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Laureen M. Nicolay From: Sent: To: Cc: Subject: • Stacy Tucker Wednesday, March 19, 2014 2:47 PM Jennifer T. Henning; Laureen M. Nicolay Neil R. Watts RE: LUAll-053 Larson Parke Bonds? This is a Joe Singh project and his company went out of business . .9~·1y~ Administrative Secretary City of Renton CED I Planning Division 1055 S Grady Way I 6th Floor I Renton, WA 98057 Phone: 425.430.7282 I Fax: 425.430.7300 I stucker@rentonwa.gov ~ Please consider the environment before printing this email From: Jennifer T. Henning Sent: Wednesday, March 19, 2014 2:31 PM To: Stacy Tucker; Laureen M, Nicolay Cc: Neil R, Watts Subject: RE: LUAll-053 Larson Parke Bonds? • We can notify the o_wner that we cannot release the bonds until these improvements are constructed. Stacy, is there contact info on the bonds, so I can write a letter?- ------····-.. ··----··----··· .. ---·---......... --- From: Stacy Tucker Sent: Wednesday, March 19, 2014 1:52 PM To: Laureen M. Nicolay Cc: Neil R, Watts; Jennifer T. Henning Subject: RE: LUAll-053 Larson Parke Bonds? We still have 2 maintenance bonds for this project: $67,100: maintenance/defect surety bond for roads and drainage facilities $14,959: landscape install & maintenance surety bond .9~..LY~ Administrative Secretary City of Renton CED I Planning Division I 1055 S Grady Way I 6th Floor I Renton,.057 Phone: 425.430.7282 I Fax: 425.430.7300 I stucker@rentonwa.gov ~ rf1''.r;:oi. "ID; , ·r·l ~·;~\ ... ,_______. . r.t' ;.:,.>I 't• !J I · '"W -~:_-·,.;.;J, '" ,.....,,..., "'~>' ~ Please consider the environment before printing this email From: Debra Mikolaizik Sent: Wednesday, March 19, 2014 11:34 AM To: Stacy Tucker Cc: Laureen M. Nicolay Subject: FW: LUAll-053 Larson Parke Bonds? Stacy is doing this portion of Carrie's job . • .................... ---·-----~--------------·----·--·------.................................... __ ,. _______ _ From: Laureen M. Nicolay Sent: Wednesday, March 19, 2014 11:12 AM To: Debra Mikolaizik Subject: LUAll-053 Larson Parke Bonds? Hi Debra, C • r, Do we have any sureties remaining for this project please? The homeowners never got their recreation tract playground equipment installed per King County plat requirements and are wondering if we have any surety money remaining for this one. Thank you, Laureen ,t<UI/Zee# 1Ueofa9, Senior Planner Department of Community and Economic Development 425-430-7294 2 ::,· ....... DAT[o_g'[~2L ____________ _ S•GNA n.JR[ Of" d:2.1t__.,....,, •. \ NOTARY PUB~1;:::.+~~------ ... y APPOINTMENT [XP1RES.:'.7.::.~:::~--,:··· PAlNTEO N"""E OF '.' NOT .. RY Pua~,c~_E. ... ~- ST .. T( OF w .. SHoNGION COUNTY Of" _lfil'I_G __ ss. PA.Ul,.·.J, •... ~ORROW· ; ..... -~TAT( Of IAffl!teTOlt' : '.xo,fM't--l'OOt.1c ll'J~E»'lllfS1·15:·r• .•. J00?-0\lcr:D\}~ 1 CElrnFY lHAT I KNOW OR HAVE SATisf'ACIOA~:EVIDENC('··.rnAT -~1,if. FONG SICN[O THIS '.:c~Kr:~:~Gt~t.~:~ T~~"~w~~:.fo5:eE~~~t~ir ~=~:g~t[~;J~~~t:~~~~ 1 T~"~E THE rREE ...... o VOLUNT .. RY ACT OF suc,i'~f,fHY ,oR fi.1~. USES ANO PURPOSES M[tHIONEO IN l .. E INSTRU\A[NT. ' ,• •.•. t_-,,l.-t;,f :· •: ... ;_ ',:,~~.;:,y;J.,~-.--_--~---:£-_-_.~_f_-_· -_· "_:-::-_:~.. ..... -r,·1::~~·t1."ttc;~~ .• ~ " L,. ~.,.f-_.,.,.,, \_:-.'.·Kt1'ARY ~1Jf:!~ _ I "'y """OINTMENT ExP,;.Es_J./:..~"':1:--:.f2!! ", :-:::,n: Of w.~Jl'N(l~,.-~, t PRtNT[O NAME CF •:. l\'.·,..,,,:tMl~Sl"!Ni~Jl'f~/1(-'/ "IOTA.RY PU8~LC_~lj!_~f.ijf_t,__~~ -l~~, ~·.· •••.•• ,,. "•, •. '.:.,. SOOS Cfl·~EK WATER 8. SEWER OISTRICT AN HS£M(NT IS HEREBY R<$ERYEO FO~.M~ CRA~TE0 TO PU(;il.SOUNO ENERGY, .. T & ! BRO...OOi.iJO CABLE T[L[,..$10N, QVo(Sl CCMMIJNIC,A110NS. THCfR·.~uCCESSo,t5 AN0,A.$l;iGN5, UNDER ANO UPON THE (Xl(RJOR /EN f[[T PARAUEL 111m A.~o AOJOlNINC,JiiE STREET 'JiaONUGCOF A.r.L'\O':'S II< WHICH TO INSTALL, LAY. CONSTRUCT, R(N(W, OP(RATE, ANO MArNTA,1-i-J,NOERCROUNl:i•~P{•,:CONDUlt, CABLES ANO MRES v,\ll-1 l<[CESSA.RY fA.C!UT1E5 _. A.ND OTHER EOIJ'Pl,l[Nl FOR NE PIJR~OS[ OF sc~viN~ THIS S\JBOl'ITSO.~ AND OTHER PROP[/HY 111TH RELATED .,· UT1LITI[S, TD(;[THE:11 111TH THE RICHT'IQ.[Nl(R UPON TH[ LOTh AT ALL T1t,1(S FOR Tl<E f>IJRF'OSES H[RE>N SlATJ;n Tli[S!: (AS(MUHS £NfEll[(1.WPOl FOR Tl<[S[ PURPOSES Sl<Aµ_ BE RESTORED AS NEAR AS POS$18LE TO lH[IR;,' OR•GJNAL CONOIT10N BY l}le·(ihl1TY.".•~O lLN(S OR 'M~ES fOR ,s1,1p UTIUT1ES SHALL !IE Pl.ACED OR P[Rt,1IT1IO J:Q BE l'I.AC'EO UPON A~\iOT UNLESS ™t,•,?.~l,lr,~.~~lL SE UNR(RGROONO OR IN A CONOUIT AIUO<(O TO• BUil.ta~, .• ~,...'i.cr fEes ~ DtSTRICT HAD NO RE(l(JtRD,!£Nl fOR P•YJ,/(NI r:J" SCHOOL ""PACT fHS ., Tl<E Tit,!( or f1Nll PLAT Al'PROV•L::,Al,.~E n ... ~ Of !IUllO•NG Prn ... 11 APPllCATJON, SC!<OOL 1'-'PACT f£ES SHA.LLB( tVALUAIEO, ANO ,r Af>P\JCABLE. K...NG CQ..NTY FNANCE DM9ION c'ERJFl¢AIE ·. ·. '. . I l<(R[BY C(RT1n mA.T •LL P.~DP(RTY TAXE~: .... RE P•Jb, THAI THERE AR[ NO DELINQUENT SP[OAI. A5S£SS ... [NTS C[Ri,r,rn TO fHO:-qr,FlCE: FOR CEIU(CnON ANO TliA.T A.LL. SPfCI ... L ASS(S51,!CNTS Ct:RllflEO TO THIS,l)HlCE F,,tiR COLi~CllON ON ~y Of THE PR::,PER_TY H(REIN CONTMIEO, DEOICATEO AS STREETS. ALl.!-fS OR r'* OTHE'l·fUBllC US(',O.R[ PAID IN fULL . SHALL BE ASSESSED (~SING THE ll,IPlCT f(E SC><EOULE 1,; rrrtcr Al THE Tlt,i( or PERMIT APPLICATION) •NO COLLEC'!O. ·')OCETHER IIOTH TH[ t(/RRENT AD'-'Jl"ISTRATictj FEE FOR EACN LOT. AO<)E~ \ l~f -~~-f,.OAY Of\--?J::::!~l'.-'=i---------------, 20£>_~ ALI. BUJ(DWG..~SPOOTS. >QOT1NC DRAINS, .-...0 DRAINS fROt,1 AI.L ll,l?t;Rli10US SURFACES SUCH AS PATIOS A'<O ·•.••• •',CIIIYEWAYS'!;H.ll_L !!'E CONNECTED 10 THE ?ERl,!ANENI SIORM DRAIN ourt.n AS S!-'01\N ON TliE lPP~O\KO ·;._ :... , ~:J:;;~~~E~G::.n:~\,: .. -~~r .. ~~i~,1~!Hof ~ys ~l~&{.i11 p~~l~.Ej,~'~g:!Efno'=t:f..r~~~l~~UST J~~;;~t~~\~,;;;;:J::-/ lifiiiffe.~~ , i;;~':,J;~c4A?~ ~(n )~ ~:~~ ~~¥£~ •l\. FEES R(OUIROO-SY I(~(;' C~/<T.'( XIOE t.o. 1<.75, l(lNG CO\J'ITY ROAD i,,nCAT10N PAY!'ENT SYSTt" (1,!PS), :;;~~~·.'.·.· .... fHE HOUSE 'Al:lORESS SY'SJ[i, FOR ili•S PLH SJsA.LL 8E AS rOLlOWS: ..00RESS£$ SH-'<.L BE •SS.CNEO FOIi lliE NORnt-S()UTM'RO ... OS v,rn ..... fH( RAAC( Of 1~400 TO ,~499 ANO \\ITHIN TH[ RANCE or N/A TO N/A F"()'l TH.£ E.ASI-WESI ~ios. IN0';10UA~ ADORESSES \'I\Ll BE "5SlCN(O JO fH( PRINCIPAL [Nlll>NCE or (AC!i .. ·.',lf($i!:E~S:E OR BU!Ltl~ ,N ACCOlioANCC 111TH KINC COUNTY COOE !6.08 ~__lE:~ECOROl~C No. Z..2..~0Jl~'Q_Q_.!'.'.:~--------- flLEO ~OR R[b;Ro.:.o'.l'··.<HE R[OU[ST OF 11,[ ~ING COUNTY COUNOL !HIS _u, ____ Dh or 1.i~.~L~-~Mi::::::&~.~.1s1°ftlrs :_~~ft~~~uii?~i; o1-;;~"'~~~~~~L~TON ····"::l~~~:~t;''.'.'. ____ _ ..w_&,;,1_ _ _w_~H!.Rli:L~~---------s;i~£mNTEND[NT Of ~(CQflOS •.-,. BE coi<'URUCTEO A.NO ,PPRQl'!;O PRIOR TO THE FINAL BUllO,NG INSJ>ECTION APPROVAL. f~ THOSE LOTS THAT ii.RE ·:-. OESJGN•Tfo.ro11 IN(llli1DL:AL LOT INflllRAT10N SYSTD•S, THE SYSlI'-'S SHA.LL BE COl<STRUC,CO AT TH( Til,f[ OF THE ··,·.8UILDING Prfti,111 ANO SHALL CCIJPL~ V,,TH PlANS ON nLt. AU. INOIIIIOUAL SnJB-OUTS SHAl.l et P~.VAl(Ll 0#-1(0 '""'? t,!AINTM<EI\BY TH( LOT hOM[ OM<ER l~llf'~,~AI Df LARSON PARKE. IS BASED ~.'PON ,\>j ACTUAL SURYEY '-ND SU90MSIOOI OF SECTION J2,')p~SHIP 2, NQIITH, RAAG( !, EAST w.i,., n<AT Th( COURSES ANO 0JSTANCES ARE SHOlloN CORRlCllY HEREON. THAl 0 °1lj( r,/bNUi.!ENT'S IIILL BE SET ANO.TH( LOI ANO !ll.OCK C(JIN(RS WU BE SIA.K(D CQRRECTt.Y ON THE GROUND AS CONSl'Ji.UC IS CUMPLE1£0 ANO •NO T}l•T I HAY[ FULLY COMPLIED \\IIH rn PAOVISIO,.S or n<E P REGUlATJONS P l E. \! RO P.L.S., C[RJjfJCAIE No 22962 Oll[Y-t,1()q~W-POBlEI(. INC 726 ~UBUA'I 'ilAV NQRJ,< AL'6URN. WASHINGTON, 98002 (2~.l) .l!J-2200 (FAX) !Jl-2200 DALEY-MORROW-POBLETE. INC. 77(;; ALJBUI?~' WAY 'IORT>< ALJClURN WAS><INCTON ;;eoo2 PHONE· (2!iJ)JJJ-2WO (fA~)JJJ-2206 D.D.E.S. Fil,£ N.9· L~ SHEET10F 2 ;, .-- LARSON PARKE . A replat of Lot 4, Bill Ruth Addition, Vol. 102/23 .·.· .. A portion of the S.E. 1/4, NE 1/4, Sec. 32, Twp. 23 N., Rge. 5 E., W.M. . ·:, 50 GR!PHJ~ .. s~~f.L. E ·····::.\~\ ~·· ,. IN ri:i:'U 1 Inch • so·it. MERIDIAN= . ·.: · .. w•s•fNGION S'l~T{·f.LANE. NO~IH 'roNi l<PGN ~/~I. l'[!l, •.C S.C. ·:\, BASIS'.OF BEAA1NGS, .• 1~c E. lN., ~!.·".>/•. s.:c.,i-,n':l-R:.£ . .'•1" BEARN:l'.~ 01'15'0(')" [ , •.• "' · ~·······<•······,· .... 9:c rOUNo 2· BRA~-p,s..:· . ..,-;·x·. -~ EASfioil<T LINE ,fc.s.c. ~~c cou~:' ... sv1w;:, it ... mot. \ (R) ~;,.i,,.I • ' \M) '-ltisu~b (~" :C~LC:,:l·~1t{' [f'J ..::mu_._liun1 Ao'Oi1,0N voi/ :n/2J 00 (e::;J EMEf!ALO GLEN, VOi. 1,("i/79-81 to, CCRl,os\ts.eE SET AS ot'sc~,ern 1'1 NOTE"~,SH;'Ef'l',9C],,·'' iii:.EERei;2es, ···::;1 ~.c,r•c ~CRT';'!Wf;ST.':;tU Co Y nSH•~CTCN. Ol!OH No. 3565<5. 1;1.1.!EO JANl:,llRY -1~.'.2~1. <. ~~~-:Rijjll AD0:~;0,,', \'O. l01/2J ~ O~[R~lO Cl[N, '{CL. t77/li-B1. ···~ ... s,«~,w.ooo osr,;it.s, vo, u11n-1s '46.00 •6.00' 2s.cxr •SOO' B500' -85.00' King CQunty, Washington ·· t ' , • '• ''" ', . "~7'~J~\~"W -rtR[ H\'ORAl,jl [AS£\!['11 ,,..---x~TING WATEfi°'q.i,m tJ..S(t.!(!,jT ' ~; • SET NOlt \4 SHEET I 0"; /~!(s ~1,,co 0 E ·1·';,1,v~:.', No uooioJ 6~ '--, '", {~6{~3';~~w 1 ~lo,.,o·po:t . ~ .,,, 5or " -L:sw ~ ".c,.'iili OJ • l ; o ?-.; , 0 •"'8"1 7 . \ ~•45 ;o'<s" / ~f r PJtl:.,~ Vl'AJl:f{ \IAI .. [AS[l,l[IT },.. ~.l.-.1 m ,mt,, SHEl\1~.iiC~· \.,. ~AIL 'B' ·-. __ sc .. _L_t: r·-20' -~ SCALt: I .;5'" fm'ArE DRANidf:EA~NT At,l~NA&r THE Ql',N(f{S o,·. PRIVA"ii. PROPERT'o/.'WITH!'I T""6 PLAT tNCU>.IB[REO WlTH '.)RAINACE; EASEME'HS s .... OWN AS "PRIVA~-. HER°l:Bv CRANi'.ANO CO'!<.\fEY TO ~li<IG COUNTY. A FOUT'CAL SU801VISION OF" THE s~ATE OF ::ri~~ T~~c;.~1f l'i~~gH ;L...ut;::;~R6t~l'~AT~~s" PI~ 7c~~~1~2~i~~;;, ~~~Ht~0 v,?~Rr :i~E R%';.Tf~r REASONABLE ACCE~ (l'ICRESS··~~O EGRESS). TO ENTER SAID DRAINAGE EASEMENT FOR TH[ PURPOSE OF gg~::~~g ~t~Eol:~·.~WNERS A (•:tROP[RLY OPERATING ANO "A!NTAININC THE 0/IAINAC( FACIUTIES THE O"""'Efiitb/·'·!i~IO PR:~:.i.l( Pl-lOPE~·'t;,.:..,RE RESPONS1BLE FOR OP[/IA,flJ,;G, "'ALNUl"IINC AN'.) REPAIRING Tl'<[ DRAINACE"FACl~LTIE5• CONTA•r..eo WlTHlh SAID OO'!AlNACE tASEME'IT, AND ARE HER>SY REQL.JIO'IED TO OBTAIN ANY R[OUIR(-C> ?[Rt.olTS. F1;Dl.t 'CHE K'WO colJNn:.~f:PARTM(NT or 0(\/ELOPMENT ANO ENVIRONMENUL SERVICES PRIOR 1'0 muNC, PIPi~G. CL.JTTING"',(:)R .110,~~.c. VEGETATION (EXCEPT F:;JR ROUTINE LA'IDSCAP[ MAINl(NAPsC[ SUCH i>S LAWN MO\lo1U(l) LN CPEN liECi"TA1tO DFl·lt.WACE FACIUTr[S (SUCH AS SWALES. C<,i>NNf:I.S, 01TCHES. PONDS: E1C.).>(lll PERP.ORl.41~ ANT ALTE~-.nONS &fl MOOWICATIO"S TO THE ORl>INAG( FACILITIES. CONTAINED WITHI"< \SAIO,,-ORA\ 0 NAGI'. fAS_~ ~~_T. •\.,. .? THl$°-•>'.:ciVEN,'INT ~,...,.:RLtli w,Tl{•THE L.ANO i"!,i.-1s B:NOLN~ UPON THE OWNERS Of SA:D PRIVATE PROPERTY, TH_;;1f<·'"'.i-1R~,'.SJCCESS0R1' i>NO A05SIGNS. . Kk.COU~-.~~~ A'~l•.DRAINAG[ [ASEMt'ITS ·W1THIN,'.THIS Pt.A.l. NOT SHO'NN AS "PRrVATE", ARE HEREBY CRANT[O ANO CONVEYtO .. ~~O~I~ .. ;.0~::i,Nt ::~~;it~~Ll~;~l~'c~IS~~~~f A:Hl S~T:rT!ct w:~S:l~~!O~fj:i~Gi~ic:~~ii;,Nr A('POP"-~'J~;rJ, :'."'>;QR rn,s··J"'(,/IT BY KING"'tOLJNJ)'.: TOC!:rH~fl WITH THt RIGHT Of REASONABLE ACCESS (1NCRESS ANO EGRESS). '. rb:<;NHR S.o:.-Q_ DR"NAGE EASD:l[NT roR TH[ PUJ{POSE 0:-l'IJSPECTINC. OPERATING. I.AAINTAINLNG, R[PAIR·•rn A"o"·\MPROV1N°Cl•,l'-<E ORA,NAGE',"FA:;ILITl[S CONTAN[O THEREIN. NOTE !HAT nctPT fOR THE fACILITltS WHICH HAVE 8tEN fOR!J~LV ACCE,f'.tEo •o<. r..tAl'ITENANC[ {lY KING COUNT'r, "'AINT[NANCE Of DRA1NACE F"AClllTIES :IN PR1v.o.'.t~ PROPE'.~:t'f. IS,-~E O'IESPONSlalLITV OF TH[ PROPERTY 0 .... "N(R. '·:l:'JE O"NE~~:"Qf SAID ·~~l~ATE PROPER<Y ARE RCO<.;IREO TO OSUtN PRLOR WPITT[N APPROVAL ff{CM KING CO\JNTY PRCPl':IHY SERV1CES, AND ANY REDUIREC PER ... t<S mo ... T-<E KINO COUNTY DEPAFHM[NT CF DEVE'~OP>,rnr AND .. ~N,,,RONMENTAL SERVICES SUCH AS CL~ARLNC A'ID GRADING, PRIOR TO FILLING, PfPl'IC, CUTTIN'~.O!l RHtO~mo \i[CEIATION ( (XCEPT FOR ROUnNE LANOSCA?[ MAINT['IA"1CE SUCH AS LAWN ... OWl"G) LN QPE:'l 00 Vl;C~TATEO tlij/'l"ACE FACIL111ES (SUCH AS SWAl[S, C~ANN(LS, DITCHES, PONDS. ETC,,) OR P(Rl'Olhl('-G i>NV AC:1{RAllONS OR ... 001~,CATLONS TO THE O~AINAGE l'ACILrncs. CONTAINED WITHIN SAID OR/\,NAC!: EA°SH<ENI THIS EASE ... ENT "ii:.mTtNOE~·\10 .. rACILITATE REASONA8LE ACCE!;S TO THE DRAINAGE rAC!LtlES. THIS EASEM[N: /\NO COVENANT Si-<l<t'<,-RU'l WITil· [HC LANO AND IS SINO,NO UPON T,__.t OWNERS or Sl<1D PRIVATE PROPERTY, THEIR H£1~S. succtsso~. ""~i"ASSICNS. ~~··.,/ THE 10 •001 s1:wsR EAS(MENT OCPICTED HER!:ON ,s 1-<EREBY ')[CICATED ANO ::CONVEYED TO SOOS CR~EK w,o.TER ANO SEWER O•SIRICT, ITS SUCCESSORS ANO ASSIC"IS. FOR THE PURPOS!: Cf INSTALLING, OPEr~l><·NG i>ND MAINTA,NING A PUBLIC SANITARY SEW£R CONl'CVA:-lCE SYSlf.M .. -:·.:::~~2:~.~~ --~ACl "A" IS ·,{<1ECRt·.i..1ir1 TRACT AS) tS !:ONSIIJH[C A "JR,C! PU<!StoANT JO ~CC 19A.04 JXl DALEY-MORROW-POBLETE, NC. 726 AUIJURN WAY NORTH AUSURN. WAS,.HNCTON !11!002 '"1(-·:;JRACT" IS LANO hESESV[o FOR SPECw,c USES. NClUD,NC ~~T NOT L'\!11(0 TO. R[ffRVE TR~815. RfrnfATIQN OF'[t.",SPAQ:, S[hSl;T>'i: ,tRUS. SURrACE WAT(R R[T[hJl()l,I, u;,uTY fAC~IT1[5 AND ACCLSS. 'RAC1S AR( NOT CONS.O~io LOIS 0~ 8U'4!lrlG S'l[S rn~ Pl,R~O~[S or R!StC[NTIAl OW!:WNG CONST~UCTION .,,. SHEET 2 OF 2 PHONE. (253)333-noc (FAX)J33-22D6 i1Jur~ EN<>N~NGPLA~NG •!iJ37f~ u 11 AUG Jl r I I I I I I I I I I I I I I I I I I / FINAL CORRECTED T.I.R. TECHNICAL INFORMATION REPORT FOR LARSON PARK CLIENT: J: G. REAL ESTATE GROUPN.W., LLC 18124 Riviera Pl. S. W. Seattle, WA 98166 Phone: (206) 919-6066 PREPARED BY: Daley-Morrow-Poblete, Inc. 726 Auburn Way North Auburn, WA 98002 Phone: (253) 333-2200 PROJECT No. 99334 DATE: March 14, 2000 REVISED'. J/>.f-l. 121 i'.001 CONSULTANT REVIEW TO THE BEST OF MY KNOWLEDGE. THIS PLAN HAS BEEN REv1EWEO , FOR COMPLIANCE WITH KING COUNTY CODES AND ORDINANCES. N:1~1v.07 /-/t;-o; (42sJ 204-8182 DATE PHONE CASEY ENGINEERING FIRM FINAL CORRECTED PLAN DATE: 1/gh i... I 7 APPROVED: I EXPIRES 9 J,:\N 2002. STAf.lf> NOT VALID UNLESS SIGNED & DATED I I I I I I I I I I I I I I I I I I I TABLE OF CONTENTS DESCRIPTION SECTION I PROJECT OVERVIEW Project Overview Vicinity Map -Exhibit A TlR Worksheet Soils Map -Exhibit B SECTION II . CONDITIONS AND REQUIREMENTS SUMMARY Preliminary Plat Conditions Variance LOOV0092 SWM Adjustment SEPA Determination of Nonsignificance S0-220 KC. Code Sec. 16.82.150D Response to Plat Conditions Response to SWM Adjustment SECTION Ill OFF-SITE ANALYSIS Downstream Analysis PAGE 2 3-5 6' I:.. 7 7a-7d 8-.JO II -12 l2a-12g 12h . 13-'-14 15 l -32 SECTION IV FLOW CONTROL AND WATER QUALITY FACILITY ANALYSIS AND DESIGN Existing Site Hydrology Existing Condition Drainage Map Data for Existing Condition-On-site & Off-site Performance Standards Developed Condition Hydrology Developed Condition Drainage Map Data For Developed Condition -On-site Performance Standards Detention Facility Design . Emergency Overflow Spillway Vertical Grate Design Wetpond Design SECTION V CONVEYANCE SYSTEM ANALYSIS AND DESIGN Conveyance System Design SECTION VI SPECIAL REPORTS AND STUDIES SECTION VII OTHER PERMITS SECTION vm T.E.S C. ANALYSIS AND DESIGN Sediment Pond Design· Narrative for ESC Plan SECTION IX BOND QUANTITIES AND FACILITY SUMMARIES Bond Quantities Worksheet Storm Facility Summary Sheet Pond Detail SECTION X OPERATIONS AND MAINTENANCE MANUAL I 2 3 4-6' 7 8 9 lO -l I 12-17 18 . 19 20 I -5 NIA NIA I 2 1-9 10 -11 12-14· NIA ------- I I . I I I I I SECTION I I PROJECT OVERVIEW I I I I I I I I I . I I I I I I I I I .I I I I I I I I I I I I PROJECT OVERVIEW Larson Park is located on a 2.06 acre parcel located in the Southeast, quarter of the Northeast quarter of Section 32, Township_23 North, ~ange 5 East, Willamette Meridian, King County Washington. The proposed project will consist of the creation of 14 single- family residential lots. The property is also known as Lot 4 of Bill Ruth Addition and is· located near SE 183rd Street and 112'h Ave. SE .. All necessary utilities and 'stormwater facilities will be constructed to serve the development. This report is being prepared pursuant to the 1998 King County Surface Water Design Manual (SWDM). On-Site Drainage Analysis This project site is situated within the Panther Creek sub-basin of the Black River Drainage sub-basin of the Green River basin. Presently, the site contains an existing residence near the center of the site. The remainder of the site is undeveloped and is covered with pasture grass and a sparse scattering of shrubs and trees native to the Pacific Northwest. The ground slopes from the northeast corner of the site to a low point at the southwest corner of the site. There is a half-acre offsite tributary area to the site. Runoff from the site flows to the southwest to be intercepted by the existing drainage system along the eastern side of I 12th Avenue S.E: The soils on the site are Alderwood Gravelly Sandy Loam (AgB) as classified by the US Soil Conservation Service:· Upstream Drainage Analysis This site is located within the Panther Lake sub-basin· ofthe Black River brainage'~ub~ · basin of the Green River basin. There is a one half-acre area which drains onto the site from the east. Downstream Drainage System Description As discussed above, the flow from the site discharges to the eastern side of J l21h Avenue S.E. where it is collected by the existing drainage system and routed through the "Ruddells" detention pond at the northwest corner of SE !84thPlace and J l21h Ave. South. From there the flow is piped on to the "Maple Glen Regional Pond" to the northwest at the southeast corner of SE 182"<l Street and I 081h Ave. SE. Future Site Conditions An appropriately sized conveyance system will be designed and constructed to collect the developed on-site runoff from the proposed project. Given the proposed layout of the project, flows from the site will be collected and conveyed to the water quality and water quality facilities for discharge to 112th Avenue S.E .. The stormwater facilities will be constructed pursuant to King County Standards for level 3 ·detention in order to insure that the downstream drainage problems are not aggravated. The detention pond will be .. constructed at the west end of the site. 0 I I I • I , .. lJZIIJ AV I I I i """ ~ I 1'8Til ·-i S( I > lSllll AV A ', ® I I ···-. ) I I I I I I I I ') I I I I I I I ) I I ---· . . King County Department of Development and.Environmental Services TECHNICAL INFORMATION REPORT (TIR) WORKSHEET i;r~~f:tj~j~~j~f ~~~~r%:!;it\l:\';.(~l:~~~\ Project Owner J.G. {lti'\I, 6-!;"T'ATc Gfl.al.lP /VIJJ L1.C Address /~JZ't fl..(V1E./I-I\ fl. S. ()). Project Engineer · · · ,. · Met.. D1\tE7'1 f."- Company D rll f' f.N C • Address/Phone 2. S 3 • 3 33 · 1-7...0 0 i/subdivison · Short Subdivision · Grading Commercial Other ______ _;.. __ Community soo.s: Drainage Basin River Stream __________ _ Critical Stream Reach Depressions/Swales Lake __ --'--------~ Steep Slopes--------- l1ii~~~~Tu!~ij~~M~r~~f ~~{;j~~t1ifot::, :.;·· ... Project Name tAASO~.· /'l,'1-~ Location ', .. DFWHPA COE404 Shoreline Management DOE Dam Safety . FEMA Floodplai~ .. COE Wetlands Rockery Structural Vaults Other ,.:, .... . ~ ~ .,.• . ~-... . ' . . ' Floodplain-------'--- Wetlands ..,---------'- Seeps/Springs High Grouridwater Table Gmundwater Recharge .·Other· D~v,1»S:r1tc.ll\"": R6s711-1.c •10;,J' , .. .. 1. ' . ® I I I I I I I I I I I I I I I I I I I .· · PartT .,SOILS' Soil Type AlDa/1.WOOp "aa Slopes· 9.<-t, :Yo Additional Sheets Attached Pait'i3,,DEVElf0P~ENT1UMITi\;f.lONS REFERENCE Ch. 4 Downstream Analysis Additional Sheets Attached ,· --. : ... _ .. :,_ ··· .. ·-·-·._·. . ': .. \ '' ,•~art;9fES.Gl'll;.QlJIIJEMEtJTSV ... ~.. ' MINIMUM ESC REQUIREMENTS DURING CONSTRUCTION " Sedimentation Facilities " Stabilized Construction Entrance "Perimeter Runpff Control "\ Clearing and Graing Restrictions "cover Practices "-construction Sequence Other Erosion Potential SLl<;r\T Erosive Velcoties 2., 1/ps LIMITATION/SITE CONSTRAINT · LGve.1. · ~ . uir-reNT10AJ U~1J1,-co . . MINIMUM ESC REQUIREMENTS AFTER CONSTRUCTION " Stabilize Exposed Surface '-.. Remove and Restore Temporary ESC Facilities '\ Clean and Remove All Silt and Debris· · '-Ensure.Operation oi'P~rmanent Facilities . . . Flag Limits of SAO and op·en space prnservation :i,reas · ·, Other I I I I ii :I I I I I I I I I I I I . •;, .. , .. , . ·.:···;,.· '., ,, ' . >Part'10,: SURFACEWATERSYSTEM . · .. :. ,.. ' ., Grass Lined \ Channel Pipe System Open Channel '\ Dry Pond ·Wet Pond Tank Vault Energy Dissapator Wetland Stream I ; ' Infiltration: , Depression !;low Dispersal Waiver Regional Detention Method of Analysis -kC/?.T'c:> · ·. Compensation/Mitigati on of Eliminated Site Storage ,Jet -NA Brief Description of System Operation $17€ R.OtVOFF Ta /.!,£; 6JNV€'1eO 7o a?/4/!JtNEO /)£7£/\ITJofJ /'~NIJij£T,OoNLJ, L.ivcl .3 Fl-dtJ C<JN71l,o/. Facility Related Site Limitations C/l.l7c.R,1A {,(56£) Fo.e 9/cJNG. Reference Facility Limitation : Paiti1:t{stRucTl!IRALANALvs1s· • •· .,-:· ,,·::.:: ... ,,, . ·.,.. '· .·· Cast in Place Vault \ Retaining Wall Rockery > 4' High Structural on Steep Slope Other : Part 12, EASEMENTS/TR,A9TS -.... Drainage Easeme.nt . '\. Access Easem~ni' · ··· .-· Native Growth 'Proiectio~ Easement '-Tract Other 1 -' Pait 1 s.:···s1GNATURE OF' PROFESSIONAL, ENGINEER ' I or a civil engineer under my supervision 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. I I I I I ·1 I I I I I ,\-,.JH:!• "l. BM . : .. : . • • . 203·', .. 169 . ""AgC "'= • •. I -· . •• I /• : I ·J".~'·,~ I' -. ·I ·I . .. A8B SOtL5 lv14P AgC EXl-lt B·tT 8, © I I I I I I I I I I I I I I I I I I I ---' . . . SECTION II CONDITIONS AND . REQUIREMENTS SUMMARY ( . I •• I I I I I I I I I I I I I I I I I OFFICE OF THE HEARING EXAMINER KING COUNTY, WASHINGTON 850 Union Bank of California Building 900 Fourth Avenue Seattle, Washington 98164 Telephone (206) 296-4660 Facsimile (206) 296-1654 November 19, 1999 REPORT AND DECISION ON APPLICATION FOR PRELIMINARY PLAT APPROVAL SUBJECT: Department of Development and Environmental Services File No. L99P0003 Location: Applicant: · LARSON PARKE Preliminary Plat Application North of 1841h Avenue Southeast (if extended) at the existing stubbed portion of 114th Avenue Southeast. · M. Burnett Larson, represented by . Mel Daley, Engineer Daley-Morrow-Pobleie,.Inc. 1215 South Central Avenue #133 Kent, WA 98032 SUMMARY OF RECOMMENDATIONS: Department's Preliminary Recommendation: Department's Final Recommendation: Examiner's Decision: PRELIMINARY MATTERS: Application or petition submitted: Complete application: EXAMINER PROCEEDINGS: Hearing Opened: Hearing Closed: Approve, subject to conditions Approve, subject to conditions Approve, subject to conditions February 23,1999 March 17, 1999 November 18, 1999 November 18, 1999 Participants at the public hearing and the exhibits offered and entered are' listed 'in the attached minutes. A verbatim recording of the hearing is available in the office of the Kirig County Hearing Exami1:1er. . I I I I I I I I I I I I I I I I I I I L99P0003-Larson Parke 2 ISSUESfTOPICS ADDRESS.ED: • Surface water drainage SUMMARY:·· Subdivision of 14 lots on 2.06 acres in the Urban Area is ~ppr.oved: subj~ct t<? conpitions. FINDINGS, CONCLUSIONS & DECISION: Having reviewed.the.record.in this matter, the Examiner now makes and enters the following: . FINDINGS: I. General Information: 2. Developer: Engineer: Location: STR: Zoning: Acreage: Number of Lots: Density: Typical LotSize: Proposed Use: Sewage Disposal: Water Supply: Fire District: School District: Complete Application Date: Bernie Larson 26207 Woodland Way S. Kent, WA 98031 Daley-Morrow-Poblete, Inc. 1215.South Central Ave. #133 . Kent, WA 98032 . North ·of the existing st~bbed portion of 114th Avenue Southeast, east of 112th Avenue Souiheast. Access will be from I I 4th Avenl\e Southeast. 32-23-5 R-8 2.06 I~. 6.8 units/acre Approximately 3,500 to 4,000 square feet Single family residences Soos Creek Water & Sewer District Soos Creek Water & Sewer District King County No. 41 Renton March 17, 1999 The facts set forth in the King County Land Use Services Division's Preliminary Report to the King County Hearing Examiner for the·November 18, 1999 public hearing are found to be correct and are incorporated herein by this reference.· The said report is Exhibit No. 2 in the hearing record. I I I I :I 'I ' :I I I I I I I I I I I I I. L99P0003-Larson 1•arke 3 CONCLUSIONS: I. 2. 3. 4. If approved subject to the conditions recommended below, the proposed subdivision will comply with the goals and objectives of the Ki~g County Comprehensive Plan, Subdivision and Zoning Codes, and other official land use controls and policies of King County. ' If approved subject to the conditions recommended below, this proposed subdivision will make appropriate provision for the public health, safety and general welfare and for open spaces, for drainage ways, streets, other public ways, transit stops, potable water supply, sanitary wastes,. parks and recreations, playgrounds, schools and school grounds, and safe walking conditions for students who only walk to school; and. it will serve the public use and.interest. The conditions for final plat approval recommended below are in the public interest and are reasonable requirements to mitigate the impacts of this developm~nt upon the environment, The dedications ofland or casements within and adjacent to the proposed plat, as recommended by the conditions for final plat approval or as shown on the proposed,preliminary plat submitted by the appli~ant, are reasonable and necessary as a direct result of the development of this proposed plat. DECISION: The proposed subdivision of Larson Parke, as revised and received on July 28, 1999, is granted preliminary approval, subject to the following conditions of final plat approval: I. 2. 3. 4. 5. 6. Compliance with all platting provisions of Title ·19 of the King County Code. 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. The plat shall meet the base density of the R-8 zone classifi~ation. All lots shall meet the minimum dimensional requirements of the R-8 zone classification or shall be generally as shown On the face of the approved preliminary plat, whichever is larger. Minor revisions to the plat that do not result in substantial changes may be approved at the discretion of the Department of Development and Environmental Services. · The Applicant must obtain final approval from the King County Health Department. . . All construction and upgrading of public and private roads shall be done in accordance with the King County Road Standards established and adopted by <;Jrdinance No. 11187, as amended. The Applicant must obtain the approval of the King County Fire Protection Engineer for the adequacy of the fire hydrant, water main, and fire flow stand~rds of Chapter 17.08 of the King County Code. @ I I I I I I I I I I I I I I I I I L99P0003-Larson Parke 4 7. Final plat approval shall require full compliance with drainage provisions set forth ,in King County Code 9.04 and the storm drainage requirements and guidelines as established by the Surface Water Management Division. Compliance may result in reducing the number and/or location of lots as shown on the preliminary approved plat The following conditions represent portions of the Code and requirements and shall apply to all plats. 8. 9. 10. a. b. C. Drainage plans and analysis shall comply with the 1998 King Couniy Surface Water· Design Manual. DDES approval of the drainage and roadway plans is required prior to any construction. Current standard plan notes and ESC notes, as established by DDES Engineering Review, sha!Lb,c;. s.liown on the engineering plans. '1 ~ ....... : • The following note shall be shown on the final recorded plat: "All building downspouts, footing drains, and drains from all impervious surfaces such as patios and driveways shall be connected to the permanent storm drain outlet as .shown on the approved construction drawings #_on file with DDES and/or the Department of Public Works. This plan shall be submitted with the application ofan t building permit. All connections of the drains must be constructed and approved prior to the final building inspection approval. For those_ lots that are designated for individual lot infiltration systems, the systems shall be constructed.at the time of the building permit and shall comply with plans n file;" The Applicant has received approval for the requested diversion of surface water within the project (see Drainage Adjustment L99V0343). All conditions of approval for this adjustment shall be met and shown on the engineering plans. · The design of the stormwater detention facility shall meet the Level 3 KCRTS Ffow Control Methodology, according to the 1998 KCSWDM. Other mitigation scenarios may be considered · according to Section 1.2.2.2 of the KCSWDM (Impact Mitigation). Off-site drainage improvements are required to convey stormwater to the west across private property to 112th Avenue Southeast, then south along the east side of 112th Avenue Southeast, . then west under 112th A venue Southeast to an existing detention facility (Ruddells Pond). These improvements shall be designed according to the 1998KCSWDM. Permission for construction of off-site private property drainag·e improvements is required to be submitted with engineering plans. The proposed subdivision shall comply with the 1993 King County Road Standards (KCRS) including the following required road improvements: a: Southeast 1 s3rd Court shall be improved _to the urban minor access road standa;d.· I I I I I I I I I I I I I I I I I I I L99POOOJ-Larson Parke s 11. 12. 13. 14. 15. b. C. 'The west right-of-way line for ihe north extension of existing I t4th·Avenue Sotith;,,~t . . ' ... ··. .· '· . ... . .. ' shall extend to the north property lme.ofthe site.. · Tract B shall be impro~ed as a private acc·ess tract per Section °2.09, ofthe KCRS .. Tra~( B shall be dedicated to King Coun!y for access .tci the·stormwater detention facility, with an access/utili!y easement granted to Lots 12, 13 and 14. The easement shall be shown on the engineering plans and final plat. d. Modifications to the above road conditions may be considered pursuant to the variance procedures in KCRS. 1.08. KCC 16.82. I SOD requires seasonal limitations for construction within the Soos Creek Communi!y Planning Area. During the period from October !-;-through March 3·1,. clearing and grading is not allowed unless certain provisions are complied with as outlined in the. code. The Applicant's engineering plans and construction procedures shall demonstrated compliance with the applicable code requirements. All utilities within proposed rights-of-way must be incluqed,within·a franchise approved by _the King Coun!y Council prior to final plat recording. · The Applicant or subsequent owner shall comply.with.the King Coun!y Code 14.75,.Mitigation . Payment System (MPS), by paying the required MPS {ee and administration fee as determined by the applicable fee ordinance. The Applicant has the option to either: (I) pay the MPS fee at final plat recording, or (2) pay the MPS fee at the.time of building permit.issu~~ce,.. !ft.he first. opti~n is chosen, the fee paid shall be the fee in effect at the time. of plat application and a note shall be placed on the face of the plat that reads, ."All fees required by King Coun!y Code.14.75,, .. Mitigation Payment System (MPS), have been paid;" if the second option is chosen, the fee paid shall be the amount in effect as of the date of building permit application. Suitable recreation space and facilities shall be provided in Tract A consistent with the requirements ofKCC 21A.14.180 and 190. An overall conceptual recreation space plan shall be submitted for review and approval by DDES, with the submittal of the engineering plans. 'This plan shall include location, area calculations, dimensions, and general improvements. The approved engineering plans shall be consistent.with the overall conceptual plan. · · A detailed recreation space plan (i.e., landscape specs, equipment specs, etc.) consistent with the overall conceptual plan, shall be submitted for review and approval by ODES and King County Parks prior to or concurrent with the submittal of the final plat documents. A performance bond for recreation space. improvements shall be posted prior to recording of the plat. A homeowner's association or other workable organization shall be established to the.satisfaction ofDDES to provide continued ownership ofthe,recreationtract arid its facilities; and maintenance of the recreation facilities and associated landscaping, street trees, and walkway. ® I I I I I I :, ' I I :1 I I I I I I I ' . l.99POOOJ-Larson Parke 6 16. 17. The following condition shall apply to implement the P-suffix conditions to this property: S0-220 (Significant Trees):. Significant trees shall be retained in a residential subdivision at the rate of20 trees per acre or ten percent of such trees, whichever is greater. A significant tree inventory shall be submitted for review prior to or with submittal of development pe~mit applications. A detailed tree retention plan shall be submitted for review prior to or with submittal of grading permit applications or other permit applications involving grading plans. Lots within the Larson Parke subdivision are subject to King County Ordinance IO 162 and .. Ordinance 12532, which imposed impact fees to fund school system improvements needed to serve new development. As a condition of final approval, fifty percent (50%) of the impact fees due for the plat shall be assessed and collected immediately prior:t<>. recordii_1g, using the fee schedules in effect when the plat received final approval. The balance ·of the assessed fee shall be allocated evenly t<l'the"dwelling units in the plat and shall be coi'lected prior to building permit issuance. ORDERED this 19th day ofNovember, 1999. es N. O'Connor ing County Hearing Ei<~miii'er ·. TRANSMITTED this 19th day of November, 1999, to the following parties and interested persons: Loretta Aschenbrenner Mel Daley Bill Graves Ken Lower Paul Morrow Keri Akers Nick Gillen Aileen McManus Bruce Whittaker Mark Asman Roger Dorstad M. Burnett Larson Linda Matlock Seattle-King County Health'Dept.' Greg Borba Kristen Langley Steven C. Townsend C. J. and Irene Bernards NOTICE OF RIGHT TO APPEAL Paul and Mary Ann Dowd Joh~ Gresham and Cheryle Lemelle Eleanor Moon D.E. Welman Ki'm·Ciaussen Suzanne Louie Larry West In order to appeal the decision of the Examiner, written notice of appeal must be filed with the Clerk of the King County Council with a fee of $125.00 (check payable to King County Office of Finance) on or before December 3, 1999. If a notice of appeal is filed, the original and six (6) copies of a written appeal statement specifying the basis for the appeal and argument in support ~f the appeal must be filed with the ~Jerk of the King County Council on or before December JO, 1999. Appeal statements may refer only to facts contained in·the hearing record; new foe.ts may not be presented 'on a~pea1: I 1 !1 :1 'I I I I I I I I I I I I I.99P0003-Larson Puke, 7 Filing requires actual delivery to the Office of the Clerk of the Council. Room 403, King rounty Courthouse, prior tO the close of business ( 4:30 p.m.) on the date due. Prior mailing is not sufficient" if itctual receiPt by the Clerk does not occur within the applicable time period. The Examiner does not have authority to extend the time period unless the Office _of the Clerk is not open on the specified c~osing date; in which event delivery prior to the clo·se of bllsiness on the next business day is sufficient to meet the filing requirement. If a written notice of appeal and filing fee are not filed within fourteen ( 14) calendar days of the date of this report, or if a written appeal statement and argument are not filed within twenty-one (21) calendar days of the date of this report, the decision of the hearing examiner contained herein shall be the final decision of King County without the need for furt_her action by the Council. MINUTES OF THE NOVEMBER 18, 1999 PUBLIC HEARING ON DEPARTMENT OF DEVELOPMENT AND ENVIRONMENTAL SERVICES FILE NO. L99P0003-LARSON PARKE: James N. O'Connor was the Hearing Examiner in this matter. Participating in the,hearfag-and representing the Department were Keri Akers and Bruce Whittaker. Participating in the hearing and representing the Applicant was Mel Daley. The only other participant in this hearing was Ken Lower, an Interested Per.son. The following exhibits were offered and entered into the record: Exhibit No. 1 Exhibit No. 2 Exhibit No. 3 Exhibit No. 4 Exhibit No. 5 Exhibit No. 6 Exhibit No. 7 Exhibit No. 8 Exhibit No. 9 Exhibit No. I 0 Exhibit No. 11 Exhibit No. I 2 Exhibit No. 13 Exhibit No. 14 JNOC:sje Plats\L99P0003 RPT Department of Development and Environmental Services File No. L99P0003 Department of Development and Environmental Services Prelimin~ry Report, d~ted I l/4/99 Application dated 2/23/99 Environmental Checklist dated 2/23/99 Declaration of Non-significance. dated 10/5/99 Affidavit of Posting indicating 3/24/99 as date of posting and 3/23/99 a the date the affidavit was rcc.eived,by the Department of Development and Environmental Services. Plat Map dated 7/28/99 Land Use Map --Kroll page 604E "Assessors Maps 32-23-5 Certificate of Water Availability, dated 2/23/99 Certificate of Sewer Availability, dated 2/23/99 Certificate of Transportation Concurrency. dated 2/23/99 Level One Downstream Ana)ysis, dated 7 /28/99 Conceptual Drainage Plan, dated 7/28/99 I I I I I :1 I I I I I I I I I I I ® King County Road Services Divlfi:ion Department ofTransportalion 201 South Jackson Street ScaulciWA 9ll104-3l\56 Mel Daley, P.E. 726Auburn WayN Auburn, WA 98002 . RE: Road Variance--Larson Parke --LOOV0092 --Related File L99P0003 D_ear Mr. Daley: January 8, 2001 Thank you for your application for a road variance from Sections 2.12:0:2 and 2.08 of the King County Road Standards (KCRS) concerning stopping sight distance and cul-de-sac length .. The sul:?division of lli' ' ' ''' Larson Parke proposes to extend the dead erided 114 Avenue SE an additional 300 feet and add a cul- de-sac bulb. Also, a private road in a tract is proposed that will have inadequ~tc stopping sight distance where the road's vertical crest curve intersects 1141h Avenue SE. You have sufficiently explained the site constraints in designing a conforming vertical curve. In.· addition, you have agreed to provide access to the private street by means of a driveway curb drop that will control (reduce)' actual vehicular speed at the location where the stopping sight distance is diminished. · · The cul-de-sac length at 878 feet is over the KCRS 600-foot standard, however, there appears to be adequate provisions, via plat conditions, made to permit completion as a through road in the future. I approve this variance for cul-de-sac length on 114m Avenue SE/SE 183nl Court. I will not require an on-site or off-site reconstruction to provide a mid-point turnaround. I conditionally approve the variance for the reduction in stopping sight distance·on the private road serving 3 lots. The ~equirement shall be that the private road connect to U4m Avenue SE across either (a) a rolled curb/gutter and.sidewalk section, or, (b) a driveway curb drop (KCRSDwg. 3-004/ 005)- rather than by a radius return configuration indicated on the plat map sub~itted with your application. A copy of the stall's analysis, findings and conclusions is enclosed. If you have any.questions, please call Kristen Langley, Supervising Engineer, Traffic Engineering Section, ai (206) 263-6121. ' · Sincerely, ~J!jt/a~ Ronald J.Paananen, P.E. County Road Engineer cc: , James Sanders, Development Engineer, Department of Development and Environmental Services (DOES) Linda Dougherty, Acting Manager, Road Services Division (RSD), Department of Transportation (DOT) Paulette Norman, P.E., County Traffic Engineer, Traffic Engineering Section, RSD, DOT Kristen Langley, Supervising Engineer, Traffic Engineering Section, RSD, DOT I I I I :I I I I I I I I I I I I I Mel Daley, P.E. January 8, 2001 Page2 bee: Craig Comfort, P.E., Road Variance Engineer, Traffic Engineering Section, RSD, DOT Robert Eichelsdoerfer, P.E., Senior Enginet,T, Traffic Engineering Section, RSD, DOT Aileen McManus, Senior Engineer, Traffic Engineering Section, RSD, DOT r I I I I •• ' :I I I ·• I I I I I I I I I I January 8, 2001 TO: Variance File FM: Craig Comf~rt, Road Variance Engineer, Traffic Engineering Section RE: Road Variance --Plat of Larson Parke --LOOV0092 --Related File L99P0003 · Applicant's Presentation: I. Proposed Tract B will serve three lots and is required by Section 2.09.B of the KCRS to meet minor access street standards. The actual tract will be dedicated to King County for stormwater facility access .and also be encumbered with, private access easements for the lot access. 2. The proposed 40-foot long vertical curve (on Tract B) at the intersection with 1141h Avenue SE has 71 feet of stopping sight distance and not the requisite 125 feet. 125 feet of sight distance would require a 152-foot vertical curve and the tract length is only 129 feet. 3. The sharp vertical curve design is necessary to meet the 15% road grade. To improve the crest sight distance by providing fill at the far end of Tract B (and raising the road) would result in access problems for the lots adjacent to the tract. Lowering I 14th Avenue SE to improve the crest sight distance is impractical as access problems to an existing driveway wouldresult. 4. The stopping sight distance entering the tract road is adequate; the sight distance is impaired in the opposite direction. Less stopping sight distance is required travelling toward the intersection because cars would all but stop at the intersection. · · 5. The cul-de-sac is 618 feet in length measured from the road inkrsection wit,h SE 185th Place. There is a high probability that 114°' Avenue SE will be.extended to the north with future development to meet with the existing southerly road stub some 330 feet away. Staffs Findings and Conclusions: I. Topographical site constrainis (15% road grade on short private tract road) make the design of a stopping sight distance (SSD) conforming vertical curve a near impossibility. 2. The private road in Tract B will only serve three lots and provide access to a County stormwater detention facility. 3. The SSD entering the tract ( over the crest and down the grade) is approximately 71 feet if measured six feet back from the road (l 14'h Avenue SE) centerline. In the opposite direction, the SSD driving up the tract road is roughly 77 feet. Both SSD (entering and leaving the tract) are short of the requisite 125 feet. 71 feet of stopping distance roughly corresponds with a 14-mph vehicular speed. If the approach to the Tract Broad is constructed as a.driveway curb drop, vehicles would be forced to all but stop at the intersection, and the reduced sight distance should be adequate. The design of the tract road as a T intersection will also diminish speeds for traffic turning into the private road. The driveway approach design would hav'e' the added benefit of reducing the amount of traffic on the tract road as on]y.thelot owners.and visitors would utilize the access. ® I I I I I I I I I I I I I I I I I I I Variance File January 8, 2001 Pagc2 4. The proposed· cul-<ie-sac is 878 feet long as measured from the intersection with SE 186 1 • Street. 5.. Given the likely probability that 1141h Avenue SE will be extended in the future, this part of the variance should be approved. The applicant is being required by DOES to provide property rights for the future road extension to the north. CC:dt I I I I I I 'I I I I I I I I I I I I I -DDES , .. ® ::, King County Department of Development and Envlron~ental Services . 900 OakesdaJe Avenue Southwest Renlon, WA 98055-1219 September 28, 1999 Virk, Inc. 3010 l28 1h Avenue NE Bellevue, WA 98005 . Mel L. Daley, P.E. . DMP, Inc. 1215 Central Avenue South Kent, WA 98032 RE: Larson Parke Subdivision SWM Adjustment Request (File No. L99V0343) · Dear Applicant and Engineer: The Land Use Services Division, Engineering Review Section, has completed review of the adjustment request for the Larson Parke subdivision. You are. requestirig approvaf for ail adjustment from the 1998 King County Surface Water Design Manual (KCSWDM) Core Requirement No. 1, Section 1.2.1, Discharge at the Natural Location. Our review of the information and a site visit provides the ronowing findings: . · . · · ,· · ,, ' • j . • . •• • • • • . 1. The proposed Larson Parke subdivision is located at I 14th Avenue SE and SE 183rd Court. The 14 lot, 2.1 acre, proposed Larson Parke subdivisfoi°i is 'filed under Land Use Services Division (LUSD) file number L99P0003. · 2. The Larson Parke subdivision is located in the Panther Creek subbasin of the Black River basin. The parcel is subject to the Level One flow control and Basic water quality requirements of the 1998 KCSWDM. 3. The rectangular shaped lot, with its longest length in an east/west direction, sheet flows from east to west. In its present state with a single residence, sheet flow leaves the site at the southwest property comer, travels west and enters a catch basin on the east side of 112th Avenue South. The flow then travels west under 1121h · A venue South and enters Ruddell' s Pond. From Ruddell' s Pond, flow travels via piped conveyance northwest through the Maple Glen subdivision until reaching the Maple Glen Regional Pond. At most, a half-acre of upstream flow enters the site from the east. 4. The downstream drainage path has had historical flooding and conveyance problems. In I 998. Capital Improvement Project (CIP) #OAI595 was constructed to increase the volume ofRuddell's and Maple Glen Regional Ponds by 25% and 300%, respectively. No drainage complaints have been recorded since the ponds ® . • I I I I I I I I I I I I I I I I I I I .,, .. (), ' ' Larson Parke September 28, 1999 Page 2 of3 and pipes have been upsized. Despite the recent improvemenis to the do~tream conveyance and retention ponds to reduce the downstream conveyance restriction, a Phase II CIP has been defined to upgrade part of the conveyance system upstream of Ruddell's Pond. It is believed that the Phase II project will complete the improvements needed to fully remedy thetfooditig problem in the local vicinity. 5. The proposal is to collect most runoff from the project site and direct it to a single detention and water quality facility located in the southwest comer of the site. The allowed release would then be diverted from its natural discharge location and utilize a drainage easement that travels west from the northwest comer of the site to 1,12'h Avenue SE and then south to the catch basin that allows flows to enter Ruddell' s Pond.· Flows realign to their natural discharge path when they enter this catch basin. Nuisance flows to the parcels west of the site would be eliminated. 6. The applicant's engineer has already explored an alternate route suggested by. the DDES adjustment committee for released flows to bypass'Ruddell's Pond.and enter the drainage system on SE 183rd Court. The applicant's engineer.believes that.this alternative route also has conveyance· restrictions that would require an everi greater amount of improvements to correct. If the applicant's suggestion of crossing under I 12th Avenue SE is utilized, then the existing pipe capacity would be evaluated for . the additional JOO-year, developed, undetained.flows. · . . ·' 7. Despite the recent pond and conveyance upgrades through CIP #OAI 595, there remains concern for the capacity of the downstream system beyond the Meadow Glen Regional pond. Because of these concerns, the applicant is offering to increase the flow control standard used for the site from Level One to Level Two.· However, this suggestion assumes the completion of the Phase II CIP to rid the local vicinity ofit,s flooding problem. Because of the potential timing problem between . plat development and Phase II CIP improvements, other options exisL The applicant could provide Level Three Flow Control on-site and ignore downstream problems. The applicant could also provide some or all of the improvements defined by the Phase II CIP. The applicant could also contribute to the Phase II CIP. 8. No decorative ponds or shallow wells would be affected by the proposed diversion .. 9. A consolidation of facilities for the proposed subdivision will be II!ore economical in long term maintenance. Based on these findings, we hereby approve this adjustment to allow the diversion of released flows around the downstream lots through piped conveyance with the following conditions: 1. The release rates for the detention facility will be based on the land naturally draining from the site in all directions. The allowed release rate will be reduced by l ' ® I I I I I I :I ' ' ii I I I I I I I I I I I / .-, ·.. ~ j , · .. :-'·'r'.arson Parke '"'· September 28, 1999 Page 3 of3 any undetained flows that would bypass the proposed subdivision drainage,: facilities. 2. The volume for the detention facility wili be b~ed on all flows dir~ted tci the''. ,. · .. facility at full development under current zoning. The detention volume will be sized using the methodology of the 1998 KCSWDM imposed through plat conditions. A volumetric factor of safety or'between 10 and ?O'percent shall be applied. The design Technical Information Report shall state 'the factor of safety selected and the basis of that determination. 3. Water quality facilities must be sizeg based on the entire proposed subdivision . draining to the facilities including any required frontage improvements;. . . . ' . . . -·. . 4. AIi onsite ~~ ~ff~ite drainag~ facilitie~ mii§tbe loc\ited in a' publi~;right~f~;aj, oi storm drainage tract dedicated to King County. ' . . . 5. Conveyance in a closed pipe system for the diversion route must be in accordance with Core Requirement #4. · 6. Additional storm drainage requirements identified by SEP A or the plat hearing · review will apply to this project. If you have any further.questions regarding the SWM'variance or the design requirements, · please contact Mark Bergam at (206) 296-7270 or Randall Parsons at (206) 296-7207. Sincerely, Site Engineering and Planning Supervisor Building Services Division · cc: Curt Crawford, P.E., Supervising Engineer, Local Drainage Services, KCDNR Randall Parsons, P.E., Senior Engineer, Engineering Review Section, LUSD · Bruce Whittaker, P.E., Senior Engineer, Engineering Review Section, LUSD Keri Akers, Planner II, Current Planning Section, LUSD Mark Bergam, P.E., Engineer, Engineering Review Section; LUSD ·, ® I I I I I I I I I I I I I I I I I ,1 I ® Date of Issuance: King Count: Department of Devel, Main Plat File LUSD/CPLN State Environmental Policy Act (SEPA) Determination Of N onsignificance for Larson Parke (DDES File No.,L99P0003) October S, 1999 DDES staff Project: Subdivision of2.06 acres into 14 single-family residential Jots,· including recreation and stormwater facilities, Location: King County Permits: SEPAJP!at Contact: Proponent: Zoning: Community Plan: Drainage Snbbasin: Sectionrrownship/Range: Notes: North of the existing stubbed portion of l 14mAvenue SE; east of 112th Avenue SE. Access will be from 114th Avenue SE. . · . . . · . .f' <1fec,\ df. 0 8'1;oo •W'iO : Formal Plat (L99POOQ3); Drainage Variance (L99V0343) Keri Akers, Planner (206) 296-6758 M. Burnett Larson 26207 Woodland Way South Kent, WA 98031 (ZS',) 115'2 • fb9D R·8 (8 residential units/acre) · Soos Creek Panther Creek/Black River NE 32-23-05 A. · This finding is based on review of the project site plan dated July 28, 1999, environmental checklist dated February 23, 1999, and other documents in the file. ·,. . . B. Issuance of this threshold determination does not constitute approvp.l 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. Threshold Determination The responsible official finds that the above described proposal does not pose a probable significant adverse impact to the environment iVIJ-1.1 N fl U:· CUr", cd Wd0s:c0 000c 0~ ·~ew 'ON Xtl.cl I I I I I I I I I I I I I I I I I I I Larson Parke/L99P0003 October 5, 1999 Page2 This finding is made pursuantto RCW 43.21C, KCC 20.44 and WAC 197-ll aft~ueviewing 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 th_e requirements for environmental ·analysis, protection, and mitigation measures have been adequately addressed in the develop.ment regulations and· comprehensive plan adopted under chapter 36.70A RCW, and in other applicable iocal, state, or federal laws or rules, as provided by RCW 43.2 lC.240 and WAC 197-11-158. Our agency will not require any additional mitigation measures under SEPA. Comments and Appeals Written comments or any appeal of this threshold determination must be received by King Co\,!Ilty's Land Use Services Division prior to 4:30 PM, October 22, 1999. 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. Fajlure to. meet these requirements may result in dismissal of the appeal. · · Comment/appeal deadline: 4:30 PM on October 22, 1999 Appeal filing fee: $125 check or money order made ·out to the King Comity Office of Finance Address for comment/appeal: I<ing County Land Use Services Division 900 Oakesdale Avenue SW · Renton, WA 98055~12!9 ATTN: Current Planning Section Responsible Official: ~ 6~ Oc..~/, IT"i) Greg Borba, Current Planning Supervisor Date Signed Current Planning Section Land Use Services Division Date Mailed: October 5, 1999 SEP:\ Dcte:n:iin3riori.J~ Jr},1199 de [d Wd0S:c0 000c 0i ·~ew 'ON Xtl.cl ·, @ I !1 I I ;I I I I I I I I Dev. Cond. Query Result -DDES, King County Washington ' Page 1 of7 (® King County, Washington I NEWS SERVICES SEARCH • COMMENTS Development Condition Query Results Post-Conversion Condition: S0-220 Effective:August18, 1997. Ammended by Ord. 13576, 7122199, removed a,:ea now covered by NS~P23. Description Significant Trees SDO Development Condition Text Significant Trees. A. The purpose of the significant trees special district overlay is to provide a means to designate areas losing their natural vegetation that characterizes their community and receiving the accompanying impacts from .increased stormwater runoff and decreased wildlife habitat. This district overlay limits removal of significant trees in these urbanizing areas to reduce visual impacts of development and maintain a portion of the natural vegetation and soils characteristic of the Pacific Northwest. B. The following development standards shall be applied to all residential, commercial (including golf courses), industrial or institutional development proposals located within a significant tree district overlay: 1. Significant tree·retention rates. Except when replacement trees are used as provided in subsection 8.5, significant trees defined pursuant to K.C.C. 21A.06 shall be at a minimum retained as follows: · a. Exclusive of the area required for site access by vehicles, .pedestrians, or utility infrastructure, significant trees shall be retained within required·perimeter landscape areas at the following rates: · (1) One hu_ndred percent for the interior perimeters. (2) Seventy-five percent for the street perimeter, provided that this standard may be reduced to 50 percent for retail commercial developments if: (a). the combined landscaping and tree retention requirement is shown by the http://www6.metrokc.gov/ddes/c_cur.cfin 08/17/2000 @ I :1 :1 :1 ii ll i ti ii \1 I I I I I I I I I I Dev. Cond. Query Result -DDES, King County Washington Page2 of? applicant to.result in: i. the loss of the line-of-sight necessary for identification of the retail commercial development; and ii. a vegetative buffer exceeding the screening characteristics. of a Type Ill landscape screen; or (b) The average width of the street perimeter la~dscape area ii-increased bY; 50 percent, provided that within the additional landscape area, significant trees are- retained at the rate consistent with subsection c; ' b. If any portion of the lot contains erosion hazards, significant trees locate.d ·in·the interior of separate lots, including sensitive areas or their buffers, shall be retained in single detached dwelling development at the rate of 20 trees per acre or ten percent of such trees, whichever is greater; c. Significant trees located in the interior of the development proposal,· including sensitive areas or their buffers, shall be retained in(a residential subdivision at the rate of 20 trees per acre or ten percent of such trees, whichever is greater; d. Significant trees located in the interior of the development proposal,· excluding · sensitive areas or their buffers, shall be retained in an apartment or townhouse development at the rate of 20 trees per acre or ten percent of such trees. whichever is greater; e. Significant trees located in the interior of the .development proposal, excluding sensitive areas or their buffers, shall be retained 'in commercial or industrial '. ': . development at a rate of ten trees per .acre or'five percent of siJfh trees, whichever is greater; · · · ···· ····.·· f. Significant trees located in the interior of the development proposal, excluding sensitive areas or their buffers and areas designated for sport fields, playfields or other recreational facilities, shall be retained in institutional developments at a rate of ten trees per acre or five percent of such trees, whichever is greater; g. Utility developments and mineral extraction operations shall' be exempt from the significant tree retention requirements of this section; and · h. Project sites with 25 percent or greater of the total gross site area in sensitive areas, sensitive area buffers and other areas to be left undisturbed such as wildlife corridors, shall be exempt from the significant tree retention requirements of this chapter; 2. Retention plan. The applicant shall submit tree retention plans as follows: a. A significant tree inventory shall be submitted for review prior to or with submittal of development permit applications. The.tree inventory may be conducted by any. method that reflects general locations, ·numbers and grouping.of significant trees on-· http://www6.metrokc.gov/ddes/c _ cur.cfin 08/17/2000 @ I I I I I I I I I I I I I I I I I I I Dev. Cond. Query Result -DDES, King County Washington Page3 of7 site; and b. A detailed tree retention plan shall be submitted for review pric;>r to or with submittal of grading permit applications or other permit applications incorporating grading plans. This plan shall identify the exact location, size, species, and condition of the significant trees proposed to be retained, transplanted or replaced in order to comply with this chapter; 3. The retention requirements shall be met as follows: a. Except as provided in subsection b, the applicant shall determine that the final tree retention plan does not include significant trees unable to survive more than ten years after the date of project completion due to: ( 1) Damage or disease; (2) Safety hazards due to potential root, trunk or primary limb failure; · (3) Windfall; or (4) Age in relation to the normal lifespan of the tree species; b. At the discretion of the county, damaged or diseased or standing dead trees, not classified as a danger tree, may be counted toward the significant tree requirement if demonstrated that such trees will provide important wildlife habitat; c. A significant tree may be credited as two trees when it meets one or more of the following characteristics: · ( 1 ) The tree is 18 inches or greater in diameter; (2) The tree is located in a grouping of at least five trees with canopies that touch or overlap; (3) The tree provides energy savings through winter wind protection or summer shading as a result of its location relative to buildings; (4) The tree belongs to a unique or unusual species;· (5) The tree is located within 25 feet of any sensitive area or required sensitive area buffers; or (6) The tree is listed on a historical register; and d. The department shall, pursuant to KC.C. 2.98, develop and maintain ari advisory listing of trees recommended for retention. Such list shafJ describe their general characteristics and suitability, and provide guidelines for their retention; 4. Protection. To provide the best protection for significant trees designated for http://www6.metrokc.gov/ddes/c _ cur.cfin 08/! 7 /2000 I I I I I I I I I I I I I I I I I I I Dev. Cond. Query Result -DDES, King County Washington Page4of7 retention, the development shall comply with the following: a. No tree removal for a project action shall be allowed prior to the county approval of a grading permit consistent with tree retention and landscape plans; b. Prior to clearing for a project action, trees to be retained shall be flagged; c. Prior to grading for a project action and throughout construction, a temporary · chainlink or plastic net fence shall be used to identify the protected area of any significant tree designated for retention. The height of such fencing shall be adjusted according to the topographic and vegetative conditions of the site to provide clear visual delineation of the protected area. The size of protected area around the tree shall be equal to one foot diameter for each inch of tree trunk diameter measured four feet above the ground; and d. At no time during and after construction shall the following be permitted within the area described in subsection c: (1) Impervious surfaces; fill, excavation, or storage of construction materials; or (2) Grade level changes, except in limited circumstances where proposed improvements using permeable materials are determined by an arborist to be non- detrimental to the trees root system; and e. Alternative or additional protection methods may proposed and be used if determined by the director to provide equal or greater protection for trees designated for retention; 5. Plan modifications and tree replacement are permitted as follows: a. Any significant tree in the interior may be replaced by another.significant tree in the interior; b. If the required number of significant trees cannot be retained, then non-significant sized trees may be retained or new trees may be planted to meet significant tree requirements as follows, provided that the reason for the purpose of.this subsection; the significant tree to be replaced by the new or existing replacement tree is assigned a diameter of 12 inches: (1) When using replacement trees measuring three inches in diameter or greater (as measured by caliper), one-half inch diameter of replacement tree shall be provided for every one inch diameter of significant tree to be replaced; and (2) When using replacement trees measuring less than three inches in diameter (as measured by caliper), one inch diameter of replacement tree shall be provided for every one inch diameter of significant tree to be replaced; and c. An approved tree retention plan shall be modified to reflect any changes made pursuant to subsection a and b: and http://www6.metrokc.gov/ddes/c _ cur.cfm 08/17/2000 ~ ~ I I I I I I I I I I I I I I I I I I I Dev. Cond. Query Result -DDES, King County Washington Page 5 of7 6. Maintenance. The following provisions apply to significant trees where applicable: · a. All significant trees shall be maintained for the life of the project; b. All significant trees shall be pruned and trimmed as necessary to maintain a healthy growing condition or to prevent primary limb failure. This requirement shall not be interpreted to allow: (1) Topping of primary stems; (2) Pruning that results in the _loss of 20 percent of vegetative mass, and (3) Cutting of major roots, except in preparation for transplantation or as deemed necessary and/or acceptable by a certified arborist; and c. With the exception of dead, diseased or damaged trees specifically retained to provide wildlife habitat; other dead, diseased, damaged or stolen plantings shall be replaced within three months or during the next planting season if the loss does not occur in a ·planting season. C. The development standards set forth in paragraph B shall not be applied to institutional development proposals that consist of one or more of the following uses: 1. Government services listed in K.C.C. 21A.08.060, 2. Educational services listed in K.C.C. 21A.08.050; 3. Parks as listed in K.C.C. 21A.08.040 when located adjacent to an existing or proposed school, or 4. Libraries listed in K.C.C. 21A.08.040. Ordinance 12823 Effective Date August 18, 1997 Changes Ammended by Ord. 13576, 7/22/99, removed area.now covered by NS~P23 View Map(s) for S0-220. (Click on a map name in the list) Note: If there are more than one map listed below, there may be a map file http://www6.metrokc.gov/ddes/c _ cur.cfm 08/l 7 /2000 /.?\ ~ I I I I I I I I I I I I I I I I I I I Dev. Cond. Query Result -DDES, King County Washington ending with a "_x" which provides an index for the remainder of the maps. de so-220 1_JJ;Llgg de so-220 10 18.jpg de so-220 11 18.jpg de so-220 12 18.jpg de so-220 13 18.jpg de so-220 14 18.jgg de so~220 15 18.jpg de so-220 16 18.jpg de so-220 17 18.jpg de so-220 18 18.jpg de so-220 2 18.jpg de so-220 3 18.jpq de so-220 4 18.jpg de so-220 5 18.jpg de so-220 6 18.jpg de so-220 7 18.jpg de so-220 8 18.jQO de so-220 9 18.jQO de so-220 X.jpg Page 6 of7 Pre-Conversion Development Conditions Associated with the Above Condition There are 2 Pre-Conversion Development Conditions associated with S0-220. Use the links below to reference them on another page. · Pre-Conversion Equivalent http://www6.metrokc.gov/ddes/c _ cur.cfin 08/17/2000 /.'.7l ~ I I I I I I I I I I I I I I I I I I I Dev. Cond. Query Result -DDES, King County Washington Page 7 of7 NSP-P4 SCP-P7 Back to Code List I Updated: December 29, 1998 King County I ODES Page I DDES/GIS Page I New Query I News I Services I Comments I Search Links to external sites do not constitute endorsements by King County. By visiting this and other King County web pages, you expressly agree to be bound by terms and conditions of the site. The details. http://www6.metrokc.gov/ddes/c _ cur.cfm 08/17/2~ ® l I I I I I I I I I I I I I I I I I I I King county Code Section 16.82.150D D. Construction·projects can be a significant contributor of pollution to streams and wetlands. Therefore, from October 1 through March 31, in the Bear Creek Community Planning Area, the Northshore Community Planning Area, the E~st Sammamish Community Planning Area and the Soos Creek. and Hylebos Creek basins: l.Clearing and grading shall only be permitted if shown to the satisfaction of the director that silt-laden runoff exceeding standards in the King County Surface Water Design Manual will be prevented from leaving the construction site through a combination of the following: a. site conditions including vegetative coverage, slope, soil type and proximity to receiving waters; b. limitations on activities and the extent of disturbed areas; and c. proposed erosion and sedimentation control measures. 2. The director shall set forth. in writing the basis for approval or denial of clearing or grading during this period. 3. Clearing and grading will be allowed only if there is installation and maintenance of an erosion and sedimentation control plan approved by the department which shall define any limits on clearing and grading or specific erosion and sediment control measures required during this period. Alternate best management practices may be approved or required on-site by the inspector. 4. If, during the course of construction, silt-laden runoff exceeding standards in the King County Surface Water Design Manual leaves the construction site or if clearing and grading limits or erosion and sediment control measures shown in the approved plan are not maintained, a notice of violation shall be issued. 5. If the erosion and sediment control problem defined in the violation is not adequately repaired within twenty-four hours of. t.he. notice of violation, then a notice and order may be issued by the inspector to install adequate erosion and sediment control measures to stop silt-laden runoff from leaving the site. The notice and order may also: requir.e. the contractor to discontinue any further clearing or grading, except fo~ erosion and sediment control maintenance and repair, until the. following March 31. 6. The following activities are exempt from the seasonal clearing and grading requirements of this subsection: · a. Routine maintenance and necessary repair of e.ro:;;i_on· and. sediment control facilities; b. Routine maintenance of public facilities or.exis~ing utility structures as provided by K.C.C. 21A.24.050B; c. Activities where there is one hundred percent infiltration of surface water runoff within the site in approved and in.stalled eros,ion and sedimentation control facilities; ., .. d. Typical landscaping activities of existing single. family residences that do not require a permit; e. Class I, II III and IV Special forest practices;· f. Mineral extraction activities on sites wit_h approved permits;. and g. Public agency response to emergencies that threaten the public health safety and welfare. (Ord. 13190 § 5, 1998: Ord. 12822 § 4, 1997: Ord. 12380 § 7, 1996: Ord. 12016 § 3, 1995: Ord. 12015 § 3, 1995: Ord. 11886 § 3, 1995: Ord. 11618 § 1, 1994: Ord. 9614 § 103, 1990). @ -----------·-~ I I RESPONSE TO PLAT CONDITIONS I 1. All platting provisions of Title 19 of the King County Code have been met. I 2. All persons having an ownership interest will sign the final plat. 3. The plat meets the requirements of the R-8 Zoning classification. I 4. The Applicant will obtain King County Health Department approval. I 5. All roads have been designed in accordance with King County Road Standards. 6. The Applicant shall obtain approval of the King County Fire Protection Engineer. I 7. A. The plans have been prepared in accordance with King County Code 9.04 and the requirements of the Surface Water Management Division. I B. Notes are shown on Sheet 10. C. The "Building Downspout Note" will be shown on the Plat. I 8. The engineering plans incorporate all of the conditions stated in Drainage Adjustment L99V0343. A 15.0% volumetric factor of safety has been provided in the storm water detention storage volume. I 9. The storm drainage system is designed to meet KCRTS Level 3 flow control. I 10. The plat has been designed to meet King County Road 'Standards and includes the following improvements: · A Southeast l 83'd Court is improved to the urban minor access road· I standard. 24 feet of pavement is provided, with concrete curb, gutter and walks. B. The west right-of-way line for the north extension of 114th Avenue Southeast has been extended along SE 183ro Court to the north property line of the I site. This alignmenfwiU provide adequate future access. C. Tract B has been improved for access and dedicated to King · I County with access easements for lots 12, 13, and 14. D. A Variance for Tract B has been granted. 11. Note 15 Sheet IO prohibits clearing and grading on the site between October 1 I and March 31. I 12. All utilities within the proposed rights of way will be included in a franchise agreement approved by the County prior to fmal plat recording. I 13. The Applicant will pay the MPS fee and administration fee. 14. Recreational facilities will be provided on Tract A and an overall conceptual I recreation space plan will be provided by the Applicant. A detailed recreation I Job# 99330 Response to Pia! Conditions rm ------ I I I I I I I I I I I I I I I I I I I 15. 16. 17. space plan will be submitted to DDES and King County Parks. A performance bond for recreation space improvements will be provided by the Applicant. The required recreational space is 390 sf/units= (390*14)=5,460 sf required< 6,042sf provided. A homeowners association will be established by the Applicant. A significant tree inventory is included and shown on Sheet 9 along with the Tree Retention Plan. New trees will be planted in the Recreational Space Tract. The Applicant agrees pay the school impact fees. RESPONSE TO VARIANCE LOOV0092 A driveway curb drop per KCRS Dwg. 3-005 will be provided. See plans. Job # 99330 Re~pon"!' Ill Pin! \';(lntliliem I I •• I I I I I I I I I I I I I I I I RESPONSE TO DRAINAGE VARIANCE L99V0343 1. 2. 3. 4. 5. 6. All naturally occurring flows are routed through the detention pond. A volumetric factor of safety of 15.0% has been included in the pond volume. The water quality facility (wetpond) is sized for the developed condition. All storm drainage facilities are located in the ROW or Tract. The piped diversion route is designed to pass the I OOyear flow. The Hearings Examiner's Conditions are addressed above. There were no SEPA Determination conditions that apply. Job # 99330 Response to Plat Conditions © --------- I I I I I I I SECTION III I OFF-SITE ANALYSIS I I I I I ' •• •· ·-<. I I I I I . I I I I I I I I I I I I I I I I I I I I DOWNSTREAM ANALYSIS FOR LARSON PLAT CLIENT: Bernie Larson. 26207 Woodland Way So. Kent, WA98031 Phone: 253.852.4680 PREPARED BY: Daley-Morrow-Poblete, Inc. 726 Auburn Way N Auburn, WA 99350 Phone: (253) 333-2200 PROJECT: 99330 DATE: December 1998 REVISED: July 21, 1999 (j) I I I I I I I I I I I I I I I I I I I TASK 1: TASK2: TASKJ: TASK4: TABLE OF CONTENTS STUDY AREA DEFINITION AND MAPS RESOURCE REVIEW FIELD INSPECTION DRAINAGE SYSTEM DESCRIPTION AND PROBLEM SCREENING TASKS: MITIGATION APPENDIX I: Copy of King County Drainage Complaint Information Copy of Color GIS Map Showing Properties With Drainage Problems EXHIBIT A: D.M.P., Inc. Field Survey of Existing Conditions For The Site EXHIBIT B: Topographic Map ® I I I I I I I I I I I I I I I I I I I TASK 1: STUDY AREA DEFINITION The Larson property is within a portion of the Southeast quarter, of the Northeast quarter of Section 32, Township 23 North, Range 5 East, Willamette Meridian, King County Washington. The property is kn~wn as Lot 4 of Bill Ruth Addition. The site is located to the north of the Recorded Plat of Emerald Glen. Emerald Glen has provided a stub road to the site at the northern extension of 1141h Ave. South. The Larson property consists of approximately 2.06 acres per the assessor's map. There is an existing residence within the central portion of the site that will be retained. The remainder of the site is presently undeveloped and is mostly covered with pasture grass and a sparse scattering of shrubs and trees native to the northwest. The existing ground slopes from the northeast corner of the site to the low point at the southwest corner of the site. There is an area of approximately 0.50 acres, identified during our site visit that contributes to the flows through the site. (This area was not identified in a previous study by R. W. Beck, which is on file with King County). The field survey of the existing condition for the site is included in this report as Exhibit A. In the existing condition surface stormwater runoff, generally flows to the southwest to be intercepted by the existing drainage system along the eastern side of 112'h Ave. SE. The site is within the Panther Creek sub-basin of the Black River Drainage sub-basin of the Green River basin. At the present time, it is proposed to develop the site into 14 lots. The structures are to be a combination of Townhouses and single family detached structures. The Larson property is within a sub-basin drainage area that is within the basin boundary of a Study prepared by R. W. Beck ( on file with King County) that resulted in a King County C.I.P. The C.I.P. # is OA1595. The C.I.P. was constructed during the summer/fall of 1998. A copy of a map, taken from the R. W. Beck study, is included in this report as Exhibit B. This exhibit shows the project site in relation to the study basin. The lowest portion of the basin is approximately 2000 feet from the site. The site is approximately 1.3% of the basin. The point I-mile from the site is also shown in Exhibit B. A copy of the Thomas Brothers -pages 656 & 686-vicinity.map is included in this section. The site is within page 686 Section El. The flowpath will be within El and DI of page 686, and B7, C7 and D7 of page 656. @ -...... I .. ! a 3S 1cl lSU ""·! lilO.Zl I " § :llS Ar/ i; tlUltl -1 ' , I-IIQ "I ii ~- ~ s • L66t llfJil:1.1.dO)-:Z:.- ----------~ lS AV OOS\ " AV • ~ ;; ~' ~ ~! Hl\>8 A~ lS II "" '---'-S8:c9'-' m ----·-·-·- ------• • • • • • ·"-" '""' I I I I I I I I I I I I I I I I I I TASK 2: RESOURCE REVIEW The following is a discussion of the resources that have been reviewed in the preparation of this Downstream Analysis: 1. King County Basin Reconnaissance Summary Reports The site is within the Panther Creek sub-basin of the Black River Drainage Basin. King County has recently completed a C.I.P. that consisted of a reconstruction of the "D- 90914 Rudells" detention facility and the "Maple Glen Regional Pond. As a result, the King County Basin Reconnaissance Reports were not used in this report. 2. Flood plain/ floodway (FEMA) Maps The site is not within a 100-yr floodplain. 3. Sensitive Areas Folio Copies of the Streams, Wetlands, and Erosion Hazard portions of the Sensitive areas Folio (pages 5) showing the location of the site are included within this section. There are no King County mapped sensitive areas within or immediately adjacent to the site. 4. Drainage Investigation Information A chronological printout of historic drainage complaints made to the County within the area on grids DI & El of page 686, and B7, C7 and D7 of page 656 of the Thomas Guide is provided-in Appendix I. This covers an area beyond l mile-downstream from the project site. This. information was obtained from King County DNR Drainage Investigations. The contact person was Dave Hancock@296-8230. Also included.is a copy of the King County GIS ·color printout for the site that shows the properties.(outlined-in orange) where there have been dniinage c9mpfaints in the past. Mt. Hancock was contacted by telephone concerning the drainage complaints within the do"'!lst.ream area qfthe proposed Larson site: Mr. ·Hancock stated that there is a 15-year history of drainage problems within the downstream portion of the Larson property. King · County W.A.L.R.D. has recently conducted extensive studies.within the area, which resulted in the reconstruction of the "Rudells" and "Maple Glen" detention facilities. Drainage complaints in.the area were made prior to completion of.the reconstruction of the Ruddell's · . and ?vfuple Glen detention facilities. I I I I I I I I I I I I •• I I I I I I 5. King County Soils Survey Maps A copy of a portion of Sheet 11 of the King County Soils Survey Map is included. The site is underlain with Alderwood (AgB) soils. 6. Wetlands Inventory Maps The wetlands page of the folio does not show a King County Inventoried wetland within the site. 7. Review ofD.D.E.S. File for Toth Estates ( Recorded Plat of Emerald Glen) The D.D.E.S. file for "Toth Estates" was reviewed as a part of this report. Toth Estates is located directly to the south of the Larson site and is a part of the same drainage basin. Toth Estates has been recorded as Emerald Glen. Currently houses are being constructed. Toth Estates is provided with a sophisticated infiltration system that infiltrates stormwater into a series of 36" diameter dry-wells that have been drilled to a depth of approximately 30'. The current infiltration design for Toth Estate is a reconstruction of the original infiltration facility that failed shortly after construction. The Level II Downstream analysis for Toth Estates has been obtained and reviewed. However, since the construction of Toth Estates, King County has conducted additional studies within the basin that resulted in the reconstruction of the "Rudell" and Maple Glen" detention facilities. As a result, the Toth Estates Level II has become obsolete. The information within the Toth Estates file that may be relevant to the Larson project is the realization that any project that contributes stormwater runoff to the "Rudell" pond and beyond has the potential of adding to the historic fliioding problems within the downstream system. The SEPA declaration for the Toth Estates project was appealed by the downstream property owners. 8. Conversations with W.A.L.R.D. Staff concerning C.I.P. within the Downstream System · During the initial field i~vestigatio!) for this report, it became obvious that since King C.ounty: had recently reconstructed two Detention Facilities, the best information is to be found at W.A.L.R.D. The Key Players are as foll9ws: a. John Abdalkhani: . Mr:Abdalkhani.was the Design Engineer for the C.l.P. #OA1595. Mr.Abdalkhani. currently works for the wastewater section and can be contacted at (206) 263-4447. Mr. ·· Abdalkhani was contacted in an effort to locate the C.I.P, file for. the basin. When Mr.Abdalkhani left W.A.L.R.D., the files for the project remained in his old office. In a telephone conversation with Mr.Abdalkhani, the following information was obtained: 'I I I I I I I I I I ... I I ..• ';, •, . I I I I I I I. 11. Ill. R. W. Beck prepared a study for the entire basin that contributes runoff to the "Maple Glen Regional Pond". The study contains good information concerning the definition of the Basin and Sub-basins. The Larson Site is within the study definition area. Volume I and II of the R.W. Beck study is on file with King County. Mr. Abdalkhani estimates that after the completion of the C.I.P., the lower portion of the basin will continue to experience flooding during storm events greater than the 10-yr storm. We believe this estimate to be very conservative. If this assessment were true, more flooding should have been experienced in the area. Mr. Abdalkhani analyzed the basin independently using the hydraulic models "Extran" and "KCRTS". The same basin areas used in the R.W. Beck study was used by Mr. Abdalkhani in his analysis. This report is on file with King County. We have reviewed the report prepared by Mr. Abdalkhani. The report contains generation of the Time Series for the different basins. b. Mike Tseng: Mr. Tseng was the Project Manager for the "Maple Glen/Ruddells" C.I.P. Mr. Tseng can be contacted at (206) 296-8319. Mr. Tseng is currently the contact person for all inquiries concerning the C.I.P. and has committed to making the project files available for review.· Mr. Tseng has indicated that any future development within the basin needs to consider the reconstruction of the "Ruddells" and "Maple Glen" facilities. c. Fred Bennett: Mr. Bennett is with the construction services, and was involved in the reconstruction of the Ruddell's and Maple Glen facilities. Mr. Bennett assisted us in locating the files left by Mr. Abdalkhani. We visited his office in an effort to.locate additional information as fo how the ponds were resized and how.the new conveyance.facilities were designed. We did not locate any other report except_ for the one p~eviorisly mentioned. Mr. Bennett said that he had spoken to Mf. Abdalkhani abouftlje porids .. From our discussion, we · _· · _understand that the capacity of the two ponds: were rriaximized as much as possible. Mr Bennett stated that the Ruddell' s pond was increased by about 25 percent, while the Maple Glen pond is approximately 3 times it's former size. Mr. Bennett mentioned that the worst flooding occured on the lot across the street from the Ruddell' s pond, however, this lot has been filled and a ne~ house has been built recently, he did not beheve this new house will be flooded. Mr. Bennett also mentioned that during-the replacement of . ·· the existing pipes, it was d_iscovered that one of the old pipes was collapsed and may have caused some of the problems. Mr. Bennett also stated that there have been no flooding · complaints since the ponds were enlarged. He said that he has gotten complaints due to construction, but did not relate to the capacity of the new drainage facilities. ® f l be- ln- the ms. I .... Streams and 100- Year Floodplains ........... _... Class 2 ~,ith salmonids) ----Class 2 (perennial; salmonid use undetermined) ••••• Class 3 Unclassified Kent '· ',\..·_ .. . ·1 .I. ! ' ,_ ' 5 @ - , an .,t~; P· co oca~ I .. ,. ---- Wetlands ---- -wellanda· OpenWate, Basin Boundaries Sub-basin Boundaries --- Kent -- ) ' / / \ ~----) \ 5 I I .. n· . ;-Ti: V id::V i;__ --~-,,:rr -:. --1..__ r . i :~.-,,. ...... Erosion Hazard Areas Kent .s' r / (;_7'\~·' ·>-:.~ " ... . , 5 -., ~-. a..:..n · .. '!:' . " .··11 .,,: ,, . ' . ' '2 ..• :.•"4' ,. ~ .. .., : ' " " • " ·-·" ., • • ' • ' ' Aa:B. ~ .... --..t~ ·-~ •: =-~~ ,wj::} ~ .. ~-~ ------·~-----------OFF-SITE ANALYSIS DRAINAGE SYSTEM TABLE Surface Water Design Manual, Core Requirement #2 Basin: Subbasln Name: Subbasln Number: I!. tr e DI :,C IJAf?.bG ·. · NO (-0/1.116 '/ANt:£ . 0 I I I A I LOC-AI] ()Y1 . FIJC/t,/"'?. _ _.' . . --- A-B ()I/OU!/ Nl:J . . . We/UD: w/1',.,~s 6,8% . / Tvnvt-& Ft...aw, W/C..(., -1.,crcv · -If ~ cJ,. I'; /. · 0 -zso IVCO/ e None: Nor .PA~ 1/.//2=G!'f_ A12tA 12,-C I 12 11 CMP tz 1'12-r5firz. ,IV "KTIZ&'ll/1 -;. zJ., ' I ,v•t<IC f'ot€!VTIA, L.. '"";:;Jr N,;;-li!.C) 7lJ C . 2So ·.Z/7 ovP/ZFc..<AJ IJ /2€ >UIC-€" fLow 7ffR.ovGH uno A I 'f I CIIYiffZ(} L t'//Zu~ U ;z-,; C-DI Q.1;c""'st7a:,..,qe1:> f>t]Y)D -3 • 8 I/ poK. /C-OT IIAv6o//lE/lIUJ/.,,) c.-ur;-, J)-1: I 2ll II Cpt;-p ,P(ll1D ,4 ou'ni;r. I I Nf:Wt, INST,i/ll {:l) o.S;. 4 -!;11 (/ /( ,v'tr>1c 211-" CP!' P o.sa7. :,/ I I I/ fl II E -!= I N!;WL.'1 /nSmlc..lFP 17 • S'37 F-G 2 (./ I( .C- I( It 1, 2.v ''cPeP v/ /I I 'I G- H-T . 29, <!.,pep .. /1 I !( I ti --J 2,'{ (( cfJ6/ fl I 'I I ,, I -K 11 Gf'eP .: (( I I f I /1 _,V(ilt}l, .. . . ~ ' . J(_-L 3S "X 2. 'I 11 Cfofi,' I/ I 1/ I I) ·A/€1-06'1 IW..4llc'D <?,.fo/. ~273,5-/'{_/'1 @ L Hable.doc 11'2(92 ---·-'-·-·-.::--:·---·-------- @ OFF-SITE ANALYSIS DRAINAGE SYSTEM TABLE •.. •. • '.!;' -,' • ' ·. · Su.rfac;:e,Water Deslg11 Manual, Core Requirement #2 •' Basin:· \7•" . •.. :. ·· s·ubbasiii Nitnie.: i'. -tt.J ]f ">< 2" t ct-1, 11-tJ IJs''x 2,Y'1 1/-o v,)- M<;s s; M. 6 .st. . b Zv,d/ g '77> l,,0/l,'TH l!..,NScJV'1 fl.A X-'-j / P!'fCI{ I I '1.)CTll!/JD T'1~ "f Wt!)€ l< 2· vc,,,p · V66€ Ti - • /v{lyJ £ II - II -,, II - I I - I I - II -,, - {{ I( S7 -22a-' · I/ zw7'-.szz71 /JON/i · % I ,, , I_ 3n1 ~Jso1I tv<mre Cf'YI€ /I 7t fl ,, I/ 'I // // II Subbasln Number: ;tm1& ti I) If I/ II If I/ !, tlMcS J:JICC€a 11~_0'-D ~Q N€W oue-rz.~ IA) fflC-1U17 63 /"./SrA ll,€, · L 1T able.doc 11/2/92 ----· ·-··--·------------ ~ OFF-SITE ANALYSIS DRAINAGE SYSTEM TABLE Surface Water Design Manual, Core Requirement #2 Basin: Subbasin Naine: . , .• ,1• :, /Jc>JV6 I /Vo)/} b // I I( l/__-l: I Y)1Y-'f, 11CMt'~lo,ziv~A:i·~$-JA.H:,l-'t I 1.\~7'---~01 DITCf/ ,. -I 'lc I ' / , {l.'vvrtJeX 2£\'EliPI FUL<., Of-vf:6UJAT'/~1'/ y '33'° -3,71;"o c--i, q JI 1/ II - °G -? I C, 5l 11xt;.'1 11 CHJ"'I oi-z,, I; 61,v/ty <,12,<1~1~& 1~ I .%137801 -?e'IQ1 I O!Tt/-1 1· · V 1 1 , , ~2--CJ q' i.vi~Ex<-'D<!r;i'' Fuvr., of 115beT>:"fltJ',,, -x; ii. )9vo :--Jt\lo /.I I I( If I f/ I 1 11 ?-.. -/ ?JI/ I/ I . }Jci -,, 1) . / / :, ;(Y'J CHP D /LJJl GW/r'Y C(W,~ '-'t,;, ::,9'-lo -'-loo• I-7 lf~ro~ x.-,'/;e-e:-PI · f-u~t.c'--~f v.lfc,€7JIT1M~2-J~J~>-'loc/1 If . 111 (.,n,~ ··/OSTHPl ·si; I.., "1... / I Z.l. fl.P-.·. i>}-.Cl,(2.l)sStn °"' /Z/L QD 1~ 6%'ff060 -S'la, 17-3, ,5~4 ·· 0 · :· , I CIIAftJIVl!l, we.-v.v~Gi1JTW j::t; -1 . . , .. ,!qf%p ~1~/NIJ "'tr,-i_ 8iiosr1 ~ jii,de;:s ·z0 J.'!S"w1/ -S6'lo 1 t}l() ~ l,j'v] EIZ-4-s, !ft-? ILJ-,5 r-, I/ . . . . . I ~AI> C,/?,(hGlAJC, . . L.,. ''/.· I .. . I .... .:,8 C/VJP · -.· · . · · f"' I • s'C tJ,o -5_1rx> RJ;;,o (?--0 ,tD Au6"?-ro av_ e'/?, -ro ff/, ' , . Subbasln Number: 1 M p.,1tvr6N;i.AJC8 Ar vfJbr/U.,9'<.1'1 ,n.; o (11071& II I/ I ii - I I/ I /I , ,t.EAGH 6 S'11tJJG:!T 7D e"tZt,51~ /Z,oAD ()Vt'ill-;'l)f"/Jltv C. · L1Table.doe 11/2/92 I .I I I I I I ·I I I I I I I I I TASK 3: FIELD INSPECTION The Larson site has been field surveyed .. Topographic contours are shown on the existing site plan-Exhibit ,(.There is· a small area to the east and northeast of the Larson site that contributes ; st'omiwater iunoffonto the property. ' . . .· . . . ' . . ' .The site and the downstream system to the "Ruddells" detention facility was walked on December 17, 1998. The neighborhood was driven to roughly identify the basin breaks, and the ·Maple Glen Regional Pond". was observed.-The weather during the site visit was cloudy-and rainy. Stormwaier was observed to be' flowing within the existing curbs, ditches and conveyance along l 12'h Ave. SE. . · · · Ad~itio~al field reconnaissan~e occurred on January 7, 1999: The purpose of this additio~l. field visit was to observe the basin boundary and C.I.P. improvements with respect to the C.LP. Design Plans and the R.W.Be_ck Report. · · . L . Investigation of Reported or Obse~ed Problems During Resource Re~iew · : The site is within a basin that has a history~of drai_nage prob_lems.·1:he "Ruddells" d_etention facility ap~ars to have ho emergency overflow facility due to the fact that the shear gate was installt;:d on: the outlet side of the Type II structure that is provided with a "Bird Cage"·· · · 'overflow. During the site-visit, the shear gate was in the full open position. This concern was discussed with Mr. Tseng. Mr. Tseng indicated that the function of the "Bird Cage" is to provide an overflow in the event that the inlet pipe is obstructed. Mr. Tseng also indicated that the Shear Gates will be located in the proper position once the as-built has been completed. · · · Due to the absence of significant storm water it was not possible to observe any problems in the field. · ' · 2. Location of Existing/Potential Constrictions or Lackofca·oacity in the Existing Drainage System · During a conversation with John Abdalkhani, Mr. Abdalkhani indicated that there is still a capacity problem downstream of the "Maple Glen Regiona!Pond" that will result in . localized flooding within the upstream basin during storm events greater than the I 0-yr storm event. This is a result of the WSDOT requirement that the·CJ.P. cannot increase any stormwater flows across the Benson_ (SR 515), · We believe this assessment to be in error, and that the IOayr·stoim is a very conservative· estimate. During our site visit, we did not identify any problems with the facilities along Benson, except for the discharge to the ditch, which needs to be cleaned. During our discussion with Mr. Bennett, we asked him if he was aware of any problems with the : facilities along Benson. He indicated that he is not aware of any. We believe that the facilities have enough capacity: Our observation is also supported by the findings in the R. W. Beck study. We believe that the reason flows across Benson was not to be increased, is because of the erosion problems further downstream, and not because of capacity. @ j ii • I I I I I I I I I I I I I I I I 3. Identification of Existing/Potential Flooding The Larson Plat downstream basin has a history of flooding, A printout of recent drainage complaints is provided in the Appendix. Both Mr. Abdalkhani and Mr. Tseng have indicated · · ·. that with the completion cf th_e CJP.; localized flooding within the lower portion of the basin . will still occur during storm events greater than the I 0-yr storm events. · . ·, ( @ ----------------------------------~------ I I I I I I I I I I I I I I I I I I I 4. Identification of Existing/Potential Overtopping; Scouring, Bank Sloughing, or Sedimentation Thedownstre~m systt,m fmm l i2'hAve: SE to the "Maple Glen Regional Pond" is within a. closed conveyance system. All of the down$tream conveyance components from the "Ruddells'.' pond to the "Maple Glen Regional Pond" were recently recoristructed (upsized) during tfi~ suinmer/fall 1998. Information concerning the extent of existing/potential overtopping, scciunng, bank sloughing, or sedimentation for the downstream system west of the .Benson is provided ·in Task 2. 5. Identification of Significant Destruction of Aquatic Habitat or Organisms The basin-that contributes stormwater runoff to the "Maple Glen Regional Pond" contains urban residential neighborhoods, most of which were developed prior to the 1990KCSWD ,, . . i Manual. The Larsory site is within a portion of the basin that contains larger lot sizes. All of the historic tributaries west of the Benson·Road have been altered or eliminated in some form in the past. ' 6. Collection of Qualitative Data on Land Use, Impervious Surfaces, Topography, and Soil Types The upstream contributing drainage basin that contributes stormwater to the site is mostly · developed. The soiltype for the majority of the basin is Alderwoo9 (Agb). T!ie topography of the site is shown on the existing condition Exhibit A. Based upon a conversation with Mr. Abdalkani, the RW.' ,Beck report contains accurate information concerning the Basin Definition, and the Sub-basin areas within the area of concern. · ' 7. Collection oflnformation on Pipe Sizes, Channel Cliaracteristics;and Drainage Structures. Due to the fact that King County already has detailed information on Pipe sizes, and Drainage Structures in the file at W.A.L.R.D., no off-site field survey information has been obtained for this report. The design for the conveyance system from the "Ruddells" pond to . t!ie "Maple Glen" pond is on file with King County. . '": . · 8. ·Verification of Tributary Basins ,Based upon a conversation with Mr. Abdalkani, the RW:-Beck report coniains reasonably accurate information concerning the Basin Definition, and·the Subsbasin areas within the· area that contributes stormwater runoff to the "Maple Glen Regional Porid". ., I ·I I I I I I I I I I· I· I I I I I I I 9. Contacting of Neighboring Property Owners No immediate adjacent property owners were contacted during the preparation of this report .. During the January 7, 1999, site visit, a property owner at the south end of 109th Ave SE (Lot _ 15) provided information c9ncern1ng a 43 unit Townhouse project proposed within tax parcel· 322305-9138. This project is within the basin that drains to the "Ruddells" pond. The D.D.E.S. File.# for the proposal is #B98C0083. This is a 5-acre site that will be contributing . developed condition stonnwater runoffto the downstream basin that includes the Larson project. The property owner, Mr. Jerry Huso stated that the property to the south of his house is always wet and during the winter months, and that water occasionally ponds within his · driveway. , This infonnation is provided to alert King County D.D.E:S. that the stonn detention facility within the #B98C0083 proposal needs to be designed so that it does not adversely impact the downstream sys_tem. 10. Documentation of Existing Site Conditions The existing site conditions are documented in this report by_ the field topography, and walking the site. Docume'ntation of the downstream system from the site to the recently reconstructed "Ruddells" Detention facility at the northeast corner of I 12th Ave SE./SE l.84th Pl. is based upon walking the downstream and taking notes· 11. Collection of Quantitative Field Data King County: W.A.L.R.D. collected extensive quantitative field data prior to the reconstruction of"Ruddells & Maple Glen Regional Ponds". The Larson site has been field surveyed. I .',.. I • ' J , I I I I I I I I I I I I I I I I I I TASK 4: DRAINAGE SYSTEM DESCRIPTION AND PROBLEM SCREENING ' . I r. Drainage System' Components . The downstream drainage system components have been field surveyed and are a part of the R.W. Beck Study: This study is on file at W.A.L.R.D. The C.I.P. design plans are also on file with King County. Mr. Tseng indicated that as-built plans have not yet been provided to the county from the contractor. · · 2 .. Existing/Potential Problems During the site visi_t there were no indications of existing problems. During the research portion ofthis·report it.became evident that there.were problems that extend from the area of the "Ruddells" detention' facility all the way down to Panther creek. The properties to the east of Toth Estates experienced flooding when the original infiltration pond failed. The enlargement of the existing detention facilities and the replacement of the conveyance facilities may have provided sufficient capacity to prevent future flooding problems. Mr. . Bennett indicated that the ponds have never been full since they were enlarged. We believe that · the reason why Pond A failed was because of the collapsed pipe, which has been replaced. T_he Off-site Analysis Drainage System Table in Task 2 identifies the areas were potential -problems may occur. @ I I I I I I I I I I I I I I I I I TASKS: MITIGATION The flow·control applications map at the end of the 1998 SWD Manual identifies the area as a . '.'Level l, Flow. Control Art;a": Due t~.th·e e"istence of.k_nown downstream problems, it appears that"a more strict flow control will be required for this project. During the site visit, it appeared that the southern portion of the "Ruddells" detention facility could be enlarged to increase the storage volume of the facility. The design plans for the "Ruddel~s" pond show the top of cut at the southern side of the pond as being at or near the chain link fence. However, field investigation shows that the top of cut is approximately 12' north of the chitin link fence. Therefore it may be possible to increase the_ volume within the "Ruddells". pond. We were previously proposing enlarging the pond as part of the mitigation for the Larson Plat. We are no longer proposing this, however, in lieu of enlarging the existing pond, we are · . proposing to use a more restrictive design criteria for the new pond _with_in the Larson Plat. We believe that the recent upgrade to the existing ponds and conveyance_ facilities provided · sufficient capacity to preverit future flooding to the existing homes. The statement made by Mr. Abdalkhani about flooding in the lower portion of the basin for storms higher than the 10-yr storm; if in-fact true, will be more of a "Conveyance System Nuisance Problem" instead of a ':Severe Flooding Problem". We believe this to be the case since the new pipes will be able to copvey water to Pond B, which is the lowest portion of the Study Basin .. · In the event that Pond B fails, water will pass through the overflow structures and the emergency overflow, which is _ lower than the finished floor elevations of the surrounding houses. Water that overflows the pond will be conveyed either within the existing facilities along Benson, or within the roadway. We therefore believe that no "Severe Flooding Problem" will occur..However, in-order to assure that \Gter in Pond A will not Flood the homes incase of fail tire, ari overflow facility needs to be installed in Pond A. King County W.A.L.RD. should make these modifications.; The erosion problem within the ravine identified in Task 2 ofthis report was also considered in determining the criteria to be used. The project is within the Level 1 Flow Control area, however, because-of the "Conveyance System Problem" and the "Erosion Problem", we are proposed that the facility for Larson Plat be sized using the Level 2 Flow Control Criteria, however the County has determined that a Level 3 Flow Control Cri.teria will be required for this plan. The proposed detention fadlity was sized using the Level 3 Flow control criteria. · · . · · · · · -----, I I I I I I I I I I I I >I I I I I I I I APPENDIX I The items contained within this appe1,1dix are as follows: Copy of King County Drainage Complaint Information Copy of Color GIS Map Showing Properties With Drainage Problems ) ' I I I· I •• I I I I I I I I I I I I I I DEC. 3. 1998 10: 27~ KC ~RD . '{racker Types BCW Business' For Oean Water · .. C · Complaint CL• . Oaim E ER FCC ' -·FCR FCS LS• R RR S1, S2,SN3 ·wQA WQC -WQE- · wQR X Enforcement Enforcement· Review · Commercial Facility Complaint Residential Facility Complaint Storm Facility Complaint . . I;awsuit . Engin~g Review . Facility Engineering Review Engineering Studies Water Quality Site Audit r · · . Water Quality Complaint Water Quality Enforcement·. Water Quality Engineering.Review · ca (response to inquiry) * Subject to Public disclosure requuements 1) Receipt (If written ieqiu,st for documents 2) Review of documents by Prosecuting Attomey's office-·• 3) Approval by Prosecuting Attorney to View/ copy documents I I I I I I I I I I I I I I I I I I I :·~". 30. 1999 1 : _44PM KC WLRD CQIPLN TY NIMBER PE PROBLEM · ADDRESS lYPE OF · PlOBL~ COIIENTS NEIi fH BR --== =-= =--:: =-=--•••--=::::;::;;; a• ~== -~==•~~==== ••-== .. . 10017 . .CARR RD SE DRNG DASIN/CULVERI/OVERFLOII ONTO PROPERTY /74·0D68'C / ?t,-0069 C ,/7"-)100 C /s<-0104 C •. ·32-':'~"5 C /52·0478 c. -1i3-0107 C /84·0104 C ,85•0712 R 86•1110 C 1"/824 17811 12328 9623 10828 s 175 SPRINGBROOI( IIJl S LIGHT STAIJDARI> FALLING DOW!l PLUGED DRAIN/97TH AVE S CARR RP/98T_H AVE SE · 65687 65687 65687 65687 65687 - 65607 97TH AVE s DRNG SE PETROVITS1CY. RD DRNG S 175TH ST EROSION SE 176TH PRNG CULVERT COLLAPSED TH ST/98TH AV S FILL . 65687 17811 97TH AVE · 174iO 98TH AVE 17258 SPIii NGllROOK RD 10017 SE CARR IIJl S7·0S02 X 87-0502 X 17800 Si·C744 C 17600 38·0421 C 17803 86·"421 Sfl 17803 108TH AVE 108TH AVE SE 105TH PLACE . 105TH PLACE 89•0836 SR 112DO SE. 184TH Pl . 89·0836 C 11200 SE 184TH Pl 90-0492 C 17611 · 90·0492 SR 17611 90·0506 C 17611 ?0-0617 CL· 17611 103RD AVE 103RD AVE 103RD AVE 1031lD AVE . ,:;-'.337 C 10810 SE 181ST ST ,, -'. CW C 9623 S 175TH ST -;3-~065 wee -1ms 105TH PL 93·0415 C 17712 98TH AVE 93-0415 RN 17712 98TH AVE 93-0415 MPA 17712 98TH AVE 94:0526 C 17020. 104TH AVE 94•0625 MQC 10545 · 94-0625 \IQE 10545 CARR RD CARR RO ' 94-0799 IIQC 1040/, SE 174TH Sl ;:t.-C$33 C 10406 SE 174H ST 9j·0128 I/QC 17618' 111TH AVE 95·0128 WQE 17618 111TH AVE S FLDG S FLOG sE FLOG To' OOllE EHF .. EROSION CCF# 51'! .1151 OF CIIEEK CHAIOIEL SE EASEKT ~ELIN<IJISH ·:1 RECQOIENP DRNG SE DRNG SE PIPES APPROVAL COMM PERMIT NO Cl!7•0559 SYSTEII a 17803 105TH Pl SE NO PROB SYSTEM SHOULD H',Nl>LE STROMS DRAIIIAGE POND OVERFLOII 90·0709, 1061 DRMG SE FLDG POND OVERFLOW/STANDING lb\l£R CRAVEL FA~ ROAD INTO l'OND/STROH/90·617 .SE FLOODING /EDLUNOCL/SEDDNPROl>&INPHD STORM SE PRNG SILTS AND WATER/STORH/90-0617,1323 SE DRNG .DEBRIS FR~ FRED . NEYER/CL#129D2 CALLED SINIOtOLE IN CORNER Of YARD FLOODING CROSS PIPE SIZE OK , SE WQ09n90 65687 65687 656B7 65687 65607 · 65607 65607 65607 65607 · 65607 65607 65607 65607 656D7 65Go7 65607 65687 65607' S EROSION s. EROSION s EROSIDH EROSION IN PATHER CREEK 656C7 .EROSION IN PATHER CREEK 656C7 . EROSIOII IN PATHER CREEK· PAUE 656C7 NEEDED SE EROSION PERF PIPE ON NEIGH. LOT IS LEAKING SUBSTJCB DUIIPING Oil INTO·CB SUBST/CB DLJl,IPING OIL INTo·ce· 6561>7 · 656D7 . 65607 · POI.LUT~N MAINT OF COMHERCIAL STORM SYS .65607. INFOLTR FLOOOINC OPEN CHANNEL PVT PROP HO . 65607 EASEMENTS SE OlJ!o1PING RESIDENTIAL CAR RErAIR · OIL 65607 D\JliPING SE DUMPING RESIDENTIAL CAR REPAIR ··OIL 65607 DUMPING 95-0468 C 'sE 108TH & 173RD A SE SLIDE 7 NEW R/0 FACILITY SATETY QUESTION 65607 ,5-Q;34 I/OR 10817 SE 1nND ST. MAINT. VEHICLE /MAINT BMPS FOR CoNOOS 65607 'N0.354 P.2/4' ,, I I I I I I I I I I I I I I I I I I I IJN.30.1999 1:45PM ~o-0534 IIDA 10817 SE 1llND ST. 95:0855 C 17418 1'0BTH. AVE 95-0956 BC\I 17620 108TH AVE, 95-1009 BCII )7426 -1D8TH AVE · 95-1080 Cl 10817 SE 172ND ST 9S·1207 IIIIC 10402 SE 174TH ST 96·0009 C '10700 SE 174TH ST· 17418 108TH AVE 96·0438 R 17418 108TH AVE 96-00B NbA 17418 108TH AVE 96·1196 \IQA 17642 ·108TH. AVE 96-1649 C 10700 SE 174TH ST 96-1662 C 17418 108TH AVE _96·1662 R 17418 108TH AVE.· ?6·1662 R 17418 108TH AVE· 0 6·'$12 NOA 1741B 108TH AVE %-2~~ i ·c 17418 108TH 97•1593 C 104l(l( SE 172ND ST 98-0503 CL 172XX _104TH AVE 98·0803 FCC 10900 SE 176TH ST ?S-08'S7 C 17811 97TH AVE 98·0867 R 17811 9nH AVE ' . KC WLRD · . · .. -. MAINT. VEHICLE /HAINT BltPS FOR CONDOS 65607 SE FLOODING BUILDING FLOOOED FROII BLOC® 65607. 0/S SE SITE CON SE CONSULT, 65607 CLAIM , 9JtOKEN IRRIGAUON LINE. PUIIPING . ALLEGED DUMPING INTO, · IUTERMI_TTENT STAM • 656~7 • 65607 656C7 EROSION APPARENT DIRECT DISCHARGE TO 65607 ROAD SE FLOG· OFFSITE FLDII IMPACTING CHURCH 65607 SE FLOG SE FLOG PROPERTY OFFSITE FLDII IMPACTING CHURCH 65607 PROPERTY OFFSITE FLO\/ IIIPACTING CIIURCH. 65607 PROPERTY SE SITE CON _NEED TO IMPLEMENT _BIIPS 65607 65607 ' DRNG DOIINSPOUT LINE M!IINTENACE RESPD!ISIBILIT SE FlDG SE FLDG SE FLDG SE FLOG SE RUWOFF PIPE SH~ET FLDU FROM PARKING SEE 65607 960438 SEE 96·0438: COIIPLAINANT , . WITHDREW CNPLT SEE 96-0433 SEE 96·0438 65607 ~5607 CROONOI.M.TER IMPACT TD PVT PROf' 65607 POSSIBLE UPGRADE OF OJLV BT 6561)7 ROADS SE SIDEWALK SIDEWALK DAMAGE BY KC CREII. .' 65607 . FLOODING .PVT SYS APPARENT DAMAGE OR .65607 BLO~AGE S DRAINAGE OBSTRUCTED OR INADEQUATE DRNG · '656C7 IMP PVT P S DRAINAGE OBSTRUCTED OR INAD~QUATE DRNG 656C7- IMP PVT P . 1 N0.354 P.3/4 I I I I I I I I I I I I I I I I I I I JUN.30.1999 to14PLN TY KU!iBER PE 9,-0529 IIQC: 4300 94 .. 0995 C 18616 96·0104 C 18616 ·, 96•0104 R 18616 1:45PM · PROBLEM ADDRESS TALBOT AD 10211> AVE 102ND AVE 102NZ> AVE 102JID AVE KC WLRD s TYPE OF . PAOE~EH WASHING IXJO!ENTS INFO TO DENTAL OFFICE SE FLOODING OBSTRUCTED FLOW BY fl!EDRICK'S PLACE ??. SE RUll OFF PA I VATE PROf'ERTY INPACTS FRON ADJ DEV -,, .. SE RUI OFF PRIVATE PROPERTY IMPACTS FRON. ADJ DEV NE DUMPING • APPEARS TO BE ACTIVE CLEARING PIIOJ" NEIi Tij BR. 686C1 686C1 686C1 686C1 686C1 97·1239 IIQC 18600 97-1589 FcR . SE 186TN/1D2ND AVE SE MAINT CONCERN RE MAINT RESP WETLAND 686CI ISSUES 98-0~47 FCR 1Q215 SE 186TH St ,· MAINT APPEARS PoND OK NGPE.WILL NOT 686C1 PE CLEARE N0.354 P.4/4 DEC .. 3.1998 10:28AM CXMPUI l! ll!U"8ER Pf · PROBLEM ADDRESS ,· KC lot.RD NEIi TK BR I I I _.:__-;:-,-_:,.. ....... ""---7~~------· -·--.---··===-·--=== ~ / 9Z·0078 C .11ZOIJ sic' TB211> ST I , 9Z·0078 Sit 1121111 SE 18ZIID ST ~·9Z·0D78·lll>A 1lZll8 SE 1B2l1D.ST · ~ 92•0284 CL 1851M, 112TH AYE / 93.0347 C 18618 106TH PUCE ~-D63Z C 111636 106TH PL I "94•0144 C 116TH AVE I ,<J4•067Z IIQC 106'0 sE 180TH ST I '7 94·1016 C nzo.: se 1116TH ST /95-0179 C 111618 , 106TH PL I /'95·D179 R1i '18618 106TH PL I ,05-0200 c .,_95•0712 C 111Z04 1161H AVE 10320 SE 1116TH ST I I c:-95-1004 Bell 10640 SE 180TH Sl ,· 95·1001' -10650 SE 1SDTH ST ,. 95-1DC7 BCI/ iD650 SE 180TH ST >95-1ooa \IOA 1065& se tBDTK ri . 95:IOllll WA 10658. SE 180TH ST .-'95•1008 BCW 1D6511 SE 180TH ST ~96-0173 FCII 11044 186TH ST I /96·0193 fCR SE 194TH PL & 11Z I I I I I I I "7'.96·0311 C 18330 11ZTN AVE ' -96-0454 FCR 18425 112TH AVE -+96•D5n X SE 184TH l 11ZTff , -, 96-0714 Cl ll~ SE 1116TH ST -'? 96·0794 C 11108 5£ 184TH PL ,. ~-0885 CL 11202 S£ 186TH ST •/'16·1378 C 11ZIIS SE 18ZJQ ST /96-17'01 C 11019 SE 186TM ST 96•1951 -1eCl01 10BTM AVE ./96·2071 C 11B2B'SE 180TH ST J96-Z071 R 111128 SE 1SDTM ST -97·0084 FCR 1851)1,-112TH AVE RDDUUIG nlllHNG TO CIP FUXIIING TD C!P SE nomuu. SH l\JDELL·S-STUDY SE. DIUIG POID UIG JI BACICY~ SE DRII& BAIXDRAIN FROM MEIGHIIOR SE DIIIG SE Jlt. HKUP POSS FILLING VIOL/ACT PlAT -NJN; GLEN se '11WE PDLWTAIIT. IN THE DRAINAGE sY$l'8I Oll/Sl'll AllT!klTJVE BMP•S, OJL/SPll AlJTCll)TfVE lflPtS INFO LTt: -1VZ1/94 68601-/,- 61161)1 -1- 686111' i'° 6M01 {, 68601 68601 6¥[1 6!!601 686o1 68601 6861J1 OVEltFUlU PO$SJBLE ll'IERFLOW 0, l/D l'Ollll' se FUXIIING UIICOIITRDLLEli FLOW DYER SIDflWJC 68601 /. / 6116D1 6861)1 / . SE FtOODlNG mNllll!R !NP TO S/11; I/ILL TIE TD DIINSPTS St: DITCM 7$ LACI( OF CDRVETATRCE <* PVT PlOPEIITY PtllDlNG DRNG fR(II APJACEkT LOT !01Ml1SPWTS1l COlmJl. T. cactU'.,T. BCU SlTE CONSUl..TATlotl 686E1 ,., 68601 ,.- 686o1 / 68601 ~ ctlfSULT. 6861>1 ,./ toNSUl T • 686D 1 ./ CXIIISUL T • 6ft6D 1 v CONSULT. . . . 6&f01 ..., SE RID PIIND STORII ~ENT PORD DYERFLW, JlP 68601 ./ IN P110C SE l/D P011D STOIIN EVENT P011D OVEllflllU . SE DllllG APPARENT GROOll1lUATER !!'l'ACl PVT.PROP SE RID POND ~R\&IOELL 'S CIP PtlOJEC.T_ ·: SE RID P011D RUDl>ELS MIO PROJECT , •. MIKE TSENG 'LDG JUl)DELL N>D RID P<lliD PROPERTY Sllli:IN;; tll't·. FAILUltE77 68601 v ! 68601 i,- 6161>1 "+., 686111 -'f . 68601 'lt 68601 ~ l/D PONI> IIUIIDfLL 'S ADD. ·,. ', ~1 DRN1i GllOUllDIIATER PRDII ,COIISTRUCTIOII 68601 1r 'f. ?? Fllll•G CCIOPL RECUESTED INVESfc.8£ CAJICELLED SEI/QR FLOG INADEou•TE CONV(YMCE llffSIT"f FLOW FLDG INADEQUATE tt]IIVEYAICE.OFFSITE FLC\I SE FLDC UJiOER QJNST R/D P0JC> ' 6116D1 68601 686E1 ,/ 686E1 ,/ , 68601 'f,; NCl.732 ,,-; 16rt5 - P.4/S ~!'lo £1,IJ/a, e; t,,C; £!;/JI b5(:, DJi C1~l37 @ -----, ••• ·DEC. 3.1998 10:28AM -" 97-0095 FCR 11202 Si 186TH ST ...... 97-0173 C 18104 1UIITM PL. -97-0334 rt:11 111425 112rN AYE ,.-: 97-0572 CL 1~ 106TH PL . 97-0668. FCR 111425 11ZTH AYE /97-11Z2 FCS IOl!lllt_ SI: 111211D ST ~ 98-0546 C ~ 98-0691 C I I I I I I I I I I I I I I I 10810 SI! 1e211D ST 111424 112TM AYE . ' ' KC 1-LRD FLOG . RUD~EllS Slll>Y PROal.DI, CIP to 686111 Y' BE DONE SE FLDG MELLS FLCltOIIIG 090914 sE RID POIID RID POND IIVERFLIN PIIO'OSEII CIP PllO.IECT · SE D~INAGE BElOII GRADE BAsENEllT ·rllJIX>IIG SE RID POND HISTORICAL l>ltAIIWiE .PRm1.£111-1 ' MIIIT. Rl!QUEST TO -AID MIIITAIN. Fllla>ING SHEET FIJI/ Flllll ROAD NICI! INTEISITY S1 68601 t-. 68601 'Ir 6861)1 686111 :J- NE D~IIIAG£ ADJACENT lllPROVEllENT 1•ACT11G 61161>1 l" YAIID '·· ( _) N0.732 _P.5/S \ UHORMA TION IYSJl:M A98M044 1 ~r ·thp ~TC!>OIJ •pl"jc Index ~-~SlrHts C S-.0 Lllndtildo Ith ~g ;:'~"" so.o Erotion sttHm ~ N 'hJ S>.0 Wohnd D~J'd::n i;;::i WLR D Cr..,.go C°""'olru Po~•· ~~I Mll'llon Hatard ....... ~ W1hnd1 !~Ofl)I. cl En11nur1 • D Sao Sa.re, ><,.Jftr Neas Hg,ly 9.nceptlbl e to Gro.l\d Wot w C N FEMA Cion S.c:'licns t:) FEW. 100-)<. Aoodploln c a .. , 0 !!!!"!!!!!!'--· 400 ,-.ss1 1u t @ ODES 100 FH I Thlt map 11 b11td cr"I a d gl tll d•labue cCfflPltd by King Coo.rty from, vllioly ol scucu. IOng Ccunty umd 1<eept ro 1pcnsllllllly fr, ca,, om n lcns a pot,1 1.icnal 1ct11acy Ther, er, no wvrantles, H:r'HHd er lmc:itlad. - '""' • I .•.. . . .. . . .. II • ........ ...--.......-: ~ .. :/ .. '. . 1, :~ ·1.·a1.11.1.1. .................... ... ' I t ( (' ' ... ... ... • ' \ ( ~ I I I I I I I I I I I ,I I I I I 1· I I .:.,..~ -~--. SECTION IV FLOW CONTROL AND WATER QUALITY FACILITY. . . . ANALYSIS AND DESIGN I I •• I I I I I I I I I I I I I I I I 02/21100 EXISTING SITE HYDROLOGY For: Larson Parke This 2.06 Acre site is situated within the Panther Creek sub-basin of the Black River Drainage sub-basin of the Green River basin. Presently, the site contains an existing residence near the center of the site. The remainder of the site is undeveloped and is covered with pasture grass and a sparse scattering of shrubs and tr~s native to th·e Pacific Northwest. . The ground slopes from the northeast corner of the site at 9.6% +/-to a low point at the southwest comer of the site. There·is a half-acre offsite tributary area to the site. Runoff from the site sheet flows to the southwest to be intercepted by the existing drainage system along. the eastern side of 112th Avenue S.E. The soils on the site are Alderwood Gravelly Sandy Loam (AgB) as classified by the US 5?il Conservation Service. -. As discussed above, the flow from the site discharges to the eastern side of 11 ih Avenue S.E. where· it is collected by the existing drainage system and routed through the "Ruddells" detention pond at the _northwest corner of SE 1841 h Place and 112'h Ave. South. From there the flow is piped on to the "Maple Glen Regional Pond~ to the northwest at the southeast corner of. SE 182nd Street and 1081h. Ave. SE. The "Ruddells" detention pond has experienced flooding in the past as described in the ODES letter.of September 28, 1999 (see Section 2) and the downstream drainage still has limited conveyance. capacity so Level 3 · stormwater control is required. Job # 99330 Existing Site Hydrology (]) I ~~~0 ~ .;:, ... ; ... : : ; ·_.1-:> \' . I -~ ··o· .,· ···.-: . ~ I • •. •••• 0.-·:•o , •0 9 -« _:0<f.,. 1 ·0"· I "~ » . o :t. . 8 I 4Hy·; .·t -i ,_ --~-o'4<f:' .. ·-· .· \2L .. · r ::~:~:, . : ·000.50 •· .. r,1 ' . . I ., . ' ' ., •. ... ' ~,: .,, :,·•c~: \ ,,_ . ~! -<.·~--,. ·.::,. ·_/{_ ' -~ ·'.~: .::· ·;-, ", ,'v ' I . • • •. , • ~ @ \~: .;::;: \ ,;_ .. ' . .. -;;.:· .. 1>"' .. .,;.:· ,. ... '"(,.'.- . ;1· .f. ~ I. . ll I . . ·~) ,., . :Is ,] )I . 'f ' . ' -t . · l, 'J' . I :J j " ,·. j ·:r . ~l •;· -;~~ _:l (§ . ' .. I > .... , ----.i :, .i.< . ( ./ -~ ~ -~ ) . ~.t ' . ·"· . ,e , .· '· .· . ' ' .. l . • . . .. ,. . ' . 'I: . " ,'.,,. (_, l--1 f>l _, \ ,L'~_\2G· I , 02-, ~oa I os 3 " .... 0030 I . r FLOWPATH I I I I . ~~~, ! J l e ' ~ '(,· ~~ .. ).-.~· .,.. * 19 0190 20 0200 - ... -':<>• .. , ' ~:\:-.I u~re.tAM · bA5/tJ ~} /[(! ;.t-b-·-k-• \ ' \ •t-L I /~ . 18 0180 17 0170 J Ii \ 19 0090 ..;( -r -1 ' ' . . : 'rjr:1.··. i ! I :· ' • I -----__ .. _, _,.,__ ___ ~· -*~ H ' :·-·-'·-··: ; · I ; -J ., l ·.:; ,f:Xf{D{'Ju-~o_N~1T10N . ·; DM/N~Et 1MAP/ ' :·1! s. t1 • '·. J.~ ·• , .. ,, -. f 11 -:c-·r-:o' I ~ . •. . ' ---' ,:;;,,..ni..1.,, • -:>< .J . 'G-\:1--. ! • \ • -------1 . g' ::t,; s '\ J j // . ,. ~-·-, :·1 ' / ' . -~/-' ' --. . , • r • t~T U : .. ; . • J.. .•• ®} • ... 1 ,.. '.' I I I I . I I I I I I I I I I I I I I I J. 07/11/00 'EXISTING CONDITION For: Larson Parke . On-Site Area • < Location: The intersection of S.E: 183rd Court and 114th Avenue S.E . Rainfall Region: SEATAC Location Factor: 1.0 Total Site Area= 2.06 Acres Till Forest= 0.38 Acres Till Pasture = 1.52 Acres . \,. Total Impervious Area= 0.16 Acres (Existing Buildings, gravel drives, and AC pavements) Effective Impervious Fraction = 0.5 from Table 3.2.2.E Effective Impervious Area= 0.5 x 0.16 = 0.08 Acres Non Effective Impervious Area= 0.16 -0.08 = 0.08 Acres Total Grass Area (Till Pasture) = 1.52 + 0.08 = 1.60 Acres Off-Site Area (t1i' ~T/2.EA-N) Location: Partial area of adjacent property on east sid~ of the project site Total Area= 0.5 Acres Total Impervious Area= 0.18 Acres Till Pasture = 0.32 Acres Job # 99330 Existing Conditions @ I I I I I I I I I I I I I •• I I I I I Flow Frequency Analysis Time Series File:a:ex-on.tsf Project Location:Sea-Tac ---Annual ·peak Flow Rates--- Flow Rate Rank Time of Peak (CFS) 0.149 2 2/09/01 18:00 0.065 7 1/05/02 16:00 0.141 3 2/28/03 3:00. 0.027 8 8/26/04 2·:00 0.080 6 1/05/05 8:00 0.133 4 1/18/06 16:00 0 .127 . 5 '11/24 /06 4:00 0.258 1 1/09/08 6:00 Computed Peaks EXISTING CONDITION ON,-SITE --'---Flaw ,Frequency Analysis------- -· -Peaks Rank Return Prob (CFS) Period 0.258 1 100.00 0 .. 990 0.149 2 25.00 0. 960. 0.141 3 10.00 0. 900' 0.133 4 5.00 0.800 0.127 5 3.o·o 0.667 0.080 ' I 6 2 .. 00 0.500 0.065 7 1. 30 0.231 0.027 8 1.10 0.091 0.222 50.00 0.980 ·~ ,------- I I I ' I I I I I I I I I I I I I I I I Flow Frequency Analysis Time Series File:a:ex-off.tsf Project. Lo.cation: S~a-Tac. ---Annual Peak Flow Rates-:-- Flow Rate Rank Time of Peak (CFS) ·0.06.1 5 2/09/01 2:00· 0.047 7 1/05/02 16:00 0.071 2 2/27/03 7:00 0.046 8 8/26/04 '2:00 0.055 6 10/28/04 16:00 0.066 4 1/18/06 16:00 0.066 3 10/26/06 0:00 0.124 l. 1/09/08 6:00 .Computed Peaks ,. ·-,;:, -----Flow --Peaks (CFS) 0.124 0 .'071 0.066 0.066 0. 061 0.055 0.047 0.046 0.106 EXISTING CONDITION ,OFF-SITE Frequency Analysis--~---- Rank Return Prqj) Period 1 100.00 0.990 2 25.00. 0. 960 3 10.00 0.900 4 5.oo. 0.800 5 3.00 .0.667 6 2.00 0.500 7 1.30 0.231 8 1.10 0. 091 -:-.r '50.00 0.980 ® I I I I I I I I I I ·I I I I I I I I I .. Flow Frequency Analysis .Time. Series File:a:predev.tsf Project Location·:sea-Tac.. . ---Annual Peak Flow Rates--- Flow Rate Rank· Time of Peak (CFS) 0.203 3 2/09/0i 15:00 0.112 ·7 1/05/02 16:00 0.207 2 2/27/03 7:00 0.073 8 8/26/.04 2:00 0.120 6 1/05/05 8:00 0.199 4 1/18/06 16:00 0.188· 5 . 11/24/06 4:00 0.3_81· 1 1/09/08 6:00 Computed Peaks ~ ., EXISTrNG CONDITION OH-SITE+ OFF-SITE ;;· . ', -----Flow Freque.ncy Analysis------- --Peaks Rank· Return Prob (CFS) Period 0.381 1 100.00 0.990 0.207 2 25.00 0.960 0.203 3 10.00 0. 900. 0.199 4 5.00 0.800 0.188 5 · 3. 00 o. 667 0.120 6 2.00 0.500 0.112 7 1.30 0.231 0.073 8 . 1.10 0.091 0.323 50.00'. 0. 980 .. © I I I I I I I I I I I I I I I 1. I I I ) 08/21/00 ' . DEVELOPED ·coNDITION HYDROLOGY For: Larson Parke It is froposed to develop the 2.06 acre site into 14 single fuinily lots with an extension of 114 Avenue Southeast and construction of SE 183rd Court and a cul-de-sac. The impervious area of the lots was considered to be th,e buildable area plus the driveway but no more than 4,000sf per lot. The proposed roadways, 0.5 acre oflsite area and wetpond were also .considered in determining the area to be used in the pond sizing. The areas are shown in the attached developed condition tabulation. The-new impervious area is 1.36 * . acres; f." • The remaining 0.70 acres qfthe site will be covered with lawns. The site will be sloped to the detention/wetpond located in the southwest comer of the site. Storm-water runoff will be collected by the roof and footing drains and the road gutters and directed to the detention pond through the piped storm-drainage system. The wetpond located below the detention pond will remove heavy sediments and pollutants for stormwater quality control. The pond 1s designed for Level 3 flow control using · KCRTS. · Level 3 is used due tci"downstream capacity concerns. The proposed detention pond will have an extra volume of 15.0% of the required volume for safety factor. The · wetpond is designed to provide the required water quality. The ground water table is high enough during wet montlis of the year !o maintain the required wetpond.water level. The pond will discharge to a new 12" 0 storm drain pipe, constructed along the north side of Lot 3 Ruth Addition in a drainage easement. The storm drain will extend to the · existing drainage system in 112th Avenue Southwest, which flows to the.Ruddells po·nd.' The emergency overflow will also discharge t~ Lot 3 and any overflow would flow to the , existing drainage system on 112th Avenue Southwe~t along the naturaUJow-path. : The wetpond length to width ratio of 3: 1 · is provided by raising the interior wall to the. wetpond water surface level ex~ept for al 'x 3, notch at the south end. The.notch at the south end will force the design water quality flow to flow all the way around the pond thereby providing the 3: 1 flow path length. I 20'wide/40' long=_3:1 OK . : .. Job# 99334 Developed Condition Hydrology tS PlllJC ORNMNZ .EASDIENT TO BE R<C<lAll<l) ..... TO FltW. f'UN APPROVAL ' " · .• • • • I .J., .t! ~ ... 1". tr; •s,~ ", . \ -1\_~ ................ T \~~TF,:Q - ~\ I L-1-- ! \ I "' l; I . N • t • \ \ • m I I 20 \ .. 'c ' I \ 112 I \ \ \ ! I ! ' . ' . ' • ~ • l % a 1 i , I ) !· .. SIDEY... \ I ' -~ N 89"41~ E. ,-,----i11--t---/7 l / I I J / ' I \ * I / // L_\ ___ \ ___ i_J \ I \ I 1,,,, I I ,'-' \I • ' ~ r--1--+- I \ ' I I I 8 I V I\ \ I ~ I I A W-+__11. 1.!_ _ _.l __ 1 __ -1J \ -~ _, . \ \ I I l ~ ~ ':: t I \ I \ \\ I ~~ EX SSMi RIM =470..01 [( 4'35.S4 8' s. 19 20 0 0 ,~\~ ,~t . ' h• '" 8 \\ ;\ I ' ---------------- .. ~ " ,;. ,;. / \ \ / ~ r ----\ \\ -_.,,-\ \j\ --\ 0'!7'"77~1 V, 18 17 -----------·-··----- lil, \ \ i ' I\, 'b ' ' \! l\: !', '"· • ., m \ l • \ I I I I " -\ --\ ---\--' '\ /'\,.,..FR<»ITY"l'D........., · \ I '<' ,S£1BACK c.-i \ f ' 1 I \ ' ' \ j \._ I __ -1----, -\-----\---\1 i . \/ ~\ 2\ ~· -· \ \ :--.._ I --~ '"'(~-JI, \ --:--\--=::-f I '\ -, \ 3 \ l ~ '..:: \ I \ \, \,_ e \ I ' ,..,i. ~ \ ', "', \ I ·-.__: l'ii"ac \ '-'-1 f-, :'-.~TIJ11)1~ T\ 4 \ '-.\ '-....j lw '---I '-. \ '-'~ \ '( I I 'I ' \'-. I ' l I \ ' ,, )/ · 'l (5 \ \ \ \ 1 ,:~, I~) , \ m\ \ I/ I l, I "'1 ~ \ ! ,--+~--~~-\_-4---~ ...:..~~-.. -~-_J • \ \ \ 30" ~ss, £GRESS I, Uffl..JTY EASOID(T PER Pl.AT OF Bll...L RUTH QlllTIOI M 'R£CDRIIED lN VIJ..(.111£ klZ• p~ 23 \ TO BE AMHJDO)~-, -=,-----\\ ___ "I - I m\ " -~'-·. ___ L F77777.l.;?'h·ld)J)Jjj~ ~717'•'),; ~-=-"1 10 9 11 \ 12 Det/fJ.OPeb ClNDt710~ l)2MtJAG-e MA-P 11 f ,$CAU': I :4o © I I I 1: I I I I I I I I I I I I I I I 06/22/2000 DEVELOPED CONDITION · ROADWAY TRACT'S' LOT1 · LOT2 LOT3. LOT4 LOT5 LOT6, · LOT7 EX HOUSE LOTS LOT9 LOT10 LOT11 LOT12 LOT13 LOT14 WETPOND TOTAL IMPERVIOUS TILL GRASS= . IMPERVIOUS AREA (SF) (ACRES) 15640 0.36 2928 0.07 2509 0.06 1883. 0.04 . 2268 0.05 3531 0.08 3607 0.08 3638 0.08 4318 0.10 2031 0.05 1735 0.04 1772 0.04 2471 2820 1939 · 1941 4356 59387 0.70 ACRES 0.06 0.06 0.04 0.04 0.10 1.36 NOTE: ON-LOT IMPERVIOUS AREA IS EQUAL TO BUILDABLE AREA+ 400SF DRIVEWAY J#99334 DEVELOPED CONDITION @ I I I I I I I ··~J{ I I I I I I I I I I I I Flow Frequency Analysis Time Series File:a:dev-ori .. tsf Project Location: Sea-Tac . ---Annual Peak Flow Rates--- Flow Rate Rank Time of Peak (CFS) 0.392 6 2/09/01 2:00 0.322 8 1/05/02 16:00 Q.411 3 2/27/03 7:00 o,. 352 7 8/26/04 2:00 0. 423 4 10/28/04 16: 00 ·:- 0.417 5 1/18/06 16:00 0.512 2 10/26/06 0:00 0. 790 1 1/09/08 6:00 Computed Peaks DEVELOPED CONDITION · ON-SITE ----~Flow FrequenGy Analysis------.- C • --Peaks --Rank Return Prob (CFS) Period· 0.790 1 100.00 0.512 2 25.00 0.471 3 10.00 0.423 4 5:00 0.417 5 3.00 0.392 6 2.00 0.352 7 1.30 o.322 ·a 1.10 0;697 50.00 0. 990. 0.960 0.900 0.800 0.667- 0 ._500 0.231 0:091 0.980 I I I I I I I I I I I I •• I I I •• I I Flow Frequency Analysis Time Series File:a:dev.tsf Project Location:Sea-Tac -7-Annual Peak FloW Rates--- Flow Rate Rank Time of Peak (CFS) 0. 453 6 2/09/01 2:00 0.369. 8 .1/05/02 16:00 0.542 3 2/27/03 7:00 0.398 7 8/26/04 2:00 · 0. 4 78 5 10/28/04 16:00 0:483 4 1/18/06 16:00 0.578 2 10/26/06 0:00 0.914 .1 1/09/08 6:00 · Computed Peaks DEVELOPED CONDITION ON-SITE+ OFF-SITE -----Flow Frequency Analysis------- --Peaks Rank Return ··Prob (CFS) Period 0.914 · 1 100.00 0.578 2 25.00 0.542 3 10.00 0.483 4. · 5.00 0.478 5 3.00 0.453 6 2.00 0.398 7 1.30 0.369 8 1.10 0.802 50.00 0.990 0. 960 0.900 0.800 0.667 -0.500 0.231 0.091 0.980 • @ I I I I I I I I I I I 1. I I I I I I I \A:>U(l.,/1; Pfl.OVI /)El) : -Retention/De~ention Fac~lity . . h . . . ·Type of Facility: Side Slope: Pond Bottom Length: Pond Bottom Width: Pond Bottom Area: Top.Area at 1 ft. FB: Ef-fecti ve Storage Depth: Stage·O Elevation: Storage Volume: Riser Head: Riser Diameter: Number of orifices: Orifice # Height (ft) 1 0.00 2 4.40 3 5.60 Detention Pond 2.00 H:lV 67.94 ft 33.97 ft 2308. sq. ft 5945. sq. ft 0 .136 ac.res 6.00 ft Vr = .""f:' (Ar + Ae, + VA,lte.) ::. ; C ~2~ + 3, ?.61 + V ..... ~-~-1-><-~-3&-;-· ) . ::: 2~60 I CM, Fr. ) 22.,337 Cl.I, Fr; • . . Oil 0.00 22337 .· 0.513 6.00 ft ft ~1----voi..t.o,..s-126. -Q1 .. 11 e.£" .· cu. .. ,... ac-ft ft' 12.00 inches 3 . Full Head Diameter ·oischarge (in) ,, (CFS) 1.10 1Ye, 0.000 _2.09 2Ye." 0.150 2. 97 :;,". 0 .151 Pipe Diameter (in) 6.0 6.0 ,\= 3, ~€,1 ~F Top Notch.Weir: None E>(T/2A VOW Mf; :. 2r; 6'/ I -221 '., 3 7 -·. ~. ~~4-Ct.t. F, ::. I~'% i,f VD!. • U&titi!cl> Outflow Rating Curve: None Stage Elevation Storage Discharge Percolation Surf Area (ft) (ft) (cu. ft) (ac-ft) (cfs) (cfs) (sq. ft) 0.00 0.00 0. 0.000 0.000 0.00 2308. 0.01 0.01 23. 0.001 0.003 0.00 2312. ·o. 02 0.02 46. 0.001. 0.005 0.00 2316. 0.03 0.03 69. 0.002 0.006 0.00 2320. 0.05 0.05 116. 0.003 0.007 0.00 2328. 0.06 0.06 139. 0.003 0.008 0.00 2332. 0:07 0.07 163. 0.004 0. 009. 0.00 2337 .. 0.08. 0.08 186. 0.004 0.009 0.00 2341. 0.09 -0.09 209. 0.005 0.010 0.00 2345. 0.21 0.21 4 94. O.Oll 0.015 0.00 2394. 0.33 0.33 784. 0.018 0.019 0.00 2444. 0.44 0.44 1055. 0.024 0.022 0.00 2490. 0.56 0.56 1357. 0.031 0.024 0.00 2541. 0.68 0. 68 1665. 0.038 0.027 0.00 2593, 0.80 0.80 1980. 0.045 0.029 0.00 2644. 0. 91 0.91 2273. 0.052 0.031 0.00 2692. 1..03 1.03 2599. 0.060 0.033 0.00 2745. L15 1.15 2932. 0.067 0.035 0.00 2798. 1.27 1.27 3271. 0 .075 0.037 0.00 2851. 1. 39 1.39 3616. 0.083 0.038 0.00 2905. 1. 50 1.50 3939. 0.090 0.040 0.00 2955. 1 .. 62 l.62 4297. 0.099 0.042 0.00 3010. 1. 74 1. 74 4661. 0.107 0.043 0.00 3066. 1.86 1. 86 5032. 0.116 0.044 0.00 3122. 1. 97 1. 97 5378. 0.123 0.046 0.00 3173. 2.09 2.09 5763. 0.132 0.047 0.00 3230. 2.21 2.21 6154. 0 .141 0.049 0.00 3287. @ ----------- I I 2.33 2.33 6552. 0.150 · 0. 050 0.00 .3345. 2.44 2.44 6922. 0.159 0.051 0.00 3398. I 2.56 ··, 2 .56 7334. 0 .. 168 0.052 . 0. 00. 3456; 2.68 2. 68 7752. 0.178 0.053 0.00 3515. 2.80 2.80 8177. 0.188 0.055 0.00 3575. 2.91 2.91 8574. 0 .197 0.056 0.00 3630. I 3.03 3.03 9013. 0.207 0.057 0.00 3690. 3.15 3.15 9459. 0.217 0.058 0.00 3751. 3 .27 3.27 9913. 0.228 0.059 0.00 3812. 3.39 3.39 10374. 0.238 0.060 0.00 3874. I 3.50 3.50 10803. 0.248 0.061 0.00 3931. 3. 62 3.62 11279. 0.259 0.062 0,. 00 3993. 3.74 3.74 11762. 0.270 0.063 0.00 4056. I 3.86 3.86 12252. 0.281 0.064 0.00 4120. 3. 97 3.97 12709. 0.292 0.065 0.00 4178. 4.09 4.09 13214. 0.303 0.066 cf. 00 4243. 4.21 4.21 13727. 0.315 0.067 0.00 4308. I 4 :33 4. 33 . 14248. 0.327 0.068 0.00 4373. 4.40 4.40 14555. 0.334 0.069 0.00 4411. 4.42 4.42 14 64 4. 0.336 0.070 0.00 4422. I 4.44 4.44 14732. 0.338 0.073 0.00 4433. 4.47 4.47 14865. 0.341 0.079 0.00 4450. 4. 4·9 4.49 14955. 0.343 0.087 0.00 4461. 4.51 4.51 15044. 0.345 0.097 0.00 4472. I 4.53 4.53 15133. 0.347 0.109 0.00 4483. 4.55 4.55 15223. 0.349 0.116 0.00 4494. 4.57 4.57 15313. 0.352 0.119 0.00 4505. I 4.69 4. 69 '15858. 0.364 0.135 0.00 4572. 4.81 4.81 16410. 0.377 0.148 0.00 4639. 4: 93 4.93 16971. 0.390 0.159 0.00 4707. 5.04 5.04 17 4 92. 0. 402 0.169 0.00 4769. I 5.16 5.16 18069. 0.415 0.178 0.00 4837 .. 5.28 5.28 18653. 0.428 0.186 0.00 4906. \ 5.40 5. 40 19246. 0.442 0.194 0.00 4 97 6. 5.52 5.52 19847. 0. 456 0.202 0.00 504 6 .. ·I 5.60 5.60 20253. 0:465 0.207' 0.00 5093. 5.63 5.63 20406. 0. 468 0.211 0.00 5110. 5.66 5.66 20560. 0.472 0.220 0.00 5120: I 5.69 5.69 20714 .. 0.476 0.233 0.00 5145. 5. 72 5. 72 20868. 0. 479 0.250 0.00 5163. 5.75 5. 75 21023 :' 0. 483 0.271' 0.00 5181. 5.79 5. 79 21231. 0 .-4 87 0.296 o.oo 5205. I 5.82 5.82 21388. 0.491 0.322 0.00 5222. 5.85 5. 85 21545: 0.495 0.340 0.00 5240: 5. 96 5. 96 22125. O·. 508 0. 372 0.00 5306. •• 6.00 6.00 22337. 0. 513 0.381 0.00 5330 . 6.10 · 6 .10 22873. 0. 525 0.712 0.00 5390. 6.20 6.20 23415. 0.538 1.300 0.00 5450. 6.30 6.30 23963. 0.550 2.050 0.00 5511. ·I 6-. 40 6. 40 24518. 0.563 2.860 0.00 5572, 6.50 6.50 . 25078. 0. 576 3.160 0.00 _. 5634. 6. 60 6.60 25944. o.~89 3. 430 0.00 5695. I 6.70 6.70 26217. 0.602 3. 680 0.00 5757 .. 6.80 6.80 26796. 0.615 3.910 0.00 5820. 6.90 6.90 . 27381. 0: 629 4 .130 0.00 5882. 7.00 7.00 27972. 0.642 4.340 0.00 5945. I 7.10 7.10 28570. 0.656 4.540 0.00 6009. I ® I I I I I I I I I I I I I I I I I I I 7.20 7.20 29174. 0. 670. 4.730 0.00 6072. 7. 30'. 7.30 29784. 0.684 .. 4. 910 0.00 6136. 7.40 i: 46 30401. · 0.698 5. 0 90 · 0. 00 · .·6201. 7.50 7.50 31025. 0. 712 5.260 0.00 7.60 7.60 31654. 0. 727 5.420 0.00 · 7. 70 7.70 32291. 0.741 5.580 0.00 7.80 7:8o 32933. 0.756 5.740 0.00 7;90 7.90 33583. 0.771 5.890 0.00 8.00 8.00 34239. 0. 786 6.040 0.00 Hyd Inflow o·utflow Peak Storage Target "G:i'!l C Stage Elev (Cu-Ft) · (Ac"Ft) 1 0.91 0.38 0.38 6.00 6.00 22337. 0.513 2 0. 45 ******* 0.20 5.56 5.56. 20072. 0. 461 3 0.58 ******* 0.18 5.16 5.16 18093. 0. 415 4 0.48 ******* 0.15 4; 87 4.87 16707. 0.384 5 0.54 ******* 0.15 4.80 4.80 16381. 6.376 6 0.48 ******* 0.06 3.8.9 3. 89 · 12362. 0.284 .7 0.37 ******* 0.06 2. 91 2.91 8563. 0.197 8 0. 40 ******* 0.05 2.30. 2.30 6441. 0.148 -------------------~-------------- Route Time Series through Facility Inflow· Time S8ries File:a:dev.tsf Outflow Time Series File:a:rdout Inflow/Outflow Analysis . Peak Inflow Discharge: 0. 914 CFS at 6:00 on Jan 9 in Year 8 Peak Outflow Discharge: 0.381 CFS at 10:00 on Jan'· 9 in Year 8 Peak Reservoir Stage: 6.00 Peak Reservoir Elev: 6.00 .Pe?k ReservOir Storage: 22337. 0.513 Flow Frequency Analysis Time .Series File:a:rdout.tsf · .. P_roj ect Location: Sea-Tac Ft Ft Cu-Ft Ac-Ft -:---Arinual Peak Flow Rate Rank Flow Rates--- Time of Peak -----Flow Frequency:Analysis-------· ....: -Peaks · -, .:. ·, Rank ! Return Prob (CFS) 0.2·05 2 0.056 7 0 .i47 5 o.,o5o 8 0. ff64 6 0.154 4 0.178 3 0.381 1 Computed Peaks Flo'w Duration Cutoff Count CFS 0.003 0.009 0.014 41990 3541 3720 2/09/01 20:00 12/28/01 18:00 2/28/03 7.: 00 8/26/04 6:00 1/05/05 16:00 1/18/06 22:00 11/24 /06 7:00 1/09/08 10:00 (CFS) (ft):',. Period 0.381 6.00 1 100.00. 0.205 5.·56--1 • 2 25.00 0.178 5.16:1 3 10.00 o .154 4. 87-, · 4 5. oo· 0.147 4.80---·· 5 3.00 0 .064 0.056 0.050 0.322 3.89· 2. 91' 2.30· 5.82 6 2.00 7 1.30' 8 1.10 50.00 from Time Series File:a:rdout.tsf Frequency CDF Exceedence_Probability %. % % 68.477 5.775 6.067 68.477 74.251 80.318 31. 523 25.749 19.682 0.315E+OO 0.257E+OO 0.197E+OO 0.990 0:960 0.900 0.800 0.667 0.500 · 0 .231 0.091 0.980 6265. 6330. 6395. 6461. 6527. 6593. "· ® I I I I I I I I I I I •• 'I I I I I I I 0.020 2977. 4.855 85.173 14.827 0.148E+00 0.026 2870. 4.680 · 89.853 10.147 o :.101E+09 0.032 1946 3.174 93.027 6. 973 0.697E-Ol o: 037. 1356 2.211 95.238 4. 762 0.476E-01 · 0.043 1066 1 .. 738 96. 977 3.023 0.302E-01 0.049 619 1.009 97.986 2.014 0. 201E--01 0.055 480 0.783" 98.769 1.231 0.123E-01 0.060 338. 0.551 99.320 0.680 0.680E-02 0.066 · 237 0.386 99.706 0.294 0.294E-02 0.072 75 0.122 99'. 82 9 0.171 .0.171E-02 0.078 8 0;013 99.842 0.158 0.158E-02 0.083 7 0.011 99.853 0.147 0 .147E-02 0.089 7 0.011 99. 865 0.135 0 .135E-02 0. 095 3 0.005 99.870 0.130 0.130E-02 0.100·· 1 0.002 .99.871 0.129 0.129E-02 0.106 1 0.002 99";973 0.127 0.127E-02 0,112 7 0.011 99.884 0.116 0 .116E-02 0.118 5 0.008 99.892 0.108 0.108E-02 0.123 6 0.010 99.902 0.098 0.978E-03 0.129 8 0.013 99.915 0.085 0.848E-03 0.135 7 0.011 99.927 0.073 0.734E-03 0.141 5 0.008 99.935 ·0.065 0.652E-03 0 .14 6 6 0.010 .99.945 0.055 0.554E-03 0.152 5 0.008 99.953 0.047 0.473E-03 · 0.158 4 0.007 99.959 0.041 0.408E-03 0.164 3 0.005 99. 964 0.036 0. 359E_-03 0 .169 3 0.005 99. 969 0.031 0.310E-03 0.175 4 0.007 99.976 0.024 0.245E-03 0.181 4 0.007 99.982 0.018-0.179E-03 0.187 2 0.003 99.985 0.015 0 .14 7E-03 0.192 1 0.002 99.987 0.013 0.130E-03 0.198 4 0.007 99.993 0.007 0.652E-04 0. 20"4 2 0.003 99.997 0.003 0.326E-04 Duration Comparison•-Anayls.i~ Base File: a:predev.tsf New File: a: rdout. tsf Cutoff Units: Discharge. in CFS -----Fraction. of Time----.----------Check of Tolerance------, Cutoff Base New %"Change Probability 0.061 I 0.67E-02 0.64E-02 -4.6 I 0. 67E-02 0.072 I 0.49E-02 0.17E-02 -65.6 I 0.49E-02 0.084 I 0.37£-02 0.15E-02 -60.3 I 0.37E-02 0.095 I 0.26E-02 o·.-lJE-02 -50.6 I 0.26E-02 0.106 I 0.17E-02 0.13E-02 -26.4 I 0.17E-02 .o, 118 ·1 0.13E-02 O.liE-02 -18.5 I .0.13E-02 0.129 I O.lOE-02 0.85E-03 -16.1 I O.lOE-02 o·; 140 I 0.75E-03 0 .-67E-03 -10.9 I 0.75E-03 0.152 I 0.60E-03 0.49E-03 -18.9 I 0.60E-03 0.163 I 0.38E-03 0.36E-03 -4.3 I 0.38E-03 0.174 I 0.24E-03 0.26E-03 6.7 I 0.24E-03 0.186 I 0.13E-03 0.15E-03 12.5 I 0.13E-03 ' 0.197 I 0.98E-04 0.82E-04 -16.7 I 0.98E-04 Maximum positive excursion -0.009 cfs ( 5.0%) occuring at 0.183 cfs on the Base Data:a:predev.tsf and at 0.192·cfs on the New Data:a:rdout.tsf Base New %Change 0.061 0.060 -o·. 7 0. 072 ' 0.062 -13:6 0.084 0.064 ·-23-: 2 0.095· 0,067 .-~29.5 · 0.106 0:071 .;33·. 2 0 .118 0. 094 -19.9 0.129 0:121 -6;0 . 0.140 0.134 -4.3 0.152 0.144 -4 ·. 9 0.163 0.162 -0.7 0.174 0.175 0.6 0.186 0.192 3.6 0.197 0.196 -o·.5 r ' ! ! ® I I I I I I I I I I I I I .1 I I I I I Maximum negative excursion -0.036 cfs (-34.0%) occu.rj_.ng. at 0_.106 cfs·'on t_ht\J~ase Dat~:-<?,:~redev.tsf · and at 0.070 cfs on the New Data:a:rdout.tsf . f'1 R.<:T c.u To FF =: -0 • 1 t. c O , ' • C)t=,. eEHA-!IJlt--lG CUTOFF .( 10% • Oil HDiE TttAN 1/2 OF me CUTO~ l-/.4Vt; NEeATIVE" it:'"Rc£NTA(rE ~AtJ~ MA-X' Po~1r1ve: ex-cu.12e;,01v -= ~% < to~. . ', oi.. · -~- • ' • Dt. I Discharge (CFS) I oin f oo ----~l~~----o--+-_rs ____ .---+o.o_g _· __ 0.,....12 ___ 0-+)_5 ____ o.+-~s ___ o.~1 . I I I 1 I I I I o . .I,. ~ 0 ' w m f i f 0 ., I I I I I I I 0 _J 0 I I I .. @ • <:, I I I I I I I I I I I I I I .. I I I I I K I N G CO U NT Y, WA S H I N G T O N, S U R FA C E WA T E R D E S I G N M A N U A L FIGURE 4.4.7J RISER INFLOW CURVES 'ti' C: 0 . ~ ~ tll. ~ m ~ u ~ :s :, 1, 2 0 100 10 Weir Flow Orifice Flow ----- ]! ' ' , ' r - - r r r r ' ' : ,, .. ; .. ,. . . . . . . , ... " ' -- . " . ; i l' ' ! !!" -I· i. , , : ! I I ·; r I ' 1, ·, ,, ,, .,, , r 1 r 0.1. \ I r r f 1.0 ' . HEAD IN FEET (measured from crest of riser) SOURCE: USOA-SCS ', QWIER = 9.739 DH312 'QORIFICE = 3.782 D2H1l2 a in els. D and H in feet £M£2t!:>&f'Je...w oUl:fFLL,W SPILLWA'-1 !311<.0 CAC,,,1= DE.S11,,IJ 4.4.7-10 . "·· 36 3,3 30 27. · ci, 24 Q) .c u 21 ~ ~ Q) 18 .; E "' a 15 ~ Q) "' -ii: ' 12 - 10 ~ ·, J . i .. 10.0 . ' i . '.. T ;~ 450, Ge> ' 456. 50 ,, . ' ' 1/90. (@ I I I I I I I I •• I I :I .• . •• I I I I I I DATE: 06/23/2000 JOB NUMBER: 99334 VERTICAL GRATE DESIGN I I I I I I I - L=? '· 0 · C ,,2 Q 100 = (L -0.2 H) H I I -,. 0.914 = 3.31[L -0.2(0.5)] 0.5'(3/2) L = 0.88 ft :SAY . 1.00ft .... >--- H = 0.50 ft P = 6.00 ft WHERE: . O,oo = 0.91 cfs L = LENGTH OF GRATE H = 0.50 -ft C = 3.27 + 0.4 H/P ·, -3.30. ft· ® 'i ! I I I I I I I I I -I I -I ;I I I I I I I DATE: 06/23/00 JOB: 99334 · WATER QUALITY DESIGN -BASIC WETPOND STEP 1: VOLUME FACTOR (f) = 3 STEP 2: RAINFALL FROM MEAN ANNUAL STORM (R) =. 0-47 inch STEP 3: VOLUME OR RUNOFF FROM. MEAN ANNUAL STORM (Vr) Vr = (0,9 Ai+ 0.25 Atg + 0.10 Alf+ 0,01 Ao) x (R/12) ' , WHERE: Ai = AREA OF IMPERVIOUS SURFACE Atg = AREA OF TILL .SOIL (GRASS) Alf= AREA OF TILL SOIL (FOREsn Ao,= AREA OF OUTWASH SOIL (GRASS OR FOREST)· • Vr = [0,9 (59387) + 0,25 (30492) + 0, 10 (0) + 0,01 (0)) X (0-47/12) = 2392 cu. ft STEP4: WETPOND VOLUME Vb= f (Vr) = 7176 cu.ft. = 59387 sf = 30492 sf = O sf = 0 sf Ar:. 1,727 + 1,64(": 3,3SI t;F " EL~ 444.00 ~--. ---\------~------7 h~ eL ~ 4-44.00 . h ~{, 1 A_e.-_-4_6~+2.~ :.124-~F ~ EL :c. 4-40.00 EL"' 43S. 00 .....L-----~----' .4e; :. 11 I (.F VOL.UH£; i'/£.0 V1D°t::b v, ::. .!L ( A-r + Ae, + Y-1.; Ae, ) 3 =-1('3,3BI +724+V::.;?81;"';24) + ~(465"+ 111 -t V46~xlll ) = i,S"~tt + S"?>S" -:. 8, 0'14 Cl.ol, Fr. > 71 176 CU. l"T', .'. Ot. volu oW\ ~ ciu. I = 2.825 <:F C @ I· I I I I I I I I I I I I I I I I I I SECTIONV · ·CONVEYANCE SYSTEM .· ·ANALYSIS -AND DESIGN . " I DMP, INC. JOB "1Cl2x, Engineering · Surveying -Land Planning SHEET NO_ OF 1215 So. Central Ave. Suite 133 CALCULATED BY DATE 01/12. loo I KENT, WAS.HINGTON 98032 I (253) 854-9344 CHECKED BY DATE FAX (253) 854-6663 SCALE 1. I .1 .. . ' : : : : : ' . '.:: ! ., . . ",.,.J : ' . • ! : ! !,.,~ r=-• !<"'.1 ,;: A ( .... , ,.,,._., ' ... : : '"""'"','··, I __ ,._, .......... : ............ , ........... , ..... •······ .... : -u, "A-" '"' ,-,::.1:: Ju~ r,i:1 U i= T ,,, I DA-"JF 11-1 ' i ;:;/. i tf1\ :~ ~ r11..r; : .. ' : . ... ; .•.......•. i. ••.. . ' ... "' L"7)1 n. \ F) ,7,L, ' : ' : : ! ' ' ' I E 'A, ' ' r, -,,; 4 /. /. i;e /J ~ 'CJ I 1 n 1 Toi J,; .::: /,,.' 'r..:. A, ! ~I ' "-· '.A "' I ~ I -. . ' . '. i' ,., ~I'. --., l.)J 1, , • " F/Y\C.71 • . : l::J~:A : ' ·-'n: 1.~0. DIA ,,,,., c -(\ ., / " ll I' -? ' '.4 A-, I • ) I I Ar :, . :c _, f, l lL -\ . ,,!. -t\ ., 'h',, ' ' ' : :. • ; ' : . . : ' ' : I ' . : ' ' : : : , I ; : : .; ' .... ., , ... , .. , ' .. •· .\ ........... :1 : ..... , .. . : . : : ' : . : ' ' .... J . ; .. ...... -i .......... , ....... ······· . : . ; -! ! ·1 ., ······· , ........ .. .. .. ' , ...... ' ' ' : : ', ' : ,. •... ······ , ••.......... .... , .... : .. , .. ,., I ! ' . 'i i ' ' ', I ' . ' . . i ' ' ! ' : ' : • ' : : • . .-.. I ' . ! : ' i : . ·, ! ' ' i ' : : ' ' . I , .. ! l ' ' / ;'\ ' . : . .. 1..·, ' : : .... ' ......... I ' ! : : ' ' - 79.5 LF -12' CHP @ 1.01% CB R!M=428.4 :ti~§~ u~: g~~ s.> l 1.12:t. SDHH R!H=429,9 --~I :I' .. , SE !E=426.0 (12' CHP N,E,1,/) 1o3FtlJ-DI el CB R!H=428,3 1[=424.9 02• CHP N.> IE=424.9 <12· CMP,;;,.--,..,;:,:,., ---- 77 I .~/ -:.::·~-- .Ei<. 1>erErJnoN jbNI) t-AA-X. w.~. E. EL .42.s;-.oo ~"...., C i ' I I I ' ·, V 'b "'1'< '·..._ 5itJf\ 'i / ·'t· r, /' f \ I y; i;.~,;,:LL,-2 ) /' 0,34 CSNo. 9-TtPEI, W/ S0UD LOCKING UD Rll-429.62 2 11.II 'i I '·, LE.•424.72 NOTE: 1. STRUCTURES le OlltER ElCISTING FEATURES OIS1IJRllfl) DURING CONSlRUCTION SHALL BE RESTORED OR REPLACED TO OAIGINAL CQIJITION. M ' 0' ·;/:;, 'O' 2. PR()lll1lE CON1NJOUS 1'CX£S5 TO ALL LOlS MfEClED BY <Xll§IRIJC'IIOII._ LO_TS_ 1, 2._J. 1 ·RIA ') o· fW ,,~ ,... 1" 4~·,WALL ,.,, o\'EHfl.DW S1RUC11JllE-1"1'PE I W/CONE GRAlE DEBIIIS (SEE DETAIL SHT. 9) Rll-450.50 LE.=443.95 ?~7, 4.41.f 1:Z-CPEPO 1.1@; 3 '· i --_T ! ~: !' ·, 442-ll .... 2. 443 I \ -i--- h ~ ~ 0' a., \ ,, I <;CAL£ I :. !)0 (jj J I I I I I_ I I I I I I I I I I I I I I Flow Frequency Analysis . ·.Time Set'ies File: a: osleft15. tsf,..,· . ": PI'oje'Ct Location: sea-Tac ---Annual Peak Flow Rates--- Flow Rate Rank Time of Peak {CFS) 0.125 6 2/09/01 12:30 0.091 8 1/05/02 15:00 0.303 -2 12/08/02 17:15 0.092 7 8/23/04 14 :30 0.136 5 10/28/04 16:00 0.142 4 10/27 /05 10:45 0.158 3 10/25/06 22: 45 0.428 1 1/09/08 6:30 Computed Peaks TiH E -;e12.rc~ OFF-~1T€ 'JX)W~~ (t~ k!N. T1H8 '7T£~) Osleftl5 -----Flow Frequency Analysis------- --Peaks Rank Return Prob (CFS) Period 0.428 1 100.00 0.303 2 25.00 0.158 3 10.00 0.142 4 5.00 0.136 5 3.00 0.125 6 2.00 0.092 7 1.30 0.091 8 1.10 0.387 . 50.00 0.990 0. 960 0.900 0.800 0. 667 0.500 0.231 0.091 0.980 I I I I I I I I I I I I I I I I I I I Flow Frequency Analysis Time Series File:a:convey15.tsf' Project Location:Sea-Tac ---Annual Peak Flow Rates--- Flow Rat~ · Rank Time of Peak (CFS) 0.733 6 8/27/01 18:00 0.520 8 1/05/02 15:00 1. 58 2 12/08/02 17:15 0.590 7 8/23/04 14:30 0.853 5 11/17/04 5:00 0.873 4 10/27/05 10: 45 1.02 3 10/25/06 22:45 2 .·24 1 1/09/08 6:30 Computed Peaks ~HHATtDN of T11-1e ~~/2/e;r;,. ()tJ. s,re -t OFF· ,;,re; LiP<;fi:£Ai'-1 ( , r 1--11 tJ . T11-1 e .,,e-;,r ) Conveyl5 -----Flow Frequency Analysis------- -~ Peaks Rank Return Prob (CFS) Period 2.24 1 100.00 1.58 2 25.00 1.02 3 10.00 0.873 4 5.00 0.853 ·5 3.00 o. 733 6 2.00 0.590 7 1.30 0.520 8 1.10 2.02 50.00 0.990 0. 960 0.900 0.800 0.667 0.500 0.231 0.091 0.980 ------------------- . Project LARSON PARK Proj No: 99330 Date: 01/12/01 Pipe Pipe Segment Q Lngth CB to CB (cfs) (ft) PD1 to 11 2.24 48.2 11 to 5 2.24 39.1 5 to 4 2.24 139.7 4 to 3 2.24 25.8 3 to 2 2.24 77.2 2 to 1 2.24 24.4 5 to 6 2.24 22.4 11 to 12 2.24 64.4 "' . P02 10 EX 2.67 71.8 EX to 9 2.24 130.5 9 to 8 2.24 40.6 8 to 7 2.24 239.5 7 to OMH 2.24 53.6 Pipe "n" Outlet Inlet Pipe Size Value Elev Elev Area (In) ; (sf) 12 0.012 442.00 446.50 . 0.79 12 0.012 446.50 451.65 0.79 12 0.012 451.65 466.24 0.79 12 0.012 466.24 466.37 0.79 12 0.012 466.37 466.76 0.79 12 0.012 466.76 467.00 0.79 12 0.012 451.65 451.87 0.79 12 0.012 446.50 447.00 0.79 12 0.012 421.85 423.41 0.79 12 0.012 423.41 424.72 0.79 12 0.012 424.72 427.60 0.79 12 0.012 427.60 441.68 0.79 12 0.012 441.68 443.95 0.79 OMH to cs 2.24 4.4 12 0.012 443.95 444.00 0.79 cs to PD1 2.24 ,,. I (S> 24.2 12 0.012 444.00 442.00 0.79 PD1: LARSON PARK DETENTION POND PD2: RUDDELLS DETENTION POND EX: EXISTING CATCH BASIN OMH: OVERFLOW MANHOLE CS: CONTROL STRUCTURE BACKWATER CALCULATION SHEET 100-YR DESIGN STORM Pipe Frie-Entr Entr Entr ExH Outlet Pipe Vel TW tion HOL Loss Head Head Contr Vel Head Elev Loss Elev· Coeff Loss 'LOss Elev (fps) (ft) (ft) (ft) (ft) (ft) (ft) (ft) 2.85 0.13 450.00 0.16 450.16 0.5 0.06 0.13 450.35 2.85 0.13 450.39 0.13 450.52 0.5, :0.06 0.13 450.71 2.85 0.13 452.54 0.47 453.01 0.5 0.06 0.13 453.20 2.85 0.13 467.17 0.09 467.26 0.5 0.06 0.13 467.45 2.85 0.13 467.38 0.26 467.63 0.5 0.06 0.13 467.82 2.85 0.13 467.86 0.08 467.95 0.5 0.06 0.13 468, 13 2.85 0.13 452.54 0,07 452.61 0.5 0.06 0.13 452.80 2.85 0.13 450.39 0.21 450.60 0.5 0.06 0.13 450.79 3.40 0.18 425.00 0.34 425.34 0.5 0.09 0.18 425.61 2.85 0.13 425.49 0.44 425.92 0.5 0.06 0.13 426. 11 2.85 0.13 425.99 0.14 426.12 0.5 0.06 0.13 426.31 2.85 0.13 428.47 0.80 429.27 0.5 0.06 0.13 429.46 2.85 0.13 442.56 0.18 442.74 0.5 0.06 0.13 442.92 2.85 0.13 444.82 0,01 444.84 0.5 0.06 0.13 445.03 2.85 0.13 444.90 0.08 444.98 0.5 0.06 0.13 445.17 -"' .. . . Inlet Appr Bend Bend June June Contr Vel Loss Head loss Head HW Elev Head Coefl Loss Coell Loss Elev (ft) (ft) (ft) (ft) (ft) 447.50 0.13 1.320 0.167 0.000 0.00 450.39 452.65 0.13 0.020 0.003 0.138 0.02 452.54 467.24 0.13 0.300 0.038 0.174 0.02 467. 17 467.37 0.13 0.420 0.053 0.000 0.00 467.38 467.76 0.13 1.320 0.167 0.000 0.00 467.86 468.00 0.00 0.000 0.000 0.000 0.00 468.13 452.87 0.00 0.000 0.000 0.000 0.00 452.87 . 0.00 0.00 0.000 0.000 0.000 0.00 450.79 424.57 0.13 0.023 0.004 0.000 0.00 425.49 425.72 0.13 0.007 0.001 0.000 0.00 425.99 428.60 0.13 0.009 0.001 0.000 0.00 428.47 442.68 0.13 0.021 0.003 0.000 0.00 442.56 444.95 0.13 0.000 0.000 0.000 0.00 444.82 445.00 0.13 0.000 0.000 0.000 0.00 444.90 443.00 0.00 0.000 0.000 0.000 0.00 445.17 Q,oo o~-f/TE + or,r ~.rffc (VP.frilli"Al-1) rOTT•S/?"c(~()c,JtvSTP.cAH) :: 2. 2-'I f-o. V 2~ "' 2, G. 1 cf'. Upstm Grate Check Elev HW (ft) 451.00 OK 454.87 OK 472.37 OK 471.85 OK ·410.10 .OK· 470.10 OK 454.87 OK 450.80 . OK 426.86 'OK 429.62 OK 432.47 OK 450.00 OK 450.50 OK 452.50 OK 450.00 OK 11 . I I I I I I . --· SECTION VI , I · ·· ·• SPECIAL REPORTS & STUDIES I I , . I I I I I I . •• I I I I . . I I . I •• I · SECTIONVII I I OTHER PERMITS I I I I I I I I I I I I I I I I I I I I I I I I I I I I I ', " ' SECTION VIII T .E.S.C. ANALYSIS AND DESIGN . I I I I I I I I I I I I I I I I I I I SEDIMENT POND DESIGN SURFACE AREA SA= FS (Q,/V,) where: Q2 = . Design inflow based on the peak discharge from the developed 2-yr runoff event from the contributing drainage area (See Section 4). = 0.45 els Vs = The settling wlocity of the soil particle of interest. = 0.00096 ft/sec FS = Safety factor of 2 to account for non-ideal settling. therefore SA= 2 x 0.45 /0.00096 = 943.8 s.f. sA Provkted 1500 s.f. ( Area measured using Softdesk Design Module) -> 943.8 s.f. therefore ok PRINCIPAL SPILLWAY Q,, = Developed 10-yr peak flow = 0.54 cfs D= Q=, /(9.739xHn) = 0.06 ft D = ( Q,.,=/ ( 3.782 x H'")) "= 0.38 ft therefore use D = 12 in diameter riser EMERGENCY OVERFLOW SPILLWAY. Q,00 = D8""1oped 100-yr peak flow = 0.914 cf; L= ( Q~/(( 3.218"Hn)) 0 ( 2.4 H)) = therefore use L = 6 ft DEWATERING ORIFICE where: 2.70 ft D = diameter in feet H= 2 QWEJR and Q(HflCE : Q,o where: L = length of spillway H= 0.2 Feet Ao= As(2h)o.s where : Ao= orifice a;~"°c{(s.f.) 0.6 x 3600 Tg0·' 0.010 s.f. 0 = 13.54 x ( A. )"00 1.37 in therefore use D = 1 3/8" in diameter orifice A.= pond surface area (s.f.) 1500 SF h = head of water above orifice (ft) = 2 ft g = acceleration of gravity (32.2 ft/sec') T = dewatering lime (24 hours) where : D = orifice diameter (in) ... (I) I I I I I, I ·I I I I I I I I I I I I I NARRATIVE FOR LARSON PARKE-ESC PLAN The site is sloped from northeast to southwest with soils that are resistant to erosion. The site is already somewhat developed with a house, lawns and driveway so clearing and· grading will be somewhat less than normally would occur. The silt fence will be · extended around the lower portion of the site to insure that no silt laden water leaves the site. A construction entrance will be provided; A large sedimenf'pond will lie constructed on the site of the future detention/wetpond. A "V" ditch will drain the site't9 the sediment pond. When the storm drainage pipes are installed they will be' provided with CB protection and will drain to the sediment pond. During dry weather, and 'after the site has been mostly graded and stabilized and the storm drainage system installed, the sediment pond will be enlarged into the detention/wetpolid: As thewetpond will be below the pond outlet elevation there is little chance than any silt laden water could Leave the pond during construction. The remaining ero'sion·conirol structures will be removed once the site is fully stabilized. When the storrri drainage system is flushed the silt laden water will be pumped to ·a temporary pond· or a grassed area, so that sediment will not enter the wetpond. Requirements of Section 1.2.5 are met as follows: Clearing limits are shown on the TESC Plan on Sheet I 0. The trees to be saved will be flagged. Cover Measures· are covered by notes call for hydroseeding disturbed soil and straw mulch to be applied as needed. · ·' Perimeter Protection will be provided by leaving as much of the site as possible in its natural state to minimize erosion potential and allow for natural filtration. Silt fences will be installed around the lower Yz of the siteto insure that no silt laden water leaves the site. Traffic Area Stabilization will be provided by a I 00 foot rock construction entrance. Sediment Retention will be provided by a sediment pond located in the area of the future detention/wetpond. Surface water controls will be provided by swales, and eventually the piped drainage system and Jot grading. Dust control will be provided by watering the site if necessary .. I I I I I I I- I . .· SECTION IX· . BOND QUANTITIES, FACILITY I .· ... :· .. ·SUMMARIES, AND DECLARATION OF COVENANT .. I I I I I .I I I. I I ·:,, j. -----------..... _ ------ g Site Improvement Bond Quantity Worksheet. King County Department of D&'(elopment & Environmental SeJVlces 900 Oakesdale Avenue Southwest Renton, Washington 98055-1219 Project Name: _,LA::..::.R:::S:.::0:.:.N;:.P:_:Ac,Rc,Kc:.. ______________ _ Location: SE 1/4 NE 1/4 SEC 32, T23N, R5E, WM Clearing greater than or equal to 5000 board feet of timber? -~~~~~ yes _______ .no If yes, · Forest Practice Permit Number:. _______ _ (RCW 76.09) Page 1 of9 S:PUBLICILUSDILUIS\Bond Quan Worksheet Date: 07/21/2000 SIERRA Project No.: SIERRA Activity No.: Note: All .price~ include labor, equipment, materials, overhead and profit.. Prices·are from RS·Means data adjusted for the.Seattle area or from local sources if not included in the RS Means database. ' . . ,. ,. I ., . ·.1 .. Unit prices updated: 12/97 Version: 6/4/99 Report Date: 07/12/2000 ., I I I I I I I I I I I I I I I I I I I EROSION/SEDIMENT CONTROL Backfill & compaction-embankment Check dams, 4" minus rock Crushed surfacing 1 1 /4" minus Ditching · Excavation-bulk· . :.Fence, silt Fence, Temporary (NGPE) Hydroseooing Jute Mesti · Mulch, by hand,· straw, 3" deep . Mulch, tiy machine," straw, 2" deep · Piping, temporary, CPP, 6" · Piping, temporary, CPP, 8" Piping, temporary, CPP, 12" Plastic covering; 6mm thick, sandbagged · Riprap, •machine"placed; slopes Rock Construction Entrance, 50'x15'x1' Rock Construction Entrance, 100'x15'x1' · Sediment pond riser assembly Sedimenttrap, 5: high berm · Sediment trap, 5' high, riprap spillway berm section Seeding, by tiand Sodding, 1" deep, level ground Sodding, 1" deep, sloped ground TESC Supervisor Water truck, dust control WRITE-IN-ITEMS Catch Basin Protection · Unit Price $4.89 $58.70 $74.30 $7.03 · $1.30 $1.20 $1.20 $0.51° $1.26 $1.75 $0.46 $9.30 $14.00 $18.00 $2.00 $33.98 $1,273.34 $2,546.68 $1,695.11 $15.57 $59.60 $0.44 $5.24 $6.48 $65.00 $85.00 $60.00 Unit Quantity Cost CY $0.0 Each 10 $587.0 CY $0.0 CY 240 $1,687.2 CY 658 $855.4 LF 220 $264.0 LF $0.0 SY · 4440 $2,264.4 SY $0.0 SY $0.0 SY 4172 $1,919.1 LF $0.0 LF $0.0 LF $0.0 SY $0.0 CY $0.0 Each $0.0 Each 1 $2,546.7 Each 1 $1,695.1 LF · .. • 100. $1,557.0 LF 6 $357.6 SY 1066 $469.0 SY $0.0 SY $0.0 HR $0.0 HR $0.0 Each $0.0 Each 10 $600:0 . $0.0 ESC SUBTOTAL: 114,802.6 COLUMN: A ------------·--· ·--· -··-··----- Existing Future Public Road · . Private Bond R.O.W. lmprovments & lmprov 1 Reduction Drainage Facilities . .. Unit Price Unit Quant Cost Quant . •Cost Quant Cost Quant Cost · !,!;NEBAL ITEMS Backfill & compaction-embankment $4.89 CY $0.0 $0.0 250 $1,222.5 Backfill & CompacUon-trench $7.42 CY. • 60 $445.2 200 $1,484.0 $0.0 Clear/Remove Brush, by hand $0.31 SY $0.0 $0.0 $0.0 Clearlng/Grubbing/Tree Removal $7,718.40 Acre $0.0 0.7 $5,402.9 · $0.0 Excavation-bulk . $1.30 CY $0.0 2282 $2,966.6. · · · $0.0 Excavation-Trench $3.53 CY 60 . $211.8 200 $706.0 · $0;0 Fencing, cedar, 6' high $16.13 LF $0.0 ... · .. · · ' $0,0 .· .. . $0.0 Fencing, chain link, vynll coated, 6' high $11.69 L.:F $0.0 345 $4,033:1 · •.. . $0.0 Fencing, chain link, gate, vynll coated, 20' $1,105.92 Each $0.0 1 : '$1 ;105.9 . · •,: ,$0.0 · Fencing, split rail, 3' high $10.54 LF · · $0.0 . ' . .. $0.0 ... ' ... .<. ··, $0.0 Fill & COmpact-common barrow $19.63 CY $0.0 $0.0 · $0.0 Fill & compact-gravel base $22.16 CY $0.0 $0.0 $0.0 Fill & compact-screened topsoil $32.91 CY $0.0 $0.0 $0.0 Gablon, 1 'Z' deep, stone filled mesh $47.23 SY $0.0 $0.0 $0.0 Gabion, 18" deep, stone filled mesh $65.09 SY $0.0 , $0.0 $0.0 Gabion, 36'' deep, stone filled mesh $115.20 SY $0.0 $0.0 $0.0 Grading, fine, by hand $1:76 SY $0.0 $0.0 . $0.0 Grading, ·fine, with grader $0.83 SY $0.0 $0.0 . $0.0 ' Monuments, 3' long $117.50 Each $0.0 5 $587.5 $0.0 Sensitive AreaS Sign $2.50 Each $0.0 $0.0 $0.0 Sodding, 1~ deep, sloped ground $6.49 SY $0.0 $0.0 $0.0 Surveying, line & grade $685.44 Day $0.0 3 $2,056.3 $0.0 Surveying, lot location/lines $1,353.60 Acre $0.0 $0.0 $0.0 Traffic control crew (2 flaggers) $74.07 HR $0.0 $0.0 $0.0 Trail, 4" chipped wood $6.60 SY ,. $0.0 $0.0 $0.0 Trail, 4H. cfuShed cinder $7.24 SY $0.0 $0.0 $0.0 Trail, 4" top course $7.12 SY $0.0 $0:0 .. $0.0 Wall, retaining, concrete . $38.40 SF $0.0 2220 $85,248.0 $0.0 Wall, rockery $8.25 SF $0.0 0 . $0.0 300 $2,475.0 . . . . . :· ~ ' '. -... .. 1 • SUTOTAL: $657.0. $103,590.3 . . ·: $3,697.5 '· Q) ----------··------·--·- Existing Future Public Road Private .. Bond R.O.W. lmprovments & . · . lmprov · Reduction Dralnaae Faclllties · . .. . Unit Price Unit Quant Cost Quant .Cost: .. , Quant Costr. Quant Cost ROAD IMPROVl;ME!fl ... .. . -. . AC Grinding, 4' wide machine< 1000Sy $20.00 SY $0.0 . $0.0. $0.0 AC Grinding, 4' wide machine 1000-2000Sy $5.00 SY $0.0 · $0.0 .. $0.0 AC Grinding, 4' wide machine> 2000sy $1.20 SY $0.0 $0;0 $0.0 AC Removal/Disposal/Repair $35,77 SY $0.0 . : . $0.0 · $0.0 Barricade, type I $26.11 LF $0.0 .. . ·$0:0 -.. ·$0.0 .. Barricade, type Ill (Permanent) $39.17 LF $0.0 · ·$0:0 ... -. $0.0 -- Curb & Gutter;rolled $11:54 LF $0.0 920 $10,616.8 $0.0 Curb & Gutter, vertical $8.43 LF $0.0 $0.0 $0.0 Curb & Gutter, demolition and disposal $11.81 LF $0.0 $0.0 $0.0 Curb & Gutter, extruded asphatt $2.12 LF $0.0 $0.0 $0.0 Curb & Gutter, extruded concrete ' $2.23 LF $0.0 $0.0 $0.0 Sawcut, asphalt, 3" depth $1.61 " LF $0.0 $0.0 $0.0 Sawcut, concrete, per 1" depth $1.47 LF $0.0 $0.0 $0.0 Sealant, asphalt $0:86 LF $0.0 $0.0 $0.0 Shoulder, AC, (see AC road unit price) SY $0.0 $0.0 $0.0 Shoulder, gravel, 4" thick $6.55 SY $0.0 $0.0 $0.0 Sidewalk, 4" thick $26.54 SY, 3 $79.6 $0.0 $0.0 Sidewalk, 4" thick, demolition and disposal $24.11 SY 3 . $72.3 $0.0 . $0.0 Sidewalk, 5" thick $30.38 SY $0.0 232 $7,048.2 $0.0 Sidewalk, 5" thick, demolition and disposal $30.13 SY $0.0 " $0.0 . $0.0 . Sign, handicap $74.16 Each $0.0 ·.' ·:$0:0 . . . ... :$0.0 · . Striping, per stall ' $5.06 Each $0.0 .. $0.0 .. ... -. $0.0 Striping, thermoplastic, (for crosswalk) $2.07 SF $0.0 ' .... -'., . $0.0 '. ', $0.0 Striping, 4" reflectorized line $0.22 LF $0.0 so:o $0.0 SUTOTAL: $152.0 $17,665.0 $0.0 w ---------. --·-··-·-·-:.·.----.. ; . . ' '. ·., .. Existing Future Public Road ·,. Private . Bond R.O.W. lmprovments &. . · · . lmprov Reduction · Dralnaae Facilities Unit Price Unit Quant Cost Quant Cost Quant Cost· Quant Cost. ROAD SUEACING For KCRS'93, (addltlonal 2.5" base) add: $3.13 SY $0.0 $0.0 $0.0 AC Overlay, 1.5" AC $6.43 SY $0.0 $0.0 $0.0 AC Overlay, Z' AC $7.61 SY $0.0 $0.0 $0.0 AC Road, 2"; 4"rock, First 2500 SY $14.99 SY 47 $704.5 2500 $37,475.0 $0.0 AC Road, Z', 4"rock, Qty. over 2500 SY $11.62 SY $0.0 142 $1,650.0 $0.0 AC Road, 3", 4"rock, First 2500 SY $17.12 SY. $0.0 $0.0 $0.0 AC Road, 3", 4"rock, Qty. over 2500 SY $13.75 SY $0.0 $0.0 $0.0 AC Road, 5", First 2500 SY $12.67 SY $0.0 · $0.0 $0.0 AC Road, 5", Qty. over 2500 SY $12.12 SY $0.0 $0.0 $0.0 AC Road, 6", First 2500 SY $14.57 SY $0.0 -·· · $0.0 $0.0 AC Road, 6'', Qty. over 2500 SY $14.02 SY $0.0 · $0.0 . -·-. $0.0 Asphalt Treated Base, 4" thick $8.01 SY $0.0 $0:0 . · $0.0 Gravel Road, 4" rock, First 2500SY $9.92 SY $0.0 $0.0 .. $0.0 Gravel Road, 4" rock, Qty. over 2500SY $6.55 SY $0.0 $0.0 $0.0 PCC Road, 5", no base, over 2500SY $18.70 SY, $0.0 $0.0 $0.0 PCC Road, 6"; no base, over 2500SY $19.02 SY $0.0 $0.0 $0.0 Thickened Edge · $5.99 LF $0.0 $0.0 $0.0 .. SUTOTAL: $704.5 $39,125.0 $0.0 .. ··._..:. \0} ~ ~. '~' ·\ '/-:,._·~ ------------_______ , ________ _ Existing Future Public Road · Private ,·' Bond R.O.W. lmprovments & lmprov Reduction Dralnaae Facilities Unit Price Unit Quant Cost Quant Cost. Quant ·cost· .. Quant Cost !lRAINAG~ ·-·.:' . Access Road, R/0 $14.56 SY $0.0. 134 $1,951.0 $0.0 Bollard-fixed . $209.34 Each $0.0 · $0.0 .. $0.0 Bollard-removable $393.34 Each $0.0 . $0.0 $0.0 • (CBs Include frame and lid) . --. ··.,·, ' : ' .. CB Type I $1,093.60 Each 1 $1,093.6 8 --$8,748:8 .. . · · · $0.0 CB Type IL $1,246.60 Each $0.0 · $0.0 · · $0.0 .. CB Type II, 48" diameter $1,768.32 Each $0.0 4 '$7,073.3 .. .. -, .. ·-$0.0 " for additional depth over 4' $379.58 FT $0.0 12.8 · $4,858.6 ·$0.0 CB Type II, 54" diameter $1,906.56 Each $0.0 ·1 $1,906.6 .. ---·-$0.0 .. for additional depth over 4' $423.07 FT $0.0 4 . · · $1,692.3 ... ·$0:0' CB Type II, 60" diameter . $2,044.80 Each $0.0 .. $0:0 . · ... -• $0.0 · . for additional depth over 4' $466.56 FT $0.0 $0.0 $0.0 CB Type II, 72" diameter $2,793.60 Each $0.0 $0.0 $0.0 for additlOnal depth over 4' $601.92 FT $0.0 $0.0 $0.0 Through-curb Inlet Framework (Add) $318.34 Each $0.0 $0.0 . $0.0 Cleanout, PVC, 4" $113.52 Each $0.0 $0.0 $0.0 Cleanout, PVC, 6'' $152.09 Each $0.0 $0.0 5 $760.5 Cleanout, PVC, 8" $194.95 Each $0.0 so:o $0.0 Culvert, PVC, '4" $7.51 LF $0.0 $0.0 $0,0 - Culvert, PVC, 6" $10.96 LF $0.0 $0.0 . $0.0 Culvert, PVC, 8" $11.59 LF $0.0 $0.0 $0.0 Culvert, PVC, 12" $18.93 LF $0.0 . $0.0 .... $0.0 Culvert, CMP, 8" $15.00 LF .$0.0 $0:0 . · .$0.0 Culvert, CMP, 1 Z' $23.00 LF $0.0 $0.0 $0.0 ., .. . SUTOTAL: $1,093:6 . $26,230:6 $760.5 \ ·, . . .. I' • . DRAINAGE CON!INUED -. . .. ,t: :·· . . . -. -. . -.. Culvert, Concrete, 8" $18.28 . LF $0.0 . $0.0 ·$0.0 ·. . ~ .• -.. Culvert, Concrete, 12" · $26.13 LF $0.0 c•_ ; .. · .. " $0.0 . $0.0 Culvert, Concrete, 15" $32.47 LF $0.0 '• $0.0 ... $0.0 · \s) ----------· -··----··----··-··-·.-~- Existing Future Public Road • Private :,• .. Bond R.O.W. . lmprovments & l' ,. s. lmprov -Reduction · : oralnaa·e Facilities' . · ,, ' ', •'•' Unit Price Unit Quant· -Cost. Quant ·.cost,:·--Quant. · -Cost: , Quant Cost Culvert, Concrete, 18" $38.70 LF $0.0 -$0.0 . -$0.0 Culvert, Concrete, 24" · $53.10 LF $0:0 · -· $0.0 · $0.0 Culvert, Concrete, 30" $50.59 LF $0.0 · $0.0 · ··$0.0 Culvert Concrete, 36" $119.68 LF · $0.0 $0.0 $0.0 Culvert, Concrete, 42''. $137.76 LF $0.0 $0.0 $0.0 · Culvert, Concrete, 48" $152.99 LF $0.0 $0.0 $0.0 Culvert. CPP, 6" $9.30 LF $0.0 $0.0 $0.0 Culvert, CPP, 8" $14.00 LF $0.0 $0.0 $0.0 Culvert, CPP, 1 Z' $18.00 LF 172 $3,096.0 732 $13,176.0 $0.0 Culvert, CPP, 15" $20.00 · LF $0.0 $0.0 . ,$0.0 Culvert, CPP, 18" $24.00 LF $0.0 $0.0 "$0.0 Culvert, CPP, 24" $32.00 LF $0.0 .. .. $0.0 $0.0 Culvert, CPP, 30" $42.00 LF $0.0 $0.0 $0.0 Culvert, CPP, 36"' $48.00 LF $0.0 $0.0 $0.0 Ditching $7.03 CY $0.0 $0.0 $0.0 ., Flow Dispersal Trench (1436 base+) $22.60 LF $0.0 $0.0 $0.0 French Drain (3" depth) $19.65 LF $0.0 . $0.0 · 600 $11,790.0 Geotextile, laid In trench, polypropylene $2.09. SY $0,0 .$0.0 $Q.O Infiltration pond testing · $65.00 HR $0.0 $0.0 $0.0 Mid-tank Access Riser, 48" dia, 6' deep $1,396.00 · Each $0.0 -. $0.0 $0.0 Pond Overflow Spillway $12.18 SY $0.0 . $0.0 · $0.0 Restrlctor/Oil Seperator, 1Z' $908.86 Each $0.0 . 1 $908.9 $0.0 Restrictor/Oil Seperator, 15" $952.66 Each $0.0 · ·, $0.0 $0.0 Restrlctor/Oil Seperator, 1 B" $996.66 Each $0.0 ·$0.0 $0.0 Rlprap, placed $33.98 CY ' $0.0 $0.0 $0.0 Tank End Re.ducer (36" diameter) $870.00 Each $0.0 $0.0 $0.0 Trash Rack, ·12" $184.32 Each $0.0 1 $184.3 $0.0 . Trash Rack, 15" $206.32 Each $0.0 $0.0 $0.0 Trash Rack, 18" $233.82 Each $0.0 $0.0 $0.0 Trash Rack, 21" $266.82 Each $0.0 $0.0 $0.0 SUBTOTAL: $3,096.0 · $14,269,2 $11,790.0 .. . ' . .. Q) J ; ~ -·. ----------· --···:----:~---'------- Existing R:O.W. Unit Price Unit Quant eAB!SING LQI SUBFA!,l!'!!G Z' AC, 2" top course rock & 4" borrow $13.77 SY Z' AC, 1 S top course & 2.5" base course $14.99 · SY 4" select borrow $3.96 SY 1.5" top course rock& 2.5" base course $9.92 SY l{tBITE~t:HilaMS Trees 3" dia $100.00 Each Each SUBTOTAL: ' SUBTOTAL (SUM ALL PAGES): ' 30% CONTINGENCY & MOBILIZATION: GRANDTOTAL: COLUMN: ::? ~ Future Public Road Private · lmprovments & lmprov Drainaae Facilities Cost . Quant Cost Quant $0.0 $0_0 $0.0 · $0_0 '$0_0 -$0,0 $0.0 $0.0 ' . $0.0 $0.0 16 $0.0 $0.0 · $0:0 ... $5,703.1 , $1,710.9 $7,414.0 B t· .•. ' .. $0.0 ' $200;880_0 $60,264.0 $261,144.0 C .. t ·~ ' ,• 1• •• Bond Reduction Cost--Quant Cost ·' $0.0 '$0.0 $0.0 $0.0 . '' ,. $1,600.0 $0.0 $1,600.0 $17,848.0 $5,354:4 $23,202.3 D E ---------------------- @ . Site Improvement Bond Quantity Worksheet : . -. . Original bond computations prepared by: Name: MELL. DALEY, PE Date: -· 07/21/2000 PE Registration Number: ---'1"'3:::25::,B::.._ ___ __;_ ________________ _ Tel.#: (253) 33~2200 Firm Name: DALEY-MORROW-POBLETE, INC. Address: 726 AUBURN WAY N. AUBURN.WA 98002 Stabilization/Erosion Sediment Control (ESC) Existing Right-of-Way Improvements Future Public Road Improvements & Drainage Facilities Private Improvements (A+B+C+_D) =TOTAL (T) PERFORMANCE BOND AMOUNT Column (A) (B) (C) (D) SITE RESTORATION BONDI · (A) (first $7,500 of bond shall be cash.) RIGHT-OF-WAY BONDI (B) PERFORMANCE BOND• AMOUNT. Minimum bond amount is $1000. TOTAL RIGHT-OF-WAY & SITE RESTORATION BOND .. ! (A+B) ...:::.S _______ _ (First $7,500 of bond shall be cash.) PERFORMANCE BOND TOTAL AFTER BONDI (T-E) ·----,------ REDUCTION••• NAME OF PERSON PREPARING BOND REDUCTION: ·NOTE: The word "bond" is used to represent any financial guarantee acceptable lo King Coupty. •*NOTE: KCC 27A authorizes bonds to be combined when both ar~ required. PUBLIC ROAD IMPROVEMENTS . ' & DRAINAGE FACILITIES MAINTENANCE/DEFECT I BOND.AMOUNT (B+C) X 0.25 = _$'------- •. Date:' --'-'------------- *-*NOTE: Per KCC·27A, total bond amounts remaining after reduction shall not be less than 30% of the or!ginal amount. Page9of9 · S:PU8L1C\LUSD1LUIS\8ond Quan Worksheet ,\,IC,:•: . ' Unit prices updated: 12/97 Version: 1/28/99 Report Date: 07/12/2000 - I I \ I ••• I .. ·1 I I I I \ ' I I I I I I I I I KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL STORMWATER FACILITY SUMMARY SHEET Development LA/l.<;ot-J ~l'.'. Date 06/28/0D Location SE ~ NE 14 ~Ee. 32.1 T2~N /?.. 5£ Wfvl ENGINEER Name 1-1 e-1.. 1.,. , ZIAL.e 'I" PE Address · 72~•-At.lWIW N, Developed Site: Acres 2 , D~ Nwnber of detention facilities on site: _!_ponds vaulis tanks DEVELOPER R1V1eRA Pt.. > I"! -6066 Number of lots · 14- Number of infiltration facilities on site: .. ·.· · __ .. _· ponds · · __ . _. vaults tanks ,\ .. ····~ -' ... Flow control provided in regio_nal fadlity. (give location) _________________ _ No flow control required Exemption number ______________ _ Downstream Drai e Basins Immediate: : Basin A BasinB BasinC BasinD. Number & type of water quality facilities on site: · ___ biofiltration swale (regular/wet/ or continuous inflow?) _,_ combined detention/WQ pond (WQ portion basic or large?) combined detention/wetvault __ compost filter _. __ filter strip ___ flow dispersion --farm management-plan ___ landscape managemeni plan __ sand filter (basic or large?) --·-sand filter, linear (basic or large?) __ sand filter vault (basic or large?) stormwater wetland __ wetpond (basic or large?) __ wetvault ___ oil/water separator (baffle or coalescing plate?) catch basin inserts: Manufacturer _________________ _ t,;,: ___ pre-settling pond ___ pre-settling structure: Manufacturer ________________ _ __ flow-splitter catclibasin DESIGN INFORMATION INDIVIDUAL BASIN A B C D Water Water ndVr 1998 Surface Water Design Manual I ., 9/1198 @) I I I I I I I I I I I I I I I I I I I KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL DESIGN TOTAL INDIVIDUAL BASIN INFORMATION, cont'd · Drainage basin(s) A B C D . .. .. Onsite area 2.. 06 ~c. Offsite area o.;; AC. T""" of Storaae Facilirv PaNI> Live Stora•e Volume 221 ~~7 er Predevel.;;;:;;, Runoff Rate : 2-vear 0.12~ ... . . ---· -10-vear . 0,'2 cp; .. . ... . --..... -... . .. . JCJO..vear o. 3SI CF' . Develo"'"" runoff rate . 2-vear 0,4, C.r=t-. .. ... . ' ' : 10-vear o.~4 Cf'.S .. .. ... ... -. .. ' ··JQO..vear 0. '114 CFS, . . --. T~ ofrestrictor. .: -. . .. Size of orifice/restriction ·No. I 1 Ve" 1 . .No.2 .• I'? fA,11 ' ·No.3 ; ~I/ ) No.4 . . .. . . FLOW CONTROL& WATERQUALITYFA.Cll.ITY SUMMARY SHEET SKETCH . ... ~ ' · All detention, infiltration and water qll8lity facilities must include a sketch per the follmving criteria: · · I. . Heading for the drawings should be located at the top of the sketch (top right-hand comer) .. . The heading should contain: · · • North ano,.; (point up or to left) • D9# __ • Plat name or short plat number. • Address (nearest) • · Date drawn (or updaied): • Thomas Brothers page, grid number .. . 2. Label CBs and MHs witli the plan and profile designation. Label the control structure in writing or abbreviate with C.S. Indicate whic_h structures provide spill control. 3. Pipes-indicate: Pipe size Pipe length Flow direction Uses single heavyweight line 4. Tanks-use a double, heavyweight line and indicate size (diameter) 5. Access roads • Outline the limits of the road • Fill the outline with dots if the road is gravel. Label in writing if another surface. 6. Other Standard Symbols: • Bollards:•••• • • • • • Rip rap 000000 · 000000 Fences -x-x--x-x--x--x~-. • Ditches -o--•o--•o--•o 7. Label trash racks in writing. 8. Label all streets with the actual street sign designation. If you don't know the actual street name, consult the plat map. 9. Include easements and lot lines or tract limits when possible. 10. Arrange all the labeling or writing to read from left to right or from bottom to top with reference to a properly oriented heading. 11 .. Indicate driveways or features that may impact access, maintenance or replacement 9/1/98 1998 Swface Water Design Manual 2 .. ( ® ~ ·: . ' ' . r· !. ;• l : ~<t<t . .} ,\·c·: \: ,'&> OVERFLOW STRUCTURE:_ TYPE' 11 • 48" W/CONE GRATE DEBRIS BARRIER. (SEE DETAIL SHT. 9) . RIM=450.50 1.E.=443.95 4.4LF 12"CPEP@ 1.'14i CONTROL STRUCTURE (SEE DETAIL SHT. 9) RIM=452.50 . I.E.=.444.00 : I 3 : . I: , . I: ~ ·," . I 6' CHAIN LINK·. FENCE I -----·- L .'! -~·-i ' . '. ,'.1 ); 1 M ., •'TW=451.7 : BW;,,444.0 '. ~ :·:·f.;.' .... ----- HAIN LINK FEN~E GAT (~E DETAIL SHT.\ 9) - 'IW=451.J BW=f44.I I I I s,.L 44.0 -- I 2) t~ ~E 1 - @ '~ ,, ':I q; .~ ---- I I ~ 444.4 8 WEST l I I .I ' :I I : I I 448.1: : I I I 449.6 I I I I I I I . ' ® ·- REMOVEABLE WATERTIGHT COUPLING - SCALE: 1• -J' PLAN . ' . . . ' ~ .. STANDPIPE ELBOW DETAIL N.T.S. ,,' ' A• •'':":: • . : . ROUND SELf'-LOCKING SOLID COVER------.._ MARKED •DRAIN• . 1 I -~ . REACH ROD P1PE SUPPORT(S): 3•x,090 GAUGE (TYP ) . BOI..Tm OR IMBEDOED 2• IN WALL..:______ . 1' (MIN.) LONG AT MAX. 3' SPACNG. MIN. 1 SUPPORT --... • ·' . ;.., ·: .. ' .· ~T. GRATE ~~f.'"C'-'':"'--f---J:.;.:.c.,;c·•:.·.;·~....:·:.• ;,· j, SPACE BARS O 4• O.C. 3" • ORlflC,C !a;l I E) 1 N'oTES: •. 4.~ 12• CPEP 0 1.1,JX OUT TO O'l'fRFLO!i: STRUClURE { CMP TO CPEf~' ADAPTOR 1. METAi.. PARTS: CORROSION RtslSTANT. GALVANIZED PIPE PARTS TO HA'JE ASPHALT TREATMENT 1. 2. FRAME ~ LADDER OR S1EPS OFFSET -SO A. CLEAN OUT GA lE IS VI SABLE FROM TOP. B. WMB-DOYl'N SPACE IS a.EAR OF RISER ;; 0 1>'. I' SECTION OF PIPE ATTACHED BY GASl<ETED BAND TO Al.LOW REMOVAL AND Q.£ANOUT GATE. r · ;·~1 3. IF METAL OUltET PIPE'CONNECTS TO :.0.. • •• ,,. ,,. .,. •• ,,. • . ... . . ~ CEMENT CONCRETE PIPE, OUll.ET PJPE ·.: .·· ·""· ·.,,.. · "" · · · :i,._. · ,,,,..': ·• • :_. :· TO HAVE SMOOTH 0.0. EQUAL TO CONCRETE PIPE I.D. LESS 1/4•. 4. MULT-ORIFICE ELBOWS MAY BE LOCATED AS SHOYtN OR AU. ON ONE SIDE OF RISER TO ASSURE LADDER CLEARENCE. CONTROL STRUCTURE No. 1 TYPE 11-54" ¢ . SCALE, AS NOTED ELEVATION NTS STANO. GALY. STEEL LADOER/STEPS (TYP.} U.2 IF 12• CP(p 0 -8.215" -=: I.E.•+4-4.00 ---'---------·· -··------- ~ -- I I I I I I •• ' ,· ·, .. I 1. ' I I I I I I I I I I . . . . ~~ . .. ~! ' ' ' ' .. .· .,.,, ...... . ' .,, . . .. ; . . ' · SECTION X .OPERATIONSAND · .. · . _ MAINTENANCE MANUAL -..... , '". . . ' . . ' . : : . . . ..... RESIDENTIAL ~ (RC) Resource Conservation ~ (R-1) Residential 1 du/ac ~ (R-4) Residential 4 du/ac ~ {R-8) Residential 8 du/ac [§J (RMH) Res!dentlal Manufactured Homes I R-10 I (R-10) Resldential 10 du/ac B (R-14) Residential 14 du/ac I RM-rl (RM-F) Residentlal Multi-Family IRM-T I (RM-T) Residential Multi-FamilyTradltlonal jRM-U j (RM-U) Residential Multi-Family Urban Center MIXED USE CENTERS ~ (CV) Center VIiiage luc-N1j (UC-Nl) Urban Center-North 1 luc-Ncl (UC-N2} Urban Center-North 2 [ED (CD) Center Downtown COMMERCIAL 35T23NA5~ 833 \ 1 J~ 2T22N R!;iE \ 1 T2 INDUSTRIAL ~ (IL) Industrial -Light 0 (IM) Industrial-Medium 0 (IH) Industrial -Heavy ----Renton City Limits ~ (CCR} Commercial/Offlce/Resldentlal --·--Adjacent City Limih ~ (CA) Commercial Arterial @] (CO) Commercial Office KROLL PAGE ~ (CN) Commercial Neighborhood PAGE# INDEX -•--' s CA ..,,. ~' RMH . . •..... I .. , I . . ....... . -R-8-__ J ·. -< f ,,--r .... ,-'-L __ IL _r; ___ ]_ ___ i R·B --~-------i ,-- _,15EIIIOII, R-14 ZONING MAP BOOK PW TECHNICAL SERVICES PRINTED ON 11/13/09 n.,<k><umonta,p,ptic"P'"""'"'""""' ru .. ·-"''""'"""'""'K\C'""'""""""" ........ -....... --... ,, ... __ ____ .. Crty __ _ .... H4 -29 T23N RSE E 1/2 (·-· 1 1 J4 -05 T22N RSE E 1/2 0 200 400 !!Sil I Feet 1 :4,800 .. i R-8 IIE1!'9"SI --- c········ ·····- t ------r--·-· R-4 ! .. L. 14 32 T23N RSE E 1/2 5332 ® King County Department of Development and Environmental Services 900 Oakesdale Avenue Southwest Renton, WA 98055-121 9 lMs~>J ~1<c l--ffPoo3 ,-rot0D ~LL-?~.s. S-_---·,o· -,'w, rATE-'R ·THIS POND IS !IN ,OUR CARE ,T . ' 'RM · .. t\ 1 ' ·· !. • . Runoff is stored and slowly released from this S--1· -, ·o-:R ___ A' --_ G--IE.-pond. This helps prevent downstream flooding · • . •. , '. ·. · , ' ' i . · · • ,' .• . . .. ~nd erosion and helps improve w~ter qu~lity on ----·_ ---its way to Puget Sound. For more inf ormat1on ON-, 'D---or to r,eport littering, vandalism and other 1 , • • .•• , _ . pro~~~ms , c~II : Department of Natural Resources Fac1ht1es Ma1nt,enance : 206-296-8100 . ® iLA.R SON PARK'E •