HomeMy WebLinkAboutMisc 0251 2 SIXTH STREET .SOUTH, SUITE 202, KIRKLAND, WA SB❑33
PH: (425) B27- 5995 Fx, (425) BZB-4B50
PD[3-WA[a PDG-WA.C❑M
City of Renton, Washington
w
RECEIVE
Preliminary Technical Information Report
For
Townhomos
4701 Talbot Road South
Renton, WA 98055
Poggemeyer Design Group, Project N
Date Description
II -
4 rlcl
/ONAL
I V EXPIRES 1/25/10%
Prepared under the direct supervision of
Todd A. Popelka, P.E., Washington Registration
No. 36425 for and on behalf of Poggemeyer
Design Group
Revisions:
Tu WNHC]ME5 - TIR PAnr I or 30
6/0412007
Table of Contents
Section 7 - Project Overview
Section 2 - Conditions and Requirements Summary
Section 3 -- Off -site Analysis
Section 4 - Flaw Control and Water Quality Facility Analysis and Design
Section 5 - Conveyance System Analysis and Design
Section 6 - Special Reports and Studies
Section 7 - Other Permits
Section 8 - ESC Analysis and Design
Section 9 - Bond Quantities, Facility Summaries, and Declaration of Covenant
Section 10 - Operations and Maintenance Manual
Appendix
Appendix A - Maintenance Instructions
Appendix B - Soils Report
Appendix C - Backwater Analysis Calculation Sheet
TowNHOMES -- T{R PAGE 2 OF 30
7/3 1 /20Q7
TECHNICAL INFORMATION REPORT (TIR) WORKSHEET
Project Owner: Y & L Enterprises, LLC
Address P.O.BOX 5757
Bellevue, WA 98006
Project Engineer: Todd Popelka, PE
Poggerneyer Design Group
512 Sixth Street South, Suite 202,
Kirkland, WA 98033
Ph: (425) 827- 5995 Fx_ (425) 828-4850
MILUNE
Subdivision
Short Plat
Grading
Commercial
Other Multi -family
---------------
- River
Stream
Critical Stream Reach
E - Dep ressions/Sw ales
Lake
(— Steep Slopes
DFW HPA
COIL 404
DOE Dam Safety
FEMA FloodpUn
COE Wetlands
F loodp l ain
Wetlands
Seep s/Sp rings
High Groundwater Table
Groundwater Recharge
- Other
Shoreline Management
Rockery
Structural Vaults
1_.. Other
PART 7 SOILS
Soil Type Slopes Erosion Potential Erosive Velocities
Alderwood Gravelly Sandy Loam 6 - 15 % Slight
TOWNHOMrs - TJR PAGE 3 ❑F 30
7/31 /2007
Additional Sheets Attached
TECHNICAL INFORMATION REPORT (TIR) WORKSHEET
REFERENCE
— Downstream An
'�O Additional Sheets attached
MINIMUM ESC REQUIREMENTS
DURING CONSTRUCTION
Sedimentation Facilities
V Stabilized Construction Entrance
v, Perimeter Runoff Control
V Clearing& Grading.Restrictions
V Cover Practices
Construction Sequence
Other
LIMITATIONISITE CONSTRAINT
MINIMUM ESC: REQUIREMENTS
AFTER CONSTRUCTION
Stabilize Exposed Surface
+� Remove and Restore Temporary ESC Facilities
fV Clean and Remove All Silt & Debris
Ensure Operation of Permanent Facilities
Flag Limits of'SAO and Open Space Preservation Areas
Other
Grass Lined Channel
Y Tank
Infiltration
Pipe System
Vault
Depression
Open Channel
Energy Dissipater i
Flow Dispersal
f Dry Pond
Wetland t_-_
Waiver
Wet Pond
St I---
Regional Detention
Brief Description of System
Operation: The system will include detention/ wet vault.
The vault outlet will tie to
an existing catch basin at the northeast corner of the adi2
Method of Analysis:
KCRTS Level 2
property to the west.
Facility Related Site Limitations
Reference Facility Limitation
Cast in Place Vault
i y Retaining Wall
s Rockery > 4' High
Structural on Steep Slope
Retaining Wall
Drainage Easement
Access Easement
Native Growth Protection Easement
Tract
r Other
TOWNHOMEE - TIR PAGE 4 OF 30
713 1_/20O7
l or a civil engineer under my supervision have visited the site. Actual site conditions as observed were incorporated into this
worksheet and the attachments. To the best of my knowledge the information provided here is accurate.
TowNHOMES - TIR PAGE 5 ❑F 30
7/3 1 /2007
Section 1 — Project Overview
The subject property is located on the west side of Talbot Road S, south of South 45th Place. The
property is totaling approximately 44,866 square feet (1.03 acres). Currently there is an existing single-
family house that will be removed prior to site development.
The proposal is to subdivide the parcel and develop approximately 20 townhouse residential units. The
units will be grouped into 3 structures with 2 buildings having 6 units each and 1 building having 8 units.
Each unit will have a two -car garage under the unit and there will be 5 guest parking stalls.
The proposed project is located in the SE Quarter of Section 31, Township 23N, Range 5E, WM, King
County, Washington and is shown on the vicinity map below.
Valeymedcal t .
Centel i Traffic F,9ap satellite H;'t1rio
Valsey N9E01c,31 �• N
Ce�tzr SE Carr Rd
G7
'Jal:ey bleoical
V N_
Gen!Br-ERGO D
C) i
F
5 43rd St U,
c7
a
f aL
3r
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a
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o
y e6�u
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- Gopper R>Ogl gpaRmPrslS
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s9
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r
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r
ae9Yt+W
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SE 9871!! S! ..
5 501h PI
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_ SE 1 eat+
S,5154 2007 Gaogle- uap Data @2007 NAVTER
Fil;.1 VICINITY MAP
The property is located within the Residential Multi -Family Comprehensive Plan land use designation
(RM-F zone). There is currently one residential structure on the property. The project proposes to
TuwN"oMES — TER PAGE 6 GF 30
W3112C707
demolish the existing house and subdivide the parcel and develop 20 townhouse residential units with the
associated access road from Talbot Road South and underground utilities.
Currently the runoff from the property sheet flows towards the western boundary of the site, which is its
natural discharge point. The runoff from the developed site (surface flow from the access driveway and
roof drains) and discharged through a conveyance system into the proposed detention/wet vault.
While the site project discharges primarily to the western side of the property, the flows combine before
leaving the site and will therefore be discharged at the natural location for this property. Currently a 12-
inch storm pipe is stubbed to the west property line the project proposes to utilize this conveyance
system.
Water quantity and quality will be required and will be accomplished via a detention/ wet vault.
The proposed development will contain 75% impervious (The maximum impervious surface allowed in the
RM-F zone). The remaining 25% will be landscaped area.
FiG.2 SCS SOIL SURVEY MAP
SCS Soils Map: Based on the King County Soil Survey the on -site soils are mapped as Alderwood
gravelly sandy loam (AgC) series, 6 to 15 percent slopes hydrologic class "C" (See Figure 2). Alderwood
series have slow permeability; runoff potential is slow to medium, and a moderate to severe erosion
hazard.
TOWNHOMEs - TIR PAGE 7 OF 30
7/3 1 /2007
TABLE 31,23 LQUIULENGE BETI< MEN SCS SOIL TITES AND KCRTS SOIL TY-RES
SCSSoil Type
SCS
Hydrologic
Soil Group
KCRTS Soil
Group
Notes
AIdenvwd � AgR, ,u C. A D)
C
Till
Arens Aldermod Material;A,nE. AmC
C
Till
Mren;s_ :1ere+r Material °A^'
d
tivtsva=_h
]
Beausite iEeC.'-0. Be:-,)
C
Till
c
Bellingham ;?
C
Till
3
6ri1_e_:3r,
C'
Till?
6uem.!cy
Till
t
Earlrrart ;E¢i
Till
?
Ed cwl:'{+_�`
TIII
3
Ev_ _I = E, Ev , D;D :- svC;
A:6
C,'as-h
1
i^. 3r:oai .,C. InA rD;
L
Kitsap tK-v , KpC. �pC;
Till
,Iaus �' ..SC,
G
G.-%w.E_h
1
Nz .cn iii8: I
'
:41'3511
Y,Till
t
Nirdterg iNg:
",- kNk
C
Till
3
L
Till
3
Dr-Js ;Dri
D
We -land
11rrda t s,
G�
ill
01 3 i C• C (DSC. C-,,F'i
C
Till
2
Pily^u:,+4;'-�"r
c
Till
3
Puw ;?u;
D
Till
3
PUY,30UP �P' y
a
Till
3
Ra'^ar=-a[:.?aD, Rai;, RaE)
Cmm,3sh
1
R_'Icn?Re,
D
Till
3
Salal tSa]
C
Till
3
Sawmarni=_h iShL�
D
Till
3
SeatOe tSk;
D
Re -.land
Shalcar iSm i
D
Till
3
Si ;?'�
c
Till
3
anchcmi=_h isc, Sr,
D
Till
3
Sultan iSlr;
D
Till
3
%t4tiila(Tu'i
D
Till
3
lhcf _dlrwllle th'r)•:
D
Till
3
F1Liru
1. 4 sl^ere o�nvash so s are saturated or unc�--dain at shsile depth ;e tee;) b f g Seal till. th:r shout,
be 7z-at=d as 0Il so-s,
2. Tnes,-= are tedro,k so s, ht; alib€aticn cf HSPF by Krg County Q420NM kLms becrock scils
o I-> vc— similar hydrkgic r_spcnse :o d soi s.
3. Tres are Juvlal sells. sane & Mich are undi-trialn by glaciat'i: o,, hwa a seascna y higi hater
tke. i:� the atrer�,e of cetsiled s;tti}, :� se sciis should be_atPd as till sots.
4. Gu: k. ey soils He'd rn the iyat permekilitr Cscvcla madflcsr. i 'Vd-dogi: response is
assLm--..o be s m ar m that of zi sods.
TOWNHOME9 — TIR PAGE 8 OF 30
713 1 /2007
Section 2 — Conditions and Requirements Summery
The following summary describes how this project will meet the eight "Core Requirements" and the
"Special Requirements" that apply:
Core Requirements
1. Discharge at the natural location: This site currently discharges to the western end of the site_
The proposed drainage system for this project will discharge to the existing location_
2. Off -site Analysis: A Level 1 off -site analysis was completed for this project.
3. Core Requirement #3: Runoff Control
Runoff control will be provided for the development via a detention vault. The on -site detention
facility has been sized to release the developed discharge at the pre -developed rate for the
proposed development.
4. Flow control: The proposed Level 2 detention vault is sized to meet the requirements of the
KCSWDM using the KCRTS program.
5. Conveyance system: Flows will be conveyed using catch basins and 12" pipe system. No
onsite analysis of the conveyance system is included with this preliminary TIR. Off -site
conveyance analysis is attached.
6. Erosion and sedimentation control: TE=SC plans will be submitted along with the engineering
plan submittal and is not included in this preliminary TIR.
7. Maintenance and Operations: Included in this preliminary report, Appendix A.
8. Financial guarantees and liability: Not included in this preliminary report.
9. Water Quality: The new impervious surface subject to vehicular traffic is greater than 5,000
square feet for this project. As a result water quality treatment is required_ Water quality is to be
provided with a wet vault and sized according to KCSWDM.
Special Requirements
1. Other adopted area -specific requirements: Level 2 Flow Control will be required.
2. FloodplainlFloodway delineation: Not applicable.
3. Flood protection facilities: Not applicable.
4. Source controls: Not applicable.
5. Oil Control: Not applicable.
Section 3 — Off -site Analysis
See the Level 1 Downstream Analysis provided in this report.
Resource Review: The King County IMAP program was examined for mapped sensitive areas, both on -
site and adjacent off -site features. Sensitive areas include streams, wetlands, erosion, and seismic
hazards located on -site and downstream within 114 mile of the project area.
Streams:
None located within the one quarter mile area
Wetlands:
None located within the one quarter mile area
Erosion:
None located within the one quarter mile area
Landslide:
None located within the one quarter mile area
Seismic:
None located within the one quarter mile area
TOWN HELM ES - Tf R PAGE 9 Or 30
7131/zoo7
Coal Mine_ None located within the one quarter mile area
Critical Drainage Area: The site is not located in any of the King County Critical Drainage Areas
identified in the King County Surface Water Design Manual.
Drainage Problems: None located within the one quarter mile area. (See Figure 3 below).
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Selecta link or search attain_
Parcel 14 rmber. Address 'Assessors Data Report :Districts & Development Reporti'.:
-' .426c53:2 '''. 41-01 TALBQT RD F 6 s
�,einii=--r�C=h® c: ..la: I.l: 4eC .1W
Y i
FiG.3 DRAINAGE COMPLAINTS MAP
Section 4 — Flow Control and Water Quality Facility Analysis and Design
Flow control Analysis and Design
According to Core Requirement #3, the detention vault was designed to Level 2 flow control standard of
downstream protection needs. The drainage on the existing site was analyzed using KCRTS software.
Level 2 flow control requires maintaining the duration of high flows at their predevelopment levels for all
TOWNHOME5 —TIR PAI3F 1 ❑ OF 30
7/2112007
flows greater than one-half of the 2-year peak flow up to the 50-year peak flow. Figures provided in the
KCSWDM and KCRTS manual were used to determine project location and scale factor parameters.
Alderwood gravelly sandy loam (AgC) series, 6 to 15 percent slopes hydrologic class "C".
Existing Site Conditions
The predeveloped condition for matching duration flows was assumed to be historic site condition
(forested).
Total Basin Area: 44,866 S.F. = 1.03 Acres Pervious (Forest)
Land Use Type
?f
Area (acres)
Till Forest 1.03
Till Pasture 0.000
Till Grass 0.000 1
Outwash Forest 0.000
Outwash Pasture 0.000
Outwash Grass 0.000
Wetland 10.000
Impervious 10.000
Scale Factor 1,000
Time Ste
r-` Hourly~ 15-minute
Data Type -
Reduced
Flow Frequency Analysis - Existing Site
Time Series File:existing-7072.tsf
Project Location:Sea-Tac
---Annual
Peak
Flow Rates ---
Flow Rate
Rank
Time of
Peak
(CFS)
0.065
2
2/09/01
18:00
0.018
7
1/06/02
3:00
0.048
4
2/28/03
3:00
0.002
8
3/24/04
21:00
0.029
6
1/05/05
8:00
0.050
3
1/18/06
20:00
0.042
5
11/24/06
4:00
0.083
1
1/09/08
9:00
--------Flow
Frequency
Analysis-------
- Peaks
- - Rank Return
Prob
(CFS)
Period
0.083
1
100.00
0.990
0.065
2
25.00
0.960
0.050
3
10.00
0.900
0.046
4
5.00
0.800
0.042
5
3.00
0.667
0.029
6
2.00
0.500
0.018
7
1.30
0.231
0.002
8
1.10
0.091
TOWMHOMES -- TER PAGE i 1 OF 30
713 1 /2007
Computed Peaks 0.077 50.00 0.980
Developed Site
The developed site drainage system will route runoff to a Level 2 detention pond that will release runoff to
the adjacent property (its natural discharge point), which is tributary to Black River Drainage Basin. This
is where all runoff from the site currently flows.
The following assumptions were used for designing the facility:
For the calculation of impervious area was used the maximum (75% of the project site) impervious
coverage as per city of Renton Municipal Code requirements.
Max_ Impervious Surface for RM-F = 75%
Therefore, Total impervious surface: 44,866 s.f. x 0.75 = 33,650 s_f_ = 0.77 Acres
Pervious (Landscape, Lawn):11,216 s.f. = 0.57 Acres (Use Till Grass)
Total Basin Area: 41,361 s.f. = 1.03 Acres
Land Use Type ?
Area (acresl'
Till Forest 0.000�
Till Pasture
Till Grass
Outwash Forest
Outwash Pasture
Outwash Grass 0.000
Wetland 0.000
Impervious 10.77
Scale Factor 11.000
ToWNHQMES -TIP PAGE 1 2 OF 30
Flow Frequency Analysis - Developed Site
Time Series File:developed-7072.tsf
Project Location:Sea-Tac
---Annual
Peak
Flow Rates ---
Flow Rate
Rank
Time of
Peak
(CFS)
0.210
6
2/09/01
2:00
0.176
8
1/05/02
16:00
0.251
3
2/27/03
7:00
0.197
7
8/26/04
2:00
0.236
4
10/28/04
16:00
0.223
5
1/18/06
16:00
0.286
2
10/26/06
0:00
0.419
1
1/09/08
6:00
Computed Peaks
Retention/Detention Facility
-----Flow
Frequency
Analysis-------
- - Peaks
- - Rank
Return
Prob
(CFS)
Period
0.419
1
100.00
0.990
0.286
2
25.00
0.960
0.251
3
10.00
0.900
0.236
4
5.00
0.800
0.223
5
3.00
0.667
0.210
6
2.00
0.500
0.19"1
7
1.30
0.231
0.176
8
1.10
0.091
0.375
50.00
0.980
Type of Facility:
Detention
Vault
Facility Length:
20.00
ft
Facility width:
76.00
ft
Facility Area:
1.520.
sq. ft
Effective Storage Depth:
10.00
ft
Stage 0 Elevation:
0.00
ft
Storage Volume:
15200.
cu. ft
Riser Head:
10.00
ft
Riser Diameter:
18.00
inches
Number of orifices:
2
Full Head Pipe
Orifice # Height
Diameter
Discharge Diameter
(ft)
(in)
(CFS) (in)
1 0.00
0.50
0.021
2 5.20
0.84
0.042 4.0
Top Notch Weir:
None
Outflow Rating Curve:
None
Stage Elevation
Storage
Discharge
Percolation
(ft) {ft) (cu. ft) (ac-ft)
(cfs)
(cfs)
0.00 0.00
0.
0.000 0.000
0.00
0.01 0.01
15.
0.000 0.001
0.00
0.02 0.02
30.
0.001 0.001
0.00
0.03 0.03
46.
0.001 0.001
0.00
0.04 0.04
61.
0.001 0.001
0.00
0.05 D_05
76.
0.002 0.001
0.00
0.22 0.22
334.
0.008 0.003
0.00
0.39 0.39
593.
0.014 0.004
0.00
0.56 0.56
851.
0.020 0.005
0.00
0.72 0.72
1094.
0.025 0.006
0.00
0.89 0.89
1353.
0.031 0.006
0.00
1.06 1.06
1611.
0.037 0.007
0.00
1.23 1.23
1870.
0.043 0.008
0.00
1.40 1.40
2128.
0.049 0.008
0.00
1.57 1.57
2386.
0.055 0.009
0.00
1.74 1.74
2645.
0.061 0.009
0.00
TOWNHOMES - TIR PAGE 1 3 OF 30
7131/20u7
1.91
1.91
2903.
0.067
0.009
0.00
2.08
2.08
3162.
0.073
0.010
0.00
2.25
2.25
3420.
0.079
0.010
0.00
2.42
2.42
3618,
0.084
0.011
0.00
2.59
2.59
3937.
0.090
0.01.1
0.00
2.76
2.76
4195.
0.096
0.011
0.00
2.93
2.93
4454.
0.102
0.012
0.00
3.10
3.10
4712.
0.108
0.012
0.00
3.27
3.27
4970.
0.114
0.012
0.00
3.44
3.44
5229.
0.120
0.013
0.00
3.61
3.61
5487.
0.126
0.013
0.00
3.78
3.78
5746.
0.132
0.013
0.00
3.95
3.95
6004.
0.138
0.013
0.00
4.11
4.11
6247.
0.143
0.014
0.00
4.28
4.28
6506.
0.149
0.014
0.00
4.45
4.45
6764.
0.155
0.014
0.00
4.62
4.62
7022.
0.161
0.015
0.00
4.79
4.79
1281.
0.167
0.015
0.00
4.96
4.96
1539.
0.173
0.015
0.00
5.13
5.13
7798.
0.179
0.015
0.00
5.20
5.20
1904.
0.181
0.015
0.00
5.21
5.21
7919.
0.182
0.016
0.00
5.22
5.22
'1934.
0.182
0.016
0.00
5.23
5.23
7950.
0.182
0.018
0.00
5.24
5.24
7965.
0.183
0.019
0.00
5.25
5.25
7980.
0.183
0.020
0.00
5.26
5.26
7995.
0.184
0.020
0.00
5.21
5.27
8010.
0.184
0.021
0.00
5.28
5.28
8026.
0.184
0.021
0.00
5.45
5.45
8284.
0.190
0.025
0.00
5.62
5.62
8542.
0.196
0.028
0.00
5.79
5.79
8801.
0.202
0.031
0.00
5.96
5.96
9059.
0.208
0.033
0.00
6.13
6.13
9318.
0.214
0.035
0.00
6.30
6.30
9576_
0.220
0.037
0.00
6.47
6.47
9834.
0.226
0.039
0.00
6.63
6.63
10078.
0.231
0.040
0.00
6.80
6.80
10336.
0.237
0.042
0.00
6.97
6.97
10594,
0.243
0.043
0.00
7.14
7.14
10853.
0.249
0.045
0.00
7.31
7.31
11111.
0.255
0.046
0.00
7.48
7.48
11370,
0.261
0.047
0.00
7.65
7.65
11628,
0.267
0.049
0.00
7.82
7.82
11886.
0.273
0.050
0.00
7.99
7.99
12145.
0.279
0.051
0.00
8.16
8.16
12403.
0.285
0.052
0.00
8.33
8.33
12662.
0.291
0.053
0.00
8.50
8.50
12920.
0.297
0.055
0.00
8.61
8.67
13178.
0.303
0.056
0.00
8.84
8.64
13437.
0.308
0.057
0.00
9.01
9.01
13695.
0.314
0.058
0.00
9.18
9.18
13954.
0.320
0.059
0.00
9.35
9.35
14212.
0.326
0.060
0.00
9.52
9.52
14470.
0.332
0.061
0.00
9.69
9.69
14729.
0.338
0.062
0.00
9.86
9.86
14987.
0.344
0.063
0.00
10.00
10.00
15200.
0.349
0.063
0.00
TOWNHOME5 - TER PAGE 1 4 of 3p
7/3 1 /2007
10.10
10.10
15352.
0.352
0.526
0.00
10.20
10.20
15504.
0.356
1.370
0.00
10.30
10.30
15656.
0.359
2.470
0.00
10.40
10.40
15808.
0.363
3.760
0.00
10.50
10.50
15960.
0.366
3.230
0.00
10.60
10.60
16112.
0.370
6.660
0.00
10.70
10.70
16264.
0.373
7.190
0.00
10.80
10.80
16416.
0.377
7.680
0.00
10.90
10.90
16568.
0.380
8.140
0.00
11.00
11.00
16720.
0.384
8.580
0.00
11.10
11.10
16872.
0.387
8.990
0.00
11.20
11.20
17024.
0.391
9.390
0.00
11.30
11.30
17176.
0.394
9.770
0.00
11.40
11.40
17328.
0.398
10.140
0.00
11.50
11.50
17480.
0.401
10.490
0.00
11.60
11.60
17632.
0.405
10.840
0.00
11.70
11.70
17784.
0.408
11.170
0.00
Hyd
Inflow
Outflow
Peak
Storage
Target
Calc Stage
Elev
(Cu-Ft)
(Ac-Ft)
1
0.42
0.08
0.06 9.78
9.78
14861.
0.341
2
0.21
*******
0.06 8.80
8.80
13371.
0.307
3
0.29
******
0.05 7.78
7.78
11826.
0.271
4
0.22
*******
0.04 6.38
6.38
9692.
0.223
5
0.25
*******
0.05 7.32
7.32
11132.
0.256
6
0.15
0.02 5.35
5.35
8129.
0.187
7
0.18
*******
0.01 4.84
4.84
7350.
0.169
8
0.20
****k**
0.01 3.77
3.77
5729.
0.132
-------------------------------------
Route Time Series through Facility
Inflow Time Series File:developed-7072.tsf
Outflow Time Series File:rdout
Inflow/Outflow Analysis
Peak Inflow Discharge:
Peak Outflow Discharge:
Peak Reservoir Stage:
Peak Reservoir Elev:
Peak Reservoir Storage:
0.419 CFS at 6:00 on Jan 9 in Year 8
0.063 CFS at 14:00 on Jan 9 in Year 8
9.78 Ft
9.78 Ft
14861. Cu-Ft
0.341 Ac-Ft
Flow Duration from Time Series File:rdout.tsf
Cutoff
Count
Frequency
CDF
Exceedence_Probability
CFS
%
%
%
0.001
27375
44.643
44.643
55.357
0.554E+00
0.002
8928
14_560
59.203
40.797
0.408E+00
0.004
5224
8.519
67.722
32.278
0.323E+00
0.006
4047
6.600
74.322
25.678
0.257E+00
0.007
4548
7.417
81.738
18.262
0.183E+00
0.009
3230
5.267
87.006
12.994
0.130E+00
0.010
3338
5.444
92.449
7.551
0.755E-01
0.012
1296
2.114
94.563
5.437
0.544E-01
0.013
1686
2.750
97.312
2.688
0.269E-01
0.015
1268
2.068
99.380
0.620
0.620E-02
0.017
18
0.029
99.410
0.590
0.590E-02
TOWNHOMES - TIR PAGE 1 S OF 20
7131/20Q7
0.018
4
0.007
99.416
0.584
0.584E-02
0.020
9
0.015
99.431
0.569
0.569E-02
0.021
1"7
0.028
99.459
0.541
0.541E-02
0.023
28
0.046
99.504
0.496
0.496E-02
0.024
26
0.042
99.547
0.453
0.453E-02
0.026
24
0.039
99.586
0.414
0.414E-02
0.028
20
0.033
99.618
0.382
0.382E--02
0.029
24
0.039
99.658
0.342
0.342E-02
0.031
18
0.029
99.687
0.313
0.313E-02
0.032
17
0.028
99.715
0.285
0.285E-02
0.034
1.9
0.031
99.746
0.254
0.254E-02
0.035
21
0.034
99.780
0.220
0.220E-02
0.037
21
0.034
99.814
0.186
0.186E-02
0.039
14
0.023
99.837
0.163
0.1.63E-02
0.040
11
0.018
99.855
0.143
0.145E-02
0.042
10
0.016
99.871
0.129
0.129E-02
0.043
12
0.020
99.891
0.109
0.109F-02
0.045
8
0.013
99.904
0.096
0.962E-03
0.046
1.3
0.021
99.925
0.075
0.750E-03
0.048
10
0.016
99.941
0.059
0.587E-03
0.049
11
0.018
99.959
0.041
0.408E-03
0.051
9
0.015
99.974
0.026
0.261E-03
0.053
5
0.008
99.982
0.018
0.179E-03
0.054
2
0.003
99.985
0.015
0.147E-03
0.056
4
0.007
99.992
0.008
0.815E-04
----------------------------------
Flow Frequency Analysis
Time Series File_rdout.tsf
Project Location:Sea-Tau
---Annual
Peak
Flow Rates---
-----Flow
Frequency
Analysis-------
FlowRate
Rank
Time of
Peak
- - Peaks
- -
Rank
Return
Prob
(CFS)
(CFS)
(ft)
Period
0.065
2
2/09/01
20:00
0.073
8.43
1
100.00
0.990
0.016
7
12/29/01
10:00
0.065
7.45
2
25.00
0.960
0.051
4
3/06/03
22:00
0.058
6.69
3
10.00
0.900
0.014
8
8/26/04
7:00
0.051
6.03
4
5.00
0.800
0.025
6
1/05/05
16:00
0.045
5.58
5
3.00
0.667
0.045
5
1/1.8/06
23:00
0.025
4.47
6
2.00
0.500
0.058
3
11/24/06
8:00
0.016
4.00
7
1.30
0.231
0.073
1
1/09/08
12:00
0.014
3.30
8
1.10
0.091
Computed Peaks
0.070
8.15
50.00
0.980
Flow Duration from Time Series File:rdout.tsf
Cutoff
Count
Frequency
CDF
Exceedence
Probability
CFS
s
%
%
0.001
27375
44.643
44.643
55.357
0.554E+00
0.002
8928
14.560
59.203
40.797
0.408E+00
0.004
5224
8.519
67.722
32.278
0.323E+00
0.006
4047
6.600
74.322
25.678
0.257E+00
0.007
4548
7.417
81.738
18.262
0.183E+00
0.009
3230
5.267
87.006
12.994
0.130E+00
0.010
3338
5.444
92.449
7.551
0.755E-01
0.012
1296
2.114
94.563
5.437
0.544E-01
TOWNHOMES - TIR PAGE 16 12F 30
7/31/200 7
0.013
1686
2.750
97.312
2.688
0.269E-01
0.015
1268
2.068
99.380
0.620
0.620E-02
0.017
18
0.029
99.410
0.590
0.590E-02
0.018
4
0.007
99.416
0.584
0.584E-02
0.020
9
0.015
99.431
0.569
0.569E-02
0.021
17
0.028
99.459
0.541
0.541E-02
0.023
28
0.046
99.504
0.496
0.496E-02
0.024
26
0.042
99.547
0.453
0.453E-02
0.026
24
0.039
99.586
0.414
0.414E-02
0.02E
20
0.033
99.618
0.382
0.382E-02
0.029
24
0.039
99.658
0.342
0.392E-02
0.031
18
0.029
99.687
0.313
0.313E-02
0.032
17
0.028
99.715
0.285
0.285E-02
0.034
19
0.031
99.746
0.254
0.254E-02
0.035
21
0.034
99.780
0.220
0.220E-02
0.037
21
0.034
99.819
0.186
0.186E-02
0.039
14
0.023
99.837
0.163
0.163E-02
0.040
11
0.018
99.655
0.145
0.145E-02
0.042
10
0.016
99.871
0.129
0.129E-02
0.043
12
0.020
99.691
0.109
0.109E-02
0.045
8
0.013
99.904
0.096
0.962E--03
0.046
13
0.022
99.925
0.075
0.750E-03
0.048
10
0.016
99.941
0.059
0.587E-03
0.049
11
0.018
99.959
0.041
0.408E--03
0.051
9
0.015
99.974
0.026
0.261E-03
0.053
5
0.008
99.982
0.018
0.179E-03
0.054
2
0.003
99.985
0.015
0.147E-03
0.056
4
0.007
99.992
0.008
0.815E-04
----------------------------------
Duration Comparison Analysis
Base File: existing-7072.tsf
New File: rdout.tsf
Cutoff Units: Discharge in CFS
Cutoff
0.014
0.018
0.022
0.026
0.030
0.034
0.038
0.042
0.045
0.049
0.053
0.057
0.061
0.065
------Fraction of Time-----
BaseNew %Change
0.91E-02 0.17E-01 85.9
0.62E-02 0.58E-02 -5.8
0.48E--02 0.52E-02 6.4
0.37E--02 0.41E-02 13.4
0.28E--02 0.32E-02 1.5.0
0.22E-02 0.25E-02 14.0
0.15E-02 0.17E-02 17.6
0.99E-03 0.13E--02 29.5
0.60E-03 0.90E-03 48.6
0.34E-03 0.42E-03 23.8
0.21E-03 0.16E-03 -23.1
0.16E-03 O.00E+00 -100.0
0.11E-03 0.00E+00 -100.0
0.16E--04 0.00E+00 -100.0
---------Check of Tolerance
Probability Base New
0.91E-02 0.014 0.015
0.62E-02 0.018 0.015
0.48E-02 0.022 0.023
0.37E-02 0.026 0.028
0.28E-02 0.030 0.032
0.22E-02 0.034 0.035
0.15E-02 0.038 0.040
0.99E-03 0.042 0.044
0.60E-03 0.045 0.048
0.34E-03 0.049 0.050
0.21E-03 0.053 0.052
0.16E-03 0.053 0.053
0.11E-03 0.061 0.055
0.16E--04 0.065 0.057
Maximum positive excursion = 0.003 cfs ( 9.5%)
occurring at 0.027 cfs on the Base Data:existing-7072.tsf
and at 0.029 cfs on the New Data:rdout.tsf
Maximum negative excursion = 0.004 cfs (-19.0%)
%Change
3.9
-17.9
4.9
7.9
7.9
4.5
5.5
6.7
5.1
0.5
-1.6
-6.4
-9.6
-12.6
TOWNHOME5 - TIR PAGE 17 of 30
7/31/2pp7
occurring at 0.019 cfs on the Base Data:existing-7072.tsf
and at 0.015 cfs on the New Data:rdout.tsf
Probability Exceedence Graph
� rdprR dw
FarV.dur
n
0
a..
o.
v
r kN
ri
N
P mm
00 3-
O \4.
O �u
_y
I
10 10 — 10 — 10, 10' 10,
Probahiity Eweedg�,e
Required detention vault volume = 15,200 cubic feet
Proposed detention vault volume = [76' L x 20' W x 10' D) x 10% = 16,720 cubic feet
King County recommends - but does not require - a 10% volume correction factor when sizing detention
facilities using KCRTS.
Water Quality Analysis and Design
The basic water quality menu is to be used for this project. The selected BMP is a wet vault.
Facility Sizing Calculations
Runoff — New Developed Condition
• V,= (0.9 Ai+ 0.25 Ar9 + 0.19 Atf + 0.01 A,) x (RI12)
• V, = (0.9 * 33,650 + 0.25 * 11,216) x (0.47/12)
• V, = (30.285 + 2,804) x (0.47l12)
• V, = 1,291 cu.ft
Wetpond Volume
• Vb= f* V,
• Vb=3*1,291
• Vb = 3,871 cu.ft
Required wet vault volume = 3,871 cubic feet
Proposed wet vault volume = 76' L x 20' W x 3' D = 4,560 cubic feet
TOWNHOMES — TIR PAGE 5 6 OF 30
713 1 /2007
Section 5 - Conveyance System Analysis and Design
Backwater Analysis Method from the King County Drainage Manual 2005 was used to analyze the
capacity of the existing pipe systems. This method was used to compute a simple backwater profile
(hydraulic grade line) through the existing pipe system for the purposes of verifying adequate capacity. It
incorporates a re -arranged form of Manning's equation expressed in terms of.frfcteon slope (slope of the
energy grade line in ftlft). The friction slope is used to determine the head loss in each pipe segment due
to barrel friction, which can then be combined with other head losses to obtain water surface elevations at
all structures along the pipe system.
The friction, entrance, and exit head losses computed for each pipe segment were added to that
segment's tailwater elevation to obtain its outlet control headwater elevation. This elevation was then
compared with the inlet control headwater elevation, computed assuming the pipe's inlet alone is
controlling the capacity. The condition that creates the highest headwater elevation determines the pipe's
capacity. The approach velocity was then subtracted from the controlling headwater elevation, and the
junction and bend head losses were added to compute the total headwater elevation, which was then
used as the tail water elevation for the upstream pipe segment.
Backwater Calculation Sheet was used to compile the head losses and headwater elevations for each
pipe segment. (See Appendix C).
Simple backwater profile through the existing pipe system (the adjacent properties to the north, south and
west of our property were analyzed for the purposes of verifying adequate capacity. The entire basin was
divided into sub -basins and using KCRTS software and the flow frequency analysis was performed for
each sub -basin. The maximum 25-year peak flow (Q=0.21cfs) of sub -basin CB2 was used to perform the
backwater analysis. The results of the calculations confirmed that the existing pipe system is adequately
designed to convey the additional flow from the proposed Townhomes system_
Section 6 - Special Reports and Studies
A soils study was completed for this project by Pioneer Engineering, Inc.
Section i - Other Permits
►=
Section 8 - ESC Analysis and Design
I►R7T
Section 9 - Bond Quantities, Facility Summaries, and Declaration of Covenant
None
Section 10 - Operations and Maintenance Manual - See Appendix A
TOWNHOMES - TYR PAGE 1 9 OF 30
7131 /201717
APPENDIX A
TOWNHOMES - TiR RAGE 20 ❑V 30
713 ] /2007
NO.4 - CONTROL STRUCTURE/FLOW RESTRICTOR
Maintenance Defect
Component
Condition When Maintenance is Needed
Results Expected When
Maintenance is Performed
General Trash and Debris
Distance between debris build-up and bottom of
All trash and debris removed.
(Includes Sediment)
orifice plate is less than 1-1/2 feet.
Structural Damage
Structure is not securely attached to manhole wall
Structure securely attached to
and outlet pipe structure should support at least
wall and outlet pipe -
1,000 Ibs of up or down pressure.
Structure is not in upright position (allow up to
Structure in correct position.
10% from plumb).
Connections to outlet pipe are not watertight and
Connections to outlet pipe are
show signs of rust,
water tight; structure repaired or
replaced and works as
designed.
Any holes --other than designed holes --in the
Structure has no holes other
structure.
than designed holes.
Cleanout Gate Damaged or Missing
Cleanout gate is not watertight or is missing.
Gate is watertight and works as
designed_
Gate cannot be moved up and dawn by one
Gate moves up and down easily
maintenance person.
and is watertight.
Chain leading to gate is missing or damaged.
Chain is in place and works as
designed.
Gate is rusted over 50% of its surface area.
Gate is repaired or replaced to
meet design standards..
Orifice Plate Damaged or Missing
Control device is not working properly due to
Plate is in place and works as
missing, out of place, or bent orifice plate.
designed.
Obstructions Any trash, debris, sediment, or vegetation Plate is free of all obstructions
blocking the plate. and works as designed.
Overflow Pipe Obstructions Any trash or debris blocking (or having the Pipe is free of all obstructions
potential of blocking) the overflow pipe. and works as designed.
Manhole See "Closed Detention Systems" Standards No. 3 See "Closed Detention Systems
Standards No. 3
Catch Basin See "Catch Basins" Standards No. 5 See'Catch Basins" Standards
No. 5
TaWNHOME5-TIR RAGF 21 OF 30
7/3 1 /2007
NO.5 - CATCH BASINS
Maintenance Defect Conditions When Maintenance is Needed Results Expected When
Component Maintenance is performed
General Trash & Debris Trash or debris of more than 1/2 cubic foot which is No Trash or debris located
(includes Sediment) located immediately in front of the catch basin immediately in front of catch
opening or is blocking capacity of the basin by basin opening.
more than 10%
Trash or debris (in the basin) that exceeds 1/3 the No trash or debris in the catch
depth from the bottom of basin to invert the lowest basin.
pipe into or out of the basin.
Trash or debris in any inlet or outlet pipe blocking
more than 113 of its height.
Dead animals or vegetation that could generate
odors that could cause complaints or dangerous
gases (e g , methane).
Deposits of garbage exceeding 1 cubic foot in
volume
Structure Damage to Corner of frame extends more than 314 inch past
Frame and/or Top Slab curb face into the street (If applicable).
Top slab has holes larger than 2 square inches or
cracks wider than 1/4 inch (intent is to make sure
all material is running into basin).
Frame not sitting flush on top slab, i.e., separation
of more than 3/4 inch of the frame from the top
slab.
Inlet and outlet pipes free of
trash or debris.
No dead animals or vegetation
present within the catch basin.
No condition present which
would attract or support the
breeding of insects or rodents.
Frame is even with curb.
Top slab is free of holes and
cracks.
Frame is sitting flush on top
slab.
Cracks in Basin Walls/ Cracks wider than 1/2 inch and longer than 3 feet, Basin replaced or repaired to
Bottom any evidence of soil particles entering catch basin design standards.
through cracks, or maintenance person judges that
structure is unsound.
Cracks wider than 1/2 inch and longer than 1 foot No cracks more than 1/4 inch
at the joint of any inlet/ outlet pipe or any evidence wide at the joint of inietloutlet
of soil particles entering catch basin through pipe.
cracks.
Sediment/ Basin has settled more than 1 inch or has rotated
Misalignment more than 2 inches out of alignment.
Basin replaced or repaired to
design standards.
TowNHOME5 - TIR PAGE 22 OF 3❑
7/3 1 /2Op7
NO. a -CATCH BASINS (CONTINUED)
Maintenance Defect Conditions When Maintenance is Needed Results Expected When
Component Maintenance is performed
Fire Hazard Presence of chemicals such as natural gas, oil and
gasoline.
Vegetation Vegetation growing across and blocking more than
10% of the basin opening.
Vegetation growing in inlet/outlet pipe joints that is
more than six inches tall and less than six inches
apart.
Pollution
Catch Basin Cover Cover Not in Place
Ladder
Metal Grates
(If Applicable)
Locking Mechanism
Not Working
Cover Difficult to
Remove
Ladder Rungs
Unsafe
Trash and Debris
Damaged or
Missing.
Nonflammable chemicals of more than 112 cubic foot
per three feet of basin length.
Cover is missing or only partially in place. Any open
catch basin requires maintenance.
Mechanism cannot be opened by on maintenance
person with proper tools. Bolts into frame have less
than 1/2 inch of thread.
One maintenance person cannot remove lid after
applying 80 lbs. of lift; intent is keep cover from
sealing off access to maintenance_
Ladder is unsafe due to missing rungs, misalignment
rust, cracks, or sharp edges.
Grate with opening wider than 718 inch.
Trash and debris that is blocking more than 20% of
grate surface.
Grate missing or broken member(s) of the grate.
No flammable chemicals
present.
No vegetation blocking opening
to basin.
No vegetation or root growth
present.
No pollution present other than
surface film.
Catch basin cover is closed
Mechanism opens with proper
tools.
Cover can be removed by one
maintenance person.
Ladder meets design standards
and allows maintenance person
safe access.
Grate opening meets design
standards.
Grate free of trash and debris.
Grate is in place and meets
design standards.
TOWNHOMr3 - TIR PAGE 23 ❑P' 30
7/3 1 /2007
NO.8 - FENCING
Maintenance Defect Conditions When Maintenance is Needed Results Expected When
Components Maintenance is Performed
General Missing or Broken Any defect in the fence that permits easy entry to Parts in place to provide adequate
Parts a facility. security.
Wire Fences
Erosion
Damaged Parts
Deteriorated Paint or
Protective Coating
Openings in Fabric
Erosion more than 4 inches high and 12-18 No opening under the fence that
inches wide permitting an opening under a exceeds 4 inches in height.
fence.
Post out of plumb more than 6 inches. Post plumb to within 1-1/2 inches.
Top rails bent more than 6 inches. Top rail free of bends greater than
1 inch.
Any part of fence (including post, top rails, and Fence is aligned and meets design
fabric) more than 1 foot out of design alignment. standards.
Missing or loose tension wire Tension wire in place and holding
fabric.
Missing or loose barbed wire that is sagging Barbed wire in place with less than
more than 2-1/2 inches between posts. 314 inch sag between post.
Extension arm missing, broken, or bent out of
shape more than 1 112 inches.
Part or parts that have a rusting or scaling
condition that has affected structural adequacy
Openings in fabric are such that an 8-inch-
diameter ball could fit through
Extension arm in place with no
bends larger than 3/4 inch.
Structurally adequate posts or
parts with a uniform protective
coating.
No openings in fabric.
TOwMHOME5 - TIR pq13-C 24 ❑F 30
7/3 1 /2007
NO.10 - CONVEYANCE SYSTEMS (PIPES & DITCHES)
Maintenance
Defect
Conditions When Maintenance is Needed
Results Expected When
Component
Maintenance is Performed
Pipes
Sediment & Debris
Accumulated sediment that exceeds 20% of the
Pipe cleaned of all sediment and
diameter of the pipe.
debris.
Vegetation
Vegetation that reduces free movement of water
All vegetation removed so wafer
through pipes.
flows freely through pipes.
Damaged
Protective coating is damaged; rust is causing
Pipe repaired or replaced,
more than 50% deterioration to any part of pipe.
Any dent that decreases the cross section area of
Pipe repaired or replaced.
pipe by more than 20%.
Open Ditches
Trash & Debris
Trash and debris exceeds 1 cubic foot per 1,000
Trash and debris cleared from
square feet of ditch and slopes_
ditches.
Sediment
Accumulated sediment that exceeds 20 % of the
Ditch cleaned/ flushed of all
design depth.
sediment and debris so that it
matches design.
Vegetation
Vegetation that reduces free movement of water
Water flows freely through
through ditches.
ditches.
Erosion Damage to
See "Ponds" Standard No. 1
See `Ponds" Standard No. 1
Slopes
Rock Lining Out of Place
Maintenance person can see native soil beneath
Replace rocks to design
or Missing (if
the rock lining.
standards.
Applicable).
Catch Basins
See "Catch Basins: Standard No. 5
See "Catch Basins" Standard
No. 5
Debris Barriers
See "Debris Barriers" Standard No.6
See "Debris Barriers" Standard
(e.g., Trash Rack)
No. 6
NO.11
- GROUNDS (LANDSCAPING)
Maintenance
Defect
Conditions When Maintenance is Needed
Results Expected When
Component
Maintenance is Performed
General
Weeds
Weeds growing in more than 20% of the landscaped
Weeds present in less than 5%
(Nonpoisonous)
area (trees and shrubs only).
of the landscaped area
Safety Hazard
Any presence of poison ivy or other poisonous
No poisonous vegetation
vegetation.
present in landscaped area.
Trash or Litter
Paper, cans, bottles, totaling more than 1 cubic foot
Area clear of litter.
within a landscaped area (trees and shrubs only) of
1,000 square feet.
Trees and Shrubs
Damaged
Limbs or parts of trees or shrubs that are split or
Trees and shrubs with less than
broken which affect more than 25% of the total
5% of total foliage with split or
foliage of the tree or shrub.
broken limbs.
Trees or shrubs that have been blown down or
Tree or shrub in place free of
knocked over.
injury.
Trees or shrubs which are not adequately supported
Tree or shrub in place and
or are leaning over, causing exposure of the roots.
adequately supported; remove
any dead or diseased trees.
TQWNHOMES - TER PAGE 25 OF 30
7/3 1 /2007
NO. 12 - ACCESS ROADS/ EASEMENTS
Maintenance Defect Condition When Maintenance is Needed Results Expected When
Component Maintenance is Performed
General Trash and Debris Trash and debris exceeds 1 cubic foot per 1,000 Roadway free of debris which
square feet i.e., trash and debris would fill up could damage tires.
one standards size garbage can.
Road Surface
Shoulders and
Ditches
Blocked Roadway Debris which could damage vehicle tires (glass Roadway free of debris which
or metal). could damage tires.
Any obstruction which reduces clearance above Roadway overhead clear to 14 feet
road surface to less than 14 feet. high.
Any obstruction restricting the access to a 10 to Obstruction removed to allow at
12 foot width for a distance of more than 12 feet least a 12 foot access.
or any point restricting access to less than a 10
foot width.
Settlement, Potholes, When any surface defect exceeds 6 inches in Road surface uniformly smooth
Mush Spots, Ruts depth and 6 square feet in area. In general, any with no evidence of settlement,
surface defect which hinders or prevents potholes, mush spots, or ruts -
maintenance access.
Vegetation in Road Weeds growing in the road surface that are more Road surface free of weeds taller
Surface than 6 inches tall and less than 6 inches tall and than 2 inches.
Tess than 6 inches apart within a 400-square foot
area.
Modular Grid Build-up of sediment mildly contaminated with
Pavement petroleum hydrocarbons.
Erosion Damage Erosion within 1 foot of the roadway more than 8
inches wide and 6 inches deep.
Weeds and Brush Weeds and brush exceed 18 inches in height or
hinder maintenance access.
Removal of sediment and disposal
in keeping with Health Department
recommendations for mildly
contaminated soils or catch basin
sediments.
Shoulder free of erosion and
matching the surrounding road.
Weeds and brush cut to 2 inches in
height or cleared in such a way as
to allow maintenance access.
TOWNHOMEB -TIR PAGE 26 OF 30
7/3l/2007
NO. 13 -WATER QUALITY FACILITIES (CONTINUED)
E.) Wetvau Its
Maintenance Defect or Problem Condition When Maintenance is Needed Recommended Maintenance to
Component Correct Problem
Wetvault Trash/ Debris Trash and debris accumulated in vault, pipe Remove trash and debris from vault.
Accumulation ❑r inlet/ outlet, (includes floatables and non-
floatables).
Sediment
Sediment accumulation in vault bottom
Accumulation in Vault
exceeds the depth of the sediment zone
plus 6-inches.
Damaged Pipes
Inlet! outlet piping damaged or broken and
in need of repair.
Access Cover
Cover cannot be opened or removed,
Damaged/ Not
especially by one person.
Working
Ventilation Ventilation area blocked or plugged
Vault Structure Vault: Cracks wider than 1/2-inch and any
Damaged evidence of soil particles entering the
structure through the cracks, or
maintenance/ inspection personnel
determines that the vault is not structurally
sound.
Remove sediment from vault.
Pipe repaired andt or replaced.
Pipe repaired or replaced to proper
working specifications.
Remove or clear blocking material from
ventilation area. A specified % of the
vault surface area must provide
ventilation to the vault interior (see p 6-
62 for required %).
Repair cracks wider than 1/4-inch at the
joint of the inlet/ outlet pipe. Make repairs
so that vault is structurally sound.
Baffles Baffles corroding, cracking, warping andl or Repair or replace baffles to
showing signs of failure as determined by specifications.
maintenance/ inspection staff.
Access Ladder Ladder is corroded or deteriorated, not
Damage functioning property, missing rungs, has
cracks and/ or misaligned. Confined space
warning sign missing.
Ladder replaced or repaired to
specifications, and is safe to use as
determined by inspection personnel.
Replace sign warning of confined space
entry requirements.
TowNHOMEB-TIR PAGE 27 ❑F 3❑
7/31/2007
B.) Catch Basin Inserts
Maintenance Defect Conditions When Maintenance is Needed Results Expected When
Component Maintenance is Performed
Catch Basin Sediment When sediment forms a cap over the insert media of No sediment cap on the insert
Accumulation the insert and/ or unit. media and it's unit.
Trash and Debris Trash and debris accumulates on insert unit creating Trash and debris removed from
Accumulation a blockagel restriction. insert unit. Runoff freely flows
into catch basin.
Inspection Inspection of media insert is required. Effluent water from media insert
is free of oils and has no visible
sheen.
Media Insert -Water Catch basin insert is saturated with water, which no Remove and replace media
Saturated longer has the capacity to absorb. insert
Media Insert -Oil Media oil saturated due to petroleum spill that drains Remove and replace media
Saturated into catch basin. insert.
General Regular interval replacement due to typical average Remove and replace media at
life of media insert product. regular intervals, depending on
insert product
TowNHOMEE - TIR PAGE 26 OF 30
7/3 1 /2007
APPENDIX B
TOWNHOMES '-' T1R PAGE 29 ❑F 3❑
7/2 1/2007
APPENDIX C
TOWNHUMES - TFR PAGE 3❑ ❑F 3❑
7/3 1 /2007
Flow Frequency Analysis
Time Series File:cb2'.tsf
Project Location:Sea-Tac
---Annual
Flow Rate
(CFS)
0.033
0.028
0.039
0.031
0.036
0.035
0.044
0.065
computed Peaks
Peak Flaw Rates ---
Rank Time of Peak
6 2/09/01 2:00
8 1/05/02 16:00
3 2/27/03 7:00
7 8/26/04 2:00
4 10/28/04 16:00
5 1/18/06 16:00
2 10/26/06 0:00
1 1/09/08 6:00
-----Flow
Frequency
Analysis -------
- - Peaks
- - Rank Return
Prob
(CFS)
Period
0.065
1
100.00
0.990
0.036
4
5.00
0.800
0.035
5
3.00
0.667
0.033
6
2.00
0.500
0.031
7
1.30
0.231
0.028
8
1.10
0.091
0.058
50.00
0.980
Page 1
Flow Frequency Analysis
Time Series
File:cb3'.tsf
Project
Location:Sea-iac
---Annual
Peak
Flow Rates---
-----Flow
Frequency
Analysis --------
Flow Rate
Rank
Time of Peak
- - Peaks
- - Rank Return
Prob
(CFS)
(CFS)
Period
0.041
6
2/09/01 2:00
0.081
1
100.00
0.990
0.034
8
1105102 1.6:00
0.049
3
12/08/02 18:00
0.038
7
8/26/04 2:00
0.046
4
5.00
0.800
0.046
4
10/28/04 16:00
0.044
5
3.00
0.667
0.044
5
1/18/06 16:00
0.041
6
2.00
0.500
0.056
2
10/26/06 0:00
0.038
7
1.30
0.231
0.081
1
1/09/08 6:00
0.034
8
1.10
0.091
Computed
Peaks
0.073
50.00
0.980
Page 1
Flow Frequency Analysis
Time Series File:cb4'.tsf
Project Location:Sea-Tac
---Annual
Flow Rate
(CFS)
0.041
0.034
0.049
0.038
0.046
0.044
0.056
0.081
Computed Peaks
Peak Flow Rates ---
Rank Time of Peak
6 2/09/01 2:00
8 1/05/02 16:00
3 12/08/02 18:00
7 8/26/04 2:00
4 10128/04 16:00
5 1/18/06 16:00
2 10/26/06 0:00
1 1/09/08 6:00
-----Flow
Frequency
Analysis -------
- - Peaks
- - Rank
Return
Prob
(CFS)
Period
0.081
1
100.00
0.049
3
10.00
0.900
0.046
4
5.00
0.800
0.044
5
3.00
0.667
0.041
6
2.00
0.500
0.038
7
1.30
0.231
0.034
8
1.10
0.091
0.073
50.00
0.980
Page 1
Flaw Frequency Analysis
Time series
File:cb5'.tsf
Project
Location:5ea-Tac
---Annual Peak
Flow Rates ---
Flow Rate Rank
Time of Peak
(CF5)
0.028
6
2/09/01 2:00
0.023
8
1/05/02 16:00
0.033
3
12/08/02 18:00
0.026
7
8/26/04 2:00
0.031
4
10/28/04 16:00
0.030
5
1/18/06 16:00
0.037
2
10/26/06 0:00
0.056
1
1/09/08 6:00
computed
Peaks
Flow Frequency Analysis-
- - Peaks -
- Rank
Return
Prob
(CFs)
Period
0.056
1
100.00
0.990
00
0.900
0.031
4
5.00
0.800
0.030
5
3.00
0.667
0.028
6
2.00
0.500
0.026
7
1.30
0.231
0.023
8
1.10
0.091
0.049
50.00
0.980
Page 1
Flow Frequency Analysis
Time series
File:cb6'.tsf
Project
Location:Sea-Tac
---Annual
Peak
Flow Rates---
-----Flow
Frequency
Analysis -------
Flow Rate
Rank
Time of Peak
- Peaks
- - Rank
Return
Prob
(CFS)
(CF5)
Period
0.028
6
2/09/01 2:00
0.056
1
100.00
0.990
0.023
8
1/05/02 16:00
0.033
3
12/08/02 18:00
0.900
0.026
7
8/26/04 2:00
0.031
4
5.00
0.800
0.031
4
10/28/04 16:00
0.030
5
3.00
0.667
0.030
5
1/18/06 16:00
0.028
6
2.00
0.500
0.037
2
10/26/06 0:00
0.026
7
1.30
0.231
0.056
1
1/09/08 6:00
0.023
8
1.10
❑.091
computed Peaks
0.049
50.00
0.980
Page 1
Flow Frequency Analysi
Time series
File:cb7'.tsf
Project
Location:sea-Tac
---Annual
Peak
Flow Rates ---
Flaw Rate
Rank
Time of Peak
(CFs)
0.118
6
2/09/01 2:00
0.099
8
1/05/02 16:00
0.142
3
2/27/03 7:00
0.110
7
8/26/04 2:00
0.132
4
10/28/04 16:00
0.126
5
1/18/06 16:00
0.160
2
10/26/06 0:00
0.237
1
1/09/08 6:00
computed
Peaks
-----Flow
Frequency
Analysis-------
- - Peaks
- - Rank Return
Prob
(CFs)
Period
7
1
100.00
0.990
0.132
4
5.00
0.800
0.126
5
3.00
0.667
0.118
6
2.00
0.500
0.110
7
1.30
0.231
0.099
8
1.10
0.091
0.211
50.00
0.980
Page 1
Flow Frequency Analysis
Time series
File:cb8'.tsf
Project
Location:Sea-lac
---Annual
Peak
Flow Rates---
-----Flow
Frequency
Analysis -------
Flow Rate
Rank
Time of Peak
- - Peaks
- - Rank
Return
Prob
(CFS)
(CF5)
Period
0.022
6
2/09/01 2:00
0
0.018
8
1/05/02 16:00
0.027
3
2/27/03 7:00
400P0.027
3
10.00
0.900
0.021
7
8/26/04 2:00
0.024
4
5.00
0.800
0.024
4
10/28/04 16:00
0.024
5
3.00
0.667
0.024
5
1/18/06 16:00
0.022
6
2.00
0.500
0.030
2
10/26/06 0:00
0.021
7
1.30
0.231
0.044
1
1/09/08 6:00
0.018
8
1.10
0.091
computed
Peaks
0.039
50.00
0.980
Page 1
Flow Frequency Analysi
Time Series
File:cb9'.tsf
Project
Location:sea-Tac
----Annual Peak
Flow Rates ---
Flow Rate Rank
Time of
Peak
(CF5)
0.022
6
2/09/01
2:00
0.018
8
1./05/02
16:00
0.027
3
2/27/03
7:00
0.021
7
8/26/04
2:00
0.024
4
10/28/04
16:00
0.024
5
1/18/06
16:00
0.030
2
10/26/06
0:00
0.044
1
1/09/08
6:00
Computed
Peaks
Flow Frequency Analysis
- - Peaks -
- Rank
Return
Prob
(CFS)
Period
0.044
1
100.00
0.990
0.027
0.900
0.024
4
5.00
0.800
0.024
5
3.00
0.667
0.022
6
2.00
0.500
0.021
7
1.30
0.231
0.018
8
1.10
0.091
0.039
50.00
0.980
Page 1
Flow Frequency Analysi
Time series
File:cbl0'.tsf
Project
Cocation:Sea-Tac
---Annual
Peak
Flow Rates
---
Flow Rate
Rank
Time of
Peak
(CF5)
0.087
6
2/09/01
2:00
0.073
8
1/05/02
16:00
0.105
3
2127103
7:00
0.082
7
8/26/04
2:00
0.098
4
10/28/04
16:00
0.093
5
1/18/06
16:00
0.119
2
10/26/06
0:00
0.175
1
1/09/08
6:00
computed
Peaks
cb10'.pks
Flow Frequency Analysis
- - Peaks -
- Rank
Return
Prob
(CF5)
Period
0.175
1
100.00
0.00
0.900
0.098
4
5.00
0.800
0.093
5
3.00
0.667
0.087
6
2.00
0.500
0.082
7
1.30
0.231
0.073
8
1.10
0.091
0.156
50.00
0.980
Page 1
Flow Frequency Analysis
Time series
File:cbll'.tsf
Project
Location:5ea-Tac
---Annual
Peak
Flow Rates---
-----Flow
Frequency
Analysis-------
FlowRate
Rank
Time of Peak
- - Peaks
- - Rank Return
Prob
(CFS)
(CF5)
Period
0.060
6
2/09/01 2:00
0.119
1
100.0n
0.050
8
1/05/02 16:00
0.071
3
12/08/02 18:00
U.UII
3
10.00
0.900
0.056
7
8/26/04 2:00
0.067
4
5.00
0.800
0.067
4
10/28/04 16:00
0.064
5
3.00
0.667
0.064
5
1/18/06 16:00
0.060
6
2.00
0.500
0.082
2
10/26/06 0:00
0.056
7
1.30
0.231
0.119
1
1/09/08 6:00
0.050
8
1.10
0.091
Computed
Peaks
0.106
50.00
0.980
Page 1
Flow Frequency Analysis
Time series
File:cbl2'.tsf
Project
Location:Sea-Tac
---Annual
Peak
Flow Rates---
-----Flow
Frequency
Analysis -------
Flow Rate
Rank
Time of
Perak
- - Peaks
- Rank
Return
Prob
(CFS)
(CF5)
Period
0.060
6
2/09/01
2:00
p.11
0.050
8
. 1105102
16:00
0.071
3
12/08/02
18:00
0.071
3
10.00
0.900
0.056
7
8/26/04
2:00
0.067
4
5.00
0.800
0.067
4
10/28/04
16:00
0.064
5
3.00
0.667
0.064
5
1/18/06
16:00
0.060
6
2.00
0.500
0.082
2
10/26/06
0:00
0.056
7
1.30
0.231
0.119
1
1/09/08
6:00
0.050
8
1.10
0.091
computed
Peaks
0.106
50.00
0.980
Page 1
Flow Frequency Analysis
Time series
File:cbl3'.tsf
Project
Location:sea-Tac
---Annual
Peak
Flow Rates
---
Flow Rate
Rank
Time of
Peak
(CF5}
0.090
6
2/09/01
2:00
0.075
8
1/05/02
16:00
0.108
3
2/27/03
7:00
0.084
7
8/26/04
2:00
0.101
4
10/28/04
16:00
0.096
5
1/18/06
16:00
0.123
2
10/26/06
0:00
0.179
1
1/09/08
6:00
computed
Peaks
-----Flow
Frequency
Analysis-------
- - Peaks
- - Rank
Return
Prob
(CF5)
Period
17
1
100.00
0.990
0.108
3
10.00
0.900
0.101
4
5.00
0.800
0.096
5
3.00
0.667
0.090
6
2.00
0.500
0.084
7
1.30
0.231
0.075
8
1.10
0.091
0.160
50.00
0.980
Page 1
Flow Frequency Analysis
Time series
File:cbl4'.tsf
Project
Location:5ea-Tac
---Annual Peak
Flow Rates---
-----Flaw
Frequency
Analysis-------
FlowRate
Rank
Time of
Peak
- - Peaks
- - Rank Return
Prob
(CF5)
(CFS)
Period
0.028
6
2/09/01
2:00
0.056
1
100.00
0.990
0.023
8
1/05/02
16:00
0.033
3
12/08/02
18:00
0.033
1
10.00
0.900
0.026
7
8/26/04
2:00
0.031
4
5.00
0.800
0.031
4
10/28/04
16:00
0.030
5
3.00
0.667
0.030
5
1/18/06
16:00
0.028
6
2.00
0.500
0.037
2
10/26/06
0:00
0.026
7
1.30
0.231
0.056
1
1/09/08
6:00
0.023
8
1.10
0.091
Computed
Peaks
0.049
50.00
0.980
Page 1
Flow Frequency Analysis
Time series
File:cbl5'.tsf
Project
Location:sea-Tac
---Annual
Peak
Flow Rates
---
Flow Rate
Rank
Time of
Peak
(CFs)
0.105
6
2/09/01
2:00
0.089
8
1/05/02
16:00
0.126
3
12/08/02
18:00
0.100
7
8/26/04
2:00
0.119
4
10/28/04
16:00
0.112
5
1/18/06
16:00
0.145
2
10/26/06
0:00
0.210
1
1/09/08
6:00
Computed
Peaks
-----Flow
Frequency
Analysis -------
- - Peaks
- - Rank
Return
Prob
(CFS)
Period
.21Q
26
3
10.00
0.900
0.119
4
5.00
0.800
0.112
5
3.00
0.667
0.105
6
2.00
0.500
0.100
7
1.30
0.231
0.089
8
1.10
0.091
0.188
50.00
0.980
Page 1
Flow Frequency Analysis
Time series File:cbl6'.tsf
Project Location:sea-Tac
---Annual
Flow Rate
(CFS)
0.147
0.124
0.176
0.138
0.165
0.156
0.201
0.293
Computed Peaks
Peak Flow Rates ---
Rank Time of Peak
6 2/09/01 2:00
8 1/05/02 16:00
3 2/27/03 7:00
7 8/26/04 2:00
4 10/28/04 16:00
5 1/18/06 16:00
2 10/26/06 0:00
1 1/09/08 6:00
cb16'.Pks
Flow Frequency Analysis
- - Peaks -
- Rank
Return
Prob
(CFS)
Period
0.293
1
100.00
0.990
0.176
3
10.00
0.900
0.165
4
5.00
0.800
0.156
5
3.00
0.667
0.147
6
2.00
0.500
0.138
7
1.30
0.231
0.124
8
1.10
0.091
0.263
50.00
0.980
Page 1
Cb17'.pk5
Flow Frequency Analysis
Time series
File:cbl7'.tsf
Project
Location:Sea-Tac
--Annual
Peak
Flow Rates---
-----Flow Frequency
Analysis-------
FlowRate
Rank
Time of
Peak
- - Peaks -
- Rank
Return
Prob
(CFS)
(CFs)
Period
0.028
6
2/09/01
2:00
0.056
I
inn nn
n QQA
0.023
8
1105102
16:00
0.033
3
12/08/02
18:00
033
3
10.00
0.90
0.026
7
8/26/04
2:00
0.031
4
5.00
0.800
0.031
4
10/28/04
16:00
0.030
5
3.00
0.667
0.030
5
1/18/06
16:00
0.028
6
2.00
0.500
0.037
2
10/26/06
0:00
0.026
7
1.30
0.231
0.056
1
1/09/08
6:00
0.023
8
1.10
0.091
computed
Peaks
0.049
50.00
0.980
Page 1
Plow Frequency Analysi
Time Series
File:cbl8'.tsf
Project
Location:Sea-Tac
---Annual
Peak
Flow Rates ---
Flow Rate
Rank
Time of Peak
(CFS)
0.033
6
2/09/01 2:00
0.028
8
1105102 16:00
0.039
3
2/27/03 7:00
0.031
7
8/26/04 2:00
0.036
4
10/28/04 16:00
0.035
5
1/18/06 16:00
0.044
2
10/26/06 0:00
0.065
1
1/09/08 6:00
Computed
Peaks
cb18'.pks
-----Flow
Frequency
Analysis-------
- - Peaks
- - Rank
Return
Prob
(CFS)
Period
0.065
1
100.00
0.990
0.039
3
10.00
0.900
0.036
4
5.00
0.800
0.035
5
3.00
0.667
0.033
6
2.00
0.500
0.031
7
1.30
0.231
0.028
8
1.10
0.091
0.058
50.00
0.980
Page 1
cbl.pks
Flow Frequency Analysis
Time series
File:cbl.tsf
Project
Location:Sea-Tac
---annual
Peak
Flow Rates---
-----Flow
Frequency
Analysis-------
FlowRate
Rank
Time of
Peak
- - Peaks
- - Rank
Return
Prob
(CFS)
(CFS)
Period
0.029
6
2/09/01
2:00
0.059
1
100.00
0.990
0.025
8
1105102
16:00
0.041
2
25.00
0.960
0.035
3
12/08/02
18:00
0.035
3
10.00
0.900
0.028
7
8/26/04
2:00
0.034
4
5.00
0.80C
0.034
4
10/28/04
16:00
0.031
5
3.00
0.667
0.031
5
1/18/06
16:00
0.029
6
2.00
0.500
0.041
2
10/26/06
0:00
0.028
7
1.30
0.231
0.059
1
1/09/08
6:00
0.025
8
1.10
0.091
computed
Peaks
0.053
50.00
0.980
Page 1
Flow Frequency Analysis
Time series
File:cb2.tsf
Project
Location:Sea-Tac
---Annual
Peak
Flow Rates
---
Flow Rate
Rank
Time of
Peak
(CF5)
0.155
6
2/09/01
2:00
0.130
8
1105102
16:00
0.186
3
2127103
7:00
0.146
7
8/26/04
2:00
0.174
4
10/28/04
16:00
0.165
5
1/18/06
16:00
0.212
2
10/26/06
0:00
0.309
1
1/09/08
6:00
Computed
Peaks
cb2.pks
-----Flow
Frequency
Analysis-------
- - Peaks
- - Rank Return
Prob
(CF5)
Period
0.309
1
100.00
0.990
0.212
2
25.00
0.960
0.186
3
10.00
0.900
0.174
4
5.00
0.800
0.165
5
3.00
0.667
0.155
6
2.00
0.500
0.146
7
1.30
0.231
0.130
8
1.10
0.091
0.277
50.00
0.980
Page 1
cb3.pks
Flow Frequency Analysis
Time series
File:cb3.tsf
Project
Lacation:sea-Tac
---Annual
Peak
Flow Rates---
-----Flow
Frequency
Analysis-------
FlowRate
Rank
Time of
Peak
- - Peaks
- - Rank Return
Prob
(CPS)
(CFS)
Period
0.014
4
2/09/01
2:00
0.031
1
100.00
0.990
0.010
7
1/05/02
16:00
0.018
2
25.00
0.960
0.018
2
2/27/03
7:00
0.015
3
10.00
0.900
0.009
8
8/26/04
2:00
0.014
4
5.00
0.800
0.011
6
10/28/04
16:00
0.014
5
3.00
0.667
0.015
3
1/18/06
16:00
0.011
6
2.00
0.500
0.014
5
11/24/06
3:00
0.010
7
1.30
0.231
0.031
1
1/09/08
6:00
0.009
8
1.10
0.091
Computed
Peaks
0.027
50.00
0.980
Page 1
cb4.pks
Flow Frequency Analysis
Time Series
File:cb4.tsf
Project
Location:sea-Tat
---Annual
Peak
Flow Rates---
-----Flow
Frequency
Analysis-------
FlowRate
Rank
Time of Peak
- - Peaks
- - Rank
Return
Prob
(CF5)
(CFS)
Period
0.125
6
2/09/01 2:00
0.249
1
100.00
0.990
0.105
8
1/05/02 16:00
0.171
2
25.00
0.960
0.150
3
2/27/03 7:00
0.150
3
10.00
0.900
0.117
7
8/26/04 2:00
0.140
4
5.00
0.800
0.140
4
10/28/04 16:00
0.133
5
3.00
0.667
0.133
5
1/18/06 16:00
0.125
6
2.00
0.500
0.171
2
10/26/06 0:00
0.117
7
1.30
0.231
0.249
1
1/09/08 6:00
0.105
8
1.10
0.091
Computed
Peaks
0.223
50.00
0.980
Page 1
cb5.pks
Flow Frequency Analysis
Time series
File:cb5.tsf
Project
Location:sea-Tac
---Annual
Peak
Flow Rates---
-----Flow
Frequency
Analysis-------
FlowRate
Rank
Time of Peak
- - Peaks
- - Rank
Return
Prob
(CFS)
(CFS)
Period
0.090
6
2/09/01 2:00
0.179
1
100.00
0.990
0.075
8
1/05/02 16:00
0.123
2
25.00
0.960
0.108
3
2/27/03 7:00
0.108
3
10.00
0.900
0.084
7
8/26/04 2:00
0.101
4
5.00
0.800
0.101
4
10/28/04 16:00
0.096
5
3.00
0.667
0.096
5
1/18/06 16:00
0.090
6
2.00
0.500
0.123
2
10/26/06 0:00
0.084
7
1.30
0.231
0.179
1
1/09/08 6:00
0.075
8
1.10
0.091
computed
Peaks
0.160
50.00
0.980
Page 1
cb6.pks
Flow Frequency Analysis
Time series
File:cb6.tsf
Project
LOcation:sea-Tac
---Annual
Peak
Flow Rates---
-----Flow
Flow Rate
Rank
Time of
Peak
- - Peaks
(CF5)
(CFS)
0.098
6
2/09/01
2:00
0.195
0.083
8
1/05/02
16:00
0.134
0.117
3
2/27/03
7:00
0.117
0.092
7
8/26/04
2:00
0.110
0.110
4
10/28/04
16:00
0.104
0.104
5
1/18/06
16:00
0.098
0.134
2
10/26/06
0:00
0.092
0.195
1
1/09/08
6:00
0.083
computed
Peaks
0.175
Page 1
Frequency Analysis------
- - Rank Return Prob
Period
�I�IraiI� � � •
2
25.00
0.960
3
10.00
0.900
4
5.00
0.800
5
3.00
0.667
6
2.00
0.500
7
1.30
0.231
8
1.10
0.091
50.00
0.980
08. pks
Flow Frequency Analysis
Time series
File:cb8.tsf
Project
Location:5ea-Tac
---Annual
Peak
Flow Rates---
-----Flow
Frequency
Analysis-------
FlowRate
Rank
Time of
Peak
- - Peaks
- - Rank Return
Prob
(CFS)
(CF5)
Period
0.029
6
2/09/01
2:00
0.059
1
100.00
0.990
0.025
8
1/05/02
16:00
0.041
2
25.00
0.960
0.035
3
12/08/02
18:00
0.035
3
10.00
0.900
0.028
7
8/26/04
2:00
0.034
4
5.00
0.$00
0.034
4
10/28/04
16:00
0.031
5
3.00
0.667
0.031
5
1/18/06
16:00
0.029
6
2.00
0.500
0.041
2
10/26/06
0:00
0.028
7
1.30
0.231
0.059
1
1/09/08
6:00
0.025
8
1.10
0.091
Computed
Peaks
0.053
50.00
0.980
Page 1
cbll.pks
Flow Frequency Analysis
Time Series
File:cbll.tsf
Project
Location:5ea-Tac
---Annual
Peak
Flow Rates---
-----Flow
Frequency
Analysis-------
FlowRate
Rank
Time of
Peak
- - Peaks
- - Rank Return
Prob
(CFS)
(CFS)
Period
0.062
6
2/09/01
2:00
0.124
1
100.00
0.990
0.052
8
1/05/02
16:00
0.085
2
25.00
0.960
0.074
3
12/08/02
18:00
0.074
3
10.00
0.900
0.059
7
8/26/04
2:00
0.070
4
5.00
0.800
0.070
4
10/28/04
16:00
0.066
5
3.00
0.667
0.066
5
1/18/06
16:00
0.062
6
2.00
0.500
0.085
2
10/26/06
0:00
0.059
7
1.30
0.231
0.124
1
1/09/08
6:00
0.052
8
1.10
0.091
Computed
Peaks
0.111
50.00
0.980
Page 1
cbl2.pks
Flow Frequency Analysis
Time series
File:cbl2.tsf
Project
Location:5ea-Tac
---Annual
Peak
Flow Rates---
-----Flow
Frequency
Analysis-------
FlowRate
Rank
Time of Peak
- - Peaks
- - Rank Return
Prob
(CFS)
(CF5)
Period
0.041
6
2/09/01 2:00
0.081
1
100.00
0.990
0.034
8
1/05/02 16:00
0.056
2
25.00
0.960
0.049
3
12/08/02 18:00
0.049
3
10.00
0.900
0.038
7
8/26/04 2:00
0.046
4
5.00
0.800
M46
4
10/28/04 16:00
0.044
5
3.00
0.667
0.044
5
1/18/06 16:00
0.041
6
2.00
0.500
0.056
2
10/26/06 0:00
0.038
7
1.30
0.231
M81
1
1/09/08 6:00
0.034
8
1.10
0.091
computed
Peaks
0.073
50.00
0.980
Page 1
cbl3.pks
Flow Frequency Analysis
Time series
File:cbl3.tsf
Project
Location:5ea-Tac
---Annual
peak
Flow Rates---
-----Flow
Frequency
Analysis -------
Flow Rate
Rank
Time of Peak
- - Peaks
- - Rank
Return
Prob
(CFS)
(cFs)
Period
0.024
6
2/09/01 2:00
0.049
1
100.00
0.990
0.021
8
1/05/02 16:00
0.033
2
25.00
0.960
0.029
3
2127103 7:00
0.029
3
10.00
0.900
0.023
7
8/26/04 2:00
0.028
4
5.00
0.800
0.028
4
10/28/04 16:00
0.026
5
3.00
0.667
0.026
5
1/18/06 16:00
0.024
6
2.00
0.500
0.033
2
10/26/06 0:00
0.023
7
1.30
0.231
0.049
1
1/09/08 6:00
0.021
8
1.10
0.091
computed Peaks
0.044
50.00
0.980
Page 1
cbl4.pks
Flow Frequency Analysis
Time series
File:cbl4.tsf
Project
Location:Sea-Tac
--Annual
Peak
Flow Rates---
-----Flow
Frequency
Analysis-------
FlowRate
Rank
Time of Peak
- - Peaks
- - Rank Return
Prob
(cFS)
(CFS)
Period
0.087
6
2/09/01 2:00
0.175
1
100.00
0.990
0.073
8
1/05/02 16:00
0.119
2
25.00
0.960
0.105
3
2127103 7:00
0.105
3
10.00
0.900
0.082
7
8/26/04 2:00
0.098
4
5.00
0.800
0.098
4
10/28/04 16:00
0.093
5
3.00
0.667
0.093
5
1/18/06 16:00
0.087
6
2.00
0.500
0.119
2
10/26/06 0:00
0.082
7
1.30
0.231
0.175
1
1/09/08 6:00
0.073
8
1.10
0.091
computed
Peaks
0.156
50.00
0.980
Page 1
cbl5,pks
Flow frequency Analysis
Time Series
File:eb15.tsf
Project
Location:5ea-Tac
--Annual
Peak
Flow Rates---
-----Flow
Frequency
Analysis -------
Flow Rate
Rank
Time of
Peak
- - Peaks
- - Rank
Return
Prob
(CF5)
(CF5)
Period
0.098
6
2/09/01
2:00
0.195
1
100.00
0.990
0.083
8
1/05/02
16:00
0.134
2
25.00
0.960
0.117
3
2/27/03
7:00
0.117
3
10.00
0.900
0.092
7
8/26/04
2:00
0.110
4
5.00
0.800
0.110
4
10/28/04
16:00
0.104
5
3.00
0.667
0.104
5
1/18/06
16:00
0.098
6
2.00
0.500
0.134
2
10/26/06
0:00
0.092
7
1.30
0.231
0.195
1
1/09/08
6:00
0.083
8
1.10
0.091
Computed
Peaks
0.175
50.00
0.980
Page 1
Pipe
Segment
CB to CB
1
2
13
14
15
14
2
3
3
4
5
5
6
7
8
9
10
11
8
11
16
11
12
13
14
4
1
1
1
2
3
4
4
5
2
13
14
15
16
17
-3
18
4
5
19
6
7
8
9
10
11
12
11
16
NEW
12
13
14
15
1
7
8
2
3
4
9
5
6
KC-BackwaterAnalysis,xls
Page 1
(1) (2) (3) (4) (5) {6) (7) (8) (9) (10) (11) (12) (13) (14) (15) (16) (17) (18) (19) (20)
Barrel Enfr. Entr. Exit Outlet Inlet Appr. Bend Junc.
Pipe Outlet Inlet Barrel Barrel Vel. TW Friction HGL Head Head Control Conrol Vel. Head Head HW Ground
Q Length Size "`n'" Elev. Elev. Area Velocity Head Elev. Loss Elev. Loss Loss Elev. Elev. Head Loss Loss Elev. Elev. Diff.
(cfs) A (in) Value (ft) (ft) (sq ft) (fps) (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft)
0.21
88
18
0.012
87,31
89.51
1.77
0.12
O.OD
88.68
0 00
91.01
0.00
0.00
91.01
90.56 1
0.00
0.00
0.00
91.01
99.50
8.49
0.21
180
12
0.012
90.01
105.20
0.79
0.27
0.00
91.01
0.01
106.20
0.00
0.00
106.20
105.83
0.00
0.00
0.00
106.20
109.10
2.90
0.21
170
12
0.012
105.30
113.57
0.79
0.27
0.00
106.20
0.00
114.57
0.00
0.00
114.57
11422
0.00
0.00
0.00
114.57
117.80
3.23
0.21
150
12
0.012
113.67
119.27
0.79
D.27
0.00
114.57
0.00
120.27
O.DO
0.00
120.27
119.92
-0.01
0.00
0.00
120.26
123.50
3.24
0.21
125
8
0.012
119.60
129.50
0.35
0.60
0.01
120.26
0.03
130.17
0.00
0.01
130.18
129.93
-0.01
0.00
0.00
130.17
133-50
3.33
0.21
54
8
0.012
113.90
114.98
0.35
0.60
0.01
114.57
0.01
115.65
0.00
0.01
115.66
115.43
0.00
TOO
0.00
115.65
118.00
2.35
0.21
130
18
0.012
89.61
92.21
1.77
0.12
0.00
91.01
O.00
93.71
0.00
0.00
93.71
93.20
-0.01
0.00
0.00
93.70
101.60
7.90
0.21
68
8
0.012
92,46
96.50
0.35
0.60
OA1
93.70
0.02
97.17
0.00
0.01
97.18
96.94
0.00
0.00
0.00
97.17
104.00
6.83
0.21
145
15
0.012
92A6
95.36
1,23
0.17
0.00
93.70
0.00
96.61
0.00
0.00
96.61
96.19
0.00
0.00
0.00
96.61
102.00
5.39
0.21
184
12
0.012
95.61
103.71
0.79
0.27
O.OD
96.61
0.01
104.71
0.00
0.00
104.71
104.36
-0.01
0.00
0,00
104.71
107.70
2.99
0.21
73
8
0.012
103.81
108.00
0.35
0.60
0.01
104.71
0.02
108.67
0.00
0.01
108,68
108.44
0,00
0.00
O.OD
108.67
112.00
3,33
0.21
110
18
0.012
103.81
111.20
1.77
0.12
0.00
104.71
0.00
112,70
0.00
0,00
112.70
112.16
0.00
0.00
0.00
112.70
115.00
2.30
0,21
40
12
O.D12
111.30
114.00
0.79
0.27
0.00
112.70
0.00
115.00
0.00
0.00
115.00
114.64
0.00
0.00
0.00
115.00
118.00
3.00
0.21
170
18
0.012
114.10
122.20
1.77
0.12
0.00
115.00
O.DO
123.70
0.00
0.00
123.70
123.17
0.00
0.00
0.00
123.70
126.00
2.30
0.21
45
12
0.012
122.30
123.42
0.79
0.27
0.00
123.70
O.OD
124.42
0.00
0.00
124.42
124.08
0.00
0.00
0.00
124.42
127.50
3.08
0.21
115
12
0.012
123.52
130.99
0.79
0.27
0.00
124.42
0.00
131.99
0.00
0.00
131.99
131.63
0.00
0.00
0.00
131.99
135.00
3.01
0.21
130
12
0.012
131.09
141.77
0.79
0.27
0.00
131.99
0.00
142.77
0.00
0.00
142.77
142.40
-0.01
0.00
0,00
142.76
146.00
3.24
0.21
45
1 8
0.012
1 142.10
142.55
0.35
0.60
0.01
142.76
0.01
143.22
0.00
0.01
143.23
143.01
0.00
0.00
0.00
143.23
1 145.00
1.77
0.21
47
12
0.012
123.37
123.84
0.79
0.27
0.00
123.70
0.00
124.84
0.00
0.00
124.84
124.51
0.00
0.00
0.00
124.84
127.00
2.16
0.21
50
12
0.012
123.84
126.69
0.79
0.27
0.00
124.84
0.00
127.69
0.00
0.00
127.69
127.33
0.00
0.00
0,00
127.69
130.10
2.41
0.21
65
12
0.012
126.69
130.59
0.79
0.27
0.00
127.69
0.00
131.59
0.00
0.00
131.59
131.23
0.00
0.00
0-00
131.59
132.00
0.41
0.21
116
12
0.012
123.84
125.00
0.79
0.27
0.00
124.84
0.00
126.DD
OM
0.00
126.00
125.67
0.00
0.00
0.00
126.00
128.90
2.90
a21
108
12
0.012
125.00
127.16
0.79
0.27
0.00
126.00
0.00
128-15
0.00
0.00
128.16
127.82
0.00
0.00
0.00
128.16
130.60
2.44
0.21
72
12
0.012
1 127.16
129.46
0.79
0.27
0.00
128.16
0.00
130.46
0.00
0.00
130.46
130.12
0.00
0.00
0.00
130.46
132.90
2.44
0.21
170
12
0.012
1 129.46
141.06
0.79
0.27
MO
130.46
0.00
142.06
0.00
0.00
142.06
141.70
0.00
0.00
0.00
142.06
144.50
2.44
0.21
84
12
0.012
95.73
96.57
0.79
0.27
0.00
96.61
0-00
97.57
0.00
0.00
97.57
97.24
-0.01
0.00
0.00
97.57
102.60
5.03
0.21
58
8
0.012
96.57
97.48
0.35
0.60
0.01
97.57
0.01
98.15
0.00
0.01
98.16
97.94
0.00
0.00
0-00
98.15
99.20
1.05
0.21
133
12
0 012
96.57
97.23
0.79
0.27
0.00
97.57
0.00
98.23
0.00
0.00
98.23
97.90
0.00
0-00
0.00
98.23
99.00
0.77
0.21
72
12
0.012
96.57
97.29
0.79
0.27
0,00
97.57
0.00
98.29
0.00
0.00
98.29
97,96
0.00
0.00
0.00
98.29
100.00
1.71
0.21
162
12
0.012
97.29
101.50
1 0.79
0.27
0.00
98.29
0.00
102.50
0.00
0.00
102.50
102.16
0.00
0.00
0.00
102.50
104.80
2.30
0.21
200
12
0.012
101.50
108.70
0.79
0.27
0.00
102.50
0.01
109.70
0.00
0.00
109.70
109.35
-0.01
-0.01
0.00
109.69
115.50
5.81
0.21
57
8
0.012
109.03
116.10
0.35
0,60
0.01
109.69
0.01
116,77
0.00
0.01
116.78
116.52
0.00
0.00
0.00
116.77
119.10
2.33
0.21
90
12
0.012
108.70
109.60
0.79
0.27
0.00
109.69
D-00
110.60
0.00
0.00
110.60
11027
0.01
0.01
0.00
110.59
113.00
2.41
0.21
116
8
0.012
109.93
111.10
0.35
1 0.60
0.01
110.59
0.03
111.77
0.00
0.01
111.78
0.00
0.00
0.00
0.00
111.78
114.50
2,72
PACurrent Projects17072 Y&L Renton Townhomes\Documents\}{C-BackwaterAnalysis,xls6126/2007
KC-BackwatelrAnaiysis.xis
D. ft
P
R=AIP
Ke
Kb
N
c
Y
slope
HWID
HW
inlet or outlet
pipe surch.
1.50
4.71
0.38
0.5
0.08
0
0.0398
0.67
0.0250
066
0.99
91.01
outlet
-7.27
yes
1.00
3.14
0.25
0.5
0.06
0
0.0398
0.67
0.0844
0.63
0.63
106.20
outlet
0.00
yes
1.00
3.14
0.25
0.5
0.02
0
0.0398
0.67
0.0486
0.65
0.65
114.57
outlet
0.00
yes
1.00
3.14
0.25
0.5
0.30
0
0.0398
0.67
0.0373
0.65
0.65
120.27
outlet
0.01
no
0.67
2.09
0.17
0.5
0.28
0
0.0398
0.67
0.0792
065
043
130.18
outlet
0.00
yes
0.67
2.09
0.17
0.5
0.48
0
0.0398
0.67
0.0200
0.68
0.45
115.66
outlet
-0.01
yes
1.50
4.71
0.38
0.5
0.02
0
0.0398
0.67
0.0200
0.66
0.99
93.71
outlet
0.0i
no
0.67
2.09
0.17
0.5
0.64
0
00398
0.67
0.0594
0.66
0.44
97.18
outlet
-0.01
yes
1.25
3.93
0.31
0.5
1.40
0
0.0398
0.67
0.0200
0.66
0.83
96.61
outlet
0.00
no
1.00
114
025
05
0.02
0
0.0398
0.67
0.0440
0.65
0.65
104.71
outlet
0.00
no
0.67
2.09
0.17
0.5
0.40
0
0.0398
0.67
0.0574
0.66
0.44
108.68
outlet
-0.01
yes
1.50
4.71
0.38
0.5
0.01
0
0.0398
0.67
0.0672
0.64
0.96
112.70
outlet
0.00
no
1.00
3.14
0.25
05
001
0
0.0398
0.67
00675
MAI
0.64
115.00
outlet
0.00
yes
1.50
4.71
0.38
0.5
0.60
0
0.0398
0.67
0.0476
0.65
0.97
123.70
outlet
0.00
no
1.00
3.14
0.25
0.5
0.32
0
0.0398
0.67
0.0249
0.66
0.66
124.42
outlet
0.00
yes
1.00
3.14
0.25
05
0.40
0
0.0398
0.67
0.0650
0.64
0.64
131.99
outlet
0.00
yes
1.00
314
0.25
0.5
0.60
0
0.0398
0.67
0.0822
0.63
0.63
142.77
outlet
0.01
no
0.67
2.09
0.17
0.5
0.38
0
0.0398
0.67
0.0100
0.69
0.46
143.23
outlet
-0.01
yes
1.00
3.14
025
0-5
0.01
0
0.0398
0.67
0.0100
0.67
0.67
124.84
outlet
OM
yes
1.00
3.14
0.25
0.5
0.80
0
0.0398
0.67
0.0570
0.64
0.64
127.69
outlet
0.00
no
1.00
3.14
0.25
0.5
0.01
0
0.0398
0.67
0.0600
0.64
0.64
131.59
outlet
0.00
yes
1.00
3.14
0.25
0.5
0.01
0
0.0398
0.67
0.0100
0.67
0.67
126.00
outlet
0.00
yes
1.00
3.14
0.25
0.5
0.01
0
0.0398
0.67
0.0200
066
0.66
128A6
outlet
0.00
yes
1.00
3.14
025
0.5
040
0
0.0398
0.67
0.0319
0.66
0.66
130.46
outlet
0.00
yes
1.00
3.14
0.25
0.5
0.30
0
0.0398
0.67
0.0682
0.64
0.64
142.06
outlet
0.00
yes
1.00
3.14
0.25
0.5
0.01
0
0.0398
0.67
0.0100
0.67
0.67
97.57
outlet
0.00
no
0.67
2.09
0.17
0.5
0.80
0
0.0398
0.67
0.0157
0.68
0.46
98.16
outlet
-0.01
yes
1.00
3.14
0.25
0.5
0.68
0
0.0398
0.67
0.0050
0.67
0.67
98.23
outlet
0.00
no
1.00
3.14
0.25
0.5
0.01
0
0.0398
0.67
0.0100
0.67
0.67
98.29
outlet
0.00
yes
1.00
3.14
0.25
05
1.00
0
0.0398
0.67
0.0260
0.66
0.66
102.50
outlet
0.00
no
1.00
3.14
0.25
0.5
1.30
0
0.0398
0.67
0.0360
0.65
0.65
109.70
outlet
0.01
no
0.67
2.09
0.17
0.5
0.20
0
0.0398
0.67
0.1240
0.63
0.42
116.78
outlet
-0.01
yes
1.00
3.14
0.25
0.5
1.30
0
0.0398
0.67
0.0100
0.67
067
110.60
outlet
0.01
no
0.67
2.09
017
0.5
1.20
0
0.0398
0.67
0.0100
0.69
0.46
111.78
outlet
-0.01
yes
Page 2
P_1Current Projects\7072 Y&L Renton Town homes\Documents\KC-BackwaterAnalysis.xls6/26/2007