value.
_g9 SECTION 6. Work program. The council hereby adopts the following work
90 program items as part of the King County Comprehensive Plan 2004:
0-13
Ordinance 15028
291 A. The executive shall transmit to the council by December 31, 2004, stand-alone
292 legislation concerning the Green Building Initiative, including the Leadership in Energy
293 and Environmental Design (LEEDs(TM)) certification program. The legislation must be
294 filed in the form of fifteen copies with the clerk of the council, who shall retain the
295 original and shall forward copies to each councilmember and to the lead staff for the
296 budget and fiscal management committee or its successor. The transmittal package shall
297 include a fiscal note to enable the council to conduct an analysis of the financial impacts
298 of the proposal; and
299 B. The executive shall complete the studies required by policies R-106 and R-
300 107, and shall transmit them to the council by December 31, 2005. The studies must be
301 filed in the form of fifteen copies with the clerk of the council, who shall retain the
302 original and shall forward copies to each councilmember and to the lead staff for the
303 growth management and unincorporated areas committee or its successor; and
304 C. By December 31, 2005, the executive shall develop through an administrative
305 rule making process a set of criteria for making decisions on a case-by-case basis as to
306 whether existing water systems can meet their duty to supply water throughout their
307 assigned water service areas in a timely and reasonable manner, and whether those
308 systems can otherwise serve water to proposed new development with reasonable
309 economy and efficiency;
310 D. By December 31, 2005, the executive shall transmit to the council a work plan
311 for gathering data concerning the existing and potential impact of exempt wells on
312 groundwater levels, stream flows and the general health of the aquifer in areas where
313 exempt wells are used for water supply, and developing strategies to address the
0-14
314
315
316
317
318
319
320
321
322
323
324
325
l26
/ p27
l28
329
J30
'131
i32
133
J34
' 35
336
Ordinance 15028
identified impacts. The work plan shall include the participation ofrelevant state
agencies, and shall reflect ongoing work related to groundwater management areas and
plans and salmon recovery plans. The work plan must be filed in the form of fifteen
copies with the clerk of the council, who shall retain the original and shall forward copies
to each councilmember and to the lead staff for the natural resources and utilities
committee or its successor;
E. The executive shall complete a subarea planning process to study rural-zoned
properties in the Sammamish valley agricultural production district, and shall transmit
any required Comprehensive Plan amendments to the council as part of a future
amendment to the Comprehensive Plan. The subarea plan must be filed in the form of
fifteen copies with the clerk of the council, who shall retain the original and shall forward
copies to each councilmember and to the lead staff for the growth management and
unincorporated areas committee or its successor;
F. The executive shall complete a study of existing property-specific (p-suffix)
development conditions for properties on Vashon and Maury Islands for the purpose of
determining whether any p-suffix conditions are no longer applicable and should be
removed from the zoning of individual parcels. The executive shall transmit any required
legislation to the council by March 1, 2005. The legislation must be filed in the form of
fifteen copies with the clerk of the council, who shall retain the original and shall forward
copies to each councilmember and to the lead staff for the growth management and
unincorporated areas committee or its successor;
G. The executive shall, contingent upon council appropriation of funds through
the 2005 budget, complete a subarea planning process to study non-conforming industrial
0-15
Ordinance 15028
337 uses along the Maple Valley highway for properties adjacent to and near the old King
338 County shop site for possible redesignation to a commercial center, and shall transmit any
339 required Comprehensive Plan amendments to the council as part of the 2005 amendment
340 to the Comprehensive Plan. The subarea plan must be filed in the form of fifteen copies
341 with the clerk of the council, who shall retain the original and shall forward copies to
342 each councilmember and to the lead staff for the growth management and unincorporated
343 areas committee or its successor;
344 H. The executive shall, contingent upon council appropriation of funds through
345 the 2005 budget, complete a subarea planning process to study expansion of the east
346 Redmond rural neighborhood, and shall transmit any required Comprehensive Plan
34 7 amendments to the council as part of the 2005 amendment to the Comprehensive Plan.
348 The subarea plan must be filed in the form of fifteen copies with the clerk of the council,
349
350
who shall retain the original and shall forward copies to each councilmember and to the
lead staff for the growth management and unincorporated areas committee or its
351 successor;
352 I. The executive shall complete a study of the county's development regulations
353 governing accessory dwelling units in the urban and rural areas for the purpose of
354 determining if such regulations provide adequate flexibility and fairness while meeting
355 the goals of the Growth Management Act. As part of the study, the executive shall
356 examine development regulations governing accessory dwelling units in other
357 jurisdictions in King County, and in surrounding counties. The executive shall transmit
358 any required legislation to the council by December 31, 2005. The legislation must be
359 filed in the form of fifteen copies with the clerk of the council, who shall retain the
0-16
',
•
Ordinance 15028
360 original and shall forward copies to each councilmember and to the lead staff for the
361 growth management and unincorporated areas committee or its successor; and
I
362 J. The executive shall complete a study of cottage housing models in the Puget
363 Sound region and, upon completion of the study, shall propose amendments to the
· 364 county's policies and development regulations if warranted. The executive shall transmit
365 any required legislation to the council by December 31, 2005. The legislation must be
366 filed in the form of fifteen copies with the clerk of the council, who shall retain the
367 original and shall forward copies to each councilmember and to the lead staff for the
368 growth management and unincorporated areas committee or its successor.
369 SECTION 7. Severability. If any provision of this ordinance or its application to
0-17
Ordinance 15028
370 any person or circumstance is held invalid, the remainder of the ordinance or the
3 71 application of the provision to other persons or circumstances is not affected.
372
Ordinance 15028 was introduced on 3/8/2004 and passed as amended by the
Metropolitan King County Council on 9/27/2004, by the following vote:
ATTEST:
Yes: 7 -Mr. Phillips, Ms. Edmonds, Mr. Pelz, Mr. Ferguson, Mr. Gossett, Ms.
Patterson and Mr. Constantine
No: 4 -Ms. Lambert, Mr. McKenna, Mr. Hammond and Mr. Irons
Excused: 2 -Mr. von Reichbauer and Ms. Hague
KING COUNTY COUNCIL
KING COUNTY, WASHINGTON
APPROVED this 29th day of September, 2004.
Attachments A. 2004 King County Comprehensive Plan, Metropolitan King Cmmty Council,
Adopted September 27, 2004, B. King County Comprehensive Pian 2004, Technical
Appendix A Capital Facilities, Adopted September 27, 2004, C. King County
Comprehensive Plan, Technical Appendix B Housing, Adopted September 27, 2004,
D. King County Comprehensive Plan 2004 Technical Appendix C Transportation,
Adopted September 27, 2004, E. King County Comprehensive Pian 2004, Technical
Appendix D Growth Targets and the Urban Growth Area, Adopted September 27,
2004, F. Map Amendments, Adopted September 27, 2004
0-18
SE 144TH STREET
LEVEL 3 DOWNSTREAM DRAINAGE
ANALYSIS
Prepared for:
Mr. Dave Petrie
8 I t S( . 2 /31, l r:t .
Des 1v101,1es. WA 98 198
KBS Development
l)J?ONE:.8tl1St1f,etSuitt· 100
Be l lr>\·ll,' VV/\ '::18()05
Eagle Creek l a nd & Development, L LC
13/(ll Sf:-lr;·~,cl St
f,<,,_..riJ Vi/\ 98(14?
tJw
09
Preparecf bv:
Ed McCartl1y P.E., P.S
qqr) l 1 t I · i\\.e1111t: SE
Pu di ·11. W.1\ ~J80:)9
l, I I l ) ) 1 2 i' J ~.l / Jtl
~c1, 1 ·l >1.)1 > i I 3,IJ2
ltHlP 15. 2007
SE 144TH STREET
LEVEL 3 DOWNSTREAM DRAINAGE ANALYSIS
SE 144TH STREET
LEVEL 3 DOWNSTREAM DRAINAGE ANALYSIS
SE 144TH STREET
LEVEL 3 DOWNSTREAM DRAINAGE ANALYSIS
SE 144TH STREET
LEVEL 3 DOWNSTREAM DRAINAGE ANALYSIS
SE 144TH STREET
LEVEL 3 DOWNSTREAM DRAINAGE ANALYSIS
SE 144TH STREET
LEVEL. 3 DOWNSTREAM DRAINAGE ANALYSIS
SE 144TH STREET
LEVEL. 3 DOWNSTREAM DRAINAGE ANALYSIS
Acknowledgements
SE 1441h Street
LEVEL 3 DOWNSTREAM DRAINAGE ANALYSIS
Prepared by:
Ed McCarthy, P.E., P.S.
9957 171" Avenue SE
Renton, WA 98059
Tel. (425) 271-5734
Fax (425) 271-3432
Prepared for:
Mr. Dave Petrie
811 So. 273rd Ct
Des Moines, WA 98198
KBS Development
12320 NE 8th Street Suite 100
Bellevue WA 98005
Eagle Creek Land & Development, LLC
13701 SE 253rd St
Kent, WA 98042
June 16, 2007
TABLE OF CONTENTS
1. Background Information ............................................................................................. 1-1
2. Hydrologic and Hydraulic Analysis of SE 144th Street.. ............................................ 2-1
3. Drainage Mitigation Options ...................................................................................... 3-1
4. Key Results and Recommendations ............................................................................ 4-1
5. References ................................................................................................................... 5-1
LIST OF TABLES
Table 1. Contributing Basins .......................................................................................... 2-4
Table 2. Peak Flow Rates at Key Locations ................................................................... 2-8
LIST OF FIGURES
Figure I. Vicinity Map .................................................................................................... 1-2
Figure 2. Study Area ....................................................................................................... 2-2
Figure 3. Soils Map ......................................................................................................... 2-3
Figure 4. Basin Map ........................................................................................................ 2-6
Figure 5. SE 144th Street Conveyance System ............................................................... 2-9
Figure 6. Offsite Mitigation Options .............................................................................. 3-2
APPENDICES
Appendix A. Photographs of the Downstream System
Appendix B. KCRTS Documentation for Contributing Basins
Appendix B. l KCRTS Time Series Calculations
Appendix B.2 KCRTS Pond Designs
Appendix B.3 KCRTS Peak Flow Rates
Appendix C. XP-SWMM Model Results
Appendix D. HEC-RAS Analysis of Roadway Conveyance
ii
1. BACKGROUND INFORMATION
This report provides an assessment of the conveyance system along SE 144th Street in the Renton
Highlands area of King County, Washington (Figure I). The study area is located within a
catchment of Orting Hill subbasin (Tributary 0307) of the Cedar River watershed (King County
Department of Natural Resources, 1993 and 1997). The conveyance system has a contributing
drainage area of 253 acres. The conveyance route is downstream from three proposed single-
family residential developments that are currently under drainage review at King County DOES.
These developments include Threadgill Plat, Liberty Gardens, and Cavella.
This Level 3 Downstream Drainage Analysis has been prepared at the request of DOES.
Flooding currently occurs at locations along the SE 144th Street conveyance system. Flooding
has been observed at the intersection of the 162nd Avenue right-of-way and SE 144th Street
(Photo No. 1 in Appendix A). In addition, King County Roads Division has recently constructed
conveyance improvements at the intersection of l 60'h Avenue SE and SE 144th Street,
presumably to collect overflow from surrounding catch basins. While the conveyance system is
apparently undersized for its contributing basin, there is a surprisingly little documentation in
King County's records that flooding exists or has occurred in the past along SE 144th Street.
Neither the long-time owner of Alpine Nursery nor an original resident at Carol wood, that I
interviewed, had observed road flooding along SE l 44'h Street over the past several years.
The evaluations presented in this report are intended accomplish the following:
• Delineate the conveyance network's contributing basins and quantify the flow rates
draining to the conveyance network.
• Estimate the conveyance capacity of the system, including the 18-inch diameter pipe,
northerly roadside ditch, and roadway.
• Identify areas of flooding.
• Develop conceptual drainage solutions to mitigate impacts from the proposed and
future development projects.
1-1
SE J 4,(h Street-June 2007
\
\
\
\
D
\
\
\,__)
§
'l:,
0
0
Vicinity Map
SE 144th Street Drainage Analysis
King County, Washington
w
(/)
Q)
> <{
SE 144th St
/
\
a
C)
/~
0
0
2,000
.__ ___ ____. Feet
0
~
\
\
\
0
'
\J
\~
\ \
Ed McCarthy, PE, PS
9957 171st Averue SE
Renton, Washington 98059
Phone: (425) 271-5734
Fax (425) 27 1-3432
~
\
r:
J
a
G OD
l'roj No
"'" 6/15/07
Figure 1
2. HYDROLOGIC AND HYDRAULIC ANALYSIS OF SE 144TH STREET
2.1 Contributing Basins
In effort to develop a hydro logic model of the basins contributing to the conveyance system
along SE 144th Street, basin boundaries were delineated using the following resources:
• City of Renton aerial topography (I-meter contours)
• Level I Downstream Drainage Analysis for lbreadgill Plat (Baima & Holmberg, Inc.
and Ed McCarthy, PE, PS. November 18, 2005)
• Level 1 Downstream Drainage Analysis for Evendell Plat (Haozous Engineering,
June 15, 2001)
• Technical Information Report for Hamilton Place (Barghausen Consulting Engineers,
June 2003)
• Technical Information Report for Evendell Plat (Haozous Engineering, June 15,
2001)
• Technical Information Report for Nichol's Plat (Haozous Engineering, May 2003)
• Technical Information Report for Liberty Grove (Daley-Morrow-Poblete, Inc.,
February 2003)
• Record drawings for stormwater design for Carolwood (May 1977)
• Record drawings for stormwater design for Liberty Lane (Doneshvar and Associates,
PS, June 13, 1979)
• Record drawings for SE 144th Street (King County Department of Public Works,
January 18, 1984)
• Record drawings for l 54'h Place SE Slope Stabilization Project (King County
Department of Public Works, June 23, 1997)
• Field verification of key locations in the watershed
The study area under consideration is shown in Figure 2. Cover types within the study area
include those associated with relatively dense single-family residences, forest, and pasture. Soils
in the watershed are mostly of the Alderwood series (Figure 3). However, a band of outwash
soils (Everett series) exists along SE 144 1h Street, at the southern boundary of the study basin and
extends to the south.
In total, an area of 253 acres was calculated to drain to the conveyance system (Table I). Based
on cover type estimates, about 25 percent of the contributing area is effective impervious
surfaces. The size and boundaries of the delineated subbasins draining to the conveyance system
2-1
SE l4¢hStreet-June2007
Study Area
SE 144th Street Drainage Analysis () 400
.__ ____ _. Feet
King County, Washington
Ed McCarthy, PE, PS
9957 171st Avenue SE
Re nton, Wash ington 98059
Ph one: (425) 271-5734
Fax : (425) 271-3432
Date : 6 /15/07
Figure 2
Table 1. Contributing Basins
Basin Till Till Till Outwash Outwash Outwash
ID Forest Pasture Grass Forest Pasture Grass Impervious Total
AC AC AC AC AC AC AC AC
JO -0.16 0.29 0.08 0.53
20 -0.30 1.05 0.51 1.86
30 -0.31 0.91 0.41 1.62
40 0.26 0.30 0.56
42 -0.03 0.96 0.67 1.66
44 0.99 0.99
50 0.51 0.51
52 -0.01 0.80 -0.01 0.80 1.15 2.77
54 0.03 0.03 0.83 0.04 0.04 1.24 1.44 3.64
60 0.52 0.52
70 -0.51 1.70 -0.34 1.13 1.34 5.04
80 5.28 0.12 4.35 0.59 0.01 0.48 3.40 14.23
90 0.40 0.40
JOO 0.45 0.33 0.61 0.17 1.56
106 2.50 0.12 3.34 0.12 3.34 4.64 14.05
110 6.43 12.24 12.33 7.10 38.10
120 0.58 1.00 1.58
130 2.49 7.12 5.80 1.58 16.99
200 4.45 0.14 1.79 1.18 7.56
210 3.31 1.70 4.60 2.93 12.55
220 1.56 1.90 3.46
230 3.95 5.71 9.66
232 1.38 ---1.38
240 3.65 4.48 8. 13
241 0.23 2.99 3.68 6.90
244 0.71 1 I .46 10.75 4.68 27.60
250 -0.17 4.66 3.23 8.06
260 2.33 1.74 4.07
270 --2.22 1.60 3.82
300 9.47 1.73 4.13 1.56 16.89
304 2.12 1.36 5.73 3.74 12.95
306 1.25 0.15 0.28 0.08 1.75
310 9.32 ---9.32
320 8.92 0.18 0.33 0.09 9.52
330 1.37 0.34 0.62 0.17 2.50
59.71 42.22 75.40 0.63 1.32 10.47 62.98 252.73
Effective Impervious = 25%
2-4
SE 14.fn Street-June 2007
were driven by the locations of catch points and the watershed's topography. A total of35
subbasins were delineated (Figure 4).
Recent higher density single-family developments contributing to the conveyance system include
Hamilton Place (Catchment C-260), Evendell Plat (Catchment C-230), Nichols Place
(Catchment C-220), and Liberty Grove (Catchments C-240 and 241 ). The attenuation provided
by the stormwater ponds for these developments was included in the hydrologic model of the
basin. In addition, the stormwater pond for Carolwood (Catchment C-106) infiltrates runoff for
at least up to the 100-year event.
Record drawings were also obtained for Serena Park (Catchments C-70 and C-80) and for
Liberty Lane (Catchment C-330) but these older pipe detention systems from the late 1970's do
not provide substantial detention volume and were not included in the hydrology model of the
basin.
Record drawings for the conveyance system along SE 1441
h Street (King County Department of
Public Works, January 18, 1984) were found to be accurate when checked against field
observations and a recent field survey. The drawings show that tbe 18-inch diameter CMP is
perforated in the upper half of the pipe. According to the plans, the pipe is set in a gravel bed to
allow infiltration. This design encourages infiltration and groundwater recharge by taking
advantage of the relatively flat pipe slope and surrounding outwash soils. While this pipe
configuration provides baseflow benefits to down gradient tributaries of the Cedar River, the
perforations do not provide much flood relief during large flows. Assuming a reasonable
infiltration rate of 10 inches per hour, and a 42-inch wide infiltration surface that extends from
162"d Avenue SE to 1561h Avenue SE, the rate of water infiltrating from the pipe to the native
soil would be roughly 1.5 cubic foot per second. This rate is small relative to the predicted 100-
year flow rate of almost 40 cubic feet per second. While the infiltration component of the
conveyance system has been noted, it was not included in the hydraulic model of the system.
2.2 Hydrology Assessment of Contributing Basins
The hydrologic model KCRTS was used to develop runoff time series for each of the basins
contributing to the SE 1441h Street Conveyance system (Appendix B.l). The reduced I-hour
KCRTS time series data set was used for the Seatac rainfall region with a correction factor of
1.0. The I-hour time series is appropriate for the modeling conducted because flows from a
sizeable portion of the basin are routed through detention ponds. In addition, the KCRTS
modeling methodology neglects attenuation that occurs when time series are routed through the
watershed.
Time series routing through stormwater ponds was conducted to characterize the attenuation
provided by some of the more significant storage areas in the basin, including the stormwater
detention system for Hamilton Place (Catchment C-260), Evendell Plat (Catchment C-230),
Nichols Place (Catchment C-220), and Liberty Grove (Catchments C-240 and 241 ). In addition,
the infiltration stormwater pond for Carolwood was assumed to infiltrate all runoff from
2-5
SE 14.fh Street-June 2007
',
, ...
Basin Map
SE 144th Street Drainage Analysis
King County, Washington
-Sit f Sth-S1re_et
1
I
I I
I
•, I
Hamilton Place
Legend
D R/D
:---·-·1 L _____ J
0
D
Basin Boundary
Type 2 CB
Type 1 CB
Pipe/Culvert
Basin ID
/
/
/
·:o ~ I
I--
I
I' _j . ./.
-LL...~I : -~-
-. -,
C-250 I
: I
~ -
·I ,-.
I I
, ..
Liberty Grove
r-·-1----""l""'----·-·1-
/1
. D Liberty Grove
'\
1 !' :
• I
;-j _ . /
__ _._-;..-.;_-.,~
'Nichol's P,lace · ,
~... /-
1
C-220 10---
, I
Cave11a .,...--....:-£.--
20
. \ \
. --.\-\ ~----·-----~ ,,_ \--
-. ., \, \.~ \ .. , ...
1w l \ \ ~ i~.I C-210 I\ ···,. i ~ \ •
I<( • -· ·-\ '··. J '"··J \ L I -.__ \ '
, --
1
.... 1 ........ \ r-... Lieerty Gar.dens ···,
1(01 •, I '• "~,
\ --
\
i . ~· -
. -r-·---::.--:---_--
i I ,-· 10 1 ·,. ~ ,
. ,----,..... \ \ \ C-80 .... .,, 1 -_.-.
,,,.--------..:.l_.J...i --1~--l...c----~'-\ ·-·· -.· '\ '\ j ~ -1. ' .. '.'.:_::;,-c,. =.t1 ~-~---·-----J_l_ ---r-·-r ---\ . _
C8f01WOO ~---1
i _ ; ~ _, ·C-1~6 I :
() 400
~---~I Feet
I / l I l. I k. i ; t !--I / ,._---==-:\ -I '-., ·. ll~ y
I ! (l 1 ·.., .. -·-····. --·f I ~ 11 .! d ~ -· I I _J ,/l ____ J, !
/1 I I ;' ,_. l ,
25-YR
1
= 19 .08 CFS r 1;~'--l,. 1 · --1 t --
100-YR= 24 .66 CFS : '.. --~--L2:t~:~:J lt. _
_ -==::j_-_ -
---1 I
C-60 -"' j ·--C-90 : --I
·-..--L__c .,_ --,.. -, -_ -::I -=I ---_ -. --,
Ed McCarthy, PE, PS Date: 6/15/07
9957 171 st Ave nue SE
Renton, Washington 98059
Phone: (425 ) 271-5734
Fax : (425) 27 1-3432 Figure 4
Catchment C-106. The stage-storage relationships for these stormwater ponds are listed in
Appendix B.2.
Peak flow rates for the 25-year and l 00-year return periods at key locations in the watershed and
along SE 144th Street are shown in Figure 4. The peak rates associated with the 2-, 10-, 25-, and
100-year return periods at these same locations are listed in Table 2. The major inflow points to
the SE 144th Street conveyance system are at the intersections of 162nd A venue SE and 156th
Avenue SE. A total 100-year flow rate of39.72 cubic feet per second was predicted to flow to
SE 144th Street from contributing basins.
2.3 Hydraulic Analysis of Conveyance System
The conveyance system along SE 144th Street consists primarily of an 18-inch diameter CMP
located along the south side of the road. A ditch and culvert system is located on the north side
of the road. The ditch and culvert system is not continuous along the entire length of SE l 44'h
Street. Rather, it is broken up by segments of road with no conveyance on the north side of the
road. The northerly ditch and culverts are connected to the 18-inch diameter storm pipe by 12-
inch diameter cross culverts at four locations along the conveyance route.
At l 56'h Avenue SE (CB-6), the diameter of the pipe system increase to 24 inches. From CB 6,
the pipe system continues west in the unimproved SE 144th Street right-of-way. At CB 1, the
pipe is conveyed down a steep embankment to 154 1h Place SE and then to an HDPE tightline
down the steep ravine slope to Tributary 0307 (King County Department of Public Works, June
23, 1997).
A detailed field survey of the entire pipe and ditch network, including several road sections, was
conducted by Barghausen Consulting Engineers (June 2007). These data were used to construct
the XP-Storm and HEC-RAS models described below.
The hydraulic model XP-Storm (Version 9) was used to evaluate the 18-inch diameter pipe
conveyance system along the south side of SE 1441h Street. The EXTRAN layer of the model
was utilized, basing hydrologic inputs on flow rates predicted by KCRTS. The XP-Storm
Hydraulics engine solves the complete St. Venant dynamic flow equations for gradually varied,
one dimensional, unsteady flow throughout the drainage network. The calculation accurately
models backwater effects, flow reversal, surcharging, and pressure flow. The model allows for
looped networks, multiple outfalls and accounts for storage in conduits.
The XP-Storm model accounts for pipe friction losses and pipe entrance and exit losses. A
Manning's roughness coefficient of0.024 was assumed in the modeling for CMP and a value of
0.012 was assumed for concrete and plastic pipe. An entrance coefficient of 0.5 and an exit
coefficient of 1 .0 were used at catch basin junction. XP-Storm modeling results for the 25-year
peak flow rate for the conveyance pipe along SE 144 1h Street is provided in Appendix C.
2-7
SE 14¢1' Street June 2007
Table 2. Peak Flow Rates at Key Locations
Location Return Period (Years)
2-Yr (CFS) 10-Yr (CFSl 25-Yr (CFS) 100-Yr (CFSl
CB-18A 9.86 15.70 19.08 24.66
160th Ave SE 11.23 17.65 21.31 27.42
CB-5 11.72 18.37 22.23 28.52
CB-4C 4.25 6.86 8.36 10.86
CB-4 16.09 25.43 30.85 39.72
The hydraulic model HEC-RAS was used to model the roadway surface and ditch conveyance
under flood conditions for the 100-year peak flow rate. The 100-ycar peak rate assumes that 5
cubic feet per second is conveyed in the 18-inch diameter storm pipe along the south side of the
road. The remainder of the flow is assumed to be conveyed in the roadway and roadside ditch.
The roadway conveyance capacity was evaluated from CB-I IA (HEC-RAS Sta 0+00) to the
intersection of 162"d Avenue SE (HEC-RAS Sta 10+10). HEC-RAS analysis of the roadwal
conveyance system for the I 00-year peak rate indicates that the ditch system between 162"
Avenue SE and 160'h Avenue SE has adequate capacity to convey the I 00-year peak rate.
However, driveway culverts along this reach would be overtopped. In addition, the HEC-RAS
model predicted that flow depths would be up to 0.7-foot deep over driveways. HEC-RAS
results are presented in Appendix D.
Roadway flooding along SE 144th Street would be considered as "severe roadway flooding
problem" according to King County standards (King County Department of Natural Resources,
January 2005) due to the following conditions:
• Between the intersection of l 62"d A venue SE and l 60'h A venue SE driveway culverts
along the ditch on the north side of SE l 44'h Street would become overtopped, posing
a threat of unsafe access due to indiscernible driveway edges.
• Floodwater over the driveways on the north side of SE 144th Street between 1601h
Avenue SE and CB-1 IA would be deeper than 0.5 foot, posing a severe impediment
to emergency vehicle access.
2.4 Flooding Locations and Flood Flow Paths
Flows with return periods of 2 to 5 years likely surcharge the 18-inch diameter pipe system.
Flows were predicted to leave the pipe and ditch drainage system at a number of locations
including CB-4C, CB-JOA, CB14A, CB-15A, CB-ISA-I, and CB-18A. Between the intersection
of l 62"d A venue SE and 160 1h A venue SE, overflow from the catch basins is conveyed to the
west in the roadside ditch on the north side of the road. From the intersection at 1601h Avenue
SE, overflow from the catch basins is conveyed to the west mainly along the north side of the
road. Flooding covers the north half of the north travel lane at locations near CB-I IA. From CB-
I I A, floodwater is conveyed further west in the north travel lane until it reaches a low lying area
located north ofCB-9A. Depending upon the magnitude of flows, the floodwater either
2-8
SE 14¢h Street-June 2007
~
,,L
\ I
,I
"-
J... -~ ---~
X X
't \ ,-'
1\ ' ~ j ! Legend
·i
: f--', I I D RID \: I .• ; !
-' 1l ·---\ r-· 1 Basin Boundary ~-\ i ... l _________ :
'1 ~ Flood Flow Path
t 1
'. i Type 2 CB ......
' : 0
D Type 1 CB ~
12_ 18" Pipe/Culvert ,
24" Pipe/Culvert
I C-10 I Basin ID
---...
~::,i,#--~
;~-
I.-"' -••
l
I ,, I
. ~--= -'i
! ,J-~ --I
. -"'-"' 1 "-~-:-i \
w
Cf)
<1)
>
<(
~
(0
l[)
""i i "'"""
I
i 1 I
'--
~
---·r
r I
! I
. -
l
!,.•----
. l .
~
! -
-. __. ----~-
I
I
w
Cf).
(I)
>
<(
£
O •
CD
I
\
\
\
\
\ -
\
\
\_
\
\
\ \---
\
\\ \\ I C-300 I f ""--~ i
I C-210 I ,
-··-
'
\
\
\
\
\
\
\.,
.._ \ ·, •.
\
.\
\
\_
\
\\
\
I
I
t ··., ·,. --, ... ,_
'1,J
1,. __
! \\_ I \ __ ' \ . \
<('-~--==-=-
( ...... ./
\, X
X
~
\,
·/' ,,.~-\
fi
_______ / __ _J_ -, l \.
,q .. -...-,·-·-----· ·-··· I l
(
I
l
(
/
j
/1
I
' _j
.,,
/, I /;: /
!/ -I ,'/ I I;· ;,.
I -1 ·1 ,l1 !
!_1 I '1(:: ///. 1-_, ·
I Ii/ /
/,If' / II' ,,.,, 11 1.\\ I (Ii /,1~111
///
z
',
I 11 \
/I'
/
/ .,~~ ,...,,.... X
.,
'•
\
'x-.....
\ \)
I
1···-·
.,i'
i ' :
!
! ;
CIB-4B
~
j ' .
(,\ I ' I
i i I :
--,
· CB-4 C --
·-i ~ l i
\ \&);))(// l _, ~ \ ~ C6-4A
-,----
DJ T
i
J C -106 1
Likely Flood Area
and Flowpath
', S.= ! •.
C B-1 CB-2 \ j
C B-3 i j rr~:=__~=-=-~:-=--------·==--·----==···\ -+-! CB-5
X
·,I<
',( --4,·
,
,.
1'
"
,"
C B-4 \ ~\-cs-6 -·C B-; CB~Sf : , \,
I• -··1 -, \ I
X I ,_..;:-_____ ---l---------·-·-,------,·-··
I I_ i ~ --~ I ' ' ,/
"'
t--c B-:tl ~--------:--C ~ 1 0. I Q
7 -~ ~---~ 20 I ·, I •
> ~-~ (( {\ ~ll X '-,
-;·-·· 1-t --,
f x· \1
'
I
\
I
(\
'· /-, '
)
\ (
~
I
" \
-1 \
' \
\
I --'<z:-:-~
'<. \ \ • j1 \ I
::::_ -:-:: -.,I--.
,, '\ I ~ ( ~ 1
' I \ , J--.. .J .
! \ ~ ', ~--It I\\
I I :,;, .
i-\~ -
!' ~J \ -
1~--~'
X
\ i
.. f
\
'.
r ·'
I ;
I
_}t
,
;.,? ,,.--
; I /'
I /• / ' . . ,_,-I
I
l X
s E. t42nc1 P;
_------,=
-----.,
'
~-
--~-......
'1
I , I
'·l I
'· t /1·
-,) . '
'
.._.
i , I I / / I \\ (
I I l)/ I
I \ \, ;,
(r'r" l. -~ l t0.
,
...J ---
I C-54 1
\I
·\
'1
I
\
'·
\
\
: '
i ' ·' ! / I X
I
J
I
I • ( ., -'·~,·l
i
I
I c200 /I
I,-,
;
t
/
/
/
/
_/
\
!
_i
_i
i
,•
I --=--c-..;.-;a_.-==--T~-
~B-~ X /I ~B~~~:
• . / r> ; \
I \ / -
•/ 4 I '\__,
"' --_.,-i
.: / '
i<
~->
i/
( "";>'
,, l X ' ' . ,,
·: \ \ \ / \ \ I
I
'-'
I
-' f 'i ·~ / ''\ l
r---
~
LO
~ co
2
~
LO
~ :,
C>
LL
..-N "''"' ~ :1 ...... NN
~~ NN ~~
iv
C: --
0 " ii: if
~
0
UJ <X) en a,
2!
"'C:
.ic ~ -"' f!_ ?;_
~ C: ... _g
.,., C:
8l ~
-Q)
Q)
LL
0
0
N
()
E -~
Cl) en
-.z:. II) cu
>, C
(JJ <(
Cl) ~ (.) cu
C: -~ ca ~ >-o Q) > C:
0
(.) Q)
• Q) -.._ en u5
.s:: ..c. -..... 3~
""'" UJ w Cf)
(JJ
C
0
Ol
C
..c. en cu
~
;:;,
C
:::,
0 u
O>
C
~
infiltrates at this location outside the road right-of-way or continues to flow to the Carolwood
infiltration pond. Flows larger than approximately IO to 15 cubic feet per second likely do not
reach beyond CB 5 (located at the intersection of 160 1
h Avenue SE and SE 1441
h Street), within
either the pipe or roadway.
2-10
SE J 4,th Street -June. 2007
3. DRAINAGE MITIGATION OPTIONS
The following four concepts were developed to mitigate for the proposed developments' impacts
of downstream flooding:
• Providing onsite detention to King County Level 3 flow control standards
• Providing offsite conveyance system upgrades (Offsite Option 1)
• Providing offsite conveyance system upgrades and infiltration (Offsite Option 2)
• Providing offsite conveyance system upgrades and infiltration by implementing
bioretention (Offsite Option 3)
3.1 Onsite Level 3 Detention
Level 2 stormwatcr detention standards are required for the Threadgill, Liberty Gardens, and
Cavella developments. When downstream severe roadway flooding is of concern, Level 3
stormwater detention standards are often included in the drainage design for new development as
a stormwater mitigation. Providing this type of mitigation has been used with success on several
projects in King County.
Level 3 detention standards would likely adequately mitigate the impacts of flooding from the
proposed projects on downstream flooding. Adequately mitigating the flooding problem, at
minimum, requires that runoff from the projects not aggravate the existing level or duration of
flooding nor create new flooding.
Adopting this strategy as a mitigation has several advantages that appeal to developers. Because
the mitigation is entirely onsite, the developer has control of its design and implementation. No
easements, consents, or coordination with downstream property owners is required. The
mitigation is typically easy to implement because it is simply a matter of enlarging the already
proposed Level 2 stormwatcr facility. This type of mitigation particularly makes sense where the
proposed development is small relative to the surrounding basin and the required downstream
upgrades are either logistically difficult or overly expensive to implement.
The main disadvantage to providing Level 3 detention as a flooding mitigation is that while
existing problems are typically not aggravated, the problems are not solved either.
3.2 Offsite Conveyance Improvements
Offsitc mitigation Option 1 would include improving the conveyance system along the north side
of SE l 44'h Street (Figure 6). Between 162nd Avenue SE and l 60'h Avenue SE this would entail
upsizing driveway culverts and re-grading and cleaning open sections of the existing roadside
ditch. From l 60'h Avenue SE to 156th Avenue SE, a distance of about 1,300 feet, an 18-inch
diameter storm pipe would be constructed to increase conveyance capacity.
3-1
SE 14,f" Street-June 2007
Option 1 -Conveyance
B-4B L,r-LJ CB-4C ·
w
If)
(1)
:::i
CB-4A Q ~,
>" <(
.c
<D
CB-3 l!_, CB-5 _ . -, --·· v
CB-1 CB-2
-~
'
--·--·-1
18" Conveyance i
Pipe I Y ;:,-,,
/
if--------
.. CB-110 CB-15A ,
Ditc h/C ulvert
Upgrades
i i
'W i /(I) .
: (1) / ! :::i :
'C / I (1). . : >. /
. J<( . / '-0 / ! C .-,,·
:N ./ . r · r
j
~ I CB-4
CB-6 CB-7 CS:-8 CB~9 CB-1 0
c ~ . c1511c c§\~.15A~ _ / ~ ' -~ . s;: ~? -. "L_ -·
' 'I Cr ,:J D {_ .. -. -L ~ /, ..
CB-1 1 CB-12 :cB-13 CB-14 CB-1 5
''
. _ c~::4s :[o-CB-4 8
I I
Option 2 -Conveyance/Infiltration
\ CB-1 CB-2
·r·, ____ ·_,_ '. ·, .,-
'"' ' .
"
' \'\. --
\ \
CB-3
; _______ J
·----
'·
r·----!
__ L
C B-i
! ___ ,"-
j
CB-~-
I
j CB-6;
I .
' I L __
12" Overflow
Pipe
---l
1CB-7 : CB=-s -----·-
! r
I
i
--·-------!
C-B-Si" -----cS:.1 O '
1··
; ·~· ·-· ---i
i
''
/CB-11
·---·-
L. ---
'
I ,
I
. '1-8" Conveyance
: J Pipe
I ,
i, I !I
CBt 12
i
'
~B-110 , _ __ ce -1-1g &,;
!CB-1r C~-14 t ;-1]
I I i
I !
I
I I : i i
J I • I t-· ---------1 ----~ -_· --=
CB-16 SE 144t h St , CB-17 CB-18
CB-16
D itch/C ulve rt
Upg rades
"---Cl=
--
!
'jw
:(I)
l (l)
::::i
j c
,(1) / ·> .·
I <( /
iu /
·C / 'N .· r~;
SE 144th St ·c B-17 iCB-18
I
/
r --. -··-· 1'---,.
/ ·,._
-~===,.-,-,. _______ ---;if --
I ' //j ·--, ___ I ' ! ..... __ l
CB-19
I
i
i
;
cfo -19
' /
l
'
'
--,----,1 ' I ' I ' ! '-, __ _,-, -----I ----~· ;-(-i ' 1-------1-11 i . i I !I. ! ! I I ·-------I ' \ ',, __ I
•. -I I I I I I i ' / i , \ '. I / 'I l l I I ' .. . I ' I . t t · -· -. I ' . / ' ' ' I Option 3 -81ore en ion l-4B : -es-:4e-_______ l_ ____ c._ 1___ ) --___ i __ __L ____ :_ -·--·< / ! : , : \ 1 ~ •
I/ / I I r __ -J IJ -. -1----------· . --·I;,--· -------,----1---·-r -··-fl --':-,::, _-_-·_-__ ii I -·-··----L . -" ',\' ~·-·-· a //
i
\
i
i
\ i
I f · f I ; I<;:' Bi o rete ntion , 8" D ia. , : / I '\ _. r
I
I I
I. .., I CB-4A · ;,I Ce lls • Nalive Pla n ls _.. Fulverts I. _ 1 .. ~ L __ __ -~--__ _ ~ __ _
1 I, I I «>r--··-r1 a nd Overflow , -------r
1
, I I I --
' .;/ ' ' I I
\ ! ~[-_1 _____ c~s -2 ____ ce~-I ___ 1~j ce J.. I . • I I t~-)6D · . :~---
,------.---~-
C B~ cs7 -Jc~ C~:s-· -'\ CB-1 6 -----' I I ! I I
\~\
·---------\ -------r
' ' I ' ' -t \\ \
\,\ ' )_. --. ' --\'·~-,. \ I j I
----c '> r -1 __ _[_1 __ .J -~i _ ~,,. 1' ' ', __ ,,_. \~ ' '
'~-'~-}:\ . \ \, ' .,,,-"\ :-ij-:::,,;,; ' ' \.}: "-: .
.,---·1 --. ·-1-~ -·~----
l'CB-17 iCB-1 8 1 ri'B-19 I
1
1 1 . , r 1
I I I / f --·--I., t ; / ·~ \. ~--'\'
,-...
a
~
<D
2
('J
0
0
0
N
(.0
(1) ...
:J
.!?
LL
~~
ti:>~ ;::. ;::.
N N
Co~ """' ~~
~ X
tE. .:J'.
$
0 LJ.J"'
"' 0, ~i
<lJ" ~~
E~ ,-... --" ,-... 2
ffi &
......
Q.)
Q.)
LL
[
1/) -~
C: >,
0 ro
•-C
-<(
C
a. (1) .B
0 gi
Ol
C
C: -~ i:
0 ~ If)
ro
·-0 s .....
C't'I ii,
.2> C
:::i ..... -0
·-(1) :: i 0
Ol
(1) (f) C
..... .c ::Z ·--1/) "q" ~ :! o w
(/)
Similar to the pipe system on the south side of the road, the possibility of including sections of
perforated pipe embedded in drain rock on the north side of the road should be investigated.
Issues such as the impact of infiltrated water on the structural integrity of the road base and
surrounding properties should be evaluated by a geotechnical engineer.
3.3 Offsite Conveyance Improvements/Infiltration
As with Option 1, offsite mitigation Option 2 would include improving the conveyance system
along the north side of SE 144th Street. Between 162"<l Avenue SE and 160th Avenue SE this
would entail upsizing driveway culverts and re-grading and cleaning open sections of the
existing roadside ditch. From 160'h Avenue SE, an 18-inch diameter storm pipe would be
constructed to convey stormwater to an infiltration pond located about 600 feet west of l 60'h
Avenue SE. An overflow structure from the pond would tic into the existing 18-inch diameter
storm pipe on the south side of SE 144th Street.
The proposed location of the infiltration pond is a large lot with a smaller single-family
residential structure on it. The lot could perhaps be subdivided with the vacant tract being
purchased by the County. The pond site is likely within the current flood flow path of larger
storms (Figure 5).
The infiltration characteristics of the pond site are likely favorable, as has been noted with the
successful operation of the pond at Carolwood for several years. The infiltration pond would
take advantage of the high infiltration rates of the underlying outwash soils and would reduce the
flow rates to the storm pipe downstream from the pond. Environmental benefits of the system
would include improving water quality and increasing groundwater recharge to the benefit of
down gradient tributaries of the Cedar River.
3.4 Bioretention along SE 144th Street
Offsite mitigation Option 3 would entail constructing bioretention swales within the right-of-way
along the north side of SE 144th Street (Figure 6). Bioretention is a commonly applied low
impact development (LID) strategy that has also been used with great success in improving
roadway drainage in established neighborhoods. Seattle's Soft Edge Alternative streets (SEA-
streets) have been shown to substantially reduce stormwater runoff and improve neighborhood
aesthetics.
To manage stormwater runoff along SE 144'h Street, a series ofbioretention cells would be
constructed in place of the existing northerly ditch and culvert system. Each bioretention system
would be configured with an engineered soil media, a gravel infiltration trench, an overflow
control, and a conveyance pipe/driveway culvert linking the cells together. In addition, each cell
would be landscape with native plants.
The bioretention cells would take advantage of the high infiltration rates of the underlying
outwash soils and would also increase conveyance capacity for higher flow rates. Environmental
benefits of the system would include improving water quality and increasing groundwater
3-3
SE J 4.(h Street-June 2007
recharge to the benefit of down gradient tributaries of the Cedar River. In addition, the
bioretention cells would improve the aesthetics of the neighborhood and also provide shade.
Disadvantages of the bioretention system would include disrupting existing landscaping of
property owners and reducing street parking.
3-4
SE 14¢1' Streer June 2007
4. KEY RESULTS AND RECOMMENDATIONS
4.1 Key Results
The following conclusions can be drawn based on the hydrologic and hydraulic analysis
conducted for the conveyance system along SE 144 th Street presented in the preceding sections
of this report:
• The three proposed developments (Threadgill Plat, Liberty Gardens, and Cavella)
collectively represent IO percent of the study area basin.
• While calculations presented in this report suggest that the conveyance system along SE
144th Street is undersized, there are no drainage complaints on record that support this.
Physical evidence of flooding has been documented at the intersection of 162nd Avenue
SE and SE 144 1h. Drainage improvements have also recently been constructed by King
County Roads Division at the intersection of 1601h Avenue SE and SE 1441h Street, likely
in attempt to collect overflow from the catch basins at that location.
• The 18-inch diameter pipe along SE 144 1
h Street has a capacity of 4 to 6 cubic feet per
second. The roadway and ditch system along the north side of the road convey the
majority of higher flows.
• HEC-RAS analysis of the roadway conveyance system for the 100-year peak rate
indicates that the ditch system between 162nd Avenue SE and 160 1h Avenue SE has
adequate capacity to convey the I 00-year peak rate. However, driveway culverts along
this reach would be overtopped.
• Flows with return periods of2 to 5 years likely surcharge the 18-inch diameter pipe
system and flood the intersection of 1601
h Avenue SE and SE 1441h Street. Overflow from
the catch basins is likely conveyed in the roadway until it reaches a low lying area
located north of CB 9. Depending upon the magnitude of flows, the floodwater either
infiltrates at this location outside the road right-of-way or continues to flow to the
Carolwood infiltration pond.
• Four flood mitigation concepts were presented and discussed including increased onsite
detention and three offsite mitigation options.
4.2 Recommendations
Any one of the four proposed drainage mitigations would adequately meet the intent of the King
County Surface Water Design Manual (January 2005) Core Requirements. Offsite mitigation
Options 2 and 3 would provide the most benefit to the downstream system in terms of
stormwater management and environmental advantages. While onsite stormwater mitigation
would perhaps the easiest and least expensive option to implement, the downstream flooding
problem would not be solved.
4-1
SE I 44"' Street-June 2007
Implementing the offsite mitigations would require King County's leadership, and even
ownership of the project. This would be especially true for offsite Options 2 and 3, where a
vacant parcel would need to be acquired (for Option 2) or the right-of-way would need to be
substantially re-graded (for Option 3).
For any of the offsite options to be adopted, the County would need to see value in solving
drainage problems along SE 1441h Street and in the environmental benefits provided by these
designs. Providing bioretention through SEA-streets and the like, to solve existing and potential
future drainage problems, should be a consideration for the County. To my knowledge, the
County has not implemented a project similar to Option 3, and this would be a suitably-scaled
pilot project.
For these offsite options to be implemented, each developer would likely make a fair and
reasonable contribution to the project. The County would be responsible for designing and
implementing the project.
4-2
SE 144"'Street-June2007
5. REFERENCES
Baima & Holmberg, Inc. and Ed McCarthy, PE, PS. November 18, 2005. Level 1 Downstream
Drainage Analysis for Threadgill Plat. Issaquah, Wash.
Barghausen Consulting Engineers, June 2003. Hamilton Place -Technical Information Report.
Kent, Wash.
Daley-Morrow-Poblete, Inc., February 2003. Liberty Grove -Technical Information Report.
French, Richard, H., 1985. Open-Channel Hydraulics. McGraw-Hill Book Company. New
York.
Haozous Engineering, PS. May 2003. Nichol's Place -Preliminary Technical Information Report.
Mukilteo, Wash.
Haozous Engineering, PS. June 15, 2001. Evendell Plat -Preliminary Technical Information
Report. DOES File No. L98P0047. Renton, Wash.
King County Department of Natural Resources, 1997. Lower Cedar River Basin and Nonpoint
Pollution Action Plan. Seattle.
King County Department of Natural Resources, 1993. Current & Future Conditions Report for
the Cedar River. Seattle.
King County Department of Parks, Planning, and Resources, 1990. Sensitive Areas Map Folio.
Seattle.
King Countr Department of Public Works, January 18, 1984. SE 144th Street-156'h Ave. SE to
1641 Pl SE. Sheets I -8. Seattle.
King County Department of Public Works, June 23, 1997.1541h Place SE Slope Stabilization
Project. Sheets I -13. Seattle.
King County Department of Natural Resources, January 2005. King County Surface Water
Design Manual. Seattle.
U.S. Department of Agriculture, Soil Conservation Service, 1973. Soil Survey of King County
Area, Washington.
5-1
SE I 44'n Street-June 2007
Appendices
Appendix A. Photographs of the Downstream System
Appendix B. KCRTS Documentation for Contributing Basins
Appendix C. XP-SWMM Model Results
Appendix D. HEC-RAS Analysis of Roadway Conveyance
SE J 4,th Street-June 2007
Appendix A: Photos of the Downstream System
T Photo Number 1 T Photo Number 2
Date of Photo: 1 -11-06 (Source: Dave Petric) Date of Photo: 1-21-06 (Source: Dave Petrie)
Location: South of CB 18A, looking north.
Description: Overflowing pond during height of rainstorm.
Location: North of CB 18A , looking south.
Description: Pond north of SE 144th Street within the 162 110
Water is flowing to the roadside ditch on the
north side of SE 144 th Street.
right-of-way during a light storm.
Appendix B. KCRTS Documentation for Contributing Basins
Appendix B.1 KCRTS Time Series Calculations
Appendix B.2 KCRTS Pond Designs
Appendix B.3 KCRTS Peak Flow Rates
B-1
SE 14,(h Street-June 2007
Appendix 8.1. KCRTS Time Series Calculations
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Project Location: Sea-Tac
Computing Series c-10.tsf
Regional Scale Factor: 1.00
Data Type : Historic
Creating Hourly Time Series File
Outwash Pasture
Outwash Grass
Impervious
Loading Time Series File:C:\KC SWDM\KC DATA\STOP60H.rnf
0.16 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STOG60H.rnf
0. 2 9 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
0.08 acres
Total Area 0.53 acres
Peak Discharge: 0.071 CFS at 16:00 on Mar 3 in 1950
Storing Time Series File:c-10.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Corrunand
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-10.tsf
LogPearson III Coefficients
Time Series File:c-10.tsf
Project Location:Sea-Tac
Mean~ -1.641 StdDev~ 0.141
Skew~ 1.196
Frequencies & Peaks saved to File:c-10.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-10.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-10.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Corrunand
CREATE a new Time Series
Production of Runoff Time Series
B-2
SEJ4,t/'Street-June2007
Project Location: Sea-Tac
Computing Series c-20.tsf
Regional Scale Factor: 1.00
Data Type : Historic
Creating Hourly Time Series File
Outwash Pasture
Outwash Grass
Impervious
Loading Time Series File:C:\KC SWDM\KC DATA\STOP60H.rnf
0.30 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STOG60H.rnf
1.05 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
0.51 acres
Total Area 1.86 acres
Peak Discharge: 0.331 CFS at 16:00 on Mar 3 in 1950
Storing Time Series File:c-20.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-20.tsf
LogPearson III Coefficients
Time Series File:c-20.tsf
Project Location:Sea-Tac
Mean= -0.857 StdDev= 0.119
Skew= 0. 941
Frequencies & Peaks saved to File:c-20.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-20.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-20.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Project Location : Sea-Tac
Computing Series c-30.tsf
Regional Scale Factor : 1.00
Data Type : Historic
Creating Hourly Time Series File
Outwash Pasture
Loading Time Series File:C:\KC SWDM\KC DATA\STOP60H.rnf
0.31 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STOG60H.rnf
B-3
SE J 44'n Street-June 2007
Outwash Grass
Impervious
0.91 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
0. 41 acres
Total Area 1.63 acres
Peak Discharge: 0.276 CFS at 16:00 on Mar 3 in 1950
Storing Time Series File:c-30.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Time Series File:c-30.tsf
Project Location:Sea-Tac
Loading Stage/Discharge curve:c-30.tsf
LogPearson III Coefficients
Mean~ -0.949 StdDev~ 0.121
Skew~ 0.973
Frequencies & Peaks saved to File:c-30.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-30.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-30.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Project ~ocation : Sea-Tac
Computing Series c-40.tsf
Regional Scale Factor: 1.00
Data Type : Historic
Creat.ing Hourly Time Series File
Loading Time Series File:C:\KC SWDM\KC DATA\STOG60H.rnf
Outwash Grass 0.26 acres
Impervious
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
0.30 acres
Total Area 0.56 acres
Peak Discharge: 0.145 CFS at 16:00 on Mar 3 in 1950
SE 14.f' Street-June 2007
Storing Time Series File:c-40.tsf
Time Series Computed
KCRTS Command
B-4
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Time Series File:c-40.tsf
Project Location:Sea-Tac
Loading Stage/Discharge curve:c-40.tsf
LogPearson III Coefficients
Mean~ -1.104 StdDev~ 0.105
Skew~ 0.664
Frequencies & Peaks saved to File:c-40.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-40.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-40.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
of Runoff Time Series
Project Location :
Production
Sea-Tac
c-42.tsf
1. 00
Computing Series
Regional Scale Factor:
Data Type : Historic
Creating Hourly Time Series File
Loading Time Series File:C:\KC SWDM\KC DATA\STOP60H.rnf
Outwash Pasture 0.03 acres
Outwash Grass
Impervious
Loading Time Series File:C:\KC SWDM\KC DATA\STOG60H.rnf
0.96 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
0.67 acres
Total Area 1.66 acres
Peak Discharge: 0.373 CFS at 16:00 on Mar 3 in 1950
SE 144'h Street-June 2007
Storing Time Series File:c-42.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
B-5
Flow Frequency Analysis
Loading Stage/Discharge curve:c-42.tsf
LogPearson III Coefficients
Time Series File:c-42.tsf
Project Location:Sea-Tac
Mean~ -0.747 StdDev~ 0.110
Skew~ 0.794
Frequencies & Peaks saved to File:c-42.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-42.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-42.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Project Location: Sea-Tac
Computing Series c-44.tsf
Regional Scale Factor : 1.00
Data Type: Historic
Creating Hourly Time Series File
Impervious
Loading Time Series File:C:\KC_SWDM\KC DATA\STEI60H.rnf
0.99 acres
Total Area 0.99 acres
Peak Discharge: 0.408 CFS at 0:00 on Oct 6 in 1981
Storing Time Series File:c-44.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-44.tsf
LogPearson III Coefficients
Time Series File:c-44.tsf
Project Location:Sea-Tac
Mean~ -0.596 StdDev~ 0.096
Skew~ 0.562
Frequencies & Peaks saved to File:c-44.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-44.tsf
B-6
SE 14,th Street-June 2007
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-44.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
of Runoff Time Series
Project Location:
Production
Sea-Tac
c-50.tsf
1. 00
Computing Series
Regional Scale Factor:
Data Type: Historic
Creating Hourly Time Series File
Impervious
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
0.51 acres
Total Area 0.51 acres
Peak Discharge: 0.210 CFS at 0:00 on Oct 6 in 1981
Storing Time Series File:c-50.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-50.tsf
LogPearson III Coefficients
Time Series File:c-50.tsf
Project Location:Sea-Tac
Mean~ -0.884 StdDev~ 0.095
Skew-0.562
Frequencies & Peaks saved to File:c-50.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-50.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-50.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
B-7
SE 14,tn Street-June 2007
Project Location :
Production of Runoff Time Series
Sea-Tac
Computing Series
Regional Scale Factor :
c-52.tsf
1. 00
Data Type : Historic
Creating Hourly Time Series File
Till Pasture
Till Grass
Outwash Pasture
Outwash Grass
Impervious
Loading Time Series File:C:\KC SWDM\KC DATA\STTP60H.rnf
0.01 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STTG60H.rnf
0.80 acres
Loading Time Series File:C:\KC_SWDM\KC_DATA\STOP60H.rnf
0.01 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STOG60H.rnf
0.80 acres
Loading Time Series File:C:\KC_SWDM\KC_DATA\STEI60H.rnf
1.15 acres
Total Area 2.77 acres
Peak Discharge: 0.701 CFS at 16:00 on Mar 3 in 1950
Storing Time Series File:c-52.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Conunand
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Time Series File:c-52.tsf
Project Location:Sea-Tac
Loading Stage/Discharge curve:c-52.tsf
LogPearson III Coefficients
Mean~ -0.457 StdDev~ 0.118
Skew~ 0.538
Frequencies & Peaks saved to File:c-52.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-52.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-52.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Project Location : Sea-Tac
Computing Series : c-54.tsf
B-8
SE I 44'h Street-June 2007
Regional Scale Factor : 1.00
Data Type : Historic
Creating Hourly Time Series File
Till Forest
Till Pasture
Till Grass
Outwash Forest
Outwash Pasture
Outwash Grass
Impervious
Loading Time Series File:C:\KC SWDM\KC DATA\STTF60H.rnf
0.03 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STTP60H.rnf
0.03 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STTG60H.rnf
0.83 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STOF60H.rnf
0.04 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STOP60H.rnf
0.04 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STOG60H.rnf
1.24 acres
Loading Time Series File:C:\KC SWDM\KC_DATA\STEI60H.rnf
1.44 acres
Total Area 3.65 acres
Peak Discharge: 0.876 CFS at 16:00 on Mar 3 in 1950
Storing Time Series File:c-54.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Corrunand
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-54.tsf
LogPearson III Coefficients
Time Series File:c-54.tsf
Project Location:Sea-Tac
Mean~ -0.367 StdDev~ 0.117
Skew~ 0.588
Frequencies & Peaks saved to File:c-54.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Computing Interval Locations
Computing Flow Durations
Loading Time Series File:c-54.tsf
Durations & Exceedence Probabilities to File:c-54.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Corrunand
CREATE a new Time Series
Production of Runoff Time Series
Project Location: Sea-Tac
Computing Series : c-60.tsf
B-9
SE 144'1' Street-June 2007
Regional Scale Factor : 1.00
Data Type : Historic
Creating Hourly Time Series File
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
Impervious 0.52 acres
Total Area 0.52 acres
Peak Discharge: 0.214 CFS at 0:00 on Oct 6 in 1981
Storing Time Series File:c-60.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-60.tsf
LogPearson III Coefficients
Time Series File:c-60.tsf
Project Location:Sea-Tac
Mean--0.876 StdDev-0.096
Skew-0.561
Frequencies & Peaks saved to File:c-60.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-60.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-60.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Project Location : Sea-Tac
Computing Series c-70.tsf
Regional Scale Factor : 1.00
Data Type : Historic
Creating Hourly Time Series File
Till Pasture
Till Grass
Outwash Pasture
Outwash Grass
SE 144'" Streel--June 2007
Loading Time Series File:C:\KC SWDM\KC DATA\STTP60H.rnf
0.51 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STTG60H.rnf
1. 70 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STOP60H.rnf
0.34 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STOG60H.rnf
1.13 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
B-10
Impervious 1.34 acres
Total Area 5.02 acres
Peak Discharge: 1.06 CFS at 16:00 on Mar 3 in 1950
Storing Time Series File:c-70.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Time Series File:c-70.tsf
Project Location:Sea-Tac
Loading Stage/Discharge curve:c-70.tsf
LogPearson III Coefficients
Mean= -0.327 StdDev= 0.133
Skew= 0.509
Frequencies & Peaks saved to File:c-70.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-70.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-70.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
of Runoff Time Series
Project Location :
Production
Sea-Tac
c-80.tsf
1. 00
Computing Series
Regional Scale Factor :
Data Type: Historic
Creating Hourly Time Series File
Till ForesL.
Till Pasture
Till Grass
Outwash Forest
Outwash Pasture
Outwash Grass
SE J 4.(h Street -June 2007
Loading Time Series File:C:\KC SWDM\KC DATA\STTF60H.rnf
5.28 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STTP60H.rnf
0.12 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STTG60H.rnf
4.35 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STOF60H.rnf
0.59 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STOP60H.rnf
0.01 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STOG60H.rnf
0.48 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
B-11
Impervious 3.40 acres
Total Area 14.23 acres
Peak Discharge: 2.61 CFS at 6:00 on Jan 9 in 1990
Storing Time Series File:c-80.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-80.tsf
LogPearson III Coefficients
Time Series File:c-80.tsf
Project Location:Sea-Tac
Mean= 0.090 StdDev= 0.131
Skew= 0.500
Frequencies & Peaks saved to File:c-80.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-80.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-80.dur
Analysis Tools Corrunand
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Project Location : Sea-Tac
Computing Series c-90.tsf
Regional Scale Factor: 1.00
Data Type : Historic
Creating Hourly Time Series File
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
Impervious 0.40 acres
Total Area 0.40 acres
Peak Discharge: 0.165 CFS at 0:00 on Oct 6 in 1981
SE l 4¢h Street-June 2007
Storing Time Series File:c-90.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
B-12
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-90.tsf
LogPearson III Coefficients
Time Series File:c-90.tsf
Project Location:Sea-Tac
Mean~ -0.989 StdDev~ 0.096
Skew~ 0.559
Frequencies & Peaks saved to File:c-90.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-90.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-90.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Project Location : Sea-Tac
Computing Series c-100.tsf
Regional Scale Factor: 1.00
Data Type: Historic
Creating Hourly Time Series File
Till Forest
Till Pasture
Till Grass
Impervious
Loading Time Series File:C:\KC SWDM\KC DATA\STTF60H.rnf
0.45 acres
Loading Time Series File:C:\KC_SWDM\KC DATA\STTP60H.rnf
0.33 acres
Loading Time Series File:C:\KC SWDM\KC_DATA\STTG60H.rnf
0.61 acres
Loading Time Series File:C:\KC_SWDM\KC_DATA\STEI60H.rnf
0.17 acres
Total Area 1.56 acres
Peak Discharge: 0.250 CFS at 16:00 on Mar 3 in 1950
Storing Time Series File:c-100.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-100.tsf
LogPearson III Coefficients
B-13
SE J 44n Street-June 2()()7
Time Series File:c-100.tsf
Project Location:Sea-Tac
Mean~ -1.001 StdDev~ 0.167
Skew~ 0.401
Frequencies & Peaks saved to File:c-100.pks
Analysis Tools Cormnand
Compute Flow DURATION and Exceedence
Loading Time Series File:c-100.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-100.dur
Analysis Tools Cormnand
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Project Location : Sea-Tac
Computing Series c-106.tsf
Regional Scale Factor: 1.00
Data Type: Historic
Creating Hourly Time Series File
Till Forest
Till Pasture
Till Grass
Outwash Pasture
Outwash Grass
Impervious
Loading Time Series File:C:\KC SWDM\KC DATA\STTF60H.rnf
2.50 acres
Loading Time Series File:C:\KC_SWDM\KC DATA\STTP60H.rnf
0.12 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STTG60H.rnf
3.34 acres
Loading Time Series File:C:\KC_SWDM\KC DATA\STOP60H.rnf
0.12 acres
Loading Time Series File:C:\KC_SWDM\KC DATA\STOG60H.rnf
3.34 acres
Loading Time Series File:C:\KC SWDM\KC_DATA\STEI60H.rnf
4.64 acres
Total Area 14.06 acres
Peak Discharge: 3.02 CFS at 16:00 on Mar 3 in 1950
Storing Time Series File:c-106.tsf
Time Series Computed
KCRTS Corrunand
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Time Series File:c-106.tsf
Loading Stage/Discharge curve:c-106.tsf
LogPearson III Coefficients
Mean= 0.164 StdDev~ 0.122
B-14
SE 14.f" Street-June 2007
Project Location:Sea-Tac Skew~ 0. 511
Frequencies & Peaks saved to File:c-106.pks
Analysis Tools Cormnand
Compute Flow DURATION and Exceedence
Loading Time Series File:c-106.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-106.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Cormnand
CREATE a new Time Series
Production of Runoff Time Series
Project Location : Sea-Tac
Computing Series c-110.tsf
Regional Scale Factor: 1.00
Data Type : Historic
Creating Hourly Time Series File
Till Forest
Till Pasture
Till Grass
Impervious
Loading Time Series File:C:\KC SWDM\KC DATA\STTF60H.rnf
6.43 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STTP60H.rnf
12.24 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STTG60H.rnf
12.33 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
7.10 acres
Total Area 38.10 acres
Peak Discharge: 6.91 CFS at 6:00 on Jan 9 in 1990
Storing Time
Time Series Computed
Series File:c-110.tsf
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Cormnand
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-110.tsf
LogPearson III Coefficients
Time Series File:c-110.tsf
Project Location:Sea-Tac
Mean== 0.487 StdDev~ 0.145
Skew~ 0. 484
SE 144h Street-June 2007
Frequencies & Peaks saved to File:c-110.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
B-15
Loading Time Series File:c-110.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-110.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Project Location : Sea-Tac
Computing Series c-120.tsf
Regional Scale Factor : 1.00
Data Type : Historic
Creating Hourly Time Series File
Loading Time Series File:C:\KC SWDM\KC DATA\STTP60H.rnf
Till Pasture 0.58 acres
Impervious
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
1.00 acres
Total Area 1.58 acres
Peak Discharge: 0.466 CFS at 6:00 on Jan 9 in 1990
Storing Time
Time Series Computed
Series File:c-120.tsf
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-120.tsf
LogPearson III Coefficients
Time Series File:c-120.tsf
Project Location:Sea-Tac
Mean~ -0.565 StdDev~ 0.101
Skew~ 0. 47 5
Frequencies & Peaks saved to File:c-120.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-120.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-120.dur
SE 14,th Street---June 2007
Analysis Tools Command
RETURN to Previous Menu
B-16
KCRTS Conunand
CREATE a new Time Series
Production of Runoff Time Series
Project Location : Sea-Tac
Computing Series c-130.tsf
Regional Scale Factor : 1.00
Data Type: Historic
Creating Hourly Time Series File
Loading Time Series File:C:\KC SWDM\KC DATA\STTF60H.rnf
Till Forest 2.49 acres
Till Pasture
Till Grass
Impervious
Loading Time Series File:C:\KC SWDM\KC DATA\STTP60H.rnf
7.12 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STTG60H.rnf
5.80 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
1.58 acres
Total Area 16.99 acres
Peak Discharge: 2.64 CFS at 16:00 on Mar 3 in 1950
Storing Time Series File:c-130.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-130.tsf
LogPearson III Coefficients
Time Series File:c-130.tsf
Project Location:Sea-Tac
Mean= 0.015 StdDev-0.175
Skew-0.324
Frequencies & Peaks saved to File:c-130.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-130.tsf
Computing Interval Locations
Computing Flow Durations
SE 144'~ Street June 2007
Durations & Exceedence Probabilities to File:c-130.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
B-17
Project Location: Sea-Tac
Computing Series c-200.tsf
Regional Scale Factor: 1.00
Data Type : Historic
Creating Hourly Time Series File
Loading Time Series File:C:\KC SWDM\KC DATA\STTF60H.rnf
Till Forest 4.45 acres
Till Pasture
Till Grass
Impervious
Loading Time Series File:C:\KC SWDM\KC DATA\STTP60H.rnf
0.14 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STTG60H.rnf
1.79 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
1.18 acres
Total Area 7.56 acres
Peak Discharge: 1.12 CFS at 6:00 on Jan 9 in 1990
Storing Time
Time Series Computed
Series File:c-200.tsf
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Corrunand
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-200.tsf
LogPearson III Coefficients
Time Series File:c-200.tsf
Project Location:Sea-Tac
Mean~ -0.308 StdDev~ 0.145
Skew~ 0.500
Frequencies & Peaks saved to File:c-200.pks
Analysis Tools Corrunand
Compute Flow DURATION and Exceedence
Loading Time Series File:c-200.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-200.dur
Project Location :
Computing Series
Regional Scale Factor:
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Sea-Tac
c-210.tsf
1. 00
Data Type: Historic
Creating Hourly Time Series File
Loading Time Series File:C:\KC SWDM\KC DATA\STTF60H.rnf
B-18
SE I 44'n Street June 2007
Till Forest
Till Pasture
Till Grass
Impervious
3.31 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STTP60H.rnf
1.70 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STTG60H.rnf
4.60 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
2.93 acres
Total Area 12.54 acres
Peak Discharge: 2.47 CFS at 6:00 on Jan 9 in 1990
Storing Time Series File:c-210.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-210.tsf
LogPearson III Coefficients
Time Series File:c-210.tsf
Project Location:Sea-Tac
Mean= 0.056 StdDev~ 0.136
Skew~ 0.482
Frequencies & Peaks saved to File:c-210.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-210.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-210.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Project Location :
Production of Runoff Time Series
Sea-Tac
Computing Series
Regional Scale Factor :
c-220.tsf
1. 00
Data Type: Historic
Creating Hourly Time Series File
Till Grass
Loading Time Series File:C:\KC SWDM\KC DATA\STTG60H.rnf
1.56 acres
Impervious
Loading Time Series File:C:\KC_SWDM\KC DATA\STEI60H.rnf
1.90 acres
Total Area 3.46 acres
Peak Discharge: 1.09 CFS at 6:00 on Jan 9 in 1990
B-19
SE J 4.fh Street-June 2007
Storing Time Series File:c-220.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-220.tsf
LogPearson III Coefficients
Time Series File:c-220.tsf
Project Location:Sea-Tac
Mean~ -0.235 StdDev~ 0.114
Skew~ 0.400
Frequencies & Peaks saved to File:c-220.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-220.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-220.dur
Analysis Tools Conunand
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production
Sea-Tac
c-230.tsf
1. 00
of Runoff Time Series
Project Location:
Computing Series
Regional Scale Factor:
Data Type : Historic
Creating Hourly Time Series File
Till Pasture
Loading Time Series File:C:\KC SWDM\KC DATA\STTP60H.rnf
3.95 acres
Impervious
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
5.71 acres
Total Area 9.66 acres
Peak Discharge: 2.72 CFS at 6:00 on Jan 9 in 1990
Storing Time
Time Series Computed
KCRTS Command
Series File:c-230.tsf
Enter the Analysis TOOLS Module
Analysis Tools Command
B-20
SE 14.f' Street-June 2007
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-230.tsf
LogPearson III Coefficients
Time Series File:c-230.tsf
Project Location:Sea-Tac
Mean= 0.197 StdDev~ 0.103
Skew~ 0.461
Frequencies & Peaks saved to File:c-230.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-230.tsf
Compu~ing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-230.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Project Location : Sea-Tac
Computing Series c-232.tsf
Regional Scale Factor : 1.00
Data Type: Historic
Creating Hourly Time Series File
Till Forest
Loading Time Series File:C:\KC SWDM\KC DATA\STTF60H.rnf
1.38 acres
Total Area 1.38 acres
Peak Discharge: 0.093 CFS at 9:00 on Jan 9 in 1990
Storing Time Series File:c-232.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-232.tsf
LogPearson III Coefficients
Time Series File:c-232.tsf
Project Location:Sea-Tac
Mean~ -1.477 StdDev~ 0.232
Skew~ -0.124
SE 144'1' Street -June 2007
Frequencies & Peaks saved to File:c-232.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
B-21
Loading Time Series File:c-232.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-232.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Project Location : Sea-Tac
Computing Series c-240.tsf
Regional Scale Factor: 1.00
Data Type : Historic
Creating Hourly Time Series File
Loading Time Series File:C:\KC_SWDM\KC_DATA\STTG60H.rnf
Till Grass 3.65 acres
Impervious
Loading Time Series File:C:\KC_SWDM\KC_DATA\STEI60H.rnf
4.48 acres
Total Area 8.13 acres
Peak Discharge: 2.56 CFS at 6:00 on Jan 9 in 1990
Storing Time Series File:c-240.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-240.tsf
LogPearson III Coefficients
Time Series File:c-240.tsf
Project Location:Sea-Tac
Mean-0.137 StdDev-0.114
Skew-0.402
Frequencies & Peaks saved to File:c-240.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-240.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-240.dur
SE J 4,th Street June 2007
Analysis Tools Command
RETURN to Previous Menu
B-22
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Project Location : Sea-Tac
Computing Series c-241.tsf
Regional Scale Factor : 1.00
Data Type : Historic
Creating Hourly Time Series File
Loading Time Series File:C:\KC SWDM\KC DATA\STTF60H.rnf
Till Forest 0.23 acres
Till Grass
Impervious
Loading Time Series File:C:\KC SWDM\KC DATA\STTG60H.rnf
2.99 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
3.68 acres
Total Area 6.90 acres
Peak Discharge: 2.12 CFS at 6:00 on Jan 9 in 1990
Storing Time Series File:c-241.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-241.tsf
LogPearson III Coefficients
Time Series File:c-241.tsf
Project Location:Sea-Tac
Mean= 0.052 StdDev= 0.114
Skew= 0. 4 03
Frequencies & Peaks saved to File:c-241.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading T~me Series File:c-241.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-241.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Project Location : Sea-Tac
Computing Series : c-244.tsf
B-23
SE I 4,rn Street -June 2007
Regional Scale Factor: 1.00
Data Type : Historic
Creating Hourly Time Series File
Till Forest
Till Pasture
Till Grass
Impervious
Loading Time Series File:C:\KC SWDM\KC DATA\STTF60H.rnf
0.7lacres
Loading Time Series File:C:\KC SWDM\KC DATA\STTP60H.rnf
11.46 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STTG60H.rnf
10.75 acres
Loading Time Series File:C:\KC_SWDM\KC_DATA\STEI60H.rnf
4.68 acres
Total Area 27.60 acres
Peak Discharge: 5.19 CFS at 6:00 on Jan 9 in 1990
Storing Time
Time Series Computed
Series File:c-244.tsf
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-244.tsf
LogPearson III Coefficients
Time Series File:c-244.tsf
Project Location:Sea-Tac
Mean= 0.350 StdDev~ 0.151
Skew~ 0.463
Frequencies & Peaks saved to File:c-244.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-244.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-244.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Project Location : Sea-Tac
Computing Series c-250.tsf
Regional Scale Factor : 1.00
Data Type : Historic
Creating Hourly Time Series File
Loading Time Series File:C:\KC SWDM\KC DATA\STTP60H.rnf
Till Pasture 0.17 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STTG60H.rnf
B-24
SE J 4,f" Street-June 2007
Till Grass
Impervious
4.66 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
3.23 acres
Total Area 8.06 acres
Peak Discharge: 2.27 CFS at 6:00 on Jan 9 in 1990
Storing Time Series File:c-250.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-250.tsf
LogPearson III Coefficients
Time Series File:c-250.tsf
Project Location:Sea-Tac
Mean= 0.048 StdDev~ 0.126
Skew~ 0.396
Frequencies & Peaks saved to File:c-250.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-250.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-250.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production
Sea-Tac
c-260.tsf
1. 00
of Runoff Time Series
Project Location:
Comput.:._ng Series
Regional Scale Factor:
Data Type : Historic
Creating Hourly Time Series File
Loading Time Series File:C:\KC SWDM\KC DATA\STTG60H.rnf
Till Grass 2.33 acres
Impervious
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
1.74 acres
Total Area 4.07
Peak Discharge: 1.18 CFS at
SE 14.f' Street -June 2007
acres
6:00 on Jan 9 in 1990
Storing Time
Time Series Computed
KCRTS Command
B-25
Series File:c-260.tsf
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-260.tsf
LogPearson III Coefficients
Time Series File:c-260.tsf
Project Location:Sea-Tac
Mean~ -0.230 StdDev~ 0.124
Skew~ 0.395
Frequencies & Peaks saved to File:c-260.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-260.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-260.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
of Runoff Time Series
Project Location :
Production
Sea-Tac
c-270. tsf
1. 00
Computing Series
Regional Scale Factor:
Data Type : Historic
Creating Hourly Time Series File
Till Grass
Impervious
Loading Time Series File:C:\KC_SWDM\KC_DATA\STTG60H.rnf
2.22 acres
Loading Time Series File:C:\KC_SWDM\KC_DATA\STEI60H.rnf
1.60 acres
Total Area 3.82 acres
Peak Discharge: 1.10 CFS at 6:00 on Jan 9 in 1990
Storing Time
Time Series Computed
Series File:c-270.tsf
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Cormnand
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-270.tsf
LogPearson III Coefficients
8-26
SE !44'n Street-June 2007
Time Series File:c-270.tsf
Project Location:Sea-Tac
Mean~ -0.263 StdDev~ 0.125
Skew~ 0. 392
Frequencies & Peaks saved to File:c-270.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-270.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-270.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Project Location : Sea-Tac
Computing Series c-300.tsf
Regional Scale Factor: 1.00
Data Type : Historic
Creating Hourly Time Series File
Loading Time Series File:C:\KC SWDM\KC DATA\STTF60H.rnf
Till Forest 9.47 acres
Till Pasture
Till Grass
Impervious
Loading Time Series File:C:\KC SWDM\KC DATA\STTP60H.rnf
1.73 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STTG60H.rnf
4.13 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
1.56 acres
Total Area 16.89 acres
Peak Discharge: 2.19 CFS at 6:00 on Jan 9 in 1990
Storing T~me
Time Series Computed
Series File:c-300.tsf
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-300.tsf
LogPearson III Coefficients
Time Series File:c-300.tsf
Project Location:Sea-Tac
SE 14¢11 Street -June 2007
Mean~ -0.057 StdDev~ 0.172
Skew~ 0.335
Frequencies & Peaks saved to File:c-300.pks
Analysis Tools Command
B-27
Compute Flow DURATION and Exceedence
Loading Time Series File:c-300.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-300.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
of Runoff Time Series
Project Location :
Production
Sea-Tac
c-304.tsf
1. 00
Computing Series
Regional Scale Factor:
Data Type : Historic
Creating Hourly Time Series File
Till Forest
Till Pasture
Till Grass
Impervious
Loading Time Series File:C:\KC SWDM\KC DATA\STTF60H.rnf
2 .12 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STTP60H.rnf
1.36 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STTG60H.rnf
5.73 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
3.74 acres
Total Area 12.95 acres
Peak Discharge: 2.93 CFS at 6:00 on Jan 9 in 1990
Storing Time Series File:c-304.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-304.tsf
LogPearson III Coefficients
Time Series File:c-304.tsf
Project Location:Sea-Tac
Mean= 0.141 StdDev~ 0.132
Skew~ 0.426
Frequencies & Peaks saved to File:c-304.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Computing Interval Locations
Computing Flow Durations
SE J 4,(n Street-June 2007
Loading Time Series File:c-304.tsf
B-28
Durations & Exceedence Probabilities to File;c-304.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Project Location : Sea-Tac
Comput~ng Series c-306.tsf
Regional Scale Factor : 1.00
Data Type : Historic
Creating Hourly Time Series File
Loading Time Series File:C:\KC SWDM\KC DATA\STTF60H.rnf
Till Forest 1.25 acres
Till Pasture
Till Grass
Impervious
Loading Time Series File:C:\KC SWDM\KC DATA\STTP60H.rnf
0.15 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STTG60H.rnf
0.28 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
0.08 acres
Total Area 1.76 acres
Peak Discharge: 0.177 CFS at 6:00 on Jan 9 in 1990
Storing Time
Time Series Computed
Series File:c-306.tsf
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-306.tsf
LogPearson III Coefficients
Time Series File:c-306.tsf
Project Location:Sea-Tac
Mean--1.180 StdDev-0.204
Skew-0.041
Frequencies & Peaks saved to File:c-306.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-306.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-306.dur
SE 14.f' Street-June 2007
Analysis Tools Command
RETURN to Previous Menu
B-29
KCRTS Corrunand
CREATE a new Time Series
Project Location :
Production of Runoff Time Series
Sea-Tac
Computing Series
Regional Scale Factor:
c-310.tsf
1. 00
Data Type : Historic
Creating Hourly Time Series File
Till Forest
Loading Time Series File:C:\KC SWDM\KC DATA\STTF60H.rnf
9.32 acres
Total Area 9.32 acres
Peak Discharge: 0.627 CFS at 9:00 on Jan 9 in 1990
Storing Time Series File:c-310.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-310.tsf
LogPearson III Coefficients
Time Series File:c-310.tsf
Project Location:Sea-Tac
Mean~ -0.648 StdDev~ 0.233
Skew~ -0.139
Frequencies & Peaks saved to File:c-310.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-310.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-310.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Project Location: Sea-Tac
Computing Series c-320.tsf
Regional Scale Factor: 1.00
Data Type : Historic
Creating Hourly Time Series File
Loading Time Series File:C:\KC SWDM\KC DATA\STTF60H.rnf
B-30
SE J4,fh Street-June 2007
Till Forest
Till Pasture
Till Grass
Impervious
8.92 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STTP60H.rnf
0.18 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STTG60H.rnf
0. 33 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
0.09 acres
Total Area 9.52 acres
Peak Discharge: 0.693 CFS at 9:00 on Jan 9 in 1990
Storing Time Series File:c-320.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-320.tsf
LogPearson III Coefficients
Time Series File:c-320.tsf
Project Location:Sea-Tac
Mean--0.597 StdDev-0.226
Skew--0.141
Frequencies & Peaks saved to File:c-320.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-320.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-320.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Project Location : Sea-Tac
Computing Series c-330.tsf
Regional Scale Factor : 1.00
Data Type : Historic
Creating Hourly Time Series File
Loading Time Series File:C:\KC SWDM\KC DATA\STTF60H.rnf
Till Forest 1.37 acres
Till Pasture
Till Grass
SE J 4,f' Street--June 2007
Loading Time Series File:C:\KC_SWDM\KC_DATA\STTP60H.rnf
0.34 acres
Loading Time Series File:C:\KC_SWDM\KC_DATA\STTG60H.rnf
0. 62 acres
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60H.rnf
B-31
Impervious 0.17 acres
Total Area 2.50 acres
Peak Discharge: 0.307 CFS at 6:00 on Jan 9 in 1990
Storing Time Series File:c-330.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Flow Frequency Analysis
Loading Stage/Discharge curve:c-330.tsf
LogPearson III Coefficients
Time Series File:c-330.tsf
Project Location:Sea-Tac
Mean= -0.930 StdDev= 0.187
Skew= 0.198
Frequencies & Peaks saved to File:c-330.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:c-330.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:c-330.dur
SE 144'h Street-June 2007
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
eXit KCRTS Program
B-32
Appendix B.2 KCRTS Pond Designs
Hamilton Place -Retention/Detention Facility
Type of Facility:
Side Slope:
Pond Bottom Length:
Pond Bottom Width:
Pond Bottom Area:
Top Area at 1 ft. FB:
Effective Storage Depth:
Stage 0 Elevation:
Storage Volume:
Riser Head:
Riser
Number
Orifice#
1
2
of
Diameter:
orifices:
Height
(ft)
0.00
2.90
Detention Pond
3.00 H: lV
145.91 ft
71.63 ft
10452. sq. ft
19580. sq. ft
0.449 acres
5.00 ft
505.00 ft
70076. cu. ft
1. 609 ac-ft
5.00
12.00
2
Diameter
(in)
1. 2 6
1. 7 0
ft
inches
Full Head
Discharge
(CFS)
0 .096
0 .114
Top Notch Weir: None
Outflow Rating Curve: None
Evendell Plat -Retention/Detention Facility
Type of Facility:
Side Slope:
Pond Bottom Length:
Pond Bottom Width:
Pond Bottom Area:
Top Area at 1 ft. FB:
Effective Storage Depth:
Stage O Elevation:
Storage Volume:
Riser Head:
Riser Diameter:
Number of orifices:
Orifice # Height
(ft)
1 0.00
2 5.50
3 5. 90
Detention Pond
3.00 H:lV
167.00 ft
58.00 ft
9686. sq. ft
23762. sq. ft
0. 54 6
7.50
452.00
115676.
2. 656
7.50
18.00
3
acres
ft
ft
cu. ft
ac-ft
ft
inches
Diameter
(in)
Full Head
Discharge
1. 50
2.30
2.80
(CFS)
0.167
0.203
0.269
Top Notch Weir: None
Outflow Rating Curve: None
Liberty Grove -Retention/Detention Facility
Type of Facility:
Side Slope:
Pond Bottom Length:
Pond Bottom Width:
SE z 44n Srreet -June 2007
Detention Pond
2.00 H:lV
178. 12 ft
89.06 ft
B-33
Pipe
Diameter
(in)
4. 0
Pipe
Diameter
(in)
6.0
6. 0
Pond Bottom Area:
Top Area at 1 ft. FB:
Effective Storage Depth:
Stage O Elevation:
Storage Volume:
Riser Head:
Riser Diameter:
Number of orifices:
Orifice#
1
2
3
Height
(ft)
0.00
3.65
4.81
15863.
24128.
0.554
6. 00
456.00
115567.
2.653
6. 00
18. 00
3
sq. ft
sq. ft
acres
ft
ft
cu. ft
ac-ft
ft
inches
Diameter
(in)
3.31
4.39
7.69
Full Head
Discharge
(CFS)
0. 728
0.801
1. 749
Top Notch Weir: None
Outflow Rating Curve: None
Nichol's Place -Retention/Detention Facility
Type of Facility:
Side Slope:
Pond Bottom Length:
Pond Bottom Width:
Pond Bottom Area:
Top Area at 1 ft. FB:
Effective Storage Depth:
Stage O Elevation:
S::orage Volume:
Riser Head:
Riser Diameter:
Number of orifices:
Orifice # Height
(ft)
1 0.00
2 3.90
Top Notch Weir:
Length:
Weir Height:
Outflow Rating Curve:
SE 14.fn Street-June 2007
Detention Pond
0.00 H:lV
82.00 ft
71. 00 ft
5822. sq. ft
5822. sq. ft
0.134 acres
5. 00 ft
447.00 ft
29110. cu. ft
0.668 ac-ft
5.00 ft
18.00 inches
2
Full Head
Diameter Discharge
(in) (CFS)
0.87 0.046
1. 71 0.083
Rectangular
1. 00 in
4.50 ft
None
B-34
Pipe
Diameter
(in)
8.0
10.0
Pipe
Diameter
(in)
4.0
Appendix 8.3 KCRTS Peak Flow Rates
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-10.tsf Mean= -1.641 StdDev~ 0.141
Project Location:Sea-Tac Skew~ 1.196
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0.022 26 2/16/49 21:00 0.070 1 8 9. 50 0.989
0.070 1 3/03/50 16: 00 0.046 2 32.13 0.969
0.034 6 2/09/51 2:00 0. 044 3 19.58 0.949
0.018 37 10/15/51 13: 00 0.039 4 14.08 0. 92 9
0.017 44 3/24 I 53 15:00 0.036 5 10.99 0.909
0.022 27 12/19/53 19: 00 0.034 6 9.01 0.889
0.023 21 2/07/55 17:00 0.033 7 7.64 0.869
0.025 15 12/20/55 17:00 0.031 8 6.63 0.849
0. 022 22 12/09/56 14:00 0.031 9 5. 8 6 0.829
0.021 28 12/25/57 16: DO 0.030 10 5.24 0.809
0. 021 29 1/26/59 20:00 0.028 11 4.75 0.789
0.025 17 2/06/60 17:00 0.028 12 4.34 0. 7 69
0. 02 6 13 2/14/61 21: 00 0.026 13 3.99 0.749
0.018 38 11/22/61 2:00 0.025 14 3.70 0.729
0.019 34 12/15/62 2: 00 0.025 15 3.44 0.709
0. 022 23 12/31/63 23:00 0.025 16 3.22 0.690
0.018 39 12/21/64 4: 00 0.025 17 3.03 0.670
0.018 40 1/05/66 16:00 0.024 18 2.85 0.650
0.028 12 1/19/67 14: 00 0.024 19 2.70 0.630
0.030 10 8/24/68 16:00 0.023 20 2.56 0.610
0.016 46 12/03/68 16:00 0.023 21 2.44 0.590
0.018 41 1/13/70 22:00 0.022 22 2.32 0.570
0.018 42 12/05/70 9:00 0.022 23 2 .22 0.550
0.044 3 2/27 /72 7:00 0. 022 24 2.13 0.530
0. 017 45 1/13/73 2:00 0.022 25 2.04 0.510
0.018 35 11/28/73 9:00 0.022 26 1. 96 0. 4 90
0.023 20 12/26/74 23:00 0.022 27 1. 89 0.470
0.016 47 1/14/76 6:00 0 .021 28 1. 82 0. 4 50
0.020 30 8/26/77 2:00 0.021 29 1. 7 5 0.430
0.028 11 9/17/78 2:00 0.020 30 1. 70 0.410
0.025 14 9/08/79 15:00 0.020 31 1. 64 0.390
0.022 25 12/14/79 21:00 0.019 32 1. 59 0.370
0.024 18 11/21/80 11: 00 0.019 33 1. 54 0.350
0.033 7 10/06/81 0:00 0.019 34 1. 4 9 0.330
0.025 16 10/28/82 16:00 0.018 35 1. 45 0.310
0.020 31 3/15/84 20:00 0.018 36 1. 41 0. 291
0.017 43 6/06/85 22:00 0.018 37 1. 37 0.271
0.022 24 1/18/86 16: 00 0.018 38 1. 33 0.251
0.031 9 10/26/86 0:00 0.018 39 1. 30 0.231
0.015 49 11/11/87 0:00 0.018 40 1. 27 0.211
0.019 32 8/21/89 17:00 0.018 41 1. 24 0. 191
0. 04 6 2 1/09/90 8:00 0.018 42 1. 21 0 .171
0.036 5 11/24/90 8:00 0.017 43 1.18 0.151
0.018 36 1/27 /92 15:00 0.017 44 1.15 0.131
0.013 50 11/01/92 16:00 0.017 45 1.12 0 .111
0.015 48 11/30/93 22:00 0.016 46 1.10 0.091
0.019 33 11/30/94 4:00 0.016 47 1. 08 0. 071
0.039 4 2/08/96 10:00 0.015 48 1. 05 0.051
0.031 8 1/02/97 6:00 0.015 49 1. 03 0.031
0.024 19 10/04/97 15:00 0. 013 50 1. 01 0. 011
B-35
SE 144°' Street June 2007
Co:nputed Peaks 0.063 100.00 0.990
Computed Peaks 0.053 50.00 0.980
Computed Peaks 0.045 25.00 0. 960
Computed Peaks 0.035 10.00 0.900
Computed Peaks 0.034 8.00 0.875
Computed Peaks 0.029 5.00 0.800
Computed Peaks 0. 021 2.00 0.500
Computed Peaks 0.018 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-20.tsf Mean= -0.857 StdDev~ 0 .119
Project Location:Sea-Tac Skew~ 0. 941
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0.135 24 2/16/49 21 :00 0.331 1 8 9. 50 0.989
0.331 1 3/03/50 16:00 0.258 2 32.13 0. 969
0 .173 10 2/09/51 2:00 0.222 3 19.58 0. 94 9
0 .115 37 10/15/51 13:00 0.218 4 14.08 0. 92 9
0. 106 44 3/24/53 15:00 0.210 5 10. 99 0.909
0.132 27 12/19/53 19:00 0 .197 6 9.01 0.889
0.133 26 2/07/55 17:00 0.195 7 7. 64 0.869
0.139 22 12/20/55 17:00 0.191 8 6.63 0.849
0.143 18 12/09/56 14:00 0.178 9 5.86 0.829
0.132 28 12/25/57 16:00 0.173 10 5.24 0.809
0 .116 34 1/26/59 20:00 0.170 11 4.75 0.789
0.135 23 2/06/60 17:00 0.170 12 4.34 0.769
0.140 21 2/14/61 21:00 0 .160 13 3.99 0.749
0 .114 38 11/22/61 2:00 0.158 14 3.70 0. 729
0 .114 39 12/15/62 2:00 0.155 15 3.44 0.709
0.135 25 12/31/63 23:00 0.150 16 3.22 0.690
0 .115 36 12/21/64 4:00 0.149 17 3.03 0.670
0 .114 40 1/05/66 16:00 0.143 18 2.85 0.650
0.170 11 11/13/66 19:00 0.140 19 2. 70 0.630
0 .191 8 8/24/68 16: 00 0.140 20 2.56 0.610
0.103 46 12/03/68 16: 00 0.140 21 2. 44 0.590
0 .113 41 1/13/70 22:00 0.139 22 2.32 0.570
0 .111 42 12/05/70 9:00 0.135 23 2.22 0.550
0.222 3 2/27/72 7:00 0.135 24 2.13 0.530
0.104 45 1/13/73 2:00 0.135 25 2.04 0.510
0 .116 35 11/28/73 9:00 0.133 26 1. 96 0. 4 90
0.149 17 12/26/74 23:00 0.132 27 1. 89 0.470
0.102 47 11/13/75 19:00 0.132 28 1. 82 0.450
0.129 29 8/26/77 2:00 0.129 29 1. 75 0.430
0.178 9 9/17/78 2:00 0.123 30 1. 70 0.410
0.160 13 9/08/79 15:00 0.122 31 1. 64 0.390
0 .140 19 12/14/79 21: 00 0.121 32 1.59 0.370
0.155 15 11/21/80 11: 00 0 .117 33 1. 54 0.350
0.210 5 10/06/81 0:00 0 .116 34 1. 4 9 0.330
0.158 14 10/28/82 16:00 0 .116 35 1.45 0.310
0.123 30 3/15/84 20:00 0 .115 36 1. 41 0.291
0.110 43 6/06/85 22:00 0 .115 37 1. 37 0.271
0.140 20 1/18/86 16:00 0 .114 38 1. 33 0.251
0 .197 6 10/26/86 0:00 0.114 39 1. 30 0.231
0.094 49 11/11/87 0:00 0.114 40 1. 27 0. 211
0.122 31 8/21/89 17:00 0.113 41 1. 24 0 .191
0.258 2 1/09/90 6:00 0.111 42 1.21 0. 171
0.218 4 11/24/90 8:00 0 .110 43 1.18 0.151
0 .117 33 1/27/92 15:00 0.106 44 1.15 o. 131
B-36
SE I 4.fn Street-June 2007
0.086 50 11/01/92 16: 00 0.104 45 1.12 0 .111
0.097 48 11/30/93 22:00 0.103 46 1.10 0.091
0.121 32 11/30/94 4:00 0.102 47 1. 08 0. 071
0.195 7 2/08/96 10: 00 0.097 48 1. 05 0.051
0.170 12 1/02/97 6:00 0.094 49 1. 03 0.031
0.150 16 10/04/97 15:00 0.086 50 1. 01 0. 011
Computed Peaks 0.315 100.00 0.990
Computed Peaks 0 .277 50.00 0.980
Computed Peaks 0.242 25.00 0.960
Computed Peaks 0.201 10.00 0.900
Computed Peaks 0.193 8.00 0.875
Computed Peaks 0 .171 5.00 0.800
Computed Peaks 0.133 2.00 0.500
Computed Peaks 0 .112 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-30.tsf Mean= -0.949 StdDev-0.121
Project Location:Sea-Tac Skew= 0. 973
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0.109 25 2/16/49 21:00 0. 276 1 89.50 0.989
0. 27 6 1 3/03/50 16:00 0.210 2 32.13 0. 969
0.143 9 2/09/51 2:00 0.183 3 19.58 0. 94 9
0. 092 37 10/15/51 13:00 0.176 4 14.08 0. 92 9
0.086 44 3/24/53 15:00 0.169 5 10.99 0. 909
0.106 27 12/19/53 19: 00 0 .161 6 9.01 0.889
0.108 26 2/07/55 17:00 0.158 7 7.64 0.869
0 .114 20 12/20/55 17:00 0.154 8 6.63 0.849
0 .116 18 12/09/56 14:00 0.143 9 5.86 0.829
0.106 28 12/25/57 16: 00 0.143 10 5.24 0.809
0.095 33 1/26/59 20:00 0.139 11 4. 7 5 0.789
0 .110 23 2/06/60 17:00 0.137 12 4. 34 0.769
0 .114 19 2/14/61 21:00 0.129 13 3.99 0.749
0. 0 92 38 11/22/61 2:00 0 .127 14 3.70 0.729
0. 092 39 12/15/62 2:00 0.124 15 3.44 0.709
0.109 24 12/31/63 23:00 0.121 16 3.22 0.690
0. 093 36 12/21/64 4:00 0.120 17 3.03 0. 670
0. 091 40 1/05/66 16:00 0 .116 18 2. 85 0.650
0.137 12 11/13/66 19:00 0 .114 19 2.70 0.630
0.154 8 8/24/68 16:00 0 .114 20 2.56 0.610
0.083 46 12/03/68 16:00 0 .113 21 2.44 0. 590
0. 091 41 1/13/70 22:00 0 .113 22 2.32 0.570
0.089 42 12/05/70 9:00 0 .110 23 2.22 0.550
0.183 3 2/27 /72 7:00 0.109 24 2.13 0.530
0.084 45 1/13/73 2:00 0.109 25 2.04 0.510
0.093 35 11/28/73 9:00 0.108 26 1. 96 0.490
0.120 17 12/26/74 23:00 0.106 27 1. 89 0.470
0.082 47 11/13/75 19:00 0.106 28 1. 82 0.450
0.104 29 8/26/77 2:00 0.104 29 1. 75 0.430
0.143 10 9/17 /78 2:00 0.099 30 1. 70 0.410
0.129 13 9/08/79 15:00 0.098 31 1. 64 0.390
0 .113 21 12/14/79 21: 00 0.097 32 1. 59 0.370
0.124 15 11/21/80 11: 00 0.095 33 1. 54 0.350
0.169 5 10/06/81 0:00 0. 094 34 1. 4 9 0.330
0.127 14 10/28/82 16: 00 0.093 35 1. 45 0.310
0.099 30 3/15/84 20:00 0.093 36 1. 41 0.291
0.088 43 6/06/85 22: 00 0. 092 37 1.37 0.271
0 .113 22 1/18/86 16: 00 0. 092 38 1. 33 0.251
B-37
SE 144'~ Street June 2007
0.158 7 10/26/86 0: 00 0.092 39 1. 30 0.231
0. 07 6 49 11/11/87 0:00 0. 0 91 40 1.27 0. 211
0.098 31 8/21/89 17: 00 0.091 41 1.24 0.191
0.210 2 1/09/90 6:00 0.089 42 1. 21 0 .171
0.176 4 11/24/90 8: 00 0.088 43 1.18 0.151
0. 0 94 34 1/27/92 15:00 0.086 44 1.15 0.131
0.069 50 11/01/92 16:00 0.084 45 1.12 0 .111
0.078 48 11/30/93 22:00 0.083 46 1.10 0.091
0.097 32 11/30/94 4:00 0.082 47 1. 08 0.071
0.161 6 2/08/96 10:00 0.078 48 1. 05 0.051
0.139 11 1/02/97 6:00 0. 07 6 49 1. 03 0.031
0.121 16 10/04/97 15:00 0.069 50 1. 01 0. 011
Computed Peaks 0.259 100.00 0.990
Computed Peaks 0.227 50.00 0.980
Computed Peaks 0 .198 25.00 0. 960
Computed Peaks 0 .163 10.00 0.900
Computed Peaks 0.157 8.00 0.875
Computed Peaks 0 .139 5.00 0.800
Computed Peaks 0.107 2.00 0.500
Computed Peaks 0.090 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-40.tsf Mean= -1.104 StdDev~ 0.105
Project Location:Sea-Tac Skew= 0.664
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0.078 21 2/16/49 21:0C 0.145 1 89.50 0.989
0.145 1 3/03/50 16:0C 0.135 2 32.13 0.969
0.085 17 2/09/51 2:00 0.124 3 19.58 0.949
0.068 35 10/15/51 13:00 0.121 4 14.08 0.929
0. 0 62 43 3/24/53 15:00 0 .116 5 10.99 0.909
0.074 27 12/19/53 19:00 0 .112 6 9.01 0.889
0 .077 23 11/25/ 54 2:00 0.107 7 7.64 0.869
0.075 26 11/18/55 15:00 0.105 8 6.63 0.849
0.084 18 12/C9/56 14:00 0.100 9 5.86 0.829
0.077 22 12/25/57 16:00 0.094 10 5.24 0.809
0.061 44 1/26/59 20:00 0.094 11 4.75 0.789
0. 072 28 11/20/59 5:00 0.093 12 4.34 0.769
0.072 29 2/14/61 21:00 0. 091 13 3.99 0.749
0. 067 37 11/22/61 2:00 0.089 14 3.70 0.729
0.065 40 12/15/62 2:00 0.088 15 3.44 0.709
0.076 24 12/31/63 23:00 0.088 16 3.22 0.690
0.067 36 12/21/64 4:00 0.085 17 3. 03 0.670
0.066 39 1/05/66 16:00 0.084 18 2.85 0.650
0.100 9 11/13/66 19:00 0.083 19 2.70 0.630
0 .112 6 8/24/68 16:00 0.080 20 2.56 0.610
0.060 45 12/03/68 16:00 0.078 21 2.44 0.590
0.067 38 1/13/70 22:00 0. 077 22 2.32 0.570
0.065 41 12/05/70 9:00 0.077 23 2.22 0.550
0.107 7 2/27 /72 7:00 0. 07 6 24 2.13 0.530
0.060 46 1/13/73 2: 00 0. 07 6 25 2. 04 0.510
0.068 34 11/28/73 9:00 0. 075 26 1. 96 0.490
0.088 15 12/26/74 23:00 0.074 27 1. 8 9 0.470
0.060 47 11/13/75 19: 00 0 .072 28 1. 82 0.450
0.076 25 8/26/77 2:00 0 .072 29 1. 75 0.430
0.105 8 9/17/78 2:00 0 .072 30 1. 70 0.410
0. 0 94 10 9/08/79 15:00 0 .071 31 1. 64 0.390
0.083 19 12/14/79 21: 00 0.070 32 1. 59 0.370
B-38
SE I 44'n Street-June 2007
0.091 13 11/21/80 11: 00 0.069 33 1. 54 0.350
0.124 3 10/06/81 0:00 0.068 34 1. 49 0.330
0.093 12 10/28/82 16:00 0.068 35 1. 45 0.310
0.070 32 1/03/84 1:00 0.067 36 1. 41 0. 2 91
0.064 42 6/06/85 22:00 0.067 37 1. 37 0.271
0.080 20 1/18/86 16: 00 0.067 38 1. 33 0.251
0 .116 5 10/26/86 0:00 0.066 39 1. 30 0.231
0.055 49 11/11/87 0:00 0.065 40 1.27 0. 211
0.072 30 8/21/89 17:00 0.065 41 1. 24 0.191
0 .135 2 1/09/90 6:00 0.064 42 1. 21 0 .171
0.121 4 11/24/90 8:00 0.062 43 1.18 0.151
0.069 33 1/27/92 15:00 0.061 44 1.15 0.131
0.050 50 11/01/92 16:00 0.060 45 1.12 0 .111
0.057 48 9/03/94 10:00 0.060 46 1.10 0.091
0.071 31 11/30/94 4:00 0.060 47 1. 08 0.071
0.094 11 2/08/96 10:00 0.057 48 1. 05 0.051
0.088 16 1/02/97 6:00 0.055 49 1. 03 0.031
0.089 14 10/04/97 15:00 0.050 50 1. 01 0. 011
Computed Peaks 0.154 100.00 0.990
Computed Peaks 0 .140 50.00 0.980
Computed Peaks 0.126 25.00 0. 960
Computed Peaks 0.108 10.00 0.900
Computed Peaks 0.105 8.00 0.875
Computed Peaks 0.095 5.00 0.800
Computed Peaks 0.077 2.00 0.500
Computed Peaks 0.065 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-42.tsf Mean= -0.747 StdDev= 0 .110
Project Location:Sea-Tac Skew= 0. 7 94
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0 .175 21 2/16/49 21:00 0. 372 1 89.50 0.989
0.372 1 3/03/50 16:00 0. 319 2 32.13 0. 969
0.207 14 2/09/51 2:00 0.277 3 19.58 0. 94 9
0.151 36 10/15/51 13:00 0. 27 6 4 14.08 0. 92 9
0.139 44 3/24/53 15:00 0. 2 63 5 10.99 0. 909
0.169 28 12/19/53 19: 00 0.259 6 9.01 0. 88 9
0 .172 25 11/25/54 2:00 0.251 7 7.64 0.869
0 .172 23 12/20/55 17:00 0.234 8 6.63 0.849
0.188 18 12/09/56 14:00 0.230 9 5.86 0.829
0 .172 24 12/25/57 16:00 0.224 10 5.24 0.809
0.144 43 1/26/59 20:00 0.210 11 4.75 0.789
0 .167 29 2/06/60 17:00 0.209 12 4.34 0.769
0.171 26 2/14/61 21:00 0.208 13 3. 99 0.749
0.149 37 11/22/61 2:00 0.207 14 3.70 0. 729
0.147 40 12/15/62 2:00 0.203 15 3.44 0.709
0.174 22 12/31/63 23:00 0 .197 16 3.22 0.690
0.151 35 12/21/64 4:00 0 .196 17 3.03 0.670
0 .149 38 1/05/66 16: 00 0.188 18 2.85 0.650
0.224 10 11/13/66 19:00 0.185 19 2.70 0.630
0.251 7 8/24/68 16: 00 0.182 20 2.56 0.610
0.135 46 12/03/68 16:00 0.175 21 2.44 0.590
0.148 39 1/13/70 22:00 0.174 22 2.32 0.570
0.146 41 12/05/70 9:00 0.172 23 2.22 0.550
0. 2 63 5 2/27/72 7:00 0.172 24 2.13 0.530
0.136 45 1/13/73 2:00 0 .172 25 2. 04 0.510
0.153 34 11/28/73 9:00 0 .171 26 1.96 0. 4 90
B-39
SE 14,tn Street-June 2007
D .196 17 12/26/74 23:00 0 .170 27 1. 8 9 0.470
D .134 47 11/13/75 19: 00 0.169 28 1. 82 0.450
0.170 27 8/26/77 2:00 0.167 29 1. 75 0.430
0.234 8 9/17/78 2:00 0.160 30 1. 70 0. 410
0.210 11 9/08/79 15:00 0.158 31 1.64 0.390
0.185 19 12/14/79 21:00 0.158 32 1. 59 0.370
0.203 15 11/21/80 11: 00 0.154 33 1.54 0.350
0.276 4 10/06/81 0:00 0.153 34 1. 4 9 0.330
0.208 13 10/28/82 16:00 0.151 35 1.45 0.310
0.158 32 1/03/84 1: OD 0.151 36 1. 41 0.291
0.144 42 6/06/85 22:00 0.149 37 1. 37 0.271
0.182 20 1/18/86 16:00 0.149 38 1. 33 0.251
0.259 6 10/26/86 0:00 0.148 39 1. 30 0.231
0.124 49 11/11/87 0: DO 0.147 40 1.27 0. 211
0.160 30 8/21/89 17:00 0.146 41 1. 24 0.191
0.319 2 1/09/90 6: 00 0.144 42 1.21 0 .171
0.277 3 11/24/90 8:00 0.144 43 1.18 0.151
0.154 33 1/27/92 15:00 0.139 44 1. 15 0.131
0 .113 50 11/01/92 16:00 0.136 45 1.12 0 .111
0.128 48 11/30/93 22:00 0.135 46 1. 10 0.091
0.158 31 11/30/94 4:00 0.134 47 1. 08 0.071
0.230 9 2/08/96 10:00 0.128 48 1. 05 0.051
0.209 12 1/02/97 6:00 0.124 49 1. 03 0.031
0.197 16 10/04/97 15:00 0.113 50 1. 01 0. 011
Computed Peaks 0.373 100.00 0.990
Computed Peaks 0.334 SO.DO 0.980
Computed Peaks 0. 2 97 25.00 0. 960
Computed Peaks 0.251 10.00 0.900
Computed Peaks 0.243 8.00 0.875
Computed Peaks 0. 218 5.00 0.800
Computed Peaks 0.173 2.00 0.500
Computed Peaks 0.147 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-44.tsf Mean= -0. 596 StdDev~ 0. 096
Project Location:Sea-Tac Skew= 0.562
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0.253 21 2/16/49 21: 00 0.407 1 89.50 0. 98 9
0.368 6 3/03/50 16: 00 0.407 2 32 .13 0. 969
0.246 25 2/09/51 2:00 0.382 3 19.58 0.949
0.223 34 10/15/51 13:00 0.382 4 14. 08 0. 929
0.203 43 3/24/53 15:00 0.370 5 10.99 0.909
0.239 28 12/19/53 19:00 0.368 6 9. 01 0.889
0.253 22 11/25/54 2:00 0.345 7 7. 64 0.869
0.247 24 11/18/55 15:00 0.330 8 6.63 0.849
0.278 15 12/09/56 14: 00 0.310 9 5.86 0.829
0.254 20 12/25/57 16:00 0.307 10 5.24 0.809
0.194 47 11/03/58 17:00 0.303 11 4.75 0.789
0.239 27 11/20/59 5:00 0.300 12 4.34 0.769
0.214 40 2/14/61 21:00 0. 2 92 13 3.99 0. 74 9
0.221 36 11/22/61 2:00 0.289 14 3.70 0. 729
0.211 42 12/15/62 2:00 0 .278 15 3.44 0.709
0.244 26 12/31/63 23:00 0 .273 16 3.22 0.690
0.221 35 12/21/64 4:00 0.268 17 3.03 0.670
0. 219 38 1/05/66 16:00 0. 2 62 18 2.85 0.650
0.330 8 11/13/66 19:00 0. 2 60 19 2.70 0.630
0.370 5 8/24/68 16:00 0.254 20 2.56 0. 610
B-40
SE 144'h Street-June 2007
0.198 44 12/03/68 16: 00 0.253 21 2.44 0.590
0.220 37 1/13/70 22: 00 0.253 22 2.32 0.570
0.215 39 12/05/70 9:00 0.251 23 2.22 0.550
0.303 11 12/08/71 18:00 0.247 24 2.13 0.530
0.197 46 1/13/73 2:00 0. 24 6 25 2.04 0.51G
0. 22 6 33 11/28/73 9:00 0.244 26 1. 96 0.490
0.289 14 12/26/74 23:00 0.239 27 1. 89 0.470
0.198 45 11/13/7 5 19:00 0.239 28 1. 82 0.450
0.251 23 8/26/77 2:00 0.237 29 1. 75 0.430
0.345 7 9/17 /78 2:00 0.234 30 1. 70 0.410
0.310 9 9/08/79 15:00 0.231 31 1. 64 0.390
0. 273 16 12/14/79 21:00 0.228 32 1. 59 0.370
0.300 12 11/21/80 11: 00 0. 22 6 33 1. 54 0.350
0.407 1 10/06/81 0:00 0.223 34 1. 49 0.330
0.307 10 10/28/82 16: 00 0.221 35 1. 45 0.310
0.231 31 1/03/84 1:00 0.221 36 1. 41 0. 2 91
0.213 41 6/06/85 22:00 0.220 37 1. 37 0.271
0.262 18 1/18/86 16: 00 0.219 38 1. 33 0.251
0.382 3 10/26/86 0:00 0.215 39 1. 30 0.231
0.183 49 11/11/87 0:00 0.214 40 1. 27 o .211
0.237 29 8/21/89 17:00 0.213 41 1. 24 0.191
0.407 2 1/09/90 6:00 0.211 42 1.21 0.171
0.382 4 11/24/90 8:00 0.203 43 1.18 0. 151
0.228 32 1/27/92 15:00 0.198 44 1.15 0.131
0.166 50 11/01/92 16: 00 0 .198 45 1.12 0 .111
0.189 48 11/30/93 22:00 0.197 46 1.10 0. 0 91
0.234 30 11/30/94 4:00 0 .194 47 1. 08 0. 071
0.268 17 2/08/96 10:00 0.189 48 1. 05 0.051
0.260 19 1/02/97 6:00 0.183 49 1. 03 0.031
0. 292 13 10/04/97 15:00 0.166 50 1. 01 0. 011
Computed Peaks 0. 4 62 100.00 0.990
Computed Peaks 0.425 50.00 0.980
Computed Peaks 0.388 25.00 o. 960
Computed Peaks 0. 340 10.00 0.900
Computed Peaks 0.330 8.00 0.875
Computed Peaks 0. 303 5.00 0.800
Computed Peaks 0. 24 9 2. 00 0.500
Computed Peaks 0. 214 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-50.tsf Mean= -0.884 StdDev-0.095
Project Location:Sea-Tac Skew= 0.562
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0.130 21 2/16/49 21:00 0.210 1 89.50 0.989
0 .190 6 3/03/50 16:00 0.209 2 32.13 0. 969
0.127 25 2/09/51 2:00 0 .196 3 19.58 0. 949
0 .115 34 10/15/51 13:00 0 .196 4 14. 08 0. 929
0.105 43 3/24/53 15:00 0 .191 5 10.99 0.909
0.123 28 12/19/53 19:00 0.190 6 9.01 0.889
0.130 22 11/25/54 2:00 0.178 7 7. 64 0.869
0.127 24 11/18/55 15:00 0.170 8 6.63 0. 84 9
0 .143 15 12/09/56 14:00 0.160 9 5. 8 6 0. 82 9
0.131 20 12/25/57 16: 00 0.158 10 5.24 0.809
0.100 47 11/03/58 17:00 0.156 11 4.75 0.789
0.123 27 11/20/59 5:00 0.154 12 4.34 0.769
0.110 40 2/14/61 21:00 0.150 13 3.99 0.749
0.114 35 11/22/61 2:00 0.149 14 3.70 0. 729
B-41
SE 14.fn Street -June 2007
0.109 42 12/15/62 2:00 0.143 15 3.44 0.709
0.126 26 12/31/63 23:00 0.140 16 3.22 0.690
D .114 36 12/21/64 4:00 0.138 17 3.03 0. 670
0 .112 38 1/05/66 16:00 0.135 18 2.85 0.650
0.170 8 11/13/66 19:00 0.134 19 2.70 0.630
0.191 5 8/24/68 16:00 0.131 20 2.56 0.610
0.102 44 12/03/68 16:00 0.130 21 2.44 0.590
0 .113 37 1/13/70 22:00 0.130 22 2.32 0.570
o .111 39 12/05/70 9:00 0.129 23 2 .22 0.550
0.156 11 12/08/71 18:00 0 .127 24 2 .13 0.530
0.101 46 1/13/73 2:00 0.127 25 2.04 0.510
0 .116 33 11/28/73 9:00 0.126 26 1. 96 o. 4 90
0.149 14 12/26/74 23:00 0.123 27 1. 89 0.470
0.102 45 11/13/75 19:00 0.123 28 1. 82 0.450
0.129 23 8/26/77 2:00 0.122 29 1. 75 0.430
0.178 7 9/17 /78 2:00 0.120 30 1. 70 0.410
0.160 9 9/08/79 15:00 D .119 31 1. 64 0.390
0.140 16 12/14/79 21: 00 0. 117 32 1. 59 0.370
0.154 12 11/21/80 11: DO D .116 33 1. 54 0.350
0.210 1 10/06/81 0:00 D .115 34 1. 4 9 0.330
0.158 10 10/28/82 16:00 0 .114 35 1. 45 0.310
D .119 31 1/03/84 1:00 0.114 36 1. 41 0. 2 91
0 .110 41 6/06/85 22:00 0.113 37 1. 37 o. n1
0.135 18 1/18/86 16:00 0 .112 38 1. 33 0.251
0 .196 3 10/26/86 0:00 0 .111 39 1. 30 0.231
0. 0 94 49 11/11/87 0:00 0 .110 40 1. 27 0 .211
0.122 29 8/21/89 17:00 0 .110 41 1.24 0 .191
0.209 2 1/09/90 6:00 0.109 42 1. 21 0 .171
0 .196 4 11/24/90 8:00 0.105 43 1.18 0.151
0.117 32 1/27/92 15:00 0.102 44 1.15 0.131
0.086 50 11/01/92 16: 00 0.102 45 1.12 0 .111
0.097 48 11/30/93 22:00 0.101 46 1.10 0. 091
0.120 30 11/30/94 4:00 0.100 47 1. 08 0.071
0.138 17 2/08/96 10:00 0.097 48 1. 05 0.051
0.134 19 1/02/97 6:00 0.094 49 1. 03 0.031
0.150 13 10/04/97 15:00 0.086 50 1. 01 0. 011
Computed Peaks 0.238 100.00 0.990
Computed Peaks 0.219 50.00 0.980
Computed Peaks 0.200 25.00 0. 960
Computed Peaks 0.175 10.00 0.900
Computed Peaks 0 .170 8.00 0.875
Computed Peaks 0.156 5.00 0.800
Computed Peaks 0.128 2.00 0.500
Computed Peaks 0.110 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-52.tsf Mean= -0.457 StdDev= 0 .118
Project Location:Sea-Tac Skew= 0.538
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0.357 21 2/16/49 21:00 0.701 1 8 9. 50 0. 989
0.701 1 3/03/50 16: 00 0.669 2 32 .13 0. 969
0.397 15 2/09/51 2:00 0.592 3 19.58 0. 94 9
0.278 40 10/15/51 13: 00 0.563 4 14. 08 0.929
0.270 45 3/24/53 15:00 0.500 5 10.99 0.909
0.335 26 12/19/53 19:00 0.488 6 9. 01 0.889
0.338 24 11/25/54 2:00 0.484 7 7.64 0.869
0.340 23 12/20/55 17:00 0.452 8 6.63 0.849
B-41
SE 144'1' Street-June 2007
0.394 17 12/09/56 14:00 0.448 9 5. 86 0.829
0.345 22 12/25/57 16:00 0.427 10 5.24 0.809
0.267 46 1/26/59 20:00 0.423 11 4.75 0.789
0.333 27 11/20/59 5:00 0.405 12 4. 34 0.769
0.317 30 2/14/61 21: 00 0.404 13 3.99 0.749
0.289 38 11/22/61 2:00 0.402 14 3.70 0. 72 9
0.299 35 12/15/62 2:00 0.397 15 3.44 0.709
0.336 25 12/31/63 2 3: 00 0.396 16 3.22 0.690
0.295 37 12/21/64 4:00 0.394 17 3.03 0.670
0.298 36 1/05/66 16:00 0.389 18 2.85 0.650
0.452 8 11/13/66 19:00 0.387 19 2.70 0.630
0.488 6 8/24/68 16: 00 0.374 20 2.56 0.610
0.272 42 12/03/68 16:00 0.357 21 2.44 0.590
0.300 34 1/13/70 22:00 0.345 22 2. 32 0.570
0.286 39 12/06/70 8:00 0.340 23 2.22 0.550
0.500 5 2/27 /72 7:00 0.338 24 2.13 0.530
0.265 47 1/13/73 2:00 0.336 25 2. 04 0.510
0.320 28 11/28/73 9:00 0.335 26 1. 96 0. 4 90
0.423 11 12/26/74 23:00 0.333 27 1.89 0.470
0. 271 43 12/02/75 20:00 0.320 28 1. 82 0.450
0.312 31 8/26/77 2:00 0.319 29 1. 7 5 0.430
0.427 10 9/17/78 2:00 0.317 30 1. 70 0.410
0.374 20 9/08/79 15:00 0.312 31 1. 64 0.390
0.387 19 12/14/79 21:00 0.310 32 1. 59 0.370
0.404 13 11/21/80 11: 00 0.307 33 1. 54 0.350
0.563 4 10/06/81 0:00 0.300 34 1. 4 9 0.330
0. 396 16 10/28/82 16:00 0.299 35 1. 45 0.310
0.319 29 1/03/84 1:00 0.298 36 1. 41 0. 2 91
0.270 44 6/06/85 22: 00 0.295 37 1. 37 0.271
0.389 18 1/18/86 16:00 0.289 38 1. 33 0.251
0.484 7 10/26/86 0:00 0.286 39 1. 30 0.231
0.212 49 11/11/87 0:00 0.278 40 1.27 0. 211
0.275 41 8/21/89 17:00 0.275 41 1. 24 0.191
0.669 2 1/09/90 6:00 0.272 42 1.21 0.171
0.592 3 11/24/90 8:00 0.271 43 1.18 0.151
0.310 32 1/27 /92 15:00 0. 270 44 1.15 0.131
0.199 50 11/01/92 16: 00 0.270 45 1.12 0 .111
0.232 48 11/30/93 22 :00 0. 2 67 46 1.10 0.091
0.307 33 11/30/94 4:00 0. 2 65 47 1. 08 0 .071
0.448 9 2/08/96 10:00 0. 232 48 1. 05 0.051
0.402 14 1/02/97 6:00 0.212 49 1.03 0.031
0.405 12 10/04/97 15:00 0.199 50 1. 01 0.011
Computed Peaks 0.729 100.00 0.990
Computed Peaks 0.657 50.00 0.980
Computed Peaks 0.588 25.00 0. 960
Computed Peaks 0.501 10.00 0.900
Computed Peaks 0.483 8.00 0.875
Computed Peaks 0.435 5.00 0.800
Computed Peaks 0.341 2.00 0.500
Computed Peaks 0.283 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-54.tsf Mean= -0.367 StdDev-0 .117
Project Location:Sea-Tac Skew= 0.588
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0.437 21 2/16/49 21 :00 0.876 1 89.50 0. 989
0.876 1 3/03/50 16:00 0.818 2 32.13 0. 969
B-43
SE I 44'n Street-June 2007
0.493 14 2/09/51 2:00 0.720 3 19.58 0.949
0.345 40 10/15/51 13:00 0.687 4 14. 08 0. 929
0.332 44 3/24/53 15:00 0.622 5 10.99 0.909
0. 411 26 12/19/53 19:00 0.600 6 9.01 0.889
0.415 24 11/25/54 2: 00 0.598 7 7.64 0.869
0.420 23 12/20/55 17:00 0.556 8 6.63 0.849
0.480 17 12/09/56 14: 00 0.552 9 5. 86 0.829
0.422 22 12/25/57 16:00 0.530 10 5.24 0.809
0.332 45 1/26/59 20:00 0.513 11 4.75 0.789
0.407 27 11/20/59 5:00 0.498 12 4.34 0.769
0.395 28 2/14/61 21:00 0.494 13 3.99 0. 749
0.356 38 11/22/61 2:00 0.493 14 3.70 0.729
0.366 35 12/15/62 2:00 0.493 15 3.44 0.709
0.415 25 12/31/63 23:00 0.488 16 3.22 0.690
0.363 37 12/21/64 4:00 0.480 17 3.03 0.670
0.365 36 1/05/66 16:00 0.473 18 2.85 0.650
0.552 9 11/13/66 19:00 0.470 19 2.70 0.630
0.600 6 8/24/68 16:00 0.466 20 2.56 0.610
0.333 43 12/03/68 16:00 0.437 21 2.44 0.590
0.367 34 1/13/70 22 :00 0.422 22 2. 32 0.570
0.350 39 12/06/70 8:00 0.420 23 2 .22 0.550
0.622 5 2/27 /72 7:00 0.415 24 2. 13 0.530
0. 327 47 1/13/73 2:00 0.415 25 2.04 0.510
0.389 30 11/28/73 9:00 0.411 26 1. 96 0. 4 90
0.513 11 12/26/74 23:00 0.407 27 1. 89 0.470
0.332 46 12/02/75 20:00 0.395 28 1. 82 0.450
0.386 31 8/26/77 2:00 0. 391 29 1. 75 0.430
0.530 10 9/17 /78 2:00 0.389 30 1. 70 0.410
0. 4 66 20 9/08/79 15:00 0.386 31 1. 64 0. 390
0.470 19 12/14/79 21 :00 0. 37 9 32 1. 59 0.370
0. 4 94 13 11/21/80 11 :00 0.377 33 1. 54 0.350
0.687 4 10/06/81 0:00 0.367 34 1.49 0.330
0.488 16 10/28/82 16:00 0.366 35 1. 45 0.310
0.391 29 3/15/84 20:00 0.365 36 1. 41 0. 291
0.334 42 6/06/85 22:00 0.363 37 1. 37 0.271
0.473 18 1/18/86 16:00 0.356 38 1. 33 0.251
0.598 7 10/26/86 0: 00 0.350 39 1. 30 0.231
0.266 49 11/11/87 0: 00 0.345 40 1.27 0. 211
0.345 41 8/21/89 17:00 0.345 41 1. 24 0 .191
0.818 2 1/09/90 6:00 0.334 42 1. 21 0.171
0. 720 3 11/24/90 8:00 0.333 43 1.18 0.151
0. 37 9 32 1/27/92 15:00 0.332 44 1.15 0.131
0.248 50 11/01 / 92 16: 00 0.332 45 1.12 0 .111
0.288 48 11/30/93 22:00 0.332 46 1.10 0.091
0.377 33 11/30/94 4:00 0 .327 47 1. 08 0.071
0. 55 6 8 2/08/96 10:00 0.288 48 1. 05 0.051
0. 4 98 12 1/02/97 6:00 0. 2 66 49 1. 03 0.031
0. 4 93 15 10/04/97 15:00 0.248 50 1. 01 0.011
Computed Peaks 0.902 100.00 0.990
Computed Peaks 0. 811 50.00 0.980
Computed Peaks 0.724 25.00 0. 960
Computed Peaks 0.615 10.00 0.900
Computed Peaks 0.593 8.00 0.875
Computed Peaks 0.534 5.00 0.800
Computed Peaks 0.419 2.00 0.500
Computed Peaks 0. 34 9 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-60.tsf Mean= -0.876 StdDev-0 .096
Project Location:Sea-Tac Skew= 0.561
B-44
SE 14(" Street-June 2007
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0.133 21 2/16/49 21:00 0.214 1 89.50 0.989
0.193 6 3/03/50 16:00 0. 213 2 32.13 0. 969
0.129 25 2/09/51 2:00 0.201 3 19.58 0. 94 9
0 .117 34 10/15/51 13:00 0.200 4 14.08 0. 92 9
0.107 43 3/24/53 15:00 0 .195 5 10.99 0. 909
0.125 27 12/19/53 19: 00 0 .193 6 9.01 0.889
0 .133 22 11/25/54 2:00 0.181 7 7.64 0.869
0.130 24 11/18/55 15:00 0.173 8 6.63 0. 84 9
0.146 15 12/09/56 14:00 0 .163 9 5.86 0. 82 9
0 .133 20 12/25/57 16: 00 0.162 10 5.24 0.809
0.102 47 11/03/58 17:00 0.159 11 4.75 0.789
0.125 28 11/20/59 5:00 0.157 12 4.34 0.769
0 .112 40 2/14/61 21:00 0.153 13 3.99 0. 749
0 .116 35 11/22/61 2:00 0.152 14 3.70 0.729
0 .111 42 12/15/62 2:00 0 .146 15 3.44 0.709
0.128 26 12/31/63 23:00 0.143 16 3.22 0.690
0 .116 36 12/21/64 4:00 0.140 17 3.03 0.670
0 .115 38 1/05/66 16: 00 0.138 18 2.85 0.650
0 .173 8 11/13/66 19: 00 0.137 19 2.70 0.630
0.195 5 8/24/68 16:00 0.133 20 2.56 0.610
0.104 44 12/03/68 16:00 0.133 21 2.44 0.590
0 .116 37 1/13/70 22:00 0.133 22 2. 32 0.570
0 .113 39 12/05/70 9:00 0.132 23 2.22 0.550
0.159 11 12/08/71 18:00 0 .130 24 2.13 0.530
0.103 46 1/13/73 2:00 0.129 25 2.04 0.510
0 .118 33 11/28/73 9:00 0.128 26 1. 96 0.490
0 .152 14 12/26/74 23:00 0.125 27 1. 89 0.470
0.104 45 11/13/75 19: 00 0.125 28 1. 82 0.450
0.132 23 8/26/77 2:00 0.124 29 1. 7 5 0.430
0.181 7 9/17/78 2:00 0.123 30 1.70 0.410
0.163 9 9/08/79 15:00 0.121 31 1. 64 0.390
0.143 16 12/14/79 21:00 0.120 32 1. 59 0.370
0.157 12 11/21/80 11: 00 0 .118 33 1. 54 0.350
0. 214 1 10/06/81 0:00 0 .117 34 1. 4 9 0.330
0.162 10 10/28/82 16:00 0 .116 35 1. 45 0.310
0.121 31 1/03/84 1:00 0 .116 36 1. 41 0. 291
0 .112 41 6/06/85 22:00 0 .116 37 1. 37 0.271
0.138 18 1/18/86 16:00 0.115 38 1. 33 0.251
0.201 3 10/26/86 0:00 0 .113 39 1. 30 0.231
0 .096 49 11/11/87 0:00 0 .112 40 1. 27 0 .211
0.124 29 8/21/89 17:00 0 .112 41 1. 24 0 .191
0. 213 2 1/09/90 6:00 0 .111 42 1.21 0 .171
0.200 4 11/24/90 8: 00 0.107 43 1.18 0.151
0.120 32 1/27 /92 15:00 0.104 44 1.15 0.131
0.087 50 11/01/92 16:00 0.104 45 1.12 0 .111
0.099 48 11/30/93 22:00 0.103 46 1.10 0. 091
0.123 30 11/30/94 4:00 0.102 47 1. 08 0. 071
0.140 17 2/08/96 10:00 0.099 48 1. 05 0.051
0.137 19 1/02/97 6:00 0.096 49 1. 03 0.031
0.153 13 10/04/97 15:00 0.087 50 1. 01 0. 011
Computed Peaks 0.243 100.00 0.990
Computed Peaks 0.223 50.00 0.980
Computed Peaks 0.204 25.00 0. 960
Computed Peaks 0.178 10.00 0. 900
Computed Peaks 0.173 8. 00 0.875
Computed Peaks 0.159 5.00 0.800
B-45
SE J4,(h Street-June 2007
Computed Peaks 0.130 2.00 0.500
Computed Peaks 0 .112 1.30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-70.tsf Mean= -0. 327 StdDev= 0.133
Project Locacion:Sea-Tac Skew= 0.509
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0. 4 92 20 2/16/49 21: 00 1. 06 1 8 9. 50 0.989
1. 06 1 3/03/50 16:00 0.988 2 32.13 0. 969
0.578 11 2/09/51 2:00 o. s 61 3 19.58 0.949
0.353 45 1/30/52 8:00 0.781 4 14.08 0. 92 9
0.354 44 3/24/53 15:00 0.729 5 10.99 o. 90 9 o. 454 25 12/19/53 19:00 0.667 6 9.01 0.889
0.470 22 2/07/55 17:00 0.635 7 7.64 0.869
0.485 21 12/20/55 17:00 0.610 8 6.63 0.849
D. 54 9 16 12/09/56 14: 00 0.607 9 5.86 0.829
0.462 23 12/25/57 16:00 0.604 10 5.24 0.809
0. 361 42 1/26/59 20:00 0.578 11 4.75 0.789
0.461 24 11/20/59 5:00 0.568 12 4.34 0.769
0.432 30 2/14/61 21:00 0. 562 13 3.99 0.749
0.376 39 11/22/61 2:00 0.557 14 3.70 0. 729
D. 411 32 12/15/62 2:00 0.551 15 3.44 0.709
0.451 26 12/31/63 23:00 0. 54 9 16 3.22 0.690
0. 38 9 37 12/21/64 4:00 0.540 17 3.03 0. 670
0.402 34 1/05/66 16: 00 0.536 18 2.85 0.650
0.610 8 11/13/66 19: 00 0.508 19 2.70 0.630
0.635 7 8/24/68 16:00 0. 4 92 20 2.56 0. 610
0. 371 41 12/03/68 16:00 0.485 21 2.44 0. 590
0.405 33 1/13/70 22:00 0.470 22 2.32 0.570
0. 396 36 12/06/70 8: 00 0. 462 23 2.22 0.550
0.729 5 2/27 /72 7:00 0.461 24 2 .13 0.530
0.355 43 1/13/73 2:00 0.454 25 2.04 0.510
0. 441 28 11/28/73 9:00 0.451 26 1. 96 0.490
0.604 10 12/26/74 23:00 0.450 27 1. 8 9 0.470
0.373 40 12/02/75 20:00 D. 441 28 1. 82 0.450
0.385 38 8/26/77 2:00 0.436 29 1. 75 0. 430
0.557 14 9/22/78 19:00 0.432 30 1. 70 0.410
0.450 27 9/08/79 15:00 0.416 31 1. 64 0.390
0.536 18 12/14/79 21:00 0. 411 32 1. 59 0.370
0.540 17 11/21/80 11: 00 0.405 33 1. 54 0.350
0.781 4 10/06/81 15:00 0.402 34 1. 4 9 0.330
0.508 19 10/28/82 16: 00 0.401 35 1. 45 0.310
0.436 29 3/15/84 20:00 0.396 36 1. 41 0.291
0.340 46 6/06/85 22 :00 0.389 37 1. 37 0. 271
0.562 13 1/18/86 16: 00 0.385 38 1. 33 0.251
0.607 9 10/26/86 0:00 0.376 39 1. 30 0.231
0. 2 67 49 1/14/88 0:00 0.373 40 1. 27 0. 211
0.321 47 8/21/89 17:00 0.371 41 1. 24 0.191
0.988 2 1/09/90 6: DO 0.361 42 1. 21 0.171
0.861 3 11/24/90 8:00 0.355 43 1. 18 0.151
0.416 31 1/27/92 15:00 0.354 44 1. 15 0.131
0.249 50 12/10/92 6:00 0.353 45 1.12 0.111
0.283 48 11/30/93 22:00 0.340 46 1.10 0.091
0.401 35 11/30/94 4:00 0.321 47 1. 08 0.071
0.667 6 2/08/96 10:00 0.283 48 1. 05 0.051
0.568 12 1/02/97 6: 00 0. 2 67 49 1. 03 0.031
0.551 15 10/04/97 15:00 0.249 50 1. 01 0. 011
B-46
SE I 44h Street-June 2007
Computed Peaks 1. 08 100.00 0.990
Computed Peaks 0.958 SO.OD 0.980
Computed Peaks 0.847 25.00 0.960
Computed Peaks 0.707 10.00 0.900
Computed Peaks 0.680 8.00 0.875
Computed Peaks 0.604 5.00 0.800
Computed Peaks 0.459 2.00 0.500
Computed Peaks 0.371 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-80.tsf Mean= 0.090 StdOev-0.131
Project Location:Sea-Tac Skew-0.500
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
1. 34 18 2/16/49 21:00 2.61 1 89.50 0.989
2.57 2 3/03/50 16:00 2.57 2 32 .13 0. 969
1. 51 11 2/09/51 2:00 2.31 3 19.58 0.949
0.958 41 1/30/52 8:00 2.05 4 14. 08 0. 929
0. 92 6 44 3/24/53 15:00 1.84 5 10.99 0.909
1.19 25 12/19/53 19:00 1. 77 6 9.01 0.889
1. 28 21 2/07/55 17:00 1. 65 7 7.64 0.869
1. 30 20 12/20/55 17:00 1. 59 8 6.63 0. 84 9
1. 48 13 12/09/56 14:00 1. 58 9 5.86 0. 82 9
1. 20 24 12/25/57 16:00 1. 53 10 5.24 0.809
0.915 45 1/26/59 20:00 1. 51 11 4.75 0.789
1. 24 23 11/20/59 5:00 1. 51 12 4.34 0. 7 69
1. 09 31 2/14/61 21:00 1. 4 8 13 3. 99 0.749
0.938 43 11/22/61 2:00 1. 47 14 3. 70 0.729
1. 08 32 12/15/62 2:00 1. 41 15 3.44 0.709
1.19 26 12/31/63 23:00 1. 38 16 3 .22 0.690
1. 02 37 12/21/64 4:00 1. 36 17 3.03 0.670
1. 08 34 1/05/66 16:00 1. 34 18 2. 85 0.650
1. 51 12 11/13/66 19:00 1. 34 19 2.70 0.630
1.59 8 8/24/68 16:00 1. 30 20 2.56 0.610
1. 01 39 12/03/68 16:00 1. 28 21 2.44 0.590
1. 08 33 1/13/70 22:00 1. 27 22 2.32 0.570
1. 05 35 12/06/70 8:00 1.24 23 2.22 0.550
1. 84 5 2/27/72 7:00 1. 20 24 2.13 0.530
0.954 42 1/13/73 2:00 1.19 25 2.04 0.510
1. 14 28 11/28/73 9:00 1.19 26 1. 96 0. 4 90
1. 65 7 12/26/74 23:00 1.15 27 1. 89 0.470
1. 02 36 12/02/75 20:00 1.14 28 1. 82 0.450
0.972 40 8/26/77 2:00 1.14 29 1. 75 0.430
1. 38 16 9/22/78 19:00 1.10 30 1. 70 0.410
1.14 29 9/08/79 15:00 1. 09 31 1. 64 0.390
1. 41 15 12/14/79 21:00 1. 08 32 1. 59 0.370
1. 34 19 11/21/80 11:00 1. 08 33 1. 54 0.350
2.05 4 10/06/81 15:00 1. 08 34 1. 4 9 0.330
1.27 22 10/28/82 16:00 1. 05 35 1. 45 0.310
1. 15 27 1/03/84 1:00 1. 02 36 1. 41 0. 2 91
0.858 46 6/06/85 22:00 1. 02 37 1. 37 0.271
1. 58 9 1/18/86 16: OD 1. 02 38 1. 33 0.251
1. 53 10 10/26/86 0:00 1. 01 39 1. 30 0.231
0.707 49 1/14/88 12:00 0. 972 40 1. 27 0. 211
0.815 47 8/21/89 17:00 0.958 41 1.24 0 .191
2.61 1 1/09/90 6:00 0.954 42 1. 21 0 .171
2.31 3 11/24/90 8:00 0.938 43 1.18 0.151
1. 10 30 1/27 /92 15:00 0. 926 44 1. 15 0.131
B-47
SE 14¢1' Street-June 2007
0. 692 50 3/22/93 22:00 0.915 45 1.12 0 .111
0.717 48 11/30/93 22:00 0.858 46 1. 10 0. 091
1. 02 38 11/30/94 4:00 0.815 47 1. 08 0. 071
1. 77 6 2/08/96 10:00 0. 717 48 1. 05 0.051
1.47 14 1/02/97 6:00 0.707 49 1. 03 0.031
1. 3 6 17 10/04/97 15:00 0. 692 50 1. 01 0. 011
Computed Peaks 2.76 100.00 0.990
Computed Peaks 2.47 50.00 0.980
Computed Peaks 2.19 25.00 0. 960
Computed Peaks 1. 83 10.00 0.900
Computed Peaks 1. 76 8.00 0.875
Computed Peaks 1. 57 5.00 0.800
Computed Peaks 1. 20 2.00 0.500
Computed Peaks 0.973 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-90.tsf Mean= -0.989 StdDev-0.096
Project Location:Sea-Tac Skew= 0.559
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate RanK Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0.102 21 2/16/49 21:00 0.164 1 89.50 0.989
0.148 6 3/03/50 16:00 0.164 2 32 .13 0.969
0.099 25 2/09/51 2:00 0.155 3 19.58 0.949
0.090 34 10/15/51 13:00 0.155 4 14.08 0. 929
0.082 43 3/24/53 15:00 0.150 5 10.99 0.909
0. 096 28 12/19/53 19:00 0 .148 6 9.01 0.889
0.102 22 11/25/54 2:00 0 .139 7 7. 64 0.869
0.100 24 11/18/55 15:00 0.133 8 6.63 0.849
0 .112 15 12/09/56 14:00 0.125 9 5.86 0. 829
0.103 20 12/25/57 16:00 0.124 10 5.24 0.809
0.078 47 11/03/58 17:00 0.123 11 4.75 0.789
0.097 27 11/20/59 5:00 0.121 12 4. 34 0.769
0.086 40 2/14/61 21: 00 0 .118 13 3.99 0.749
0.090 35 11/22/61 2:00 0 .117 14 3.70 0. 72 9
0.085 42 12/15/62 2:00 0 .112 15 3.44 0.709
0.099 26 12/31/63 23:00 0 .110 16 3.22 0.690
0.089 36 12/21/64 4:00 0.108 17 3.03 0. 670
0.088 38 1/05/66 16:00 0.106 18 2.85 0.650
0.133 8 11/13/66 19:00 0.105 19 2.70 0.630
0.150 5 8/24/68 16:00 0.103 20 2.56 0.610
0.080 44 12/03/68 16:00 0.102 21 2.44 0.590
0.089 37 1/13/70 22:00 0.102 22 2.32 0.570
0.087 39 12/05/70 9:00 0.101 23 2. 22 0.550
0.123 11 12/08/71 18:00 0.100 24 2.13 0.530
0.080 46 1/13/73 2:00 0.099 25 2. 04 0.510
0.091 33 11/28/73 9:00 0.099 26 1. 96 0.490
0 .117 14 12/26/74 23:00 0. 097 27 1. 89 0.470
0.080 45 11/13/75 19:00 0. 096 28 1. 82 0.450
0.101 23 8/26/77 2:00 0.095 29 1. 75 0.430
0.139 7 9/17 /78 2:00 0.095 30 1. 70 0.410
0.125 9 9/08/79 15:00 0.093 31 1. 64 0.390
0 .110 16 12/14/79 21:00 0. 0 92 32 1. 59 0.370
0.121 12 11/21/80 11:00 0.091 33 1. 54 0.350
0.164 1 10/06/81 0:00 0.090 34 1. 4 9 0.330
0.124 10 10/28/82 16:00 0.090 35 1. 45 0.310
0.093 31 1/03/84 1:00 0.089 36 1. 41 0. 291
0.086 41 6/06/85 22:00 0.089 37 1. 37 0.271
0.106 18 1/18/86 16: DO 0.088 38 1. 33 0.251
B-48
SE J 4,th Street -June 2007
0.155 3 10/26/86 0:00 0.087 39 1. 30 0.231
0.074 49 11/11/87 0:00 0.086 40 1.27 0.211
0.095 29 8/21/89 17:00 0.086 41 1. 24 0.191
0.164 2 1/09/90 6:00 0.085 42 1. 21 0.171
0.155 4 11/24/90 8:00 0.082 43 1. 18 0.151
0. 092 32 1/27/92 15:00 0.080 44 1.15 0.131
0.067 50 11/01/92 16: 00 0.080 45 1.12 0 .111
0.076 48 11/30/93 22:00 0.080 46 1. 10 0.091
0.095 30 11 /30 / 94 4:00 0.078 47 1. 08 0. 071
0.108 17 2/08/96 10:00 0. 07 6 48 1. 05 0.051
0.105 19 1/02/97 6:00 0.074 49 1. 03 0.031
0 .118 13 10/04/97 15:00 0. 067 50 1. 01 0. 011
Computed Peaks 0.187 100.00 0.990
Computed Peaks 0.172 50.00 0.980
Computed Peaks 0.157 25.00 0. 960
Computed Peaks 0.137 10.00 0.900
Computed Peaks 0.133 8.00 0.875
Computed Peaks 0.122 5.00 0.800
Computed Peaks 0.100 2.00 0.500
Computed Peaks 0.086 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-100.tsf Mean= -1. 001 StdDev~ 0. 167
Project Location:Sea-Tac Skew= 0.401
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0 .113 18 2/16/49 21: 00 0.250 1 8 9. 50 0.989
0.250 1 3/03/50 16:00 0. 24 9 2 32.13 0.969
0.138 9 2/09/51 2:00 0.216 3 19. 58 0. 94 9
0.078 38 1/30/52 8:00 0.188 4 14.08 0. 92 9
0.069 42 3/24/53 15:00 0.169 5 10.99 0. 909
0. 096 23 12/19/53 19:00 0. 169 6 9.01 0.889
0 .113 19 2/07/55 17:00 0.149 7 7. 64 0.869
0 .117 16 12/20/55 17:00 0.147 8 6.63 0.849
0 .127 13 12/09/56 14:00 0.138 9 5.86 0.829
0.094 25 12/25/57 16:00 0.132 10 5.24 0.809
0.073 41 1/26/59 20:00 0.129 11 4.75 0.789
0.121 14 11/20/59 21:00 0.129 12 4.34 0.769
0.088 31 2/14/61 21:00 0 .127 13 3.99 0.749
0.068 43 11/22/61 2:00 0.121 14 3.70 0. 72 9
0.091 28 12/15/62 2:00 0.120 15 3.44 0.709
0.094 26 12/31/63 23:00 0 .117 16 3.22 0.690
0. 077 39 12/21/64 4:00 0 .115 17 3.03 0. 670
0.086 34 1/05/66 16:00 0.113 18 2.85 0.650
0.129 11 1/19/67 14:00 0 .113 19 2.70 0.630
0 .115 17 8/24/68 16:00 0 .111 20 2.56 0.610
0.084 36 12/03/68 16:00 0.105 21 2. 44 0.590
0.088 32 1/13/70 22:00 0.105 22 2.32 0.570
0.089 29 12/06/70 8: DO 0.096 23 2.22 0.550
0.169 5 2/27 /72 7:00 0. 096 24 2.13 0.530
0.075 40 1/13/73 2:00 0.094 25 2.04 0.510
0.096 24 11/28/73 9: 00 0.094 26 1. 96 0. 4 90
0.149 7 12/26/74 23:00 0.093 27 1. 89 0.470
0.086 35 12 /02 /7 5 20:00 0. 091 28 1. 82 0.450
0.060 45 8/26/77 2:00 0.089 29 1. 75 0.430
0.105 21 9/22/78 19:00 0.088 30 1. 70 0.410
0.064 44 9/08/79 15:00 0.088 31 1. 64 0.390
0.120 15 12/14/79 21:00 0.088 32 1. 59 0.370
B-49
SE !4(hStreet-June2007
0.105 22 11/21/80 11 :00 0.087 33 1. 54 0.350
0.188 4 10/06/81 15:00 0.086 34 1. 4 9 0.330
0.088 30 10/28/82 16: 00 0.086 35 1. 45 0.310
0.093 27 1/03/84 1:00 0.084 36 1. 41 0. 2 91
0.056 48 6/06/85 22:00 0.081 37 1. 37 0.271
0 .14 7 8 1/18/86 16: 00 0.078 38 1. 33 0.251
0.132 10 11/24/86 3:00 0.077 39 1. 30 0. 2 31
0.059 47 1/14/88 12:00 0.075 40 1.27 0. 211
0.055 49 11/05/88 14:00 0.073 41 1. 24 0 .191
0.249 2 1/09/90 6:00 0.069 42 1. 21 0 .171
0.216 3 11/24/90 8:00 0.068 43 1. 18 0.151
0.087 33 1/27/92 15:00 0.064 44 1.15 0.131
0.060 46 3/22/93 22:00 0.060 45 1. 12 0 .111
0.043 50 11/30/93 22:00 0.060 46 1.10 0.091
0.081 37 12/27/94 1:00 0.059 47 1. 08 0.071
0.169 6 2/08/96 10:00 0.056 48 1. 05 0.051
0.129 12 1/02/97 6:00 0.055 49 1.03 0.031
0 .111 20 10/04/97 15:00 0.043 50 1. 01 0. 011
Computed Peaks 0 .273 100.00 0.990
Computed Peaks 0.239 50.00 0.980
Computed Peaks 0.206 25.00 0.960
Computed Peaks 0.166 10.00 0.900
Computed Peaks 0.158 8.00 0.875
Computed Peaks 0.137 5.00 0.800
Computed Peaks 0.097 2.00 0.500
Computed Peaks 0.074 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-106.tsf Mean= 0.164 StdDev~ 0.122
Project Location:Sea-Tac Skew= 0. 511
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CF"S) (CFS) Period
1. 52 20 2/16/49 21:00 3.02 1 89.50 0.989
3.02 1 3/03/50 16: 00 2.88 2 32. 13 0. 969
1. 73 12 2/09/51 2:00 2.54 3 19.58 0.949
1.13 42 10/15/51 13: 00 2. 2 9 4 14.08 0. 92 9
1. 12 44 3/24/53 15:00 2.15 5 10.99 0.909
1. 40 27 12/19/53 19:00 1. 98 6 9.01 0.889
1. 44 23 2/07/55 17:00 1. 98 7 7. 64 0.869
1. 4 7 22 12/20/55 17:00 1. 96 8 6.63 0.849
1. 67 15 12/09/56 14:00 1. 84 9 5. 8 6 0.829
1. 43 24 12/25/57 16: 00 1. 80 10 5.24 0.809
1.12 43 1/26/59 20:00 1. 73 11 4.75 0.789
1. 41 25 11/20/59 5:00 1. 7 3 12 4.34 0. 7 69
1. 33 29 2/14/61 21:00 1. 72 13 3.99 0.749
1.17 39 11/22/61 2:00 1. 70 14 3.70 0.729
1. 25 34 12/15/62 2:00 1. 67 15 3.44 0.709
1. 41 26 12/31/63 23:00 1. 65 16 3.22 0.690
1. 22 37 12/21/64 4: 00 1. 65 17 3.03 0.670
1. 25 36 1/05/66 16:00 1. 62 18 2.85 0.650
1. 84 9 11/13/66 19:00 1. 61 19 2.70 0.630
1. 98 6 8/24/68 16: 00 1. 52 20 2.56 0.610
1.15 41 12/03/68 16:00 1. 51 21 2.44 0.590
1. 2 6 33 1/13/70 22:00 1. 4 7 22 2.32 0.570
1. 20 38 12/06/70 8:00 1. 44 23 2.22 0.550
2.15 5 2/27/72 7:00 1. 43 24 2.13 0.530
1.12 45 1/13/73 2:00 1. 41 25 2.04 0.510
1. 33 30 11/28/73 9:00 1. 41 26 1. 96 0. 4 90
B-50
SE I 44n Street -June 2007
1. 80 10 12/26/74 23:00 1. 40 27 1. 89 0. 47 0
1. 16 40 12/02/75 20:00 1. 34 28 1. 82 0.450
1. 26 32 8/26/77 2:00 1. 33 29 1. 75 0.430
1. 73 11 9/17 /78 2:00 1. 33 30 1. 70 0.410
1. 51 21 9/08/79 15:00 1. 2 9 31 1. 64 0.390
1. 62 18 12/14/79 21: 00 1. 2 6 32 1. 59 0.370
1. 65 16 11/21/80 11: 00 1. 2 6 33 1. 54 0.350
2.29 4 10/06/81 0:00 1. 25 34 1. 4 9 0.330
1. 61 19 10/28/82 16:00 1.25 35 1. 45 0.310
1. 34 28 1/03/84 1:00 1. 25 36 1. 41 0.291
1.10 47 6/06/85 22:00 1. 22 37 1.37 0.271
1. 70 14 1/18/86 16:00 1. 20 38 1. 33 0.251
1. 96 8 10/26/86 0:00 1. 17 39 1.30 0.231
0.857 49 11/11/87 0: 00 1.16 40 1.27 0.211
1.11 46 8/21/89 17:00 1. 15 41 1. 24 0 .191
2.88 2 1/09/90 6: DO 1.13 42 1. 21 0.171
2.54 3 11/24/90 8:00 1.12 43 1. 18 0.151
1. 29 31 1/27 /92 15:00 1.12 44 1. 15 0.131
0.804 50 11/01/92 16:00 1.12 45 1. 12 0 .111
0.937 48 11/30/93 22:00 1.11 46 1. 10 0. 091
1. 25 35 11/30/94 4:00 1.10 47 1. 08 0.071
1. 98 7 2/08/96 10:00 0.937 48 1. 05 0.051
1. 72 13 1/02/97 6:00 0.857 49 1. 03 0.031
1. 65 17 10/04/97 15:00 0.804 50 1.01 0. 011
Computed Peaks 3.10 100.00 0.990
Computed Peaks 2. 79 50.00 0.980
Computed Peaks 2.49 25.00 0. 960
Computed Peaks 2.11 10.00 0.900
Computed Peaks 2.04 8.00 0.875
Computed Peaks 1. 83 5.00 0.800
Computed Peaks 1. 42 2. DO 0.500
Computed Peaks 1.17 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-110.tsf Mean= 0.487 StdDev~ 0 .145
Project Location:Sea-Tac Skew= 0.484
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
3.35 20 2/16/49 21: OD 6.91 1 8 9. 50 0.989
6.79 2 3/03/50 16:00 6. 7 9 2 32. 13 0.969
3.89 9 2/09/51 2:00 6 .11 3 19.58 0.949
2.38 40 1/30/52 8:00 5.57 4 14.08 0. 92 9
2.21 44 3/24/53 15:00 4.75 5 10. 99 0.909
2.95 25 12/19/53 19: 00 4.66 6 9.01 0.889
3.27 22 2/07/55 17:00 4.31 7 7. 64 0.869
3.34 21 12/20/55 17:00 4.16 8 6. 63 0. 84 9
3.77 13 12/09/56 14:00 3. 8 9 9 5.86 0. 82 9
2.95 24 12/25/57 16: 00 3. 8 6 10 5.24 0.809
2.22 43 1/26/59 20:00 3.82 11 4.75 0.789
3.38 19 11/20/ 59 21:00 3.80 12 4.34 0.769
2.65 34 2/14/61 21:00 3.77 13 3.99 0.749
2.27 42 11/22/61 2:00 3.74 14 3.70 0. 729
2.73 29 12/15/62 2:00 3.61 15 3.44 0.709
2.91 26 12/31/63 23:00 3. 4 9 16 3.22 0.690
2.47 37 12/21/64 4:00 3.47 17 3.03 0. 670
2.66 33 1/05/66 16: 00 3.41 18 2.85 0.650
3.86 10 11/13/66 19:00 3.38 19 2.70 0.630
3.80 12 8/24/68 16:00 3.35 20 2.56 0.610
B-51
SE 144°' Street-June 2007
2.54 36 12/03/68 16: 00 3.34 21 2.44 0.590
2.70 32 1/13/70 22:00 3.27 22 2. 32 0.570
2.70 31 12/06/70 8:00 3.02 23 2.22 0.550
4.75 5 2/27/72 7:00 2.95 24 2.13 0.530
2.34 41 1/13/73 2:00 2.95 25 2.04 0. 510
2.88 27 11/28/73 9:00 2.91 26 1. 96 0.490
4.31 7 12/26/74 23:00 2.88 27 1. 89 0.470
2.58 35 12/02/75 20:00 2.85 28 1. 82 0. 4 50
2.19 45 8/26/77 2:00 2.73 29 1. 75 0. 430
3.47 17 9/22/78 19:00 2. 71 30 1. 70 0. 410
2. 4 6 39 9/08/79 15:00 2.70 31 1. 64 0.390
3.61 15 12/14/79 21:00 2.70 32 1. 59 0.370
3. 41 18 11/21/80 11 :00 2.66 33 1. 54 0.350
5.57 4 10/06/81 15:00 2. 65 34 1. 49 0.330
3.02 23 10/28/82 16:00 2.58 35 1. 45 0.310
2.85 28 1/03/84 1: 00 2.54 36 1. 41 0.291
1. 97 46 6/06/85 22:00 2.47 37 1. 37 0. 271
4.16 8 1/18/86 16:00 2.47 38 1. 33 0.251
3.82 11 11/24/86 3: 00 2.46 39 1. 30 0.231
1. 7 9 48 1/14/88 12:00 2.38 40 1.27 0. 211
1. 87 47 11/05/88 14:00 2.34 41 1. 24 0.191
6.91 1 1/09/90 6: 00 2.27 42 1. 21 0.171
6.11 3 11/24/90 8:00 2.22 43 1. 18 0.151
2. 71 30 1/27/92 15:00 2.21 44 1. 15 0.131
1. 77 49 3/22/93 22: 00 2.19 45 1. 12 0 .111
1. 58 50 11/30/93 22:00 1. 97 46 1. 10 0.091
2. 47 38 11/30/94 4:00 1. 87 47 1. 08 0. 071
4.66 6 2/08/96 10:00 1. 7 9 48 1. 05 0.051
3.74 14 1/02/97 6:00 1. 77 49 1. 03 0.031
3.49 16 10/04/97 15:00 1. 58 50 1. 01 0. 011
Computed Peaks 7. 4 6 100.00 0.990
Computed Peaks 6.60 50.00 0.980
Computed Peaks 5.78 25.00 0. 960
Computed Peaks 4.76 10.00 0.900
Computed Peaks 4.56 8.00 0.875
Computed Peaks 4.01 5.00 0.800
Computed Peaks 2.99 2.00 0.500
Computed Peaks 2.37 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-120.tsf Mean= -0.565 StdDev~ 0.101
Project Location:Sea-Tac Skew= 0.475
---Annual Peak E'low Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0.277 21 2/16/49 21:00 0. 4 67 1 89.50 0.989
0.426 4 3/03/50 16:00 0.443 2 32.13 0. 969
0.280 20 2/09/51 2:00 0.434 3 19.58 0.949
0.231 38 10/15/51 13:00 0.426 4 14. 08 0. 929
0.214 45 3/24/53 15:00 0. 391 5 10.99 0.909
0.258 27 12/19/53 19: 00 0.386 6 9.01 0.889
0.272 23 11/25/54 2:00 0.355 7 7.64 0.869
0. 2 62 25 11/18/55 15:00 0.351 8 6.63 0. 84 9
0.306 16 12/09/56 14:00 0.336 9 5.86 0.829
0 .272 22 12/25/57 16: 00 0.324 10 5.24 0.809
0.208 47 11/18/58 13:00 0.322 11 4.75 0.789
0. 2 64 24 11/20/59 5:00 0.320 12 4.34 0. 7 69
0.230 39 2/14/61 21:00 0.315 13 3. 99 0.749
0.232 37 11/22/61 2:00 0.313 14 3.70 0.729
B-52
SE l 44'n Street --June 2007
0.230 40 12/15/62 2:00 0.313 15 3.44 0.709
0.262 26 12/31/63 23:00 0.306 16 3.22 0.690
0.235 36 12/21/64 4:00 0.300 17 3.03 0.670
0.236 35 1/05/66 16: 00 0. 2 98 18 2.85 0.650
0.355 7 11/13/66 19:00 0. 2 90 19 2. 7 0 0.630
0.386 6 8/24/68 16:00 0.280 20 2.56 0.610
0.217 43 12/03/68 16:00 0. 277 21 2.44 0.590
0.238 34 1/13/70 22:00 0. 272 22 2.32 0.570
0.227 41 12/05/70 9: 00 0.272 23 2.22 0.550
0.336 9 2/27 /72 7:00 0.264 24 2. 13 0.530
0. 214 46 1/13/73 2:00 0. 2 62 25 2.04 0.510
0.243 32 11/28/73 9: 00 0.262 26 1. 96 0. 4 90
0.324 10 12/26/74 23:00 0.258 27 1. 89 0.470
0.216 44 12/02/75 20:00 0.258 28 1. 82 0.450
0.258 28 8/26/77 2:00 0.249 29 1. 75 0.430
0.351 8 9/17/78 2:00 0.247 30 1. 70 0. 410
0.315 13 9/08/79 15:00 0.244 31 1. 64 0.390
0.298 18 12/14/79 21:00 0.243 32 1. 59 0.370
0.322 11 11/21/80 11: 00 0.239 33 1. 54 0.350
0.443 2 10/06/81 0:00 0.238 34 1. 49 0.330
0.320 12 10/28/82 16:00 0.236 35 1. 45 0.310
0.249 29 1/03/84 1:00 0.235 36 1. 41 0. 2 91
0.220 42 6/06/85 22:00 0.232 37 1. 37 0. 271
0.300 17 1/18/86 16: 00 0.231 38 1. 33 0.251
0. 391 5 10/26/86 0:00 0.230 39 1. 30 0.231
0.185 49 11/11/87 0:00 0.230 40 1.27 0. 211
0.239 33 8/21/89 17:00 0.227 41 1. 24 0 .191
0. 4 67 1 1/09/90 6:00 0.220 42 1.21 0 .171
0.434 3 11/24/90 8:00 0.217 43 1.18 0.151
0.244 31 1/27 /92 15:00 0.216 44 1.15 0.131
0.169 50 11/01/92 16: 00 0.214 45 1.12 0 .111
0.193 48 11/30/93 22:00 0.214 46 1.10 0.091
0.247 30 11/30/94 4:00 0.208 47 1. 08 0.071
0.313 15 2/08/96 10:00 0 .193 48 1. 05 0.051
0. 2 90 19 1/02/97 6:00 0.185 49 1. 03 0.031
0.313 14 10/04/97 15:00 0.169 50 1. 01 0 .011
Computed Peaks 0.508 100.00 0.990
Computed Peaks 0. 4 66 50.00 0.980
Computed Peaks 0.425 25.00 0. 960
Computed Peaks 0 .371 10.00 0.900
Computed Peaks 0.360 8. OD 0.875
Computed Peaks 0.329 5. DO 0.800
Computed Peaks 0.268 2.00 0.500
Computed Peaks 0 .227 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-130.tsf Mean= 0.015 StdDev-0.175
Project Location:Sea-Tac Skew= 0.324
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
1. 16 19 2/16/49 21:00 2. 64 1 89.50 0. 98 9
2.64 1 3/03/50 16:00 2. 63 2 32.13 0. 969
1. 47 9 2/09/51 14:00 2.28 3 19.58 0. 94 9
0. 811 38 1/30/52 8:00 2.05 4 14. 08 0. 929
0.694 43 3/24/53 15:00 1. 79 5 10.99 0. 909
0.990 23 12/19/53 19:00 1. 77 6 9.01 0.889
1.18 17 2/07/55 17:00 1. 57 7 7.64 0.869
1.22 16 12/20/55 17:00 1. 55 8 6.63 0.849
B-53
SE 14¢1' Street -June 2()07
1. 33 13 12/09/56 14:00 1. 4 7 9 5.86 0. 82 9
0. 967 25 12/25/57 16:00 1. 41 10 5.24 0.809
0.740 41 1/26/59 20:00 1. 35 11 4.75 0.789
1. 31 14 11/20/59 21: 00 1. 34 12 4.34 0. 7 69
0.894 34 2/14/61 21:00 1. 33 13 3.99 0. 74 9
0.697 42 11/22/61 2:00 1. 31 14 3.70 0.729
0.940 29 12/15/62 2:00 1. 26 15 3.44 0.709
0.961 26 12/31/63 23:00 1. 22 16 3.22 0.690
0.788 39 12/21/64 4:00 1.18 17 3.03 o. 670
0.892 35 1/05/66 16:00 1.17 18 2.85 0.650
1. 35 11 1/19/67 14:00 1.16 19 2.70 0.630
1. 16 20 8/24/68 16:00 1.16 20 2.56 0.610
0.869 36 12/03/68 16:00 1.11 21 2.44 0.590
0.908 30 1/13/70 22:00 1.11 22 2.32 0.570
0.943 28 12/06/70 8:00 0.990 23 2.22 0.550
1. 77 6 2/27 /72 7:00 0.984 24 2.13 0.530
0.778 40 1/13/73 2:00 0. 967 25 2.04 0.510
0.984 24 11/28/73 9:00 0. 961 26 1. 96 o. 4 90
1. 57 7 12/26/74 23:00 0.961 27 1. 89 0.470
0. 8 97 32 12/02/75 20:00 0. 943 28 1. 82 0.450
0.594 47 8/26/77 2:00 0. 940 29 1. 7 5 0.430
1.11 21 9/22/78 19: 00 0.908 30 1. 70 0.410
0.607 46 9/08/79 15:00 0.902 31 1. 64 0.390
1. 26 15 12/14/79 21: 00 0.897 32 1. 59 0.370
1.11 22 11/21/80 11:00 0.897 33 1. 54 0.350
2.05 4 10/06/81 15:00 0.894 34 1. 49 0.330
0.902 31 1/05/83 8:00 0. 8 92 35 1. 45 0.310
o. 961 27 1/03/84 1:00 0.869 36 1. 41 0.291
0.563 49 6/06/85 23:00 0.847 37 1. 37 0. 271
1. 55 8 1/18/86 16: 00 0. 811 38 1. 33 0.251
1. 41 10 11/24/86 3:00 0.788 39 1. 30 0.231
0.619 45 1/14/88 12:00 0.778 40 1.27 0. 211
0.567 48 11/05/88 14: 00 0.740 41 1. 24 0.191
2.63 2 1/09/90 6:00 0.697 42 1. 21 0 .171
2.28 3 11/24/90 8:00 0.694 43 1.18 0.151
0.897 33 1/27 /92 15:00 0.632 44 1.15 0.131
0.632 44 3/22/93 22:00 0.619 45 1. 12 0 .111
0. 413 50 11/30/93 22:00 0.607 46 1.10 0.091
0.847 37 12/27/94 1: 00 0.594 47 1. 08 0.071
1. 79 5 2/08/96 10:00 0.567 48 1. 05 0.051
1. 34 12 1/02/97 6:00 0.563 49 1. 03 0.031
1.17 18 10/04/97 15:00 0.413 50 1. 01 0. 011
Computed Peaks 2.90 100.00 0.990
Computed Peaks 2.53 50.00 0.980
Computed Peaks 2.18 25.00 0. 960
Computed Peaks 1. 75 10.00 0.900
Computed Peaks 1. 67 8.00 0.875
Computed Peaks 1. 44 5.00 0.800
Computed Peaks 1. 01 2.00 0.500
Computed Peaks 0.759 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-200.tsf Mean= -0.308 StdDev= 0 .145
Project Location:Sea-Tac Skew= 0.500
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0.561 18 2/16/49 21:00 1. 12 1 89.50 0.989
1. 09 2 3/03/50 16: 00 1. o 9 2 32.13 0. 969
B-54
SE 14.f' Srreet -June 2007
0.660 9 2/09/51 14:00 0.987 3 19.58 0.949
0.398 39 1/30/52 8:00 0.834 4 14. 08 0.929
0.358 43 3/24/53 15:00 D. 7 95 5 10.99 0.909
0.475 24 12/19/53 19:00 0.777 6 9.01 0.889
0.554 19 2/07/55 17:00 0.700 7 7.64 0.869
0.562 16 12/20/55 17:00 0.697 8 6.63 0.849
0.607 13 12/09/56 14: 00 0.660 9 5.86 0.829
0. 4 62 25 12/25/57 16:00 0.626 10 5.24 0.809
0.364 42 1/26/59 20:00 0.623 11 4.75 0.789
0.569 15 11/20/59 21:00 0.615 12 4.34 0.769
0.435 30 2/14/61 21:00 0.607 13 3. 99 0. 749
0.339 45 11/22/61 2:00 0.574 14 3.70 0.729
0.438 29 12/15/62 2:00 0.569 15 3.44 0.709
C.477 23 12/31/63 23:00 0.562 16 3.22 0.690
C.395 40 12/21/64 4:00 0.561 17 3.03 0.670
0.435 31 1/05/66 16:00 0.561 18 2.85 0.650
0.623 11 1/19/67 14: 00 0.554 19 2.70 0.630
0. 574 14 8/24/68 16:00 0.502 20 2.56 0.610
0. 421 36 12/03/68 16:00 0.500 21 2.44 0.590
0.434 32 1/13/70 22:00 0.494 22 2. 32 0.570
0.426 35 12/06/70 8:00 0.477 23 2.22 0.550
0.777 6 2/27 /72 7:00 0.475 24 2.13 0.530
0.388 41 1/13/73 2:00 0.462 25 2.04 0. 510
0.446 28 11/28/73 9:00 0.459 26 1. 96 0. 4 90
0.697 8 12/26/74 23: 00 0.457 27 1. 89 0.470
0.427 34 12/02/75 20:00 D. 44 6 28 1. 82 0.450
0. 34 6 44 8/26/77 2:00 0.438 29 1. 75 0.430
0.502 20 9/22/78 19:00 0.435 30 1. 70 0.410
0.401 38 9/08/79 15:00 0.435 31 1. 64 0.390
0. 561 17 12/14/79 21:00 0.434 32 1. 5 9 0.370
0. 4 94 22 11/21/80 11: 00 0. 4 32 33 1. 54 0.350
0.834 4 10/06/81 15:00 0.427 34 1. 49 0.330
0.457 27 10/28/82 16:00 0.426 35 1. 45 0.310
0.459 26 1/03/84 1:00 0.421 36 1. 41 D. 291
0.307 46 6/06/85 22:00 0.407 37 1. 37 0.271
0.700 7 1/18/86 16:00 0.401 38 1. 33 0.251
D. 626 10 11/24/86 3:00 0.398 39 1. 30 0.231
0.296 48 1/14/88 12:00 0.395 40 1. 27 0.211
0.283 49 8/21/89 17:00 0.388 41 1. 24 0.191
1.12 1 1/09/90 6:00 0.364 42 1. 21 0.171
0.987 3 11/24/90 8:00 0.358 43 1.18 0.151
0.432 33 1/27/92 15:00 0. 34 6 44 1.15 0.131
0.302 47 3/22/93 22 :00 0.339 45 1.12 0 .111
0.254 50 11/30/93 22:00 0.307 46 1.10 0.091
0.407 37 2/18/95 20:00 0.302 47 1. 08 0. 071
0. 7 95 5 2/08/96 10:00 0. 296 48 1. 05 0.051
0.615 12 1/02/97 6:00 0.283 49 1. 03 0.031
0.500 21 10/04/97 15:00 0.254 50 1. 01 0. 011
Computed Peaks 1. 21 100.00 0.990
Computed Peaks 1. 06 50.00 0.980
Computed Peaks 0.931 25. 00 0.960
Computed Peaks 0.766 10.00 0.900
Computed Peaks 0.733 8.00 0.875
Computed Peaks 0.645 5.00 0.800
Computed Peaks 0. 47 9 2. DO 0.500
Computed Peaks 0.380 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-210.tsf Mean= 0. 056 StdDev~ 0.136
Project Location:Sea-Tac Skew= 0.482
B-55
SE 14¢AStreet-June2007
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
1. 24 19 2/16/49 21:00 2.48 1 89.50 0.989
2.42 2 3/03/50 16:00 2.42 2 32.13 0.969
1. 40 11 2/09/51 2:00 2.20 3 19.58 0.949
0.884 40 1/30/52 8:00 1. 97 4 14. 08 0. 929
0.845 44 3/24/53 15:00 1. 72 5 10.99 0.909
1.10 25 12/19/53 19:00 1.66 6 9.01 0.889
1. 19 21 2/07/55 17:00 1. 56 7 7.64 0.869
1. 21 20 12/20/55 17:00 1. 49 8 6.63 0.849
1. 38 12 12/09/56 14:00 1. 4 6 9 5.86 0.829
1.11 24 12/25/57 16:00 1. 43 10 5.24 0.809
0.835 45 1/26/59 20:00 1. 40 11 4. 7 5 0.789
1.18 22 11/20/59 21:00 1. 38 12 4.34 0.769
0. 996 33 2/14/61 21:00 1. 37 13 3.99 0.749
0. 867 43 11/22/61 2:00 1. 37 14 3.70 0. 729
1. 01 30 12/15/62 2:00 1. 33 15 3.44 0.709
1. 09 26 12/31/63 23:00 1. 30 16 3.22 0.690
0.936 39 12/21/64 4:00 1. 30 17 3.03 0. 670
0.995 34 1/05/66 16:00 1.27 18 2.85 0.650
1.43 10 11/13/66 19:00 1. 24 19 2.70 0.630
1. 4 6 9 8/24/68 16:00 1. 21 20 2.56 0.610
0.937 38 12/03/68 16:00 1.19 21 2.44 0.590
1. 00 31 1/13/70 22: 00 1.18 22 2.32 0.570
0.989 35 12/06/70 8:00 1.16 23 2 .22 0.550
1. 72 5 2/27 /72 7:00 1.11 24 2.13 0.530
0. 87 6 41 1/13/73 2:00 1.10 25 2.04 0.510
1. 08 27 11/28/73 9:00 1. 0 9 26 1. 96 0. 4 90
1. 56 7 12/26/74 23:00 1. 08 27 1. 89 0.470
0.949 36 12/02/75 20:00 1. 0 6 28 1. 82 0.450
0.870 42 8/26/77 2:00 1. 02 29 1. 75 0.430
1. 30 16 9/22/78 19:00 1. 01 30 1. 70 0.410
0.999 32 9/08/79 15:00 1. 00 31 1. 64 0.390
1. 33 15 12/14/79 21: 00 0.999 32 1. 59 0.370
1.27 18 11/21/80 11: 00 0. 996 33 1. 54 0.350
1. 97 4 10/06/81 15:00 0.995 34 1. 49 0.330
1. 16 23 10/28/82 16: 00 0. 989 35 1. 45 0.310
1. 06 28 1/03/84 1:00 0. 94 9 36 1. 41 0. 2 91
0.775 46 6/06/85 22:00 0.937 37 1. 37 0. 271
1. 4 9 8 1/18/86 16: 00 0.937 38 1. 33 0.251
1. 37 13 10/26/86 0:00 0. 936 39 1. 30 0.231
0.656 48 1/14/88 12:00 0.884 40 1. 27 0. 211
0.712 47 11/05/88 14:00 0. 87 6 41 1. 24 0.191
2.48 1 1/09/90 6:00 0.870 42 1. 21 0 .171
2.20 3 11/24/90 8:00 0.867 43 1.18 0.151
1. 02 29 1/27/92 15:00 0.845 44 1.15 0.131
0. 643 49 3/22/93 22:00 0.835 45 1.12 0 .111
0. 63 6 50 11/30/93 22:00 0. 775 46 1.10 0.091
0.937 37 11/30/94 4:00 0. 712 47 1. 08 0. 071
1. 66 6 2/08/96 10:00 0.656 48 1. 05 0.051
1. 37 14 1/02/97 6:00 0.643 49 1. 03 0.031
1. 30 17 10/04/97 15:00 0.636 50 1. 01 0. 011
Computed Peaks 2.63 100.00 0.990
Computed Peaks 2.34 50.00 0.980
Computed Peaks 2.07 25.00 0.960
Computed Peaks 1. 72 10.00 0.900
Computed Peaks 1. 66 8.00 0.875
Computed Peaks 1. 47 5.00 0.800
B-56
SE 14¢h Street-June 2007
Computed Peaks 1.11 2.00 0.500
Computed Peaks 0. 8 93 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-220.tsf Mean= -0.235 StdDev= 0 .114
Project Location:Sea-Tac Skew~ 0.400
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0.601 21 2/16/49 21: 00 1. 09 1 8 9. 50 0.989
1. 04 2 3/03/50 16:00 1. 04 2 32 .13 0. 969
0.624 19 2/09/51 2:00 0. 989 3 19. 58 0. 94 9
0.466 40 10/15/51 13:00 0.955 4 14.08 0. 92 9
0.453 44 3/24/53 15:00 0.823 5 10.99 0. 909
0.557 26 12/19/53 19: 00 0. 811 6 9.01 0.889
0.571 23 11/25/54 2:00 0. 772 7 7.64 0.869
0.558 25 11/18/55 15:00 0. 7 65 8 6.63 0.849
0. 672 14 12/09/56 14:00 0. 723 9 5. 8 6 0.829
0.584 22 12/25/57 16: 00 0.713 10 5.24 0.809
0.432 47 11/18/58 13:00 0.702 11 4.75 0.789
0.567 24 11/20/59 5:00 0.688 12 4.34 0.769
0.501 36 2/14/61 21: 00 0.683 13 3.99 0.749
0.488 38 11/22/61 2:00 0. 672 14 3.70 0. 729
0.501 35 12/15/62 2:00 0.666 15 3.44 0.709
0.556 27 12/31/63 23:00 0.660 16 3.22 0.690
0.497 37 12/21/64 4:00 0.658 17 3.03 0. 670
0.503 34 1/05/66 16: 00 0. 641 18 2.85 0.650
0. 7 65 8 11/13/66 19:00 0.624 19 2. 70 0.630
0.823 5 8/24/68 16:00 0.622 20 2.56 0.610
0. 4 60 41 12/03/68 16:00 0.601 21 2. 44 0.590
0.508 33 1/13/70 22: 00 0.584 22 2. 32 0.570
0.487 39 12/06/70 8:00 o .571 23 2. 22 0.550
0. 772 7 2/27 /72 7:00 0.567 24 2.13 0.530
0.445 46 1/13/73 2:00 0.558 25 2.04 0.510
0.545 28 11/28/73 9:00 0.557 26 1. 96 0. 4 90
0.723 9 12/26/74 23:00 0.556 27 1.89 0.470
0. 4 60 42 12/02/75 20:00 0.545 28 1. 82 0.450
0.520 31 8/26/77 2:00 0.540 29 1.75 0.430
o. 713 10 9/17 /78 2:00 0. 524 30 1. 70 0.410
0.622 20 9/08/79 15:00 0.520 31 1. 64 0.390
0.658 17 12/14/79 21:00 0.518 32 1. 59 0.370
0.683 13 11/21/80 11: 00 0.508 33 1. 54 0.350
0.955 4 10/06/81 0:00 0.503 34 1. 4 9 0.330
0.666 15 10/28/82 16:00 0.501 35 1. 45 0.310
0.540 29 1/03/84 1:00 0.501 36 1. 41 0. 291
0.453 45 6/06/85 22:00 0.497 37 1. 37 0.271
0.660 16 1/18/86 16:00 0.488 38 1. 33 0.251
0. 811 6 10/26/86 0:00 0.487 39 1. 30 0.231
0.351 49 11/11/87 0:00 0.466 40 1. 27 0.211
0.455 43 8/21/89 17:00 0. 4 60 41 1. 24 0.191
1. 09 1 1/09/90 6:00 0. 4 60 42 1. 21 0 .171
0.989 3 11/24/90 8:00 0.455 43 1.18 0.151
0.524 30 1/27 /92 15:00 0. 453 44 1.15 0.131
0.330 50 11/01/92 16:00 0.453 45 1.12 0 .111
0.386 48 11/30/93 22 :00 0.445 46 1.10 0.091
0.518 32 11/30/94 4:00 0.432 47 1. 08 0.071
0.702 11 2/08/96 10:00 0.386 48 1. 05 0.051
0. 641 18 1/02/97 6:00 0.351 49 1. 03 0.031
0.688 12 10/04/97 15:00 0.330 50 1. 01 0.011
B-57
SE l 4(h Street-June 2007
Computed Peaks 1.16 100.00 0.990
Computed Peaks 1. 05 50.00 0.980
Computed Peaks 0.953 25.00 0. 960
Computed Peaks 0.822 10.00 0. 900
Computed Peaks 0. 7 95 8.00 0.875
Computed Peaks 0. 721 5.00 0.800
Computed Peaks 0.572 2.00 0.500
Computed Peaks 0.474 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-220rd.tsf Mean= -0.991 StdDev= 0.418
Project Location:Sea-Tac Skew= 0.698
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks --Rank Return Prob
(CFS) (CFS) (ft) Period
0.039 38 2/22/49 22:00 0.935 5.13 1 89.50 0.989
0 .110 19 3/05/50 6:00 0.681 5.10 2 32.13 0.969
0.489 6 2/09/51 15:00 0.575 5.08 3 19.58 0.949
0.035 43 2/04/52 8: 00 0.569 5.08 4 14. 08 0. 929
0.099 22 1/18/53 21:00 0.523 5.07 5 10.99 0.909
0.064 35 1/07/54 20:00 0.489 5. 0 6 6 9.01 0.889
0.040 36 2/08/55 22:00 0.483 5.06 7 7.64 0.869
0.159 12 1/06/56 10:00 0.478 5.06 8 6.63 0.849
0.067 34 2/26/57 4:00 0.389 5.04 9 5.86 0.829
0.100 21 1/17/58 7:00 0. 277 5.02 10 5.24 0.809
0.040 37 1/27/59 1:00 0 .160 4.87 11 4.75 0.789
0.478 8 11/20/59 21:00 0.159 4.86 12 4.34 0.769
0.134 16 11/24/60 10:00 0.152 4.82 13 3.99 0.749
0.035 46 12/24/61 6:00 0.141 4.77 14 3.70 0. 729
0.087 27 11/26/62 10:00 0 .138 4.75 15 3.44 0.709
0.100 20 11/19/63 16:00 0.134 4.73 16 3.22 0.690
0.138 15 11/30/64 14:00 0.120 4. 63 17 3.03 0.670
0.077 33 1/06/66 21:00 0 .114 4.58 18 2.85 0.650
0 .114 18 12/13/66 11 :00 0 .110 4.54 19 2.70 0.630
0.082 29 1/20/68 19:00 0.100 4. 41 20 2.56 0.610
0.080 30 12/11/68 6:00 0.100 4. 41 21 2.44 0.590
0.093 23 1/27 /70 2:00 0.099 4.38 22 2.32 0.570
0.087 28 12/07 /70 5:00 0.093 4.30 23 2.22 0.550
0.483 7 3/06/72 19:00 0.093 4. 2 9 24 2 .13 0.530
0.152 13 12/26/72 5:00 0. 092 4. 28 25 2.04 0.510
0. 0 90 26 1/16/74 18:00 0.090 4. 2 6 26 1. 96 0.490
0.039 39 1/14/75 2:00 0.087 4.22 27 1. 89 0.470
0.078 32 12/04/75 2:00 0.087 4.21 28 1. 82 0.450
0.031 49 8/26/77 8:00 0.082 4.15 29 1. 75 0.430
0.120 17 12/15/77 17:00 0.080 4 .13 30 1. 70 0.410
0. 032 48 2/13/79 1: 00 0.080 4.13 31 1. 64 0.390
0. 277 10 12/17 /79 17:00 0.078 4 .11 32 1. 59 0.370
0. 092 25 12/30/80 16:00 0.077 4.10 33 1. 54 0.350
0.681 2 10/06/81 16: 00 0. 067 4.02 34 1. 4 9 0.330
0.080 31 1/06/83 14:00 0.064 4.01 35 1. 45 0.310
0.035 45 12/10/83 21: 00 0.040 3.85 36 1. 41 0. 291
0.037 41 11/04/84 8:00 0.040 3.78 37 1. 37 0.271
0 .141 14 1/18/86 23:00 0.039 3.71 38 1. 33 0.251
0.569 4 11/24/86 4:00 0.039 3.67 39 1. 30 0.231
0.038 40 12/10/87 8:00 0.038 3. 4 9 40 1.27 0.211
0.035 44 11/05/88 23:00 0.037 3.16 41 1. 24 0 .191
0.935 1 1/09/90 8:00 0.037 3.13 42 1. 21 0.171
0. 523 5 11/24/90 11: 00 0.035 3.01 43 1.18 0.151
0.093 24 1/31/92 6:00 0.035 3.00 44 1.15 0.131
B-58
SE 14.f' Street-June 2007
0.034 47 1/26/93 5:00 0.035 2. 92 45 1.12 0 .111
0.030 50 2/17/94 23:00 0.035 2.90 46 1.10 0.091
0.160 11 12/27/94 6:00 0.034 2.75 47 1. 08 0. 071
0.575 3 2/08/96 11: 00 0.032 2.43 48 1. 05 0.051
0.389 9 1/02/97 10:00 0.031 2.31 49 1. 03 0.031
0.037 42 1/25/98 0: 00 0.030 2.22 50 1. 01 0. 011
Computed Peaks 1. 55 5.20 100.00 0.990
Computed Peaks 1.04 5.15 50.00 0.980
Computed Peaks 0.678 5.10 25.00 0. 960
Computed Peaks 0.368 5.04 10.00 0.900
Computed Peaks 0. 323 5.03 8.00 0.875
Computed Peaks 0. 219 5.01 5.00 0.800
Computed Peaks 0.091 4.27 2.00 0.500
Computed Peaks 0.048 3. 96 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-230.tsf Mean= 0.197 StdDev= 0.103
Project Location:Sea-Tac Skew= 0.461
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
1. 60 21 2/16/49 21:00 2.72 1 89.50 0. 989
2.49 4 3/03/50 16:00 2.57 2 32.13 0. 969
1. 64 20 2/09/51 2:00 2.53 3 19. 58 0. 94 9
1. 32 40 10/15/51 13:00 2.49 4 14.08 0. 92 9
1. 23 46 3/24/53 15:00 2.24 5 10.99 0. 909
1. 4 9 27 12/19/53 19:00 2.22 6 9.01 0.889
1. 5 7 22 11/25/54 2:00 2.05 7 7.64 0.869
1. 52 25 11/18/ 55 15:00 2.00 8 6.63 0. 84 9
1.77 16 12/09/56 14:00 1. 96 9 5. 8 6 0.829
1. 57 23 12/25/57 16:00 1. 88 10 5.24 0.809
1.21 47 11/18/58 13:00 1. 86 11 4.75 0.789
1. 54 24 11/20/ 59 5:00 1. 84 12 4.34 0. 7 69
1. 33 38 2/14/61 21:00 1. 83 13 3.99 0.749
1. 33 37 11 /22 / 61 2:00 1. 81 14 3.70 0. 729
1. 33 39 12/15/62 2:00 1. 80 15 3.44 0.709
1. 52 26 12/31/63 23:00 1. 77 16 3.22 0.690
1. 36 36 12/21/64 4:00 1. 75 17 3.03 0. 670
1. 37 34 1/05/66 16:00 1. 73 18 2.85 0.650
2.05 7 11/13/66 19:00 1. 68 19 2.70 0.630
2.22 6 8/24/68 16:00 1. 64 20 2.56 0.610
1. 26 42 12/03/68 16: 00 1. 60 21 2.44 0.590
1. 38 33 1/13/70 22:00 1. 57 22 2.32 0.570
1. 31 41 12/06/70 8:00 1. 57 23 2.22 0.550
1. 96 9 2/27 /72 7:00 1. 54 24 2.13 0.530
1. 24 45 1/13/73 2:00 1. 52 25 2.04 0.510
1. 40 32 11/28/73 9:00 1. 52 26 1. 96 0.490
1. 88 10 12/26/74 23:00 1.49 27 1. 89 0.470
1. 25 44 12/02/75 20:00 1. 4 7 28 1. 82 0.450
1. 4 7 28 8/26/77 2:00 1. 44 29 1. 75 0.430
2.00 8 9/17 /78 2:00 1. 42 30 1. 70 0.410
1. 80 15 9/08/79 15:00 1. 41 31 1. 64 0.390
1. 73 18 12/14/79 21:00 1. 40 32 1. 59 0.370
1. 86 11 11/21/80 11: 00 1. 38 33 1. 54 0.350
2.57 2 10/06/81 0:00 1. 37 34 1. 4 9 0.330
1. 84 12 10/28/82 16:00 1. 36 35 1. 45 0.310
1. 44 29 1/03/84 1: 00 1. 36 36 1. 41 0.291
1. 26 43 6/06/85 22:00 1. 33 37 1. 37 0.271
1. 7 5 17 1/18/86 16:00 1. 33 38 1. 33 0.251
B-59
SE 144'~ Street-June 2007
2.24 5 10/26/86 0:00 1. 33 39 1. 30 0.231
1. 05 49 11/11/87 0:00 1. 32 40 1. 27 0. 211
1. 36 35 8/21/89 17:00 1. 31 41 1. 24 0.191
2. 72 1 1/09/90 6:00 1. 26 42 1. 21 0.171
2.53 3 11/24/90 8:00 1. 2 6 43 1.18 0.151
1.41 31 1/27/92 15:00 1. 25 44 1.15 0.131
0.962 50 11/01/92 16: 00 1. 24 45 1. 12 0 .111
1.10 48 11/30/93 22:00 1. 23 46 1.10 0.091
1. 42 30 11/30/94 4: 00 1.21 47 1. 08 0. 071
1. 83 13 2/08/96 10:00 1. 10 48 1. 05 0.051
1. 68 19 1/02/97 6: 00 1. 05 49 1. 03 0.031
1. 81 14 10/04/97 15: OD 0.962 50 1.01 0. 011
Computed Peaks 2.95 100.00 0.990
Computed Peaks 2.70 50.00 0.980
Computed Peaks 2.46 25.00 0.960
Computed Peaks 2.15 10.00 0.900
Computed Peaks 2.09 8.00 0.875
Computed Peaks 1. 91 5.00 0.800
Computed Peaks 1. 55 2.00 0.500
Computed Peaks 1. 31 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-230rd.tsf Mean= -0.774 StdDev~ 0.235
Project Location:Sea-Tac Skew= 1. 289
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks --Rank Return Prob
(CFS) (CFS) (ft) Period
0 .118 39 2/22/49 6:00 0.559 7.00 1 89.50 0.989
0.141 17 3/05/50 11 :00 0.550 6. 95 2 32.13 0. 969
0.559 1 2/09/51 20:00 0.484 6.59 3 19.58 0.949
0.108 46 2/04/52 6:00 0.480 6.57 4 14.08 0. 929
0.130 29 1/23/53 8:00 0.479 6.56 5 10.99 0.909
0.130 30 1/06/54 12:00 0.478 6.56 6 9.01 0.889
0.129 32 2/08/55 8:00 0. 471 6.53 7 7.64 0.869
0.247 11 1/06/56 12:00 0.452 6.45 8 6.63 0.849
0.129 33 2/26/57 4:00 0.407 6 .27 9 5.86 0.829
0.136 20 1/17/58 8:00 0. 2 91 6.03 10 5.24 0.809
0 .119 38 1/24/59 16:00 0.247 5.94 11 4.75 0.789
0.478 6 11/21/59 3:00 0. 219 5. 7 6 12 4.34 0.769
0.142 15 11/24/60 17:00 0.218 5.75 13 3.99 0.749
0.104 48 12/24/61 6:00 0.176 5.62 14 3.70 0. 729
0.132 26 11/27 /62 5:00 0.142 5.42 15 3.44 0.709
0.136 21 11/19/63 18:00 0.142 5.40 16 3.22 0.690
0.218 13 12/01/64 8:00 0.141 5.33 17 3.03 0.670
0.125 37 1/07/66 3:00 0.140 5 .27 18 2.85 0.650
0 .136 22 12/15/66 8:00 0.138 5.16 19 2.70 0.630
0.127 34 1/20/68 21:00 0 .136 5.01 20 2.56 0.610
0.125 35 12/11/68 7:00 0.136 4. 96 21 2.44 0.590
0.132 27 1/27 /70 4:00 0.136 4. 96 22 2.32 0.570
0.134 25 12/07 /70 11: 00 0 .135 4.90 23 2.22 0.550
0.480 4 3/06/72 22:00 0.135 4.89 24 2.13 0.530
0.219 12 12/27 /72 18:00 0.134 4.83 25 2.04 0.510
0.135 23 1/16/74 19: 00 0 .132 4.68 26 1. 96 0.490
0.125 36 12/27 /74 10:00 0.132 4.68 27 1. 8 9 0.470
0.131 28 12/04/75 3:00 0.131 4.62 28 1. 82 0.450
0.105 47 8/26/77 7:00 0.130 4.54 29 1. 75 0.430
0.138 19 12/15/77 21: DO 0.130 4.54 30 1. 70 0.410
0.102 49 2/12/79 17:00 0.130 4.54 31 1. 64 0.390
0. 471 7 12/17/79 20:00 0.129 4.48 32 1. 59 0.370
B-60
SE 14,f' Street-June 2007
0.130 31 12/30/80 22:00 0.129 4.46 33 1. 54 0.350
0.291 10 10/06/81 19: 00 0.127 4.31 34 1. 49 0.330
0.135 24 1/08/83 3:00 0.125 4.18 35 1. 45 0.310
0 .111 44 12/10/83 19: 00 0.125 4.18 36 1. 41 0.291
0 .117 40 11/04/84 0:00 0.125 4 .17 37 1. 37 0.271
0.176 14 1/19/86 7:00 0 .119 3.78 38 1. 33 0.251
0.407 9 11/24/86 8:00 0 .118 3. 72 39 1. 30 0.231
0 .114 41 12/09/87 22:00 0 .117 3.68 40 1. 27 0. 211
0 .113 43 11/05/88 22:00 0 .114 3.53 41 1. 24 0 .191
0.484 3 1/09/90 14: 00 0 .113 3.46 42 1.21 0 .171
0.452 8 4/05/91 6: 00 0 .113 3.40 43 1.18 0.151
0.140 18 1/31/92 22:00 0 .111 3.33 44 1.15 0 .131
0.109 45 3/23/93 12:00 0.109 3.22 45 1.12 0 .111
0.098 50 2/17/94 21:00 0.108 3.15 46 1.10 0.091
0.142 16 12/27/94 20:00 0.105 2.98 47 1. 08 0. 071
0.550 2 2/09/96 4:00 0.104 2.94 48 1. 05 0.051
0.479 5 1/02/97 12:00 0.102 2.76 49 1. 03 0.031
0.113 42 10/30/97 11: 00 0.098 2.59 50 1. 01 0. 011
Computed Peaks 0.953 7.57 100.00 0.990
Computed Peaks 0. 711 7.51 50.00 0.980
Computed Peaks 0. 526 6.81 25.00 0. 960
Computed Peaks 0.347 6.09 10.00 0.900
Computed Peaks 0.320 6.07 8.00 0.875
Computed Peaks 0.249 5.94 5.00 0.800
Computed Peaks 0. 150 5.55 2.00 0.500
Computed Peaks 0 .111 3.30 1.30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-232.tsf Mean= -1.477 StdDev= 0.232
Project Location;Sea-Tac Skew~ -0.124
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Re-:.urn Prob
(CFS) (CFS) Period
0.041 16 2/16/49 22:00 0.093 1 89.50 0.989
0.080 5 3/03/50 16:00 0.088 2 32.13 0. 969
0.088 2 2/09/51 18:00 0.083 3 19.58 0.949
0.028 32 1/30/52 9:00 0.082 4 14. 08 0. 929
0. 021 42 1/18/53 19:00 0.080 5 10.99 0.909
0.031 27 1/06/54 5:00 0.068 6 9.01 0.889
0.054 10 2/07/55 21:00 0. 0 65 7 7.64 0.869
0. 04 6 13 12/20/55 17:00 0.059 8 6.63 0.849
0.036 21 12/09/56 15:00 0.055 9 5.86 0.829
0.038 20 1/16/58 20:00 0.054 10 5.24 0.809
0.032 24 1/24/59 2:00 0.054 11 4.75 0.789
0.059 8 11/20/59 21:00 0.047 12 4. 34 0.769
0.032 22 2/24/61 15:00 0.046 13 3.99 0. 749
0.019 44 1/03/62 1: 00 0.045 14 3.70 0. 72 9
0.026 36 11/25/62 14:00 0.042 15 3.44 0.709
0.032 25 1/01/64 18:00 0.041 16 3.22 0.690
0.022 39 11/30/64 12: 00 0.040 17 3.03 0.670
0.024 38 1/06/66 3:00 0.040 18 2.85 0.650
0.054 11 1/19/67 14:00 0.039 19 2.70 0.630
0.032 23 2/03/68 23:00 0.038 20 2.56 0.610
0.031 28 12/03/68 17:00 0.036 21 2.44 0.590
0.026 34 1/13/70 23:00 0.032 22 2.32 0.570
0.021 41 12/06/70 8:00 0.032 23 2.22 0.550
0.065 7 2/28/72 3:00 0.032 24 2.13 0.530
0. 02 9 30 1/13/73 5:00 0.032 25 2. 04 0.510
0.031 26 1/15/74 2:00 0. 031 26 1. 96 0. 4 90
B-61
SE 14¢1' Street-June 2007
0.047 12 12/26/74 23:00 0.031 27 1. 89 0.470
0. 02 9 29 12/03/75 17:00 0.031 28 1. 82 0.450
0.004 50 3/24/77 20:00 0.029 29 1. 75 0.430
0.025 37 12/10/77 17:00 0.029 30 1. 70 0.410
0.015 46 2/12/79 8:00 0.028 31 1. 64 0.390
0.040 17 12/15/79 8:00 0.028 32 1. 59 0.370
0.022 40 12 /2 6/ 80 4: 00 0.027 33 1.54 0.350
0.040 18 10/06/81 15:00 0.026 34 1. 49 0.330
0.039 19 1/05/83 8:00 0.026 35 1. 45 0.310
0. 02 6 35 1/24/84 11: 00 0. 02 6 36 1. 41 0.291
0.012 48 2/11/85 5:00 0.025 37 1. 37 0.271
0.068 6 1/18/86 21: 00 0.024 38 1. 33 0.251
0.055 9 11/24/86 4:00 0.022 39 1. 30 0.231
0. 021 43 1/14/88 13:00 0.022 40 1. 27 0. 211
0.013 47 4/05/89 16:00 0. 021 41 1. 24 0.191
0.093 1 1/09/90 9:00 0 .021 42 1.21 0.171
0.082 4 4/05/91 2:00 0.021 43 1.18 0.151
0.027 33 1/27/92 17:00 0.019 44 1.15 0.131
0.028 31 3/23/93 0:00 0.016 45 1.12 0 .111
0.008 49 3/03/94 4:00 0.015 46 1.10 0.091
0.042 15 2/19/95 20:00 0.013 47 1. 08 0 .071
0.083 3 2/09/96 1:00 0.012 48 1. 05 0.051
0.045 14 1/02/97 9:00 0.008 49 1. 03 0.031
0.016 45 1/07/98 9:00 0.004 50 1. 01 0.011
Computed Peaks 0 .110 100.00 0.990
Computed Peaks 0. 0 97 50.00 0.980
Computed Peaks 0.083 25.00 0. 960
Computed Peaks 0.066 10. 00 0.900
Computed Peaks 0. 0 62 8.00 0.875
Computed Peaks 0.053 5.00 0.800
Computed Peaks 0.034 2.00 0.500
Computed Peaks 0.022 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-240.tsf Mean= 0.137 StdDev-0 .114
Project Location:Sea-Tac Skew= 0.402
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
1. 42 21 2/16/49 21 :00 2.57 1 89.50 0.989
2.44 2 3/03/50 16:00 2. 44 2 32 .13 0. 969
1. 4 7 19 2/09/51 2:00 2.33 3 19.58 0.949
1. 10 40 10/15/51 13:00 2.25 4 14.08 0. 929
1. 07 44 3/24/53 15:00 1. 94 5 10.99 0.909
1. 31 25 12/19/53 19:00 1.91 6 9.01 0.889
1. 34 23 11/25/54 2: 00 1. 82 7 7.64 0.869
1. 31 26 11/18/55 15:00 1.80 8 6.63 0.849
1. 58 14 12/09/56 14:00 1.70 9 5.86 0.829
1. 38 22 12/25/57 16:00 1. 68 10 5.24 0.809
1. 02 47 11/18/58 13: 00 1.65 11 4.75 0.789
1. 33 24 11/20/59 5:00 1. 62 12 4.34 0.769
1.18 35 2/14/61 21:00 1. 61 13 3. 99 0.749
1.15 38 11/22/61 2:00 1. 58 14 3.70 0. 729
1.18 36 12/15/62 2:00 1. 57 15 3.44 0.709
1. 31 27 12/31/63 23:00 1. 55 16 3.22 0.690
1.17 37 12/21/64 4:00 1. 55 17 3.03 0. 670
1.18 34 1/05/66 16:00 1. 51 18 2.85 0.650
1. 80 8 11/13/66 19:00 1. 4 7 19 2.70 0.630
1. 94 5 8/24/68 16:00 1. 4 6 20 2.56 0.610
B-62
SE I 44'~ Street -June 2007
1. 08 41 12/03/68 16: 00 1. 42 21 2.44 0.590
1. 20 33 1/13/70 22:00 1. 38 22 2.32 0.570
1.15 39 12/06/70 8:00 1. 34 23 2.22 0.550
1. 82 7 2/27 /72 7:00 1. 33 24 2.13 0.530
1. 05 46 1/13/73 2:00 1. 31 25 2.04 0.510
1. 28 28 11/28/73 9:00 1. 31 26 1. 96 0.490
1. 70 9 12/26/74 23:00 1. 31 27 1. 89 0.470
1. 08 42 12/02/75 20:00 1.28 28 1. 82 0.450
1. 23 31 8/26/77 2:00 1. 27 29 1. 75 0.430
1. 68 10 9/17/78 2:00 1. 23 30 1. 70 0.410
1. 46 20 9/08/79 15:00 1. 23 31 1. 64 0.390
1. 55 17 12/14/79 21: 00 1. 22 32 1. 59 0.370
1. 61 13 11/21/80 11: 00 1. 20 33 1. 54 0.350
2.25 4 10/06/81 0:00 1.18 34 1. 49 0.330
1. 57 15 10/28/82 16:00 1. 18 35 1. 45 0.310
1.27 29 1/03/84 1:00 1.18 36 1. 41 0. 2 91
1. 07 45 6/06/85 22:00 1.17 37 1. 37 0.271
1. 55 16 1/18/86 16:00 1.15 38 1. 33 0.251
1. 91 6 10/26/86 0:00 1.15 39 1. 30 0.231
0.828 49 11/11/87 0:00 1.10 40 1.27 0. 211
1. 07 43 8/21/89 17:00 1. 08 41 1. 24 0.191
2.57 1 1/09/90 6:00 1. 08 42 1.21 0. 171
2.33 3 11/24/90 8:00 1. 07 43 1.18 0.151
1. 23 30 1/27/92 15:00 1. 07 44 1.15 0 .131
0.778 50 11/01/92 16:00 1. 07 45 1.12 0 .111
0. 911 48 11/30/93 22:00 1. 05 46 1.10 0.091
1. 22 32 11/30/94 4:00 1. 02 47 1. 08 0 .071
1. 65 11 2/08/96 10:00 0. 911 48 1. 05 0.051
1. 51 18 1/02/97 6:00 0.828 49 1. 03 0.031
1. 62 12 10/04/97 15:00 0.778 50 1.01 0. 011
Computed Peaks 2.72 100.00 0.990
Computed Peaks 2.48 50.00 0.980
Computed Peaks 2.24 25.00 0. 960
Computed Peaks 1. 94 10.00 0.900
Computed Peaks 1. 87 8.00 0.875
Computed Peaks 1. 70 5.00 0.800
Computed Peaks 1. 35 2.00 0.500
Computed Peaks 1.12 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-24Drd.tsf Mean= -0.255 StdDev= 0.169
Project Location:Sea-Tac Skew= 1.275
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks --Rank Return Prob
(CFS) (CFS) (ft) Period
0. 471 30 2/17/49 1: OD 1. 34 4.97 1 89.50 0.989
0.524 18 3/04/50 4:00 1. 26 4.89 2 32.13 0. 969
1. 34 1 2/09/51 19:00 1. 26 4.89 3 19. 58 0. 94 9
0.416 44 1/30/52 11: OD 1. 21 4. 7 9 4 14.08 0. 929
0.432 40 9/30/53 17:00 1.21 4. 7 9 5 10.99 0. 909
0.484 25 1/06/54 7: 00 1.16 4. 63 6 9.01 0.889
0.570 11 2/08/55 0:00 1.15 4. 61 7 7.64 0.869
0.533 16 12/22/55 15:00 1. 08 4.43 8 6.63 0. 84 9
0.512 19 12/09/56 18:00 0.998 4.20 9 5.86 0.829
0.487 24 1/16/58 23:00 0. 943 4.08 10 5.24 0.809
0.459 32 10/19/58 9:00 0.570 3.66 11 4.75 0.789
1. 15 7 11/20/59 23:00 0.565 3.61 12 4.34 0.769
0. 4 90 23 11/20/60 16:00 0.553 3.46 13 3.99 0.749
0.382 47 1/03/62 3:00 0.543 3.34 14 3.70 0.729
B-63
SE 14..f' Street-June 2007
0.483 27 11/25/62 16:00 0.535 3.24 15 3. 44 0.709
0.473 28 1/01/64 20:00 0.533 3.22 16 3.22 0.690
0.499 21 11/24/64 10:00 0.528 3.16 17 3.03 0.670
0.421 43 12/28/65 17:00 0.524 3.11 18 2.85 0.650
0.543 14 1/19/67 19:00 0.512 2. 96 19 2. 70 0.630
0.442 38 2/19/68 4: 00 0.508 2. 92 20 2.56 0.610
0. 471 29 12/03/68 22:00 0. 4 99 2. 82 21 2. 44 0.590
0. 4 69 31 1/14/70 14:00 0.497 2. 80 22 2.32 0.570
0.508 20 12/06/70 14:00 0.490 2.73 23 2.22 0.550
0.998 9 2/28/72 7:00 0.487 2.69 24 2.13 0.530
0.440 39 12/26/72 6:00 0.484 2. 65 25 2.04 0.510
0.448 36 1/15/74 8:00 0.483 2. 65 26 1. 96 0. 4 90
0.553 13 12/27/74 6:00 0.483 2. 64 27 1. 89 0.470
0. 4 97 22 12/04/75 1:00 0.473 2.53 28 1. 82 0.450
0.359 49 8/24/77 0:00 0.471 2.51 29 1. 75 0.430
0.483 26 9/23/78 11: 00 0. 471 2.51 30 1. 70 0.410
0.387 46 11/19/78 8:00 0.469 2.48 31 1. 64 0. 390
0.943 10 12/15/79 9:00 0.459 2.38 32 1. 59 0.370
0. 42 6 42 11/21/80 14:00 0.457 2.36 33 l. 54 0.350
1. 2 6 3 10/06/81 17:00 0.455 2. 34 34 1. 49 0.330
0.528 17 1/05/83 15:00 0.450 2.30 35 1. 45 0.310
0.409 45 1/24/84 13:00 0.448 2.28 36 1. 41 0.291
0.455 34 6/07/85 7:00 0.444 2.24 37 1. 37 0. 271
1. 08 8 1/18/86 22:00 0.442 2 .21 38 1. 33 0.251
1. 16 6 11/24/86 7:00 0.440 2.20 39 1. 30 0.231
0.427 41 1/14/88 19:00 0.432 2 .11 40 1. 27 0. 211
0.368 48 11/05/88 19:00 0. 427 2.06 41 1. 24 0 .191
1. 2 6 2 1/09/90 11: 00 0. 42 6 2.05 42 1. 21 0 .171
1.21 4 4/05/91 3:00 0. 421 2.01 43 1.18 0.151
0.444 37 1/28/92 10:00 0.416 1. 96 44 1.15 0.131
0.450 35 3/23/93 5:00 0.409 1. 89 45 1.12 0 .111
0.333 50 12/01/93 16:00 0.387 1. 70 46 1.10 0.091
0.535 15 2/19/95 22:00 0.382 1. 66 47 1. 08 0.071
1. 21 5 2/09/96 3:00 0.368 1. 53 48 1. 05 0.051
0.565 12 1/02/97 12:00 0.359 1. 46 49 1. 03 0.031
0.457 33 10/30/97 9:00 0.333 1. 26 50 1. 01 0. 011
Computed Peaks 1. 93 5.23 100.00 0.990
Computed Peaks 1. 56 5.10 50.00 0. 980
Computed Peaks 1. 26 4.89 25.00 0. 960
Computed Peaks 0.935 4. 07 10.00 0. 900
Computed Peaks 0.881 3.99 8. 00 0.875
Computed Peaks 0.736 3. 8 9 5.00 0.800
Computed Peaks 0.512 2.97 2. 00 0.500
Computed Peaks 0. 411 1. 91 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-241.tsf Mean= 0.052 StdDev-0 .114
Project Location:Sea-Tac Skew= 0.403
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
1.17 21 2/16/49 21:00 2.12 1 89.50 0.989
2.02 2 3/03/50 16:00 2.02 2 32.13 0.969
1. 21 19 2/09/51 2:00 1. 93 3 19.58 0.949
0.902 40 10/15/51 13:00 1. 85 4 14.08 0. 92 9
0.879 44 3/24/53 15:00 1. 59 5 10.99 0.909
1. 08 25 12/19/53 19:00 1. 57 6 9.01 0.889
1.11 23 11/25/54 2:00 1. 50 7 7.64 0.869
1. 08 26 11/18/55 15:00 1. 48 8 6.63 0. 84 9
B-64
SE 14.f' Street-June 2007
1. 30 14 12/09/56 14:00 1. 40 9 5.86 0.829
1.13 22 12/25/57 16:00 1. 38 10 5.24 0.809
0.838 47 11/18/58 13:00 1. 37 11 4.75 0.789
1.10 24 11/20/59 5: 00 1. 33 12 4. 34 0.769
0. 972 36 2/14/61 21:00 1.32 13 3.99 0.749
0. 943 39 11/22/61 2:00 1. 30 14 3.70 0.729
0. 97 3 35 12/15/62 2:00 1. 29 15 3.44 0.709
1. 08 27 12/31/63 23:00 1. 29 16 3.22 0.690
0. 964 37 12/21/64 4: 00 1. 27 17 3.03 0.670
a. 97 6 34 1/05/66 16:00 1. 24 18 2.85 0.650
1. 48 8 11/13/66 19:00 1.21 19 2.70 0.630
1. 59 5 8/24/68 16:00 1. 20 20 2.56 0.610
0.893 42 12/03/68 16:00 1.1 7 21 2.44 0.590
0.985 33 1/13/70 22:00 1.13 22 2. 32 0.570
0.945 38 12/06/70 8: 00 1.11 23 2.22 0.550
1. 50 7 2/27 /72 7:00 1.10 24 2.13 0.530
0. 8 64 46 1/13/73 2:00 1. 08 25 2.04 0.510
1. 0 6 28 11/28/73 9:00 1. 08 26 1. 96 0.490
1. 40 9 12/26/74 23:00 1. 08 27 1. 89 0.470
0. 8 94 41 12/02/75 20:00 1. 06 28 1. 82 0.450
1. 01 31 8/26/77 2: 00 1. 05 29 1. 75 0.430
1. 38 10 9/17/78 2: 00 1. 02 30 1. 70 0.410
1. 20 20 9/08/79 15:00 1. 01 31 1. 64 0.390
1.27 17 12/14/79 21:00 1. 00 32 1. 59 0.370
1. 32 13 11/21/80 11: 00 C.985 33 1. 54 0.350
1. 85 4 10/06/81 0:00 0.976 34 1. 4 9 0.330
1. 29 15 10/28/82 16:00 0.973 35 1. 45 0.310
1. 05 29 1/03/84 1:00 0.972 36 1. 41 0.291
0.877 45 6/06/85 22:00 0. 964 37 1. 37 0. 271
1. 29 16 1/18/86 16:00 0.945 38 1. 33 0.251
1. 57 6 10/26/86 0:00 0.943 39 1. 30 0.231
0.680 49 11/11/87 0:00 0.902 40 1. 27 0. 211
0.881 43 8/21/89 17:00 0.894 41 1. 24 0.191
2.12 1 1/09/90 6:00 0.893 42 1. 21 0 .171
1. 93 3 11/24/90 8: 00 0.881 43 1.18 0.151
l. 02 30 1/27 /92 15:00 0.879 44 1.15 0 .131
0. 639 50 11/01/92 16:00 0. 877 45 1.12 0 .111
0.748 48 11/30/93 22:00 0.864 46 1.10 0.091
1. 00 32 11/30/94 4:00 0.838 47 1. 08 0. 071
1. 37 11 2/08/96 10:00 0.748 48 1. 05 0.051
1. 24 18 1/02/97 6:00 0.680 49 1. 03 0.031
1. 33 12 10/04/97 15:00 0.639 50 1. 01 0. 011
Computed Peaks 2.25 100.00 0. 990
Computed Peaks 2.05 50.00 0.980
Computed Peaks 1. 85 25.00 0. 960
Computed Peaks 1. 60 10.00 0.900
Computed Peaks 1. 54 8.00 0.875
Computed Peaks 1. 40 5.00 0.800
Computed Peaks 1.11 2. 00 0.500
Computed Peaks 0. 920 1. 30 0.231
Flow Frequency Analysis Log Pearson III Coefficients
Time Series File:c-244.tsf Mean= 0.350 StdDev~ 0.151
Project Location:Sea-Tac Skew= 0.463
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
2.43 21 2/16/49 21:00 5 .19 1 89.50 0.989
5.15 2 3/03/50 16:00 5.15 2 32.13 0.969
B-65
SE l 44'h Street-June 2007
2.87 10 2/09/51 2:00 4.57 3 19.58 0. 94 9
1. 72 39 1/30/52 8: 00 4.21 4 14.08 0. 929
1. 58 44 3/24/53 15: 00 3.54 5 10.99 0.909
2.15 25 12/19/53 19:00 3. 44 6 9.01 0.889
2.38 22 2/07/55 17:00 3 .19 7 7.64 0.869
2.45 20 12/20/55 17:00 3.06 8 6.63 0.849
2. 78 12 12/09/56 14: 00 2.89 9 5. 86 0.829
2.16 24 12/25/57 16:00 2.87 10 5.24 0.809
1. 61 43 1/26/59 20:00 2.82 11 4.75 0.789
2.49 19 11/20/59 21:00 2.78 12 4.34 0.769
1. 93 33 2/14/61 21:00 2.76 13 3. 99 0. 749
1. 65 42 11/22/61 2:00 2.74 14 3.70 0.729
2.00 29 12/15/62 2:00 2.68 15 3.44 0.709
2.10 27 12/31/63 23:00 2.63 16 3.22 0.690
1. 78 38 12/21/64 4:00 2.57 17 3.03 0.670
1. 93 34 1/05/66 16: 00 2.53 18 2.85 0.650
2.89 9 11/13/66 19: 00 2.49 19 2.70 0.630
2.76 13 8/24/68 16: 00 2.45 20 2.56 0.610
1. 83 36 12/03/68 16: 00 2.43 21 2.44 0.590
1. 96 32 1/13/70 22:00 2.38 22 2.32 0.570
2.00 30 12/06/70 8:00 2.18 23 2.22 0.550
3.54 5 2/27 /72 7:00 2 .16 24 2.13 0.530
1. 68 40 1/13/73 2:00 2.15 25 2.04 0.510
2.14 26 11/28/73 9:00 2 .14 26 1. 96 0.490
3.19 7 12/26/74 23:00 2.10 27 1. 89 0.470
1. 87 35 12/02/75 20:00 2. 08 28 1. 82 0.450
1. 53 45 8/26/77 2:00 2.00 29 1. 75 0.430
2.57 17 9/22/78 19: 00 2.00 30 1. 70 0.410
1. 67 41 9/08/79 15:00 1. 97 31 1. 64 0.390
2. 68 15 12/14/79 21:00 1. 96 32 1. 59 0.370
2.53 18 11/21/80 11 :00 1. 93 33 1. 54 0.350
4.21 4 10/06/81 15:00 1. 93 34 1. 49 0.330
2.18 23 10/28/82 16:00 1. 87 35 1.45 0.310
2.08 28 1/03/84 1: 00 1. 83 36 1. 41 0.291
1. 40 46 6/06/85 22:00 1. 79 37 1. 37 0. 271
3. 0 6 8 1/18/86 16:00 1.78 38 1. 33 0.251
2. 82 11 11/24/86 3: 00 1. 72 39 1. 30 0.231
1. 30 48 1/14/88 12:00 1. 68 40 1.27 0. 211
1. 36 47 11/05/88 14: 00 1. 67 41 1. 24 0 .191
5.19 1 1/09/90 6:00 1. 65 42 1. 21 0.171
4.57 3 11/24/90 8:00 1. 61 43 1.18 0.151
1. 97 31 1/27/92 15:00 1. 58 44 1.15 0.131
1. 28 49 3/22/93 22:00 1. 53 45 1.12 0 .111
1. 09 50 11/30/93 22:00 1. 40 46 1.10 0.091
1. 79 37 11/30/94 4: 00 1. 36 47 1. 08 0. 071
3.44 6 2/08/96 10:00 1. 30 48 1. 05 0.051
2.74 14 1/02/97 6:00 1. 28 49 1. 03 0.031
2. 63 16 10/04/97 15: 00 1. 09 50 1. 01 0. 011
Computed Peaks 5. 65 100.00 0. 990
Computed Peaks 4. 97 50.00 0.980
Computed Peaks 4.33 25.00 0. 960
Computed Peaks 3.54 10.00 0.900
Computed Peaks 3.39 8. 00 0.875
Computed Peaks 2. 97 5.00 0.800
Computed Peaks 2.18 2.00 0.500
Computed Peaks 1. 71 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-250.tsf Mean= 0.048 StdDev= 0.126
Project Location:Sea-Tac Skew= 0.396
B-66
SE 144'h Street-June 2007
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
1.18 20 2/16/49 21:00 2.27 1 89.50 0.989
2 .21 2 3/03/50 16:00 2.21 2 32.13 0.969
1. 27 18 2/09/51 2:00 2.02 3 19.58 0.949
0.844 44 10/15/51 13:00 1. 88 4 14.08 0. 929
0.855 42 3/24/53 15:00 1.58 5 10.99 0.909
1. 08 26 12/19/53 19:00 1. 55 6 9.01 0.889
1. 09 25 11/25/54 2:00 1. 48 7 7.64 0.869
1.10 23 12/20/55 17:00 1. 48 8 6.63 0.849
1. 33 14 12/09/56 14:00 1.46 9 5.86 0.829
1.12 21 12/25/57 16:00 1. 45 10 5.24 0.809
0. 817 46 1/26/59 20:00 1.35 11 4. 7 5 0.789
1.11 22 11/20/59 5:00 1. 34 12 4.34 0.769
0. 972 33 2/14/61 21:00 1.33 13 3.99 0.749
0.912 39 11/22/61 2:00 1. 33 14 3.70 0. 729
0.982 31 12/15/62 2: 00 1. 30 15 3.44 0.709
1. 06 28 12/31/63 23:00 1. 30 16 3.22 0.690
0. 941 37 12/21/64 4:00 1. 28 17 3.03 0.670
0. 967 35 1/05/66 16:00 1. 27 18 2.85 0.650
1. 4 8 8 11/13/66 19:00 1. 23 19 2.70 0.630
1. 55 6 8/24/68 16:00 1.18 20 2.56 0.610
0.889 41 12/03/68 16:00 1.12 21 2.44 0.590
0. 97 9 32 1 /13/70 22:00 1.11 22 2.32 0.570
0.954 36 12/06/70 8:00 1.10 23 2.22 0.550
1. 58 5 2/27 /72 7: 00 1. 09 24 2.13 0.530
0.845 43 1/13/73 2:00 1. 09 25 2.04 0.510
1. 08 27 11/28/73 9:00 1. 08 26 1. 96 0. 4 90
1. 46 9 12/26/74 23:00 1. 08 27 1. 8 9 0.470
0. 895 40 12/02/75 20:00 1. 06 28 1. 82 0.450
0. 936 38 8/26/77 2:00 1. 05 29 1. 75 0.430
1. 35 11 9/22/78 19:00 1. 01 30 1. 70 0.410
1. 09 24 9/08/79 15:00 0.982 31 1. 64 0.390
1. 30 16 12/14/79 21:00 0.979 32 1. 59 0.370
1. 30 15 11/21/80 11: 00 0. 972 33 1. 54 0.350
1. 88 4 10/06/81 15:00 0. 972 34 1. 4 9 0.330
1. 23 19 10/28/82 16:00 0.967 35 1. 45 0.310
1. 05 29 1/03/84 1:00 0.954 36 1. 41 0. 291
0.828 45 6/06/85 22:00 0.941 37 1. 37 0. 271
1. 33 13 1/18/86 16:00 0.936 38 1. 33 0.251
1. 48 7 10/26/86 0:00 0.912 39 1. 30 0.231
0.646 49 1/14/88 0:00 0.895 40 1.27 0. 211
0. 774 47 8/21/89 17:00 0.889 41 1. 24 0 .191
2.27 1 1/09/90 6:00 0.855 42 1. 21 0 .171
2.02 3 11/24/90 8:00 0.845 43 1.18 0.151
1. 01 30 1/27 /92 15:00 0.844 44 1.15 0.131
0.600 50 12/10/92 6:00 0.828 45 1.12 0 .111
0.689 48 11/30/93 22:00 0.817 46 1.10 0. 091
0.972 34 11/30/94 4:00 0.774 47 1. 08 0.071
1. 45 10 2/08/96 10:00 0.689 48 1. 05 0.051
1. 28 17 1/02/97 6:00 0.646 49 1. 03 0.031
1. 34 12 10/04/97 15:00 0.600 50 1. 01 0. 011
Computed Peaks 2.39 100.00 0.990
Computed Peaks 2.16 50.00 0.980
Computed Peaks 1. 93 25.00 0.960
Computed Peaks 1. 64 10.00 0.900
Computed Peaks 1. 58 8.00 0.875
Computed Peaks 1. 42 5.00 0.800
B-67
SE 14¢1' Street -June 2007
Computed Peaks 1.10 2.00 0.500
Computed Peaks 0.893 1. 30 0.231
Flow Frequency Analysis Log Pearson III Coefficients
Time Series File:c-260.tsf Mean= -0.230 StdDev= 0.124
Project Location:Sea-Tac Skew~ 0.395
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0.617 20 2/16/49 21:00 1.18 1 89.50 0.989
1.14 2 3/03/50 16:00 1.14 2 32.13 0. 969
0.660 18 2/09/51 2:00 1. 05 3 19.58 0.949
0.449 43 10/15/51 13:00 0. 977 4 14.08 0. 929
0.452 42 3/24/53 15:00 0.824 5 10.99 0. 909
0.567 26 12/19/53 19:00 0.819 6 9.01 0.889
0. 572 25 11/25/54 2:00 0.788 7 7.64 0.869
0.574 24 12/20/55 17:00 0.777 8 6.63 0. 84 9
0.695 13 12/09/56 14:00 0. 7 60 9 5. 8 6 0. 82 9
0.590 21 12/25/57 16: 00 0.752 10 5.24 0.809
0.430 46 11/18/58 13:00 0. 711 11 4.75 0.789
0.581 23 11/20/59 5:00 0.704 12 4.34 0. 7 69
0. 511 34 2/14/61 21:00 0.695 13 3.99 0. 74 9
0.483 39 11/22/61 2:00 0.695 14 3.70 0. 729
0.515 31 12/15/62 2:00 0.687 15 3.44 0.709
0.561 28 12/31/63 23:00 0.681 16 3.22 0.690
0.497 38 12/21/64 4:00 0.668 17 3.03 0.670
0.509 35 1/05/66 16:00 0.660 18 2.85 0.650
0. 777 8 11/13/66 19: 00 0.655 19 2. 70 0.630
0.819 6 8/24/68 16: 00 0.617 20 2.56 0.610
0.467 41 12/03/68 16:00 0.590 21 2.44 0.590
0.515 32 1/13/70 22:00 0.584 22 2.32 0.570
0.500 36 12/06/70 8:00 0.581 23 2.22 0.550
0.824 5 2/27/72 7:00 0.574 24 2.13 0.530
0.445 44 1/13/73 2:00 0 .572 25 2.04 0.510
0.564 27 11/28/73 9:00 0. 567 26 1. 96 0. 4 90
0.760 9 12/26/74 23:00 0. 564 27 1. 8 9 0.470
0.470 40 12/02/75 20:00 0.561 28 1. 82 0.450
0.499 37 8/26/77 2:00 0.550 29 1. 7 5 0.430
0. 711 11 9/22/78 19: 00 0.531 30 1. 70 0.410
0.584 22 9/08/79 15:00 0.515 31 1. 64 0.390
0.681 16 12/14/79 21:00 0.515 32 1. 59 0.370
0.687 15 11/21/80 11: 00 0.514 33 1. 54 0.350
0.977 4 10/06/81 15:00 0. 511 34 1. 49 0.330
0.655 19 10/28/82 16: 00 0.509 35 1. 45 0.310
0.550 29 1/03/84 1:00 0.500 36 1. 41 0.291
0.440 45 6/06/85 22:00 0.499 37 1. 37 0. 271
0.695 14 1/18/86 16:00 0.497 38 1. 33 0.251
0.788 7 10/26/86 0:00 0.483 39 1. 30 0.231
0.343 49 1/14/88 0:00 0.470 40 1. 27 0.211
0. 417 47 8/21/89 17:00 0.467 41 1. 24 0 .191
1. 18 1 1/09/90 6:00 0.452 42 1.21 0.171
1. 05 3 11/24/90 8:00 0.449 43 1. 18 0.151
0.531 30 1/27/92 15:00 0.445 44 1. 15 0.131
0.318 50 12/10/92 6:00 0.440 45 1.12 0 .111
0.368 48 11/30/93 22:00 0.430 46 1.10 0. 091
0.514 33 11/30/94 4:00 0.417 47 1. 08 0.071
0.752 10 2/08/96 10:00 0.368 48 1. 05 0.051
0.668 17 1/02/97 6:00 0.343 49 1. 03 0.031
0.704 12 10/04/97 15:00 0.318 50 1. 01 0. 011
B-68
SE J 44'h Street -June 2007
Computed Peaks 1. 24 100.00 0.990
Computed Peaks 1.12 50.00 0.980
Computed Peaks 1. 01 25.00 0.960
Computed Peaks 0.857 10.00 0.900
Computed Peaks 0.827 8.00 0.875
Computed Peaks 0.743 5.00 0.800
Computed Peaks 0. 577 2.00 0.500
Computed Peaks 0.472 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-260rd.tsf Mean= -0.785 StdDev~ 0. 2 91
Project Location:Sea-Tac Skew= 1. 218
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks --Rank Return Prob
(CFS) (CFS) (ft) Period
0.133 36 2/22/49 6:00 1.19 5.21 1 8 9. 50 0.989
0 .179 14 3/05/50 7:00 0.942 5.17 2 32.13 0. 969
0.942 2 2/09/51 16:00 0.932 5.17 3 19.58 0. 94 9
0.081 42 2/04/52 9:00 0. 577 5.11 4 14.08 0. 92 9
0 .152 25 1/12/53 7:00 0.543 5.10 5 10.99 0. 909
0.145 31 1/06/54 12:00 0.439 5.07 6 9.01 0.889
0.135 35 2/08/55 15:00 0.303 5.03 7 7.64 0.869
0.191 11 12/22/55 16: 00 0.225 5.00 8 6.63 0. 84 9
0.142 33 2/26/57 4:00 0.209 4.99 9 5.86 0.829
0.171 18 1/17/58 8:00 0.200 4.74 10 5.24 0.809
0.125 39 1/24/59 18:00 0 .191 4.51 11 4.75 0.789
0. 577 4 11/21/59 2:00 0.183 4.32 12 4.34 0.769
0.168 19 11/24/60 17:00 0.181 4.29 13 3.99 0. 749
0. 072 45 12/24/61 6:00 0.179 4.22 14 3.70 0.729
0.156 22 11/26/62 11: 00 0.178 4.21 15 3.44 0.709
0.152 26 11/19/63 18:00 0 .173 4 .11 16 3.22 0.690
0.183 12 12/01/64 8: 00 0 .172 4.08 17 3.03 0.670
0 .140 34 1/07/66 3:00 0.171 4.07 18 2.85 0.650
0 .172 17 12/13/66 15:00 0.168 4.00 19 2. 7 0 0.630
0.150 27 1/20/68 20:00 0. 162 3.89 20 2.56 0.610
0.133 37 12/11/68 7:00 0 .162 3.87 21 2.44 0.590
0.145 32 1/27 /70 4: 00 0.156 3.77 22 2.32 0.570
0.153 24 12/07 /70 11: 00 0.155 3.74 23 2. 22 0.550
0.209 9 3/07 /72 1:00 0.153 3.71 24 2 .13 0.530
0.173 16 12/27 /72 19:00 0.152 3.69 25 2.04 0.510
0.155 23 1/16/74 19:00 0.152 3. 68 26 1. 96 0.490
0 .127 38 1/13/75 23:00 0.150 3.65 27 1. 89 0.470
0.150 28 12/04/75 4: 00 0.150 3.65 28 1. 82 0.450
0.061 50 8/26/77 7:00 0 .14 7 3.59 29 1. 75 0.430
0 .162 20 12/15/77 19:00 0.146 3.57 30 1. 70 0.410
0.066 48 2/13/79 12:00 0 .145 3.56 31 1. 64 0.390
0.543 5 12/17/79 18:00 0.145 3.56 32 1. 59 0.370
0.147 29 12/30/80 21: 00 0.142 3. 52 33 1. 54 0.350
0.200 10 10/07/81 1:00 0.140 3.48 34 1. 49 0.330
0.146 30 1/06/83 14:00 0.135 3.40 35 1. 45 0.310
0.073 44 12/13/83 5:00 0. 133 3.38 36 1. 41 0.291
0.074 43 11/04/84 9:00 0 .133 3.38 37 1. 37 o. n1
0.181 13 1/19/86 11 :00 0.127 3.28 38 1. 33 0.251
0.225 8 11/24/86 14:00 0.125 3.27 39 1. 30 0.231
0.109 40 12/09/87 23:00 0.109 3.09 40 1.27 0. 211
0. 071 46 11/06/88 0:00 0.105 3.04 41 1. 24 0 .191
1.19 1 1/09/90 10:00 0.081 2. 96 42 1. 21 0.171
0.303 7 4/05/91 7:00 0.074 2.91 43 1. 18 0.151
0 .162 21 1/31/92 6:00 0.073 2.86 44 1.15 0.131
B-69
SE 14.fn Street-June2007
0.070 47 1/26/93 6: 00 0.072 2.80 45 1. 12 0 .111
0.062 49 2/17/94 23:00 0. 071 2. 74 46 1. 10 0. 091
0.178 15 12/27/94 20:00 0.070 2.60 47 1. 08 0. 071
0.932 3 2/09/96 2:00 0.066 2.38 48 1. 05 0.051
0.439 6 1/02/97 12:00 0.062 2.13 49 1. 03 0.031
0.105 41 1/24/98 23:00 0.061 1. 99 50 1. 01 0. 011
Computed Peaks 1. 36 5.24 100.00 0.990
Computed Peaks 0. 959 5.18 50.00 0.980
Computed Peaks 0.666 5.13 25.00 0. 960
Computed Peaks 0.403 5.06 10.00 0.900
Computed Peaks 0.364 5.05 8.00 0.875
Computed Peaks 0. 2 68 5.02 5.00 0.800
Computed Peaks 0.144 3.54 2.00 0.500
Computed Peaks 0.097 3.01 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File: c-270. tsf Mean= -0.263 StdDev= 0.125
Project Location:Sea-Tac Skew~ 0. 392
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0.573 20 2/16/49 21 :00 1.10 1 89.50 0.989
1. 06 2 3/03/50 16: 00 1. 06 2 32.13 0. 969
0.614 18 2/09/51 2:0C 0.982 3 19.58 0.949
0.415 43 10/15/51 13:00 0.910 4 14. 08 0.929
0.419 42 3/24/53 15:00 0. 7 68 5 10.99 0.909
0. 52 6 26 12/19/53 19: 00 0.758 6 9.01 0.889
0.530 25 11/25/54 2:00 0.728 7 7.64 0.869
0.534 24 12/20/55 17:00 0. 721 8 6.63 0.849
0.646 14 12/09/56 14:00 0.707 9 5. 86 0.829
0.547 21 12/25/57 16: DO 0.701 10 5.24 0.809
0.399 46 1/26/59 20:00 0.659 11 4.75 0.789
0.540 22 11/20/59 5:00 0.653 12 4.34 0.769
0.474 34 2/14/61 21:00 0.647 13 3. 99 0. 749
0.447 39 11/22/61 2:00 0.646 14 3.70 0.729
0.479 31 12/15/62 2:00 0.637 15 3.44 0.709
0.520 28 12/31/63 23:00 0.633 16 3.22 0.690
0. 4 60 38 12/21/64 4: 00 0.622 17 3.03 0.670
0.472 35 1/05/66 16:00 0. 614 18 2.85 0.650
0. 721 8 11/13/66 19:00 0.606 19 2.70 0.630
0.758 6 8/24/68 16:00 0.573 20 2.56 0.610
0.433 41 12/03/68 16:00 0.547 21 2.44 0.590
0.478 32 1/13/70 22:00 0.540 22 2.32 0.570
0. 4 64 36 12/06/70 8:00 0.539 23 2.22 0.550
0.768 5 2/27 /72 7:00 0.534 24 2.13 0.530
0.413 44 1/13/73 2:00 0.530 25 2.04 0.510
0. 524 27 11/28/73 9:00 0. 52 6 26 1. 96 0. 4 90
0.707 9 12/26/74 23:00 0.524 27 1. 89 0.470
0.436 40 12/02/75 20:00 0.520 28 1. 82 0.450
0.461 37 8/26/77 2:00 0.510 29 1. 75 0.430
0.659 11 9/22/78 19: 00 0. 4 92 30 1. 70 0.410
0.539 23 9/08/79 15:00 0. 47 9 31 1. 64 0.390
0.633 16 12/14/79 21 :00 0.478 32 1. 59 0.370
0.637 15 11/21/80 11 :00 0.476 33 1. 54 0.350
0.910 4 10/06/81 15:00 0.474 34 1. 49 0.330
0.606 19 10/28/82 16:00 0. 472 35 1. 45 0.310
0. 510 29 1/03/84 1:00 0. 4 64 36 1. 41 0. 2 91
0.407 45 6/06/85 22 :00 0. 4 61 37 1. 37 0. 271
0.647 13 1/18/86 16: 00 0. 4 60 38 1.33 0.251
B-70
SE 14,fh Street-June 2007
0. 728 7 10/26/86 0:00 0.447 39 1. 30 0.231
0.317 49 1/14/88 0:00 0.436 40 1.27 0. 211
0.383 47 8/21/89 17:00 0.433 41 1.24 0.191
1.10 1 1/09/90 6:00 0.419 42 1. 21 0 .171
0.982 3 11/24/90 8:00 0. 415 43 1.18 0.151
0. 492 30 1/27/92 15:00 0. 413 44 1.15 0.131
0.294 50 12/10/92 6:00 0.407 45 1. 12 0 .111
0.339 48 11 /30/93 22: 00 0.399 46 1.10 0. 091
0.476 33 11/30/94 4:00 0.383 47 1. 08 0. 071
0.701 10 2/08/96 10:00 0.339 48 1. 05 0.051
0.622 17 1/02/97 6:00 0. 317 49 1. 03 0.031
0.653 12 10/04/97 15:00 0.294 50 1. 01 0.011
Computed Peaks 1.16 100.00 0.990
Computed Peaks 1. 04 50.00 0.980
Computed Peaks 0.936 25.00 0.960
Computed Peaks 0.797 10.00 0.900
Computed Peaks 0.769 8.00 0.875
Computed Peaks 0.690 5.00 0.800
Computed Peaks 0.536 2.00 0.500
Computed Peaks 0.437 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-300.tsf Mean= -0.057 StdDev= 0 .172
Project Location:Sea-Tac Skew= 0.335
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
1. 02 17 2/16/49 21:00 2.19 1 89.50 0.989
2.17 2 3/03/50 16:00 2.17 2 32.13 0.969
1. 35 8 2/09/51 14: 00 1. 90 3 19.58 0.949
0. 718 38 1/30/52 8:00 1. 58 4 14. 08 0. 929
0.602 42 3/24/53 15:00 1. 58 5 10.99 0.909
0.842 21 12/19/53 19:00 1. 50 6 9.01 0.889
1. 05 16 2/07/55 17:00 1. 36 7 7.64 0.869
1. 08 15 12/20/55 17:00 1. 35 8 6.63 0.849
1.11 14 12/09/56 14: 00 1. 32 9 5.86 0.829
0. 796 27 12/25/57 16:00 1. 20 10 5.24 0.809
0.644 41 1/26/59 20:00 1. 20 11 4.75 0.789
1.14 13 11/20/59 21:00 1. 15 12 4.34 0.769
0. 775 32 2/14/61 21: 00 1.14 13 3.99 0.749
0.543 45 11/22/61 2:00 1.11 14 3.70 0. 72 9
0. 791 29 12/15/62 2:00 1. 08 15 3.44 0.709
0.838 22 12/31/63 23:00 1. 05 16 3.22 0.690
0. 672 40 12/21/64 4:00 1. 02 17 3.03 0. 670
0. 771 34 1/05/66 16:00 1. 02 18 2.85 0.650
1. 20 11 1/19/67 14:00 0.919 19 2.70 0.630
0.919 19 8/24/68 16: 00 0.855 20 2.56 0.610
0. 7 63 35 12/03/68 16:00 0.842 21 2.44 0.590
0.775 31 1/13/70 23:00 0.838 22 2.32 0.570
0. 774 33 12/06/70 8:00 0.831 23 2.22 0.550
1. 50 6 2/27/72 7:00 0.829 24 2.13 0.530
0.686 39 1/13/73 2:00 0.815 25 2.04 0.510
0.793 28 11/28/73 9:00 0.807 26 1. 96 0. 4 90
1. 32 9 12/26/74 23:00 0. 796 27 1. 89 0.470
0.782 30 12/02/75 20:00 0.793 28 1. 82 0.450
0.512 47 8/26/77 2: 00 0.791 29 1. 75 0.430
0. 82 9 24 9/22/78 19:00 0.782 30 1. 70 0.410
0.563 44 9/08/79 15:00 0.775 31 1. 64 0.390
1. 02 18 12/14/79 21:00 0.775 32 1. 59 0.370
B-71
St: 144°' Street-June 2007
0.831 23 11/21/80 11: 00 0. 774 33 1. 54 0.350
1. 58 4 10/06/81 15:00 0.771 34 1. 49 0.330
0.807 26 1/05/83 8:00 0.763 35 1. 45 0.310
0.815 25 1/03/84 1:00 0.762 36 1. 41 0. 2 91
0.469 48 6/06/85 22:00 0.759 37 1. 37 0. 271
1. 36 7 1/18/86 16: 00 0.718 38 1. 33 0.251
1. 20 10 11/24/86 3:00 0.686 39 1. 30 0.231
0.539 46 1/14/88 12:00 0.672 40 1.27 0. 211
0.444 49 11/05/88 14:00 0.644 41 1. 24 0.191
2.19 1 1/09/90 6:00 0.602 42 1.21 0 .171
1. 90 3 11/24/90 8:00 0.568 43 1.18 0.151
0.759 37 1/27/92 17:00 0.563 44 1.15 0.131
0.568 43 3/22/93 22:00 0.543 45 1.12 0 .111
0.368 50 11/30/93 22:00 0.539 46 1.10 0.091
0. 762 36 2/18/95 20:00 0.512 47 1. 08 0.071
1. 58 5 2/08/96 10:00 0.469 48 1. 05 0.051
1.15 12 1/02/97 6:00 0.444 49 1. 03 0. 031
0.855 20 10/04/97 15:00 0.368 50 1. 01 0. 011
Computed Peaks 2.42 100.00 0.990
Computed Peaks 2.12 50.00 0.980
Computed Peaks 1. 83 25.00 0. 960
Computed Peaks 1. 4 7 10.00 0.900
Computed Peaks 1. 40 8. 00 0.875
Computed Peaks 1. 21 5.00 0.800
Computed Peaks 0.859 2. 00 0.500
Computed Peaks 0.647 1.30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-304.tsf Mean;=:: 0.141 StdDev~ 0.132
Project Location:Sea-Tac Skew= 0.426
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
1. 49 19 2/16/49 21: 00 2.93 1 89.50 0.989
2.86 2 3/03/50 16:00 2.86 2 32.13 0. 969
1. 65 13 2/09/51 2:00 2. 61 3 19.58 0.949
1. 0 6 42 1/30/52 8:00 2.38 4 14. 08 0. 929
1. 04 44 3/24/53 15:00 2. 04 5 10.99 0.909
1. 34 25 12/19/53 19:00 1. 92 6 9.01 0.889
1. 40 22 2/07/55 17:00 1. 86 7 7.64 0.869
1. 42 21 12/20/55 17:00 1. 84 8 6.63 0.849
1. 67 12 12/09/56 14: 00 1. 78 9 5.86 0.829
1. 37 24 12/25/57 16:00 1. 7 5 10 5.24 0.809
1. 01 45 1/26/59 20:00 1. 74 11 4.75 0.789
1. 40 23 11/20/59 5:00 1. 67 12 4. 34 0.769
1. 21 33 2/14/61 21:00 1. 65 13 3.99 0.749
1. 09 41 11/22/61 2:00 1. 63 14 3.70 0. 729
1. 23 31 12/15/62 2:00 1. 62 15 3.44 0.709
1. 32 26 12/31/63 23:00 1. 62 16 3 .22 0.690
1.15 37 12/21/64 4:00 1. 62 17 3.03 0.670
1. 20 34 1/05/66 16:00 1. 58 18 2.85 0.650
1. 78 9 11/13/66 19:00 1. 49 19 2. 70 0.630
1. 84 8 8/24/68 16:00 1. 47 20 2.56 0. 610
1.12 39 12/03/68 16: 00 1. 42 21 2.44 0. 590
1.22 32 1/13/70 22:00 1. 40 22 2.32 0.570
1. 20 35 12/06/70 8: 00 1. 40 23 2.22 0.550
2.04 5 2/27 /72 7:00 1. 37 24 2.13 0.530
1. 0 6 43 1/13/73 2:00 1. 34 25 2.04 0.510
1. 32 27 11/28/73 9:00 1. 32 26 1. 96 0.490
B-72
SE 14.¢» Street-June 2007
1. 86 7 12/26/74 23:00 1. 32 27 1. 89 0.470
1. 14 38 12/02/75 20:00 1. 30 28 1. 82 0.450
1. 10 40 8/26/77 2:00 1.27 29 1. 75 0.430
1. 62 15 9/22/78 19:00 1. 24 30 1. 70 0.410
1.27 29 9/08/79 15:00 1. 23 31 1. 64 0.390
1. 62 17 12/14/79 21:00 1. 22 32 1. 59 0.370
1.58 18 11/21/80 11: 00 1. 21 33 1. 54 0.350
2.38 4 10/06/81 15:00 1. 20 34 1. 49 0.330
1. 47 20 10/28/82 16:00 1. 20 35 1. 45 0.310
1. 30 28 1/03/84 1:00 1.17 36 1. 41 0. 2 91
0.978 46 6/06/85 22: 00 1.15 37 1. 37 0. 271
1. 75 10 1/18/86 16:00 1. 14 38 1. 33 0.251
1. 74 11 10/26/86 0:00 1.12 39 1. 30 0.231
0.782 49 1/14/88 12:00 1.10 40 1.27 0. 211
0. 897 47 8/21/89 17:00 1. 0 9 41 1. 24 0.191
2.93 1 1/09/90 6:00 1. 0 6 42 1.21 0 .171
2.61 3 11/24/90 8:00 1. 0 6 43 1.18 0.151
1. 24 30 1/27/92 15:00 1. 04 44 1.15 0.131
0.756 50 3/22/93 22:00 1. 01 45 1.12 0 .111
0.806 48 11/30/93 22:00 0.978 46 1.10 0.091
1.1 7 36 11/30/94 4:00 0.897 47 1. 08 0. 071
1. 92 6 2/08/96 10:00 0.806 48 1. 05 0. 051
1. 63 14 1/02/97 6:00 0.782 49 1. 03 0.031
1. 62 16 10/04/97 15:00 0.756 50 1. 01 0. 011
Computed Peaks 3.09 100.00 0. 990
Computed Peaks 2.77 50.00 0.980
Computed Peaks 2. 4 6 25.00 0. 960
Computed Peaks 2.07 10.00 0.900
Computed Peaks 1. 99 8.00 0.875
Computed Peaks 1. 77 5.00 0.800
Computed Peaks 1. 36 2.00 0.500
Computed Peaks 1. 0 9 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-306.tsf Mean= -1.180 StdDev= 0.204
Project Location:Sea-Tac Skew-0.041
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0.081 17 2/16/49 21: 00 0.177 1 89.50 0.989
0 .176 2 3/03/50 16: 00 0.176 2 32.13 0. 969
0.126 5 2/09/51 15:00 0.153 3 19. 58 0.949
0.056 37 1/30/52 8:00 0.136 4 14.08 0. 929
0.042 44 3/24/53 15:00 0.126 5 10.99 0.909
0. 0 62 23 12/19/53 19:00 0.122 6 9.01 0.889
0.087 15 2/07/55 19:00 0 .118 7 7.64 0.869
0.089 14 12/20/55 17:00 0 .115 8 6.63 0.849
0.085 16 12/09/56 14:00 0.104 9 5.86 0.829
0.064 21 1/16/58 16:00 0.100 10 5.24 0.809
0.052 40 1/23/59 23:00 0.100 11 4.75 0.789
0.100 10 11/20/59 21: 00 0.100 12 4.34 0.769
0.058 31 2/14/61 21:00 0. 092 13 3.99 0.749
0.037 45 1/02/62 22:00 0.089 14 3.70 0. 72 9
0.059 30 12/15/62 2:00 0.087 15 3.44 0.709
0.062 22 12/31/63 23:00 0.085 16 3.22 0.690
0.047 42 12/21/64 4:00 0.081 17 3.03 0. 670
0.058 32 1/05/66 16:00 0.073 18 2.85 0.650
0.100 11 1/19/67 14:00 0.069 19 2.70 0.630
0.060 25 2/03/68 22:00 0.067 20 2.56 0.610
B-73
SE 14/h Street-June 2007
0.060 27 12/03/68 16:00 0.064 21 2.44 0.590
0.060 28 1/13/70 23:00 0.062 22 2.32 0.570
0.058 33 12/06/70 8:00 0.062 23 2 .22 0.550
0.122 6 2/28/72 3:00 0.061 24 2.13 0.530
0.053 38 1/13/73 4:00 0.060 25 2.04 0.510
0.057 34 1/15/74 2:00 0.060 26 1. 96 0. 4 90
0.104 9 12/26/74 23:00 0.060 27 1. 89 0.470
0.061 24 12/02/75 20:00 0.060 28 1. 82 0.450
0.029 48 8/26/77 2:00 0.059 29 1. 75 0.430
0.057 35 12/10/77 17:00 0.059 30 1. 70 0.410
0.031 47 11/19/78 3:00 0.058 31 1. 64 0.390
0.073 18 12/14/79 21: 00 0.058 32 1. 59 0.370
0.056 36 12/26/80 0:00 0.058 33 1. 54 0.350
0 .118 7 10/06/81 15:00 0.057 34 1. 4 9 0.330
0.069 19 1/05/83 8:00 0.057 35 1. 45 0.310
0.060 26 1/03/84 1:00 0.056 36 1. 41 0. 2 91
0.031 46 2/11/85 3:00 0.056 37 1. 37 0. 271
0 .115 8 1/18/86 16: 00 0.053 38 1. 33 0.251
0.100 12 11/24/86 4:00 0.052 39 1. 30 0.231
0.043 43 1/14/88 12:00 0.052 40 1. 27 0. 211
0. 027 49 12/30/88 5:00 0.048 41 1. 24 0.191
0.177 1 1/09/90 6:00 0.047 42 1. 21 0 .171
0.153 3 11/24/90 8:00 0.043 43 1.18 0.151
0.059 29 1/27 /92 17:00 0.042 44 1.15 0 .131
0.048 41 3/22/93 23:00 0.037 45 1.12 0 .111
0.023 50 2/17/94 18:00 0.031 46 1.10 0.091
0.067 20 2/19/95 18:00 0.031 47 1. 08 0.071
0.136 4 2/08/96 10:00 0. 02 9 48 1. 05 0.051
0.092 13 1/02/97 6:00 D. 027 49 1. 03 0.031
0.052 39 10/04/97 15:00 0.023 50 1. 01 D. 011
Computed Peaks 0.200 100.00 0.990
Computed Peaks 0.176 SO.DO 0.980
Computed Peaks 0.152 25.00 0.960
Computed Peaks 0.121 10.00 0.900
Computed Peaks 0 .115 8.00 0.875
Computed Peaks 0.098 5.00 0.800
Computed Peaks 0.066 2.00 0.500
Computed Peaks 0.046 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-310.tsf Mean= -0.648 StdDev~ 0.233
Project Location:Sea-Tac Skew~ -0.139
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0 .276 16 2/16/49 22:00 0. 627 1 8 9. 50 0.989
0.539 5 3/03/50 16: 00 0. 592 2 32.13 0. 969
0.592 2 2/09/51 18:00 0.561 3 19.58 0.949
0.186 32 1/30/52 9:00 0. 54 9 4 14. 08 0. 929
0 .143 42 1/18/53 19:00 0.539 5 10.99 0.909
0.208 28 1/06/54 5:00 0.456 6 9.01 0.889
0.368 9 2/07/55 21: OD 0.440 7 7.64 0.869
0.313 13 12/20/55 17:00 0. 396 8 6.63 0.849
0.244 21 12/09/56 15:00 0.368 9 5.86 0.829
0.259 20 1/16/58 20:00 0.368 10 5.24 0.809
0.212 24 1/24/59 2:00 0.364 11 4.75 0.789
0 .396 8 11/20/59 21:00 0.317 12 4.34 0.769
0 .215 23 2/24/61 15:00 D. 313 13 3.99 0.749
0.129 44 1/03/62 2:00 0.306 14 3.70 0. 729
B-74
SE 14¢1' Street-June 2007
0.171 36 11/25/62 15:00 0.285 15 3.44 0.709
0.212 25 1/01/64 18:00 0. 27 6 16 3 .22 0.690
0.150 40 11/30/64 12:00 0.273 17 3.03 0. 670
0.163 38 1/06/66 3:00 0.273 18 2.85 0.650
0.364 11 1/19/67 14:00 0.265 19 2.70 0.630
0.216 22 2/03/68 23:00 0. 259 20 2.56 0. 610
0. 211 27 12/03/68 17:00 0.244 21 2. 44 0.590
0.179 34 1/13/70 23:00 0.216 22 2.32 0.570
0.145 41 12/06/70 8:00 0. 215 23 2.22 0.550
0.440 7 2/28/72 3:00 0.212 24 2 .13 0.530
0.195 30 1/13/73 5:00 0. 212 25 2. 04 0.510
0.212 26 1/15/74 2:00 0.212 26 1. 96 0. 4 90
0. 317 12 12/26/74 23:00 0. 211 27 1. 8 9 0.470
0.196 29 12/03/75 17:00 0.208 28 1. 82 0.450
0. 022 50 3/24/77 20:00 0 .196 29 1.75 0.430
0.169 37 12/10/77 17:00 0 .195 30 1. 70 0.410
0.102 46 2/12/79 8:00 0 .190 31 1. 64 0.390
0.273 18 12/15/79 8:00 0.186 32 1. 59 0.370
0.151 39 12/26/80 4:00 0.183 33 1. 54 0.350
0.273 17 10/06/81 15:00 0 .179 34 1. 49 0.330
0. 2 65 19 1/05/83 8:00 0.177 35 1. 45 0.310
0 .177 35 1/24/84 11: 00 0 .171 36 1. 41 0. 2 91
0.085 48 2/11/85 6:00 0.169 37 1. 37 0. 271
0.456 6 1/18/86 21 :00 0.163 38 1. 33 0.251
0.368 10 11/24/86 4:00 0.151 39 1. 30 0.231
0.139 43 1/14/88 12:00 0.150 40 1. 27 0. 211
0.088 47 4/05/89 16: 00 0.145 41 1. 24 0 .191
0. 627 1 1/09/90 9:00 0 .143 42 1. 21 0 .171
0.549 4 4/05/91 2:00 0.139 43 1.18 0.151
0.183 33 1/27/92 17:00 0.129 44 1.15 0.131
0 .190 31 3/23/93 0:00 0.107 45 1. 12 0 .111
0.053 49 3/03/94 4: 00 0.102 46 1. 10 0.091
0.285 15 2/19/95 20:00 0.088 47 1. 08 0.071
0.561 3 2/09/96 1: 00 0.085 48 1. 05 0.051
0. 30 6 14 1/02/97 9:00 0.053 49 1. 03 0.031
0.107 45 1/07/98 10:00 0.022 50 1. 01 0. 011
Computed Peaks 0.743 100.00 0.990
Computed Peaks 0.651 50.00 0.980
Computed Peaks 0.561 25.00 0.960
Computed Peaks 0.444 10.00 0.900
Computed Peaks 0.420 8.00 0.875
Computed Peaks 0.355 5.00 0.800
Computed Peaks 0.228 2.00 0.500
Computed Peaks 0.151 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-320.tsf Mean= -0.597 StdDev~ 0.226
Project Location:Sea-Tac Skew~ -0.141
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0.312 16 2/16/49 22:00 0. 692 1 8 9. 50 0.989
0.636 2 3/03/50 16:00 0.636 2 32 .13 0. 969
0. 621 3 2/09/51 18:00 0. 621 3 19.58 0.949
0.207 33 1/30/52 8:00 0.595 4 14.08 0. 92 9
0.161 42 1/18/53 19:00 0. 58 6 5 10.99 0.909
0.223 29 1/22/54 20:00 0. 4 95 6 9.01 0.889
0. 392 11 2/07/55 21:00 0.485 7 7. 64 0.869
0.354 14 12/20/55 17:00 0.434 8 6.63 0. 84 9
B-75
SE 14.t' Street-June 2007
0.284 20 12/09/56 14:00 0. 411 9 5.86 0.829
0.275 21 1/16/58 20:00 0.408 10 5.24 0.809
0.227 28 1/24/59 2:00 0. 392 11 4.75 0.789
0.434 8 11/20/59 21: 00 0.375 12 4.34 0.769
0. 227 26 2/24/61 15:00 0.356 13 3.99 0.749
0 .142 44 1/02/62 22:00 0.354 14 3.70 0. 729
0.192 36 11/25/62 14:00 0.339 15 3.44 0.709
0.234 25 1/01/64 14: 00 0.312 16 3.22 0.690
0.167 41 11/30/64 22:00 0.301 17 3.03 0.670
0 .191 37 1/05/66 16:00 0.295 18 2.85 0.650
0.408 10 1/19/67 14: 00 0.293 19 2.70 0.630
0.239 22 2/03/68 22:00 0.284 20 2.56 0.610
0.237 23 12/03/68 17:00 0.275 21 2.44 0.590
0. 212 32 1/13/70 23:00 0.239 22 2.32 0.570
0.183 39 12/06/70 8:00 0.237 23 2.22 0.550
0. 4 95 6 2/28/72 3:00 0.235 24 2.13 0.530
0 .215 30 1/13/73 5:00 0.234 25 2.04 0.510
0.235 24 1/15/74 2: 00 0.227 26 1. 96 0.490
0.375 12 12/26/74 23:00 0. 227 27 1. 89 0.470
0.227 27 12/02/75 20:00 0.227 28 1. 82 0.450
0.047 50 3/24/77 19:00 0.223 29 1. 7 5 0.430
0.201 35 12/10/77 17: 00 0.215 30 1.70 0.410
0 .114 46 2/12/79 7: 00 0.215 31 1. 64 0.390
0.295 18 12/15/79 8:00 0.212 32 1.59 0.370
0.180 40 12/26/80 0:00 0.207 33 1. 54 0.350
0.356 13 10/06/81 15:00 0.207 34 1.49 0.330
0. 2 93 19 1/05/83 8:00 0.201 35 1. 45 0.310
0.190 38 1/24/84 11: 00 0 .192 36 1. 41 0.291
0.095 48 2/11/85 5:00 0. 191 37 1. 37 0. 271
0.485 7 1/18/86 20:00 0 .190 38 1. 33 0.251
0. 411 9 11/24/86 4:00 0.183 39 1. 30 0.231
0.161 43 1/14/88 12:00 0.180 40 1.27 0. 211
0.098 47 4/05/89 16:00 0 .167 41 1. 24 0 .191
0. 692 1 1/09/90 9:00 0 .161 42 1. 21 0.171
0.586 5 4/05/91 2:00 0 .161 43 1.18 0.151
0 .215 31 1/27/92 17:00 0.142 44 1.15 0.131
0.207 34 3/22/93 23:00 0.132 45 1.12 0 .111
0.063 49 2/17/94 18:00 0 .114 46 1. 10 0.091
0.301 17 2/19/95 18:00 0.098 47 1. 08 0. 071
0.595 4 2/09/96 1: 00 0.095 48 1. 05 0.051
0.339 15 1/02/97 9:00 0. 063 49 1. 03 0.031
0.132 45 10/30/97 7: 00 0.047 50 1. 01 0. 011
Computed Peaks 0.806 100.00 0.990
Computed Peaks 0.709 50.00 0.980
Computed Peaks 0.614 25.00 0. 960
Computed Peaks 0.489 10.00 0.900
Computed Peaks 0.463 8. 00 0.875
Computed Peaks 0.394 5.00 0.800
Computed Peaks 0.256 2.00 0.500
Computed Peaks 0 .171 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:c-330.tsf Mean= -0.930 StdDev~ 0.187
Project Location:Sea-Tac Skew= 0.198
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0.139 17 2/16/49 21:00 0.307 1 8 9. so 0.989
0.307 2 3/03/50 16:00 0.307 2 32.13 0. 969
B-76
SE 144'h Street-June 2007
o. 193 7 2/09/51 14:00 0. 2 65 3 19.58 0.949
0. 0 97 38 1/30/52 8:00 0.222 4 14. 08 0.929
0.078 43 3/24/53 15:00 0.218 5 10.99 0.909
0 .112 20 12/19/53 19: 00 0.208 6 9.01 0.889
0.144 16 2/07/55 17:00 o .193 7 7.64 0.869
0. 14 9 15 12/20/55 17:00 0 .190 8 6.63 0.849
0 .152 14 12/09/56 14:00 0.182 9 5.86 0.829
0.107 26 1/16/58 16:00 0 .167 10 5.24 0.809
0.087 41 1/23/59 23:00 0.166 11 4.75 0.789
0. 162 12 11/20/59 21:00 0 .162 12 4.34 0. 7 69
0.103 34 2/14/61 21: 00 0.158 13 3.99 0.749
0.068 45 11/22/61 2:00 0.152 14 3.70 0. 729
0.107 27 12/15/62 2:00 0.149 15 3.44 0.709
0 .111 23 12/31/63 23:00 0.144 16 3.22 0.690
0.087 40 12/21/64 4:00 0.139 17 3.03 o. 670
0.103 35 1/05/66 16:00 0.137 18 2.85 0.650
0.166 11 1/19/67 14:00 o .116 19 2.70 0.630
0 .116 19 8/24/68 16:00 0 .112 20 2.56 0.610
0.103 36 12/03/68 16: 00 0 .112 21 2.44 0.590
0.104 33 1/13/70 23:00 0 .112 22 2. 32 0.570
0.105 32 12/06/70 8:00 0 .111 23 2.22 0.550
0.208 6 2/27 /72 7:00 0.109 24 2.13 0.530
0.092 39 1/13/73 2:00 0.108 25 2.04 0.510
0.106 29 11/28/73 9:00 0.107 26 1. 96 0. 4 90
0.182 9 12/26/74 23:00 0.107 27 1. 8 9 0.470
0.106 30 12/02/75 20:00 0.106 28 1. 82 0.450
0.061 47 8/26/77 2:00 0.106 29 1. 75 0.430
0.106 28 9/22/78 19:00 0.106 30 1. 70 0.410
0.065 46 9/08/79 15:00 0.106 31 1. 64 0.390
0.137 18 12/14/79 21:00 0.105 32 1. 59 0.370
0.108 25 11/21/80 11: 00 0.104 33 1. 54 0.350
0.218 5 10/06/81 15:00 0.103 34 1. 49 0.330
0 .112 21 1/05/83 8:00 0.103 35 1. 45 0.310
0.109 24 1/03/84 1:00 0.103 36 1. 41 0.291
0.058 48 2/11/85 3:00 0.102 37 1. 37 0.271
o. 190 8 1/18/86 16: 00 0.097 38 1. 33 0.251
0 .167 10 11/24/86 3:00 0.092 39 1. 30 0.231
0.073 44 1/14/88 12:00 0.087 40 1. 27 0. 211
0.056 49 11/05/88 14:00 0.087 41 1. 24 0.191
0.307 1 1/09/90 6:00 0.078 42 1. 21 0 .171
0. 2 65 3 11/24/90 8: 00 0.078 43 1. 18 0.151
0.102 37 1/27 /92 17:00 0.073 44 1. 15 0.131
0.078 42 3/22/93 22:00 0.068 45 1. 12 0 .111
0.043 50 11/30/93 22:00 0.065 46 1.10 0. 091
0.106 31 2/19/95 17:00 0.061 47 1. 08 0.071
0.222 4 2/08/96 10:00 0.058 48 1. 05 0.051
0.158 13 1/02/97 6:00 0.056 49 1. 03 0.031
0 .112 22 10/04/97 15:00 0.043 50 1. 01 0. 011
Computed Peaks 0.341 100.00 0.990
Computed Peaks 0. 2 98 50.00 0.980
Computed Peaks 0.257 25.00 0. 960
Computed Peaks 0.206 10.00 0.900
Computed Peaks 0 .196 8.00 0.875
Computed Peaks 0 .168 5.00 0.800
Computed Peaks 0 .116 2.00 0.500
Computed Peaks 0.084 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:cb4a.tsf Mean= 0.641 StdDev~ 0.148
Project Location:Sea-Tac Skew= 0. 477
B-77
SE 144"' Street-June 2007
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak -Peaks Rank Return Prob
(CFS) (CFS) Period
4.78 21 2/16/49 21:00 10.01 1 89.50 0. 98 9
9.85 2 3/03/50 16:00 9.85 2 32 .13 0. 969
5. 62 9 2/09/51 2:00 8.83 3 19.58 0.949
3.39 39 1/30/52 8:00 8.04 4 14.08 0. 92 9
3.11 44 3/24/53 15:00 6.85 5 10.99 0. 909
4.19 24 12/19/53 19:00 6. 7 6 6 9.01 0.889
4. 71 22 2/07/55 17:00 6.21 7 7.64 0.869
4. 82 20 12/20/55 17:00 6.01 8 6.63 0. 84 9
5.41 12 12/09/56 14:00 5. 62 9 5.86 0. 82 9
4. 19 25 12/25/57 16: 00 5.52 10 5.24 0.809
3.16 43 1/26/59 20:00 5. 4 9 11 4.75 0.789
4.92 18 11/20/59 21: DO 5. 41 12 4.34 0. 7 69
3.78 34 2/14/61 21: 00 5.37 13 3.99 0.749
3.20 42 11/22/61 2:00 5.35 14 3.70 0.729
3.90 29 12 /15/ 62 2:00 5 .16 15 3.44 0.709
4.13 26 12/31/63 23:00 4. 98 16 3.22 0.690
3.49 37 12/21/64 4:00 4. 92 17 3.03 0. 670
3.79 33 1/05/66 16: 00 4. 92 18 2.85 0.650
5. 4 9 11 11/13/66 19: OD 4.84 19 2. 70 0.630
5.35 14 8/24/68 16: DO 4.82 20 2.56 0.610
3.62 36 12/03/68 16: 00 4.78 21 2.44 0.590
3.85 32 1/13/70 22:00 4. 71 22 2.32 0.570
3.87 30 12/06/70 8:00 4.23 23 2.22 0.550
6.85 5 2/27 /72 7:00 4.19 24 2.13 0.530
3.34 41 1/13/73 2:00 4.19 25 2.04 0.510
4 .11 27 11/28/73 9:00 4 .13 26 1. 96 0. 4 90
6.21 7 12/26/74 23:00 4 .11 27 1. 89 0.470
3.70 35 12/02/75 20:00 4. 07 28 1. 82 0.450
3.05 45 8/26/77 2:00 3.90 29 1. 75 0.430
4. 92 17 9/22/78 19:00 3.87 30 1. 70 0.410
3.38 40 9/08/79 15:00 3. 8 6 31 1. 64 0.390
5. 16 15 12/14/79 21:00 3.85 32 1. 59 0.370
4.84 19 11/21/80 11: 00 3.79 33 1. 54 0.350
8.04 4 10/06/81 15:00 3.78 34 1. 49 0.330
4.23 23 10/28/82 16: 00 3.70 35 1. 45 0.310
4.07 28 1/03/84 1: 00 3. 62 36 1. 41 0.291
2.75 46 6/06/85 22:00 3.49 37 1. 37 0.271
6.01 8 1/18/86 16:00 3.48 38 1. 33 0.251
5.52 10 11/24/86 3:00 3.39 39 1. 30 0.231
2.57 48 1/14/88 12:00 3. 38 40 1.27 0. 211
2.63 47 11/05/88 14:00 3.34 41 1. 24 0.191
10.01 1 1/09/90 6:00 3.20 42 1. 21 0 .171
8.83 3 11/24/90 8: 00 3.16 43 1.18 0.151
3. 8 6 31 1/27/92 15:00 3.11 44 1.15 0.131
2.55 49 3/22/93 22:00 3.05 45 1.12 0 .111
2.19 50 11/30/93 22: 00 2.75 46 1.10 0.091
3.48 38 11/30/94 4:00 2.63 47 1. 08 0.071
6.76 6 2/08/96 10:00 2.57 48 1. 05 0.051
5.37 13 1/02/97 6:00 2.55 49 1. 03 0.031
4.98 16 10/04/97 15:00 2.19 50 1. 01 0. 011
Computed Peaks 10.86 100.00 0.990
Computed Peaks 9.57 SO.OD 0.980
Computed Peaks 8. 3 6 25.00 0. 960
Computed Peaks 6.86 10.00 0.900
Computed Peaks 6.57 8.00 0.875
Computed Peaks 5. 7 6 5.00 0.800
B-78
SE 14-t' Street-June 2007
Computed Peaks 4.25 2.00 0.500
Computed Pea:-::s 3.35 1. 30 0.231
Flow Frequency Analysis LogPearson III Coefficients
Time Series File:cbl8a.tsf Mean= 1. 006 StdDev~ 0.144
Project Location:Sea-Tac Skew= 0.500
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
11.14 18 2/16/49 21:00 22.43 1 89.50 0.989
21. 83 2 3/03/50 16:00 21.83 2 32.13 0. 969
14.72 7 2/09/51 15:00 19.81 3 19.58 0.949
8.02 38 1/30/52 8: 00 18.28 4 14.08 0. 929
7.15 45 3/24/53 15:00 16.05 5 10.99 0.909
9.63 23 12/19/53 19:00 15.54 6 9.01 0.889
11. 00 19 2/07/55 17:00 14. 72 7 7.64 0.869
11.33 17 12/20/55 17:00 14.05 8 6.63 0.849
12.33 14 12/09/56 14:00 13.90 9 5.86 0.829
9.52 25 12/25/57 16: 00 13.36 10 5.24 0.809
7.42 42 1/26/59 20:00 12.80 11 4.75 0.789
12. 72 12 11/20/59 21:00 12.72 12 4.34 0.769
8. 7 6 34 2/14/61 21:00 12.37 13 3.99 0.749
7.24 43 11/22/61 2:00 12.33 14 3.70 0. 729
8.93 30 12/15/62 2:00 11. 96 15 3.44 0.709
9. 51 26 12/31/63 23:00 11. 67 16 3.22 0.690
8.01 39 12/21/64 4:00 11. 33 17 3.03 0.670
8.86 32 1/05/66 16: 00 11.14 18 2.85 0.650
12.37 13 1/19/67 14:00 11. 00 19 2.70 0.630
11. 96 15 8/24/68 16: 00 10.83 20 2.56 0.610
8.55 36 12/03/68 16: 00 10.75 21 2.44 0.590
8. 8 9 31 1/13/70 22:00 10.65 22 2.32 0.570
9.00 29 12/06/70 8:00 9.63 23 2.22 0.550
15.54 6 2/27 /72 7:00 9.57 24 2 .13 0.530
7.85 41 1/13/73 2:00 9.52 25 2.04 0.510
9.13 28 11/28/73 9:00 9.51 26 1. 96 0. 4 90
14.05 8 12/26/74 23:00 9.24 27 1. 89 0.470
8.70 35 12/02/75 20:00 9.13 28 1. 82 0.450
7.23 44 8/26/77 2:00 9.00 29 1. 7 5 0.430
10.83 20 9/22/78 19:00 8.93 30 1. 70 0.410
7.86 40 9/08/79 15:00 8. 8 9 31 1. 64 0.390
11. 67 16 12/14/79 21:00 8. 8 6 32 1. 59 0.370
10.65 22 11/21/80 11 :00 8.84 33 1. 54 0.350
18.28 4 10/06/81 15:00 8.76 34 1. 49 0.330
9.57 24 10/28/82 16:00 8.70 35 1. 45 0.310
9.24 27 1/03/84 1:00 8.55 36 1. 41 0.291
6.55 46 6/06/85 22:00 8.31 37 1. 37 0.271
13.90 9 1/18/86 16:00 8. 02 38 1. 33 0.251
13.36 10 11/24/86 4: 00 8. 01 39 1. 30 0.231
6.18 48 1/14/88 12:00 7.86 40 1. 27 0. 211
6.12 49 11/05/88 14: 00 7. 85 41 1. 24 0 .191
22. 43 1 1/09/90 6:00 7.42 42 1. 21 0.171
19.81 3 11/24/90 8:00 7.24 43 1. 18 0.151
8.84 33 1/27 /92 15:00 7.23 44 1.15 0.131
6.20 47 3/22/93 22:00 7.15 45 1.12 0 .111
5.26 50 11/30/93 22:00 6.55 46 1. 10 0. 091
8.31 37 12/27/94 1: 00 6.20 47 1. 08 0. 071
16.05 5 2/08/96 10:00 6.18 48 1. 05 0.051
12.80 11 1/02/97 6: 00 6.12 49 1. 03 0.031
10.75 21 10/04/97 15:00 5.26 50 1. 01 0. 011
B-79
SE 14.f" Street-June 2007
Computed Peaks 24.66 100.00 0.990
Computed Peaks 21.78 50.00 0.980
Computed Peaks 19.08 25.00 0. 960
Computed Peaks 15.70 10.00 0.900
Computed Peaks 15.05 8.00 0.875
Computed Peaks 13.24 5.00 0.800
Computed Peaks 9.86 2.00 0.500
Co:nputed Peaks 7. 83 1. 30 0.231
B-80
SE J 4.{h Street-June 2007
Table C.1. XP-Storm Conveyance Reach Descriptions
Upstream
Upstream Invert Downstream
Link Node Downstream Elevation Invert Diameter
Name Name Node Name Length ft Roughness ft Elevation ft Shape (Height) ft
P01 CB1 DS 200.00 0.02 355.41 335.00 Circular 2.00
P02 CB2 CB1 200.00 0.02 359.42 357.41 Circular 2.00
P04 CB3 CB2 220.00 0.02 361.55 359.52 Circular 2.00
P06 CB4 CB3 210.00 0.02 363.83 361.60 Circular 2.00
P10 CBS CB4 42.00 0.02 363.88 363.98 Circular 2.00
P12 CB6 CBS 44.00 0.02 364.11 364.13 Circular 2.00
P14 CB7 CB6 150.30 0.02 364.93 364.31 Circular 1.50
P16 CB8 CB7 169.30 0.02 365.45 364.99 Circular 1.50
P19 CB9A CB9 50.00 O.Qt 366.73 366.33 Circular 1.00
P18 CB9 CB8 168.30 0.02 365.93 365.50 Circular 1.50
P20 CB10 CB9 182.40 0.02 366.45 365.98 Circular 1.50
P21 CB10A CB10 39.00 0.02 367.11 366.92 Circular 1.00
P22 CB11 CB10 141.60 0.02 366.95 366.48 Circular 1.50
P70 CB11A CB11 34.00 0.02 367.63 367.49 Circular 1.00
MU11A CB11A CBtOA 120.00 O.Qt 370.48 370.24 Trapezoidc 0.30
MU11B CB11B CB11A 160.00 0.01 370.50 370.38 Trapezoid<: 0.40
MU11B CB11B CB11A 160.00 0.01 370.60 370.48 Trapezoid.: 0.30
P24 CB12 CB11 169.30 0.02 367.52 367.00 Circular 1.50
P26 CB13 CB12 142.40 0.02 367.85 367.52 Circular 1.50
P50 CB14A CB14 52.00 0.01 369.46 369.25 Circular 1.00
ST14A CB14A CB11B 260.00 0.01 371.39 370.70 Trapezoid.= 0.20
P28 CB14 CB13 115.00 0.02 368.15 367.92 Circular 1.50
P30 CB15 CB14 34.00 0.02 368.42 368.20 Circular 1.50
P60 CB15A CB15 52.00 0.01 369.19 368.87 Circular 1.00
OV15A CB15A CB14A 38.00 O.Qt 371.41 371.39 Trapezoidc 0.20
P54 CB14C CB14B 105.00 0.01 370.25 369.89 Circular 1.00
P64 CB15C CB15B 105.00 0.01 373.17 371.37 Circular 1.00
P66 CB15D CB15C 60.00 0.01 379.23 373.30 Circular 1.00
P32 CB16 CB15 197.40 0.02 369.15 368.52 Circular 1.50
P34 CB17 CB16 300.50 0.02 371.76 370.27 Circular 1.50
P36 CB18 CB17 118.30 0.02 372.98 372.41 Circular 1.50
P37 CB18A CB18 37.00 0.02 373.91 374.13 Circular 1.50
D1 CB18A N15A-2 10.00 0.03 375.50 375.40 Trapezoid<: 0.50
P38 CB19 CB18 198.50 0.02 374.69 373.83 Circular 1.00
P40 CB20 CB19 247.50 0.02 375.98 374.74 Circular 1.00
P42 CB21 CB20 192.20 0.02 376.95 375.98 Circular 1.00
POB CB4A CB4 190.00 0.02 366.18 364.73 Circular 1.50
P52 CB14B CB14A 28.00 0.01 369.89 369.49 Circular 1.00
P62 CB15B CB15A 142.00 0.01 371.32 369.39 Circular 1.00
P61 CB15A-1 CB15A 20.00 0.01 370.20 369.27 Circular 1.00
P61 CB15A-1 CB15A 20.00 0.01 372.03 371.31 Trapezoidc 0.30
POSA CB4B CB4A 190.00 0.02 367.26 366.18 Circular 1.50
P08B CB4C CB4B 25.00 0.02 367.63 367.26 Circular 1.50
D2 N15A-2 CB15A-1 590.00 0.03 376.00 370.20 Natural 2.00
Table C.2. XP-Storm Inflows -25-Year Peak Rates
Node Name Constant Inflow ft"·3/s
CB1
CB2
CB3 0.045
CB4 0.206
CB5
CB6 0.242
CB?
CB8 0.198
CB9A 0.297
CB9
CB10
CB10A
C811 0.126
CB11A
CB11B
CB12
CB13
CB14A
CB14 0.200
CB15 0.588
CB15A 0.724
CB14C 0.388
CB15C
CB15D
CB16
CB17
CB18
CB18A
CB19
CB20
CB21
CB4A
CB148
CB158
DS
CB15A-1
CB4B
0.204
19.080
0.157
CB4C 8.360
N15A-2
Table C.3. XP-Storm 25-Year Water Surface Elevations
Ground Max
Elevation Water
Node (Spill Elevation Freeboard
Name Name Crest) ft (ft) (ft)
CB1 CB1 362.33 356.168 6.16
CB2 CB2 363.47 361.096 2.37
CB3 CB3 365.3 363.217 2.08
CB4 CB4 368.98 365.394 3.59
CB5 CBS 369.38 365.546 3.83
CB6 CB6 368.31 365.711 2.6
CB7 CB7 368.87 366.833 2.04
CB8 CB8 369.4 368.097 1.3
CB9A CB9A 369.78 369.244 0.54
CB9 CB9 370.08 369.242 0.84
CB10 CB10 370.57 370.303 0.27
CB10A CB10A 370.54 370.54 0
CB11 CB11 370.85 370.689 0.16
CB11A CB11A 370.78 370.69 0.09
CB11B CB11B 370.9 370.751 0.15
CB12 CB12 371.3 371.084 0.22
CB13 CB13 371.97 371.42 0.55
CB14A CB14A 371.59 371.59 0
CB14 CB14 372.3 371.691 0.61
CB15 CB15 372.37 371.914 0.46
CB15A CB15A 371.61 371.61 0
CB14C CB14C 373.43 371.615 1.81
CB15C CB15C 376.36 373.17 3.19
CB15D CB15D 382.03 379.23 2.8
CB16 CB16 374.35 373.612 0.74
CB17 CB17 378.16 376.102 2.06
CB18 CB18 378.63 377.195 1.44
CB18A CB18A 378.66 377.601 1.06
CB19 CB19 379.29 377.209 2.08
CB20 CB20 379.8 377.226 2.57
CB21 CB21 380.47 377.315 3.16
CB4A CB4A 373.58 368.27 5.31
CB14B CB14B 372.27 371.598 0.67
CB15B CB15B 374.02 371.611 2.41
DS DS 340 337 3
CB15A-1 CB15A-1 372.33 372.33 0
CB4B CB4B 371.36 370.179 1.18
CB4C CB4C 370.43 370.43 0
N15A-2 N15A-2 378 377.519 0.48
Table C.4. XP-Storm 25-Year Flow Rates
Max Max
Velocity Invert Water
Max Flow (fl/s, mis) Node Elevation Elevation
Link Name els fl/s Name ft ft
P01 10.86 10.01 CB1 355.41 356.17
P02 10.86 3.99 CB2 359.42 361.10
P04 10.87 3.91 CB3 361.55 363.22
P06 10.90 4.12 CB4 363.83 365.39
P10 4.89 1.78 CBS 363.88 365.55
P12 4.90 1.84 CB6 364.11 365.71
P14 4.63 2.62 CB7 364.93 366.83
P16 4.63 2.60 CB8 365.45 368.10
P19 0.30 0.38 CB9A 366.73 369.24
P18 4.42 2.49 CB9 365.93 369.24
P20 4.13 2.31 CB10 366.45 370.30
P21 1.33 1.67 CB10A 367.11 370.54
P22 2.80 1.57 CB11 366.95 370.69
P70 0.12 0.15 CB11A 367.56 370.69
MU11A 2.66 1.33 CB11A 367.56 370.69
MU11B 1.96 0.82 CB11B 369.40 370.75
MU11B 0.80 0.58 CB11B 369.40 370.75
P24 2.57 1.44 CB12 367.52 371.08
P26 2.57 1.44 CB13 367.85 371.42
P50 (1.19) (1.50) CB14A 369.46 371.59
ST14A 2.76 1.57 CB14A 369.46 371.59
P28 2.57 1.44 CB14 368.15 371.69
P30 3.56 2.00 CB15 368.42 371.91
P60 (2.07) (2.60) CB15A 369.19 371.61
OV15A 1.40 0.78 CB15A 369.19 371.61
P54 0.39 0.49 CB14C 370.25 371.62
P32 5.04 2.82 CB16 369.15 373.61
P34 5.04 2.82 CB17 371.76 376.10
P36 5.04 2.82 CB18 372.93 377.20
P37 5.13 2.88 CB18A 373.91 377.60
D1 14.66 3.09 CB18A 373.91 377.60
P38 (0.37) 0.20 CB19 374.69 377.21
P40 (0.32) 0.26 CB20 374.72 377.23
P42 0.16 0.87 CB21 375.98 377.32
P08 5.73 3.35 CB4A 366.18 368.27
P52 0.39 0.49 CB14B 369.89 371.60
P61 3.78 4.78 CB15A-1 370.20 372.33
P61 2.55 5.62 CB15A-1 370.20 372.33
P08A 5.73 3.22 CB4B 367.26 370.18
P08B 5.73 3.23 CB4C 367.63 370.43
D2 14.66 8.62 N15A-2 375.00 377.52
Figure C.1. Hydraulic Profile-CB-1 to CB-4C -25-Year Peak
!?OD
'""
350.0 ,_
,.,.
n,o
OS
072 "'' 0:10J!>
D : 2.00 ______ ,.,..,..
121,5 -~-0 21'0.5-.... ,
~y_..ct,11:;iCIMC
O.,~T-Cle:00.'.IJ!Mp~
e115-761 0 ... , ''" 1H1J.
_______ . : -----------=---~----~~--~ ~ -=-.! .~----______ J~-------~--------
1 _______________ , ______ _
C"1 .,.
~-~--~ ----------
~ CR2 D04 w POel cs. llo08 ¢1,U l'C9A i:'t~ 't 1 l'm 1.ee it~ ,,e %":U~ 2 ~ r ti CMOa<C
2.12 2.10
20G 2:t.OC .::1oco IQC.00 ttO.CO D>'
Figure C.2. Hydraulic Profile-CB-4 to CB-15-25-Year Peak
,,,, ""
!72C·
?!10
me
.... , /\__----
,,..
'"" ~· 2S-Y-·C8-+bC6-t!
Da,~T-~:4l1Xl~l4l
l_"l'gl ""' ~t C, ·~9 ,,,,_,
--------
---------~--------,~------
'"' ----
''" ---------------
,,,. ---------~ -------~
"''
''"
ce,i. !"10 cae i-1: Cl(. ,w csr ,ie CM •u e1tt ~ ca,o ~ Cf.11 n.
I MI : 4.Nt.ell -4«,t.» ::I ·~ ·.IQ o. 4C2 2.e3-0: 4C 33' ::): 4..ll U5-C ac )14 Q : 2..57
O : l.CD O :!XI O l!ill J t ,0 o '"'° O 1..!tl D 1.e!O 0 : 1$
ca 1: ~ ca,t r.e ea1•PllX8~t ue ::i: :r. 1 ~. o l !i 1~ 14-
0 : I.SI :,_ 1.!t-0 : t .~
+-Uco---44.~ ,e'°x:-•~ tee JC ·u..a t-'lt. 1tt1.20--10 ... 40 115-~ 11)<4_00.,
Figure C.3. Hydraulic Profile-CB-15 to CB-18A-25-Year Peak
""'
'" '"" nie.Q. )e.l.J
~Y-·C8-1'tc-Cll-la-.
0,,(tl!T-Ge,0:,.(C91ef:,3Cll ,, ... 311.Q -4!7 1 "'' ""
t --------------
-----------1----l --------------------·------
a1' ... ,.,.
a '°' C . l!(J
-----------!QUO-
""" .... .... o :,.O'
:.1.~ '"" .,. ~ ca1.s rn ca1&A
Q '·°' ·~ Q 4 0? )°" o. 1.eo o , ,:
,.,. .r.co--
~ rr
~ \
\ I
I
\
~ \ I
I
\
\ ~
\
l! \
I
~-1 \
~l~ ·e ~P
~l -~ ~~ ! I
i I
I
~ I 1 -
'
~ '
~ I.
I ,
I i I
i
I
\
0
.
\ \
I
\ \ I
I I
I
8"
0
i= .~ u ~;
!!"
8
"
~~ B ti 0 j!
?~ e-
-&
~~ i Q
Ii~
::1110 I !!"
l1 ~~ ! o<>
"t
Appendix D. HEC-RAS Analysis of Roadway Conveyance
Description of inputs:
Geometry:
Geometry of roadway based on Barghausen Consulting Engineers field survey from 6/07.
STA Description
0+00 10' west of CB-11A
1+60 1 O'west of CB-11 B
6+60 160' east of CB-15A-1
8+10 290' west of CB-18A
1010 85' west of CB-18A
Flow:
Based on cumulative 100-year peak flow rate to the conveyance system predicted by KCRTS 1-
hour time series minus the estimated capacity of the 18-inch pipe on the south side of SE 144th
Street (5 .0 cfs).
SE 144"' Street -June 2007
380
378-
376
g
C:
i > ti)
[jj
374
372
37J
... -m
u5
I
0 200
SE 144th Roadway Conveyance Plan: SE144th Roadway 6/17/2007
Geom: SE144th Flow: Roadway Q
144th 1
0 -... + CD (X)
m .lll u5 en
I I
400 600 800
Main Channel Distance (ft)
0 + 0 -c7j
I
1000
I
1200
Legend
WS Ex is
Ground
ROB
SE 144th Roadw ay Conveyance Plan: SE 144th Roadway 6/17/2007
Geom: SE144th Flow: Roadway Q
River = 144th Reach= 1 RS= 1010 Sl.8 10•10
.01 .035
393-j ' L-nd
WS Exis --Ground • g " / I Bani( Sta
I 380:
3791 iii
378
3771
376 ·--, ---,
-30 -20 -10 0 10 20 30
Station (ft)
SE 144th Roadway Conveyance Plan: SE144th Roadw ay 6/17/2007
Geom: SE144th Fklw: Rooaway a
River = 144th Reach ; 1 RS= 810 Sta 8+10
.022 .01 .035
378.0 ~ 377.5 WS Exis ,------------1--
377.0 Groond • g Bank Sta
§
~ 376.0
iii
375.5
375-{
374.5 --,
-30 -20 -10 0 10 20 30 40 50
Station (ft)
SE 144th Roadway Conveyance Plan: SE 144th Road way 6/17/2007
Geom: S E144th Fk)w: Roadway Q
Rive r = 144th Reach = 1 RS = 660 S ta 6+60
.022 .01
375.5-I L-nd
3750-~ INS Exis
1 --374.5r-----Ground • §: 374 .0 • Bank Sta
~
~ 373.5
iii 373.0
372.5
372.0
371 .5 I ' ,---·-
-30 -20 -10 0 10 20 30 40 50
Station(ft)
374.5 -r-022
374.0
373.5
g 373.0
g
ll 372.5 .,,
w 372.0
371 .5
371.0
370.51
·30
372.5-
372.0
371.5
e g 371.0
ii
i w
370.5
370.0
369.5
369.0
-60
SE 144th Roadway Conveyance Plan: SE144th Roadway 6/17/2007
Geom: SE 144th F low: RoadwayQ
Rive r = 144th Reaeh = 1 RS : 160 Sta 1+60
-----------------------.01 .022-------------->1
-20
.022
-40
-10 0 10
Stabon (ft)
20
SE 144th Roadway Conveyance Plan : SE144th Roadway 6/17/2007
Geom: SE144lh Flow: Roadway Q
River= 1«1h Reach = 1 RS :. 0 Sta 0-+-00
' 30 40
---------------------.01 .022------>i
·20 0
Stalion (ft)
-·--.,.-----.---,---,
20
-,-
40
Legend
WS E<is -Ground
I Ban: Ste
50
60
Legend
WSE,c;s I
~ • Bank Ste
HEC-RAS Plan : SE144th River: 144th Reach: 1 Profile : Exis --
Reach River Sta Profile QTotal Min Ch El W.S. Elev CritW.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chi
(cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
1 1010 Exis 20.09 378.07 378.44 378.22 378.56 0.005394 2.69 7 .44 1 20.08 1.35 --->----
1 810 Exis 20.09 376.47 376.22 376.22 376 .57 0.023460 l 4.23 6.22 0.00
1 660 Exis 20.09 373.69 373.70 373.33 373 .84 0 .006877 0.31 I 6.62 7.79 0.86
1 160 Exis 22.42 370.90 371.63 371.63 371 .77 0.002867 3.25 1 7.92 28.69 1.12
1 0 Exis 22.42 370.70 371.16 371.14 371 .27 0 .003401 3.00 ' 9.76 44.46 1.17
HEC-RAS Plan: SE144th River: 144th Reach: 1 Profile: Exis ----------V elH-ead -1 Frctn Loss
--
Reach River Sta Profile E.G . Elev W.S . Elev C&ELoss Q Left a Channel QRight Top Width
(ft) (ft) (ft) (ft) (ft) (cfs) (cfs) (cfs) (ft) -
1 1010 Exis 378.56 378.44 0.11 1.97 0.02 0.24 4.43 15.42 20.08
1 810 Exis 376.57 376.22 0 .35 1.74 0.06 20.09 6.22
1 660 Exis 373.84 373.70 0.14 2.07 0 .00 0 .00 20.09 7.79
1 160 Exis 371.77 371.63 0.14 0.50 0.01 0.31 18.59 3.52 28.69
1 0 Exis 371 .27 371.16 0.11 0.16 15.32 6.93 44.46
-~~-~-~--~----~--~-··-------~--~----------------ft ---• ·-----~ • • • • a· • w • • ~-.. ·1111 • • • • ·a'• -. m --... -----------. ~ --. . . .. -1-.... ---.. -------· --· ----~-"--"·--~-----· . ---"' .... ---......... ----......
lll8 a N ,.J_ -·-a .... _ -.*w ..... ~.---~ --,.. .. r .. • . ---.. -------· . -..... _ ---...... ... --~ --·-----~ ---. ~. ( JIii .. -... -.. --.. -. " ... "" "" --"" -..
---• fJI/( -.. "" --··· ...... ""I ---..... -. -
• -.. -----.. -~·--.. r -... T_ -~ -
• CM. -R ----·-R -W -•.• -·. ·-----~---------------..... --...... -------·-"" -. '~"--~----~---~-----~----. ----"-------~--. , _ ...... _ ,.. ... -_ ... _. -.... -... ,_ .. _ ---.. -----
-• ---~ -a --D M -• ----• R ·--------~----------. --.... "" -""'" .. -...... -..
-~ ~ iW ... it( l'iii 1'11'..· -... .. ... --.... -· ... -..... -----• -. . ----··---------------~--~~--------------"~-----~~-·---ff·--------~· ~~--~--q·-~ --------------~-~-~--u·-~-~«~-~-111/1.i ,,,.. ""' .. pi/'"'-~ 11;\ ""' ,,.. "' .... "" M! )"'4 "" i
....... )ff ........ ...,.., ... t# .. ,, ..... ,;o11 ,. .... * JOI .._
-~~~~~~w~---~~-~~ ---~--~~» .. ·----~ ~ ... ~ ,,., ~ -.... :"'! .. ""' i,,,: ·"" ~ .. ~ ~
""'. ~ "" . .,. ""' ·r,,t ~ • i,, ... "" >s r .......... "" ~
• ,& "" Mil ""·* ........... ~ ,... .. )!Ii I« loll' 1'11
<P "!It t,t. ,er..~ .. .i,' ,i,,o. ,,. .. OIi ._ -,.. A lG< ""
. .... ... -"' -'" . 'r.,i; -•• .. ... ... .. .., .. )eo'.
17 ~ .,. ~ "" ,. .. }"'.."' "" • .. .. .. ~ )<14 ·. ~~~---~~~P**~-~--» ... , "" .. -· .... ).It 't.: ),i,.; ,... '<if! ... -· ...... "" . T{' ni loOI"* .. WI Oil • • .., * ,w-. )<II!:-. ~ ~
~la,l\o(Mlrw,·M n _. W ......... ,.._,.. •..
n•·l"l\.,._#i;,a,;.,...wl• ... wl9'!• ..,..,., ·•.''IPi "" 1'11: tot·.,. • .. n "' w .411 • -.
M .. "" ·~_.u ¥ ' lit Ult "" W. ."°* ,.._.
Ed McCarthy . P.E ., P.S.
995 7 171 "'1 Aven ue SE
Ren t on. WA 98059
Tel 1425) 27 1-5734
Fax (425) 271-3432
HYDROLOGY a HYDRAULICS • ENGINEERING
ED MCCARTHY, P.E., PS
Hydrology• Hydraulics• Engineerinq
March 3, 2008
Mr. Bruce Whittaker
King County DOES
900 Oakesdale Avenue SW
Renton, WA 98055
Re: Liberty Gardens, Cavalla Development, and Threadgill Plat
Recommended Stormwater Mitigations
Dear Mr. Whittaker;
9951 171 Avenue SE
Henton. WA 98059
(425) 271-5734
FAX (425) 271-3432
As you are aware, the proposed developments of Liberty Gardens, Cavalla, and a portion of the
Threadgill Plat all drain to the conveyance system along SE 144•h Street (Figure 1). The results
of the hydraulic assessment I prepared for the downstream conveyance system (June 15, 2007)
predicted flooding along the north side of SE 144•h Street and at the intersection of l 60'h Avenue
SE. There has also been residential flooding at SE 142nd Place, which is adjacent and tributary to
the downstream system of the proposed developments. After consideration of the basin and
downstream conditions, I offer the stormwater mitigations described below for the proposed
plats to address existing flooding problems along SE 144th Street and at the end of SE 142nd
Place.
Onsite Stormwater Mitigation
Conservation flow control standards are required for the proposed Liberty Gardens, Cavalla, and
Threadgill developments (King County Department of Natural Resources, January 2005). The
hydraulic analysis I prepared (June 15, 2007) indicates that the 18-inch diameter pipe along the
south side of SE 144th Street has a capacity of 4 to 6 cubic feet per second. Flows with return
periods of 2 to 5 years likely surcharge the 18-inch diameter pipe system. The roadway and ditch
system along the north side of SE 144th Street convey the major portion of higher flows. A HEC-
RAS analysis of the roadway conveyance system (Ed McCarthy, PE, PS, June 2007) for the I 00-
year peak rate indicates that the ditch system between 162nd Avenue SE and 160th Avenue SE
has adequate capacity to convey the 100-year peak rate. However, driveway culverts along this
reach as well as the culverts at the intersections of 1601h Ave SE and 161 '1 Ave SE would be
overtopped.
The driveways along the north side of SE 144th Street generally rise above the street as they
approach the residence they access. Representative driveways along the north side of SE 144th
Street that would be flooded with higher flows are illustrated in Photos I and 2 of Attachment A.
As the photographs suggest, the driveway would easily be discemable under a situation where
flood flows inundate the northerly ditch and driveway culverts. The presence of flooding
driveway culverts would not create unreasonable difficulties for emergency access to the
residences.
G=;'\ ·, cc:: ir" \;; : \ '_) < l__:--_J \.:.> 1_ --~ -
I ;-, I
·• '1 1 .... -1 1· 1 ·Jon, ·-l.l,<~ ll . J ,_ ,uc
Mr. Bruce Whittaker
Page 2
March 3, 2008
Based on the HEC-RAS hydraulic model used to assess the conveyance system along SE 144"'
Street, increasing the flow rate by 0.5 cubic foot per second, or more, would increase the flood
stage above one or more of the downstream driveway culverts by more than V. inch (Attachment
B). An increase of more than 0.5 cubic foot per second would occur for the JOO-year peak flow
rate if Flow Conservation Standards were adopted for the proposed projects. As such, this would
constitute aggravating an existing severe flooding problem (King County Surface Water Design
Manual, p. 1-25).
On the other hand, adopting Level 3 flow control would mitigate the impacts of the projects on
this downstream flooding area. The predicted JOO-year stage in the downstream flood flow path
would not be increased. In light of the downstream conditions, providing Level 3 detention
standards is an appropriate stormwater mitigation for each of the proposed developments. For the
Threadgill Plat, this reconunended higher level of flow control would apply only towards the
western portion of the site draining to SE 1441h Street. This mitigation would satisfy Core
Requirement #3 of the Surface Water Design Manual (Table 1.2.3.A on page 1-29).
I conducted KCRTS simulations for the Cavalla and Liberty Gardens plats to estimate the
stormwater detention volumes that would be required to meet Level 3 flow control standards
(Attachment C). For Cavalla, I estimated a required storage volume of 132,300 cubic feet. For
Liberty Gardens, I estimated a required storage volume of 114,600 cubic feet. These estimated
volumes do not include a factor of safety which would increase the required volumes, nor do
they account for the effects of required flow control BMPs, which would reduce the required
storage volume (King County Department of Natural Resources, January 2005).
Extension of 162°d Avenue SE
As part of the proposed plats, 162°d Avenue SE will be extended from SE 144 th Street to SE
136th Street. Like the proposed plats, the proposed roadway will provided stormwater flow
control and water quality treatment. Using the same rational as for the proposed plats, Level 3
flow control and basic water quality treatment would be an appropriate mitigation in managing
stormwater from the proposed roadway.
The proposed extension of 162°d Avenue SE offers an opportunity to improve drainage
conditions for residents at SE 142°d Place. I understand that an open channel along the west side
of the 162°d Avenue SE right-of-way (Figure 2) will be tightlined under proposed developed
conditions. The design of the tightline should be extended far enough upstream such that it
effectively collects drainage that flows along the east boundary of the Gragg property located at
16046 SE 142°d Place. Both the proposed tightline and stormwater control system for 162°d
Avenue SE should have an overflow outlet that maintains the flow route along the north side of
SE 144th Street that is predicted to occur with higher flows.
Proposed Solutions to Drainage Problems at SE 142°d Place
In previous corre':/,'ondence to you, I was supportive of the idea of extending the stormwater pipe
system along 160 A venue SE in effort to direct flows from the drainage course directly north of
SE 142°d Place to the existing 12-inch diameter culvert system along 160"' Avenue SE and
subsequently to the storm conveyance pipe along SE 144"' Street. This modification to the storm
Mr. Bruce Whittaker
Page3
March 3, 2008
system would be intended to relieve some of the flows from the flooding problem at residences
along SE l 42"d Place. After assessing this proposal in additional detail, I am no longer
supportive of it. I believe that adding flows to the pipe system along the lower segment of l 60'h
Avenue SE could create a flooding problem for the residence at the bottom of the hill. With
higher flow rates, a backwater would develop in the flat reach of pipe at the bottom of 160 1
h
Avenue SE and surcharge an inlet pipe adjacent to the residence, increasing the risk of flooding
of the adjacent residential property and structure.
I believe that the most effective way to relieve the drainage problem that now occurs at
properties at the end of SE 142nd Place would be to tightline the channel that now traverses the
east property boundaries of lots located at the end of SE 142"d Place (Figure 2). This
modification to the drainage system could be included in the plans for the proposed extension of
l 62"d Avenue SE. Managing runoff in this manner will resolve a drainage problem that has been
bothersome for several years for at least three residents at SE l 42"d Place.
Gragg Property
The Gragg property, located at 16046 SE 142"d Place, has an additional concern that could be
resolved with the proposed extension and improvements along l 62"d Avenue SE. The onsite
sewage disposal system on the Gragg property has been adversely affected by groundwater
seepage from the channel along the north property boundary. As development in the upstream
basin has increased runoff volumes to the channel, the onsite sewage system has at times failed.
The design of the sanitary sewer along 162nd Avenue SE should include a stub out connection for
the Gragg parcels to correct this ongoing problem.
Please note that the applicants for the proposed plats willingly offer the mitigations that would
benefit the property owners along SE 142"d Place provided that the mitigations can be designed
and implemented without incurring unreasonable delays that may be confronted in acquiring
construction easements, permits, or other construction-related authorizations.
Mr. Bruce Whittaker
Page4
March 3, 2008
If you have any questions regarding my assessment or recommendations, please contact me at
(425) 271-5734.
Sincerely,
tJward D· ft/cC11rt',
Edward McCarthy, Ph.D. P.E.
Mr. Bruce Whittaker
Page 5
March 3, 2008
References
Ed McCarthy, PE, PS. June 16, 2007. SE 1441h Street-Level 3 Downstream Drainage Analysis.
Renton, Wash.
King County Department of Natural Resources, January 2005. King County Surface Water
Design Manual. Seattle.
I
~
) /
\
I
\
\
\},
' \ \
r "--f~/~ '\
\ I
I_)
\
\
\__)
,,,_J
Vicinity Map
Liberty Gardens, Cavalla, Stormwater
and Threadgill Mitigations
King County, Washington
w
Cl)
a> > <(
1 I
_),
SE 128th St J "-
~
SE 144th St
_)
0
2,000
_____ Feet
\_ --
) ?.
\
J \
\ \ ) t~
\
, Ed McCarthy, PE, PS
3/3/08
9957 171 st Averue SE
\
---
Renton. Washington 98059
Phone (4 25) 271-5734 Figure 1
Fax: (425) 271-3432
Legend
D R/D
/ /,/./i /, / ,/1 Flood Flow Path
0
0
Station
' L
Type 2 CB
Type 1 CB
12-18" Pipe/Culvert
24" Pipe/Culvert
Photo ID
See Attachment A
-
'
Downstream Map
Liberty Gardens, Cavalla, Stormwater
and Threadgill Mitigations
King County, Washington
-1'. :
' "-
I
J
w: -.
' (JY.
I~
:SI
0 1
<.0, ....
r
ro > ro
I 0
I
I
I
I ~------..
' \
\
\
\
I
l
I
I
I
I
I
I
' I I ·, I
'· I
'· I
' I ·,. I
' w ,I ·.p I
Qh j
~ "' "O
C:
N
<.O
(/)
C
Q)
"2 ro
('.)
~
Q)
.0
:.J
\
~
rain~ge problems ~r·-· --_ .. ---
t Ching, Gragg , and _-_____ .,.._--
Gammel properties ---i:s;·-8]
. --·------i
-E. 14 ----,. . r f fJ
S 2iidJs () 0 ~
'I G~-og
Ga , rnrne, i
Channel to b~
t1ghtlined '---;~ --________ r i
/
/
/
/
/
CB-7 CB-18
ciHj/J 11 Jt 11 l
0200 Ed McCarthy, PE, PS
99 57 17 1s1Avenue SE
Renton . WasllinglOO 98059
3/3/08
.___ ____ _, Feet Phone: (425) 271 -5734 Figure 2
Fa,.· (425) 271 -3432
Attachment A. Photographs of Downstream Flood Flow Path along SE 144'" Street
Attachment A: Photos of the Downstream System
"' Photo Numbe r 1 "' Photo Number 2
Date of Photo: 1-02-08 Date of Photo: 1-02-08
Location: 16114 SE 144th Street, looking north from S E
1441h Street (Fi1:rnre 2)
Description: Gravel driveway , 12-inc h diameter driveway
Location: 16106 S E 144m Street, looking north from
S E 144th Street (Figure 2)
Description: A sphalt driveway, 12-inch diameter
culvert. driveway culvert.
e Downstream system
T Photo Number 3 T Photo Number 4
Date of Photo: 1-02-08 Date of Photo: 1-02-08
Location: Intersection of 161st Ave SE and SE 144m
Street, looking north from SE 1441h Street
(Figure 2)
Location: Roadside ditch along north side of SE 1441n
Street, looking west (Figure 2)
Description: A 12-inch diameter culvert conveys flow
under 161 s' Ave SE.
Description: The ditch is primarily grass-lined with 12-inch
culvert crossings at driveways and road
intersections.
e Downstream :;ystem
T Photo Number 5 T Photo N umber 6
Date of Photo: 1-02-08 Date of Photo: 1-02-08
Location: Roadside ditch along north s ide of SE 144tn Location: Intersection of 160th Ave SE and SE 1441"
Street, looking west (Fiirure 2 )
Description: The ditch is primarily grass-lined with 12-inch
culvert crossings at driveways and road
intersections.
Street, looking southwest (Figure 2)
Description: Recent improvements to the drainage system
by KC Roads Division are evident in this
ohoto.
Attachment B. HEC-RAS Analysis of Roadway Conveyance
Description of inputs:
Geometry:
Geometry of roadway based on Barghausen Consulting Engineers field survey from June 2007.
STA Descriotion
0+00 10' west ofCB-l IA
1+60 lO'west of CB-1 lB
6+60 160' east ofCB-15A-l
8+10 290' west ofCB-l8A
10+10 85' west ofCB-18A
See Figure 2 for approximate locations of stations.
Flow:
Exis -Based on cumulative I 00-year peak flow rate to the conveyance system predicted by
KCRTS I-hour time series minus the estimated capacity of the 18-inch pipe on the south side of
SE 144th Street (5.0 cfs).
Dev -A simulation was also conducted to determine the incremental flow rate that would
increase the flood elevations by '4 inch. This incremental flow rate was determined to be 0.5 cfs.
g
C
~ • ill
• 380
378
376-I
374
372-
370----~
0
___.-/
'f
c\l
SE 144th Roadway Conveyance Plan: SE144th Roadway 6/17/2007
Geom: SE144th Flow: Roadway Q
--144th 1 -
~ //
/
~
"'
c\l
l
,}
I,
I; j
0 + "' .!'1
U)
~
200 400 600 800
Main Channel Distance {ft)
------},,
'
0 + 0 -
c\l
1000
---------,
1200
Legend
WS Exis
Ground
ROB
-"" _ ____,.,._
g
383-•
'"'
'"'
'""1 "'
'" 1 377J
376+----_,,,
378 0
-.022---+
377 5
377.0
;; i 376.5
! 376.0
"'-·1 315.0
374.5 ---
'"
375.5 r-----
3750
374.5
g 374 o-
i 373 5
~ 373.0
372.5
372.0
371.5
'"
.;o--
-"" -+-
_,,
""
-rn
-,0
SE 144th RoadWay Conveyance Plan: SE144th Roadway 6117/2007
Geom. SE144th Flow Roao-..ay a
R,ver=144lh R8&cti=1 RS=1010 Ste10+10
-.01
-rn '"
Station (fl)
SE 144th Roadway Conveyance Plan· SE144th Roadway 6/1712007
------0,-
Gaom SE144th Flow Roaaway 0
R1"8r = 1441h Raach = 1 RS= 810 Sta 8•10
'"
Sta1,on{fl)
'"
SE 144th Roadway Conveyance Plan: SE144tf1 Roadway 6/17/2007
G!t!lmc SE1441h Flow. Roedway 0
RIV<lf = 144th Roadl ~ 1 RS= 660 Sia 6+60
---01--------
'"
Stehon{fl) "
->I<--"" ' ,-...,.~ :=1 I~
Bank Sta
"
--------------,,
----e,s-----------,
"' '"
---·035 -------~
----------~
"' '"
-'-"'
I ws~~-
' Grou/\0
' .
I Bank S1a
"'
~"'""'~ ,---
1~
Gmurnl
~~;_sia
"'
r• r•
! i
i
-•
iJ
2
I
iJ
-~
+ 'l
iJ
J__
,.,, 0 "' Q
~ [;; ~ ~
HEC-RAS Plan: SE144th River: 144th Reach: 1
'
Reach River Sta Profile Q Total Mln Ch El W.S. Elev CritW.S. E.G. Elev E.G. Slope VelChnl Flow Area Top Width Froode# Chl
~-
(els) (ft) (ft) (ft) (ft) (ft/fl) (ftls) (sqft) (ft)
1 1010 iExis -~~-378.07 378.44 378.22 378.56 0.005394 --~-7.44 20.08 1.35
:eev
-------·-----
1 1010 20.59 378.07 378.45 378.24 378.57 0.005366 2.72 7.60 20.72 1.36
~-~ ----.-------. +---·----· -
1 810 Exls 20.09 376.47 376.22 376.22 376.57 0.023460 4.23 6.22 0.00
1 810 Dev 20.59 376.47 376.24 376.24 376.59 0.023355 4.32 6.28 0.00
--------------------------
.~ ---·. -~ ~ -----· ---·
1 660 Exls 20.09 373.69 373.70 373.33 373.84 0.006877 0.31 6.62 7.79 0861
1 660 Dev 20.59 f---------373.69 373.70 373.35 373.85 0.007151 0.39 6.64 7.92 0.93, ------------·------------
' 11 160 Exls 22.42 370.90 371.63 371.~ 371.77 0.002867 3.25 7.92 28.69 1.12
' -1-----------------~e
1 160 Dev 22.92 370.90 371.64 371.64 371.78 0.002807 3.23 8.14 2929 1.11
. --I ---~· -------------
0.00340~ 3.00
----
1 0 Exl, 22.42 370.70 371.16 371.14 371.27 9.76 44.46 1.17 -
i 1 0 Dev 22.92 370.70 371.17 371.15 371.28 0.003400 3.01 9.95 45.20 1.17 -
Attachment C. KCRTS Detention Volume Estimates
Cavalla -Retention/Detention Facility
Type of Facility:
Side Slope:
Pond Bottom Length:
Pond Bottom Width:
Pond Bottom Area:
Top Area at 1 ft. FB:
Effective Storage Depth:
Stage O Elevation:
Storage Volume:
Riser Head:
Riser Diameter:
Number of orifices:
Detention Pond
2.00 H:lV
214.94 ft
107.47 ft
23100. sq. ft
31414. sq. ft
0. 721 acres
5.00 ft
0.00 ft
132287. cu. ft
3.037 ac-ft
5.00 ft
18.00 inches
3
Full Head Pipe
Orifice # Height
(ft)
Diameter
(in)
Discharge
(CFS)
Diameter
(in)
Area
1 0.00
2 3.00
3 3.60
Top Notch Weir: None
Outflow Rating Curve: None
1. 68
2.90
1. 60
0 .171
0.323
0.082
6.0
4.0
Stage Elevation Storage Discharge
(ft) (ft) (cu. ft) (ac-ft) (cfs)
0.00 0.00 0. 0.000 0.000
0.02 0.02 462. 0. 011 0.010
0.04 0.04 925. 0. 021 0.014
0.05 0.05 1157. 0.027 0.018
0.07 0.07 1620. 0.037 0.020
0.09 0.09 2084. 0.048 0.023
0 .11 0 .11 2549. 0.059 0.025
0.12 0.12 2781. 0.064 0.027
0.14 0.14 3247. 0.075 0.029
0.24 0.24 5581. 0.128 0.038
0.34 0.34 7929. 0.182 0.045
0.44 0.44 10289. 0.236 0.051
0.54 0.54 12663. 0.291 0.056
0.64 0.64 15050. 0.345 0.061
0.74 0.74 17449. 0.401 0.066
0.84 0.84 198 62. 0.456 0.070
0.94 0.94 22288. 0.512 0.074
1. 04 1. 04 24727. 0.568 0.078
1.14 1.14 27180. 0. 624 0.082
1. 24 1. 24 29646. 0.681 0.085
1. 34 1. 34 32125. 0.737 0.089
1. 44 1. 44 34617. 0. 795 0. 092
1. 54 1. 54 37123. 0.852 0.095
1. 64 1. 64 39642. 0.910 0.098
1. 74 1. 74 42174. 0. 968 0.101
Percolation
(cfs)
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Surf
(sq. ft)
23100.
2 312 6.
23152.
23165.
23190.
23216.
23242.
23255.
23281.
23410.
23540.
23671.
23801.
23932.
24063.
24195.
24326.
24459.
24591.
24724.
24857.
24990.
25124.
25258.
25392.
1. 84 1. 84 44720. 1. 027 0.104 0.00 25527.
1. 94 1. 94 47280. 1. 085 0.107 0.00 25662.
2.04 2.04 49853. 1.144 0.109 0.00 25797.
2.14 2.14 52439. 1. 204 0 .112 0.00 25933.
2.24 2.24 55039. 1. 264 o .115 0.00 26069.
2.34 2.34 57653. 1. 324 0 .117 0.00 2 6205.
2.44 2.44 60281. 1. 384 0.120 0.00 26342.
2.54 2.54 62 922. 1. 444 0.122 0.00 26479.
2. 64 2. 64 65576. 1. 505 0.124 0.00 26616.
2.74 2.74 68245. 1. 567 o .127 0.00 26754.
2.84 2.84 70927. 1. 628 0.129 0.00 26892.
2.94 2.94 73623. 1. 690 0.131 0.00 27030.
3.00 3. 00 75247. 1. 727 0.133 0.00 27113.
3.03 3.03 76061. 1. 746 0.135 0.00 27155.
3.06 3.06 76877. 1. 765 0 .142 0.00 27196.
3.09 3.09 77693. 1.784 0.154 0.00 27238.
3.12 3.12 78511. 1. 802 0.169 0.00 27279.
3.15 3.15 79330. 1. 821 0.188 0.00 27321.
3.18 3.18 80150. 1. 840 0 .211 0.00 27363.
3.21 3.21 80972. 1. 859 0.237 0.00 27405.
3.24 3.24 81795. 1. 878 0.250 0.00 27446.
3.34 3.34 84546. 1. 941 0.273 0.00 27586.
3.44 3.44 87312. 2.004 0.294 0.00 27726.
3.54 3.54 90091. 2.068 0.312 0.00 27866.
3.60 3.60 917 6 6. 2.107 0.322 0.00 27950.
3.62 3.62 92325. 2 .119 0.325 0.00 27978.
3.63 3. 63 92 605. 2.126 0.330 0.00 27992.
3.65 3. 65 93165. 2 .139 0.335 0.00 28020.
3.67 3.67 93726. 2.152 0.341 0.00 28049.
3.68 3.68 94006. 2.158 0.349 0.00 28063.
3.70 3.70 94568. 2 .171 0.357 0.00 28091.
3.72 3.72 95130. 2.184 0. 364 0.00 28119.
3.73 3. 73 95411. 2.190 0.369 0.00 28133.
3.75 3.75 95974. 2.203 0.373 0.00 28161.
3.85 3.85 98797. 2.268 0.395 0.00 28302.
3.95 3.95 101635. 2.333 0.416 0.00 28444.
4.05 4.05 104486. 2.399 0.434 0.00 28586.
4.15 4.15 107352. 2.464 0 .452 0.00 28728.
4.25 4.25 110232. 2.531 0.469 0.00 28870.
4.35 4.35 113126. 2.597 0.485 0.00 29013.
4.45 4.45 116034. 2.664 0.500 0.00 29156.
4.55 4.55 118957. 2.731 0.515 0.00 29299.
4.65 4. 65 121894. 2.798 0.529 0.00 29443.
4.75 4.75 124845. 2.866 0.543 0.00 29587.
4.85 4.85 127811. 2.934 0.557 0.00 29731.
4.95 4.95 130792. 3.003 0.570 0.00 29876.
5.00 5.00 132287. 3.037 0.576 0.00 29948.
5.10 5.10 135289. 3.106 1.050 0.00 30093.
5.20 5.20 138306. 3.175 1. 910 0.00 30239.
5.30 5.30 141337. 3.245 3.010 0.00 30385.
5.40 5.40 144383. 3.315 4.320 o.oo 30531.
5.50 5.50 147443. 3.385 5.800 0.00 30677.
5.60 5.60 150518. 3.455 7.240 0.00 30824.
5.70 5.70 153608. 3. 526 7.780 0.00 30971.
5.80 5.80 156713. 3.598 8.280 0.00 31118.
5.90 5.90 159832. 3.669 8.750 0.00 31266.
6.00 6.00 162966. 3.741 9.200 0.00 31414.
6 .10 6.10 166115. 3.813 9.630 0.00
6.20 6.20 169278. 3.886 10.030 0.00
6.30 6.30 172457. 3.959 10.420 0.00
6.40 6.40 175650. 4.032 10.800 0.00
6.50 6.50 178859. 4 .106 11 .160 0.00
6.60 6.60 182082. 4.180 11. 510 0.00
6.70 6.70 185320. 4.254 11. 850 0.00
6.80 6.80 188574. 4.329 12.190 0.00
6.90 6.90 191842. 4.404 12.510 0.00
7.00 7.00 195126. 4.479 12.820 0.00
Hyd Inflow Outflow Peak Storage
Target Cale Stage Elev (Cu-Ft) (Ac-Ft)
1 3.76 ******* 0.79 5.05 5.05 133653. 3.068
2 1. 86 ******* 0.52 4.62 4. 62 121022. 2. 778
3 2.24 ******* 0.45 4.12 4.12 106597. 2.447
4 1. 87 ******* 0.44 4 .11 4 .11 106118. 2.436
5 1. 98 ******* 0.29 3.42 3.42 86855. 1.994
6 1.17 ******* 0.15 3.09 3.09 77629. 1. 782
7 1. 52 ******* 0 .13 2.84 2.84 70843. 1. 626
8 1. 65 ******* 0 .11 1. 97 1. 97 48102. 1.104
----------------------------------
Route Time Series through Facility
Inflow Time Series File:dev.tsf
Outflow Time Series File:rdoutlev3
Inflow/Outflow Analysis
Peak Inflow Discharge: 3.76 CFS at 6:00 on Jan 9 in Year 8
Peak Outflow Discharge: 0.792 CFS at 12:00 on Jan 9 in Year 8
Peak Reservoir Stage: 5.05 Ft
Peak Reservoir Elev: 5.05 Ft
Peak Reservoir Storage: 133653. Cu-Ft
3.068 Ac-Ft
Flow Frequency Analysis
Time Series File:rdoutlev3.tsf
Project Location:Sea-Tac
---Annual Peak Flow Rates---
Flow Rate Rank Time of Peak
(CFS)
0.537 2 2/09/01 20:00
0.130 7 1/07 /02 3:00
0.448 3 3/06/03 22:00
0.108 8 8/26/04 7:00
0.153 6 1/08/05 5:00
0 .291 5 1/19/06 0:00
0.444 4 11/24/06 8:00
0. 792 1 1/09/08 12:00
Computed Peaks
-----Flow Frequency Analysis-------
--Peaks --Rank Return Prob
(CFS) (ft) Period
0. 792 5.05 1 100. 00 0.990
0.537 4. 71 2 25.00 0. 960
0.448 4.13 3 10.00 0.900
0.444 4 .11 4 5.00 0.800
0. 291 3.43 5 3.00 0.667
0.153 3.09 6 2.00 0.500
0.130 2.88 7 1. 30 0.231
0.108 1. 97 8 1.10 0.091
0.707 5.03 50.00 0.980
Flow Duration from Time Series File:rdoutlev3.tsf
Cutoff Count Frequency CDF Exceedence_Probability
CFS % % %
0.008 29873 48. 717 48.717 51.283 0.513E+OO
0.023 5807 9.470 58.187 41. 813 0.418E+OO
31562.
31711.
31860.
32009.
32159.
32309.
32459.
32609.
32760.
32912.
0.038 5674 9. 253 67.440 32.560 0.326E+OO
0.053 5278 8.607 76.047 23.953 0.240E+OO
0.068 4651 7.585 83.632 16.368 0.164E+OO
0.083 3976 6.484 90 .116 9.884 0.988E-Ol
0.098 2180 3.555 93. 671 6.329 0.633E-01
0 .113 1584 2.583 96.254 3.746 0.375E-01
0.128 1475 2.405 98.659 1. 341 0.134E-01
0.144 416 0.678 99.338 0.662 0.662E-02
0.159 47 0.077 99.415 0.585 0.585E-02
0 .174 23 0.038 99.452 0. 548 0.548E-02
0.189 17 0. 028 99.480 0.520 0.520E-02
0.204 17 0. 028 99.507 0. 492 0.492E-02
0.219 18 0. 029 99.537 0. 463 0.463E-02
0.234 18 0. 029 99.566 0.434 0.434E-02
0.249 18 0. 029 99. 596 0.404 0.404E-02
0. 264 39 0.064 99.659 0.341 0. 341E-02
0.279 31 0.051 99.710 0.290 0.290E-02
0.294 31 0.051 99.760 0.240 0.240E-02
0.310 23 0.038 99.798 0. 202 0.202E-02
0.325 16 0.026 99.824 0.176 D.176E-D2
0.340 7 0. 011 99.835 0 .165 0.165E-02
0.355 3 0.005 99.840 0 .160 0.160E-02
0.370 9 0.015 99.855 0.145 0 .145E-02
0.385 10 0.016 99.871 0.129 0.129E-02
0.400 9 0.015 99.886 0 .114 0 .114E-02
0.415 10 0. 016 99.902 0.098 0.978E-03
0.430 10 0. 016 99.918 0.082 0.815E-03
0.445 12 0.020 99.938 0.062 0.620E-03
0.461 11 0.018 99.956 0.044 0.440E-03
0.476 8 0.013 99. 969 0.031 0.310E-03
0.491 4 0.007 99.976 0.024 0.245E-03
0.506 3 0.005 99.980 0.020 0.196E-03
0.521 5 0.008 99.989 0.011 0. ll4E-03
0.536 5 0.008 99.997 0.003 0.326E-04
Duration Comparison Anaylsis
Base File: forest.tsf
New File: rdoutlev3.tsf
Cutoff Units: Discharge in CFS
-----Fraction of Time--------------Check of Tolerance-------
Cutoff Base New %Change Probability Base New %Change
0 .137 0.95E-02 0.72E-02 -24.5 I 0.95E-02 0 .137 0.131 -4.2
0.174 0.63E-02 0.55E-02 -13.2 I 0.63E-02 0.174 0.150 -14.2
0.212 0.50E-02 0.47E-02 -4.9 I O.SOE-02 0.212 0.203 -4.4
0.249 0.37E-02 0.40E-02 8.8 I 0.37E-02 0.249 0.259 3. 8
0.287 0.29E-02 0.27E-02 -6.3 I 0.29E-02 0.287 0 .282 -1. 8
0.324 0.22E-02 0.18E-02 -20. 6 I 0.22E-02 0.324 0.301 -7.0
o .362 O.lSE-02 O.lSE-02 2.2 I O.lSE-02 0.362 0.369 1. 9
0.399 O.lOE-02 0. llE-02 ll .1 I O.lOE-02 0.399 0.413 3.5
0.437 0.62E-03 0. 77E-03 23.7 I 0.62E-03 0.437 0.445 1. 9
0.474 0.34E-03 0.31E-03 -9. 5 I 0.34E-03 0.474 0.473 -0.2
0.512 0.21E-03 0.16E-03 -23.1 I 0.21E-03 0.512 0.501 -2.1
0.549 0.16E-03 O.OOE+OO -100.0 I 0.16E-03 0.549 0.512 -6.8
0.586 O.llE-03 O.OOE+OO -100.0 I 0. llE-03 0. 586 0.522 -11. 0
0. 624 0.16E-04 O.OOE+OO -100.0 I 0.16E-04 0.624 0.537 -14.0
Maximum positive excursion= 0.020 cfs ( 4.9%)
occurring at 0.407 cfs on the Base Data:forest.tsf
and at 0.427 cfs on the New Data:rdoutlev3.tsf
Maximum negative excursion= 0.027 cfs (-16.0%)
occurring at 0.169 cfs on the Base Data:forest.tsf
and at 0.142 cfs on the New Data:rdoutlev3.tsf
Cavalla -Time Series
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Project Location : Sea-Tac
Computing Series forest.ts£
Regional Scale Factor: 1.00
Data Type : Reduced
Creating Hourly Time Series File
Till Forest
Loading Time Series File:C:\KC SWDM\KC DATA\STTF60R.rnf
9.91 acres
Total Area 9.91 acres
Peak Discharge: 0.799 CFS at 9:00 on Jan 9 in Year 8
Storing Time Series File:forest.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Conunand
Compute PEAKS and Flow Frequencies
Loading Stage/Discharge curve:forest.tsf
Flow Frequency Analysis
Time Series File:forest.tsf
Project Location:Sea-Tac
Frequencies & Peaks saved to File:forest.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Computing Interval Locations
Computing Flow Durations
Loading Time Series File:forest.tsf
Durations & Exceedence Probabilities to File:forest.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Project Location : Sea-Tac
Computing Series : dev.tsf
Regional Scale Factor : 1.00
Data Type : Reduced
Creating Hourly Time Series File
Till Grass
Impervious
Loading Time Series File:C:\KC_SWDM\KC DATA\STTG60R.rnf
3.54 acres
Loading Time Series File:C:\KC_SWDM\KC_DATA\STEI60R.rnf
6.37 acres
Total Area 9.91 acres
Peak Discharge: 3.76 CFS at 6:00 on Jan 9 in Year 8
Storing Time Series File:dev.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Loading Stage/Discharge curve:dev.tsf
Flow Frequency Analysis
Time Series File:dev.tsf
Project Location:Sea-Tac
Frequencies & Peaks saved to File:dev.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Computing Interval Locations
Computing Flow Durations
Loading Time Series File:dev.tsf
Durations & Exceedence Probabilities to File:dev.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
exit KCRTS Program
Cavalla -Peak Flow Rates
Flow Frequency Analysis
Time Series File:forest.tsf
Project Location:Sea-Tac
---Annual Peak Flow Rates---
Flow Rate Rank Time of Peak
(CFS)
0.625 2 2/09/01 18:00
0.170 7 1/06/02 3:00
0.463 4 2/28/03 3:00
0.017 8 3/24/04 20:00
0.275 6 1/05/05 8:00
0.480 3 1/18/06 21:00
0.404 5 11/24/06 4:00
0.799 1 1/09/08 9:00
Computed Peaks
Flow Frequency Analysis
Time Series File:dev.tsf
Project Location:Sea-Tac
---Annual Peak Flow Rates---
Flow Rate Rank Time of Peak
(CFS)
1. 86 6 2/09/01 2:00
1. 52 8 1/05/02 16:00
2.24 3 2/27/03 7:00
1. 65 7 8/26/04 2:00
1. 99 4 10/28/04 16:00
1. 98 5 1/18/06 16:00
2.40 2 10/26/06 0:00
3.76 1 1/09/08 6:00
Computed Peaks
Flow Frequency Analysis
Time Series File:rdout.tsf
Project Location:Sea-Tac
---Annual Peak Flow Rates---
Flow Rate Rank Time of Peak
(CFS)
0.536 2 2/09/01 20:00
0.130 7 1/07/02 4:00
0.448 3 3/06/03 22:00
0.107 8 8/26/04 7:00
0.150 6 1/08/05 5:00
0.289 5 1/19/06 0:00
0.442 4 11/24/06 8:00
0.765 1 1/09/08 12:00
Computed Peaks
-----Flow Frequency Analysis-------
--Peaks Rank Return Prob
(CFS) Period
0.799 1 100.00 0.990
0. 625 2 25.00 0. 960
0.480 3 10.00 0.900
0.463 4 5.00 0.800
0.404 5 3.00 0.667
0.275 6 2.00 0.500
0.170 7 1. 30 0.231
0.017 8 1.10 0. 091
0.741 50.00 0.980
-----Flow Frequency Analysis-------
--Peaks Rank Return Prob
(CFS) Period
3.76 1 100.00 0.990
2.40 2 25.00 0.960
2.24 3 10.00 0. 900
1.99 4 5.00 0.800
1. 98 5 3.00 0.667
1. 86 6 2.00 0.500
1. 65 7 1.30 0.231
1. 52 8 1.10 0.091
3.31 50.00 0.980
-----Flow Frequency Analysis-------
--Peaks --Rank Return Prob
(CFS) (ft) Period
0.765 5.04 1 100.00 0.990
0.536 4.70 2 25.00 0. 960
0.448 4 .13 3 10.00 0.900
0.442 4.10 4 5.00 0.800
0.289 3.42 5 3.00 0.667
0.150 3.08 6 2.00 0. 500
0 .130 2.88 7 1.30 0.231
0.107 1. 96 8 1.10 0. 091
0.689 5.02 50.00 0.980
0.8
--+-El<isting ~ Developed
0.7
0.6
ui 0.5
IL
~ ., ,. 0.4
~
3'
0
ii: 0.3
0.2
"
0.1 d
0
E
C.
r;;
i;
' 0
1.00E-05 1.00E-04 1.00E-03 1.00E-02 1.00E-01 1.00E+OO
Probability of Exceedence
Flow Duration Curves for RID. Duration curves are shown at pond outlet. The pond is
designed to meet Level 3 flow control standards.
Liberty Gardens -Retention/Detention Facility
Type of Facility: Detention Pond
Side Slope: 2.00 H:lV
Pond Bottom Length: 144.91 ft
Pond Bottom Width: 72. 46 ft
Pond Bottom Area: 10500. sq. ft
Top Area at 1 ft. FB: 19621. sq. ft
0.450 acres
Effective Storage Depth: 8.00 ft
Stage O Elevation: 403.00 ft
Storage Volume: 114554. cu. ft
2. 630 ac-ft
Riser Head: 8.00 ft
Riser Diameter: 18.00 inches
Number of orifices: 3
Pipe
Orifice * Height
(ft)
Diameter
(in)
1. 30
2.20
2.40
Full Head
Discharge
(CFS)
0.130
0.203
0 .1 71
Diameter
(in)
1 0.00
2 5.60
3 6.80
Top Notch Weir: None
Outflow Rating Curve: None
Stage Elevation Storage
Area
(ft) (ft) (cu. ft) (ac-ft)
0.00 403.00 0. 0.000
0.01 403.01 105. 0.002
0.03 403.03 315. 0.007
0.04 403.04 421. 0.010
0.05 403.05 526. 0.012
0.07 403.07 737. 0.017
0.08 403.08 843. 0.019
0.09 403.09 949. 0.022
0.11 403 .11 1160. 0. 027
0.27 403.27 2867. 0.066
0.42 403.42 4487. 0.103
0.58 403.58 6237. 0.143
0.74 403.74 8010. 0.184
0.89 403.89 9693. 0.223
1. 05 404.05 11510. 0. 264
1. 21 404. 21 13351. 0.306
1.36 404.36 15098. 0.347
1. 52 404.52 16983. 0. 390
1. 68 404.68 18892. 0.434
1. 83 404.83 20704. 0.475
1. 99 404.99 22659. 0.520
2.15 405.15 24638. 0.566
2.30 405.30 26515. 0.609
2.46 405.46 28540. 0.655
2.62 405.62 30590. 0.702
2.78 405.78 32664. 0.750
2.93 405.93 34631. 0. 795
6.0
6.0
Discharge
(cfs)
0.000
0.005
0.008
0.009
0. 011
0.012
0 .013
0.014
0.015
0.024
0.030
0.035
0.039
0.043
0.047
0. 050
0. 054
0.057
0.059
0. 062
0.065
0.067
0.070
0.072
0. 074
0.076
0.078
Percolation
(cfs)
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
o.oo
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Surf
(sq. ft)
10500.
10509.
10526.
10535.
10544.
10561.
10570.
10578.
10596.
10736.
10868.
11010.
11152.
11287.
11431.
11575.
11712.
11859.
12006.
12145.
12294.
12443.
12584.
12736.
12888.
13041.
13185.
3. 09 406.09 36753. 0.844 0.081 0.00 13339.
3 .25 406.25 38 900. 0.893 0.083 0.00 13495.
3.40 406.40 40935. 0.940 0.085 0.00 13641.
3.56 406.56 43130. 0.990 0.086 0.00 13798.
3. 72 406.72 45351. 1. 041 0.088 0.00 13956.
3.87 406.87 47455. 1. 089 0.090 0.00 14105.
4.03 407.03 49725. 1.142 0.092 0.00 14264.
4.19 407.19 52020. 1.194 0.094 0.00 14424.
4.34 407.34 54195. 1.244 0. 096 o.oo 14575.
4.50 407.50 56540. 1. 298 0.097 0.00 14737.
4.66 407.66 58910. 1. 352 0.099 0.00 14899.
4.81 407.81 61157. 1. 404 0.101 0.00 15052.
4.97 407.97 63578. 1. 460 0.102 0.00 15217.
5 .13 408.13 66026. 1. 516 0 .104 0.00 15382.
5.28 408.28 68345. 1. 569 0.105 0.00 15537.
5.44 408.44 70844. 1. 626 0.107 0.00 15703.
5.60 408.60 73370. 1. 684 0.108 0.00 15871.
5. 62 408.62 73688. 1. 692 0 .110 0.00 15892.
5.65 408.65 74165. 1. 703 0 .114 0.00 15923.
5.67 408.67 74484. 1. 710 0.120 0.00 15944.
5.69 408.69 74803. 1. 717 0.129 0.00 15965.
5. 71 408.71 75122. 1. 725 0.140 0.00 15986.
5.74 408.74 75602. 1.736 0.153 0.00 16018.
5.76 408.76 75923. 1. 743 0.163 0.00 16039.
5.78 408.78 7 6244. 1. 750 0.166 0.00 16060.
5.94 408.94 78827. 1. 810 0.188 0.00 16229.
6 .10 409.10 81437. 1. 870 0.206 0.00 16399.
6. 25 409.25 83909. 1. 926 0.221 0.00 16559.
6.41 409.41 86572. 1. 987 0.234 o.oo 16731.
6.57 409.57 89263. 2.049 0.247 0.00 1690 3.
6.72 409.72 91811. 2.108 0. 258 0.00 17065.
6.80 409.80 93179. 2 .139 0. 263 0.00 17152.
6.83 409.83 93694. 2.151 0.266 0.00 1 7185.
6.85 409.85 94038. 2.159 0.273 0.00 17207.
6. 88 409.88 94555. 2 .171 o. 282 0.00 1 7239.
6.90 409.90 94900. 2 .179 0.293 0.00 17261.
6.93 409.93 95418. 2 .191 0.308 0.00 17294.
6.95 409.95 95764. 2 .198 0.325 0.00 17316.
6.98 409.98 96284. 2.210 0.340 0.00 17349.
7.00 410.00 9 6632. 2.218 0.346 0.00 17370.
7.16 410.16 99425. 2. 282 0.380 0.00 17546.
7.31 410.31 102069. 2.343 0.408 0.00 17711.
7.47 410.47 104917. 2.409 0.433 0.00 17888.
7.63 410.63 107793. 2.475 0.456 0.00 18066.
7.78 410.78 110516. 2.537 0. 477 0.00 18233.
7.94 410.94 113447. 2.604 0.497 0.00 18412.
8.00 411. 00 114554. 2.630 0.504 0.00 18480.
8.10 411.10 116408. 2.672 0.978 0.00 18593.
8.20 411. 20 118273. 2.715 1. 830 0.00 18706.
8.30 411.30 120149. 2.758 2.940 0.00 18819.
8.40 411. 40 122036. 2. 802 4.250 0.00 18933.
8.50 411. 50 123935. 2.845 5.730 0.00 19047.
8.60 411.60 125846. 2.889 7.160 0.00 19161.
8.70 411. 70 127768. 2. 933 7.700 0.00 19276.
8.80 411.80 129701. 2.978 8.200 0.00 19390.
8.90 411. 90 131646. 3.022 8.670 0.00 19506.
9.00 412.00 133602. 3.067 9.120 0.00 19621.
9.10 412.10 135570. 3.112 9.550 0.00
9.20 412.20 137549. 3.158 9.950 0.00
9.30 412.30 139541. 3. 203 10.340 0.00
9. 40 412.40 141543. 3.249 10.720 0.00
9.50 412.50 143558. 3. 296 11. 080 0.00
9.60 412.60 145584. 3.342 11. 430 0.00
9.70 412.70 147622. 3.389 11. 770 0.00
9.80 412.80 149672. 3.436 12.100 0.00
9.90 412. 90 151734. 3.483 12.420 0.00
Hyd Inflow Outflow Peak Storage
Stage Elev (Cu-Ft) (Ac-Ft)
1 3.15 0.68 8.04 411. 04
2 1. 56 0.45 7.58 410.58
3 1. 88 0.39 7.24 410.24
4 1. 57 0. 26 6.81 409.81
5 1. 65 0.16 5.75 408.75
6 1.27 0.10 5.09 408.09
7 1. 38 0.08 3.39 406.39
8 0.98 0.10 5. 26 408.26
Hyd RID Facility Tributary Reservoir
Outflow Inflow Inflow
1 0.68 0.12 ********
2 0.45 0.06 ********
3 0.39 0.07 ********
4 0.26 0. 06 ********
5 0.16 0.06 ********
6 0.10 0.05 ******** 7 0.08 0.06 ********
8 0.10 0.04 ********
Route Time Series through Facility
Inflow Time Series File:dev.tsf
Outflow Time Series File:rdoutlev3
POC Time Series File:dsoutlev3
Inflow/Outflow Analysis
115252. 2.646
106940. 2.455
100750. 2.313
93266. 2.141
75705. 1. 738
65382. 1. 501
40741. 0.935
68077. 1. 563
POC Outflow
Target Cale
******* 0. 71
******* 0.47
******* 0.41
******* 0.28
******* 0.16
******* 0.14
******* 0.14
******* 0 .13
Peak Inflow Discharge: 3.16 CFS at 6: 00 on Jan 9 in Year 8
Peak Outflow Discharge: 0.683 CFS at 11: 00 on Jan 9 in Year 8
Peak Reservoir Stage: 8.04 Ft
Peak Reservoir Elev: 411. 04 Ft
Peak Reservoir Storage: 115252. Cu-Ft
2. 646 Ac-Ft
Add Time Series:bypass.tsf
Peak Summed Discharge: 0.706 CFS at 11:00 on Jan 9 in Year 8
Point of Compliance File:dsoutlev3.tsf
Flow Frequency Analysis
Time Series File:rdoutlev3.tsf
Project Location:Sea-Tac
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks --Rank Return Prob
(CFS) (CFS) (ft) Period
0.475 2 2/09/01 20:00 0.683 8.04 1 100.00 0.990
19737.
19853.
19970.
20087.
20204.
20322.
20439.
20558.
2 0 67 6.
0.103 7 1/07/02 3:00 0.475 7.76 2 25.00 a. 960
0. 396 3 3/06/03 22:00 a. 396 7.25 3 10.00 0.900
0.085 B 8/26/04 7:00 a .263 6.80 4 5.00 0.800
0.105 6 1/08/05 2:00 0.159 5.75 5 3.00 0.667
0.159 5 1/19/06 5:00 0.105 5.25 6 2.00 0.500
0.263 4 11/24/06 9:00 0.103 5.08 7 1. 30 0.231
0.683 1 1/09/08 11:00 0.085 3.38 8 1.10 0.091
Computed Peaks 0.613 8.02 50.00 0.980
Flow Frequency Analysis
Time Series File:dsoutlev3.tsf
Project Location:Sea-Tac
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0. 493 2 2/09/01 19:00 0.706 1 100.00 0.990
0.142 6 1/05/02 16:00 0. 493 2 25.00 0. 960
0.409 3 3/06/03 21: 00 0.409 3 10.00 0.900
0.138 7 8/26/04 2:00 0.283 4 5.00 0.800
0.130 8 1/05/05 8:00 0.159 5 3.00 0.667
0.159 5 1/19/06 5:00 0.142 6 2.00 0.500
0.283 4 11/24/06 6:00 0.138 7 1. 30 0.231
0.706 1 1/09/08 11: 00 0.130 8 1.10 0. 091
Computed Peaks 0.635 50.00 0.980
Flow Duration from Time Series File:rdoutlev3.tsf
Cutoff Count Frequency CDF Exceedence_Probability
CFS % % %
0.007 28877 47.092 47.092 52.908 0.529E+OO
0.020 7017 11.443 58.536 41.464 0.415E+00
0.033 5922 9.658 68.193 31. 807 0.318E+OO
0.047 5531 9. 020 77.213 22.787 0. 228E+OO
0.060 5072 8 .271 85.484 14.516 0.145E+OO
0.073 3690 6.018 91. 502 8.498 0.850E-01
0.087 2268 3.699 95.201 4.799 0.480E-01
0.100 1702 2. 776 97.976 2. 024 0.202E-01
0 .114 837 1. 365 9 9. 341 0.659 0.659E-02
0.127 37 0.060 99.401 0.598 0.598E-02
0.140 17 0.028 99.429 a .sn 0. 571E-02
0.154 26 0.042 99. 472 0.528 0.528E-02
0.167 30 0.049 99.521 0.479 0.479E-02
0.180 45 0.073 99. 5 94 0.406 0.406E-02
0.194 49 0.080 99.674 0.326 0.326E-02
0.207 40 0.065 99.739 0.261 0.261E-02
0.220 26 0.042 99.781 0.219 0.219E-02
0.234 18 0.029 99. 811 0.189 0.189E-02
0.247 18 0.029 99.840 0.160 0.160E-02
0.260 31 0.051 99.891 0.109 0.109E-02
0 .274 13 0. 021 99.912 0.088 0.881E-03
0.287 3 0.005 99.917 0.083 0.832E-03
0.300 2 0.003 99.920 0.080 0.799E-03
0.314 1 0.002 99.922 0.078 0.783E-03
0. 327 1 0.002 99.923 0.077 0.766E-03
0.340 1 0.002 99.925 0.075 0.750E-03
0.354 6 0.010 99.935 0.065 0.652E-03
0.367 6 0.010 99.945 a.ass 0.554E-03
0.380 6 a. 010 99.954 0.046 0.457E-03
0.394
0.407
0.420
0.434
0.447
0.460
0.474
9
3
2
3
3
3
3
0.015
0.005
0.003
0.005
0.005
0.005
0.005
99. 969
99.974
99. 977
99.982
99.987
99.992
99. 997
0.031
0.026
0.023
0.018
0.013
0.008
0.003
0.310E-03
0.261E-03
0.228E-03
0.179E-03
0.130E-03
0.815E-04
0.326E-04
Flow Duration from Time Series File:dsoutlev3.tsf
Cutoff Count Frequency CDF Exceedence_Probability
CFS % % %
0.007 28952 47.215 47.215 52.785 0.528E+OO
0.021
0.035
0.049
0.062
0.076
0.090
0.104
0 .118
0.132
0.146
0.160
0 .173
0.187
0.201
0.215
0.229
0.243
0.257
0.270
0.284
0.298
0.312
0.326
0.340
0.354
0.367
0.381
0.395
0.409
0.423
0.437
0.451
0.464
0. 478
0. 492
7029
5796
5806
4882
3682
2261
1756
642
100
61
32
43
41
43
47
18
16
24
26
8
4
1
3
1
3
4
8
4
9
3
2
3
3
3
3
11. 463
9. 452
9.468
7. 962
6.005
3.687
2.864
1. 04 7
0.163
0.099
0.052
0.070
0.067
0.070
0.077
0.029
0.026
0.039
0.042
0.013
0.007
0.002
0.005
0.002
0.005
0.007
0.013
0. 007
0.015
0.005
0.003
0.005
0.005
0.005
0.005
Duration Comparison Anaylsis
Base File: forest.ts£
58.677
68 .12 9
77.598
85.559
91.564
95.251
98 .115
99.162
99.325
99.424
99. 477
99.547
99.614
99.684
99.760
99.790
99.816
99.855
99.897
99.910
99.917
99.918
99.923
99.925
99.930
99.936
99.949
99.956
99. 971
99.976
99.979
99.984
99.989
99.993
99.998
New File: dsoutlev3.tsf
Cutoff Units: Discharge in CFS
41.323
31.871
22.402
14.441
8.436
4.749
1. 885
0.838
0.675
0. 576
0.523
0.453
0.386
0.316
0.240
0.210
0.184
0.145
0.103
0.090
0.083
0.082
0.077
0.075
0.070
0.064
0.051
0.044
0. 029
0.024
0.021
0.016
0 .011
0.007
0.002
0.413E+OO
0.319E+OO
0.224E+OO
0.144E+OO
0.844E-01
0.475E-01
0.189E-01
0.838E-02
0.675E-02
0.576E-02
0.523E-02
0.453E-02
0.386E-02
0.316E-02
0.240E-02
0.210E-02
0.184E-02
0.145E-02
0.103E-02
0.897E-03
0.832E-03
0.815E-03
0.766E-03
0.750E-03
0.701E-03
0.636E-03
0.506E-03
0.440E-03
0.294E-03
0.245E-03
0.212E-03
0.163E-03
0 .114E-03
0. 652E-04
0.163E-04
Cutoff
0.120
0.152
-----Fraction of Time--------------Check of Tolerance-------
Base New %Change Probability Base New %Change
0.95E-02 0.81E-02 -14.6 I 0.95E-02 0.120 0.114 -5.0
0.63E-02 0.55E-02 -12.7 I 0.63E-02 0.152 0.140 -8.1
0.185 0.50E-02 0.40E-02 -19.1 0.50E-02 0.185 0.168 -9.3
0 .218 0.37E-02 0.23E-02 -37.0 0.37E-02 0. 218 0 .190 -12.5
0.250 0.29E-02 0.17E-02 -41. 7 0.29E-02 0.250 0. 207 -17.1
0.283 0.22E-02 0.91E-03 -58.8 0.22E-02 0. 283 0.225 -20.6
0.316 0.15E-02 0.80E-03 -46. 2 0.15E-02 0.316 0.255 -19.1
0.348 O.lOE-02 0.73E-03 -27.4 O.lOE-02 0.348 0.274 -21. 4
0.381 0. 62E-03 O.SlE-03 -18.4 0.62E-03 0.381 0.370 -2. 9
0.414 0.34E-03 0.26E-03 -23.8 0.34E-03 0.414 0.404 -2. 3
0.446 0.21E-03 0.16E-03 -23.1 0.21E-03 0.446 0. 439 -1. 6
0.479 0.16E-03 0.65E-04 -60.0 0 .16E-03 0.479 0.454 -5.3
0.512 0. llE-03 O.OOE+OO -100.0 0. llE-03 0.512 0. 4 68 -8.6
0.544 0.16E-04 O.OOE+OO -100.0 0 .16E-04 0.544 0. 492 -9.6
There is no positive excursion
Maximum negative excursion= 0. 077 cfs (-22. 4%)
occurring at 0.342 cfs on the Base Data:forest.tsf
and at 0.266 cfs on the New Data:dsoutlev3.tsf
Liberty Gardens -Time Series
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Project Location: Sea-Tac
Computing Series forest.ts£
Regional Scale Factor : 1.00
Data Type: Reduced
Creating Hourly Time Series File
Loading Time Series File:C:\KC_SWDM\KC DATA\STTF60R.rnf
Till Forest 8.64 acres
Total Area 8.64 acres
Peak Discharge: 0.697 CFS at 9:00 on Jan 9 in Year 8
Storing Time Series File:forest.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Loading Stage/Discharge curve:forest.tsf
Flow Frequency Analysis
Time Series File:forest.tsf
Project Location:Sea-Tac
Frequencies & Peaks saved to File:forest.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:forest.tsf
Computing Interval Locations
Computing Flow Durations
Project Location
Durations & Exceedence Probabilities to File:forest.dur
Analysis Tools Conunand
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Sea-Tac
Computing Series dev.tsf
Regional Scale Factor 1.00
Data Type Reduced
Creating Hourly Time Series File
Loading Time Series File:C:\KC SWDM\KC DATA\STTG60R.rnf --Till Grass 3.10 acres
Impervious
Loading Time Series File:C:\KC_SWDM\KC_DATA\STEI60R.rnf
5.29 acres
Total Area 8.39 acres
Peak Discharge: 3.16 CFS at 6:00 on Jan 9 in Year 8
Storing Time Series File:dev.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Loading Stage/Discharge curve:dev.tsf
Flow Frequency Analysis
Time Series File:dev.tsf
Project Location!Sea-Tac
Frequencies & Peaks saved to File:dev.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:dev.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:dev.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
CREATE a new Time Series
Production of Runoff Time Series
Project Location : Sea-Tac
Computing Series bypass.tsf
Regional Scale Factor : 1.00
Data Type ! Reduced
Creating Hourly Time Series File
Impervious
Loading Time Series File:C:\KC SWDM\KC DATA\STEI60R.rnf
0.25 acres
Total Area : 0.25 acres
Peak Discharge: 0.118 CFS at 6:00 on Jan 9 in Year 8
Storing Time Series File:bypass.tsf
Time Series Computed
KCRTS Command
Enter the Analysis TOOLS Module
Analysis Tools Command
Compute PEAKS and Flow Frequencies
Loading Stage/Discharge curve:bypass.tsf
Flow Frequency Analysis
Time Series File:bypass.tsf
Project Location:Sea-Tac
Frequencies & Peaks saved to File:bypass.pks
Analysis Tools Command
Compute Flow DURATION and Exceedence
Loading Time Series File:bypass.tsf
Computing Interval Locations
Computing Flow Durations
Durations & Exceedence Probabilities to File:bypass.dur
Analysis Tools Command
RETURN to Previous Menu
KCRTS Command
eXit KCRTS Program
Liberty Gardens -Peak Flow Rates
Flow Frequency Analysis
Time Series File:forest.tsf
Project Location:Sea-Tac
---Annual Peak Flow Rates---
Flow Rate Rank Time of Peak
(CFS)
0.545 2 2/09/01 18:00
0.148 7 1/06/02 3:00
0.404 4 2/28/03 3:00
0.014 8 3/24/04 20:00
0.240 6 1/05/05 8:00
0.418 3 1/18/06 21: 00
0.353 5 11/24/06 4:00
0.697 1 1/09/08 9:00
Computed Peaks
Flow Frequency Analysis
Time Series File:dev.tsf
Project Location:Sea-Tac
---Annual Peak Flow Rates---
Flow Rate Rank Time of Peak
(CFS)
1. 56 6 2/09/01 2:00
1. 27 8 1/05/02 16:00
1. 88 3 2/27/03 7:00
1.38 7 8/26/04 2:00
1. 66 4 10/28/04 16:00
1. 65 5 1/18/06 16:00
2.00 2 10/26/06 0:00
3.15 1 1/09/08 6:00
Computed Peaks
Flow Frequency Analysis
Time Series File:rdoutlev3.tsf
Project Location:Sea-Tac
---Annual Peak Flow Rates---
Flow Rate Rank Time of Peak
(CFS)
0.475 2 2/09/01 20:00
0.103 7 1/07/02 3:00
0. 396 3 3/06/03 22:00
0.085 8 8/26/04 7:00
0.105 6 1/08/05 2:00
0.159 5 1/19/06 5:00
0.263 4 11/24/06 9:00
0.683 1 1/09/08 11 :OD
Computed Peaks
-----Flow Frequency Analysis-------
--Peaks Rank Return Prob
(CFS) Period
0.697 1 100.00 0.990
0.545 2 25.00 0.960
0.418 3 10.00 0.900
0. 404 4 5.00 0.800
0.353 5 3.00 0.667
0.240 6 2.00 0.500
0.148 7 1. 30 0.231
0.014 8 1.10 0.091
0.646 50.00 0.980
-----Flow Frequency Analysis-------
--Peaks Rank Return Prob
(CFS) Period
3.15 1 100.00 0.990
2.00 2 25.00 0. 960
1. 88 3 10.00 0.900
1. 66 4 5.00 0.800
1. 65 5 3.00 0.667
1. 56 6 2.00 0.500
1. 38 7 1. 30 0.231
1. 27 8 1.10 0.091
2.77 50.00 0.980
-----Flow Frequency Analysis-------
--Peaks --Rank Return Prob
(CFS) (ft) Period
0.683 8.04 1 100.00 0.990
0.475 7.76 2 25.00 0.960
0. 396 7.25 3 10.00 0.900
0.263 6.80 4 5.00 0.800
0.159 5.75 5 3.00 0.667
0.105 5.25 6 2.00 0.500
0 .103 5.08 7 1. 30 0.231
0.085 3.38 8 1.10 0.091
0. 613 8.02 50.00 0.980
Flow Frequency Analysis
Time Series File:dsoutlev3.tsf
Project Location:Sea-Tac
---Annual Peak Flow Rates--------Flow Frequency Analysis-------
Flow Rate Rank Time of Peak --Peaks Rank Return Prob
(CFS) (CFS) Period
0.493 2 2/09/01 19:00 0.706 1 100.00 0.990
0.142 6 1/05/02 16: 00 0. 4 93 2 25.00 0. 960
0.409 3 3/06/03 21:00 0.409 3 10.00 0.900
0.138 7 8/26/04 2:00 0.283 4 5.00 0.800
0 .130 8 1/05/05 8:00 0.159 5 3.00 0. 667
0.159 5 1/19/06 5:00 0.142 6 2.00 0.500
0.283 4 11/24/06 6:00 0.138 7 1. 30 0.231
0.706 1 1/09/08 11: 00 0.130 8 1.10 0.091
Computed Peaks 0.635 50.00 0.980
0.8
--+--Existing R -Developed
0.7
0.6
.;; 0.5 -. 11. ;;
~ ,· ., ~ 1. 0.4
Ci::
~ ;:;:
0.3
0.2
0.1 -~ •:i
" fl ,, -~
0
1.00E-05 1.00E-04 1.00E-03 1.00E-02 1.00E-01 1.00E+OO
Probability of Exceedence
Flow Duration Curves for RID. Duration curves are shown at a downstream point-
of-compliance to account for a small amount of bypass. Tbe pond is designed to meet
Level 3 flow control standards.
STATE OF WASHINGTON, COUNTY OF KING }
AFFIDAVIT OF PUBLICATION
PUBLIC NOTICE
Linda M Mills, being first duly sworn on oath that she is the Legal
Advertising Representative of the
Renton Reporter
a weekly newspaper, which newspaper is a legal newspaper of
general circulation and is now and has been for more than six months
prior to the date of publication hereinafter referred to, published in
the English language continuously as a weekly newspaper in King
County, Washington. The Renton Repo1ter has been approved as
a Legal Newspaper by order of the Superior Court of the State of
Washington for King County.
The notice in the exact form annexed was published in regular issues
of the Renton Reporter (and not in supplement form) which was
regularly distributed to its subscribers during the below stated period.
The annexed notice, a:
Public Notice
was published on May 27, 2011.
The full amount of the fee charged for said foregoing publication is
the sum oC$84.00.
//
' 'g,I Notary PublicA%r the State of Washington, Residing
in Coving'ttm, Washington
P. 0. Number:
NOTICE OF
APPEAL HEARI~G
RE'\TON HEARING
EXAMINER
RENTOI\, WASHINGTON
An arpeal Hearing will be held
by the Renton Hearing Examiner
in the Council Chambers on the
seventh floor of Renton City
Hall, 1055 South Grady Way,
Renton, Washington, on June 13,
2011 at 9:00 a.m. to consider the
following petitions
Liberty Gardens Modified
Preliminary Plat Appeal
LUA08-093
Location. SE of 162nd St SF
and SE 140th St. Appeal of En -
vironmcntal Review threshold
DNS-Mitigated Proposal is to
subdivide an 8.95 acre site mto
46 sin!!le family lots
The -public· hearing for the
modification lO the Liberty
Gardens Preliminary Plat will be
heard immediately followmg the
appeal hearing.!.egal descriptions
of the files noted above are on
file in the City Clerk's Office.
Seventh Floor. City Hall. Renton.
All interested persons arc invited
to be present al the Public Hear-
ing to express their opinions
Questions should be directed Lo
the Hearing Examiner at 425-
430-6515
Publshed in the Renton Reporter
on May 27. 201 !.# 492940
2009.03.11
To Whom It May Concern:
CARE -Community Alliance to Reach Out & Engage
P.O. Box 2936
Renton. WA 98056
highlands_neighbors@hotmail.com
206.888.7152
CITY OF RENTON . "'
L-'' ,.-. \} ,· " ' MAR 11 2009 ,'
R.ECEIVED
CITY CLERK'S OFFICE
The following package is the CARE Response: Liberty Gardens LUAOB-093 for SEPA Appeal and Preliminary Plat
Hearing 3/17/08. The only differences between this hardcopy package and the electronic version emailed to the parties on
March 10, 2009 is that this one contains the full Addenda of additional documentation we submit for the record and
corrections (removed duplicate listings and added one document) to the Proposed New Exhibits List. No other content
changes have been made.
Upon initial reading of the staff prepared Preliminary Report to the Hearing Examiner in this manner, it appears that CARE
will need to make some amendments to the content of the record of our concerns at the Hearing in light of the new
information now available in the Preliminary Report. These amendments are anticipated to be substantive only in light of
the concerns that may be relieved in light of the staff recommendations, should they be affirmed and applied by the
Hearing Examiner.
If there are errors of fact or argument within our Response presentation, we look forward to correction at the Public
Hearing scheduled for March 17, 2009.
Please contact me with any comments.
Thank you,
~!/4f~;11,_, -(~ f.
-Gwendolyn High
president
CARE Response: Liberty Gardens LUA08-093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
Introduction
Since November 2001. Community Alliance to Reach Out & Engage (CARE). a Washington State non-profit corporation
representing over 500 households in the East Renton Plateau Potential Annexation Area, has been meeting with and
recording the concerns of the residents impacted by ongoing development activity in our community. We have an
established record of acting as a conduit for the valid concerns of owners and residents of this community to the elected
officials and departments of the government entities who hold jurisdiction here.
Gwendolyn High, our president, will represent CARE in this matter. Ms. High is a data analyst, programmer and
information technology project manager. She is co-founder and current president of CARE and has led CARE's previous
efforts as Intervenor in the in the matters of the Plat Applications for the Evendell (KC ODES file No. LD1 P0016 and
L01TY401). Liberty Grove (KC DOES file No. L03P0006/L03TY403). Liberty Grove Contiguous (KC DOES file No.
L03P0005/L03TY401). Nichols Place (KC DOES file No. L03P0015), Threadgill (KC ODES file No. L05P0026) and
Heritage (KC DOES file No. L07P0009) subdivision projects. Though she currently serves as a Renton Planning
Commissioner. her participation in these matters is entirely independent of that role.
Debi Eberle will assist in proceedings in this matter. Ms. Eberle is our vice president. She is also a Washington State
University King County Extension Watershed Steward and serves on the board of the Washington Land and Water
Steward Association.
CARE households own properties and reside in the community surrounding the proposed subdivision development. These
owners/residents would be directly and adversely affected if the subject application is permitted and constructed according
to the current proposal. CARE and its participant households are intensely concerned with protecting against physical
damage to existing residences and properties as a result of site preparation, construction. and use associated with this
development. Recent developments in the area have resulted in tens of thousands of dollars of damage to surrounding
properties and incalculable heartache. Such impacts would harm these community members' interests in protecting their
property values, along with their privacy and the quiet enjoyment of their property.
CARE's participation in this matter is in the public interest. We are primarily interested in ensuring coordinated and
responsible development of the community consistent with state and local laws and regulations. We bring historical
experience and familiarity with the existing conditions of our community as well as the detailed understanding of the
probable negative impacts that must be adequately mitigated. We provide documentation and evidence of the existing
circumstances and context in which this project site is located. Our intent is to facilitate the appropriately thorough
consideration of the facts that bear on this proposed project.
We intend and request that any issue that might otherwise be excluded from consideration because of our inadvertent
presentation out of its proper place (during the SE PA Appeal portion of the Hearing where is should be presented during
the Plat Hearing phase or vis versa). shall be considered to be part of of the concerns we present as a whole and given
appropriate weight under the correct heading.
In this Response, we will present quotation/reference of documents followed by discussion and request for relief in the
balance of this document. Most quotations/references are of/to documents already in the public/staff file for this
applications. Additionally, we submit these new documents and excerpts of some existing documents for easy reference
as addenda to this document.
Page I Of 27
CARE Response: Liberty Gardens LUA08-093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
Proposed New Exhibits List
DocName Date Time Author Finn
Letter:RE: Liberty Gardens, 03/03108 Ed McCarthy PE PS Ed McCarthy PE PS
Cavalla Development and
Threadgill Plat Recommended
Stormwater Mitigations (excerpt(s))
Report: SE 1441" Street Level 3 6/16107 Ed McCarthy PE PS Ed McCarthy PE PS
Downstream Analysis for
Threadgill, Cavalla and Liberty
Gardens (excerpt(s))
, Email: RE: Level 3 Offsite Analysis Bruce Whittaker KC DOES
Addendum0ct12,2007
'Email:Drainage Bypass Proposal 09126/07 David Petrie David Petrie
. Report: Liberty Gardens Critical 11119104 Ed Sewell and Darcey B-12 Wetland Consulting Inc
Areas Analysis Report & B. Miller
Conceptual Mitigation Plan
(excerp1(s))
Letter: RE: Resubmittal of 11122106 G. Wayne Potter Barghausen Consulting Engineers
Additional Information and/or
Studies Preliminary Plat of Liberty
Gardens (excerpt(s))
Report: Conceptual Wetlands · 05116107 Chad Armour Chad Armour, LLC
Mitigation Plan (revised) Liberty
Gardens (excerpt(s))
Report: Conceptual Wetlands 05116107 Chad Armour Chad Armour, LLC
Mitigation Plan 162·'d Avenue SE -
Proposed Extension (excerpt(s))
CARE Surveys: Drainage Circulated Gwendolyn High 'CARE
Questions for Neighbors Adjacent 711112008
to and/or Downstream of Liberty
Gardens
Email: Ritchey Note 12116107 Mike Ritchey Resident
Email: Liberty Gardens 911 7108 Gwendolyn High ·CARE
Email: RE: Urgent-Arterial 02/11/2008 Kristen Langley KC DOT
Review
Email: 12116107 7:04p 1.l!lllb~~·illl ~~Ill Resident
m
' April 2008 15am Ave SE traffic 418108 KC DOT
report File# 08-9143
' Cavalla L06P0001 -Rescreening 01108107 Bruce Whittaker KC ODES
, Comments
Email:Cavalla Undated Bruce Whittaker KC DOES
L06P0001 :Rescreening Issues
Email: RE: L06P0001 712612007 · 1:25pm · Nick Gillen KC ODES
Email:Re: Cavalla Plat L06P0001 712512007 9:49 Kristen Langley KC ODES
am
Email: RE: Public Disclosure : 02/25108 9:18 Kristen Langley KC DOT
Request: ODES File Numbers AM
· L04P0034 and L06P001
Emait:RE: Public Disclosure 02/28/08 Kristen Langley KC DOT
Request: DOES File Numbers
L04P0034 and L06P001
Email: RE: Public Disclosure 03104108 05:04: Matthew Nolan KC DOT
Request: ODES File Numbers OOAM
L04P0034 and L06P001
Notes: Cavalla Re-screening 04115/08 , Bruce Whittaker KC DOES
KC Transportation Needs Report KCDOT
2008
1 CARE Annotated Assessor's Map Gwendolyn High CARE
Page:?: Of 27
CARE Response: Liberty Gardens LUAOS-093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
Drainage
DocName Date
Letter:RE: Liberty Gardens, 03/03/08
Cavalla Development and
Threadgill Plat
Recommended Stormwater
Mitigations
Time Author Firm Page Para
Ed McCarthy PE Ed McCarthy PE PS 2 3
PS
"I conducted KCRTS simulations for the Cava Ila and Liberty Garens plats to estimate the stormwater detention
volumes that would be required to meet Level 3 flow control standards (Attachment C), For Cavalla, I estimated
a required storage volume of 132,300 cubic feet. For Liberty Gardens, I estimated a required storage volume of
114,600 cubic feet. These estimated volumes do not include a factor of safety which would increase the
required volumes, nor do they account for the effects of required flow control BMPs, which would reduce the
required storage volume ... "
Mr McCarthy did not recalculate the required storage volume for the proposed vault in the 162°' Ave SE ROW (under the
proposed extension of 162'' Ave SE). New analysis is necessary and must be required.
DocName
Report: SE 144'h Street
Level 3 Downstream
Analysis for Threadgill,
Cavalla and Liberty
· Gardens
Date
6/16/07
Time Author Firm
Ed McCarthy PE Ed McCarthy PE PS
PS
Page Para
2-8 3 and
bullets
"Roadway flooding along SE 144'h Street would be considered as "severe roadway flooding problem" according
to the King County standards (King County DNRP, January 2005) due to the following conditions:
• Between the intersection of 162" Avenue SE and 160'h Avenue SE driveway culverts along the ditch on
the north side of SE 144'h Street would be overtopped. posing a threat of unsafe access due to
indiscernible driveway edges.
• Floodwater over the driveways on the north side of SE 144'' Street between 160'" Ave SE and CB-11A
would be deeper than 0.5 foot, posing a severe impediment to emergency vehicle access.
Doc Name Date Time Author Firm Page Para
Letter RE Liberty 03/03/08 Ed McCarthy PE Ed McCarthy PE PS 1 3
Gardens, Cavalla .PS
Development and
Threadgill Plat
Recommended Stormwater
Mitigations
"The presence of flooding driveway culverts would not create unreasonable difficulties for emergency access to
the residences.'
These two descriptions are completely contradictory. The assertion that the photos indicates new data on which to base
this new opinion is not supported once the actual photos are inspected. The photos show neither flooding nor sufficient
context by which to revise the evaluation (edges of drive surfaces or ditch to drive surface elevation changes). Certainly
the candid snap shots can not outweigh the hydrological modeling underlying the original analysis. Perhaps the next
documents cast light on the change of characterization.
DocName
Email: RE: Level 3 Offsite
Analysis Addendum Oct 12,
2007
Date Time Author Firm Page Para
Bruce Whittaker KC DOES
Exchanges between Mr. Petrie and Mr. McCarthy between 9/24/07 and 9/27/07. Mr. Petrie persuades Mr.
Page 3 Of27
CARE Response: Liberty Gardens LUA08-093 for $EPA Appeal and Preliminary Plat Hearing 3/17/08
McCarthy to change professional opinions previously submitted to KC staff with the promise of pay for services
rendered.
DocName
Email:Drainage Bypass
Proposal
Date
09/26/07
Time Author
David Petrie
Firm Page Para
David Petrie 1 1
"Page two, listing " -issues of concern" could be easily modified with an optimistic flavor without losing
content."
Doubt is cast on all of the work submitted by the otherwise well regarded Mr. McCarthy. Inconsistencies in materials
submitted by him must be held to increased scrutiny, particularly when the safety and property of the public is at stake.
DocName Date Time · Author Firm Page 'Para
Letter: RE: Liberty 03/03/08 'Ed McCarthy PE Ed McCarthy PE PS 3 , last
Gardens, Cavalla PS
Development and
Threadgill Plat
Recommended Stormwater
Mitigations
[offers recommendations to fix outstanding drainage issues to the adjacent properties on SE 142"' Place via
stormwater conveyance upgrade and connection of the Gragg property to sewer] " ... Please note that the
applicants for the proposed plats willingly off the mitigations that would benefit the property owners along SE
142'" Place provided that the mitigations can be designed and implemented without incurring unreasonable
delays that may be confronted in acquiring construction easements, permits and other construction-related
authorizations."
Basically, the applicant proposes to do the right thing if it does not cause any delay. Considering the track record of this
application in terms of timely and complete application materials, this is an unreasonable risk to the affected property
owners and a virtual guarantee that the proposed improvements will never occur unless required outright as a condition of
the plat application. Relief for the residents/owners of the SE 142"' Place properties must be required for approval of this
application.
, DocName
Report: Liberty Gardens
Critical Areas Analysis
Report & Conceptual
Mitigation Plan
Date
11/19/04
Time , Author
. Ed Sewell and
Darcey B. Miller
Finm
8-12 Wetland
Consulting Inc
Page Para
1 4
"Ed Sewell of B-twelve marked the wetland edges and the centerline of the stream on site on September 12,
2001. Darcey Miller verified the delineation on September 28, 2004."
Site visit at end of water year (driest possible time) in both cases. In light of extensive wetlands and streams, site review
under other than ideal conditions is only reasonable.
DocName Date
Letter: RE: Resubmittal of 11/22/06
Additional Information and/
or Studies Preliminary Plat
of Liberty Gardens
Time Author Firm
G. Wayne Potter · Barghausen
: Consulting Engineers
Page
4
Para
: [KC staff request for additional information from 5/24/05] " ... flagging for Wetland C is no longer there. Wetland C
will need to be re-flagged and verified ... "
'[Barghausen response] " ... A report on the impacts of Liberty Gardens frontage improvements is being prepared
by Chad Armour, LLC and will be submitted under separate cover letter ... "
Page 4 Of 27
CARE Response: Liberty Gardens LUAOS-093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
DocName Date
Report: Conceptual 05/16/07
Wetlands Mitigation Plan
(revised) Liberty Gardens
DocName
Report: Conceptual
Wetlands Mitigation Plan
162°d Avenue SE -
Proposed Extension
Date
05/16/07
Time Author Firm Page Para
Chad Armour Chad Armour, LLC
Time Author Firm Page Para
Chad Armour Chad Armour, LLC
No record or other indication that Wetland C was ever reflagged or verified, Re/lagging and verification is necessary and
must be required,
DocName
Report: Liberty Gardens
: Critical Areas Analysis
, Report & Conceptual
Mitigation Plan
Date
11/19/04
Time Author Firm Page Para
Ed Sewell and B-12 Wetland 6 Section
Darcey 8, Miller Consulting Inc 5,1
Description of the 20' roadway bridge originally proposed to cross the stream for the proposed extension of
162"' Ave SE,
DocName
Cava/la L06P0001 -
Rescreening Comments
"22' width not wide enough
can't grade into stream
Date
01/08/07
needs reasonable use approval"
Time Author 'Firm
Bruce Whittaker KC DOES
Page Para
Critical
Areas
Not only did KC staff change the roadway width to a minimum of 22 feet, but the stream was to be culverted -not bridged.
Even as proposed here, the retaining walls shown on plans for the eastern side, but not the western side, so the required
6' gravel shoulder will be graded into and impact the wetland/stream buffer on the western side. Also, note KC staff's note
that grading into a stream is forbidden.
This wetland mitigation proposal is utterly obsolete. A new and complete analysis is necessary and must be required.
DocName
Report: Liberty Gardens
Critical Areas Analysis
Report & Conceptual
Mitigation Plan
Date
11/19/04
Time Author
Ed Sewell and
Darcey B. Miller
Firm
B-12 Wetland
Consulting Inc
Page Para
6 last
"The mitigation opportunities on site are very limited, as the maJority of the site is densely forested.
DocName Date Time Author Firm Page Para
Report: Conceptual 05/16107 Chad Armour Chad Armour, LLC
Wetlands Mitigation Plan
(revised) Liberty Gardens
"As you will recall, we chose the fee-in-lieu option to mitigate for the unavrndable impacts to wetlands because
the area available on the site for mitigation is the location of a mature forest."
DocName Date Time Author Firm Page Para
Page 5 Of 27
CARE Response: Liberty Gardens LUAOB-093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
Report: Conceptual
Wetlands Mitigation Plan
162" Avenue SE -
Proposed Extension
05/16/07 Chad Amnour Chad Armour, LLC
"We also understand that because there is not enough area available on site to make up for unavoidable
impacts, additional mitigation will use the Mitigation Reserves Program."
---------
Since this site has been annexed into the City of Renton, the King County Mitigation Reserves Program is no longer
available for fee-in-lieu of mitigation.
Much has changed since this report submitted. Current preliminary plat map shows greatly increased impacts to streams
and buffers. This report does not consider tightlining the stream in the 162nd Ave SE ROW as currently proposed. The
tree retention/replacement calculations from 11/6/06 Tree Retention Plan do not match the plans received 5/2/08. Both
attempt to take credit for retaining an off-site tree.
DocName
CARE Surveys: Drainage
Questions for Neighbors
Adjacent to and/or
Downstream of Liberty
Gardens
Date
Circulated
7/11/2008
Time Author
Gwendolyn High
Firm
CARE
Page : Para
Richard and Teri Langdon -14201 164'h Ave SE: Severe flooding (inside home/crawlspace) and extensive
drainage improvements
DocName
Email: Ritchey Note
Date
12/16/07
Time Author
Mike Ritchey
Firm
Resident
[email submitted for the Threadgill application, but the facts are relevant]
Page , Para
" ... We live at 14225 164th Ave SE to the south of the Liberty ball fields. There is 5 acres to our north that they
want to develop and we are very concerned for traffic and water run off. A number of years ago they made an
attempt to develop the acreage and in doing so caused the water flows to change and ourselves and neighbors
had water under our homes. None had water prior to the skinning of the lots ... "
Surface water runoff from the Liberty Gardens site already causes significant impacts to adjacenUdownstream property
owners.
: DocName
Email: Liberty Gardens
Date
9/1 7/08
Time Author Firm : Page Para
Gwendolyn High CARE
CARE documented the existence of a stream exiting the Liberty Gardens site at the southeast corner not
previously disclosed by any materials submitted by the applicant.
None of the materials submitted by the applicant acknowledges any drainage issues from the southeastern corner of the
site, yet considerable evidence and testimony indicates otherwise. New drainage analysis is necessary and must be
required.
TrafficfTransportation
'DocName
: CARE Surveys:
· TrafficfTransportation
Questions for Residents
Affected by Liberty
Gardens
Date
Circulated
7/11/2008
Time Author Firm
Gwendolyn High CARE
Page Para
1-8
Page 6 Of '27
CARE Response: Liberty Gardens LUA08-093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
DocName
Email: Ritchey Note
Date
12/16/07
Time Author
Mike Ritchey
Firm
Resident
[email submitted for the Threadgill application. but the facts are relevant]
" ... We live at 14225164thAve SE to the south of the Liberty ball fields ..
Page Para
We are also very concerned about pushing 164th Ave SE through and the increased amount of traffic. We
have lived in our home since we built it in 1990. We get a lot of traffic during the ball season when people park
and walk into the Liberty ball fields. The parking in front of our home and neighbors leads to the dumping of
ash trays, garbage and the blocking of the mail boxes for deliveries. "
The residents surrounding the proposed project site are very concerned about traffic impacts.
DocName
Report: Traffic Impact
Analysys for
Threadgill/Cavalla/Liberty
Gardens
Written 10/31/2006
Date
10/31/2006
Time Author
Gary A. Norris,
PE PTOE
Firm Page Para
DN Traffic Consultants Cover
It was submitted over two years ago. and the underlying data on which it relies is even older.
DocName
Report: Traffic Impact
Analysys for
Threadgill/Cavalla/Liberty
Gardens
Date
10/31/2006
"The plat of Cavalla is proposed for 34 lots."
Time Author
Gary A. Norris,
PE PTOE
:Firm Page Para
· DN Traffic Consultants 1 last
Cavalla is now proposed for at least 36 lots and the possibility of the use of Transfer of Development Right density
bonuses has been under discussion which could raise the total number of units to as many as 50.
DocName
Report: Traffic Impact
Analysys for
Threadgill/Cavalla/Liberty
Gardens
Threadgill site plan
Date
10/31/2006
Time Author
Gary A. Norris,
PE PTOE
Firm Page Para
DN Traffic Consultants Figure
2
The Threadgill site plan is now longer as represented in this TIA. The recorded site plan is obsolete.
DocName
Report: Traffic Impact
Analysys for
ThreadgilllCavalla/Liberty
Gardens
Cavalla site plan
Date
10/31/2006
Time Author
Gary A. Norris,
PE PTOE
Firm Page Para
DN Traffic Consultants Figure
3
The Cavalla site plan is now longer as represented in this TIA. The recorded site plan is obsolete.
This TIA is based on original site plans for the related Threadgill and Cavalla projects which Jointly propose construction of
162'd Ave SE to intersect with SE 144'h St. Both of those projects have been redesigned, yet the changes in traffic impacts
have never been reevaluated.
Page 7 Of '27
CARE Response: Liberty Gardens LUA08·093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
DocName
Report: Traffic Impact
Analysys for
Threadgill/Cavalla/Liberty
Gardens
Date Time Author
10/31/2006 Gary A. Norris,
PE PTOE
Firm , Page Para
ON Traffic Consultants 4 3
"All three plats are expected to be fully occupied by 2008, which for the purposes of this analysis is assumed to
be the horizon year."
Construction has not begun on any of the three proposed projects. Another critical technical assumption upon which the
traffic impact analysis depends is obsolete.
, DocName Date Time Author Firm Page Para
Report: Traffic Impact 10/31/2006 Gary A. Norris, ON Traffic Consultants 4 last
Analysys for PE PTOE
Threadgill/Cavalla/Liberty
Gardens
"160th AVE SE is a two-lane neighborhood collector ... "
DocName Date Time .Author Firm Page 'Para
Report: Traffic Impact 10/31/2006 Gary A. Norris, · ON Traffic Consultants 7 2
Analysys for PE PTOE
Threadgill/Cavalla/Liberty
Gardens
"SE 136th ST, in the vicinity of the plat. is a two-way local access street"
DocName Date Time , Author Firm Page Para
Email: RE: Urgent -Arterial 02/11/2008 Kristen Langley KC DOT
Review
SE 136th St and 150• Ave SE are proposed to be reclassified as arterials
Major access roads for the site are incorrectly characterized by the TIA. SE 136'h St and 150• Ave SE were proposed to
be reclassified as arterials in the most recent Functional Arterial Reclassification update to the King County
Comprehensive Plan, but all the the SE 136'h St segment and most of the 160" Ave SE segment under discussion were
annexed into the City of Renton with the August 11, 2008 Liberty Annexation and thus were excluded from the 2008 King
County Comp Plan update. Nonetheless, the actual circumstances of the transportation infrastructure to be impacted by
the proposed plat are incorrectly represented in the TIA.
CARE participated as official recognized Intervenor before the King County Hearing Examiner for the Evendell, Nichols
Place, Liberty Grove, Liberty Grove Contiguous, and Threadgill plats. In each of these decisions, traffic mitigations
required by King County have proven insufficient within five years of first occupancy of these projects (some are still under
construction -so they can not have yet had an impact on area intersections). Construction of SE 136'h ST to Subcollector
Street (Urban) Standard between 160" AVE SE and 155• AVE SE was required, but already it has already been proposed
to be reclassified as a Collector Arterial. Improvements to 1 so• AVE SE were also required to the Subcollector Street
(Urban) Standard, and again it has already been proposed to be reclassified as a Collector Arterial. During the Evendell
hearing, CARE asked for stop signs at the intersection of SE 136'' St and 158" Ave SE. We were assured that mitigation
recommendations were more than adequate. Stop signs at the corner of SE 136" St and 158'h AVE SE have now been
installed due to high speed, high volume and accidents from the beginning occupation of the Evendell project. "No
Parking" signs have also been recently installed at this intersection due to poor sight lines contributing greater danger to
the above listed issues. Additionally, the intersection of SE 136'h St and 156• AVE SE was constructed as an alternative to
the identified need for improvements to the HAL intersection of SE 128'h St and 160'h AVE SE. This new intersection
debuted with an LOS F and continues to be a very dangerous intersection and a grave concern to the community. The
sentiment in the community that a brand new dangers are being created with these sub-standard new intersections
instead of improvements to known dangers being required can be described as nothing other than outrage.
Page 8 Of 27
CARE Response: Liberty Gardens LUAOS-093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
DocName
Report: Traffic Impact
Analysys for
Threadgill/Cavalla/Liberty
Gardens
Date
10131 /2006
Time Author
Gary A. Norris,
PE PTOE
Firm Page Para
DN Traffic Consultants 7 Last
"The existing AM and PM peak hour traffic volumes at the analysis intersections was determined from AM and
PM peak period turning movement counts collected during Oct 2006."
DocName Date Time Author Firm
Report: Traffic Impact 10/31/2006 Gary A. Norris, DN Traffic Consultants
Analysys for PE PTOE
Threadgill/Cavalla/Liberty
Gardens
"2008 Without ProJect Level of Service"
DocName Date Time Author Firm
Report: Traffic Impact 10/3112006 Gary A. Norris, DN Traffic Consultants
Analysys for PE PTOE
· Threadgill/Cavalla/Liberty
Gardens
"156th AVE SEISE 136th St -Zero accidents in the 3 year analysis period"
DocName
Email:
Date
12/16107
Time Author Firm
7 04p smlth5124@aim c Resident
m Qm
Page Para
10 Table
2
Page Para
12 Table
3
Page Para
" ... I was hit at the intersection 01136th and 158'h .. that was Jan. 3" before the stop signs were put up on 136'h.
We were almost hit there again last week ... "
The traffic counts recorded are prior to lull occupation of the Evendell, Nichol's Place, Liberty Grove and Liberty Grove
Contiguous projects. The "3 year analysis period" was prior to the construction of SE 136" St between 156'h Ave SE and
160'h Ave SE. There was no street, so there were no accidents. The last house at Evendell was not occupied until late
2008, and Liberty Grove and Liberty Grove Contiguous are still under construction today.
·DocName
Report: Traffic Impact
Analysys for
Threadgill/Cavalla/Liberty
Gardens
Date Time . Author
10/31/2006 Gary A. Norris,
PE PTOE
Firm Page Para
DN Traffic Consultants 15 Trip
Distrib
ution
" ... northbound traffic on 160th Avenue SE destined westbound on SE 128'h Street is expected to head west on
SE 136'h St to access the signal at the 156" Avenue SE/SE 128'h Street intersection rather than head north on
160"· Ave SE ... "
DocName Date Time Author Firm Page Para
April 2008 158'h Ave SE 418/08 KC DOT
traffic report File# 08-9143
Despite assertions to the contrary for this, Evendell and other projects made by this consultant. people do take 160th Ave
SE and 158th and Ave SE instead of SE 136th St to get to SE 128th St. The heavy volumes and high speeds are further
documented in the above referenced proposal for functional arterial reclassification.
Page 9 Of 27
CARE Response: Liberty Gardens LUA08-093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
On several aspects of the proposed project, King County staff has echoed our concerns in internal communications, yet
failed to address these concerns in any of their recommend mitigations. In fact, King County entered a SEPA
Determination of Non Significance for the Liberty Gardens proposal which Renton subsequently rescinded as
inadequate/inappropriate.
DocName
Cavalla L06P0001 -
Rescreening Comments
"22' width not wide enough
can't grade into stream
Date
01/08/07
needs reasonable use approval"
Time Author Firm Page Para
Bruce Whittaker KC ODES 1 Critical
Areas
22' width for the proposed extension of 162" Ave SE is all that KC staff ever recommended or that applicant ever
proposed despite the fact that such narrow width is acknowledged to be inadequate mitigate the impacts of the new plats
and thus is a violation of the King County Roads Standards.
. DocName
Email:Cavalla
L06P0001 :Rescreening
Issues
Date
Undated
Time Author Firm
Bruce Whittaker KC ODES
" ... the whole subdivision feasibility may not work unless Nick [Gillen] agrees to mitigation ... "
Page Para
1
There is no documentation of increased drainage mitigation to address the impacts of the proposed extension of 162" SE
through the wetlands and streams.
DocName
: Email: RE: L06P0001
Date Time Author
7/26/2007 1:25p Nick Gillen
m
'Firm • Page Para
,KC DOES 1
" ... It was my understanding that we are going to ask for a revision (road built to road standards) ... "
KC Staff again acknowledges that changes to the originally proposed extension of 162" Ave SE did not meet the King
County Road Standards, yet the applicant has never submitted any revisions to the original plans.
DocName Date !Time Author Firm Page : Para
Email:Re: Cavalla Plat 7/25/2007 ; 9:49 Kristen Langley KC DOES 1 From
L06P0001 .am . Steve
i Foley
" ... if the county were to consider a capital project on SE 144•, the size, cost and complexity suggest that wit
would probably take years for it to be built. .. lf we were to do a CIP here it looks like it would be a large CIP, not
a NDAP. Some more limited downstream improvement by the developers might make sense than an uncertain
KC project. I tend to favor a downstream fix if feasible rather than just doing Level 3 flow control.'
No staff could be more knowledgeable than Mr. Foley in regard to the the intent and letter of the King County Drainage
Manual, as he is a principle author of that standard. His analysis points out that there is a systemic inadequacy in the
drainage conveyance systems downstream of Liberty Gardens and that even Level 3 flow control is inadequate to mitigate
the expected impacts. Nonetheless, DOES staff failed to recommend any additional mitigation and the applicant failed to
propose any. The unusual and historically problematic hydrological/drainage circumstances in which this site is located
are well documented and fully support the additional drainage mitigation requirements that Renton staff has required via
the newly issued SEPA MONS.
: DocName Date Time , Author Firm Page Para
9: 18 Kristen Langley
AM
KC DOT · Email RE Public 02/25/08
· Disclosure Request: DOES
1 4
Page JO Of 27
CARE Response: Liberty Gardens LUA08~093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
File Numbers L04P0034
and L06P001
"The alignment proposed by Barghausen, with this first submittal, has a sag vertical curve shortly before its
intersection with SE 144" that may be shorter than KCRS in order to provide a KC RS-compliant intersection
landing."
KC staff says that it is virtually impossible for both the intersection landing and the sag vertical curve standards to both be
met at this location. In order to meet one standard, the other must be sacrificed. This is grossly inappropriate from a safety
point of view.
Doc Name Date
Email RE Public 02/25/08
Disclosure Request: ODES
File Numbers L04P0034
and L06P001
Time Author
09:18 Kristen Langley
:DO
AM
Firm Page Para
KC DOT 1 5
" ... these off-site improvements have to have a minimum of 22-feet paved width, curb/gutter/sidewalk on one
[east] side (for pedestrians and to control stormwater). The half-street standard is limited to serving as primary
· access to "35 lots", and in my assessment has come up to approximately 40-45 trip ends use the off-site
section of the roadway in the PM peak hour."
From the King County Roads Standards:
Page II Of27
CARE Response: Liberty Gardens LUA08-093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
2.03(8) Urban Local Access Roadways· (Curb Roadway Section)
Classification Neighborhood Subcollectors Sub access Mi nor Ace es s
Collectors
Access Restricted, Lots front As needed with SUbaccess streets are Permanent cul-de-sacs
on local access street some restrictions.' not suPPortive of or short loops wilh low
where feasible. through traffic. traffic volumes !hat
Generally permanent provide mculation and
cul-de-sacs er short access to off-slreel
loop' slreets Iha! parlling within
I connect to residential development
subcollectors. limits.
Public or Private Public StreelS Public Streets Public Streets Public or Privale (See
Section 2.06)
.
Serving Potential Number of Over 101}' I 100 Maximum• I 50 Maximum 16 Maximum
Lots or Dwelling Units
Design Speed 5 35mph 30 mph Low Speed Curve Low Speed Curve (See
(See Section 2.10) Section 2.10)
Max Superelevation See Section 2.04B See Section 2.04B See Section 2.04B See Section 2 04B
ttorlzontat Curvature See Table 2. 2 See Table 2. 2 Low Speed Curve Low Speed Curve (See
i (See Section 2.10) Section 2.10)
I Maximum Grade' 11% I 12% I 12% 12%
Minimum Stopping Sight See Table 2.2 ;:,ee Table 2.2 150 feet 150feet
Distance
Minimum Entering Sight See Table 2.2 . . .
Distance I
Typical Traveled Way 22 feel' 22 feet 22feel 22 feet
Typical Roadway Width I 32 fee1 7 28feel 24 feel 22 feet
Minimum Right,of-Way Width : i 56 feet 48 feel 40 feet' 40 feet'
, Minimum Half Street Width ! 20 feet 20 feet 20 teeJ 20 feet
Minimum One Way Paved 20 feet 20 teet 20 feet 20 feel
, Width
Minimum Sidewalk Width I See Section 3. 02 See Section 3.02 See Section 3.02 See Section 3.02
j Curb Type Verlical Vertical'/Rollad Verlical/Rolled Vertical/Rolled
1 See Section 2.20 for urban exceptions. Also. when Section 2.20 applies the curbing shall be vertical.
2 See Section 2.15 for one-way loops.
3 See Section 2.20 for res1denhal access connection requirements.
4 See Section 2.20 for urban exception criteria.
5 Designs-peed is a basis for determining geometric elements and does not imply posted or ,egally
pennissible speed.
6 Maximum grade may be exceeded for short distances. See Section 2.11.
7 Neighborh~d collt!ctor:, intersecting with arterials shall be 36 fee! wide for the first 150 foet. Sc::e
Section 4.05 for tapers.
'The right-of-way width may be reduced to minimum roadway width plus stnnn drainage, sidewalk,
and one-foot beyond road improvements including sidewalks, provided that the curbing is vertical, the
minimum clear znne requirements are met, and all poten!ial serving utilities are accommodated within
Page 12 Of27
CARE Response: Liberty Gardens LUAOB-093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
2.20 Exception for Maximum Dwelling Units on Urban Subcollectors
Proposed subcollectors serving new urban area developments with an average
density of seven to eight dwelling units per acre and that meet the access
requirements of Section 2.19 may serve up to 250 dwelling units, if approved by
the Development Engineer. ln this situation, the curbing shall be vertical. Prior
to approval, the applicant must submit a traffic circulation study demonstrating a
balanced traffic flow ofless than 1500 vehicles per day past any access point.
Street trees shall be mandatory along subcollectors serving higher densities of
seven to eight dwelling units per acre and shall be in conforrrnmce with Section
5.03.
Based on the known number of dwelling units for which 162'' Ave SE will serve as access, Urban Subcollector is not an
appropriate road classification for the extension.
Primary Access
Threadgill
Cavalla
Liberty Gardens
Liberty Lane
McKendry
Thatcher
Wilmot
15
34
37
12
1
1
1
101
So even at a bare minimum, the half-street and the proposed classification are both inappropriate. But even more traffic
must be expected.
Plus possible new connections to existing lots:
Lee 1
McNair 1
Mohr _1
3
Trips from Liberty Grove lots: 34
and lots north of 136": 18
52
Brendan -to develop: 35
Reasonable expectation: 191
An exception under section 2.20 is not available to this project because this area is zoned for 4 DUs per acre with a
maximum fully developed density of 6 DUs per acre (which would require TDRs) and with existing large lots can not be
expected to achieve the required 7 to 8 DUs per acre in the foreseeable future.
From the King County Roads Standards:
Page 13 Of27
CARE Response: Liberty Gardens LUA08-093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
2.07 Half Streets
A. A half street, figure 2-009, may be permitted as an interim facility when:
3. Traveled way shall be surfaced the same as the designated road type to a
widlh not less than 20 feet, sidewalk shall be constructed as required for
the desi =ated road tvne· and
6. The intersection of a half street shall be improved to full width standards,
Sidewalks are required on half streets.
Half street intersections must be built to full width standards. Yet, the Preliminary Road Improvements Plan still shows
only a half street intersection.
DocName Date Time Author Firm Page Para
Email: RE: Public . 02/25/08 09:18 Kristen Langley KC DOT 1 6
Disclosure Request: DOES :00
File Numbers L04P0034 AM
and L06P001
"So, we acknowledge that the criteria for half-street isn't appropriate, and have established (already , in the
case of the SEPA for Threadgill) that the cumulative impact of the pending applications require something
greater than half-street, but, the volumes don't rise to 'full-width' as an offsite (KCRS 1.03A)."
DocName Date
Email:RE: Public Disclosure 02/28/08
Request: ODES File
Numbers L04P0034 and
L06P001
"MINIMUM of 22-feet paving"
Time Author Firm Page Para
· Kristen Langley KC DOT 1 5
"Something greater than the minimum" is the the binding standard to be met. Provision of infrastructure to protect the
safety and welfare of the public is what is necessary.
DocName Date Time Author Firm Page Para
Email: RE: Public 02/25/08 09:18 Kristen Langley KC DOT 2 5
Disclosure Request: ODES :00
, File Numbers L04P0034 AM
and L06P001
[discussing possibility of increased parking and access to the High School ballfields and park via 164 Ave SEJ
" ... Even if they were successful, it would change the fundamental assumptions of the TIAs prepared to date -
and, they (the District) could reasonably be expected to be responsible (DOES, if still in the unincorporated
area) for some of these off-site improvements to 162"' Avenue SE, and. might have to construct widening
above and beyond the minimum 22-feet already contemplated."
KC staff agrees that if improvements are made for increased parking and access to the School ballfields and park via 164
Ave SE, the very impacts (inexperienced drivers and high volumes at night on a steep sloop with inadequate intersection
landing and inadequate intersection spacing) that we have argued all along will not only exist indeed. but that the TIA so
far submitted do not address these impacts. With the City of Renton's requirement of exactly these improvements to 164"
Ave SE, the inadequacy of the TIA has come to pass. An entirely new and complete TIA must be required.
Page 14 Of 27
CARE Response: Liberty Gardens LUAOB-093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
From the King County Roads Standards:
CHAPTER 3. DRIVEWAYS, SIDEWALKS, BIKEWAYS, TRAILS
3.02 Concrete Sidewalks
Sidewalks shall be required and construc:ted on urban category, curb and gutter
type streets, Figures 2-002 and 2-00:1, unless otherwise allowed by these
Standards or the County Road Engineer. 'They shall be located and constructed as
follows:
I. On all arterials, neighborhood collectors, subcollectors, suhaccess,
attached dwelling, business access streets, and industrial access streets,
both oid"S.
7. Sidewalks shall be a minimum width of 5 feet on residential access streets
and arterials. Minimum sidewalk width shall be six and one-half feet on
arterials if curb is next to traveled lane. Sidewalks shall be a minimum
width of eight feet on commcrc1al access streets.
Doc Name Date
Email:RE: Public Disclosure 02/28/08
Request: ODES File
Numbers L04P0034 and
L06P001
Time Author
Kristen Langley
Firm Page Para
KC DOT 1 4
·' ... the extension provides for an improved (curb/gutter/sidewalk) walkway route for school-aged pedestrians for
all the subdivisions: Liberty Gardens, Cavalla and Threadgill to the middle school in the area."
DocName Date Time Author Firm Page Para
Email: RE: Public 03/04/08 05:04 'Matthew Nolan KC DOT 1 From
Disclosure Request: DOES :00 Kristen
File Numbers L04P0034 AM Langley
and L06P001
" ... Threadgill, Cavall, LG --are required to install curb, gutter and sidewalk on the frontage, AND, as with
Threadgill, will be expected to provide curb, gutter and sidewalk on the common-off-site-to-all-three plats for the
portion of 162nd Ave SE that was required for Threadgill as (a1) a condition of SEPA (a2) a condition needed to
provide adequate school walkways to Maywood Middle School (b) will be required for Cavalla and LG as (b1)
potential SEPA conditions (b2) in lieu of an, in our opinion, an unapprovable Varinace to a long dead-end
roadway, and (b3) a condition of approval needed to provide adequate school walkways to Maywood Middle
School. .. "
DocName Date
04/15/08
Time Author Firm
Notes: Cavalla Re-
screening
"New road standards/need sidewalk on both sides.
Show sidewalk on full frontage"'
Bruce Whittaker KC ODES
Page Para
1
Despite the obvious need and the documented impact of all three proposed plats. the proposed walkway improvements
for the extended 162'' Ave SE are still discontinuous, inconsistent and wholly inadequate to serve the real needs for this
location. Please see the CARE Annotated Assessor's Map for details of the proposed walkway improvements (and gaps).
Further troubling, there are no walkway improvements whatsoever proposed for the children walking along SE 144" ST to
Page J50f27
CARE Response: Liberty Gardens LUAOB-093 for SEPAAppeal and Preliminary Plat Hearing 3/17(08
Maywood Middle School.
DocName
Report: Traffic Impact
Analysys for
Threadgill/Cavalla/Liberty
Gardens
Date
10/31/2006
Planned and Programmed Improvements
DocName Date
Time Author
Gary A. Norris,
PE PTOE
Time Author
Firm Page Para
DN Traffic Consultants 11
Page Para
' KC Transportation Needs
. Report 2008
Firm
KCDOT SPP-4
,018
'and
SPP-4
019
SPP-4018 SE 144~ St and 168th Ave SE Pedestrian Improvement: Install Crosswalk overhead light
SPP-4019 SE 144th St from 168'" Ave SE to 177'" Ave SE Pedestrian Improvement: Construct walkway
The TIA fails to mention existing locations of known projects on the adopted King County Transportation Needs Report for
pedestrian improvements for the school children walking to Maywood Middle School which will be adversely impacted by
traffic from the proposed project. This is a major omission.
Furthermore, the TIA fails to inspect, document or predict the impacts to any intersection on SE 144'" -neither the
proposed new intersection of 162"' Ave SE nor the increased traffic that will result with improved access to the
unimproved parkland and the Liberty High School ball fields that will result from the required improvements to 164'" Ave
SE or the impacts along the school walkway of SE 144th St from the project to Maywood Middle School. Because the TIA
presents no intersection analysis for any intersection on SE 144th ST, it must be considered incomplete and a new TIA
must be required.
From the King County Roads Standards:
2. Subcollectors
Subcollector streets are the second highest in the local roadway
classification hierarchy. Subcollectors provide circulation within
neighborhoods and typically connect to neighborhood collectors.
Although they typically allow direct driveway access there are some
project related exceptions.
Page 16 Of 27
CARE Response: Liberty Gardens LUA08-093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
Table 2.2
Urban Residential Access Streets Design Values
Design Speed (mph) 25 30 35
Horizontal Curvature, for 6% 135 215 320
Superelevation, Radius (Ft.)
Horizontal Curvature, for 4% 145 230 345 I
i
. Superelevation, Radius (Ft)
Horizontal Curvature, for 2% 155 250 375
Superelevation, Radius (Ft.)
Horizontal Curvature, Normal Crown 180 300 460
Section, Radius (Fl.)
Stopping Sight Distance (FL) 155 200 250
Entering Sight Distance (Ft.) 280 335 390 '
Page 17 Of:27
CARE Response: Liberty Gardens LUA08-093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
2.10 Intersections and Low-Speed Cuives
A. Intersections
I. Angle of intersection (measured at IO feet
beyond road classification right-of-way)
2. Minimum c<-'!1lerline radius (2-lane) (radii are
for minor or subaccess streets)
3. Minimum curb radius
a. Arterials and roads classified
neighborhood collector or higher:
b. Residential access street intersections
where the highest classification involved is
subcollector:
4. Minimum right-of-way line radius:
Minimum 85 degrees
Maximum 95 degrees
55 feet
35 feet
25 feet
25 feet
B. Spacing between adjacent intersecting streets, whether crossing or T-connecting, shall be
as follows:
When highest classification involved is:
Principal arterial
Minor arterial
Collector arterial
Neighborhood collector
Any lesser street cla~sification
Minimum centerline offset shall
he:
1,000 feet
500 feet
300 feet
150 feet
100 feet
SE 144" St is an Arterial Collector according to the 2006 Arterial Classification Map. The proposed intersection of 162"'
Ave SE with SE 144" St requires that there to be a minimum of 300 feet spacing to the next intersection. Centerline of
162" Ave SE ROW to centerline of 161" Se on the north side of Se 144• St is 177.42 feet. Centerline of 162" Ave SE
ROW to centerline of 161" Se on the south side of Se 144" St is approximately 135 feet.
SE 162" Ave SE extension to and intersection with SE 144'h St as proposed violates the basic King County road
standards specifications and must be denied.
If SE 162°' Ave SE extension to and intersection with SE 144" St is to be required, per KCC 14.42.060.C it was the
responsibility of the applicant to have applied for a variance before this application came to hearing. No variance was
sought.
From the King County Roads Standards:
Pagel80f27
CARE Response: Liberty Gardens LUA08~093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
2.11 Maximum Grade and Grade Transitions
A. Maximum roadway grade as shown in Sections 2.02 and 2.03 may be
exceeded for short distances of 300 feet or less, upon showing that no
practical alternative exists. Grades greater than 15 percent that exceed the
300-foot distance must be approved by the County Road Engineer through the
road variance process. Additionally, the maximum grade shall not exceed I 5
percent unless verification is ohtained from the Fire Marshal that additional
fire protect10n requirements will he met and the applicant's engineer must
demonstrate what method will be used to ensure drainage will he controlled.
Grades exceeding 12 percent shall he paved with hot mix asphalt (HMA) or
portland cement concrete (PCC).
B. Grade transitions shall be constructed as smooth vertical curves, without angle
points, except in intersections where the difference in h'fade is one percent or
less and upon approval of the County Road Engineer or Development
Engineer.
2.12 Stopping Sight Distance
t\.. Stopping Sight Distance (SSD) is the sum of two distances: the distance
traveled during perception and reaction time and the distance required to stop
the vehicle. The perception and reaction time used in design is 2.5 seconds.
1 On residential access street intersections where the 11.lghest classification involved is a subcollector, the
minimum curb radius is 25 feel
The stopping sight distance is calculated using a constant deceleration rate of
11.2 feet/second2
• SSD, see Tables 2.1 and 2.2, applies to street
classifications as shown in Sections 2.02 and 2.03.
B. Available stopping sight distance is calculated for a passenger car using an
eye height of3.50 feet and an object height of0.50 foot. Although AASHTO
allows a 2-foot object height, a 0.50-foot object height is used because ohjects
with a height between 0.5-foot and 2 feet may be perceived as hazards that
would likely result in an erratic maneuver.
C. When calculating stopping sight distance, use h 1=3.50 feet and h2=0.50 foot.
D. The grade of the roadway has an effect on the vehicle's stopping sight
distance. The stopping distance is increased on downgrades and decreased on
upgrades. When evaluating sight distance with a changing h'fade, use the
grade for which the longest sight distance is needed. Road grades other than
those shown in cxhihit 2-l must be interpolated.
Page 19 Of'27
CARE Response: Liberty Gardens LUA08-093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
Exhibit 2-1. Stopping Sight Distance on Grades
DOWNGRADE
DESIGN SPEED (MPH) 3 Percent 6 Percent 9 Percent
F.
60 598 638 686
55 520 553 594
50 446 474 507
45 378 401 428
40 315 333 354
35 258 271 288
30 205 215 227
25 158 165 173
20 116 120 126
Intersecting Stopping Sight Distance.
I. Stopping sight distances for the design speeds of proposed commercial
access streets, neighborhood collector streets and arterials must be met
when intersecting arterials.
2. The minimum stopping sight distance on proposed intersc1ction approaches
for all other access to intersecting roadways shall be 125 feet.
In light of the stopp·,ng distances listed in the King County Roads Standards, we also have considerable concern that the
reverse slope (roughly 2%) between the bottom of the 12 % grade and the proposed intersection of SE 144" is only about
150 feet as proposed. In the chart above, the minimum stopping distance for a 9% grade at 30 miles an hour is 227 feet.
This circumstance begs the conclusion that the proposed intersection of 162" Ave SE and SE 144" St must be
considered a particularly dangerous proposal.
Additionally, we find no consideration of the traffic flow patterns from the retail enterprise of Alpine Nursery, located at the
corner of 144th and 161 ", whose customers often arrive in very large vehicles or with trailers. Since the submitted TIA
failed to analyze any intersection on SE 144" St, there is no indication of what kind of turn lane, turn pocket, signage or
other safety mitigations should be required for the safe and smooth function of SE 144th St after extension of 162" Ave
SE.
No guard rail or wall or any other facility improvements have been proposed to be installed on the south side of SE 144th
ST to prevent a car which fails to stop at the end of the to-be-constructed 162nd Ave SE from landing in the current
residents' back yard. The substantially increased risk to life and property that will be borne by the owners and residents of
the property directly south of this proposed intersection is disproportionate to all the surrounding community and all due
care must be extended to prevent harm to them.
No secondary access is proposed with the current plat proposals. Because secondary access is readily available via the
Renton required improvements to 164" Ave SE, the extension of 162'' Ave SE is not necessary, and thus all impacts to
the streams and wetlands in the 162'' Ave SE ROW are 100% avoidable.
This wetland mitigation proposal is utterly obsolete. A new and complete analysis is necessary and must be required.
Page 20 Of '27
CARE Response: Liberty Gardens LUA08~093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
Conclusion
King County staff has a dismal record in their mitigation decisions in our community. Their previous review and guidance
of this application is again proven inadequate. They have consistently failed to adequately investigate, analyze and and
require mitigation to offset the real world impacts of subdivision applications that our community must suffer King County
Code specifies the KCRDCS as the legally binding standard to which new roads will be constructed in order establish
consistent rules that will protect the lives and interests of the citizens of King County. In the event that it may be possible
to grant exceptions to the King County Road Standards, the King County Code has established a formal, consistent
standard process by which an applicant may submit a proposal demonstrating that such exception shall provide for
mobility, safety and all other material requirements specified under the code -application for a road variance. Additionally,
King County has adopted rules that make variance applications, when need is known -and CARE has provided
numerous notification of need, should be sought before an application goes to public hearing.
Consistent review process and mitigation standards are critical to the fair application of the law to all citizens. Reviewing
staff must apply the same rules and the same processes to each application. They are accountable directly to the citizens
in this duty. When a King County agency fails to follow the process set in the adopted development regulations, it violates
the requirement of the authorizing state law, fails to act properly as an agent of the state and prevents the public oversight
and input that is guaranteed by law.
Compliance with the adopted standards is so rmportant that the punitive consequences are quite harshly defined in the
King County Code. The Hearing Examiner is authorized by the code to deny approval of this plat application tor failure to
comply. We believe the danger to the community posed by the proposed extension of 162" Ave Se to intersect with SE
144'" St to be so grave and so avoidable, that we request this entire application be denied entirely.
Document RCW 36.75.020
Quotation County roads -County legislative authority as agent of state -Standards.
All of the county roads in each of the several counties shall be established, laid out, constructed,
, altered, repaired, improved, and maintained by the legislative authority of the respective counties
as agents of the state, or by private individuals or corporations who are allowed to perform such
work under an agreement with the county legislative authority. Such work shall be done in
accordance with adopted county standards under the supervision and direction of the
county engineer.
Discussion King County acts as agent of the state in the regulation of the county roads. The state requires
that road construction be done in accordance with the adopted county standards.
Document RCW 36.708.030(5)
Quotation Nothing in this section limits the authority of a permitting agency to approve, condition, or
deny a project as provided in its development regulations adopted under chapter 36.70A
RCW and in its policies adopted under RCW 43.21 C.060. Project review shall be used to
identify specific project design and conditions relating to the character of development, such as
the details of site plans, curb cuts, drainage swales, transportation demand management, the
payment of impact fees, or other measures to mitigate a proposal's probable adverse
environmental impacts, if applicable.
Discussion State law allows King County to adopt those rules it deems necessary and sufficient to mitigate a
proposal's probable adverse environmental impacts.
Document KCC 14.42.005
Quotation Purpose • intent.
A. Chapter 36.75 RCW authorizes the county to perform all acts necessary and proper for
the administration of the county roads. County roads shall be established, laid out,
constructed, altered, repaired, improved and maintained by the legislative authority of the county
or by private individuals or corporations who are allowed to perform such work under an
agreement with the county legislative authorrty. The work and improvements shall be done in
accordance with adopted county standards under the supervision and direction of the county
road engineer
Page2J Of:27
CARE Response: Liberty Gardens LUAOS-093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
B. The purpose of the King County Road Design and Construction Standards ("the
standards") is to set forth specific, consistent and acceptable road design and
construction elements for developers and other private parties constructing or modifying road or
right-of-way facilities that require county licenses or permits and to establish uniform criteria to
guide the county's own design and construction of new county roads or reconstruction of existing
roads. The standards support the county's goals for achieving affordable housing, providing
adequate facilities for development in an efficient manner, complying with storm water
management and environmental and cultural resource policies. and balance these goals with
the general safety and mobility needs of the traveling public.
C. The county requires standardization of road design elements when necessary for
consistency and to ensure, so far as practicable, that motoring, bicycling, transit,
, equestrian and pedestrian public safety needs are met. Considerations include safety.
, convenience, pleasant appearance, proper drainage, economical maintenance and cultural and
environmental resource protection. The standards also provide requirements for the location and
installation of utilities within the right-of-way.
, Discussion The King County Council, directly citing the authorizing state law. adopted the KCRDCS as the
development standards for all county roads, Specifically, the county code specifies that all road
, work must be done in accordance with the KCRDCS. Further, the council codified that the road
design elements are necessary to ensure consistency and that public safety needs are met.
Document , KCC 14.42.010
'Quotation Adoption.
A "King County Road Standards," 2007, incorporated herein as Attachment A* to Ordinance
15753, are hereby approved and adopted as the King County standards for road design and
construction.
Discussion As required by state law, the county council formally adopted the KCRDCS by ordinance.
, Document RCW 36.708.040
Quotation : Determination of consistency.
I (1) A proposed project's consistency with a local government's development regulations
, adopted under chapter 36. 70A RCW, or, in the absence of applicable development regulations,
the appropriate elements of the comprehensive plan adopted under chapter 36.70A RCW shall
be decided by the local government during project review by consideration of:
(a) The type of land use:
(b) The level of development, such as units per acre or other measures of density:
(c) Infrastructure, including public facilities and services needed to serve the
development; and
(d) The characteristics of the development, such as development standards.
Notes: Intent -Findings -1995 c 347 §§ 404 and 405: "In enacting RCW 36.70B.030 and
36.70B.040, the legislature intends to establish a mechanism for implementing the
provisions of chapter 36.70A RCW regarding compliance, conformity, and consistency of
proposed projects with adopted comprehensive plans and development regulations. In
order to achieve this purpose the legislature finds that:
(1) Given the extensive investment that public agencies and a broad spectrum of the public are
, making and will continue to make in comprehensive plans and development regulations for their
communities, it is essential that project review start from the fundamental land use planning
choices made in these plans and regulations. If the applicable regulations or plans identify the
type of land use. specify residential density in urban growth areas, and identify and provide for
funding of public facilities needed to serve the proposed development and site, these decisions at
a minimum provide the foundation for further project review unless there is a question of code
interpretation. The project review process, including the environmental review process under
chapter 43.21 C RCW and the consideration of consistency, should start from this point and should
not reanalyze these land use planning decisions in making a permit decision.
Page 22 Of 27
CARE Response: Liberty Gardens LUA08~093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
(2) Comprehensive plans and development regulations adopted by local governments under
chapter 36. 70A RCW and environmental laws and rules adopted by the state and federal
government have addressed a wide range of environmental subjects and impacts. These
provisions typically require environmental studies and contain specific standards to address
various impacts associated with a proposed development, such as building size and
location, drainage, transportation requirements, and protection of critical areas. When a
permitting agency applies these existing requirements to a proposed project, some or all
of a project's potential environmental impacts will be avoided or otherwise mitigated.
Through the integrated project review process described in subsection (1) of this section. the
local government will determine whether existing requirements, including the applicable
regulations or plans, adequately analyze and address a project's environmental impacts. RCW
43.21C.240 provides that project review should not require additional studies or mitigation
under chapter 43.21C RCW where existing regulations have adequately addressed a
proposed project's probable specific adverse environmental impacts.
(3) Given the hundreds of jurisdictions and agencies in the state and the numerous communities
and applicants affected by development regulations and comprehensive plans adopted under
chapter 36.?0A RCW, it is essential to establish a unifonm framework for considering the
consistency of a proposed project with the applicable regulations or plan. Consistency should
be determined in the project review process by considering four factors found in applicable
regulations or plans: The type of land use allowed; the level of development allowed, such as
units per acre or other measures of density; infrastructure, such as the adequacy of public
facilities and services to serve the proposed project: and the character of the proposed
development, such as compliance with specific development standards. This uniform
approach corresponds to existing project review practices and will not place a burden on
. applicants or local government. The legislature intends that this approach should be largely a
matter of checking compliance with existing requirements for most projects, which are simple
or routine. while more complex projects may require more analysis. RCW 43.21 C.240 and
36. 70B.030 establish this uniform framework and also direct state agencies to consult with local
government and the public to develop a better format than the current environmental checklist to
meet this objective.
(4) When an applicant applies for a project permit, consistency between the proposed
project and applicable regulations or plan should be determined through a project review
process that integrates land use and environmental impact analysis, so that governmental
and public review of the proposed project as required by this chapter, by development
regulations under chapter 36.70A RCW, and by the environmental process under chapter
43.21C RCW run concurrently and not separately.
Discussion For a reviewing agencies recommended mitigations to be valid, they must be consistent with the
whole of the adopted regulations of the jurisdiction. The implementing agencies are not authorized
to second-guess the reasoning behind an adopted ordinance or regulation, nor are they allowed
to pick and choose the portions of the law that they think should apply to a given situation. The
intent of the state legislature is recorded here to apply the adopted law as a whole. Consistency
is determined in the project review process by considering such issues as the adequacy of public
facilities and compliance with specific development standards. The legislature specifically records
their intent that this approach should be largely a matter of checking compliance with existing
requirements. Consistency is a huge factor in the intent behind this legislation -especially the
need for all the government and public review processes to run concurrently and not separately.
Document KCC 14.42.060
Quotation Variances.
A. A road variance is required for any design or construction deviation from these
standards. Detailed procedures for applicants requesting variances and appealing variance
decisions are contained within a public rule that is available from the county road engineer or the
reviewing agency.
B. Any variances from these standards may be granted by the county road engineer upon
evidence that the variance is in the public interest and that requirements for safety,
function, fire protection, transit needs, appearance and maintainability are fully met, based
upon sound engineering and technical judgment.
C. Variance requests for subdivisions should be proposed at the preliminary plat stage and
Page 23 Of 27
CARE Response: Uberty Gardens LUAOB-093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
prior to any public hearing. All known variances must be approved prior to approval of the
engineering plans for construction. It is the responsibility of the county road engineer to interpret
the standards. Any anticipated variances from these standards that do not meet K.C.C. Title 17
shall also require concurrence by the fire marshal. (Ord. 15753 § 7, 2007: Ord. 8041 § 7, 1987).
Discussion The recommended mitigation has been documented by King County staff to potentially fail to
meet the standards for the required modifications to the intersection and approaches at SE 128"
ST and 160" AVE SE. The SEPA and Plat Hearings are the only mechanism by which the public
has access to the review process for this project to perform the oversight that is their right and
duty. Under the state laws defining the requirement for consistent application of design standards
in the review process. accountability to the public to stated repeated by the legislature as a driving
issue in the intent of the law. The adopted development regulations of King County in regard to
road standards and the appropriate process by which exceptions to those standards can be
granted sets the required process steps. It is obvious that in some circumstances, and
unanticipated situation may become known only after a public hearing has been conducted. Thus.
if during the engineering phase of a project the need for a variance is first determined, the law
does not require an applicant to start over, but instead may seek a variance for the newly
discovered situation. But when the likely need for a variance is known. and indeed documented
by reviewing staff prior to the public hearing, the public has every right under the law to expect the
variance to have been sought, considered and decided based on sound technical and legal
analysis. Otherwise, the public has no mechanism by which to make its interest known. nor for
individually affect citizens to act to protect their interests.
Page 24 Of 27
CARE Response: Liberty Gardens LUAOB-093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
Document KCC 14.42.070
Quotation Penalties. Failure to comply with these standards may be cause for denial of plan or
development permit approval, revocation of prior approvals, withholding and reductions of
financial guarantees, withholding of final inspection approval, withholding of occupancy
certificates, either temporary or permanent, legal action for forfeiture of financial guarantee. code
enforcement, and/or other penalties as provided by law.
Discussion Compliance with the adopted standards is so important that the punitive consequences are quite
harshly defined in the King County Code. The King County Hearing Examiner is authorized by the
code to deny approval of this plat application for failure to comply.
Document KCC 14.42.060
Quotation Variances.
B. Any variances from these standards may be granted by the county road engineer upon
evidence that the variance is in the public interest and that requirements for safety,
function, fire protection, transit needs, appearance and maintainability are fully met, based
upon sound engineering and technical judgment.
C. Variance requests for subdivisions should be proposed at the preliminary plat stage and
prior to any public hearing. All known variances must be approved prior to approval of the
engineering plans for construction. It is the responsibility of the county road engineer to interpret
the standards. Any anticipated variances from these standards that do not meet K.C.C. Title 17
shall also require concurrence by the fire marshal.
Discussion King County Code specifies the KCRDCS as the legally binding standard to which new roads will
be constructed in order establish consistent rules that will protect the lives and interests of the
citizens of King County. In the event that it may be possible to grant exceptions to the King County.
Road Standards, the King County Code has established a formal. consistent standard process by
which an applicant may submit a proposal demonstrating that such exception shall provide for
mobility, safety and all other material requirements specified under the code -application for a
road variance. An application for variance is required in order for any proposed exceptions of the
King County Road Standards may be granted. It is the responsibility of the applicant to have
applied for a variance before this application comes to hearing. Such application should have
been submitted and approved before this application is presented in Public Hearing before the
King County Hearing Examiner.
Further complicating the matter is the fact that no Inter-Local Agreement was executed between
King County and the City of Renton for the Liberty Annexation, so there is no 'jurisdiction haring'
agreement that provides any mechanism by which the King County Road Engineer (the variance
authority) to be engaged to consider any variance.
Page 25 Of 27
CARE Response: Liberty Gardens LUA08M093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
Document · RCW 43.21 C.240
Quotation Project review under the growth management act.
(2) A county, city, or town shall make the detemnination provided for in subsection (1) of this
section if:
· (b) The local government bases or conditions its approval on compliance with these
requirements or mitigation measures.
, Findings --Intent -1995 c 347 § 202: "(1) The legislature finds in adopting RCW 43.21 C.240 that:
(a) Comprehensive plans and development regulations adopted by counties, cities, and towns
under chapter 36.70A RCW and environmental laws and rules adopted by the state and federal
, government have addressed a wide range of environmental subjects and impacts. These plans,
regulations, rules, and laws often provide environmental analysis and mitigation measures for
project actions without the need for an environmental impact statement or further project
, mitigation.
(b) Existing plans, regulations, rules, or laws provide environmental analysis and measures that
avoid or otherwise mitigate the probable specific adverse environmental impacts of proposed
, projects should be integrated with, and should not be duplicated by. environmental review under
• chapter 43.21 C RCW.
(c) Proposed projects should continue to receive environmental review, which should be
conducted in a manner that is integrated with and does not duplicate other requirements. Project-
level environmental review should be used to: (i) Review and document consistency with
comprehensive plans and development regulations; (ii) provide prompt and coordinated
review by government agencies and the public on compliance with applicable environmental laws
and plans, including mitigation for specific project impacts that have not been considered and
addressed at the plan or development regulation level; and (iii) ensure accountability by local
government to applicants and the public for requiring and implementing mitigation
measures.
(d) When a project permit application is filed, an agency should analyze the proposal's
environmental impacts, as required by applicable regulations and the environmental review
'process required by this chapter, in one project review process. The project review process
should include land use, environmental, public, and governmental review, as provided by
the applicable regulations and the rules adopted under this chapter, so that documents
, prepared under different requirements can be reviewed together by the public and other
, agencies. This project review will provide an agency with the information necessary to make a
decision on the proposed project.
Discussion Consistent review process and mitigation standards are critical to the fair application of the law to
all citizens. Reviewing staff must apply the same rules and the same processes to each
application. They are accountable directly to the citizens in this duty. When a King County agency
fails to follow the process set in the adopted development regulations, it violates the requirement
of the authorizing state Jaw and fails to act properly as an agent of the state and prevents the
public oversight and input that is guaranteed by law
Document WAC 197-11-158
Quotation GMA project review -Reliance on existing plans, laws, and regulations.
(1) In reviewing the environmental impacts of a project and making a threshold determination, a
GMA county/city may, at its option, determine that the requirements for environmental analysis,
protection, and mitigation measures in the GMA county/city's development regulations and
comprehensive plan adopted under chapter 36.70A RCW. and in other applicable local. state, or
: federal laws or rules, provide adequate analysis of and mitigation for some or all of the specific
adverse environmental impacts of the project.
(2) In making the determination under subsection (1) of this section, the GMA county/city
shall:
Page 26 Of 27
CARE Response: Liberty Gardens LUA08-093 for SEPAAppeal and Preliminary Plat Hearing 3/17/08
(c) Base or condition approval of the project on compliance with the requirements or
mitigation measures in the comprehensive plan, subarea plan, applicable development
regulations, or other local, state, or federal rules or laws ...
Discussion A reviewing agency must base the recommended mitigation on the adopted development
regulations.
Document KCC 14.42.030
Quotation Applicability.
A. The standards apply prospectively to all newly constructed or modified road and right-
of-way facilities, both public and private, within King County. The standards apply to
modifications of roadway features or existing facilities that are within the scope of reconstructions,
required off-site road improvements for land developments or capital improvement projects when
so required by King County or to the extent they are expressly referred to in project plans and
specifications. These standards are not intended to apply to resurfacing, restoration, and
rehabilitation projects as those terms are defined in the Washington state Department of
Transportation Local Agency Guidelines Manual, as amended.
C. Construction shall be performed in accordance with the standards and with due regard
to public safety.
Discussion The recommended mitigation include modifications to the roadway and/or right-of-way at the
intersection and approaches to SE 128" ST and 160" AVE SE due to the finding of adverse
impacts resulting from the proposed project. The code again emphasizes the necessity of
construction to be performed according to the adopted standards and with due regard to public
safety. Particularly because this mitigation is based on the existence of a known and exceptional
public safety hazard, and in light of the fact that staff has documented the public concern for
safety at this intersection, failure to fully comply with the process specified in the adopted
regulations is a grave error.
This application comes to the public hearing stage with numerous and critical issues unresolved. There is still no
agreement between staff and applicant of whether access to the plat will be via 162'' Ave SE, 164" Ave SE or both. So
dire is the incompleteness of this proposal that the applicant themselves request yet another postponement and declared
that, "The Applicant has several outstanding issues that need to be resolved prior to the plat hearing for it to be
productive."
We agree.
We believe that the Hearing Examiner must reject this application outright as authorized by King County Code, and that is
the preferred remedy we request.
The Hearing Examiner is authorized to grant the relief we seek, as well as the responsibility to ensure that this proposed
proJect meets all the requirements of State and Local laws. regulations and policies. We have demonstrated the
deficiencies of this application in light of these laws. regulations and policies.
Should the Hearing Examiner chose instead to approve the proposed plat subject to conditions, we request clear findings
of fact in regard to the road standards violations we have identified and the precise method by which the anticipated
safety deficiencies will be addressed.
This Hearing is the last opportunity to ensure that adequate administratively and legally enforceable mitigations are
required of and implemented with this project.
We are the Public. Our interest is in protecting our homes. preserving our neighborhoods, promoting fair and reasonable
use of property to all land owners and preventing harm to our community.
Re}f'fctfully s,ubmitted,
7(----.1w 2 ~·vC•-/f --/.. 1c,, -1..,we'hdolyn H,g/'I"--.JJ ,
Page '27 Of 27
'
ED McCARTHY, P.E., PS
Hydrology• Hydraulics • Engineering
March 3, 2008
Mr. Bruce Whittaker
King County DDES
900 Oakesdale Avenue SW
Renton, WA 98055
Re: Liberty Gardens, Cavalla Development, and Threadgill Plat
Recommended Stormwater Mitigations
Dear Mr. Whittaker;
9957 171 Avenue SE
Renton, WA 98059
(425) 271-5734
FAX (425) 271-3432
As you are aware, the proposed developments of Liberty Gardens, Cavalla, and a portion of the
Threadgill Plat all drain to the conveyance system along SE 1441h Street (Figure!). The results
of the hydraulic assessment I prepared for the downstream conveyance system (June 15, 2007)
predicted flooding along the north side of SE 1441h Street and at the intersection of 1601h Avenue
SE. There has also been residential flooding at SE 142°d Place, which is adjacent and tributary to
the downstream system of the proposed developments. After consideration of the basin and
downstream conditions, I offer the stormwater mitigations described below for the proposed
plats to address existing flooding problems along SE 144th Street and at the end of SE 142°d
Place.
Onsite Stormwater Mitigation
Conservation flow control standards are required for the proposed Liberty Gardens, Cavalla, and
Threadgill developments (King County Department of Natural Resources, January 2005). The
hydraulic analysis I prepared (June 15, 2007) indicates that the 18-inch diameter pipe along the
south side of SE 144•h Street has a capacity of 4 to 6 cubic feet per second. Flows with return
periods of 2 to 5 years likely surcharge the 18-inch diameter pipe system. The roadway and ditch
system along the north side of SE 144th Street convey the major portion of higher flows. A HEC-
RAS analysis of the roadway conveyance system (Ed McCarthy, PE, PS, June 2007) for the I 00-
year peak rate indicates that the ditch system between 162"a Avenue SE and 160th Avenue SE
has adequate capacity to convey the 100-year peak rate. However, driveway culverts along this
reach as well as the culverts at the intersections of 1601h Ave SE and 161 '' Ave SE would be
overtopped.
The driveways along the north side of SE 144"' Street generally rise above the street as they
approach the residence they access. Representative driveways along the north side of SE 144th
Street that would be flooded with higher flows are illustrated in Photos I and 2 of Attachment A.
As the photographs suggest, the driveway would easily be discemable under a situation where
flood flows inundate the northerly ditch and driveway culverts. The presence of flooding
driveway culverts would not create unreasonable difficulties for emergency access to the
residences.
K.C. D.D.E.S.
•
Mr. Bruce Whittaker
Page 2
March 3, 2008
Based on the HEC-RAS hydraulic model used to assess the conveyance system along SE 144th
Street, increasing the flow rate by 0.5 cubic foot per second, or more, would increase the flood
stage above one or more of the downstream driveway culverts by more than V. inch (Attachment
B). An increase of more than 0.5 cubic foot per second would occur for the 100-year peak flow
rate if Flow Conservation Standards were adopted for the proposed projects. As such, this would
constitute aggravating an existing severe flooding problem (King County Surface Water Design
Manual, p. 1-25).
On the other hand, adopting Level 3 flow control would mitigate the impacts of the projects on
this downstream flooding area. The predicted 100-year stage in the downstream flood flow path
would not be increased. In light of the downstream conditions, providing Level 3 detention
standards is an appropriate stormwater mitigation for each of the proposed developments. For the
Threadgill Plat, this recommended higher level of flow control would apply only towards the
western portion of the site draining to SE 144th Street. This mitigation would satisfy Core
Requirement #3 of the Surface Water Design Manual (Table 1.2.3.A on page 1-29).
I conducted KCRTS simulations for the Cavalla and Liberty Gardens plats to estimate the
stormwater detention volumes that would be required to meet Level 3 flow control standards
(Attachment C). For Cavalla, I estimated a required storage volume of 132,300 cubic feet. For
Liberty Gardens, I estimated a required storage volume of 114,600 cubic feet. These estimated
volumes do not include a factor of safety which would increase the required volumes, nor do
they account for the effects ofrequired flow control BMPs, which would reduce the required
storage volume (King County Department of Natural Resources, January 2005).
Extension of 162nd Avenue SE
As part of the proposed plats, 162nd Avenue SE will be extended from SE 144th Street to SE
1361h Street. Like the proposed plats, the proposed roadway will provided stormwater flow
control and water quality treatment. Using the same rational as for the proposed plats, Level 3
flow control and basic water quality treatment would be an appropriate mitigation in managing
stormwater from the proposed roadway.
The proposed extension of 162nd A venue SE offers an opportunity to improve drainage
conditions for residents at SE 142nd Place. I understand that an open channel along the west side
of the 162nd Avenue SE right-of-way (Figure 2) will be tightlined under proposed developed
conditions. The design of the tightline should be extended far enough upstream such that it
effectively collects drainage that flows along the east boundary of the Gragg property located at
16046 SE 142nd Place. Both the proposed tightline and stormwater control system for 162nd
Avenue SE should have an overflow outlet that maintains the flow route along the north side of
SE 144th Street that is predicted to occur with higher flows.
Proposed Solutions to Drainage Problems at SE 142nd Place
In previous corre';rondence to you, I was supportive of the idea of extending the stormwater pipe
system along 160 Avenue SE in effort to direct flows from the drainage course directly north of
SE 142nd Place to the existing 12-inch diameter culvert system along 160th Avenue SE and
subsequently to the storm conveyance pipe along SE 1441h Street. This modification to the storm
'
/
Mr. Bruce Whittaker
Page3
March 3, 2008
system would be intended to relieve some of the flows from the flooding problem at residences
along SE 142°d Place. After assessing this proposal in additional detail, I am no longer
supportive of it. I believe that adding flows to the pipe system along the lower segment of 1601
h
Avenue SE could create a flooding problem for the residence at the bottom of the hill. With
higher flow rates, a backwater would develop in the flat reach of pipe at the bottom of 160th
Avenue SE and surcharge an inlet pipe adjacent to the residence, increasing the risk of flooding
of the adjacent residential property and structure.
I believe that the most effective way to relieve the drainage problem that now occurs at
properties at the end of SE 142°d Place would be to tightline the channel that now traverses the
east property boundaries oflots located at the end of SE 142°d Place (Figure 2). This
modification to the drainage system could be included in the plans for the proposed extension of
162nd Avenue SE. Managing runoff in this manner will resolve a drainage problem that has been
bothersome for several years for at least three residents at SE 142nd Place.
Gragg Property
The Gragg property, located at 16046 SE 142nd Place, has an additional concern that could be
resolved with the proposed extension and improvements along 162°d A venue SE. The onsite
sewage disposal system on the Gragg property has been adversely affected by groundwater
seepage from the channel along the north property boundary. As development in the upstream
basin has increased runoff volumes to the channel, the onsite sewage system has at times failed.
The design of the sanitary sewer along 162nd Avenue SE should include a stub out connection for
the Gragg parcels to correct this ongoing problem.
Please note that the applicants for the proposed plats willingly offer the mitigations that would
benefit the property owners along SE 142nd Place provided that the mitigations can be designed
and implemented without incurring unreasonable delays that may be confronted in acquiring
construction easements, permits, or other construction-related authorizations.
SE 144TH STREET
LEVEL 3 DOWNSTREAM DRAINAGE
ANALYSIS
Prepared for:
Mr. Dave Petrie
811 So. 273rc1 Ct
Des Moines. WA 98J 98
KBS Development
12320 NE 8th Street Suite 100
Bellevue WA 98005
Eagle Creek Land & Development, LLC
13701 SE 253rd St
Kent. WA 98042
RECEIVED
JUL 1 I 2007
KING COUNTY
LAND USE SERVICES
Prepared bv:
Ed McCarthy. P.E., P.S.
9957 171°' Avenue SE
Rcr,tun. WA 98059
Tel. 14251 271-5734
Fax i425i 2713432
Table 2. Peak Flow Rates at Key Locations
Location Return Period (Years)
2-Yr /CFS) 10-Yr (CFS) 25-Yr /CFS) 100-Yr /CFS)
CB-ISA 9.86 15.70 19.08 24.66
160'" Ave SE 11.23 17.65 21.31 27.42
CB-5 11.72 18.37 22.23 28.52
CB-4C 4.25 6.86 8.36 10.86
CB-4 16.09 25.43 30.85 39.72
The hydraulic model HEC-RAS was used to model the roadway surface and ditch conveyance
under flood conditions for the 100-year peak flow rate. The I 00-year peak rate assumes that 5
cubic feet per second is conveyed in the 18-inch diameter storm pipe along the south side of the
road. The remainder of the flow is assumed to be conveyed in the roadway and roadside ditch.
The roadway conveyance capacity was evaluated from CB-1 lA (HEC-RAS Sta 0+00) to the
intersection of 162"d Avenue SE (HEC-RAS Sta 10+10). HEC-RAS analysis of the roadway
conveyance system for the 100-year peak rate indicates that the ditch system between l 62"d
Avenue SE and I 60'h Avenue SE bas adequate capacity to convey the I 00-year peak rate.
However, driveway culverts along this reach would be overtopped. In addition, the HEC-RAS
model predicted that flow depths would be up to 0.7-foot deep over driveways. HEC-RAS
results are presented in Appendix D.
Roadway flooding along SE 144th Street would be considered as "severe roadway flooding
problem" according to King County standards (King County Department of Natural Resources,
January 2005) due to the following conditions:
• Between the intersection of l 62"d Avenue SE and 160th Avenue SE driveway culverts
along the ditch on the north side of SE 144th Street'would become overtopped, posing
a threat of unsafe access due to indiscernible driveway edges.
• Floodwater over the driveways on the north side of SE i 44'h Street between 160th
Avenue SE and CB-1 IA would be deeper than 0.5 foot, posing a severe impediment
to emergency vehicle access.
2.4 Flooding Locations and Flood Flow Paths
Flows with return periods of 2 to 5 years likely surcharge the 18-inch diameter pipe system.
Flows were predicted to leave the pipe and ditch drainage system at a number oflocations
including CB-4C, CB-JOA, CBI4A, CB-ISA, CB-15A-l, and CB-18A. Between the intersection
of 162°d A venue SE and 160th A venue SE, overflow from the catch basins is conveyed to the
west in the roadside ditch on the north side of the road. From the intersection at 160th Avenue
SE, overflow from the catch basins is conveyed to the west mainly along the north side of the
road. Flooding covers the north half of the north travel lane at locations near CB-I IA. From CB-
I IA, floodwater is conveyed further west in the north travel lane until it reaches a low lying area
located north of CB-9A. Depending upon the magnitude of flows, the floodwater either
2-8
SE J 4¢1' Street-June 2007
Page I of2
•
Whittaker, Bruce
To: Dave Petrie; Ed McCarthy; Dan Balmelli
Cc: Wayne Potter; Foley, Steve; Sleight, Brian; Tibbits, Chad
Subject: RE: Level 3 Offsite Analysis Addendum Oct 12, 2007
Ed/Dave/Dan/Wayne,
I received and reviewed the Level 3 Addendum prepared by Ed McCarthy on the 160th/162nd drainage systems.
We need to have the original Level 3 Downstream model updated to show the changes to the downstram
predictions, if a portion of the flow is to be directed south in the 160th corridor. I appreciate Mr McCarthy's
narrative in the above letter; but we need to see the model re-run to see the results. The analysis should also
show where pipes or conveyance need to be constructed to accomplish the routing of flows to the south.
Please also note that a drainage adjustment is required to route a portion of the flow to the south on 160th
corridor.
If you have any questions, please call me at 206-296-7211
Thanks!
Bruce Whittaker
From: Dave Petrie [mailto:DavePetrie@comcast.net]
Sent: Thursday, September 27, 2007 10: 18 AM
To: Ed McCarthy; Dan Balmelli
Cc: Wayne Potter
Subject: Re: Bypass Letter, Sept 24, Ed to Dave
I don't think anyone has ever considered the idea of activating the currently inert 12" culvert system on 160th Ave as a
11 diversion".
Instead, it is a sort of Safety/Overflow Valve to mitigate the peak flows that have for -30 years damaged the properties of
Gragg, Chin and Gammell. As I understand it, this is the only way that KC can avoid a lawsuit from these Complainants*.
In my view, it is up to KC Roads Maintenance to design this overtl ow bypass to perform in this way so as it will NOT be
considered a diversion. My pix (with text, attached) shows this precisely by the location of the 12" culvert branching directly
south of the 24" SE crossover just upstream of Nabors residence. (Note: I expected Ed to cover to this in his Report, and
recommend that he do that in his final version of the Addendum).
Of course I will pay the remaining balance due, once the terms (Task 3) of the Contract are fulfilled. Again, Bruce wants this
option submitted as an Addendum (not a letter** from Ed to Dave).
• Following tlus e-mail, I will PDF comments from the Level I Downstream Analysis by DMP Inc, dated Nov I 2, 2003. In particular, note the Complaint Evaluation
Memo by Alan Meyers,
dated 3-19-97
** I gather that the letter format W-ds Ed's way of checking out that we are On the Same Page; planned all along to submit the option as an Addendum.
----Original Message -----
From: Dan Balmelli
To: Ed McCarthy ; 'Dave Petrie'
10/18/2007
Cc: Wayn~ePQtt<er
Sent: Wednesday, September 26, 2007 10:21 PM
Subject: RE Bypass Letter, Sept 24, Ed to Dave
Page 2 of2 •
Dave, I have reviewed Eds letter and your comments. I reccomend that Ed modify the letter to delete the
reference to the wetland and then issue it with your agreement to pay him his remaining balance. We can then
submit a final proposal to Bruce to keep moving the project to public hearing. Bruce sent an email to me and
confirmed that the county would not consider this option as a diversion since it was the original direction of flow.
Please confirm this is acceptable so we can move on. Dan
From: Ed McCarthy [mailto:edwardjmccarthy@comcast.net]
Sent: Monday, September 24, 2007 5:37 PM
To: 'Dave Petrie'
Cc: Wayne Potter; Dan Balmelli
Subject: RE: Bypass Letter, Sept 24, Ed to Dave
Dave,
I appreciate your concerns for your neighbors, but I still believe that my letter is objective, which I intended it to
be. It is actually in your best interest to know what the issues may be with the proposed diversion. I could delete
the reference to the wetland, since I don't think it will likely be an issue as it has on other past similar issues I've
worked on. The remainder of the letter will stay the same. In my opinion, the County will likely approve of the
proposal.
Do you agree to pay me the balance you owe me if I provide you with a revised letter with the edit I mentioned
above? If not I will refrain from further work on this project and seek other means for obtaining reimbursement
per our contractual agreement.
Ed
10/18/2007
, Page 1 of 1
Whittaker, Bruce
From: Cassidy, Jon
Sent: Monday, March 05, 2007 10:14 AM
To: Dave Petrie; Lazaro, Desi
Cc: Steve Vottheim; Whittaker, Bruce; Wayne Potter; Chad Armour; Gillen, Nick; Sleight, Brian;
Schwartz, Rick; Finlinson, Jason
Subject: RE: Culvert Work-West-side 160th Ave SE
Dave, Thanks for your e-mails. I have contacted Brian Sleight to try and find out the status of the project you have proposed
but have not been able to talk with him yet The Engineer previously in charge of the investigation has been promoted to a
new Department and I do not know who took his place or the status of the work, The work Rjck's crews were doing was
related to repair of the historic drainage panern which crosses over 160th at 14115 and drains to the swale that ultimately
Bows down 162 SE in the unopened right of way, This system has never flowed over the rise and down 160th to SE 144th as
you have suggested in your sketches. As you know there is a DNRP regional pond on 162nd SE at SE 144th and they will
need to approve any changes to the proposed drainage system. I will continue to work with Brian to see if a solution can be
found but you should continue to work with your contact at ODES to ensure compliance with your pennits. I left you a
voice mail as well and will get back to you with any new information that I receive.
Jon A Cassidy
Managing Engineer
King County DOT
Roads Maintenance Section
From: Dave Petrie [mailto:DavePetrie@comcast.net]
Sent: Saturday, March 03, 2007 10:26 AM
To: Lazaro, Desi
Cc: Cassidy, Jon; Steve Vottheim; Whittaker, Bruce; Wayne Potter; Chad Armour; Gillen, Nick
Subject: Culvert Work-West-side 160th Ave SE
The work Schwartz was doing the week of Feb 12 is meaningless: The flow southward is totally
BLOCKED , as shown in these pix. Schwartz claims he is working under design plans made by your
group. I want to see those plans.
I want the elbow that diverts drainage southeasterly into the 24" culvert CROSSING 160th Ave opened
to permit flow down the west side of 160th Avenue!
This will mitigate the horrendous flow that now sluices down the west side of the proposed extension of
162nd Ave SE from the SW comer ofmy Liberty Gardens plat to 144th Street SE.
This stormwater is NOT a SA Stream.
Dave Petrie
253-946-6619
03/05/2007
Page 1 of 1
Whittaker, Bruce
From: Cassidy, Jon
Sent: Monday, March 05, 2007 10:14 AM
To: Dave Petrie; Lazaro, Desi
Cc: Steve Vottheim; Whittaker, Bruce; Wayne Potter; Chad Armour; Gillen, Nick; Sleight, Brian;
Schwartz, Rick; Finlinson, Jason
Subject: RE: Culvert Work-West-side 160th Ave SE
Dave, Thanks for your e-mails. l have contacted Brian Sleight to try and find out the status of the project you have proposed
but have not been able to talk with him yet. The Engineer previously in charge of the investigation has been promoted to a
new Department and 1 do not know who took his place or the status of the work. The work Rick's crews were doing was
related lo repair of the historic drainage pattern which crosses over 160th at 14115 and drains lo the swa!e that ultimately
flows down 162 SE in the unopened right of way. This system has never flowed over the rise and down 160th to SE 144th as
you have suggested in your sketches. As you know there is a DNRP regional pond on 162nd SE at SE 144th and they will
need to approve any changes to the proposed drainage system. 1 will continue to work with Brian to see if a solution can be
found but you should continue to work with your contact at DDES to ensure compliance with your pem1its. l left you a
voice mail as well and will get back to you with any nev.' information that I receive.
Jon A. Cassidy
Managing Engineer
King County DOT
Roads Maintenance Section
From: Dave Petrie [mailto:DavePetrie@comcast.net]
Sent: Saturday, March 03, 2007 10:26 AM
To: Lazaro, Desi
Cc: Cassidy, Jon; Steve Vottheim; Whittaker, Bruce; Wayne Potter; Chad Armour; Gillen, Nick
Subject: Culvert Work-West-side 160th Ave SE
The work Schwartz was doing the week of Feb 12 is meaningless: The flow southward is totally
BLOCKED, as shown in these pix. Schwartz claims he is working under design plans made by your
group. l want to see those plans.
I want the elbow that diverts drainage southeasterly into the 24" culvert CROSSING 160th Ave opened
to permit flow down the west side of 160th Avenue!
This will mitigate the horrendous flow that now sluices down the west side of the proposed extension of
162nd A vc SE from the SW corner of my Liberty Gardens plat to 144th Street SE.
This stormwater is NOT a SA Stream.
Dave Petrie
253-946-6619
01/31/2008
Page I of I
Whittaker, Bruce
From: Cassidy, Jon
Sent: Monday, March 05, 2007 10:14 AM
To: Dave Petrie; Lazaro, Desi
Cc: Steve Vottheim; Whittaker, Bruce; Wayne Potter; Chad Armour; Gillen, Nick; Sleight, Brian·,
Schwartz, Rick; Finlinson, Jason
Subject: RE: Culvert Work-West-side 160th Ave SE
Dave, Thanks for your e-mails. I have contacted Brian Sleight to try and find out the status of the project you have proposed
but have not been able to talk with him yet. The Engineer previously in charge of the investigation has been promoted to a
new Department and l do not know who took his place or the status of the work. The work Rick's crews were doing was
related to repair of the historic drainage pattern which crosses over 160th at I 4 l 15 and drains to the swale that ultimately
flows down 162 SE in the unopened right of way. This system has never flowed over the rise and down 160th to SE 144th as
you have suggested in your sketches. As you know there is a DNRP regional pond on 162nd SE at SE 144th and they will
need to approve any changes to the proposed drainage system. I \,:ill continue to work with Brian to see if a solution can be
found but you should continue to work with your contact at DDES to ensure compliance with your pem1its. I left you a
voice mail as wel! and will get back to you with any new information that I receive.
Jon A. Cassidy
Managing Engineer
King County DOT
Roads Maintenance Section
From: Dave Petrie [mailto:DavePetrie@comcast.net]
Sent: Saturday, March 03, 2007 10:26 AM
To: Lazaro, Desi
Cc: Cassidy, Jon; Steve Vottheim; Whittaker, Bruce; Wayne Potter; Chad Armour; Gillen, Nick
Subject: Culvert Work-West-side 160th Ave SE
The work Schwartz was doing the week of Feb 12 is meaningless: The flow southward is totally
BLOCKED , as shown in these pix. Schwartz claims he is working under design plans made by your
group. I want to see those plans.
I want the elbow that diverts drainage southeasterly into the 24" culvert CROSSING 160th Ave opened
to permit flow down the west side of 160th Avenue!
This will mitigate the horrendous flow that now sluices down the west side of the proposed extension of
162nd Ave SE from the SW corner of my Liberty Gardens plat to 144th Street SE.
This stormwater is NOT a SA Stream.
Dave Petrie
253-946-6619
03/05/2007
ragt; 1 u1 .J
Whittaker, Bruce
From: Cassidy, Jon
Sent: Thursday, April 17, 2008 7:31 AM
To: Dave Petrie; Gregg Zimmerman; Whittaker, Bruce
Cc: Adriana Gragg; Wayne Potter; Ty Pendergraft; Kolin Taylor; Daniel Balmelli; Curtis Schuster;
Dougherty, Linda; Arima, Debbie; Weder, Andrea; lwatani, Elvira; Lazaro, Desi
Subject: RE: Inactive Culvert System-160th Ave SE
Dave,
I do not believe there are any standard flow splitters available due to the variability in flow patterns and
conditions. If you would like a reference manual for the design of a flow splitter, the King County Surface Water
Design Manual is a good source of information . It will also provide you with the requirements that need to be met
in order to divert fiows for one system into another. The King County Code requires this type of modification to a
drainage system to be designed by a Professional Engineer with storm drainage design experience. I believe the
City also allows the use of the County manual for drainage design, but am not certain if a Professional Engineer is
required. If you intend to permit these proposed changes in the City after annexation, I would recommend that
you talk with their Building Department staff for the City requirements.
I have been unable to locate any requests from "Chinn" in our Citizen Action Request data base regarding
flooding in this vicinity so I am unable to respond to concerns in this regard. The pipe system installed on the hill
climb area of 160 Ave SE between SE 144 St and SE 142 PL was installed to provide a safer pathway for
pedestrians and school children. The County Road Standards do not allow for the use of pipe smaller than 12-
inches in diameter due to difficulties with cleaning and regular routine maintenance. There may be excess
capacity in this system as you suggest, but downstream conditions must be investigated to ensure no one
downstream is adversely affected. The County Surface water Design Manual provides details on how to
accomplish this analysis. For your convenience, the following is a link to the manual:
http://q_n r.metro kc. gov /wlr/dss/man ua I. htm
Please let me know if you need additional information.
Sincerely,
Jon A. Cassidy
From: Dave Petrie [mailto:DavePetrie@comcast.net]
Sent: Friday, April 04, 2008 3:12 PM
To: cassidy, Jon; Gregg Zimmerman; Whittaker, Bruce
Cc: Adriana Gragg; Wayne Potter; Ty Pendergraft; Kolin Taylor; Daniel Balmelli; Curtis Schuster; Dougherty,
Linda; Arima, Debbie; Weder, Andrea
Subject: Re: Inactive Culvert System-160th Ave SE
Let's try it this way.
There is a flooding problem and there is an easy way to fix it:
Unused culvert capacity to reduce the flooding to a manageable state already exists, although it needs to be
completed in the section soon under the purview of Renton. Does it make sense to install a dual 12" culvert
system down 160th Avenue with no (apparent) intent to ever utilize it?
Everyone should be able to agree that the solution to Chin n's, et al pleading (at the January 28 Renton Council
Meeting) to "Stop the flooding of the Smith property" can be easily mitigated* by putting the aforementioned inert
culvert system into play. Mo_st of the culvert work (at trivial cost) is in the northern section (with new sewer
06/18/2008
Page 2 of3
line) soon to be re-asphalted by Renton funds.
I think the three Complainants' are already looking to Renton as their savior, so why worry about?
"' Our hydraulic survey indicates that the current 13 cfs coursing around the NE corner of the Rich Lea Plat can be reduced to a manageable nine cfs,
the remaining four cfs being bypassed in an overflow sense down the existing culvert system along the southerly portion of 160th Ave
** Chinn, Gragg, Gammell
----Original Message ----
From: Cassidy, Jon
To: Dave Petrie ; Gcegg Zimmerman ; Whittaker Bruce
Cc: Adriana Gragg ; Wayne Potter; Ty Pendergraft ; Koljn TeiY1Dl; l)_si_tJiel_El_aJrn..filli ; Curtis S<::lwster ;
Dough.E,l:!y Linda ; Arima Debbie ; V'Jec:Jer, Andrea
Sent: Friday, April 04, 2008 1 :44 PM
Subject: RE: Inactive Culvert System-160th Ave SE
Good afternoon Mr. Petrie;
Thank you for your email of March 17, 2008 expressing your concerns that an illegal diversion of a drainage
system on 160th Avenue SE is flooding properties in the area.
Field staff from the King County Road Services Division (RSD) visited the site and inspected the drainage
system on 160th Avenue SE from SE 144th Street north to approximately 13800 block. Based on RSD staff
investigations, the following have been determined.
It is unlikely that the cross culvert on 160th Street is an "illegal diversion." Based on the contours in this area, it
indicates that water flowing south along 160th Avenue SE would naturally flow into the depression on the Smith
property, and not continue south along 160th Avenue SE. In fact, there still exists the original pipe that
conveyed the water from the west side of 160th Avenue SE at 14415 to the east side, and into the depression
on the Smith property. There is no evidence that storm water ever flowed south to SE 144th Street along 160th
Avenue SE (see the attached pdffile).
In 1977, the developer of Rich Lea Crest channelized the flow as it entered the plat from the north (Smith
property) along the northerly line and thence south along the easterly line of Rich Lea Crest in the unopened
162nd Avenue SE right-of-way. Additional flow from developments to the north of SE 144th Street may cause
flooding issues along SE 144th Street due to the low gradient 12" perforated pipe system in place there now.
Problems created or exacerbated by the development of an area is the responsibility of the developer. All
development work needs to be coordinated through your contact with the King County Department of
Development and Environmental Services (DOES).
Thank you again for bringing your concerns to our attention. If I can be of further assistance, please contact me
at 206-296-8148.
From: Dave Petrie [mailto:DavePetrie@comcast.net]
Sent: Monday, March 17, 2008 2:50 PM
To: Cassidy, Jon; Gregg Zimmerman; Whittaker, Bruce
Cc: Adriana Gragg; Wayne Potter; Ty Pendergraft; Kolin Taylor; Daniel Balmelli; Curtis Schuster
Subject: Inactive Culvert System-160th Ave SE
In the wake of completion of the sewer extension from 144th Street SE to 140th Street, the
imminent re-asphalting (pix029) of this 1600' section presents a Golden Opportunity to
06/18/2008
Page 3 of3
lessen the flooding problem of Chinn/Gragg/Gammell et al extant for 33 years.
The flooding is caused by the (illegal) diversion in 1975 by Leroy Nabor (deceased): Nabor's
lawn was being flooded during heavy rains by overtopping of the culvert/ditch system on his
west side of 160th Avenue. Due to recent developments (Hamilton Place, Evendell, Nichols
Place, Liberty Grove), the flooding of properties at the east end of 142nd Place has reached
crisis stage.
The Complainants have been frustrated by inaction from KC on this matter, flooding reports
dating back to the 1994. KC cites the 5-year historic flow rule. But it is unlikely that general
rule could be sustained in a court proceeding, considering the unusual circumstances
involved.
Accordingly-and recognizing that Renton will soon annex the northerly 70% of the 160th
Avenue culvert system along the sewer line-Chinn and Gragg testified at the January 28
Renton Council Meeting. Chinn requested that Renton "stop the flooding of the Smith
property" adjacent north, as a means to correct the aforementioned diversion by Nabor.
The PDF attachment by hydrologist McCarthy discusses activating this now dry/inactive
culvert system; which should qualify as a partial response to the Chinn pleading. Also see
attachment Drainage160Avetxt.jpg.
If the top of the 12" inlet pipe (green circle, pix 010) flowing southerly on 160th Ave were
made level to the 24" diversion pipe across 160th Ave, the flow eastward across the north
property line of Chinn/Gragg would see -30% reduction during peak flows. This should be
enough to end the problem*.
The drawing on attachment 2008-03-15 also shows the ditch flooding westward that occurs
on the north side of 144th Street under peak flows. IMO, an 18" culvert should replace the
puny and often blocked 12" culvert now there. Currently, this section on 144th Street is under
the purview of KC, as is the aforementioned southerly 440' of 160th Ave.
Dave Petrie
253-946-6619
Liberty Gardens Developer
* An additional and related problem is LOS on 160th Ave-beginning at 142nd Pl-a design that would not Pass
Code today. Sometime in the future, Renton may wish to reduce its current 20% grade to -11 %, Old
Timers in the region remember when 160th Ave ended at the crest of this hill. And all the storm water from the
north passed down the 160th Ave ROW.
06/18/2008
Whittaker, Bruce
From:
Sent:
To:
Dave Petrie [DavePetrie@comcast.net]
Wednesday, September 26, 2007 9:02 AM
Whittaker. Bruce
Subject: Drainage Bypass Proposal
Page 1 of 1
Attachments: 2006-01-04 GraggTxt 054.jpg; 2006-02-26 Drainage24.jpg; 2007-03-18 Rosario 013txt.jpg;
CulvertFlow 031txt.jpg; CulvertFlowTxt 010.jpg; CulvertFlowTxt 009.jpg; 2006-02-23
Pond091.jpg; 2D06-03-07DrainageT2 004.jpg; 2006-03-23 003txt.jpg
From letter to Ed McCarthy:
Summary
Page one, listing advantages, is Right On. Page two, listing "--issues of concern" could be easily modified with an optimistic
f1avor without losing content.
Comments:
I.Road Flooding Problem-Allen Bowdle (15928 SE 144th Sttcet, NW comer of 144th Street and 160th Avenue intersection)
reports no flooding. Wonders why the 12" culvert system contains no flow, even during the worst rainstorms. The attached
pix shows Jeff Sappenfield (15846 SE 143rd Street, back yard fronting on 160th Ave) pointing to a CB on the west side of
160th Ave, says flow 11 never seen 11 in this culvert system.
This morning, I called Rick Schwartz (KC Roads Maintenance Crew Chief) about his patch work at the subject intersection.
He said the work done February 2006 was to replace a homemade screen over a culvert with a regulation CB.
Any "road flooding problem" (Item l) is overtopping of the inadequate ditch/culvert system flowing westward along the
north side of 144th Street: Most of this flow originating from the stormwater rushing down the west side of the 162nd Ave
ROW (and into Gragg's, Chin's and Gammell's property from the eastward leg of that stormwater before it reaches 162nd
Ave).
2. The "nuisance flooding problem" (Gragg, Chin, Gammel Complaint) gets to the heart of my primary concern about the
deficiency of the Report. I want to avoid turmoil at the Plat Hearing. Gragg says that their attorney advised them to Hold
Back until they see what unfolds at the LG Plat Hearing. Gragg is adamant that the presently inert culvert system must be
activated including a culvert section passing under 142nd Street SE to bypass a portion of the storm water illegally diverted
by Leroy Nabor (1975).
3. The idea of "--tight-lining the runoff down the proposed extension of 162nd Ave SE" is good. BTW, in the meeting with
Whittaker (August 12), he said that Kris Langley (DDES Transportation) seems to prefer this, worried about wayward cars
plunging into the 8' deep chasm conveying the stormwater.
4. IMO, the statement about "diverting drainage from this wetland system" is unnecessary and inflammatory (to some). Any
wetland on the Smith property is a product of the aforementioned illegal diversion by Nabor. I would like Item 4 deleted.
As a sidebar, in May 2000, Dave Casey (my engineer at that time) said that Whittaker wanted the 18" CMP, now crossing
144th street (at CB-I8A), enlarged to 24", so as to handle the flows inadequately handled by the ditch/culvert system along
the NORTH side of 144th street. This crossover CMP is not shown in your Figure 6. The reasoning then follows that if this
crossover is enlarged, the culvert system along the SOUTH side of 144th should also be enlarged to 24" for consistency.
I am also puzzled that your diagrams in the Report do not show this enormous runoff down the 162nd Avenue ROW. Related
to this, I wire-brushed Whittaker (August 12 meeting) a bit for "reigning you in" to emphasize 144th Street. I was also
surprised that Bruce seemed unaware of the Gragg et al flooding problem, or the incomplete culvert system along 160th Ave
that these Complainants demand be completed soon: Over the past three years, I have talked _:,8-times with Gragg about this,
and he knows the Right Thing to Do. And I am with him.
09/28/2007
I
B--12 Wetland Consulting, Inc.
1.0
LIBERTY GARDENS
CRITICAL AREAS ANALYSIS REPORT
and CONCEPTUAL MITIGATION PLAN
INTRODUCTION
This report describes jurisdictional wetlands and streams observed on the Liberty
Gardens (Petrie) property, a roughly square, 8.9-acre property located off J 64'h Avenue
SE in unincorporated King County, Washington.
The site is surrounded by a school to the east, residential and undeveloped forest to the
south. undeveloped forest to the west, and residential properties to the north.
The site contains a small Class 3 intermittent stream with associated Class 2 riparian
wetland surrounding the stream.
1..:
\ ,,,
2.0 METHODOLOGY
..,., .... 1 '
~,,;<" .'.?..-~,%
~' "''l
Ed Sewall of B-twelve harked the wetland edges and the centerline of the stream on the
,ite on September 12, 200L Darcey Miller verified the delineation on September 28,
004.
iii colors were identified using the 1990 Edited and Revised Edition of the Munsell Soil
·tor Charts (Kollmorgen Instruments Corp. 1990). The wetland on site was identified
'lg methodology described in the Washington State Wetlands Identification Manual
WOE, March 1997). This is the methodology currently recognized by King County
A Sewall Wetland Consultina. tn~ ~
•iiill.i· .. ·· .. -,--... --= ------------------------------------==--
5.1 Driveway Crossing
RE: Wetland Report/Conceptual Mitigation
Liberty Gardens/#A 1-186
B-12 Wetland Consulting, Inc.
November J 9, 2004
Page 6
We believe that the driveway crossing the wetland/stream meets the requirements of the
"Driveway Crossing Wetland" and "Stream Crossings" portions of the King County
Code (Sections 21A.24J30.N and 21A.24.370.G). The road crossing is necessary, as no
other alternative is practical, The impact will be minimized in that the bridge will avoid
direct wetland and stream impacts. In addition, the driveway at each end of the bridge
will be supported by retaining walls, so as to avoid fill slopes that would extend into the
wetland and buffers. The wetland hydrology and flood storage capacity are not expected
to change; the bridge will allow the hydrology to continue to flow through, and wetland
will not be filled.
The stream crossing will also comply with the King County Code, Section 21A.24.370.G
in that the design employs a bridge so as not to disturb the stream flow. The stream is not
considered a salmonid stream; therefore, the crossing will not affect ESA species. The
bridge footings will not be placed below the OHWMs of the stream. The crossing,
because it is a bridge, will not diminish the flood-carrying capacity of the stream. This
crossing will be the only crossing of the sensitive area.
5.1.J Impacts Analysis and Conceptual Mitigation Plan
The impacts to the sensitive areas associated with the crossing will be fairly minor. As
noted above, the proposed crossing is at the same location as an existing path and
footbridge. The driveway crossing will impact a small portion of the Class 2 wetland
(358 sf) only in that the bridge will be located over it (See Sheet W-1.) Approximately
20 linear feet of stream will be located under the proposed bridge. The driveway areas on
each end of the bridge will be a maximum of20' wide, and therefore will affect a total of
2,165 sf of buffer. This width will include both the driving surface and the retaining
walls. Additional construction details will be provided in future engineering plans.
The impacts associated with this construction activity include minimal loss of wildlife
habitat functions and an insignificant loss of water quality functions. Vegetation to be
affected in the sensitive areas is mainly scattered herbaceous and shrub plants, as well as
several evergreen and deciduous trees. However, all efforts will be made to avoid trees
during driveway construction. Stormwater storage capacity is not significantly impacted,
as the culvert will maintain the historic hydrologic flow.
The mitigation opportunities on the site are very limited, as the majority of the site is
densely forested. Mitigation for the impacts to the sensitive areas includes buffer
addition and the enhancement of buffer areas near the driveway. Areas that are currently
scrub-shrub or deciduous forest will be planted with scattered conifers. Buffer addition
for the buffer impacts will be provided at a I:! replacement ratio (mitigation: impact),
and will therefore be approximately 2,165 sf. Buffer addition for the wetland/stream
impacts will be provided at a 2: I replacement ration (mitigation: impact) and will
1
CIVIL ENGINEERH~G, LANO f-'LANNING. SURVEYING. ENVIRONMENTAL SERVICES
King County
Department of Development and
Environmental Services
Land Use Services Division
Attn: Ms. Trishah Bull, Planner II
Current Planning Section
900 Oakesdale Avenue S.W.
Renton, WA 98055-1219
N ovcmber 22, 2006
RE: Resubmittal of Additional Information and/or Studies
Preliminary Plat of Liberty Gardens
King County File No. L04P0034
Our Job No. 12424
Dear Ms. Bull:
RECEIVED
NOV 2 2 2006
KING COUNTY
LAND USE SERVICES
l8-E~)SION I
LO+POO!>i
I am enclosing the following documents for your use in reviewing the proposed plat of Libe1ty Gardens.
L Twenty-five copies of the revised plat map, road/drainage plan, and park plan prepared by
Barghausen Consulting Engineers, Inc.
2. Ten copies of the 162nd Avenue S.E. extension plan
3. Ten copies of a Level II Traffic Impact Analysis prepared by DN Traffic Consultants dated
October 31, 2006
4, Twenty-four copies of the revised SEPA Checklist dated November 19, 2006
For your use in reviewing the enclosed documents, the following is a brief summary to the Plat Screening
Transmittal letter dated May 24, 2005.
Recreation Space: Per KCC 2JA.]4,]80, the proposed plat is required to provide 390 square
feet of recreation space per lor. Provide a conceptual recreation plan indicating the type of
improvements (Le. sport court, play structure, benches, landscaping, etc.) proposed. For
developments of 26-50 dwelling units, at least two or more of the recreation facilities listed shall
be provided in addition to the tot lot or children's play area:
a. playground equipment;
b.
C.
sport court;
,port field;
d. tennis court; or
e. any other recreation facility proposed by the applicant and approved by the director.
Response: As required by KCC 21A.l4.l80, we have provided a preliminary park and landscape
plan that incorporates two play structures. Please note the project is proposing an underground
18215 72ND AVENUE SOUTH KENT, WA 98032 (425) 251-6222 /425} 251-8782 FAX
BRANCH OFFICES t OLYMPIA. WA + TACOMA. WA t SACRAMENTO. CA t TEMECULA. CA
www.barghausen.com
King County
Department of Development and
Environmental Services
Land Use Services Division
Attn: Ms. Trishah Bull. Planner II
Cun-ent Planning Section -4-November 22, 2006
King County. With this application we are submitting the prefen-ed option of extending
162nd Avenue S.E. to S.E. 144th Street. A plan and profile of this proposed extension has been
enclosed for review and approval.
Wetlands:
The wetland areas were flagged and surveyed however the flagging for Wetland C is no longer
there. Wetland C will need to be re-flagged and verified. Please contact Nick Gillen at
206-296-7141 after the re-flagging is completed.
Response: It is our understanding from the previous engineer (Daley-Mon-ow-Poblete, Inc.) that
this information was provided to King County and reviewed by Nick Gillen. As a result of the
revised plat layout, approximately 2,686 square feet of wetland and approximately
15,538 square feet of buffer will be disturbed as a result of the extension of 162nd Avenue S.E.
We have provided an increase in the on-site stream/wetland buffer of 16,868 square feet of buffer
makeup area. With respect to the lost wetland area, we are proposing to provide a wetland
mitigation payment. This option was discussed with Nick Gillen at the King County meeting
several months ago. A report on the impacts of Liberty Gardens frontage improvements is being
prepared by Chad Armour, LLC and will be submitted to King County under a separate cover
letter. Furthermore, as a result of the extension of 162nd Avenue S.E. for the plats of Liberty
Gardens, Cavalla, and Threadgill, a stream enhancement plan submitted under a separate cover
letter.
Please note that we have also enclosed 24 copies of the revised SEPA Environmental Checklist. As
discussed, the preliminary plat of Liberty Gardens has been revised based on comments received from
King County with regard to secondary access, frontage improvements, and the proposed street vacations.
We have revised the preliminary plat and associated documents accordingly.
GWP/tep/ath
l 2424c.005.doc
enc: As Noted
cc: Mr. David Petrie w/etJr;....
Respectfully,
G. Wayne Potter
Project Manager
Mr. Curtis Schuster, KBS Development Corporation
Mr. Daniel K. Balmelli, Barghausen Consulting Engineers, Inc.
Mr. Ali Sadr, Barghausen Consulting Engineers, Inc.
' •
CHAD ARMOUR, LLC 6500 1261
h Avenue S.E.
Bellevue, Washington 98006-3941
(425) 641-9743 (425) 643-3499 (fax)
May 16, 2007
Mr. Dave Petrie
811 South 273'd Court
De Moines, Washington 98198
Subject: Conceptual Wetland Mitigation Plan (revised)
Liberty Gardens Preliminary Plat (L04P0034)
King County, Washington
\{:i@9Ecbad\J \ Sl ON
Ii Ii.
' -I_, ___ •• ~-,_-
RECEIVED
JUL 11 2007
KING COUNTY
LAND USE SERVICES
Dear Mr. Petrie L.n4Poo~+
We revised our conceptual mitigation plan based on information provided to us by Mr.
Nick Gillen in the meeting we had on February 28, 2007 and the fee-in-lieu spreadsheet
on March 14, 2007. As you will recall, we chose the fee-in-lieu option to mitigate for
unavoidable impacts to wetlands because the area available on the site for mitigation is
the location of a mature forest. The following describes our approach in revising the
conceptual mitigation plan including the estimated cost to construct a wetland off of the
site.
PROPOSED DEVELOPMENT PLAN
Mr. Dave Petrie (Proponent) proposes to construct 37 single-family homes on the 8.95-
acre Liberty Garden site (see Preliminary Plat of Liberty Gardens). To do so, it will be
necessary to construct new roads and storm management facilities (see Preliminary
Grading and Storm Drainage Plan of Liberty Gardens). The road will impact a total of
2,387 square feet (sf) of Class 2 wetland and 14,840 sf of buffer (Table 1 and
Preliminary Plat of Liberty Gardens). It will also impact an intermittent stream that flows
through one of the wetlands and across the site. We understand that the planned
development is vested under the King County Sensitive Areas regulations.
CONCEPTUAL MITIGATION PLAN
The proposed mitigation plan is to:
• Protect a portion of the wetland associated with the intermittent stream;
• Protect the intermittent stream;
• Protect the associated buffer;
• Fill a portion of two wetlands and associated buffer;
• Increase the width of buffer adjacent to wetland adjacent to the stream to make
up for lost buffer;
• Enhance the buffer makeup areas; and
• Pay the County a fee to create a 7,161 sf wetland off of the site.
C:/Jobs/BCE/Petrie/Fee In-Lieu Letter(revised).doc 1
Chad Armour, LLC
Liberty Garden Revised Mitigation Plan Mr. Dave Petrie
King County, Washington
Table 1 -Wetland and buffer impact and makeu areas'
• based on Preliminary Grading Plan (revised) of Liberty Gardens
• 961sf + 1,426 sf
' to be made up according to KKC 21A.24.137 Resource Mitigation Reserve
' 8,379sf + 6,207sf+ 254sf
EXISTING CONDITIONS
According to B-12 Wetland Consulting (2004) and our observations over the last several
years, the upland forest is composed of an overstory of mature big-leaf maple (Acer
macrophyllum), red alder (A/nus rubra), western red cedar ( Thuja plicata). Douglas-fir
(Pseudotsuga menziesi1), and western hemlock (Tsuga heterophyl/a). The understory
supports salmonberry (Rubus spectabilis), Indian plum (Oem/eria cerasiformis), hazel
nut (Cory/us comuta), sword fern (Po/ystichum munitum), salal (Gau/theria shallon), and
bracken (Pteridium aquilinum).
Wetland AIB (Southern Wetland)
The southern wetland is a Class 2 wetland that consists of a narrow strip of forest
adjacent to a Class 3 intermittent stream (B-12 Wetland Consulting, 2004). The wetland
supports an overstory of red alder and black cottonwood (Populus balsamifera) trees.
The understory supports salmonberry, lady fern (Athyrium filix-femina), and tall
mannagrass ( Glyceria elata).
Wetland C (Northern Wetland)
The northern wetland is a Class 2 wetland dominated by immature red alder trees,
salmonberry shrubs, and lady fern (B-12 Wetland Consulting, 2004).
Mature Trees In the Reduction and Makeup Areas
As indicated on Table 2 and the Significant Tree Retention Plan of Liberty Gardens, 20
medium-to large-sized deciduous and conifer trees will be lost due to the proposed
development. To offset this loss, a total of 21 medium-to large-sized deciduous and
conifer trees will be protected in buffer makeup areas.
C:/Jobs/BCE/Petrie/Fee In-Lieu Letter(revised).doc 2
Chad Armour, LLC
05/16107
'
Liberty Garden Revised Mitigation Plan
King County, Washington
• see Significant Tree Retention Plan for details
CONSTRUCTION PLAN
Mr. Dave Petrie
We developed this plan to mitigate for lost wetland and buffer area and functions by
assuming that a 7,161 sf wetland will be created off of the site and 14,840 sf buffer will
be enhanced on the site. We used the general guidance for completing fee-in-lieu
worksheet for offsite mitigation construction costs (Attachment A) to determine the
materials and labor to construct a wetland (King County, Undated). Table 3 illustrates
the suggested plants and habitat amenities to be installed in the created wetland and
enhanced buffer.
Off-Site Wetland Creation
We assume that:
• It will be necessary to purchase urban land;
• A total of 92 trees and 205 shrubs will be installed in the created wetland at a
rate of 0.041 plants/sf (Table 3);
• A mixture of native herbaceous plant species will be broadcast seeded on the
wetland creation area;
• 9 snags and 6 logs will be installed in the wetland creation area; and
• It will take 4 hours to deconsolidate the soil, compost will be added around each
of the installed plants in a circle 3 feet (ft) in diameter and 3 inches (in) deep,
and the site will be irrigated by way of a permanent irrigation system
(Attachment A).
On-Site Buffer Enhancement
In the buffer enhancement areas, we assume that machine encroachment will be limited
to trackhoe excavators used to install snags and place logs. We assume that the
crushed shrubs and herbs will recover. We also assume that:
• A total of 38 western red cedar trees will be installed 20 ft on center to increase
the density of conifer trees in the buffer make up areas;
C:/Jobs/BCE/Petrie/Fee In-Lieu Letter(revised).doc 3
Chad Armour, LLC
05116/07
Liberty Garden Revised Mitigation Plan
King County, Washington
Table 3 -Plant and Habitat Amenit Installation Guide
western red
cedar Thu·a licata
western red
cedar Thu·a licata
Total Trees
black Lonicera
twinberrv involucrata
clustered Rosa
rose oisocama
Pacific Physocarpus
ninebark caoitatus
red-osier Camus
doowood stolonifera
western
crabapple Ma/us fusca
Total
Shrubs
Tellima
randiflora
Stachys
coole i
large-leaved Geum
avens macro h I/um
tall
manna GI ceria e/ata
tufted Deschampsia
ces itosa
Oenanthe
Sna s
Los
various 0.041 I/sf
various 20 ft oc
various 0.041 pl/sf
various 0.041 pl/sf
various 0.041 pl/sf
various 0.041 ol/sf
various 0.041 pl/sf
seed broadcast
seed broadcast
seed broadcast
seed broadcast
seed broadcast
16" to 24" dbh; 30'
Ion
16" to 24" dbh; 30'
Ion
Mr. Dave Petrie
Quantit ~~-~-=~---------11
Total Wetland Buffer
92 92 0
38 0 38
130 92 38
41 41 0
41 41 0
41 41 0
41 41 0
41 41 0
205 205 0
X X
X X
X X
X X
X X
28 9 19
21 6 15
' 7,161 sf; to be made up off site according to KKC 21A24.137 Resource Mitigation Reserve
b 15,004 sf; to be made up and enhanced on-site
C:/Jobs/BCE/Petrie/Fee In-Lieu Letter(revised).doc 4
Chad Armour, LLC
05116/07
,
Liberty Garden Revised Mitigation Plan
King County, Washington
Mr. Dave Petrie
• It will not be necessary to install shrubs and herbs because a dense layer of
shrubs and a robust assemblage of herbs are present in the buffer enhancement
areas;
• 19 snags and 15 logs will be installed;
• The snags and logs will come from trees harvested on the site;
• A signed split-rail fence will protect the Southern Wetland, the intermittent
stream, and associated buffers.
MONITORING
The Proponent will monitor the on-site mitigation areas for at least three years following
installation in the summer.
The Proponent has included costs in the Mitigation Reserves Program, Fee-In-Lieu
Worksheet to allow for monitoring the off-site wetland for at least three years following
installation. The "fee-in-lieu" revenue that the County will receive in conjunction with this
Proposal constitutes the full extent of the Proponent's responsibility for monitoring
associated with the proposed wetland fill and subsequent mitigation efforts.
MAINTENANCE
The Proponent will maintain on-site mitigation area as follows:
• Remove weeds for three years after installation. Weeds include non-native
vegetation, particularly Himalayan blackberry, reed canarygrass, and evergreen
blackberry; and
• Replace trees that die during the 3-year monitoring program to maintain the
minimum 80 percent survival rate.
The Proponent has included costs in the Mitigation Reserves Program, Fee-In-Lieu
Worksheet to allow for maintenance of the off-site wetland during the three year
monitoring program. The "fee-in-lieu" revenue that the County will receive in conjunction
with this Proposal constitutes the full extent of the Proponent's responsibility for
maintenance associated with the proposed wetland fill and subsequent mitigation efforts.
CONTINGENCY PLAN
If there is difficulty achieving the performance standards on the site, the Proponent
proposes to work with the County to develop a contingency plan. Contingency plans can
include, but are not limited to: additional plant installation and plant substitutions of type,
size, quantity, and location. Such a contingency plan shall be submitted to the County
by December 1 '' of any year when deficiencies are discovered.
The Proponent has included costs in the Mitigation Reserves Program "Fee-In-Lieu
Worksheet" to allow for a contingency plan should deficiencies in the off-site wetland be
discovered during the three year monitoring program. The "fee-in-lieu" revenue that the
County will receive in conjunction with this Proposal constitutes the full extent of the
Proponent's responsibility for contingency measures associated with the proposed
wetland fill and subsequent mitigation efforts.
C:/Jobs/BCE/Petrie/Fee In-Lieu Letter(revised).doc 5
Chad Armour, LLC
05/16/07
Liberty Garden Revised Mitigation Plan
King County, Washington
SCHEDULE
Mr. Dave Petrie
The Proponent anticipates executing this plan at the first available opportunity following
the receipt of the necessary approvals from the County. Assuming construction occurs
the summer of 2007, the first monitoring event will occur the following spring. The
Proponent will submit a monitoring report as indicated previously. Maintenance will
occur within four months following submission of the monitoring report. Subsequent
monitoring, reporting, and maintenance will follow the same schedule during the
subsequent years.
LIMITATIONS
Work for this project was performed, and this mitigation plan prepared, in accordance
with generally accepted professional practices for the nature and conditions of the work
completed in the same or similar localities, at the time the work was performed. It is
intended for the exclusive use of Mr. Dave Petrie and his assigns for specific application
to the referenced property. This report is not meant to represent a legal opinion. No
other warranty, express or implied, is made.
It should be noted that wetland mitigation planning is an inexact science. Biological
professionals may disagree on the nature and extent of mitigation plans. Final
acceptance of this wetland mitigation plan is the responsibility of the penmitting authority.
Accordingly, the wetland mitigation plan developed for this plat should be reviewed by
the appropriate permitting authority prior to committing to detailed planning and design
activities.
REFERENCES
8-12 Wetland Consulting, Inc. 2004. Liberty Gardens Critical Areas Analysis Area
Report & Conceptual Mitigation Plan, King County WA. Prepared for Mr. Dave
Petrie, 811 S. 273'd Ct., Des Moines, WA 98198.
King County. Undated. Mitigation Reserves Program, Fee-In-Lieu Worksheet.
C:/Jobs/BCE/Petrie/Fee In-Lieu Letter(revised).doc 6
Chad Armour, LLC
05116107
'
,,
Liberty Garden Revised Mitigation Plan
King County, Washington
Mr. Dave Petrie
Any questions regarding our work and this plan, the presentation of the information, and
the interpretation of the data are welcome and should be referred to the undersigned.
Sincerely,
Chad Armour, LLC
C44~
Chad Armour
Principal
Attachments:
Figure 1 -Vicinity Map
Figure -Preliminary Plat Map of Liberty Gardens
Figure -Preliminary Grading and Storm Drainage Plan of Liberty Gardens
Figure -Significant Tree Retention Plan of Liberty Gardens
Attachment A -Mitigation Reserves Program. Fee-In-Lieu Worksheet
cc: Wayne Potter, Barghausen Consulting Engineers
Nick Gillen, King County DOES
CJJobs/BCE/Petrie/Fee In-Lieu Letter(revised).doc 7
Chad Armour, LLC
05/16/07
CHAD ARMOUR, LLC
May 16, 2007
Mr. Curtis Schuster
KBS Development Corporation
12320 NE B'h Street, Suite 100
Bellevue, Washington 98005
Subject: Conceptual Wetland Mitigation Plan
162nd Avenue SE -Proposed Extension
King County, Washington
Dear Mr. Schuster:
6500 1261h Avenue S.E.
Bellevue, Washington 98006-3941
(425) 641-9743 (425) 643-3499 (fax)
chad@chadarmour.com
RECEIVED
JUL 1 1 2007
KING COUNTY
LAND USE SERVICES
The following plan presents our approach to mitigating for unavoidable impacts to the
buffer of Type 3 streams. We first looked for the opportunity to make up lost area on the
site. Then, assuming that off-site mitigation is necessary and possible, we estimated the
cost to rehabilitate an off-site degraded buffer.
PROPOSED DEVELOPMENT PLAN
Three different plats, Cavalla, Liberty Gardens, & Threadgill, are soon to be the location
of single-family homes (Figure 1 ). Access to these plats is primitive or non-existent and
will need to be constructed and upgraded. The preferred alternative to access these
three sites is to construct a half a road (162nd Avenue SE) extending north from SE 1441h
Street. This road will be about 625 feet (ft) long and connect with the soon to be
constructed 162nd Avenue SE along the western boundary of the Liberty Gardens
Preliminary Plat (Figure 2). The road extension project for the three development
proposals is being managed by KBS Development Corporation (Proponent).
We understand that the streams associated with the 162nd Avenue SE extension is
subject to the sensitive areas ordinance. We also understand that because there is not
enough area available on site to make up for unavoidable impacts, additional mitigation
will use the Mitigation Reserves Program MAIN FILE Copy
EXISTING CONDITIONS
A Type 3 stream flows down the 162nd Avenue SE Right of Way (Figure 2 -Primary
Type 3 Stream). The drainage originates north and west of the Right of Way (ROW). It
is alternately located in a roadside ditch and buried culvert adjacent to 1581h Avenue SE,
SE 1361h Street, and 1601h Avenue SE before it is discharged to the Smith property
(Parcel No. 145750-0110). After flowing across the Smith property initially as sheet flow
and then in a culvert/ditch system, it is discharged to an "engineered" ravine adjacent to
Rich Lea Crest. Here the walls of the stream are short and steep and lined with quarry
spalls. The stream turns south when it meets the 162nd Avenue SE ROW and flows
through a deep narrow ravine. The stream discharges to an engineered (ie.,
constructed) stormwater detention pond that is connected to an underground stormwater
conveyance system that presumably discharges to the Cedar River.
C:/Jobs/BCE/Cavalla/Fee In-Lieu Letter.doc
Chad Armour, LLC
(
05/1~
~,0
162"d Avenue SE Extension Mitigation Plan
King County, Washington
KBS Development
Another Type 3 stream (Secondary Type 3 Stream) flows into the northern or upper end
of the storm water retention pond. This stream crosses Liberty Gardens and a cleared
area to the south before joining the Primary Type 3 stream.
Stream Buffer
The plant communities in the 162nd Avenue SE ROW adjacent to the stream include
immature forest, a thick tangle of blackberry shrubs, and mowed grass. The buffer
adjacent to the stormwater pond along the lower -250 ft of the ROW generally supports
grass and a few Douglas-fir (Pseudotsuga menziesil) trees. From the pond's eastern
slopes and a point about -100 ft to the east the plant community includes a few
deciduous trees growing through dense Himalayan blackberry (Rubus discolor) shrubs.
The upper or northern -300 ft of the ROW is the location of an immature forest
composed of big-leaf maple (Acer macrophyllum), Douglas-fir, black cottonwood
(Popu/us balsamifera), and red alder (A/nus rubra) trees growing among a thick tangle of
shrubs, including blackberries. In one location the back of a home and associated out
building in Rich Lea Crest are located within a few feet of the west bank of the Primary
Type 3 Stream.
CONCEPTUAL MITIGATION PLAN
The plan is to:
• Straighten the Primary Type 3 Stream;
• Route the Secondary Type 3 Stream through a culvert;
• Enhance the remaining available buffer following road construction; and
• Pay the County a fee to enhance buffer off of the site.
CONSTRUCTION PLAN
The site is too small to accommodate mitigation entirely on the site. As such, the plan is
to enhance as much of the degraded on-site buffer as possible (-15,000 square feet [sf])
and pay the County the equivalent fee to mitigate for buffer impacts that cannot be
achieved on the ROW by enhancing 14,500 sf of degraded off-site buffer (Table 1).
On-Site Buffer Enhancement
We assume that machine encroachment will be limited to trackhoe excavators used to
install snags and place logs. We also assume that most if not all of the crushed shrubs
and herbs will naturally recover. We further assume that:
• The blackberry shrubs will be removed to expose bare mineral soil and prepare
the area for planting;
• A total of 71 conifer and 54 deciduous trees will be installed individually 11 ft on
center (OC) to increase tree density (Table 2);
• A total of 490 shrubs will be installed in clumps 5 ft OC to promote a robust
native shrub layer;
• The ground will be covered (2:80%) with at least three different native herbaceous
plant species; and
• . A total of 2 snags and 2 logs will be installed.
C:/Jobs/BCE/Cavalla/Fee In-Lieu Letter.doc 2 05/16/07
Chad Armour, LLC
162"d Avenue SE Extension Mitigation Plan
King County, Washington
KBS Development
areasa
Fee In-lieu Off-site buffer make up
• based on Preliminary Road Improvement Plan and Profile of 162nd Avenue SE
Extension
b stream channel occupies -2,500 sf
Off-Site Buffer Enhancement
We assume that:
• It will be necessary to purchase urban land;
• A total of 120 trees and 475 shrubs will be installed in a degraded buffer at a
rate of 0.041 plants/sf (Table 2);
• A mixture of native herbaceous plant species will be broadcast seeded on the
degraded buffer;
• 15 snags and 11 logs will be installed in the degraded buffer; and
• Compost will be added around each of the installed plants in a circle 3 ft in
diameter and 3 inches (in) deep, and the site will be irrigated by way of a
permanent irrigation system (see Mitigation Reserves Program, Fee-In-Lieu
Worksheet).
MONITORING
The Proponent will monitor the on-site mitigation areas for at least three years following
installation in the summer.
The Proponent has included costs in the Mitigation Reserves Program, Fee-In-Lieu
Worksheet to allow for monitoring the off-site buffer for at least three years following
installation. The "fee-in-lieu" revenue that the County will receive in conjunction with this
Proposal constitutes the full extent of the Proponent's responsibility for monitoring
associated with the proposed buffer fill and subsequent mitigation efforts.
C:/Jobs/BCE/Cavalla/Fee In-Lieu Letter.doc
Chad Armour, LLC
3 05/16107
() ()
::,-:....:..
0, '--
Q. 0
)> g
~ ol g ()
C m _ .... 0
r "' r" ()~
~
CD
CD
3"
/-iii'
C
i a. g
...
§
~
-.J
Table 2 -Plant and Habitat Amenity Installation Guide
Total On-Site Buffer Off-Site Buffer
27 (6-8 ft; 11 ft oc
52 27 (6-8 ft; 11 ft oc
Douglas-fir 71 36 (6-8 ft; 11 ft oc
western red cedar 70 35 (6-8 ft; 11 ft oc
,Total Trees 245 125
Pacific ninebark 193
193
193
965
• 15,000 sf; to be enhanced on-site
' 14,500 sf; to be made up off site according to KKC 21A.24.137 Resource Mitigation Reserve
' total average density is 0.041 plants/sf
;,;~
-· 0)
::, "'
co " O::i,
0 < C (1) ::, ::, -c ::< (1)
:i: C/)
"'m ~m
-· X ::, -co ro -::,
0 "' :J o·
::,
§'; g,
~
0 ::,
:Q
"' ::,
;,;
ro
C/)
0
(1)
<
(1)
0
"O
3 ro
,l
162"• Avenue SE Extens·1on Mitigation Plan
King County, Washington
KBS Development
MAINTENANCE
The Proponent will maintain on-site mitigation area as follows:
• Remove weeds for three years after installation. Weeds include non-native
vegetation, particularly Himalayan blackberry, reed canarygrass (Phalaris
arundinacea), and evergreen blackberry (Rubus /aciniatus); and
• Replace trees and shrubs that die during the 3-year monitoring program to maintain
the minimum 80 percent survival rate.
The Proponent has included costs in the Mitigation Reserves Program, Fee-In-Lieu
Worksheet to allow for maintenance of the off-site buffer during the three year monitoring
program. The "fee-in-lieu" revenue that the County will receive in conjunction with this
Proposal constitutes the full extent of the Proponent's responsibility for maintenance
associated with the proposed buffer fill and subsequent mitigation efforts.
CONTINGENCY PLAN
If there is difficulty achieving the performance standards for the on-site mitigation, the
Proponent proposes to work with the County to develop a contingency plan.
Contingency plans can include, but are not limited to: regrading, additional plant
installation, erosion control, and plant substitutions of type, size, quantity, and location.
Such a contingency plan shall be submitted to the County by December 1st of any year
when deficiencies are discovered.
The Proponent has included costs in the Mitigation Reserves Program "Fee-In-Lieu
Worksheet" to allow for a contingency plan should deficiencies in the off-site buffer be
discovered during the three year monitoring program. The "fee-in-lieu" revenue that the
County will receive in conjunction with this Proposal constitutes the full extent of the
Proponent's responsibility for contingency measures associated with the proposed buffer
fill and subsequent mitigation efforts.
SCHEDULE
The Proponent anticipates executing this plan at the first available opportunity following
the receipt of the necessary approvals from the County. Assuming construction occurs
the summer of 2007, the first monitoring event will occur the following spring. For on-site
mitigation, the Proponent will submit a monitoring report to the County as indicated
previously. Maintenance will occur within four months following submission of the
monitoring report. Subsequent monitoring, reporting, and maintenance will follow the
same schedule during the subsequent years.
LIMITATIONS
Work for this project was performed, and this letter report prepared, in accordance with
generally accepted professional practices for the nature and conditions of the work
completed in the same or similar localities, at the time the work was performed. It is
intended for the exclusive use of KBS Development Corporation, Mr. Dave Petrie, Eagle
Creek Land Development, LLC, and their assigns for specific application to the
referenced property. This report is not meant to represent a legal opinion. No other
warranty, express or implied, is made.
C:/Jobs/BCE/Cavalla/Fee In-Lieu Letter.doc
Chad Armour, LLC
5 05/16/07
>
111-.; 11lp s1, s-
Drainage Questions for Neighbors Adjacent to and/or Downstream of Liberty Gardens
Name_-'-/i--"'/;'--.'~CJ'"'''-'?...,13..L..,i.:-=-..,_R.,_,_t __ /J1~,_·~Q~ff'-'-'R~-------Years At This Address '-15
Address /G 22 </ SE (4 l( S 7 !St: II/ T cl7,}' Vl( A,s;.I
1 Location
~
, Garage or outbuildings
Have you ev_er had water flow into an _ of the followi~n=: ______________________ _
] How deep is it? I Duration I
(days/weeks/months) , --1
Years
, (when did/does it happen)
I
[c:rawlspace or ba_s_e_m_e_n_t __ ~----_____ -------~------~-_____ --~
Have you ever had to use a pump to deal with the water? DYES or ,lefNo
DTemporary or OPermanent pump installation?
Do you have a french ditch/drain around your property to deal with runoff? A'fES or ONO
Do you have a trench ditch/drain around your foundation to deal with runoff? ~ES or ONO
Do you have any other improvements on your property to deal with runoff? )gYES or ONO
Do you have a mound type septic system because of drainage issues? DYES or );{No
Did King County require a mound type septic system because of drainage issues? DYES or )(NO
Have you ever had any issues with your septic system because of drainage or runoff issues? DYES or j\iNO
Do you ever have streams of water flowing across or into your property? J2!¥ES or ONO
If YES, please explain briefiy: __ c:e~~,~N--b ..... t:_--f,_-~e_· ~<2~U~[~:s~· l~»~E~-~~l~Y~B=§:~C'--5~j)~<!l_D~l:!..~~A-_' ~?t~'~D~---
3
Have you ever seen streams of water flowing across the road?~YES or ONO
Where?_~A~c~· 1~?_c'.J~5~5"t'f-':,_/~?".~f!_.s_-~/~, -----------------------
How Often? ________________ HowMuch? E,:\1 G V Gt./--To F"ill )/IS S'WIMM/rvG Poe,;__
Do you have any other concerns for the expected impacts from the Liberty Gardens subdivision? Or recommendations?
CARE -PO Box 2936 -Renton WA 98056 -highlands_neighbors@hotmail.com -206.888. 7152
•
Drainage Questions for Neighbors Adjacent to and/or Downstream of Liberty Gardens
Name_+R~~, -.D-+---~N~· ~/~h~UJ_,_; _p.J_/i __ __,__ _________ Years At This Address_/_! __
Address~/_(.;;_,, ~;l_S_'-/ __ 5_t__,_J_t/_'-/_J_~S~l--6=f~N-f_v~,,.) __ 9~U'~O :,_9 __ _
Have you ever had water flow into any of the following: rJ cJ
j Location
I
Years I How deep is it? I Duration ~j
________ ----+-(_w_h_e_n_did _l_d_o_e_s _it __ h_a_p_pe_n_) _____ ~_ _ (days/weeks/months)
II H_o_m_e _________ -,--___ ---------------i-------l------------_J
1
Garage or outbuildings I
---~---------~ ~rawlspace or basement --~
Have you ever had to use a pump to deal with the water? DYES or ~O
DTemporary or DPerrnanent pump installation?
Do you have a french ditch/drain around your property to deal with runoff? DYES or jJ!NO
Do you have a french ditch/drain around your foundation to deal with runoff? DYES or ONO
Do you have any other improvements on your property to deal with runoff? DYES or ONO
If YES, please explain briefiy: ______________________________ _
Do you have a mound type septic system because of drainage issues? DYES or MNO
Did King County require a mound type septic system because of drainage issues? DYES or ONO
Have you ever had any issues with your septic system because of drainage or runoff issues? DYES or ~NO
Do you ever have streams of water flowing across or into your property? DYES or ~NO
If YES, please explain briefly: _____________ ---------------------
Have you ever seen streams of water flowing across the road? DYES or ONO
Where? ---------------------------------------
How Often? How Much ? --------------------------------
Do you have any other concerns for the expected impacts from the Liberty Gardens subdivision? Or recommendations?
-fJ/£ !JJ?t/1 /,~ f\J!!'i PRtflJffE.o ~c)fZ 1J1v Lv'Clc't~£
;J;/
CARE -PO Box 2936 -Renton WA 98056 -highlands_neighbors@hotmail.com -206.888.7152
Drainage Questions for Neighbors Adjacent to and/or Downstream of Liberty Gardens
Lo.no do"
l
Address 14 2.o I lb"lw.. ~ 1'J C 5, '<-,
Have ou ever had water flow into any of the following:
I
Years At This Address JO ,;e.qr f
I
W"' 9~oS9
Location Years
(when did/does it happen)
' How deep is it? ! Duration
(days/weeks/months) I
,
Garage or outbuildings
I Crawlspace or basement
Have you ever had to use a pump to deal with the water? IEIYES or ONO
SITemporary or DPermanent pump installat/on? , ·. ,, . , ,Jr,~..,..
A-oOUJ ferlf'f..o..,u~+ .J),~,/'\ -lo n.4.14d't,,(_ L-->~
Do you have a trench ditch/drain around your property to deal with runoff? DYES or ONO
Do you have a french ditch/drain around your foundation to deal with runoff? DYES or· l:ifNO
Do you have any other improvements on your propedv to deal with runoff? (llYES or ONO Jc,,.1 i?vvirfy /1'1'4 ',!L ":5 p~J. 'I ;::~=dt d,~, -"
If YES, please explain briefly: 7er @c,o,i) Sy.>./,,,,,1 bft:, ,4.DtJt~ tf,,.,11.
/of-
It~,.; >e ot#, a ra.w( 5,jl<,e·e -f(,,J,,J.
Do you have a mound type septic system because of drainage issues? fll!YES or ONO
Did King Cour.t; require a mound type septic system because of drainage issues? 0YES or ONO
Have you ever had any issues with your septic system because of drainage or runoff issues? DYES or ~f.JO
Do you ever have streams of water flowing across or into your property? (!fYES or ONO
fo
lfYES,pleai;eexplaipbnefly:A-#t, rLvio•5 w11er 1>,f-Lile,-J ,1.J
-:fiAsta//"f/ e,ua.,/,?r ,1Aa In ... ,< "~ ,---/h f,u ..,+f-. c<"4' ertt.f <N"'"" t-/) i r--+ cf s v,., ~
7t,f $ofl(f. t,1,a,/er 5<.q,/lilf ouf-B>+ <JO, /U<Jr'h,_ #/,;,/<"'riv /,;,,e,
' r ' f
Have you ever seen streams of water flowing across the road? ll'IYES or ONO
•
Where? 8 crc,z) ,/J,I 'f J},i "'< 1,,,:,0,t ,vuR # gf--Pa.th way ;b Ll ~/1, /.Is
How Often? _,l-:1</~~'"'~"=· =11---~='°'=; "'"-'-':>.,_ ______ How Much ? _.,cg:LL/,.gHc,_...:_ ____________ _
Do you have any other concerns for the expected impacts from the Liberty Gardens subdivision? Or recommendations?
{µouf) (;/4 )o 5t.e ~~oA ,;}/'c..,p..5, {/15{c._f{~ e,;1.
{r.o,,Ju/1 profedy /, ~I'::,,
CARE -PO Box 2936-Renton WA 98056-highlands_neighbors@hotmaiLcom-206.888.7152
RE: CARE Update: Please send in your statement of
support!
~:o Mike Ritchey (mike-ritchey@comcast.net)
SentSun 12/16/07 2:49 PM
T . 'Highlands 0
· Neighbors' (highlands_neighbors@hotmail.com)
You have our full support We live at 14225 164th Ave SE to the south of the Liberty ball fields. There is
5 acres to our north that they want to develop and we are very concerned for traffic and water run off. A
number of years ago they made an attempt to develop the acreage and in doing so caused the water
flows to change and ourselves and neighbors had water under our homes. None had water pnor to the
skinning of the lots.
We are also very concerned about pushing 164th Ave SE through and the increased amount of traffic.
We have lived in our home since we built it in 1990. We get a lot of traffic during the ball season when
people park and walk into the Liberty ball fields. The parking in front of our home and neighbors leads to
the dumping of ash trays, garbage and the blocking of the mail boxes for deliveries
It would be very nice if the developments left a green belt from the exiting homes to help protect the
wildlife and preserve our views of a rural environment
Mike Ritchey
Windows Live Hotmail Print Message
RE: Liberty Gardens
From: Highlands Neighbors (highlands_neighbors@hotmail.com)
Sent: Wed 9/17/08 2:40 PM
To: rtimmons@ci.renton.wa.us
Cc: Jennifer Henning Uhenning@ci.renton.wa.us)
Page I of3
Attachments: t~~
AquiferRecharge_LibertyGardens.pdf (158.0 KB). HPIM3747.JPG (477.3 KB), HPIM3748.JPG
(531.0 KB), HPIM3749.JPG (541.6 KB), HPIM3752.JPG (500 6 KB), Contours_LibertyGardens pdf (98.1
KB), HPIM3803.JPG (506.3 KB), HPIM3802.JPG (380.2 KB), HPIM3745.JPG (5524 KB),
Ritchey_StreambedAtBackOfProperty.JPG (594.0 KB), HPIM4179.JPG (534.4 KB), HPIM4180.JPG
(534.3 KB)
Hello All!
With this email I am submitting photos a brief comments in regard to the Liberty Garden subdivision
application. The applicant has presented no data or other acknowledgement that there is currently a seasonal
stream that exits the project site on the south east. The stream bed leaves the project site slight west of the
junction of the 2 parcels to its south -1457500154and 14s1soo160. The general stream path can be inferred
from the contour lines in the attached Contour map as well.
HPIM3747.JPG Streambed flowing off (south) the Liberty Gardens parcel.
HPIM3748.JPG Makeshift bridge over streambed flowing off (south) the Liberty Gardens parcel.
HPIM3749.JPG view from footbridge to kids' treehouse.
HPIM3752.JPG Streambed at base of treehouse tree.
HPIM3803.JPG Streambed on the parcel behind (west) of the Ritchey parcel just before it flows onto Ritchey
parcel.
HPIM3802.JPG Streambed on the parcel behind (west) of the Ritchey parcel just before it flows onto Ritchey
parcel.
HPIM3745.JPG Streambed on the parcel behind (west) of the Ritchey parcel just before it flows onto Ritchey
parcel.
Ritchey _StreambedAtBackOfProperty.JPG Streambed along the back of the Ritchey parcel.
HPIM4179.JPG and HPIM4180.JPG show the drainage ditch on the west side of 164th AVE SE where the
water from the stream infiltrates. Water does not travel down this ditch to 144th. Instead. it infiltrates. This
makes sense when you see the IMAP pages. This area of infiltration is inside the Aquifer Recharge Zone and
the soil type changes from Alderwood on the Liberty Gardens site to Everett to the south of the site.
We believe that the drainage system that the applicant has proposed has not addressed the existence of this
stream at all and that construction of the stormwater system as proposed would be an inappropriate
diversion of this stream from its natural discharge. If the system is to be approved as proposed, we believe
that a stormwater variance is required to be approved before the Plat Hearing.
Please let us know if we may assist in your investigation and evaluation of this matter. We would be happy to
arrange meetings with the neighbors who would be most affected by this stream and its diversion.
Thank you for your time and consideration,
Gwendolyn High
C.A.R.E. -Community Alliance to Reach Out & Engage
http:! /bl I 40w.blul 40.mail.livc.com/mail/PrintShell.aspx?type=mcssage&cpids=3a5daetb-... 3/10/2009
HP IM4180.JPG
HPIM3 7 48.J PG
HP IM375 2 .JPG
HPIM3803.JPG
iMAP
The information included on this map has been compiled by King County siaff from a variety of sources and is subject to change without notice. K ing
County makes no representations or warTanties , express or implied, as to accuracy, completeness , timeliness, or rights to the use of such informatk>n. ti1
This document is not intended for use as a survey product King County shall not be liable for any general, special, indirect. incidental, or consequential ... K·1ng County
damages including, but not limited to, lost revenues or lost profits resulting from the use or misuse of the infonnation contained on this map. Any sale of
this map or information on this map is prohibited exoept by written pem,ission of King County.
Date: 9/17/2008 Source: King County IMAP -Groundwater Program (http://www.melrokc.gov/GIS/iMAP)
• • ..
Groundwater Sources
I County Bo u ndary 1•
T M:.:,untain Peak.s
CJ
K;ghways
King County Water Resource
Inventory Areas
iMAP
Le g end
Streets
Parcels
D Lakes and Large Rivers
• 1 Streams /V
•'
Cribr.al Aquifer Recharge Area
[cont)
C~·2
C~·)
j'/ lncotporated Ama
Shaded Relief
The lnrormation included on this map has been compiled by King County staff from a variety of sources and Is subject to change without notice. King
County makes no representations °' waminues , express or implied , as to accuracy. completeness, time,ness, °' rights to the use of such information.
This document la not intended ror use as a survey product. King County shall not be liable fe< any general, Special, indirect, incidental,°' consequential ~-K"1ng County
damages including, but not limited to, lost revenues°' lost profits resulUng from the use or misuse of the inrormation contained on this map. Any sale of
this map°' information on this map Is prohibited except by written permission or King County.
Date: 9/17/2008 Sourc.e: King County IMAP· GroundWater Program (http://Www.metrokc.gov/Gi SliMAP)
iMAP
Legend
I Co unty Boundary ,. Streets j4/ Incorporated A.tea
Contou rs (5ft dait)
;/ 1oom.1coo
;./ O,,cy
CJ
Highways
K ing County Waler Resource
l nvenlo,y Areas
COMM ENTS: Contours
Parcels
D Lake s and Larg e Rivers
Streams
The information included on this map has been compiled by King County staff from a variety of sources and is subject to change without notioe. King
County makes no representations or warranties, express or implied, as to accuracy, oompletene ss, timeUness, or rights lo the use of such information.
This document is not intended for use as a survey product. King County shall not be liable for any general, special, indirect, incidental, or consequential
damages including, but oot limited to, lost revenues or lost profits resulting from the use or misuse of the lnfomlation contained on this map. Arry sale of
this map or information on this map is prohibited exoept by written permission of Kin g County.
Date: 9/1712008 Source: K ing County iMAP-Groundwater Program (http://www.metrokc.gov/GIS/iMAP)
ti King County
Page I of2
Ortiz, Cathy
From: Langley, Kristen
Sent: Monday, February 11, 2008 9:38 AM
To: Nolan, Matthew; Mitchell, Mark-C; Chang, Kevin; Posey, Norton
Cc: Norman, Paulette; Perrin, Henry; Eichelsdoerfer, Robert; Gualtieri, David
Subject: RE: Urgent -Arterial Review
My remaining recommendation (some were subsequently annexed) is simply based upon the RRE permit
I did weigh in on the recommendation for SE 192nd (#1) based upon volumes that we've seen on plat-generated
TIAs.
Re: Henry's #15. A four-block-long arterial doesn't seem appropriate. If there is going to be a change to 'arterial', I
would recommend that the easterly limit of #15 be extended to 168th Avenue SE --where SE 136th 'picks-up'
again as an (on the adopted map) arterial. Much of the right-of-way already exists, and, based upon the past 4 or
5 plats in the area, the TIAs suggest that it is a "natural" to have a neighborhood collector to service intra-
neighborhood (and neighborhood-to-school) trips paralleling SE 128th.
SE 144th St
w
(/)
Henry's #15 and #16 are in black. IF we're considering it, the arterial classification for SE 136th should be
extended as shown in "fuchsia-ish."
I don't know that we would be seeing arterial volumes(> 2500 ADT, or so) for SE 136th. But, there's limited
additional development potential of some of the large lots (circa 1910 5-acre tracts) that abut both 160th and
162nd. East of 162nd, there aren't very many large parcels capable of resubdivision.
Re: 51st (#6) ... S 288th to S 305th is now inside the City of Auburn.
Kristen Langley
Senior Engineer, Traffic Impacts and Data Analysis Unit
KCDOT/ Traffic Engineering
206 263-6102 (Seattle)
206 296-7155 (ODES-Renton)
206 296-0176 (fax Seattle) 206 296-6613 (fax Renton)
06/03/2008
Effective October 2007, my email address will be changing to kristen.langley@kingcounty.gov
From: Nolan, Matthew
Sent: Monday, February 11, 2008 8:48 AM
To: Mitchell, Mark-C; Chang, Kevin; Posey, Norton
Cc: Norman, Paulette; Perrin, Henry; Langley, Kristen; Eichelsdoerfer, Robert; Gualtieri, David
Subject: FW: Urgent -Arterial Review
Importance: High
Mark, Kevin, Falin, Norton
Page 2 of2
I want to make sure you are ok. with the changes proposed to the arterial network shown on the attached map
and list. There are some significant changes from a public perception standpoint, including changing 160th Ave
SE to an arterial and SE 208th from an arterial to a local street. Both of these have active citizens who have
emailed us many times.
In talking with Dave G this morning he attributed many of the changes to Traffic Engineering requests. I not sure
if these were viewed as formal requests or just items which Planning should consider. Do you know if local land
use, traffic counts, collision history, and road geometrics were formally considered for these changes?
Thanks Matt
From: Lindwall, Jennifer
Sent: Friday, February 08, 2008 2:55 PM
To: Nolan, Matthew; Norman, Paulette
Cc: Gualtieri, David; Osterhoudt, Sue
Subject: Urgent -Arterial Review
Importance: High
Paulette & Matt,
I apologize for the super late and super urgent e-mail.
David Gualtieri worked with staff in Traffic to review the attached changes. It was his expectation that they were
running this through you. However, it now appears to us you've not seen these proposed changes, most of which
were proposed by your staff.
This is all part of the Comp Plan and therefore is due today (literally!). So, if you could take some time first thing
on Monday to review, this is about our only opportunity to make changes. DG needs to finalize this and get it to
print ASAP.
thanks I Let me know if you have any questions, as soon as possible.
Jennifer
06/03/2008
From:smith5124@aim.com
~,ent Sun 12/16/07 7:04 PM
1 o highlands_neighbors@hotmail.com
I doL't know about 156th, but I was hit at the ~ntersection of 136th
and 158th. We we;::-e heading west towards 156th when a gal come from our
left and hit us. That was Jan. 3rd before the stop signs were put up on
136th. We a~most got hit there again last week when so!neone blE"w'
through the si:op sjgn. Be very careful ::here!
.2c·,.Z
. o ::< ---J,f..,0/1
. <'/ ,; .
i.
IC
i
F1 /~ / "'.2.,
('· ~I
TRAFFIC ENGINEERING SECTION
Speed Summary Report File# 08-9143 £ 5 c,..,,.
~ .... _______ 1_5B_AV_E_S_,,E_so_u_th...,.o_f_S_E_1_2_8-'S.,..T....,... _______ _..j ~\".'
Analysis Performed 4/812008 by Randy Westendorf \. 1 • .
Date
Time
Direction of Travel
Legal Speed Limit
Average Speed
85th Percentile Speed
. AM l'eal<.flour
AM Peak Hour Volume
PM Peak Hour
PM Peak Hour Volume
Percent 10 mph Over
Percent 15 mph Over
Traffic Volume (ADT)
Date
Time
Direction of Travel
Legal Speed Limit I Average Speed
85th Percentile Speed I AM Peak Hour
I AM Peak Hour Volume I PM Peak Hour
PM Peak Hour Volume
Percent 10 mph Over
l Percent 15 mph Over
Traffic Volume IADTI
---·
100.00
90.00
~ 80.00
0
C
' • 70.00 &
I ~ 60.00 u.
"'
-r 4/1/2008 I , 4/2/2008 l'rt-4/3/2008 ~ 4/4/2008
1300 to 2400 0000to2400 OOOOto 2400 0000 to 1300
Day 1 Day2 Da ,3 . Day4 Day5 ·
North South North South North South North South North South
25 25 25 25 25 25 25 25 25 25
26.2 28.1 24 26.1 27.1 ,·: <28.3 27 27.1
34.9 35.1 33 35 . 35.1 35 34.9 35
0100-0aao 0800-0900 0700-0800 1100-12ao 060Q..0700 0700-0800 -.... ----
"l -'(l'V ... 4-:i'f-28 12 28 7 24 10
15()0..1600 1600-1700 1500-1600 1600,-1700 1400-1500 1700.1800 1200-1300 1200-1300
12 30 15 28 16 38 1 3
18% 21% 12% .19~ 19'.'fo 19% 16% 18%
1% 2%.
. 2% 2°io' 3% 2% 2% 2%
78 154 199 203 203 202 113 51
' ~~..Ji?:, HL()':2_ '"C>'J Daily Averages
. . 10<+ on
Day6 Day 7 Daya 3 (24 Hour Days)
North South North South North South North South Both
25 25 25 25 -~ L~ 25 25 25 25
26 27.4 I 26.7
34.4 35.1 I 34.7
I
----~ i . ' ---· -:' 16% /'lfY'/o I (18% ' • ('=""2% ---V -')rif----....t '-?2'\F) '-nn, ... '--iu:i i 401·-. .
' Accumulative Speed Distribution Curve I -e -15% ~meed I ~50"/., soeed i -*"' 85%speed '
---.£::::-.....:~. -' i i ----i
( 34?.~.-_)
------------------,-------i
-! I ---1 ·-· .. . ---i--I . i I ., ··--------.. --------------,------
I : -. ---------· --------
28.27 • '
?ZJ7
l .rst
3o
'-lo
ff-{)
.:?.. C
I '3,, C
?<,'-1.,
I; • 50.00 ----------I --------------___ , __ ,. ________ ··-"' j i -" 40.00 ' " ' '
. ----!~ -,-·---".------i-----; ---I l E I ' " 30.00 i 0 i -----·---. --. . .. -----------.
! 0
I "' 20.00 ----· ---·--'-··-;;s:-S-s ---------·------•
H ' I 10.00 .. ---·--J_ ____ ---• -----·-··------------------------t--·-· : ' . : 0.00
0 10 20 30 40 50 GO 70 80 I "· Miles Per Hour .i...r
t C
4-0 ~ ; c.r;.AO ckk Is IMf4 /.,; t. 1/c. -L. '2;,c' Le:UA ~ lo ~l-t(:3,
/~.3 ~~-~-
---·:,-
King County
Road Sen,lces Division
Ikpartment ofTransportation
201 SouthJackson Street
Scat1lc, \.'tVI. '98104-3856
April 9, 2008
~ . Helga Jaques
131 I4-158th Avenue SE
R4'ton, WA 98059 j ..
RH: Neighborhood Tia.•fi.CSafety
Dear Ms. Jaques:
. fvu_A ltt-10 1 1 l,v , n., , rt-<_/
J!eC-;, "v!.,,;;f · c c<-f:J'~:"L.C_ c....,.~ .4_,__ ~
-~~~
I r--1./
-7 t: ·0,;~~~-
1 ! "" r-!
Thank you for contacting the Traffic Engineering Section about your concerns for traffic safety
in your neighborhood. The King County Department of Transportation shares your concerns
about the impact of vehicular traffic on residential neighborhoods and is working jointly with
the King County Police to improve residential traffic safety.
The enclosed brochures provide ways in which you and your family, friends and neighbors can
contribute to traffic safety. These brochures contain suggestions and tips which you may adopt,
as well as telephone numbers for your convenience in obtaining assistance from the Department
of Transportation and the King County Sheriff's Office. ·
..
Thank you for your inquiry. If you have any questions or additional concerns, please do not .J .
hesitate to contact me at (206) 263-6125. -~
Sincerely
I
'
Enclosures i
cc: Sheriff's Office, Special Operations Section
ATTN: Neighborhood Traffic Safety Coordinator
/"!(-/',">_. ---··
lclntsp\packletl .doc
2 3 ;:?.
1·c1 q
4-31
.Jq ';> '
&ts If
f.c ·,. l.f
;Z O;,
8'3 7
AO.a_
I o3C(
l l 3
I s-:z.
C;-r
I .,, 0...., 'X ( ) ( _, " ,· l'.,.-(,l.-7.~ · I ,<.. ;;, ~, V
r.)',..1-(-l "'-'1'..
u-i 'f ~,<)
? 5;-i, ,,.J,4.-t.. ~v"·"<!..t')' ~
~ I o "'-1 r, t.,_ ,ri e\.-u/\..-l.
.:Z.. '5 ~ 'f-0 ""-"¥ L--t ( l -r '61<!..L.... :z. 't-
l ",., ~ ;,, .....,.., h '(_ /0 #~7.J
" ··----
. . '
(<UL.M4f~
~; ~~~
IJ~~
f y;1
ie udiJ. lA.A..;,_ .. · 6-~ u-t. ~ -y~ .. $-~
y/, ~.. ~ ' {,~ ·~. ~ 'ti,,, •
-·v
-\ t~{lut l,·o.4 ~ // . . . /./.c.-~ [;,, /.relLd--=~
~·· w ~ "' fl I<: , {J.;, !//JJ J~()
.. ------~-------,
(
-1
··:i·
-~,--~
-zlf ~ _7~-----__ -
-----~ /1.A~~{
2oc;
--=~~--&e--
JV---,~
-----------,---~-
..... ··
'
Windows Live Hotmail Print Message
D Windows Live-
FW: CARE Update: Liberty Gardens -Progress Today!
From: Highlands Neighbors (highlands_neighbors@hotmail.com)
Sent: Tue 7/22/08 8:54 AM
To: highlands_neighbors@hotmail.com
From: mrseversonl@msn.com
To: highlands_neighbors@hotmail.com
Subject: RE: CARE Update: Liberty Gardens -Progress Today!
Date: Mon, 21 Jul 2008 11:05:56 -0700
Page I of I
Which traffic engineers are you dealing with. We independently dealt with Wes Harvey on our
traffic concerns and had a speed trailer installed for traffic coming from 136 up 158. The average
speed we visually noted was 40 miles an hour in our 25 zone.
People see the straightaway and speed up. We have 15 children (most under 7 years of age)
between 130th and 132nd. Speed here over 25 mph is NOT acceptable.
We have observed personally, traffic turning onto 158th going north from both east (from 16oth
direction) and west (from 156th direction) entering 158th north and heading in a beeline for SE
128th without stopping any where along the way.
We decided not to have a speed trailor in the opposite direction (south on 158th), and have opted
to request the traffic counters again in October.
The results of the first traffic counters we requested on 4/1 to 4/4 (Monday-Thursday) showed that
1,203 cars padssed by us with 153 over the speed limit by 10 mph or more; 23 over 40 mph and
130 over 35 mph.
When we called to see about traffic signs or bumps or round abouts we were told we had to
average 500 cars per day or more to qualify for any option.
Further we were told that neighbors would have to pay for changes to the roadway caused by the
impact of modifications (i.e. storm drains to accommodate the modifications).
In addition we were told that Children at Play signs were no longer posted throughout the county
by order of the King County Prosecutor. It seems a driver had sued the county for such signs
claiming that he hit a child because he was distracted by the sign and he won the case. Only
schools who have a live traffic guard can post signs. Private citizens who post the green children
at play signs are now classified as defendent parents and subject to law suits for collection against
them, not the driver.
http:/ /bl 140w. blu 140 .mail.live.com/mail/PrintShell .aspx ?type=rnessage&cpids=ccOaceca-... 7/22/2008
Bruce Whittaker 1/8/2007
Cavalla L06POOO 1-Rescreening Comments
Drainage:
The submitted conceptual offsite road improvement plan for 162nd Ave SE shows a 15-
inch downstream pipe system vs 18-inch originally shown. The downstream system
appears to have limited capacity compared to the upstream pipe system. Please provide
Level 3 Flow Control for proposed drainage systems or other alternatives per Core
Requirement 2 of the KCSWDM. The alternatives could be to provide a Level 3
Downstream Analysis and propose downstream improvements for adequate
mitigation(sce Table 1.2.3.A on page 1-29 KCSWDM).
Please provide an analysis and estimate of compensating storage required for the existing
depression north of the SE 1441h ST cross culvert.
Revise the conceptual drainage plan to include any compensating storage , Level 3 Flow
Control or other revisions necessary.
Please revise the conceptual drainage plan to address 3: I length to width ratio for the
water quality design of the facilities. Note that baffles cannot be used to obtain 3:1 per
Section 6.4.1.2 p6. 6-73 of the KCSWDM.
R-...._..,v..,._b ~ ~l:s / oD-t ~1 .J..,e
R~J
'"'-., , ~ 0 -f' , O""-J.__ o--4' ~ l +_ :"
'"2-2-' L.J....:., ~ ~ ~ , .le eAo~~ 0 1
'
Cr,+,~~-;;,
' C. a,,_..,..__-\ ..5 .,,---o...J,. ..,_ \ "'-~ -s::-\--~
n_eed.5 ~o""._CQ__ use_ ~a--o~
Whittaker, Bruce
To:
Cc:
Subject:
Tibbits, Chad
Langley, Kristen; Gillen, Nick; Claussen, Kimberly
Cava Ila L06P0001: ReScreening Issues
Attachments: CavallaRscr.doc
Chad,
I spoke to Steve Foley this AM and have incorporated his comments into the attached.
Page I of I
Please note that the offsite proposal to open 162nd Ave SE, and therefore the whole subdivision feasibility may
not work unless Nick agrees to mitigation. I think we should include words to that effect in the letter, if you have to
send out a letter.
Thanks,
Bruce Whittaker
01/08/2007
Langley, Kristen
From:
Sent:
To:
Cc:
Subject:
Gillen, Nick
Thursday, July 26, 2007 1 :25 PM
Tibbits, Chad
Whittaker, Bruce; Langley. Kristen
RE: L06P0001
As far as the plat itself, I could write some conditions. They have some conceptual mitigation plans that are acceptable for
prelim approval. The biggy is the off site road improvements. It was my understanding that we are going to ask for a
revision (road built to road standards). This may necessitate the need to culvert all or portions of the stream witch would
mean more impacts and additional "conceptual" mitigation. Is that your understanding?
N
From:
Sent:
To:
Subject:
Hi Nick,
Tibbits, Chad
Thursday, July 26, 2007 1:00 PM
Gillen, Nick
L06POOOI
Just a reminder for comments on the Cavalla Plat we met on earlier in the week.
Thanks,
Chad
Page 1 of2
Langley, Kristen
From: Foley, Steve
Sent: Wednesday, July 25, 2007 9:49 AM
To: Whittaker, Bruce
Cc: Langley, Kristen
Subject: RE: Cavalla Plat L06P0001
Bruce, now that I have had a chance to look this over I have a clearer picture. Big changes for this neighborhood. As
always, Ed has done a great job of analysis and narration. I have not looked at the modeling, but the figures and text are
very clear. I will be down there tomorrow and I could meet before 10 or after lunch. Since so much of this relates to road
fiooding and road improvements, it would be good to include Kris in the discussion. Would this work for you two?
From: Whittaker, Bruce
Sent: Wednesday, July 25, 2007 8:32 AM
To: Foley, Steve
Cc: Langley, Kristen
Subject: RE: Cavalla Plat L06P0001
Steve,
The plan is to open 162nd Ave SE from SE 144th St to the north. This would then open the 162nd corridor, giving the
developments a new connection out to SE 144th St. The neighborhood has limited access points out, including a
challenging existing northerly connection at SE 128th St/ 160th Ave SE.(bad sight distance). We looked at a possible new
east connection on SE 136th St, but a section of the corridor is not county R/W and the owner is adverse to the idea.
The conceptual road/drainage plan submitted shows opening the 162nd Ave SE corridor north of SE 144th St. This
means eliminating the existing " ponding area " and likely tightlining the existing feature. I think that would be good news
for Don Gregg and the other drainage complainants along that corridor.
Anyhow, take a look at the Level 3 Analysis and then we should discuss this soon.
Thanks,
Bruce W
From: Foley, Steve
Sent: Tuesday, July 24, 2007 3:49 PM
To: Whittaker, Bruce
Cc: Tibbits, Chad; Sleight, Brian; Gillen, Nick; Langley, Kristen
Subject: RE: Cavalla Plat L06P0001
Bruce, I took a quick look at the Level 3 report and clearly I will need to spend some time on it. A couple of things come to
mind immediately-one, is there any chance that 152nd Avenue NE will ever be opened north of 144th Street? Second, if
the county were to consider a capital project on SE 144th, the size, cost and complexity suggest that it would probably
take years before it could be built. Allowing or requiring these developments to contribute to an uncertain GIP is always
problematic. What is your guess as to when these projects would be going to hearing? We would need to do GIP
scoping before then. It sounds like the existing problem is really a Roads flooding problem, not one WLRD would take
on. If we were to do a GIP here it looks like it would be a large CIP, not an NDAP. Some more limited downstream
improvement by the developers might make more sense than an uncertain KC project. I tend to favor a downstream fix if
feasible rather than just doing Level 3 flow control.
Interesting about the 144th "under drain culvert" design. That is quite unusual.
01/30/2008
I will spend more time on this, then we can discuss. --Steve
From: Whittaker, Bruce
Sent: Tuesday, July 24, 2007 1:03 PM
To: Foley, Steve
Cc: Tibbits, Chad; Sleight, Brian; Gillen, Nick; Langley, Kristen
Subject: RE: Cavalla Plat L06P0001
Steve,
Page 2 of2
Thanks Steve. At this point we are asking for a revised conceptual drainage/road plan for the 162nd Ave SE offsite road
design. We think that in order to provide an adequate shoulder on the west side of 162nd, the existing feature will likely
have to be tightlined. The design should include Level 3 Flow Control(or other proposed mitigation) per Ed McCarthy's
Level 3 Offsite Analysis. I am also asking for an analysis of any required compensating storage(if any) for the existing
"ponding area" at 162nd and SE 144 th St. I am also asking for a cage type overflow connection for the east-west swale
connection to 162nd Ave SE.
I obtained a copy of the county design plans for the road construction on SE 144th St, west of 162nd Ave SE(as built in
1984). The plans call for an "under drain culvert" all along the south portion of the improvement. The pipe callout is 18-
inch with perforated holes in the !QQ of the pipe. It appears that the design was meant to let subsurface water into the
conveyance culvert, rather than out of the culvert for infiltration.
Anyhow, I am thinking that the Level 3 Flow Control is satisfactory mitigation for the problems found in Ed's Analysis. He
did suggest some possible future project that the county might want to evaluate and construct. Maybe Brian Sleight would
be interested in this in the future.
At the very least, I think Ed's Analysis does accurately show the existing conveyance, and potential capacity problems.
I would appreciate your input on the mitigation for this project. Do you think Level 3 Flow Control is adequate? A,ny other
comments are welcome!
Thanks,
Bruce Whittaker
From: Foley, Steve
Sent: Thursday, July 19, 2007 3:06 PM
To: Whittaker, Bruce
Cc: Tibbits, Chad
Subject: Cavalla Plat L06P0001
Bruce, I got the update package for Cavalla. Please let me know if you need anything from me on this. --Steve
Steve Foley, Engineer Ill
King County Water and Land Resources Division
201 S Jackson Street, Suite 600
Seattle, WA 98104-3855
206-296-1973
FAX 206-296-0192
Note new email address: ste_y_e_,_f9leyf~-kingcounJ:y.gov
01/30/2008
Ortiz, Cathy
From:
Sent:
To:
Cc:
Subject:
Langley, Kristen
Monday, February 25, 2008 9:18 AM
Nolan, Matthew; Comfort, Craig
Kara, Fatin
Page 1 of7
RE: Public Disclosure Request: All records related to Road Variance for ODES file Numbers
L05P0026,
Attachments: L05P0026 RPT.doc
It would appear to me at first review the issues of concern to the "CARE " advocacy group are issues of land use
not road variance. I would assume rnany of these issues were considered by the Hearing Examiner.
They were, Matt. My testimony: direct, in response to Ms. High's line of questioning, and in my rebuttal, in the
hearing was extensive. The Examiner's decision is attached. He did not make any findings overruling staff on that
issue, and disagreed with us (on school walkways) on one point --and added a condition of approval related to a
walkway to the elementary school located east of the subject subdivision. We had a different route incorporated
into our recommendation, so, it wasn't something that we 'missed'.
The consultant PE (D. Balmelli at Barghausen) for another plat (Cavalla, and later for plats of both "Cavalla" and
"Liberty Gardens") took the lead on a conceptual plan/profile for this off-site extension of 162nd Avenue
Southeast, and has submitted a preliminary plan/profile (to establish feasibility, and give us something to look at
to give some initial feedback of critical area impacts ... stormwater facilities ... grading ... road widths and shoulder
treatment, etc.) even though Barghausen's clients aren't even ready to have a plat hearing scheduled. The
improvements are proposed to be constructed within right-of-way conveyed to the County with a plat recorded in
1907 -which, from our perspective, established the location of the intersection of SE 144th/162nd.
In the 1960s --so, 50+ years after the dedication of 162nd Avenue SE --two other subdivisions established their
own access locations (offset from 162nd) off of SE 144th --one of the two plats, in fact, was required to dedicate
one of the SE 144th/162nd SE intersection property line radii. This one was not required to improve 162nd
Avenue SE across its subdivision boundary.
The alignment proposed by Barghausen, with this first submittal, has a sag vertical curve shortly before its
intersection wrth SE 144th that may be shorter than KCRS in order to provide a KCRS-compliant intersection
landing. The road profile may change to lengthen the sag curve, but, my testimony in the hearing was that
roadway illumination is a common means of addressing sag curve issues.
The proposal at this point is that the off-site portions of 162nd Avenue SE will be constructed to something greater
than the half-street standard (KCRS 2.07). Our point to the applicants, and their engineers (Barghausen, as noted
--and Baima & Holmburg for the Threadgill plat) was that, within the existing 60-foot right-of-way, these off-site
improvements have to have a minimum of 22-feet of paved width, curb/gutter/sidewalk on one [east] side (for
pedestrians and to control stormwater). The half-street standard is limited to serving as primary access to "35
lots", and, my assessment has come up with approximately 40 -45 trip-ends use the off-site section of roadway in
the PM peak hour.
So, we acknowledge that the criteria for half-street isn't appropriate, and have established (already, in the case of
the SEPA for Threadgill) that the cumulative impact of the pending applications require something greater than
half-street, but, the volumes don't rise to 'full-width' as an offsite (KCRS 1.03A). Ms High believes, if I recall, that
doing something less than full-width required a Variance. However, this appears to the STC to be an issue of
KCRS 1.03A (extent of off-sites), and something greater than the minimum in KCRS 3.07 has already been
required under SEPA (for Threadgill).
Ms. High, in testimony, argued that other properties could come in --in the future --that would impact 162nd
Avenue SE. I didn't disagree in my rebuttal, but pointed out that --if they did --even the roadway improvements
proposed in this preliminary road improvement plan are capable of being expanded-upon (additional widening,
and construction of the [west] second curb/gutter/sidewalk) by those 'speculative --at this time', but possible,
06/03/2008
Page 2 of7
subdivisions. Further, that they also abut 160th Avenue SE (paralleling), and have potential trip distributions via
an east-west roadway --so, simply adding up all of the future development in the area doesn't apply to a
determination of the 'number of lots primarily served' by 162nd.
A full 60-foot right-of-way exists ...
(in fact, has existed for just over one century now --and isn't, after consultation with Ray Flo rent, subject to the
early 20th Century Ballenger (sp?) Act provisions.)
... so, it is feasible to construct, and widen by these future plats. And the potential nexus, in any event, for these
"speculative" subdivisions, even absent a direct impact, is that it is a walking route for school-age pedestrians to
the local middle school.
The school district, at this time, has not provided any additional information in the 13 months since their last
correspondence that suggests that they are pursuing the acquisition of portions of the Cavalla plat --noted in
CARE's emailed attachments --for an off-site parking area. I've heard second-hand that the Applicant isn't
interested in selling to the ISO, so, the District, if they were still interested, would appear to have to go to
condemnation. Even if they were successful, it would change the fundamental assumptions of the TIAs prepared
to date --and, they (the District) could reasonably be expected to be responsible (ODES, if still in the
unincorporated area) for some of these off-site improvements to 162nd Avenue SE, and, might have to construct
widening above and beyond the minimum 22-feet already contemplated.
Kristen Langley
Senior Engineer, Traffic Impacts and Data Analysis Unit
KC DOT/ Traffic Engineering
206 263-6102 (Seattle}
206 296-7155 (DOES --Renton)
206 296-0176 (fax Seattle} 206 296-6613 (fax Renton)
Effective October 2007, my email address will be changing to kristen.langley@kingcounty.gov
From: Nolan, Matthew
Sent: Monday, February 25, 2008 8:04 AM
To: Langley, Kristen; Comfort, Craig
Cc: Kara, Fatin
Subject: FW: Public Disclosure Request: All records related to Road Variance for ODES file Numbers L05P0026,
Kris, Craig
Sorry about the large file. It would appear to me at first review the issues of concern to the "CARE " advocacy
group are issues of land use not road variance. I would assume many of these issues were considered by the
Hearing Examiner. But regardless I would like to understand this issues better maybe we can discuss this at ar
upcoming variance meeting.
Thanks Matt
From: Norman, Paulette
Sent: Monday, February 25, 2008 7:56 AM
To: Nolan, Matthew
Subject: FW: Public Disclosure Request: All records related to Road Variance for DDES file Numbers L05P0026,
FYI
06/03/2008
Page 1 of7
Ortiz, Cathy
From: Langley, Kristen
Sent: Thursday, February 28, 2008 10 35 AM
To: Norman, Paulette; Nolan, Matthew
Cc: Kara, Falin
Subject: RE: Public Disclosure Request: DOES file Numbers L04P0034 and L06P001
Paulette:
I'm out of the office, at home, ill, today. I'm checking emails (smile) obviously.
I can give you and Matt a brief run-down. I've provided some of the background to Falin, and I recall some
discussion with Matt --back before the briefing with the PAO on the Battleground case --already, re: some of the
issues surrounding the construction of off-site improvements to 162nd Avenue SE (the 60' right-of-way for which
was dedicated to the County in 1907, after some research of the plat maps and discusions with Ray Floren!) from
the southerly frontage of the Liberty Gardens subdivision (in review, due to the on-going right-of-way vacation
petition appeal for 16<\th Avenue SE), to the existing SE 144th Street.
Liberty Gardens (L04P0034) and the plat of Cavalla (L06P0001) are proposed at the southerly end of the current
paved roadway. The distance from the frontage of either of the two plats, to the point where there are two routes
available for vehicular traffic, exceeds 1000 feet. To the east of the two plats exist the Liberty High School and (2)
Parks propery (Maplewood Park, I believe). The west, directly opposite the two, exist some remaining large acre
tracts created by a plat in the early 1900s. The nearest east-west connection for these two, nearby, and currentlv,
is SE 136th.
The STC looked at neighborhood circulation issues for the immediate area, including for the plat of Threadgill (L
05P0026 --now, with preliminary approval). Included in that review was the feasibility of extending the
improvements through the unimproved right-of-way to SE 144th Street. This right-of-way abutted two plats
recorded in the 1960s that were not required to improve the right-of-way (they abutted it). One (the one at what
was already the NW corner of the 144th/162nd Avenue SE rights-of-way) was required to dedicate a property
corner radius. That same plat (again, in the 1960s) had proposed a 0_ew access (161st, if I recall --since I don't
have my map in front of me) at, what would now be an intersection spacing less than the current standards under
the 2007KCRDCS (or, the 1993 --since all three are currently vested to that version).
In addition to providing an additional travel path for those project-generated trips (based upon Gary Norris' TIA)
that would otherwise have to travel through a HAL, and resolving a potential length of cul-de-sac matter, the
extension provides an improved (curb, gutter and sidewalk) walkway route for school-age pedestrians for all three
subdivisions: Liberty Gardens, Cavalla and Threadgill to the middle school in the area. To a lesser extent, the
extension appears to us to provide a convenient alternative route for the proposed projects' (plural) and some
existing development to another intersection (156th Avenue SE/SE 136th) that does not yet meet warrants for
signalization.
Based upon the extent of off-site improvements provision in the KCRS, and my own rather easily-determinable
reassignment of project trips (to determine the peak hour volumes that, instead of going north on 162nd --
currently, the only route available, would instead head south on the extension), and recognizing that the answer
was more than would be appropriate for a half-street (primary access to 35 lots or less), the ~TC recommended a
design criteria MINIMUM of 22-feet of paving (greater than the 20-foot "half-street" standard, therefore), plus
curb/gutter/sidewalk on one side (school pedestrians and to control stormwater), PLUS elimination of a potential
hazard (open stream course that parallels the roadway centerline --to be tightlined) on the opposite side of 162nd
from the Liberty Garden+Cavalla frontages.
The peak hour volumes with these permits don't rise to needing 'full-width' (32 feet) off-site improvements.
However, the tight-lining allows other future large-acre parcels (those, ironically, that were the tracts by which 162
nd Avenue SE was dedicated before WW1) --which abut, and may 'front' (depending upon those future
applicants' plans) --allows a reasobably -probability of construction of the additional roadway width: 10 feet, or, if
06/03/2008
Page 2 of7
Cavalla does change (see below), an appropriate increase in the initial width might become the SEPNplat
condition of approval --with a corresponding decrease in the remainder to be constructed in conjunction with the
currently-speculative, but potential, subdivisions located on the opposite side of 162nd from the Cavalla and
Liberty Gardens proposals.
The three parties: Liberty Gardens, Cavalla and Threadgill applicants, have executed a private agreement to fund
the construction of the off-site extension. This was done last year.
On a Comp Plan policy perspective, this is exactly the scenario anticipated in the Comp Plan policies that I
worked upon for the 2000 Comp Plan update (T-30_, --and paraphrasing): developing highly-connective grid-
based systems in conjunction with in-fill development in the Urban area, and extending improvements within
existing off-site rights-of-way when reasonably necessary to address impacts of the proposed project.
Barghausen prepared a preliminary design (introduced into the record at the Threadgill hearing, and noted as
being "PRELIMINARY") in response to the rescreening letters sent out in conjunction with the two plats that they
are working on: Liberty Garden and Cavalla. At this point in time, we're in a review cycle --rescreening letters out
to the customer, and awaiting responses back. Informally, I've been led to understand (verbal comments while
passing in the hall, only --no emails, telcons or other correspondence) from the assigned planner that the Cavalla
project may come back in with a change --and not in a manner that would reflect any successful discussions with
the Issaquah School District's letter (of Jan 2007, provided by Ms High) about acquisition of a portion of the
Cavalla site. Quite the contrary, apparently. However, until I see something in the formal resubmittal, is
speculative --only. It alone would necessitate an update to the TIA, prepared by G. Norris, however.
I can provide more detail. Some of what has occurred to date has ended up being summarized in verbal
screening comments provided to the planner (who, as you know, sends out the actual comments to the applicant)
after constructive discussions between myself and the assigned ODES engineer (Bruce Whittaker) and --in
regards to the tight-lining of the stream corridor and critical areas impacts (i.e. potential linear alterations) --a
verbal discussion with the Wetlands Biologist (Nick Gillen).
Much of this, and more, was provided in verbal testimony before the Examiner --in the case (Threadgill) where
Ms High successfully petitioned for Intervenor status. Much was provided in direct response to her questions, or,
in rebuttal.
If you wish, I can provide some mapping of the area (I have some copies of the Assessors 1 /4-section map
already printed, assuming previously that you would desire additional information), and can ask to find time on
your calendar for the (at least) four of us.
Kris
From: Norman, Paulette
Sent: Thu 2/28/2008 8:01 AM
To: Langley, Kristen; Nolan, Matthew
Cc: Kara, Falin
Subject: FW: Public Disclosure Request: ODES file Numbers L04P0034 and L06P001
Kris
You sent me quite a bit of background on this project which I haven't had time to review thoroughly. Would you
mind sending me and Matt abrief summary response to Ms. High's questions below?
Thanks
Paulette
From: Highlands Neighbors [mailto:highlands_neighbors@hotmail.com]
Sent: Thursday, February 28, 2008 6:46 AM
To: Warden, Stephanie; Norman, Paulette
06/03/2008
Page 1 of 10
Langley, Kristen
From: Langley, Kristen
Sent: Tuesday, March 04, 2008 5:37 PM
To: Nolan, Matthew
Cc: Kara, Fatin
Subject: RE: Public Disclosure Request: DOES file Numbers L04P0034 and L06P001
Correction:
Our testimony did include a response to the contention of the applicability of the intersection spacing issue. We offered a
professional opinion that the fact that 162nd Avenue Southeast was platted some considerable amount of time before the
two plats noted by the Intervenor, that it constituted the 'pre-existing condition' for THOSE subdivisions' reviews and
access locations. We had a ground-level series of photos taped together (to form a panorama view) to demonstrate
adequate sight lines at this location (no humps/sags that could obscure an on-coming vehicle), and, noted an professional
observation that MUTCD warrants for either multi-way "STOP" or signalization (requested by Ms. High) appeared to not
be appropriate given the observed volumes and anticipated use of the connecHon by these three pending development
proposals. But, that nothing in the proposed improvements precluded the installation of multi-way "STOP" if some future
decision (developer or County or City) was made that the installation was (under a theoretical achievement of warrants,
since I'm not predicting that it would meet warrants --and this email continues the public record that the Intervenor will be
requesting) needed, and, given the criteria for signalization, that, based upon 24-years of professional experience, it
doesn't appear that the volume warrants would likely ever be met --and even then, nothing was proposed in this
preliminary design that might preclude some theoretical and unlikely signalization.
Kristen Langley
Senior Engineer, Traffic impacts and Data Analysis Unit
KCDOT/ Traffic Engineering
206 263-6102 (Seattle)
206 296-7155 (DDES-Renton)
206 296-0176 {fax Seattle) 206 296-6613 (fax Renton)
Effective October 2007, my email address will be changing to kristen.langley@kingcounty.gov
From: Langley, Kristen
Sent: Tuesday, March 04, 2008 5:01 PM
To: Nolan, Matthew
Cc: Kara, Fatin
Subject: RE: Public Disclosure Request: DOES file Numbers L04P0034 and L06P001
I believe that we said that, based upon the firs] iteration of Barghausen's plans (which --as an off-site --clearly have to
have any Variances before engineering plan approval), that we concurred that a Variance would be needed on the sag
vertical curve length (if it doesn't change during site review) --but that supplemental illumination applied as a
corrective/compensating measure is common.
Our position that, as an off-site improvement, anything greater than 20-feet of paving is covered under the "extent of
improvements, for off-site" provisions in the KCRS. Notwithstanding that, even the sidewalk is --as a standard --not
"required" as an off-site.
A half-street on the frontage of a plat, yes, a sidewalk is part of the normal frontage improvement requirements. At this
point in lime, the other two plats --which have direct frontage on 162nd Avenue SE --are required to install curb, gutter
and sidewalk on their frontage, AND, as with Threadgill, will be expected to provide curb, gutter and sidewalk on the
common-off-site-to-all-three plats for the portion of 162nd Avenue SE that
was required for Threadgill as
(a1) a condition of SEPA
03/06/2008
(a2) a condition needed to provide adequate school walkways to Maywood Middle School, and
(b) will be required for Cavalla and Liberty Gardens as
(b1) potential SEPA conditions
{b2) in lieu of an, in our opinion, unapprovable Variance to a long dead-end roadway, and
(b3) a condition of approval needed to provide adequate school walkways to Maywood Middle School
Page 2 of 10
I would note that, across their frontage, and as explained in our testimony, Cavalla has to provide (under its current
proposal) at least 28-feet of paving across it's frontage because of a provision in 2.09.A.4 (re: alleys) that requires that
alleys connect to a public street (frontage, or internal) that provide at least 28-feet of paving. This, as currently 'out' in our
rescreening letter, includes a 16-foot paved section (centerline to curbline --consistent with the neighborhood collector
standard) on the plat side of centerline and a 12-foot paved roadway on the opposite side of the street.
Our testimony did include a response to the contention of the applicability of the intersection spacing issue. We offered a
professional opinion that the fact that 162nd Avenue Southeast was platted some considerable amount of lime before the
two plats noted by the Intervenor, that it constituted the 'pre-existing condition' for THOSE subdivisions' reviews and
access locations. We had a ground-level series of photos taped together (to form a panorama view) to demonstrate
adequate sight lines at this location (no humps/sags that could obscure an on-coming vehicle), and, noted an professional
observation that MUTCD warrants for either multi-way "STOP" or signalization (requested by Ms. High) appeared to be
appropriate given the observed volumes and anticipated use of the connection by these three pending development
proposals. But, that nothing in the proposed improvements precluded the installation of multi-way "STOP" if some future
decision (developer or County or City) was made that the installation was (under a theoretical achievement of warrants,
since I'm not predicting that it would meet warrants --and this email continues the public record that the Intervenor will be
requesting), and, given the criteria for signalization, that, based upon 24-years of professional experience, it doesn't
appear that the volume warrants would likely ever be met --and even then, nothing was proposed in this preliminary
design that might preclude some theoretical and unlikely signalization.
The Intervenor did express dissatisfaction with the use of the maximum grade in the KCRS. As a Neighborhood Collector,
the 20-foot section of 12% grade would need to either (a) be revised to 11% maximum or (b) make use of the "may be
exceeded for short distances" provision in Table 2 .03. Nothing was presented as to 'why' the use of maximum grade
authorized in the KCRS represented an unnecessary hazard.
Kristen Langley
Senior Engineer, Traffic Impacts and Data Analysis Unit
KCDOT/ Traffic Engineering
206 263-6102 (Seattle)
206 296-7155 (ODES -Renton)
206 296-0176 (fax Seattle) 206 296-6613 (fax Renton)
Effective October 2007, my email address will be changing to kristen.langley@kingcounty.gov
From: Nolan, Matthew
Sent: Tuesday, March 04, 2008 4: 18 PM
To: Langley, Kristen
Cc: Kara, Fatin
Subject: RE: Public Disclosure Request: DOES file Numbers L04P0034 and L06P001
Kris
I would like to draft a very simple response which basically says to Ms. High. No variances have been applied for on this
project and the HE report does not anticipate road standard variances are required. We anticipated the developer can
proceed with this project and meet the requirements of the King County Road standards.
Can we make these statements?
Thanks Matt
From: Langley, Kristen
Sent: Tuesday, March 04, 2008 3:26 PM
To: Nolan, Matthew; Tibbits, Chad; Sanders, Jim; Whittaker, Bruce; Kara, Fatin
Cc: Norman, Paulette
03/06/2008
:::..l,,,.o.A_ \ .
~ IA..l.
~c--,-::, L.
~"'~ Gs,
~UJJ. . '
4-IS<e
~-\.-
N<.c..i,c. c..
Bn.,,oe-t..u
K~t~ L
. ~" • ... ('C)::), ·• J, .. ~~ .. I").~ .l. .. -e::. . ..--k~,:::au \-t:::..
I . '-W' -= ._....(o,Q
. -~· \.."-:\_. ____ --·---... -. ·----,-• ··--. . ---·--.,
, __________ ,._____________ ... -. . --
.. d. c:.<-0. ~\.~ ,~ ~-. -9....,.·~-"-=~~vL~ ~-
-----------·-_,_ --., ___ < -----·· ···-·· -
.. . .. v,!;lo-.\ ~ • •:: ··CJ··· &""tt.~ .. ~ .... ~ ~ ~ ... -t\ '()~-~~~\'?.
---=;,1
I
Numb'
-~ er
I -
Location
--------..!...-
144th Ave SE From SE 141 Stto#
13430
140 Ave/Way SE -ITS From SE
Ch~nge the map view or apply fitter to alter these results. Clic;k a column header to sort.
GIP i -I--,
1 MP I Capa , Equestr
Corridor · Fundi i I . . I PAA , S city 1an
ng I
Need
! Priorit 1
· Priority source y
Misc
I . --I
I '
1 ! Urban -
I
j~u~~e_N N N
I
East
i
Renton· Mediuj
PAA I Nonmotorized m I
I .
Urban -I I
Pedestrian
Type
Pedestr
ian
Cost-
000
$0
Comments
See King County Capital
Improvement Program (CIP)
I document or website for detailed
: project description including scope.
j See King County Capital
Improvement Program (ClP)
document or website for detailed
192ndSttoSR-169 132-140AveSE
Funde
d N1 N N
Fairwoo 1
I
~AA; ITS High+ ___ ITS ITS $0 · project description including scope. _ ---------------•--
I
154th Pl SE From SE Jones Rd To
I
r Unfun i : Guardr
GR-19 I SE 142nd PL -i---156 Ave SE ___ j __ ded t,J
I i
N N
'Urban-i
Not in 1
primary
PAAs Safety High
I
urnan -· ·
·1 ail I $28 , Construct Guardrail
I
~
I Preliminary suggested scope -Add
Guardrail
HAL-
16 160th Ave SE & SE 128th St
---------
I : 156th Ave SE ITS From SE 128th St
_ -I ITS-191 ______ to SR 169 __________ _
1 I
I ! SE 128th St. ITS From 148th Ave
: ITS-28 I r---r
' '
I
_
1
1T_§_:34
NC-
SE to Mat \(~lley Road
164th Ave SE ITS From SE 128th
St. to SE May Valley Rd. ; -·-----t·
156th Ave SE From SE 142 Pl To
: Unfun:
' SE 128 St · d.::.rl " ---------
East
I
Renton
N PAA I --wroan--; · "'" ,. I N
!
East '
Unfun: Renton
I . I 156AveSE ded; N ! N N I PAA -,-T--T --,-
I left-turn lane 1n the WB/EB
High I HAL I Safety , $388 directions ~ --1----------1-Pr'ov1de Intelligent Transportation
I I I System improvements which could
Med1u I lmclude cameras pavement sensors
m ITS I ITS I $172 speed warning system I IProV1de lnten1genrnansportat1on
?~f~tt
ITS
SE 128 St
1 I i i Urban -
I
, . I East I
--~;~~n~N(_N j_ N •:~i"L_ITS_JLow ______ lT§
I I
i
I System improvements which could
:include cameras; vehicle detection;
!synchronize signals;
ITS I $3.819 .communications
Misc
Unfun I
ded N.(_N _____ _
Unfun
I I
! i
I i
N
East
Renton!
·uPAA I
rban -I
East I
Renton
ITS Low ITS
, Provide Intelligent Transportation
f System improvements which could
ITS _ :$1.328 ~nclude cameras; vehicle_ detection
Pedestr· I
5.40 SE 128 St 156 Ave SE . d~~---~ J_ __ N __ t-' N PAA I Nonmotorized_ 1
Orban~; ,
TBD Pedestrian ian $437 Provide Nonmotor_i_zed Facility
OP-
INT-52 156th Ave SE & SE 142nd PL
, OP-RDj SE 128th St From 168 Ave SE To E
· 21 I OF 169 Ave SE __ _
156 Ave SE
SE 128 St
i East ! I , I
Unfun I Renton' I
ded i N N N PAA 1--Operations_1 TBD :
Unfun
ded N N N
Urban-I 1
Not in I
primary:
PAAs Capacity Minor Hii!h
Op~ra~~n~
O_e_erational
--.-
Operati
anal Evaluate for turn Janes +---------+ $640
; Operati
anal
Improve Sight Distance--Tum
$1,071 !channels
)
I ! I 1u,uan-1 , I
' ! East i
I OP-RD 154th Pl SE/ SE 142 Pl From SE Unfun · Renton I I Operati I
___ ; -~? -~~~es Rd To 156 Ave SE 156 Ave SE ded N N N PAA_ · Cap~~~t~!_no~ ___ L_~w_
1
Operational I onal $2,435 JRealign Roadway--Widen Roadway
1
urnan-; !
. East , : ·1
SPP-: Unfun I Renton I , Pedestr
4017 168th Ave SE & SE 134 St Misc I ded . N, N N PAA : Nonmotorized Low Pedestrian I ian $27 'install crosswalk overhead light I ----, -1Ur6an -i I ---
I I East ~' f ~ 1 SPP-Unfun Renton Pedestr
4018 SE 144th St & 168 Ave SE M!~~-I ded N N N I PAA Nonmotorized Low : Pedestria~--_ 1an J $27 _1_lnstall crosswalk overhead light
II
!! I , ~lu~:S~-• ~' I
~ SPP-SE144thS1From168AveSEto Unfun, Renton 1Pedestr
r-----_ ~019 , 177 Ave ~~----___i__________ ~1~~--~ ded N1 N~ ____ N _ -U~~ _ Nonmotonz~ Pedestrian ' ran $26_2___. Con~~ct wal~y _ _ ________ _
: I I East I I •
; I Unfun
1
Renton , I I I
sw-s2I 156th Ave SE & SE 142nd PL i 156 Ave SE ded I N N N PAA Safety TBD Signal Warrants Safety $2,273 Traffic Signal
''":Ii{; ..
lo
i
i fi.'
~:,~.~~' :::.;~~ 'i ·,J. -·,.,,"
\
'\' ..... ' ,,,· .. ·'''' ·-... G:i . ~ .. ,. .. .. .... .. .. .. ..
-,..:e~~ J, -,, I"
l
-)!"
' ' !
(
,,
}
j
r~-
l' . /1
" + TNR 2008
Public Review Draft -Map 4'
l.,g King County
Legend
~J Bridge
* Capacity
0 HAL
Operational
t,. Signal Warrants
,~, Capacity
c:::c::cJ Guardrail
--ITS
• • Operational
Pedestrian
rn"---:"....,-Reconstruction
tlARS
lk
I\-
1
Cities
;t
I t
\ I
,f~---·J ,. ti' .
lf' ' ... . I -i~l f . .• :, "-
I) "
i I Jr-,
,-1.
Tholrtlormatlon,ocl..iO<lonlhls'flOp""1booe<o"" ... ~<J<li Co"""' ... ~""'" • V0<1o<y o1.,,.._ .......... Joe, to cNl,V.
<-<ltloU r.,lloo K,og Cour,:y """"° r,, rtP,,,Ml'lll!lono ot
................... ,"' .. """"''d·""''"""''"'·"""""''"' .. · i'flOU....M, o,l\jhto to""'""° ol woh irlform1tl(,n
'l,v :;.,,""Y ,.,.u 001 .. 11,1>~ ro,,..,g,norol. "'"''"'·
ho1too1,.oolclocl"·''''""""''"'"ld1ma~••IOC1udlno.b"'""'
!ml!odto,>0<tr4'onL!OtoO,,lpto11t,ro,l>'ll!'Ql"""lt,,,""' " "*""' ol 100 '""'""°'"'" com,i,,,o on u,.. ""'"
""vull orin1, "'"' orln!oo,no!lo, '""''" ""'' "orol>bllod
"c,p,,,,.w,in.,0~1rnlM~ho(~:",1C.:n'1ty
i
I
I
i
'
'i
'i
I :1
i!
i
02!1 05 I! .lMlse~
I I ,-1-3r1r~, . ,.--.
r~ :::W~ f--~sE-nsth-st ~
>->i,.,
sr;
1--· 1 I 11
.,: -
'-.
<O
~=1(·=-im;g-<O
r ' 't
y
-f--C
" I-
SE-136.th..SJ
~ ,-
~ -
f--~· I ,-
t= ~ err. A_,:::: I I LU
t= ( ,---Sj 3"J'. h-1/_ )
<I)
-/J IT l
a, ...
C-L( i
~
II\ '-I I
I -
,..
I I-r,{ T II I
1 I , l
I ~
'4
-cl
-Ut=PF
C: "' ,___
S£=1 h ~
_SIT~
I
I
~E-'14-yd-S,t I
LJJ ) -~ SET43raS~ ~ ..
a,
" ~~ }='.:) iii
~ .<! ... -<O "'
~E.1..4.4th..S.t ~ "'
t LU
I ""
LU '.'.I [ '1
....
Cll
0, ]~ 'ii! ' c"o, I~ -s co ~
"' .d!,s,~E._1..4.5.ff s ,.,. r--=::::: ... ~
LU <i,
~
~
N
~ ';!!. LU 1 LU "' ...
~ :i:!, ~ '.'.1
<.' "' cu
"(f-SE-1A6th..f>.c:) .. j ~
IT\ ~ ..
~
S~-
~t1rsr----.._ , I /; LSE._f..4.ZtlLSt . e Department of Community Legend Liberty Garden
& Economic Development c::J Liberty Garden
Alex Pietsch, Administrator [:.Jotyumts Vicinity Map
c:J Renton Parcels
February 24, 2009 "
EXHIBIT 2
0 150 300 600 $ ~~re,--· H ·,CH'. .c,.·.t~ ·,',1".!'1 t\' :T3::s· Feet
,. j; '[";? '';:'-,. __ , ':' C_1,:Y:"li _ '.:;J----;::;'::·-, '"<:i 1:6,000
~ :c
M
DJ
~
w
', ,' r-.. -'r --1-·"' --~t J ·-,
----1. '. ~i \ o\ % c/01
~1',:..~
ft 'J 1' V 1'.,-
' ' :1: ' ',
1;-t
'N i' -~
I !'c.
i '1 fr
-..___ I
1 i
' >
.,1:1,11 :
-! . 1! ' '
~-~-~~
,ii~
:1! ~-· '·"'-
~1
'
--j
'
1-0 ~
%
'bq_ \t ~
1
' >
J I . I 6 I ;e"f9 Ii·• 1 ' I 7 -, ••
. . -,, ~-E ~wt-~,~ ~ t ~ ~ 4 '. -5:-.... · ~ , I ,, I , . i, • I / r --·1' :-. . ' ' ' • ';'.' ·, . i'l.' ~' 7-K:-~'-.-J-U:Ab-D,L__. _ _c ' "-/. ~ l!l\1 ',,
. !~!':
~
1 @.\
' i, > -
I'' ---, !' I'
-\~ii' if ' 7 -!r1,;._ ·_ -1, i \ -·. -!i; .: >
.. F=-;~ +-' -,, :: ~
.
}_ ~ J1v--. t"-'~-t_'._: .... _ -1'"'_\~.: ··-~ 1,, . fu -. -~ -,,. --'>', I· ., r -: · ·-· ; · ~-,' -~ r,._,.. · l
. . *.:4,JE,-~~" . -__ :!:_ _,1::" ,", ' . \ '<g
.,,.-y_, . '--~·.. ~
~ \\{, ·:~
~ ' .
1 f;;;;·~~ (:~~ _' r ~ ~· I '~
_/; f;~ .. 0 ' ---" _i,, -• -I
/. (l )1t-. \--' . 1-ll' :I( ~
-----------c .... ____ . , rf A " " _ ,~ ~~ ~ 1 ,•.
, ·;st,;.,--~~ . ' I :0J ,, --J ~ ' ' ' , " !! " . !' C. --__ -1 • 1' 0 C " •s l , ' , o
'1' rt\ o E! 1 i" £; • -;.i ~ > ,, ,! I ' !( ' ' ' "I 3 -. ~ 9i .. ; , ~ _____ ,+__,,~-H /1.; --~)'-
,1 '\ ~. · \ l1~lr _ \\\
·. __ ,:>" ~ 1 ~ • ; 0 1··,y·.;,r;:,J·-,·-i," ,--,:-
---~ ·1 '~ \ ·~ '1--0
\ ! '.( jtf --::·· ' --~~~"_:_~"--
' · , 1· -i-, --1 '" · -
C ~ :, ' !> , ~
,,. ·""····-,a
! I p11 i 11 11 I l i l ! 1 I 1m Ii l 1i;i! ! ! 11 ! ! I ! i ' I ,q f;i ! I;: ! I !i 11 ' ,! _1 'g ~~ i j ! ~
~ ~ ~ • g n Q I~ i•:1 ~ 1~1111 j:.~ '!~ ;;1rm l!\1; i!! If;; s ~ ~ ~ ~ ~ ~
1
~ 1!1!'~ ~m i !='~ rl~ 'ii
1
~ :,18 11, .1~
; ! f ~! ~ ~ ~ 1i ·,'!i p 11,~ i~~i' :dl: 1!\~
i ~ ~ ~I I i i I~
11~ l !i! ;! l l! i ~ '!: I§
,~ iljli '! 'i 1 li I ,1,<'i •Id I . I i 'i( • _____ ___. ;, )I
!
-·· ... !
11m11 i
""iili i ~
"i ! ~
; i m
l~l!
P.
!
,, ' ,, _[__]
(\
~ a I ! · i 11 ~ i { ~ ! -\ilfl
1:'· Jr:,,,\
~ ~ t, -' "'~ '"s:. ~ ',. -.9,
• I -
j ' ! I l j I li~ ~
111! m1 i'! !!! !I!/ !I!! lji 1 mi i!m l I)) ',l
j•!j !1•11 •11! ;i i,;! ;,:! ii'il I'!! I ~~ (\ 11! -1: ! 1: , :! , ;! ,1 ,1, , ~v
~ /;la ~ , """ .., ""' """"""' "'' : ~ 1 . )fl ..cG .s ("'11 """"" ... '!."'"" ""'9
_, __ !fll" "I" " ~'!_ """"'"t'I"""~ OOIMlITT
no.
~
~
~ ~t
00 t:d
~; ~ ~
0 ~ ~ r ~ ~ -, . ~ ~ ~ ~ i
i ·_ !:')~ ~ ~ d ! a~ C
4 ~ t::, :; ~ ~ l:tJ
~~ ~
~
m • C
a,H.-,<,
I ,.~. I ~~~-; 102 5 12NO ~\IE.NI,),( SOl/TH 1--
~(Nt II~ 9S0Jl ,-... ""
1~25)2~1-0222 .,.
li25,:!~1-a1~1 r...-.: "'--:, 1
Iv DAVID M. PETRIE
811 S 273RD CT
DES MOINES, WA 98198
PAEUMINAAY Pl.AT MAP
OF
UBERTY GARDENS I I ' " ' 0,.,, ••• 1---~~"~~ ,,--<oo
~-
~
' ' i
f
' ' i r
z
.,.i
' '
, .. ·/
-~. 8 '.,,4",,_.J
• I ' ' 6 ' .,~~JO";
: 3 -
b ,' .,.,., ~·-· 'j i .
~" , ,,, ;.;.
, ,.:; e,. _.1,,.,;;(, . .1
' /7.; -
u
--
'
1
:~m:=~ --un .. u
I
I
.0.::.:
/' &VJ .,.-A
~~
PRELIMINARY PLAT MAP
OF
LIBERTY GARDENS
A PORTIOO OF THE SE 1/4 OF SECTION 6 TOWNSHIP 22 N. RANCiE 5 E, W.M.
KING COI.JTffi, WASHJNGION
·' .
EXHIBIT 3
)
C
,L
'
t-z
r -50'
~5=~~
::/::;)·~-
d.0~"'
t\£0
0 r 1P\.;,.. 'f~-""
'>t.:· I ).' 2~". q -~ --··--;,(<; " (-"!3"' q.•,t .
f'_A
(_~
,d<
s<c9 I'''. : <Po'
"'.,pl'o e,l'---11-v '<-•'--oif
,<"\(~
cP'r-·
{,-r.,
,.;.
L---T ..:.~ rr J
-1-.'.+i·--· -·-. ---
1 : f , !,---:--t -l
J
&gv
• ..
----
ffiEL J!,AIN AAY PL/,T MAP
OF
LIBERTY GARDENS
A PCRTION OF lHE SE 1/4 or SECTION 6 T()l',NSl-l!P 22 N. RANGE 5 E, WM
~NG COU'ITY. WAS/ I NGTON
i pl'»'-1
: sEflt tJ~ ,:r.;t:.:~~:)
,. I " /• MAPLE ~'?OD
•... ,,;;. ~~
0 -" &-~
.. ...-.. ~ ,•'
,,.. ~1t.C
v:1P~
f"'.'-f .-,·
c.: ~:~c·~~---=~· ... _--·"'.'-::,::)~. ---·-·:f :: ·::
m ~, i .~.,
""",,, -...... ,,
,1(,,
' I --} ...
M .
~
, .. ?:r:' I < -~-·~
. ), ..
/
~~~
1..-1:-. ... ~
~§§!Y /~.-A
I ~--
't~ .,...,.
~\·
• ~,.
~·:~v·' WPICf-.A '
).l:.:)o..t.i
"1:~li'!(j,
~!!l(Or\~I 1.t:••••
" ~~ <~:.}t ·-~-,_· -~~-~~ --j
~ . u
.. !t.
1 ·o' ,
o ' ,.oo' \-,oP. I
,,,.
~c .:~~6 0 :
e 1'0' _______l_
~..,
!"-A
-~-·1 -
~/
.-,,.,n,1/-t-l"" _ _..)JU·•'-•
'~-· >-~ &~-'
d
, ~r --
_:r __ ,,
""'· "'---~'~'._-,':
i _:.,:.-----
f '."f:..:. · .. ,o <:l~t-? l~::z..· \_::/1\
' -..JO\.·. \ ! ,, ·,
I
f' ___ .A ,:£'?
EXHIBIT 3
!a!;GAL QESC!}PTION
r,v,c•s ~ "M.• t 81.0C, • (((l,tJ' .,..,.. '"'( o.c1•1. ''"-"C r\ .CCOl"':)o<
re, I\'( "V.1 f'l<"'(L"" "l_('tllq)(_O N "'(\{L~ ,, (Jr "V~ ~"'..( ,, ,,. o:w:: ro.,..n_ .,..._..., .... ;.,.,..
VERTICAL DA TUM, W l ,N --
"'fJlr:rr-Y ~ ~· ~ ~
VlC1Nm' t.4AP
I .
I Ii
d I' ! ! l i !
ae [, ·,~,!H iHH
~.1.1,1.
l.:1'1 '7., ~ i
~S/~j ~j>, ~~.~ •
~ ~ ,_ w
~ ~
>--IL (3 ;o~
::::J (I) Ii! ::::J
IL
BENCHMAf11(,
~tr,:,:_t(~~"'lt't:.,~CTIOO< ~~,~·~ -,_X( ~ I~!>< a.Y[. ~.L u:1 ~1:1:1,1 §
MERDIAN
~~!rr.ill.ej'T'Y\\Jll',(Y~
BASIS OF BEARINGS
J"( s UL or"" Y 1/,. t;(t. 1•-h :,,i...~ "ll
---)1'.:'I .....
ENGINEER/PLANNER
9,t,l""..Hot(/5:0ol'.Xlro".;U.T.-;;~.N;.. !:i5 :J."'":n .-.olffl<
~~n{.~; !lf .. ur.
(.fllff,O· ...,'!AJll./""'""1.P":l'llt1!
OWNER/~VEl.Of'ER
~"'fll!lljQ,¥,OOW"°""(
~H ~l~'"Cl
ci.5 ltll'JIIHD, M M IN
(l"5')1•~il'i,,
lNDEX TO SHEETS,
C1 OF 5 PRB....MNARY Pl.AT MAP
~~~~~Oril PJ
~-~ C•~I 1n -MOO
~Sl'.V<IOO\"'I' •=1~......,_...,o(
"""-"'<-¥
{eoct n 1-01,
f'\.Oflk.>.JICIUUl'CY
·~ '""'" a.o,11.(" ""'E all ~ ......
(!!00) "1•··~21
~•00<""1JIV("'L a :ur.u . .,,, 'l!lln}
:::~~-
~J~~~l"J~ '""""~-(0~) ~M ,,s.1
C2 OF 5 ~ FOAi) NO on,.A,fU,,QE Pl.AN
C3 OF 5 ~ ROAD P'ROA.....ES
~:~·'',, ~~...__,,
(4~l -.J1-JOOC
C-4 OF S ~ OOAD ~ PLAN ""° l"ROFLE
C5 OF 5 ADvACENT POOf'e!T'r °"'61$ w./'
PL I OF 2 PfEl....t.e,(Af PAA<. NO l...AIOSCAPE n.....AN
PL, OF 2 9ICW'-FICAHf 11£:E fl:TEHTlON P\....AN
NOTES
"6~(550 1 .. ~ "¥!CU ~.....iot li.,:O,C,-0 ,..,. G•,O
,;II\""°"°"-1t:r"<--..r ';( • S( ,.., ... "I.
'A<""-'I V!t ""'IAtr.."""0 (!4111,_,,.,
1 -:"'9SCD ~l6-l.Ol l9<llf-1'W"Zif'l'C{
~r.qZ,.-~-·
l ~ro,...;-,-· r.,~~.~~\
, "'(~-...w urr -~,ttt
~(~~Attl>tl·
~~~~'"1
,,. ~LC'f ~t.'1'01Q.n
\
0.£,'-~~ • ..c . ~~" ;v::>4
<-"'i~~
«:!('-~,,*.
~\; ,...~-.,J ... .., '?-J..
TRACT TABLE
U5( I 41Uo·11;i
--I"·'"' STQl!lll ~fll(CffA-!'0.1 •(1
.otffV'l(Dflll,,o{"IIIIT I.fl!
IC/H!U'jl__... 1.'J7l
~[ 1.01';1 -· .,.
n,,t,,1,.l'M:;'l ~IJP.•,..1,t.1,1').IIC;
ft;'t.OI.. V)'I #fU. nuo4 \.f. \.ID lit;
TC'l,lll.v:(-:.,. *·"''-' t.n.tC;.
'"""'""-
"' ~ ~ ti~ f
0 ~ ~ a.. a: .. Q
-<? en 't ~ ~ ~;
§1cog~
~ 13· ~ o en w
0
~
h h
I I • I t I ,I
l l i l
~ ~; t ~ B
~ 1i
i:: ~~
.f:' .. i
::!... 6 tl'
~~~~~ . '''•.,
~ -~ -.$
~ '
.... ., "; t;.,,. ....... -
<t
~
~
z
I 1··· ..
I
~
~
l
!
I
' !
I
··'
·"'
·""
' \
L
,.•
( . ,-·:.s -
1
~ ,""'~' •.•
\
\ 100·
3 '
b ,: r l'P')O .,,.-j . -J , . .. / l,· i '.
PREUMINARY PL.AT MAP
OF
LIBERTY GARDENS
A PORTION OF Tl-JE SE 1/4 OF SB:TION 6 TOWNSHIP 22 N, RANGE 5 E , W.M.
\34
~.·~ tl,.t
\ ,;--
35---·· . . .. -·f., .-·,,-'
,.iH,•• ........ r-.. .,t,,,),e,f"'
i
,w, "' ',
~
I
( ( I ,
KING COI.Jtffi'. WASH1NGTON
-~ .•
EXHIBIT 3
SN3CJIJ'ro A.l.tl38n
~O:l NV1d ONIJ.N¥lci 3d\'OSON\fl
N31'13::>lfld3!J 331:U .I.N'l'::>i::llNOtS ON\'
NOU V3tl::>3l:J/3'JVNrvl:KJ l"il:!O!S AWNly<jn3tld
'°1ll1
1 -~ ~l •-o l · ...
1
Jr .fl
~~~] J•!
"& ~t ! t ,-d ~~-
I ~;) {•
,,. ·n .. i t:~i 9-~
·i ~ f t•!, i !e ~ ~-, -l•i !fi; f, 'h H mu r11tij r ~ ••
<
&99-91>'6 (£SZ)
86186 VM "S3NIOl'I 630
l::>Ol:!Ca SU$
31lil3d ·y'j mwa
• I
h !·· H ·U ., I •-
i! ~,,
-[,.
!iP . scr, ii gjf '"? I
•i ~,,i tf ;;f If ii ~H ff!f i :hi
I
!Il < ....
()
< : . go .J
I ii r
< ~ s < :
(I) ...
~
I=
•I ' r, r d ' ·~ > Id·
gi' g~
~; ~l
!l if
~;,•1-C\)Jl,l,dJS 1"i'fl....0.~J~,V,
~<,tr:,,,rd))l,ll')l,)'"W;
<
i
t
'tlfJ lt!S· 1~li~!•I
lU'il-l,;ZC~l t l
zro,ae T"-·1~l•
Hl/'IOS ~fl ~}S'r {)t.U 'llit
fr-z
r • 50· FJ::E:t_._ ~)v
~ ,c\
PAELIMNARY CRADNO APO STOAM DRANACE PLAN
OF
LIBERTY GARDENS
,\ POfl110N or THE SE 1/4 OF SECllON 6 TOWNSHP 22 N, RAN<X: 5 E. W.M
KNC COl..tl'rr, WASH.'ICTON
M ~1='1.k. ~oo'l> .-~
f-< ·' ·,· /'.
~ ·. •• ,t '1 ,r<=r --J . . 1"' 0 ; ; ,· --· ~ -:;...:t"~ ..
. ---· ·::..,,,,;;.., --··--~ . /S:=fm"~w~--.. , . , . . ... --~-.. __ .sd--;-----,, . .. . oor-wdi ----::::::::;;;;;£ ... ~t:, ~' .. ·1 --I •
.-' ........ ::~.·:~l:-__ ..... ......... . ,
e •
i I '
I t!i; i11 . ~,8 ~ t q ~~!I
~~~u hrlu
oz ~ ~ ~
;,;; w ~ 0 O a ;!, <l. <I ~ Z IL C
)-~ 0 ~ ~ 0 LL
. ,. r . j .J1! .. JI!> .
~~ 5 ~~
Q.. ~·· •:':, I
.,
t
c(
j
1 ~ v
....
-~
'f"•·, • j 'I
: '' 1/T~
~ ·o,•t
~~~/·~·
' I IIV..•• '
·"---....
EXHIBIT 5
i
r
~:2~
.-
".; -#
,1.,•'t p -·,\" .. ,
-~~~· ,·•:,·,
I( 10·0·
1---. ~, ··-~~ l ,o-o
• ---·'
.._')Ot_ "",A"w(N' .. ,~ fll =..e.t;..~ ~,1~J".
~· ..
-.. ~,.. ' J4 ----'-1..·•·-~ ,, .•
I __,_,, ... --.\. I ,. -..... I ...
~..,.r •. 1 ,;,<,n . o ___ I
-'~-$1 ' IIH~·•[ 11 ,.....Ji...~fi fr·~ .;:Ji!
, ,...-.,, '°""-K'l i «-o.-; .. 1r,•, ,1?,l=11 , •' --1n-:1.1 ~i ,X,:-
...,._.1, ~• wt '--,oq ,-001-// /',,. / i.-..o,;: M.Ol"I. ooi ""~
1 CCW,f '.:!£00fF',.(IJl"..'.ii!!l1 -•. /,/
'l """""'~"C'I( ;~~.~"~;}""·' / ~~O~TION
!
! ~ 0 :~
Q.. ~ lt_ I
:it g (/);
"'~~ 0 (/) g 2 ~ &; ~ 0 (/)
~
h h
, ; • I , I .1 ~I l 1 l I =1
f.c
:;!
L ~
!i ~~ ~ I I .... ; ;; ;.;
~~i~
g f§ ~-!~
-~ l !
Ii
t~
.,,~"''"''··-. i -~-1
'J; ' 0 ,· .s-.,.8 ~ ,o•"'.r
~ "'
'!f.~()("'('~OO'I~ • N NII ..., ................ -· .. .,, ~· •• v ~, 1 · ..,,. 1·
(C,,,,V IV'fSVJ'"L( .-c: "' -u
EXHIBIT 6
Legend
CJaty L,mts
CJ L iberty Garden
Ren ton Parcels
I le r-.:ame H ,C ErnG1S_~r0Jec:s·v1c1r1ty_maps•
x:Js'.pa·ce s_ 14570014~&0' :,:) hberty_·sarjer _oer ol rnx:::
Liberty Garden
Aerial
February 24 , 2009
N
150 300 600 ----===::::i Feet
0 $
1:6 ,000
Liberty Gardens Appeal Timeline
Location: Southeast of 162nd Ave SE and SE 140'h St
Applicant/Contact: Dave Petrie/Hans Korve
File No. LUA-Proposal: LUA08-093, PP, ECF (KC DDES File No. L04P0034)
Timeline
December 29, 2004
January 26, 20~
May 11, 2005
July I 0, 2006
October 9, 2006
August 8, 2007
May 2, 2008
June 20, 2008
July 7, 2008
August 11, 2008
October 6, 2008
October 27, 2008
November 10, 2008
December 15, 2008
January 5, 2009
EXHIBIT 9
Application submitted to King County for Preliminary Plat and
Environmental Review for a 38 lot plat
Application deemed complete; comment period commences
Road vacation request is made by the applicant to vacate both
162nd and 164'h Ave SE on the frontages of the site
Vacation request denied by King County Road Services Division;
no appeals filed
A 2nd road vacation request was made to vacate portions of 164111
Ave SE along the frontage of the site
Vacation request denied by King County Road Services Division;
appeal filed by the applicant to the KC HEX where decision to
deny was affirmed. Applicant appeals to the KC Council; where
decision to deny was again affirmed.
Applicant submits revised proposal to reflect denial of the road
vacation; 36 lot plat
KC DDES Environmental Review threshold determination issued;
DNS
Appeal period of Environmental Determination ends; one appeal
filed, by CARE
Property annexed into the City of Renton; Liberty Annexation
(Ordinance #5398)
City's Environmental Review Committee (ERC) adopts KC
DDEES threshold determination and starts a new appeal period in
order to assume lead agency status and hold one public hearing for
the plat and the appeal filed
Appeal period of the adoption of the Environmental Determination
ends; a 2nd appeal is filed by neighboring property owners
The City rescinds the adoption of the Environmental
Determinations from the KC DDES; previous appeals negated
The City issues a new Environmental threshold Determination
(DNS-M) including 6 mitigation measures
Appeal period of the City's new Environmental Determination
ends; an appeal is filed by the applicant
March 17, 2009 Appeal/Preliminary Plat hearing before the Hearing Examiner to
consider the preliminary plat and the applicant's appeal of the M-
DNS
+-I'· 50"
~ r
vt-i'i>\...,,._,.,-'i-o
SfC ll, T-/J,1,1, 11:-:>.: ... ,,.
'iol:C 7;°.T~;-... -
OIOr,trl)YN;;AT'EO)
(!i§J})
f',-A
f',-A
ar5;.--rv
,,_o'i: l".d'Q:*-.,..;:fa'?#
.()~~
,...Pv--
i //~
/ . I ;~•-
. :--1 I -: -~.
I'~--,
/
/
/
t--6?9
PRELIMINARY PLAT M AP
OF
LIBERTY GARDENS
A PORTION OF TIE SE 1/4 OF SECTION 6 TOWNSHP 22 N. RANGE 5 E, WM
KNG COUNTY. WASHINGTON
/ N"' '-''"'"'<~.,!,_ ,J.
/
' s~"'-' "°' ,:;~ •• ,o t,
;,
J
1
~~I.J"!"'1li'OI.IU.~¥0
Lllf ..... ~ftl~l'(•IM <:-~~
~ .. ~!:1.'~~.~~ --1
LEGAL DESCRIPllON
'IICNTY MAP
f',-A :· : {>J, ,.,~/ -
,..,u-':-1:_.~ --~ .,
)~~ n:to,CT",)""'1)~ . .-..:ic."lt •U.tw'l'-1"1..ic.:·rWrCT\.~
I {-·-~
·')" , . 4 WPS:,j'"ef,s'""""y _____ c:>-...C-,c--. ---r --· I /-:-~2:::;,.:'JF;\"~ ~[ ,.Jf ., ,I-s> f_ }' a• > t r.l • . rr ;,,g' -~ i M ; ;;p a '". ~ , , . 1 .,,./ ,. ~
'----. /_.• I '"51"••C
!:"()~11,"-,<fH"',
O("(\.O"',l(Nl '(;Q!I"-~
--.........~ rc·n-rf _.,,,~
I'
&.'U~/ / f\_A
... ~!H J <609
,,;~L>' ('
I \_o 1 }
,.o... .. oe•oo'
s P '\
1"-C •l\,e.O :
0 10 '' ____ __J_ __ _
£-V
f','A
c§{i-P
0 ~~.71 \ . o:.:)1 ~ C
'7'/.. ~I .._f_ ,"f '
,_:l:l,G ~>",Bl,·,
i "?> ·-"'
: "' \ f',-"
\
'-. __ \_ __ "'-. I
y '.I ---/ I
::.:;~~~ .. ""A.Al(l~r:,rv.r:,,<'l(,(t l
VERTICAL DATVM• -·-/>Clltr<O'~~CO'IT-u....-
8ENCl-t,4Afl(, r.ir,;1: ~Ill~~~ .. ~,:' "''~~10.
MEflDIAN•
~<£¥ici>.Jl.rv ~ t.e»ITM.
BASlS OF BEARNGS
~u,.~,r::_,...;,vt1•.st.t ,,r-i, .. ~ ....
8'Kllf>EER/PLAl'ff:A
~ .. C3CSl..lfNC~llt!,.N:
!f.~~:1"':usw-..
i~t.r!i ":l,Z!.,,., ~··c· "I.I '>lJ>I./ ... , .... ,,mt..~
OWNERJQ!;VELOPER
~l~~~..,O W O\f\fll
en;...:~-•••
(r..))-·Mi•1
UTIUTES/SEFMCES
NOTES
l;~.?1"~
(•~J ut.i-lM.;I
~"'t.~IIIIIUIICIS".tiC ,.,..,.v,ni,.s, ,.,..,(la _~
(•n ) Z:.)·MOII
O\,l(,{"'SCO.,,O ~•
1:i:a ':.61~ A\'IJOUI. .._
l'llllNur .....
(eo:i) n•-•~•
"V(,[""''.O.O'<J~• •;i.·~·~~ ...
1'1(\.1,~ ...
(-)!l'''l '
~ ~hlo(;CQM.._-"'( .... fit <'\.M<OC",Q.l'V,
""""""""-1>':u,.;t••lOJ/i.:,
9 llfcl,;IA(0 1o'N-LO·Oll(on1.JUr[L
10 ... :irovri ............. <'ll-.(1 ... ,,\fffl
11 -...,.; '.,lTl!,IC~~/l-l,C,,-1 I Jt, '1.1"0'<'5.
?i~~~~u~\ rm
tl OW{-,( ,or ""(.l. >JJ!~ '.,(t n
I ) ~~~-1;)/>Q(".-.., D*i.£"-....___,..-, •• ot,.J.IL ...._. ()I.Ll"'ll' ~ '°"'
...,.._:,,
•!ICt'(·l'lol~ ..... .._
~ .. ,eoo,
Uroillr .O'.llolCAS.I
"'~ OU.,,.J>ti -·• -~-
• . ...:.COOJ•'·•l'IIIJl'>'""'"'W'..lr..
ll'tlJl:.4,'l<""l~'Sl
111.J,JOOl •lri~
(•Hl~}I}'
~.~.:;
cs.~ ... M.:11
(•<)) IJ)l-,WO
BUI
!~
-. I I_ :I
i • ; ! ~ ; ins 1 :::, (I) z ';;: w
~.s s 1, 0
~ sn g ~ u. ~ ~I ~.~ H
i1 nH i O ~
l:'.1~ ~ It~ k_l 5 !l! .... ;:;n ~ -'
~.:.i ~ ':I '' l
0..
~ ~ ~ ~ i §,
~::;?~~i !
•• _ •.. ~ 1, I
0
.-t
t-
i-I cc
1-1 :c
X w
"' ~
~ t-~ SZ?. ~ 0 ,c( u,
0 ,: lfl ~ ~ af ~ ::::; ,..... w O>
"'z~ ~ (I) 0 f;l
.q;: i:: '.:?; N
0 "'(/)-w
0
~
i!As~~:~~-·-... ~ ., t · ~---\\~. ~f}l}
~·1 ,;pf/
~~ ...
I! .
} t
, I ' ,[ ,I
1,; p
i • ! ' j
~¥ .. ;• <,
! ~~
~ ~ ~i
t t !i e& ;r
~"' 1·::i,,,,,~ ...
.:i"'~'>,1.\
<>'.~~ "-! :t :
"'Q,' ' .. ,..:.:-·
ti-9 ,,c;o,.
;:!; -I .,
!::!
• ? ,
Windows Live Hotmail Print Message
Liberty Gardens, intersection stuff
From: zigsterdog (zigsterdog@comcast.net)
Sent: Wed 3/11/09 10:33 PM
To: Highlands Neighbors (highlands_neighbors@hotmail.com)
Page I of l
Attachments: t•~
2nusel2088.JPG (795.8 KBJ, ATT00001 (U.1 KB), 2ndset2092JPG (776.2 KB), ATTOD003 (0
KB), 2naset2089 JPG (5414 KB)
Hi Gwen,
I 1 ve taken some photos of the inteYsection of 161st and 144th. For
some reason, when it's snowy or the least bit icy, this intersection
is incredibly slippery for cars heading north on 161st to the stop
sign. Even though it's just the barest of Oeclines, it can get so
slippery that cars can't stop and end up sliding out onto 144th.
Even in my Subaru, I 1 ve found myself sliding with brakes locked out
into the intersection. I wish I'd taken photos of the guy 1 s mailbox
on the corner when it was crushed by a car that slid into the ditch.
it was just this past December. He I'-ad the most pathetic hand-made
sign leaning against his crushed mailbox that pleaded with drivers to
slow down because 11 he loves his fence 11 • I guess he was thinking that
the fence would be the next thing to go. Anyway, he 1 s put his
mailbox on a six inch post of pvc pipe now, and I did take pictures
of that. So for me, there are two major reasons why the 162nd
extension is a bad idea:
First, monkeying with that watershed and trying to control and
enclose all the downhill flow on that hill is asking for trouble.
Those of us who are downhill will end up paying the price if their
engineering doesn't work perfectly according to their p2.an.
Second, adding another intersection so close to the two existing ones
is obviously unsafe. If cars are sliding out of control on 161st on
just the slightest of slopes, I can only imagine how bad it would be
at the bottom of 162nd on a steep hill.
Regards, 3i::..l
FACING NORTH ON l6lST -IT'S SUCH A SUBTLE SLOPE THAT YOU CAN'T
REALLY TELL FROM THE PICTURE
EXHIBIT 11
http://sn 104w.sntl 04.maiL live.com/mail/PrintShelLaspx?type=message&cpids=34 ! 3cc2c-... 3/16/2009
• • <
2nd set2092.JPG
~.., Department of Community
~~~ & Economic Deve _lopment "M<:: Alex Pietsch, Adm1n1 st rato r
Data/GIS Analysis Serv ices
Ad riana A. Johnson , Patr ick Rod ui n
EXHIBIT 13
r _____ j ________ _
-----
Roads Classification
t7.J City Limits -P Primary Ar~n::::tl
Classification -M Minor AY--k--r-;"' 1
F Freeway
-CCollector
L Local
Fil~ r~:im7 -I 'CEJPJan119 \G IS\GIS_cr :JJe::.::s'.anrc-1:a:1o r s\'J irv1oocl a·Y1.?,\\
O"'\)"CS'to:oc_c ass:f ;:;at o·· ···.:d
"
Liberty Gardens Appeal Timeline
Location: Southeast of 162"d Ave SE and SE 140'h St
Applicant/Contact: Dave Petrieillans Korve
File No. LUA-Proposal: LUA08-093, PP, ECF (KC DDES File No. L04P0034)
Timeline
December 29, 2004
January 26, 2006
May 11, 2005
July 10, 2006
October 9, 2006
August 8, 2007
May 2, 2008
June 20, 2008
July 7, 2008
August 11, 2008
October 6, 2008
October 27, 2008
November 10, 2008
December 15, 2008
January 5, 2009
EXHIBIT A
(PP Ex. No 10)
Application submitted to King County for Preliminary Plat and
Environmental Review for a 38 lot plat
Application deemed complete; comment period commences
Road vacation request is made by the applicant to vacate both
162nd and 1641h Ave SE on the frontages of the site
Vacation request denied by King County Road Services Division;
no appeals filed
A 2nd road vacation request was made to vacate portions of 164'h
Ave SE along the frontage of the site
Vacation request denied by King County Road Services Division;
appeal filed by the applicant to the KC HEX where decision to
deny was affirmed. Applicant appeals to the KC Council; where
decision to deny was again affirmed.
Applicant submits revised proposal to reflect denial of the road
vacation; 36 lot plat
KC DDES Environmental Review threshold determination issued;
DNS
Appeal period of Environmental Determination ends; one appeal
filed, by CARE
Property annexed into the City of Renton; Liberty Annexation
(Ordinance #5398)
City's Environmental Review Committee (ERC) adopts KC
DDEES threshold determination and starts a new appeal period in
order to assume lead agency status and hold one public hearing for
the plat and the appeal filed
Appeal period of the adoption of the Environmental Determination
ends; a 2nd appeal is filed by neighboring property owners
The City rescinds the adoption of the Environmental
Determinations from the KC DDES; previous appeals negated
The City issues a new Environmental threshold Determination
(DNS-M) including 6 mitigation measures
Appeal period of the City's new Environmental Determination
0 '1.ds; an appeal is filed by the applicant
.t
March 17, 2009 Appeal/Preliminary Plat hearing before the Hearing Examiner to
consider the preliminary plat and the applicant's appeal of the M-
DNS
~ r---------1 <:,j~------ri
Sf=143r"cFSt
_ . D epartment o f Comm unity
<-~· & Economic D evelo p ment
·,.~ _ Al _ex Pie tsch :Administ rato r
EXHIBIT B
(PP Ex. No 2)
~
~
Legend
c:::J Liberty Garden
(:.J O ty Limits
c::J Renton Parcels
.E_1.4.7.th....st
Fi'e N am~-t,-·'CFD\G 1S_prOJEC15 v (:i'l:v_·~·~~s
rxds\pa;Gc>!~_ · 45,oc· 45&G" ~J 'cie t·, ~a·de·1 :-nxj
t.u
CJ)
(l) ::.
1-..c: ~--~
IJ:lr---~
~
Liberty Garden
Vicinity Map
Feb ru ary 24 , 2009
0 150 300 600 -.. ===----Feet 1 6,000
N
$
,-.,. m
iJ >< iJ J: m
X ....
z DJ .... 0 -I
w
"-" n
St i-1 -·
--· -·-· .• ~ i ~ .
I I
124 2 4
~. ·,I ' ..
\el I
I
i :,
i 'j l
.. -I
))
' I>
•. ·, ~~
I
1:.-.:...
I . i:» I
mi , ,Aj r · !j !
))
,\
l>
+ ~ ~
'' T
I
"· s
V
~.
';
~a,. lg :'-' '·' ,-....---,~ .... ·. _ _, ~:.
"' fr. )' ,.,, . •,
I> ~
~
i ~3i ti~ i;~ i~~s :J·~ ,1~ 7~}1 M ii :1 ~ 'llj ~t ~ ., ;f :;
DA VlO M. PETRIE
8TI S 273RD CT
11!s
'E l,
c < 1&
' ;}
,,
;; I
~ !s
!Ji~ ~m ~!(/! ,,~i .. ,,~ I~
!J?~ ~!,' 1(/!
~ ) //)'ti .,.:,g ~ Dl'I l ·~ ljl/.)1 ~ ..s ::-,
I 11 1; l,Q, Al >ti
1::.
.'\'GU,ul oO&:CCI ~..:,.-
~"CIIUCC, a,,...o,n
PREUMINAAY PLAT MAP
OF
+.z
r -so·
~
PREUM'NARY CRACINO ANO STORM DR.u-J ACt "u\N
or-
LIBERTY GARDENS
A POffTlON Of"' 1 Hfc SE t/ 4 CF st{':110 1'1 6 TOWN SH~ 22 N. R,\NGF 5 E. WM
r lNC CO\JN1'Y WASl RNCT()N
,.._...,
,:-':\ " .,
r • -=" ""r _ .... ..... . ,' ,,; ,.,, ,,' . ·.-:: ~t ,, .
,,-j .,a,•,C ··-~'"· ",cck ec c'HF.4,'!fr'Jif,ije,!':,s~'-' .,--, ,,; t -~' !?~
, ... r ,._f. 9 )?. .. 18.
20
-~~ ~
,=:.;.~:~
2z ~~ ~~ ~~t
>-~ ~ 0
z ~ ~o ~ l-a: Cf)
a..
s l '''" ~--~~ L . .21
... ,~, .. i -1 -1.;• §
\ '.
'J ~-..,?,,I
\
3:r, I , :i2 · i,•, ,\• \"! , ..
34 ,.,,.,,
.,)<.
...... ,,
'I---' ~ ---+1 .!l
22
~ .. , .
.i.:.
r-:
-~
!"l.f'l t ~;-t"'-""C; ~~.1 :-:-•-'0
'
.~,;
-----~--
. _L_ ~····-· -·--,
,--''·'-I I
... ....,.n.o.-·~v.,.,, .. , ~·· lK
•to,,,.ll(Oot•f--.~\C.O.
c o,,,,r,-,1';"'-)\1 (3,lC •111
TYPICAL
ACCESS TRAC T SECT10N
%:l 1 • eJ f.:;4---
,ll'llllJl"t'V-»(l'TVT[ac,,,a J 1 . ,·. ,>I
f'
EXHIBIT D
(PP Ex . No 5 )
~·.,~r ~-=ff•:~~ I'"' 7. ~~ L ----·-----
1..~;-....... I
.. -----
i(.-: 1;~1;--'··-~_.,_,._
,.,.,.. ..... ~ ) ----· .. ·-. -.,.,... ' . .. ''"' "' :~-·'" ~:""'..:.... . --•·M>-/ -• -~=~1 r -\ '-""'"-"''' .•. ··-/--;~ ·""':::.::'!!:""·';,, ;;;;El
, _, 'Vo'"IIIC1'0L'l"''"' •.s·-· -...-,~a,.,v
<O(),',.... ..... :;o:v.1M'"l ... ,IF!
.. ~,0(~00-'lt'..
:.~~X.t'Q"(•C:
,. / .... ,.. -:
' /
T'l'f'lCAL ON-Sl[E
PVSUC ROAD SECTION
m w I-O> ~ (.) <(
0.. ~ 3:_
~ R fil
"'Z
~Cf)~ ~ Ji; Cf)
~
I ~ f ' !-: .
'I 'I • I RI !
l I j l '
i
.,
~~ t
~ 2 !1 ~~E ~j
c,,.a .. &!
~ ;;~ I -·~.;;· i! ~~~ l ~
::)"'~~ ... ,., ... ,
< , X . .
~ .
as-~ -•• /
9 •<-"
~ ;
_ . Department of Community
~. & Economic Development
~~; A lex Pietsc h , Administrator
EXHIBIT E
(PP Ex . No 6)
Legend
8 C1ty l 1m,ts
Liberty Garden
Re nlon Parcels
I e f\2"12 11 CLG ,31S_::;ro.2cts·-v,c111 ty _maps·
-:-· ,.is oa·:e s_ 1.15 ;,Jo 14 s;o 1 50_h~er:y ~<;3rden_ae .. ,a· !"'"xd
Liberty Garden
Aerial
February 24, 2009
N
0 150 300 600 _ffi_
---c=====i Feet W
1 6 ,000
EXHIBIT F
(PP Ex. No 7)
Legend
c::J Liberty Garden
CJaty Umits
-Elevation
Liberty Garden
Topo Map
February 26 , 2009
0 75 150 300
Feet
1 3 ,250
~~
r -scr
hf::i:: T
\)t'IC\.p,...,-·f'f.0
SlC IJ. 1-2JH. II~ ....
.,,..-. ·'.··
(!J9-JJ/
t"-_A
--------------------gci;: ••• 1-2 :w. If S£. .....
fl'Ol,Dl!'AC:ATED)
-------1•' .~
I"-" 7
L.Ooa .. r,l
&--P
o\'
-J;."~~ ~' ~o~~~"~ 'iv<!!
co""~
,_f."P
/
/,-3,,1
/1~:
.. I / ' 2 /'/ ,f·.p''
.• /,
·' / ,-/ -,/-;----~ -'--+-~-~-
.---I--,. -~
I
(-o!ffe> i ~-r~~J
12
~.XIO ,.t l
--"'· --I
13'' ~-C: 1.1·• ., •. ·,,
1'-
(5;_',.".9 I "'-"
.;.1.J,.'(;L..._J
PAEUMINARY PLAT MAP
OF
LIBERTY GARDENS
A PORTION OF THE SE 1/4 OF SECTION 6 TOWNSI-F 22 N. RANGE 5 E. WM
KING COU'ffi'. WASHINGTON
I . ~,,_fl'l·)-i ... ~
p (N~ ,2•/ '!,~O t'='°'· ~ ,c.'-1 '
I . ,. ~
: !:.'(
.U : -~i:;~%~~!!..c:"':1fT
~\~ t~~t,C~-~~M~ ~1
VICHTY MAP
UEGAL DESCAPT10N ~~
-~' ~-flli'('r..,""'l•.IIUU'•C1:w>-, ..... .<Cllt.lAA.--rs.lr(JCOIOJ,(;
1':lr..rl'IAI-U~rtllW)(O •"".\......C l$':;#,V,N(,[91, a(IOl(.((1,,•n.-...ru,.. •1;1,1•lil•l 1
'---.J;
;,J \ ___ .,..,...--
" i ·:r,..
" i
--w~w-E-> ,,.,.,,.tn,1,
,,
d§Y
t"--A
&~,)
t ____ --~·-I
~
• __L ' ---h---~
j ~~;u c.-.,\:s' ,·,_1~ \J~'""',·1\
j I_-,,,<.. '-"""' ·,, ' ' ' ._;()~ . ,O
i----
\ ,.
\ I"-
\
-. I ,, "' "''"',;:> . ',
~-..---~
EXHIBIT ~
"''· \ '>,-' --'--' / ·---/ \
(PP Ex . No 10 )
~AL DAT).M
00,(:ffl(Jl"OJC,,JQO,~'(Ull ~Oo{:-
BENCHMRK•
~ [ll'".,.o, IOI CONC~r( ~I '° 1"-lflruc.{CTOI
/¥ ~-C U 2NOO,...,U:~ 1::..,11< 'WI. :O l
CL·-&,,.
r.EAOIAN• =-:1(~~1'1 WM'!' a»lrRO.
~BEARN:lS·
M s.. w, a rK Y 1/• Y ~ • 1'1 '11, --•" w....-,c __ ,r,wr w
ENOIEEfllf'l.N,tER
~~~~~~~.-:
~ .. 1,2,l 2'-' 81G
~·"(", Ill.I -.{ ... ,..,.. "Onut
OWNER/DEVEL~
~~cr:r'°"P\'~ ~..no,,o..-,..,-. ~)~-w.,,
IJTUTl:S/SEA'IICES
'"""~ 'O"A\o,,,q,-.,y
111.-c.. .... -~
(•?1)•.JOl W..2
l(N;to.HT'l' .... rot Cl"i"_,.C,
l w:l6 <,( 1211n. ~I
lltt<IOO<.-~\
(41~) :r.!~·MOC
.. .,u:,~u,u,o,:."'r'
1~1!>11TM~~
K'..i.[1,1,C, -
I IJOO]J;!l•'Jll
... ~~~~!>Ii~~
NOTES
«~['>II..(.. ..
(IIOO)J;!1·4 :J1
J ~<:l"rWA,~o(JW"~j\lK~~J')
/.'MO<v.{JC....:3<--lll'~' .... • ... ">IC>l..cl
• fa'.;l'M';l~~-·
I f'<IOf'O!.{l 1~...C ~ 4
'Ull,fl'OC:0,."'<lfll.N'.>Ml,\J,l,Ol",ll, ... r,ot,
u;!&<,,, flf....c,fl't(f . ll r..,; .. ~
~~u ~...,.,......,,or "'\i•H.J(l•u •
-O,,,C SllloC,S />o<"0-1,..,•,r.-..,-<,
~~ er_~~: ·:c;m
..., t.-.G ,.,..,r _, .. ,, .. ·~ f('l
IJ •·,'\.IV,,,l;.\l"""""!,IJ2,-.a l r
Tl ...-.uo(.(r:,1 91,-<H......,, .o,;0 TO<'QVU,i•••
1.,,,.1_r.wo,iM()o,l'-l'Olllf lt i,,.;:. XH--~ l ;IO,I
U-.:.:.f
4',Q ttCrt-AI.--..JL'll ----~· 602'l "''81.-.....
""*-'""'--\IIOOZ
o,,;; D.Jl.lOITo f ll'E °"""' OlJ r., 1n2, 1::41~ •uu.oE v
11£.0o10. ...... -.
('".?~I m -\1~,
[~~;:'"''
t •l~) 811-100)
BUFFER MAKE-UP T ASLE
,,,,..,.,.,. ... p.,-·1.ir.f,
C•n-c 4"" ~!J
i,.,rn:1>..w,;,-.>'Mt,1,
~:_•)
i.(i"e,ffl'll "i<i>i:<o~
1 " I"'~,.
-, •• ~,o :,,--
TRACT TABLE
-:..:•·J"""'""'I,>
\ .......... ui,;. ......... U-'l~'!l>V.I ,'.'o'C
.._...,I V',t D"'"l••¥ 2 ,:.1,T
-~' ,.v ~ .... -, "~:
fQ'" .. lbl'l<M.J,,/f,::,. ,,.,,'i'N \(
~~~
!
~ :::, Cf) z
~ i!:l ~~~ ~o~
:::, UJ
::J al I!! .J a.
"" 12! ~ 0 ~ 11;
a.@3:_l
:,i ~ ffl; ~ ~ ~ ~ 1· ~ ~ ~ ~ i
~ i
h h
,t+l· ~1 J l I -;; Il~t ·i
I
~ l~ . ,
~ "' ~ ~z :( ~ ~~ ~ ,J
:~H !i
!
i r
k
~
¥
~
~ ;1
I
" l
~
l"
tl ,·,-,. I ! .,A •,
l~~~";·<,,-~ ~
]C . l l
od-.~-t
i--s ;v>"' f
'll_ j -,
;'1; ...,
s:!
dmp, inc.
March 16, 2009
Rocale Timmons
City of Renton
1055 South Grady Way
Renton, WA 98057
EXHIBIT +f
( PP Ex. No tJ/Pr)
~.i_{;{:']t; •. .,Ji~~'.{;;~it
DALEY-MORROW-POBLETE, INC.
726 AUBURN WAY N.
AUBURN, WASHINGTON 98002
TELEPHONE: (253) 333-2200
FAX: (253) 333-2206
RE: LUA08-093 Liberty Gardens SEPA Jl;)peal -REVISED
Dear Ms. Timmons:
After reviewing the Environmental Revie1•· Committee Report, dated December
15, 2008 for the plat of Liberty Gardens, the Applicant submitted a timely SEPA
Appeal under the provisions of RMC 4-8-11 O (E) (3)(a). Since that time, we have
worked with Staff to clarify some of the original issues. This letter serves as a
REVISED SEPA appeal or a letter of clarification. Of the original seven issues,
we request that four be removed from the agenda.
Substantive Errors in Fact or Law
As required by RMC 4-8-110 (A)(2) the following sections describe the various
errors in fact or law that exist in the ERC report and the City record:
1. Lot Count -The Applicant has revised his Appeal Application. This issue
has been resolved with Staff. We ask that the Examiner remove this item
from the agenda.
2. RCW 43.21C.240 -RCW 43.21,:.240 prohibits a municipality from
imposing SEPA conditions for those project impacts that are already
adequately addressed under the vested development regulations.
Furthermore, Subsection (4) A states that a development regulation shall
be considered to adequately address an impact if the municipality, through
the planning and environmental review process under chapter 36.70A
RCW and this chapter, has identified the specific adverse environmental
impacts and:
(b) The legislative body of the municipality has designated as
Liberty Gardens SEPA Appeal
acceptable certain levels of service or development standards required or
allowed by chapter 36.70A RCW.
Under these provisions, the Applicant objects to the proposed mitigation
measures described under Part T'.',10 of the ERC Report,
Subsection B.
-1. 2001 DOE Storm Water Manual -Staff has conditioned the
project to use the 2001 DOE storm water manual in preparation of
the Temporary Erosion Control Plan. The Application is vested to
the King County 1998 SWDM. This vested document established
the need for, and the regulation of, Erosion Control Plans.
Compliance with the applicable manual is mandatory under the
vested development standards and no unique adverse
environmental impact has been identified to justify the modification
of the adopted standards. We ask that the condition be stricken
from the SEPA recommendation.
2. Restrictive Covenant -The City has required the imposition of a
restrictive covenant restricting the separate sale of all sensitive
area tracts. While we still disagree with the condition, this issue
has been resolved with Staff. We ask that the Examiner remove
this item from the agenda.
3. 5-year Monitoring -The City has required a 5-year monitoring and
maintenance plan be established or the wetland mitigation areas.
While we still disagree with the condition, this issue has been
resolved with Staff. We ask that the Examiner remove this item
from the agenda. It should still be noted however that the vested
code addresses this issue and the condition should not be part of
the SEPA mitigation (RCW 43.21C.240).
4. Maintenance Surety Devises -The City has required a
maintenance surety devise or financial guarantee be provided for
the proposed wetland mitigation. As indicated earlier, RCW
43.21C.240 prohibits a municipality from imposing SEPA
conditions for those project impacts that are already adequately
addressed under the vested development regulations. KCC
27A.40.080 (c) clearly requires financial guarantee be provided for
the proposed wetland mitigation. (see attached) This condition is
not appropriate under SEPA and should be removed.
As a subset of this proposed condition, it should be noted that
STAFF has attempted to limit the format of financial guarantee that
is accepted by the City. (see Staff Report Language Page 8).
Under the vested codes, KCC 27 A.20.050 defines the full range of
Liberty Gardens SEPA Appeal -REVISED 2
options open to an applicant to warranty materials and
workmanship. "Surety bonds" are found in the center of the
approved list. It must be made clear to Staff that the full range of
approved options is available to the Applicant.
~ 5. 2005 King County Manual -Through SEPA, The City has
required the imposition of Level 3 flow control under the 2005 King
County Manual. RCW 43.21C.240 prohibits a municipality from
imposing SEPA conditions for those project impacts that are
already adequately addressed under the vested development
regulations. As stated earlier, this application was vested in
December of 2004. This is prior to adoption of the 2005 Storm
Water Manual. This application is subject to the 1998 KCSWDM.
(note the typo listed in the ERG report which refers to the 1993
manual) We ask that the Examiner correct the record to reflect the
appropriate vested document and remove the condition from SEPA.
We do not argue the need for additional flow control only the use of
a non-vested manual. The preliminary Storm water review found
that the adopted manuals adequately address all downstream
conditions through the imposition of level 3 flow control.
6. Secondary Access -Staff has clarified that this was not intended
as a SEPA condition. We ask that this issue be removed from the
agenda.
Thank you for your time, cooperation and understanding with this project. If you
require additional information, please do not hesitate to contact me at (253) 333-
2200.
Sincerely,
!
I
Ha sA. Korve
Planning Manager
DMP, Inc.
Liberty Gardens SEPA Appeal -REVISED 3
HansKorve
From: Jackovich, Mary (Mary.Jackov1ch@kingcounty.govJ on behalf of DOES, FGMU [FGMU.DDES@kingcounty.govJ
Sent Monday, March 16, 2009 6:43 AM
To: Hans Korve
Subjett: RE: Bonding -Question -I need an answer before Tuesday Please
Yes. King County does accept bonds as a form offmanc1al guarantee
Fron,: Hans Korve (mailto:hans@dmp-tnc.us]
Sent: Friday, March 13, 2009 11:31 AM
To: ODES, FGMU
Subject: FW: Bonding -QuesUon -I need an answer before Tuesday Please
I am curreutly out of the office. [ will return on Tuesday, Man:h 17th; if you have a financial guarantee inquiry, email fgniu.ddes@k.ingcounly.gov
-----Original Message-----
From: Hans Korve [mailto:hans@dmp-inc.us]
Sent: Friday, March 13, 2009 11:29 AM
To: ·carol.rogers@kJngcounty.gov'
Subject: FW: Bonding
Carol-
Page I of2
Can you confirm from your office that King County does accept bonds as a form of financial guarantee J know they are listed in the approved list in the code,
butt need it confirmed. In particular, Jam asking about the Bonding of a wetland mitigation area after construction (Ouring the monitoring period) Please read
the attached email for clarification.
r appreciate any help you can provide
Hans Korve
DMP Inc
-----Original Message---"-
From: Sp::ioner, Scott (mailto:Scott.Spooner@kingcounty.gov]
Sent: Friday, March 13, 2009 11:22 AM
To: Hans Korve
Cc: awill@sewallwc.com; Rogers, Carol
Subject: RE: Bonding
Mr. Korve.
Yes. I am confident that King County does accept bonds as a form of f1nanc1al guarantee related to critical areas mitigation or restoration However, I do not
deal with the processing/papeiwork side of the financial guarantees. I am an ecologist that determines the amount required to be paid as a financial guarantee
that the required mitigation/restoration will be implemented in the manner stated in an approved plan
I would suggest contacting Carol Rogers in the Financml Guarantee Managernent Unit of DOES, as Carol is the most appropriate person to confirm this
question with. Carol's phone number is (206) 296-7250 and her ema·11 address is 9aro!.rogers@king_county.gov. I have also cc:d her on this email so she is
aware that you might be contacting her
Let me know if you have any further questions related to critical areas m1tigationlrestoration requirements in King County.
Take care.
'Scott Spooner
Senior Ecologist
Critical Areas Section
Land Use Services Division
Kfr1g C.ounty DD[S
900 Oake~dolt' A~·f!nue SW
Re--nton, WA 98055
Phone: (106) 296·6634
Fax: (206) 296 7051
Fnom: Hans Korve [mailto:hans@dmp·inc.us]
Sent: Wednesday, March 11, 2009 12:53 PM
Tat: Spooner, Scott
3/16/2()09
Subject: FW: Bonding
Scott-
Page 2 of2
As indicated below, I am looking for some type of confirmation that ODES allows. has accepted and will continue to accept Bonds as a form of financial
guarantee. Specifically maintenance guarantees for wetland m11igat1on
The issue that has come up is that the sentence below -form
approved by the director" would allow the Director to eliminate the potential to use Bonds rather than another method of Guarantee.
Can you provide some darification on this issue?
Thank you
Hans Korve DMP Inc.
27A.20.050 Financial guarantee. "Financial guarantee" means a form cf financial security posted
to ensure timely and proper completion of improvements, to ensure compliance with the King County Code,
and/or to warranty materials, workmanship of improvements, and design. Financial guarantees indude
assignments of funds, cash deposits, surety bonds. and/or other forms of financial security acceptable to the
director. For the purposes of this title, the terms performance guarantee. mamtenance guarantee and defect
guarantee are considered sub-categories of financial guarantee. {Ord. 12020 § 7, 1995).
27A.30.020 Financial guarantees-form and amount Financial guaranlees shall be in a form
approved by the director, in consultation with the department of natural resources and parks, department of
transportation, the prosecuting attorney's office, and other affected agencies. The amounts of the financial
guarantees shall be based on the schedules appropriate to the required work which are updated on a
periodic and frequent basis to ensure that the amount fully captures likely costs. Financial guarantees shall
also require a contingency in an amount to be determined by the director. (Ord. 14199 § 249, 2001: Ord.
12020 § 13, 1995).
-----Original Message-----
From: Aaron Will [mailto:awill@sewallwc.com]
Sent: Wednesday, March 11, 2009 12:20 PM
To; 'Hans Korve'
Subject: Bonding
Hans,
Per our previous phone conversation I do believe King County has and does allow the use of Bonds as a financial garuntcc for mitigation project">.
If you need written confinnation from the county that it is an acceptable means than I would start with Scott Spooner. I le should be able to direct
you to the person who might be able to fulfill your request. His e-mail address is.
S cott.sp_l ,mie(f{ki n gcoun ty. gov
Let me know if you have any questions.
Aaron
J. Aamn Will
WeHand Scientist
Sewall Wetland Consulting, Inc.
27641 Covington Way SE #2
Covington, WA 98042
(P) 253.859.0515
(F) 253.852.4732
3/16/2009
27A20.010 -27A20.060
Sections:
27A20.010 Applicant.
27A.20.020 Default.
27A20.030 Department.
27A.20.040 Director.
27A.20.050 Financial guarantee.
27A.20.060 Guarantor.
Chapter-27A.20
DEFINITIONS
FINANCIAL GUARANTEES
27A.20.010 Applicant. "Applicant" means the person or entity who is required to post the financial
guarantee. (Ord. 12020 § 3, 1995).
27A.20.020 Default. "Default" means the failure to:
A. comply wrth financial guarantee conditions;
B. complete, in the specified time, the required improvements in accordance with the King County
Code and with approved project plans and condrtions; or
C. maintain, for the specified period of time. the required improvements in accordance with the King
County Code and with approved project plans and conditions. (Ord. 12020 § 4. 1995).
27 A.20.030 Department. "Department"' means the King County department of development and
environmental services or its successor organization. (Ord. 12020 § 5, 1995).
27 A.20.040 Director. "Director' means the director of the King County department of development
and environmental services or his/her designee. (Ord. 12020 § 6, 1995).
27A.20.050 Financial guarantee. "Financial guarantee" means a form of financial security posted
to ensure timely and proper completion of improvements, to ensure compliance with the King County Code,
and/or to warranty materials, workmanship of im rovements, and design. Financial guarantees include
assignments of funds, cash deposits sure! bonds and/or other forms of financial security acceptable to the
director. For the purposes of this title, the terms performance guarantee, maintenance guarantee and defect
guarantee are considered sub-categories of financial guarantee. (Ord. 12020 § 7, 1995).
27 A.20.060 Guarantor. "Guarantor' means a bank or other acceptable entity which issues the
financial guarantee. (Ord. 12020 § 8, 1995).
King County 12-95)
27A---4
ADMINISTRATION 27A.30.080 -27A.30.100
C. Unless otherwise specifically indicated in the King County Code, perfonnance guarantees shall
require actual construction and installation of requir,cd improvements within two years after recording for final +
subdivision, two years after recording for short subdivision, one year after right-of-way pennit issuance or six
months after temporary building occupancy issued, for a building pennit. The time limit for perfonnance
guarantee compliance may be extended by six months at the directors discretion, if circumstances beyond
the control of the applicant warrant an extension. The request for an extension shall be in writing,
accompanied by a schedule for completion of remaining work. (Ord. 12020 § 19, 1995).
27A.30.090 Maintenance and defect guarantees authorized. A. The department is authorized to
require all applicants to post a maintenance guarantee and/or defect guarantee warranting the successful
operation and maintenance of improvements, and guaranteeing the workmanship, materials, and design
used in construction of improvements required by the conditions of any pennits or approvals issued pursuant
to titles 9, 14, 16, 19, or 21A; (or their successors) and assuring compliance with the King County Code.
B. Unless otherwise specifically indicated in the King County Code, all maintenance guarantees -}('
and defect guarantees shall guarantee successful operation, workmanship, materials, and design of
required facilities for a period of two years following final inspection and approval of improvements.
C. Inspections of facilities required pursuant to Titles 9, 14, 16, 19, or 21A (or their successors)
should be scheduled by the appropriate department approximately forty-five days prior to the end of the two
year maintenance and/or defect period. (Ord. 12020 § 20, 1995).
27 A.30.100 Default. A. Detennination of default shall be made by the department after an
inspection has indicated that improvements need to be corrected or completed. In the event of failure to
comply with any of the conditions and tenns of the pennits and/or approvals covered by this title, the director
shall notify the applicant and guarantor in writing of the default. If satisfactory assurance is not received by
the department within a time period detennined by the director, that conditions will be appropriately
corrected, the department may:
1. order the applicant to perform all necessary corrective work, and/or
2. demand payment on the financial guarantee(s). Nothing in this title shall limit the ability of
King County to enforce or otherwise compel compliance with conditions of any county pennit or approval in
accordance with any enforcement provision set forth in Title 23 of the King County Code.
B. The guarantor shall be responsible, up to the limits of the financial guarantee, for the payment of
any and all necessary costs and expenses that have been or will be incurred or expended by King County in
causing any and all such required work to be done. In the event that total costs associated with the required
work exceed the guarantee amount, the applicant shall remain responsible to King County for the payment
of any remaining amount.
C. In the event of default, King County may contract with a third party to complete work required
pursuant to this title. (Ord. 12020 § 11, 1995).
(King County 6-98)
27A--8
27A.40.070-27A.40.100 FINANCIAL GUARANTEES
27A.40.070 Landscaping. A. Pliorto receiving a temporary or permanent occupancy certificate for
any building or structure for which Title 21A requires landscaping, an applicant shall provide the required
performance guarantee to secure the completion ano improvement of required landscaping, in accordance
with approved site plan, within three months following issuance of the building or buildings temporary or
permanent occupancy certificate, whichever comes first.
B. Performance guarantees for landscaping required pursuant to K.C.C. 21A.16 shall be sufficient
to cover the cost of conformance with conditions of the permit, and shall be required for a period of two
years after the planting or transplanting of vegetation to insure proper installation, establishment and
maintenance. This time period may be extended by one year by the director, if necessary to cover a
planting and growing season.
C. The director may extend the time limit for compliance with the above landscaping requirement up
to one year after issuance of the occupancy certificate if circumstances beyond the control of the applicant
warrant an extension. The request for an extension shall be in writing, accompanied by a schedule for
completion of remaining work. (Ord. 12020 § 27, 1995).
27A.40.080 Sensitive areas. A. Financial guarantees for mitigation required pursuant to K.C.C.
chapter 21A.24 shall be sufficient to guarantee that all required mitigation measures will be completed no
later than the time established by King County in accordance with K.C.C. chapter 21A.24.
B. Performance and maintenance guarantees shall also be required for restoration of a sensitive
area or buffer not performed as part of a mitigation or maintenance plan except that no financial guarantee
shall be required for minor stream restoration carried out pursuant to K.C.C. chapter 21A.24.
C. For maintenance guarantees associated with mitigation, corrective work, restoration or
enhancement, the financial guarantee shall be sufficient to cover the time and cost to guarantee satisfactory
workmanship, materials and performance of structures and improvements required by K.C.C. chapter
21A.24 and any monitoring of those structures and improvements required by approved plans and
conditions.
D. Public development proposals shall be relieved from having to comply with the provisions of this
section if public funds have previously been committed for mitigation, maintenance, monitoring or
restoration. (Ord. 13189 § 9, 1998: Ord. 12020 § 28, 1995).
27A.40.090 Section 309 financial guarantees. Financial guarantees required pursuant to Section
309 of the King County modifications to the current Uniform Building Code shall be in the form of cash
deposited with the director, assignment of funds apprnved by the director, or in an irrevocable escrow in an
amount sufficient to restore the building and site, ar,d to perform corrective work required by Title 16 of the
King County Code. (Ord. 12020 § 29, 1995).
27A.40.100 Moved and temporary buildings. Financial guarantees required with respect to moved
or temporary buildings pursuant to Section 104 {e) of the King County modifications to the current Uniform
Building Code shall be in the form of cash deposited with the director, assignment of funds approved by the
director, or in an approved irrevocable escrow in a sufficient amount to be determined by the director. (Ord.
12020 § 30, 1995).
(King County 6-98)
27A-11
*
21A.24.125 -21A.24.130 ZONING
21A.24.125 Avoiding impacts to critical areas.
A. An applicant for a development proposal or alteration, shall apply the following sequential
measures, which appear in order of priority, to avoid impacts to critical areas and critical area buffers:
1. Avoiding the impact or hazard by not taking a certain action;
2. Minimizing the impact or hazard by:
a. limiting the degree or magnrtude of the action with appropriate technology; or
b. taking affirmative steps, such as project redesign, relocation or timing;
3. Rectifying the impact to critical areas by repairing, rehabilrtating or restoring the affected critical
area or its buffer;
4. Minimizing or eliminating the hazard by restoring or stabilizing the hazard area through
engineered or other methods;
5. Reducing or eliminating the impact or hazard over time by preservation or maintenance
operations during the life of the development proposal or alteration;
6. Compensating for the adverse impact by enhancing critical areas and their buffers or creating
substitute critical areas and their buffers; and
7. Monitoring the impact, hazard or success of required mrtigation and taking remedial action.
B. The specific mrtigation requirements of this chapter for each critical area or requirements
detenmined through the resource mitigation reserves program apply when compensation for adverse impacts
is required by the sequence in subsection A. of this section. (Ord. 15051 § 149, 2004).
21A.24.130 Mitigation and monitoring.
A. If mrtigation is required under this chapter to compensate for adverse impacts, unless otherwise
provided, an applicant shall:
1. Mrtigate adverse impacts to:
a. crrtical areas and their buffers; and
b. the development proposal as a result of the proposed alterations on or near the critical areas;
and
2. Monitor the performance of any required mrtigation.
B. The department shall not approve a development proposal until mitigation and monrtoring plans
are in place to mrtigate for alterations to crrtical areas and buffers.
C. Whenever mrtigation is required, an applicant shall submit a critical area report that includes:
1. An analysis of potential impacts;
2. A mrtigation plan that meets the specific mrtigation requirements in this chapter for each critical
area impacted; and
3. A monrtoring plan that includes:
a. a demonstration of compliance wrth thi, title;
b. a contingency plan in the event of a failure of mitigation or of unforeseen impacts if:
(1) the department determines that failure of the mitigation would result in a significant impact on
the crrtical area or buffer, or
(2) the mrtigation involves the creation of a wetland; and
c. a monrtoring schedule that may extend throughout the impact of the activfy or, for hazard
areas, for as long as the hazard exists.
D. Mitigation shall not be implemented until after the department approves the mrtigation and
monitoring plan. The applicant shall notify the department when mrtigation is installed and monrtoring is
commenced and shall provide King County with re;,sonable access to the mrtigation for the purpose of
inspections during any monitoring period.
E. If monitoring reveals a significant deviation from predicted impact or a failure of mitigation
requirements, the applicant shall implement an approved contingency plan. The contingency plan constrtutes
new mrtigation and is subject to all mitigation including a monitoring plan and financial guarantee
requirements. (Ord. 15051 § 150, 2004: Ord. 10870 § 460, 1993).
(King County 12-2008)
21A-216
*
CRITICAL AREAS 21A.24.133 -21A.24.160
21A.24.133 Off-5ite mitigation.
A. To the maximum extent practical, an applicant shall mitigate adverse impacts to a wetland,
aquatic area, wildlife habitat conservation area or wildlife habitat network on or contiguous to the
development site. The department may approve rrntigation that is off the development site if an applicant
demonstrates that:
1. It is not practical to mitigate on or contiguous to the development proposal site; and
2. The off-site mitigation will achieve equivalent or greater hydrological, water quality and wetland
or aquatic area habitat functions.
B. When off-site mitigation is authorized, the department shall give priorfy to locations within the
same drainage subbasin as the development proposal site that meet the following:
1. Mitigation banking sites and resource mitigation reserves as authorized by this chapter;
2. Private mitigation sites that are established in compliance with the requirements of this chapter
and approved by the department; and
3. Public mitigation sites that have been ranked in a process that has been supported by ecological
assessments, including wetland and aquatic areas established as priorities for mitigation in King County
basin plans or other watershed plans.
C. The department may require documentation that the mitigation site has been permanently
preserved from future development or alteration that would be inconsistent with the functions of the
mitigation. The documentation may include, but' is not limited to, a conservation easement or other
agreement between the applicant and owner of the mitigation site. King County may enter into agreements
or become a party to any easement or other agreement necessary to ensure that the site continues to exist in
its mitigated condition.
D. The department shall maintain a list of sites available for use for off-site mitigation projects.
E. The department may develop a program to allow the payment of a fee in lieu of providing
mitigation on a development site. The program should address:
1. When the payment of a fee is allowed considering the availabilfy of a site in geographic
proximity with comparable hydrologic and biological functions and potential for future habitat fragmentation
and degradation; and
2. The use of the fees for mitigation on public or private sites that have been ranked according to
ecological criteria through one or more programs that have included a public process. (Ord. 15051 § 151,
2004).
21A.24.137 Resource mitigation reserve. The department may approve mitigation to
compensate for the adverse impacts of a development proposal to critical areas through the creation and
approval of a resource mitigation reserve. The use of a resource mitigation reserve to compensate for
unavoidable impacts to a critical area is not allowed in the agricultural production districts if the purpose is to
compensate for development outside of the agricultural production districts. (Ord. 15051 § 152. 2004).
21A.24.140 Financial guarantees. Financial guarantees shall be required consistent with the
provisionsofTitle27A. (Ord.12020§54, 1995: Ord.10870§461, 1993).
21A.24.160 Critical area markers and signs.
A. Development proposals shall include pennanent survey stakes delineating the boundary between
adjoining property and critical area tracts, using iron or concrete markers as established by current survey
standards.
B. The applicant shall identify the boundary between a critical area tract and contiguous land with
permanent signs. The department may require signs and fences to delineate and protect critical areas and
critical area buffers that are not in critical area tracts. (Ord. 15051 § 154, 2004: Ord. 10870 § 463, 1993).
(King County 12-2008)
21A-217
.... ()(-5'-f D
King County
Department of Development and Environmental Services
Determination Of Non-Significance (DNS)
for
Liberty Gardens (DDES File No. L04P0034)
Date of Issuance:
Project:
Location:
King County Permits:
County Contact:
Proponent:
Zoning: R-4
June 20, 2008
Request is to subdivide 8.95 acres, zoned R-4 into 36 lots for single
family detached residences and a tract for combined drainage and
recreation. The lots range from approximately 5,900-9,350 square
feet.
The property is located on 162nd Avenue SE, approximately 1/, mile
south of the 162nd Avenue SE and SE l 36'h Street intersection.
Formal Plat
Chad Tibbits, Project Manager III
chad. ti bbi ts@metrokc.gov
(206) 296-7194
David Petrie
811 S. 273,d Ct.
Des Moines, WA 98198
253-946-6619
Community Plan: Newcastle
Drainage Subbasin: Lower Ceder River
Section/Township/Range: 14-23-05
Notes:
A. This finding is based on review of the project site plan, environmental checklist, level one
drainage analysis, and other documents in the file.
B. The drainage facilities will be designed in accordance with the 1998 King County Surface
Water Design Manual.
C. Issuance of this threshold determination does not constitute approval of the permit. This
proposal will be reviewed for compliance with all applicable King County codes which regulate
development activities, including the Uniform Fire and Building Codes, Road Standards, Surface
Water Design Manual, and the Sensitive Areas Regulations.
D. As a requirement of compliance with the 1993 King County Road Standards, the proposed
subdivision is required to extend, or financially participate with other developers, 162nd Avenue SE
--from the subdivision boundary to SE 144th Street in general compliance with preliminary plan
and profile drawings submitted to the Department. With Code authority (the 1993 KCRS, adopted
by reference at KCC 14.42 with Ord. 11187) outside ofSEPA-related transportation codes (KCC
14.80) to require this improvement, a condition of approval to construct/share in the cost of the
construction --via a Mitigated DNS --is not needed nor appropriate. Therefore, the requirement
will be incorporated in staffs recommended conditions of approval report. Final engineering
t"·~""'~ Liberty Gardens -L04P003.;':"· '·
June 20, 2008
Page 2
details of the road alignment and associated improvement is pending upon the submittal of
engineering plans following a grant of preliminary approval.
Threshold Determination
The responsible official finds that the above described proposal does not pose a probable significant
adverse impact to the environment.
This finding is made pursuant to RCW 43.21 C, KCC 20.44 and WAC 197-11 after reviewing the
environmental checklist and other information on file with the lead agency and considering
mitigation measures which the agency or the applicant will implement as part of the proposal. The
responsible official finds this information reasonably sufficient to evaluate the environmental
impact of this proposal.
The lead agency has determined that the requirements for environmental analysis, protection, and
mitigation measures have been adequately addressed in the development regulations and
comprehensive plan adopted under chapter 36.70A RCW, and in other applicable local, state, or
federal laws or rules, as provided by RCW 43.21C.240 and WAC 197-11-158. Our agency will not
require any additional mitigation measures under SEP A.
Comments and Appeals
Written comments or any appeal of this threshold determination must be stamped received by King
County before 4:30 PM on July 7, 2008. Appeals must be accompanied by a nonrefundable filing
fee. Please reference the file numbers when corresponding.
Appeals must be in writing and state the perceived errors in the threshold determination, specific
reasons why the determination should be reversed or modified, the harm the appellant will suffer if
the threshold determination remains unchanged, and the desired outcome of the appeal. If the
appellant is a group, the harm to any one or more members must be stated. Failure to meet these
requirements may result in dismissal of the appeal.
Comment/appeal deadline:
Appeal filing fee:
Address for comment/appeal:
Responsible Official:
e Bottheim, Supervisor
ent Planning Section
d Use Services Division
TD-LOGO 2/98
4:30 PM on July 7, 2008
$250 check or money order made out to the King
County Office of Finance
King County Land Use Services Division
900 Oakesdale Avenue SW
Renton, WA 98057-5212
ATTN: Current Planning Section
(o· ?-D
Date
,.
® .otice
of Decision-
Department of Development and Environmental Services
Land Use Services Division
SEPA Threshold Determination
and
Notice of Recommendation
& Hearing
900 Oakesdale Avenue Southwest
Renton, Washington 98057-5212
File No. L04P0034 Project Name: Liberty Garde s Subdivision
ODES Project Manager: Chad Tibbits, 206-296-7194
Email: chad.tibbits@metrokc.gov
~~:~
j/ ·-,~. ,:,;,; -, ~
Applicant:
Project Location
Project Description:
Permits Requested
David Petrie
811 S. 273'd Ct.
Des Moines, WA 98198
253-946-6619
,,-, 1/""i,..~
.,. ~ I'':-1 }0
• ·1 )'>
;}•
The property is located on 162"d Avenue SE, approximately'!. mile
south of the 162nd Avenue SE and SE 1361
h Street intersection.
Subdivision of approximately 8.95 acres into 36 lots for the
development of single family detached residences in the R-4 zone.
The proposed lots range in size from approximately 5,900 to 9,350
square feet.
Formal Subdivision
Department Recommendation to the Hearing Examiner Approve, subject to conditions
Date of Public Hearing July 17, 2008, 9:30 am
ODES Hearing Room -first floor
900 Oakesdale Ave SW
Renton, WA 98057-5212
SEPA Threshold Determination Determination of Non-Significance (DNS)
Issued June 20, 2008
The Department of Development and Environmental Services (DOES) will issue a written report and recommendation
to the Hearing Examiner two weeks prior to the scheduled public hearing. Persons wishing to receive a copy of the
report should contact DOES at the address listed below. Following the close of the public hearing. the Hearing
Examiner will issue a written decision which may be appealed to the Metropolitan-King County Council. Appeal
procedures will be stated in the Examiner's written decision.
Any person wishing additional information on this proposed project should contact the Project Manager at the phone
number listed above. Written comments may also be submitted to DOES.
A public hearing as required by law will be held to consider the approval of this application. If the Renton School
District announces a district-wide school closure due to adverse weather conditions or similar area emergency, the
public hearing on this matter will be postponed. Interested parties will be notified of the time and date of the
rescheduled hearing. Any questions regarding postponements and rescheduling can be directed to the Hearing
Examiner's Office at (206) 296-4660.
Comment/Appeal Procedure on SEPA Threshold Determination:
Comments on this SEPA determination are welcome. This SEPA determination may also be appealed in writing to
the King County Hearing Examiner. A notice of appeal must be filed with the Land Use Services Division at the
address listed below prior to 4:30 p.m. on July 7, 2008. and be accompanied with a filing fee of $250.00 payable to
the King County Office of Finance
If a timely Notice of Appeal has been filed. the appellant shall also file a Statement of Appeal with the Land Use
Services Division at the address listed below prior to 4:30 p.m. on July 14, 2008. The Statement of Appeal shall
identify the decision being appealed (including the file number) and the alleged errors in that decision. Further, the
Statement of Appeal shall state: 1) specific reasons why the decision should be reversed or modified; and 2) the
harm suffered or anticipated by the appellant, and the relief sought. The scope of an appeal shall be based on
matters or issues raised in the Statement of Appeal. Failure to timely file a Notice of Appeal, appeal fee or Statement
of Appeal, deprives the Hearing Examiner of jurisdiction to consider the appeal.
Appeals must be submitted to the Department of Development and Environmental Services (ODES) at the following
address:
Date Mailed: June 20, 2008
DDES--Land Use Services Division
Attn: Permit Center
900 Oakesdale Avenue Southwest
Renton, Washington 98057-5212
If you have any questions regarding the appeal procedures, please contact the Planner at the phone number listed above.
If you require this material in braille, audio cassette, or large print, call (206) 296-6600 (voice) or (206) 296-7217 (TTY).
G. NEIGHBORHOOD CHARACTERISTICS:
The property is located in an urban area of King County. Surrounding properties to the
southeast are all single-family detached residences. Liberty High School baseball field is
located northeast of the property. Properties directly adjacent to this site to the north, west and
east are undeveloped. Currently this site is undeveloped. The property is located southwest of
Liberty High School and east of the City of Renton.
H. SUBDMSION DESIGN FEATURES:
I. Lot Pattern and Density: The proposed lot and street layout is in conformance with
King County Code (KCC) 21A (Zoning). The plat's proposed density of 4 dwelling
units per acre is in conformance with KCC 21.A and the R-4 zone.
2. Internal Circulation: The site will access 162nd Avenue SE, and will be served by SE
140th Place, l 63'd Avenue SE and SE 141 '' Place all urban minor access roads ending in
a cul-de-sac.
3. Roadway Section: The roads will be designed and constructed to the urban standards
of the 1993 King County road Standards.
4. Drainage: The Liberty Gardens subdivision is located in the Orting Hill Subbasin
of the Lower Cedar River basin. The site is subject to the Level II flow control and
Basic water quality requirements of the 1998 KCSWDM. Level III Flow Control
is proposed by the applicant to address downstream drainage problems in the area.
The existing site drainage generally sheet flows from the northeast to the southwest,
leaving the site along the south property line in an existing water course. The flow
continues offsite to the southwest, combining with another drainage course in the
unopened l 62"d Ave SB R/W. The downstream continues south through a ponding
area in the unopened R/W, to SB 144th Street. The drainage then enters a cross
culvert under SE 144th St and 1;urns to the west along the south side of SE 144th St in
an enclosed pipe system. The enclosed pipe system continues west, past 156th Ave
SE, continuing west eventually outfalling to Tributary 0307. Tributary 0307 then
turns south and outlets to the Cedar River.
The proposal is to collect most runoff from the project site and direct it to a single
detention and water quality facility located in Tract B in the southwest portion of
the site. Separate underground detention/water quality facilities are proposed for
the offsite road improvements. A Level III Downstream Drainage Analysis
prepared by Ed McCiuthy P.E., was received July 02, 2007. A letter with
additional Recommended Stormwater Mitigations was received March 11, 2008.
Several capacity and drainage problems were identified in the area. The applicant
is proposing Level III Flow Control to address the downstream drainage problems.
This is appropriate mitigation per Core Requirement 2 of the KCSWDM. The
applicant is also proposing to construct 162nd Ave SE to connect to SE 144th St,
including related offsite drainage improvements.
I. TRANSPORTATION PLANS:
1. Transportation Plans: The subject subdivision is not in conflict with Transportation,
Non-motorized and Trails plan.
2. Subdivision Access: The site will gain access from.162"d Avenue SE by the internal
plat road of SE 140th Place.
3. Traffic Generation: It is expected that approximately 360 vehicle trips per day will be
generated with full development of the proposed subdivision. This calculation includes
service vehicles (i.e., mail delivery, garbage pick-up, school bus) which may currently
serve this neighborhood, as well as work trips, shopping, etc.
4 FILE NO: L04P0034
2. Community Plans: The subject subdivision is located in the Newcastle Community
Plan. The subject subdivision is not in conflict with the goals, guidelines and
policies of the Newcastle Community Plan.
M. STATUTES/CODES:
If approved with the recommended conditions in this report, the proposed development will
comply with the requirements of the County and State Platting Codes and Statutes, and the
lots in the proposed subdivision will comply with the minimum dimensional requirements
of the zone district.
N. CONCLUSIONS:
The subject subdivision will comply with the goals and objectives of the King County
Comprehensive Plan and will comply with the requirements of the Subdivision and Zoning
Codes and other official land use controls of King County, based on the conditions for final
plat approval.
0. RECOMMENDATIONS:
It is recommended that the subject subdivision, revised and received May 2, 2008, be
granted preliminary approval subject to the following conditions of final approval:
I. Compliance with all platting provisions of Title 19A of the King County Code.
2. All persons having an ownership interest in the subject property shall sign on the
face of the final plat a dedication that includes the language set forth in King
County Council Motion No. 5952.
3. The plat shall comply with the base density and minimum density requirements of
the R-4 zone classification. All lots shall meet the minimum dimensional
requirements of the R-4 zone classification or shall be shown on the face of the
approved preliminary plat, whichever is larger, except that minor revisions to the
plat which do not result in substantial changes may be approved at the discretion of
the Department of Development and Environment Services.
4.
5.
6.
7.
Any/all plat boundary discrepancy shall be resolved to the satisfaction ofDDES
prior to the submittal of the final plat documents. As used in this condition,
"discrepancy" is a boundary hiatus, an overlapping boundary or a physical
appurtenance which indicates an encroachment, lines of possession or a conflict of
title.
All construction and upgrading of public and private roads shall be done in
accordance with the King County Road Standards established and adopted by
Ordinance No. 11187, as amended (1993 KCRS).
The applicant must obtain the approval of the King Cowity Fire Protection Engineer
for the adequacy of the fire hydrant, water main, and fire flow standards of Chapter
17.08 of the King Cowity Code.
The drainage facilities shall meet the requirements of the 1998 King County
Surface Water Design Manual (KCSWDM). The drainage design shall meet
Level m Flow Control and Basic Water Quality requirements in the KCSWDM.
The following road improvements are required to be constructed according to the
1993 King County Road Standards(KCRS): (Note that portions of the b~low 162nd
Ave SE road improvements are also conditioned with the plat of Threadgill
L05P0026 or to be conditioned with the plat of Cavalla L06P0001.)
140th Place and 163'd Ave SE shall be improved at a minimum to the urban
subaccess street standard. The portion of SE 140th PL east of 163n1 Ave SE(
7 FILE NO: L04P0034
to the cul-d-sac) shall be improved at a minimum to the urban minor access
street standards.
b. SE 141" Place shall be improved at a minimum to the urban minor access
street standards.
c. FRONTAGE: 162"d Ave SE along the subdivision frontage shall. be
improved to the urban neighborhood collector standard on the east side of
the centerline. The west side shall be improved with an 11 ft min. driving
lane. A graded gravel shoulder shall also be required on the west side of
the frontage.
d. OFFSITE ROAD/WALKWAY IMPROVEMENTS: 162"a Avenue SE,
from the north subdivision boundary to SE 136tti Street shall be improved to
provide a minimum 22-feet of pavement (two I I-foot wide lanes for
vehicular traffic) together with one of ( or, combination -depending upon
the location) the following shoulder improvements for school-age
pedestrians on the east (plat) side of 162"d Avenue SE:
• A minimum eight (8) foot wide paved shoulder (for a total of 19-feet
of pavement from the centerline of 162"d Avenue SE, with 11-feet of
pavement on the west side of the centerline)
• An urban-type shoulder design: concrete curb, gutter and sidewalks
(for a total of 16-feet of pavement from the centerline of 162"d
Avenue SE, together with concrete curbs, gutters and sidewalks,
with 11-feet of pavement on the west side of the centerline)
• A minimum five (5) foot wide paved pedestrian walkway, together
with sufficient paving to install an extruded curb to provide a two (2)
foot shy distance between the edge line of the traveled-way and the
roadway-side face of the extruded curb, with the paved-width noted
for vehicle traffic.
• A graded gravel shoulder shall be provided on the west side of the
road the full limits of this section of 162nd Avenue SE.
e. OFFSITE ROAD/WALKWAY IMPROVEMENTS: 162"a Avenue SE,
from the south subdivision boundary to SE 144tti Street shall improved to a
minimum 22-foot paved width, plus urban shoulder improvements on the
east side of the roadway in general conformance with the conceptual
roadway improvement plans received March 11, 2008 or as approved by
DOES. Any design elements of the roadway alignment: plan or profile, that
requites either a variance reviewed through the office of the ODES
Development Engineer, or a Variance reviewed through the office of the
County Road Engineer, shall be subject to a requirement of having an
approved variance before the approval of the engineering plans. Any
plan/profile design elements that are not consistent with the KCRS, and are
not approved/conditionally-approved through one of the two variance
processes noted, shall require redesign.
• A graded gravel shoulder shall be provided on the west side of the road the
full limits of this section of 162nd Avenue SE.
• An existing water course enters the unopened l 62"d Ave SE R/W from the
west, at approximately the south property line(adjoining the north line of the
Gragg property at 16046 SE 142nd St). An appropriate inlet structure(cage
type or as approved by ODES), for this drainage course shall be designed
and shown on the engineering plans.
• The new drainage conveyance system for this improvement at l 62"d Ave SE
and SE l 44tti St shall be designed to route potential overflow to the west
8 FILE NO: L04P0034
areas for road improvements may be allowed per KC 21A.24. However
mitigation shall be required. Construction techniques such as retaining
walls maybe required at such crossings or improvements to limit impacts. A
final mitigation plan shall be required during engineering review.
f. Sensitive area tract boundaries shall be clearly marked with bright orange
construction and silt fencing prior to construction or site clearing activities.
The boundaries shall remain marked until construction is complete.
g. Hydrology may not be altered either during or after development. A
hydrology analysis may be required during engineering review to show how
the hydrology will be maintained after and during site development.
h. Work within the OHWM may require an HP A from the State Department of
Fish and Wildlife. It will be the applicant's responsibility to coordinate with
WDFW to determine if an HP A is needed.
1. The engineering plans shall be routed to Critical Areas Staff for review of
compliance to the above conditions.
Alterations to Streams or Wetlands
If alterations of streams and/or wetlands are approved in conformance with K.C.C.
21A.24, then a detailed plan to mitigate for impacts from that alteration will be
required to be reviewed and approved along with the plat engineering plans. A
performance bond or other financial guarantee will be required at the time of plan
approval to guarantee that the mitigation measures are installed according to the
plan. Once the mitigation work is completed to a ODES Senior Ecologist's
satisfaction, the performance bond may be replaced by a maintenance bond for the
remainder of the five-year monitoring period to guarantee the success of the
mitigation. The applicant shall be responsible for the installation, maintenance and
monitoring of any approved mitigation. The mitigation plan must be installed prior
to final inspection of the plat.
13. The following note shall be shown on the final engineering plan and recorded plat:
RESTRICTIONS FOR SENSITIVE AREA TRACTS AND SENSITIVE
AREAS AND BUFFERS
Dedication of a sensitive area tract/sensitive area and buffer conveys to the public a
beneficial interest in the land within the tract/sensitive area and buffer. This interest
includes the preservation of native vegetation for all purposes that benefit the public health,
safety and welfare, including control of surface water and erosion, maintenance of slope
stability, and protection of plant and animal habitat. The sensitive area tract/sensitive area
and buffer imposes upon all present and future owners and occupiers of the land subject to
the tract/sensitive area and buffer the obligation, enforceable on behalf of the public by
King County, to leave undisturbed all trees and other vegetation within the tract/sensitive
area and buffer. The vegetation within the tract/sensitive area and buffer may not be cut,
pruned, covered by fill, removed or damaged without approval in writing from the King
County Department of Development and Environmental Services or its successor agency,
unless otherwise provided by law.
The common boundary between the tract/sensitive area and buffer and the area of
development activity must be marked or otherwise flagged to the satisfaction of King
County prior to any clearing, grading, building construction or other development activity
on a lot subject to the sensitive area tract/sensitive area and buffer. The required marking
or flagging shall remain in place until all development proposal activities in the vicinity of
the sensitive area are completed.
No building foundations are allowed beyond the required 15-foot building setback line,
unless otherwise provided by law.
14. Suitable recreation space shall be provided consistent with the requirements of
K.C.C. 21A.14.180 and K.C.C. 21A. 14.190 (i.e., sport court[s], children's play
equipment, picnic table[s], benches, etc.).
10 FILE NO: L04P0034
L,_)Vv:
5 f'-lotYl ..