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HomeMy WebLinkAbout602292014 Drainage Report NTIENGIN-EERING& SURVEYING '. 11tSOUTH PEABOOYSTRE~T; PORTANGELES,WA9836( Engin,e.ers .Land Surveyors. Geologi$ts Con$tructlen inspection. Materials Testing , "jU LA-D 1,-$Q '9 . ' . ' ,1. INTRODUCTION , , : . -' . ' . , . " - ~ NTIEngineering and LandSurveying~ashiredby Forrest Tbwn,eto develop 'a drainage ' 'and 'erosion" control planfor his . proposed residential home site,at4t04 Dosewallips' R9ad,Jefferson CoLintyin Section 29, Township 26 Nonti;Range2WesfAsPC3rtof " this analysis, a' stormwatercoJlection, detention and conveyance, system, has been designed and a temporary, &perrltanenterbsion and sediment control plan has been prep(3red; for> t~econstructionof a private siogle family res i9ence, 'detached garage and driveway. ' , U. DESCRIPTION'OFSITE , '- ,\ , , . , Thls 2Q acre '16tis 100ated4 miles up the Dbsew~llips RJvef Basin near Bdnnon. The propertywascJearedin the Past and was replanted approximately l' 5 years~go,;, The , ' sitewlll remairlforested exceptforlheonepiusacre.tobe usedasttlebuilding ~ite. ,. The majority pfthe.Site.is'steepwjthJ()ck o~.tcrops,Th~.property. is bordered on the ' ,,"',nprthbyforestland,uordered . Qfl,the eastandwestbyprivatel0fsandonthesoU~h by, ' : [)o?ewaIHps Road.' ' ,.'. " . " . , . , . , , " ' ',Element#1 MatkClearingUniits .,,', ".,. ,. , ".,',.' " , ",."". ",> '"',, "",.: "'., " " 0 , The:ptojectsiteis ina'nisolated'area 4miles up the DosewalliPs;Hjver , BaSin ~'Jnadditiorl, the 'Sifejsforestland,onasteeprock~".site"'".The.", ',' ,,' in, ,s,ta"I,lati,o.n, b, fa, n"a, ,c,t,u,~, H,ence"",",iS"'im,,,pr,a,' ctica, ',I and", w,JII' 'C,', a,u, ,se"""",a,'".d",d, it,i",o, na,',], d,i,s, tur"~a,, n,c, e,', to,"".',t, h~slt,e., ,,:Th, e, c~,'n"",s"tructio,n b, 0, .,u,n,.'<:ta, Cry" a" "nd".. tree fI,'., ag, 9,i,il, g, ", c,', an,. De: accoQ1plisned just as'eff~ctiyely with coloredflagginQ, ,F()rexampr~;, '" " brig,htoran~eflaggingforthebolindaryand' bri~ht,.,pin,', k flci~,' ,,"', i~,'fOV. ,r, t,he",."",n<',.", .," trees. "', ,RE\j~l.,E ",' ".,J,EFf.fRSO.N.""C6UNTY ,',ntn" ~ Element#2"Establish Construction' Access o The construction access to the~ite wit! be'the same as the finahiiriveway a~cess. , " ,'. ',.' b, The driveways are alreadycovered,wittrnative gravel, whichrninimi4es .' debris 9ndsedimenl1eavirtg the site during construction, E,lemeRt #3 Control Flow Rates, , " " " .' <i 'ThisitemwiHbe'coveredin Minimum Re,quirernent#7: . , " "- Element #4lnstaIlSedil11entControls' , ,,','. t,' ,', '""".", " ' ~,Th$runofffrornJhedeveloped areawiHflowthrougha cour~eofcheck." 'dams", which:will'decre~se the velocity ~nd rtlininiizeerosionprior to " draining into the d€}tention pond: , " , , ,"', ,'" ",.' ,'0' Pond.berms ahddisturb~dar6'as willb~ seeded todecrea~e long term , erosion. .,,' . ',' " '". ,', To.min,irrJiZeerosionduring coAstructioh, wattle~ will' bt} installed" seef)lan' for lo~tiorianddetails;~ ' , , : " , o rhesoilcQveris prlmarily-cotJr~eaggre9atewithminirIlalfines. This, 'RaturaLco(1e:Htion wjJI'Jed~cetheerosiQn duringcqnstructipo., " , , Element#5Stabillze'SoilS ',' ,', " ", " 'oTb minlmiiethesoiferosionforces, ofrcllindroplmpact,f1owin9Y-'aterano , wind erosion, during consttuction,,;thecOntractorWnlfOllowthe:e?<pOsed, "". andunworked soil, sc~,edule'selpYPQEJoran soils Qnsite,FromOctOli>er ',. 'tthrou~hAptil3P, nasoilsshalr re91ain'exppsed and9riw9rf<ed fOot .rt)ore' ,than 2dqys, and from May,ttQ Septernb(ftr.30/no soils ShaUJE:)maiO ,', exposed:andunwqrkedJormorethan7days:,', , : " '" ,,', ".'""", ,"".'" An exposed soils. causedpy constru,ction.activi,ti~s shallbestapilize<fahd".'.. hydroseeded,or$o.ddeduponcompletioo;,oftheprojec~;';" . ',.,<..:; " ' , --: y '- . -' '--,..;- - '. ,-' ," -., ' ,., -'. , :' Elernent#7 ProtectiDrain"Jnfets ' " " ,,' 0' " ,;Q..the.catchh~shinstalled".during'G.on$tru~~ion'Shall beprotectetl from cdebrisandsedimentwitbfilterfabricaod/or~()1i(:jcovet~,. . 0' ",:Two culvert~existunder'DosewalUpsR()ad1 which drainstorl11w~tet:'from, the north sideofthe" road, fothesou!hsideof ttie..road ,'sndthen'scross the < '. jowlaoddowntot~ DosewaIJips,River.' These cUlverts,aswel,ICiS the' ' "; "', axis, t,i,ng..'.,ro,a" d, s"i"ded"it""Chs""h",all"',b"e".",,kept,.,c,,Ie,ar,', O"""f,.de,b.r,is,a,n,cd"".,se,',' ."d,fm,' ',e,n,t.:, .' ',',' ',,', , ; '. ',b,' .'AU""',ca";tc,hbaSif1,,S,culv~rts,,, ',an, d"",d""rain, ',a, >9, e,r"o",' ufesWill;beins~,', '.', ".".I~".",'.,,"~." 'y'..',E,,' ,""D~.," .' , once a week'anddaifydurlng astqrme'itent. . .',K~\tj~,lV'. ," '., ." ~. ,.;' , Element #BStabilize Channels and Outlets o "The existingdrainageoorridors beyond distqrbedateasWill be maintained during and aftertonstructiorlwith'native vegetation.," "". . a The pond and drainage ditcheswiUbe~arniorf3dwithnative rocks to preventerosion.~ , - , \', ; '.' ' Elemant#9 Control Pollutants " ,,' " ,. " '.', ".,' ", ",.,' ,," a,.AII chemicals,liqqidprodlJcts, petroleum products and non-inert wastes present ,on site, shall be covered;'containedandpfotected from yatldaHsn;) , .' and handtedin a manner to minlmizecontaminalionof stormwater. a To'minimize Pollutants, generatedoyheavye<:1uipry1entandyehicle$;' aU, maintenance and repairssh~ILbecondqcted using spill prevention .",'measures suchcas drip Pans: , , '.' , '. ElemEmt#tOContr(1IDe-watering .,., ' " '" ," ,', ..".,.' ,'," ," ' alf de~wateringisrE}quireqduring,construc1ionandthe de~vvatering\V~te( , has similar characteristics 10 storl11water runoff,it iSt6bedjrectedacro$s the.cleared site', area and infiltrated on site. " ."." ,.". ',' ", ,."", ", ,,'," ~' ' . :,Curtainarainst;>ehind the building ,foundations :and.vaults shaUbedIrected through 'separatecoUectiOnang .di~posalpipesandJ)e>dayllghtedintoa"" " .',',. ar~ored, & vegetated ditCh , Se,ction: , to be weUestablishe(j andwithtime wiU-c6htinuetg thicl<en.~ndbecomemQre dense. Only a Small area ,of the35-~cre site wiUbe disturbed:' All disturbed ' greas other than the building sites and driveways wiUbereseeciedand ' maintained in a natural state. LandscapiFlg:wiU be wit~hativeplants~- , - . , . Minimum Requitement#4PreserVatiori of Natural DrClihageSystems andOutfaHs ' '. Theexisting.drainage-rOLJteis via two~ulvertsthatcrossuhderDQsewallipS,Road. at approximatejythecenter ofthesouthpropertYline.ThestormwatetwiUbe,' ,:' - detainedbn siteand relea~edCltthepre-developmentretain into the existing , drainage route. . ' Jf.fffRSDN.",'COUNTV',oea. each stormevent,the first requiremeht ofb pe ration and maintenance ofth,e . stormwatercorlection system ,co,ns,istsofensuringfree flowing catch basin,' , coUectionlinesand outlet, as weU a,s, maintaining the 'man-made' conveyance ' "outlet pipe. Thesystertls~hduld' be checked and cleaned regularly of debris 'and sediment. " ", , ' · The main concern with pontf design is the riskQf blowout Thepohdhasbeen designed withminim,alabove ground construction to, decrease .the,fisk. of. b, Jowo"u,ts" .Ifth, e"p,o, n"d,',is. ,da,m,a,ge,d~,th,e, , p,O"n,d nee,d" $,' to."~,,e. ',re,p""a, i,""e,dim, m, e"'d"."ia",,te,',I,Y to preventoffsite, downstream damage from occurrIng, and thedesign~ngin~r ' , neeas to be consulted to prevehtfutUre blowout, s.' .,' ,_' i-'. . ',- " .,' ;- _, , ,'Jhe ,first step in impl,ementing this. plal'lis prepadng tbesltein ~Cc9f'danG-ewith .DOE ' .guidelines..." The. clearing limits ',and trees withio'the, Cleatinglirnits that are to remain " shall be, clearly'matkedwithflaggiI19, ",fn:8dditJdo,to lTli~imizeerosioncau$iJlgland , " .,'distur.bing'activWes~a wattleshaU beinstaHeddownslope. ofaUconstrJJction,seerpl~ii.' forlocation~. ,~It, is,the.owner's,. responsibility to maintain aCleanroadw<;tyin'.acc.ord?nce, " with'.theJefferson.Covnty P~blicWorksDepattment regulations. The~tandar(fwattle' · ' . detail,is provitfedohthe,plan. ' '. ',' , , J . . ,c " Jh~,n~xt~episdirec~ingd~veldPrnentrlJnoff. 'T,he,bQildinfJ'rundffWillb~~dUeC~edYi~l , ',". ,.,gptt~r.sand'dQwnSPPuts,w11ich.WiU drainJhtQ underground6"'diamet~rASrM.p~o.3a ...," ': " ,pipj,ngSloped,at 1%rrJinimlJm., Thepipingfrom the home win drainiflt6tb~uJ:>pef>" \i" ,." ,cdri,yewa}{ditch '" This driveway wilLs lope towardstheditch~r~%,and:checkQarnswiUb,eo' ' ., "\ iri~~aUedintheditch'eV~IY 50feet.Th~ driveway's .slope,jsa'pprmdmately.18%'anctthe: .'checkdsfTls'will $loWdowf1therllnoff. .lhe' constru~tep.,~itchWl.Udrainjnto,anexf$til;l9' ". " ,dFa'inage corridor''NhichWill draiT(into thepqnd.Thef3ipingfrorrr the gatage)Nill drain. 'direcUyinto ,the pond, :and tnelower driVewa.Y,will be sloped to'd~8inintoP9rid. 'Ttl~ lJplan~ ruhoffcuttingdown tnr()ughthe'pehter of thesiieV/iud~aiflint()the:p~rl9~, ".' Tnedrainage route crosses the upper .ditcM~nd 'Qoth, driveways. CulvertswiUne~dJp< . bein$taUedLind~rthe driVeways 'and ditch line. ' . , I . ..~ Tnepond ,has,been"sized.f~r the,.,.100 ,year". 44 ',.hour storm even~. '..'ThePQDdJNi.ll.b~ . ,:/urilinedtoaUow fOfQn"site ihijltratiqn. .,", Therefore,'inijltration is an effeclivepoi!uti()f"r c" botrol measure.' Therul10ffwiltbe released' via~acatch basio,withan orific-ean,dweif " ".discharge,controlpl~te:..Theoiifjceand.weirsiz,earedetaile~fOllthe'plartThe',i. " ,.' discharge from the pond will be released into 'ifJe DosewaflipsRoadnortherly'road$id~" ,'. , , ' , ,'ditcn';~, Thenortheriy ditch' drain's vla'twpcLlIyertsunderDOs~wampsRoadtothe so~th ';, ",' " - - , " " ", siQe of th~roa?TheJimoff'drains,across thelowerlle'igbbor'spropertyRECEIVED Dosewalhps "wer. ' ',' .,' , '. ',,', .,: ','... "'.' ,... " ' '., ',' f' .6,' , ,JEffERSON'cnUNlln&U~, , . . The lower neignoor's field ,is a Jocal depression~ Theprpperty ownerstated,the"irfiel,d . floods e.verystorm, event and then dissipates quickly once' thestdrm haS paSsed. ,This ' is, a 'historical, eve,htandhas been~happening for.generatfons. , ' , Acopy oftheWestern Washington Hydrology Model ieportsfor this property and the '.' . plan are located in theap"pEmdix. ' " , . , " , - - - . - -' , . This ,report hasb~en preparedfortheexclu~i\le us~of Forrest TOwne for hJs ,proposed <" , ct;>nstructionofa privatehome;'"The recomrnentiations inttl'e' report apply only to the " prQpertythatwas:examinedan~theyarenolapplicabletc;>otherlo~ations.. The".", , investigation and reconirneridations'contained:in,this, reporfare;basedupon,'site,cohai;., , lions as they existed'althe time'C)fours,iteinsPectlons.DuringCQhstruction"if " " , subsurfaGeofother,conditions ,are dis<ro"eredthat :,are.sigllificanUycUfferent'from'those descriQedintfle'l"epbrt, NTI;shouldbe advised at once S'o thatweyan revie'vVthe: , .. ,. c<?nditions, ah~reCOnside(ourr~cOrnrne~~dgti~ns;,,~her-e necessarY.: Unan'ticipated~oil con~itions Cil{e'c()mmo~lyencqunterett onppnstructionsites", especiallywhetl m~ , ,,' t{)pogfaphYhasbe~n.aitefeqye.a.rs 'agq.'&uchunexpected.C00ditions.frequeritly requite. , , ,thata<;fditi<:>oatexpenditurespe,ma,de'to: attaitJaprop~r1Yicon$tructed.proj~et.'We " , ' recQRlmendthatacontingencybe ~sta~Ushed inlhe:'projectbudget.and$PtleduleJo . G()ver~rte,x, ,pectedconditi()I)~. ' ' , , . WESTERN WASHINGTON HYDROLOGY MODEL V2 PROJECT REPORT Project Name: Site Address: City Report Date Gage Data Start Data End Precip Scale: default 9/14/2007 Quilcene 1948 1993 1.44 PREDEVELOPED LAND USE Basin Flows To GroundWater: Land Use TILL FOREST: Basin 1 Point of Compliance No Acres 20 DEVELOPED Basin Flows To GroundWater: Land Use TILL FOREST: IMPERVIOUS: LAND USE Basin Pond No 1 1 Acres 19.55 0.45 RCHRES (POND) INFORMATION Pond Name: Pond 1 Pond Type: Trapezoidal Pond Pond Flows to : Point of Compliance Pond Rain / Evap is not activated. Dimensions Depth: 4ft. Bottom Length: 148.27ft. Bottom Width: 29.65ft. Side slope 1: 0.5 To 1 Side slope 2: 0.5 To 1 Side slope 3: 0.5 To 1 Side slope 4: 0.5 To 1 Volume at Riser Head: 0.321 acre-ft. Discharge Structure Riser Height: 3 ft. Riser Diameter: 18 in. NotchType Rectangular Notch Width: 1.310 ft. Notch Height: 1.228 ft. Orifice 1 Diameter: 7.137 in. Elevation: 0 ft. Stage (ft) 0.000 0.044 0.089 Pond Hydraulic Table Area (acr) Volume (acr-ft) Dschrg{cfs) 0.101 0.000 0.000 0.101 0.004 0.282 0.101 0.009 0.399 Infilt{cfs) 0.000 0.000 0.000 0,/ tf il:~ I /1SS ~~' ~~ ,------- --- '18 ~75(Z ( tIlO . 'lJ>6 ,------=-; n'\f) ':,(' t-l~~ lSC ::,t:> I RECEIVED OCT 2 6 2007 JEFFERSON COUNTY DeD 0.133 0.101 0.013 0.488 0.000 0.178 0.102 0.018 0.564 0.000 0.222 0.102 0.023 0.631 0.000 0.267 0.102 0,027 0.691 0.000 0.311 0.102 0.032 0.746 0.000 0.356 0.102 0.036 0.798 0.000 0.400 0.103 0.041 0.846 0.000 0.444 0.103 0.045 0.892 0.000 0.489 0.103 0.050 0.935 0.000 0.533 0.103 0.054 0.977 0.000 0.578 0.103 0.059 1. 017 0.000 0.622 0.103 0.064 1.055 0.000 0.667 0.104 0.068 1. 092 0.000 0.711 0.104 0.073 1.128 0.000 0.756 0.104 0.077 1.163 0.000 0.800 0.104 0.082 1.197 0.000 0.844 0.104 0.087 1. 229 0.000 0.889 0.105 0.091 1. 261 0.000 0.933 0.105 0.096 1. 292 0.000 0.978 0.105 0.101 1. 323 0.000 1. 022 0.105 0.105 1.353 0.000 1.067 0.105 0.110 1.382 0.000 1.111 0.105 0.115 1. 410 0.000 1.156 0.106 0.119 1. 438 0.000 1. 200 0.106 0.124 1. 465 0.000 1. 244 0.106 0.129 1. 492 0.000 1. 289 0.106 0.133 1.519 0.000 1. 333 0.106 0.138 1. 545 0.000 1. 378 0.107 0.143 1. 570 0.000 1. 422 0.107 0.148 1.595 0.000 1. 467 0.107 0.152 1.620 0.000 1.511 0.107 0.157 1. 645 0.000 1. 556 0.107 0.162 1.669 0.000 1.600 0.108 0.167 1. 692 0.000 1. 644 0.108 0.172 1. 716 0.000 1. 689 0.108 0.176 1.739 0.000 1. 733 0.108 0.181 1. 761 0.000 1. 778 0.108 0.186 1. 785 0.000 1. 822 0.108 0.191 1. 854 0.000 1. 867 0.109 0.196 1. 952 0.000 1.911 0.109 0.200 2.068 0.000 1. 956 0.109 0.205 2.200 0.000 2.000 0.109 0.210 2.344 0.000 2.044 0.109 0.215 2.498 0.000 2.089 o .1l0 0.220 2.661 0.000 2.133 o .1l0 0.225 2.831 0.000 2.178 o .1l0 0,230 3.009 0.000 2.222 o .1l0 0.234 3.192 0.000 2.267 o .1l0 0.239 3.380 0.000 2.3ll o .1l0 0.244 3.573 0.000 2.356 0.111 0.249 3.769 0.000 2.400 o .1ll 0.254 3.969 0.000 2.444 o .1ll 0.259 4.172 0.000 2.489 o .1ll 0.264 4.377 0.000 REC'EIV'ED 2.533 o .1l1 0.269 4.584 0.000 2.578 o .1l2 0.274 4.793 0.000 2.622 o .1l2 0.279 5.003 0.000 OCT 2 6 2007 2.667 o .1l2 0.284 5.214 0.000 2.7ll 0.1l2 0.289 5.425 0.000 2.756 0.1l2 0.294 5.637 0.000 2.800 0.1l3 0.299 5.874 0.000 JEffERSON COUNTY oeD 2.844 o .1l3 0.304 6.130 0.000 2.889 o .1l3 0.309 6.391 0.000 2.933 o .1l3 0.314 6.656 0.000 2.978 o .1l3 0.319 6.927 0.000 3.022 o .1l3 0.324 7.120 0.000 3.067 o .1l4 0.329 7.341 0.000 3.ll1 o .1l4 0.334 7.647 0.000 3.156 0.1l4 0.339 8.019 0.000 3.200 o .1l4 0.344 8.446 0.000 3.244 o .1l4 0.349 8.922 0.000 ':l ?AQ n 1 1 c:; n ,:\C:;11 Q 11111 n nnn 3.333 0:115 0.359 10.00 0.000 3.378 0.115 0.364 10.60 0.000 3.422 0.115 0.370 11.23 0.000 3.467 0.115 0.375 11.89 0.000 3.511 0.116 0.380 12.59 0.000 3.556 0.116 0.385 13.32 0.000 3.600 0.116 0.390 14.07 0.000 3.644 0.116 0.395 14.86 0.000 3.689 0.116 0.400 15.67 0.000 3.733 0.116 0.406 16.51 0.000 3.778 0.117 0.411 17.37 0.000 3.822 0.117 0.416 18.25 0.000 3.867 0.117 0.421 19.16 0.000 3.911 0.117 0.426 20.10 0.000 3.956 0.117 0.432 21.05 0.000 4.000 0.118 0.437 22,03 0.000 ANALYSIS RESULTS Flow Frequency Return Return Period 2 year 5 year 10 year 25 year 50 year 100 year Periods for Flow(cfs) 3.563807 5.426954 6.950793 9.248324 11.258139 13.548411 Flow Frequency Return Return Period 2 year 5 year 10 year 25 year 50 year 100 year Predeveloped Periods for Flow(cfs) 3.218126 4.826032 6.045071 7.766019 9.182865 10.718503 Developed Mitigated Yearly Year 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1 Cl7 f) Peaks for Predeveloped and Developed-Mitigated Predeveloped 10.681 3.695 4.220 3.329 3.850 4.680 5.224 17.964 3.230 5.777 5.784 3.402 4.996 3.815 3.336 2.488 1. 567 10.936 3.886 3.631 2.918 3.468 5.297 3.849 3.645 5.178 3.800 4.7/0 Developed 9.834 3.084 4.115 3.271 3.665 4.687 5.226 12 .725 3.268 3.170 5.708 3.303 2.891 3.510 3.425 2.059 1. 559 6.935 3.968 3.591 2.772 3.477 5.419 3.529 3.670 4.516 3.588 4,'')04 RECEIVED OCT 2 6 2007 JEffERSON COUNTY DeD 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 2.616 2.933 2.962 3.802 2.880 2.978 5.723 1.661 2.624 3.054 3.862 2.651 1. 495 2.061 4.129 3.617 2.275 2.609 2.584 2.949 2.246 2.003 1. 939 5.570 1. 343 1. 866 3.035 3.120 2.271 1. 387 1. 622 4.198 3.673 2.202 Ranked Rank 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 Yearly Peaks for Predeveloped 10.9359 10.6814 5.7844 5.7770 5.7226 5.2968 5.2235 5.1776 4.9963 4.7199 4.6797 4.2195 4.1292 3.8858 3.8624 3.8499 3.8490 3.8152 3.8022 3.8003 3.6947 3.6453 3.6312 3.6173 3.4680 3.4020 3.3360 3.3287 3.2299 3.0535 2.9780 2.9621 2.9331 2.9183 2.8805 2.6513 2.6239 2.6157 2.4879 2.2750 2.0607 1.6607 1. 5670 1.4954 Predeveloped and Developed 9.8341 6.9352 5.7078 5.5704 5.4188 5.2256 4.6874 4.5158 4.5041 4.1984 4.1151 3.9675 3.6726 3.6699 3.6654 3.5907 3.5877 3.5286 3.5100 3.4770 3.4252 3.3034 3.2714 3.2683 3.1695 3.1198 3.0843 3.0352 2.9487 2.8911 2.7723 2.6088 2.5840 2.2714 2.2456 2.2015 2.0592 2.0030 1. 9387 1.8655 1. 6223 1. 5588 1. 3874 1. 3433 Developed-Mitigated 1/2 2 year to 50 Flow (CFS) Predev 1.7819 2040 1. 8776 1709 year Final 1949 1610 Percentage Pass/Fail 95.0 Pass 94.0 Pass RECEIVED OCT 2 6 2007 JEFFERSON COUNlY OeD 1.9733 14i4 1342 94.0 Pass 2.0691 1186 1110 93.0 Pass 2.1648 984 945 96.0 Pass 2.2605 818 788 96 .0 Pass 2.3562 687 673 97.0 Pass 2.4519 571 554 97.0 Pass 2.5477 459 468 101. 0 Fail 2.6434 383 386 100.0 Pass 2.7391 324 325 100,0 Pass 2.8348 276 283 102.0 Fail 2.9305 247 240 97.0 Pass 3.0263 211 213 100.0 Pass 3.1220 188 181 96.0 Pass 3.2177 166 158 95.0 Pass 3.3134 137 131 95.0 Pass 3.4091 116 110 94.0 Pass 3.5049 96 89 92.0 Pass 3.6006 82 69 84.0 Pass 3.6963 65 55 84.0 Pass 3.7920 55 45 81. 0 Pass 3.8877 43 42 97.0 Pass 3.9835 42 36 85.0 Pass 4.0792 35 34 97.0 Pass 4.1749 31 29 93.0 Pass 4.2706 27 26 96.0 Pass 4.3663 26 24 92.0 Pass 4.4621 25 23 92.0 Pass 4.5578 22 20 90.0 Pass 4.6535 20 18 90.0 Pass 4.7492 18 15 83.0 Pass 4.8449 18 14 77.0 Pass 4.9406 18 14 77.0 Pass 5.0364 14 12 85.0 Pass 5.1321 14 12 85.0 Pass 5,2278 11 11 100.0 Pass 5.3235 9 11 122.0 Fail 5.4192 9 10 111. 0 Fail 5.5150 9 10 111.0 Fail 5.6107 9 9 100.0 Pass 5.7064 9 8 88.0 Pass 5.8021 5 7 140.0 Fail 5.8978 4 7 175.0 Fail 5.9936 4 7 175.0 Fail 6.0893 4 5 125.0 Fail 6.1850 4 5 125.0 Fail 6.2807 4 5 125.0 Fail 6.3764 4 5 125.0 Fail 6.4722 4 5 125.0 Fail 6.5679 4 4 100.0 Pass 6.6636 4 4 100.0 Pass 6.7593 4 4 100.0 Pass 6.8550 4 4 100.0 Pass 6.9508 4 3 75.0 Pass 7.0465 4 3 75.0 Pass RECEIVED 7.1422 3 3 100.0 Pass 7.2379 3 3 100.0 Pass 7.3336 3 3 100.0 Pass 7.4294 3 3 100.0 Pass OCT 2 6 2007 7.5251 3 3 100.0 Pass 7.6208 3 3 100.0 Pass 7.7165 3 3 100.0 Pass JEfFERSON COUNlY DeD 7.8122 3 3 100.0 Pass 7.9080 3 3 100.0 Pass 8.0037 3 3 100.0 Pass 8.0994 3 3 100.0 Pass 8.1951 3 2 66,0 Pass 8.2908 3 2 66,0 Pass 8.3866 3 2 66.0 Pass 8.4823 3 2 66.0 Pass 8.5780 3 2 66.0 Pass 8.6737 3 2 66.0 Pass R 7hQl1 "< ? hh n p;:::.c::::~ 8.86S2 3 2 66.0 Pass 8.9609 3 2 66.0 Pass 9.0566 3 2 66.0 Pass 9.1523 3 2 66.0 Pass 9.2480 3 2 66.0 Pass 9.3437 3 2 66.0 Pass 9.4395 3 2 66.0 Pass 9.5352 3 2 66.0 Pass 9.6309 3 2 66.0 Pass 9.7266 3 2 66.0 Pass 9.8223 3 2 66.0 Pass 9.9181 3 1 33.0 Pass 10.0138 3 1 33.0 Pass 10.1095 3 1 33.0 Pass 10.2052 3 1 33.0 Pass 10.3009 3 1 33.0 Pass 10.3967 3 1 33.0 Pass 10.4924 3 1 33.0 Pass 10.5881 3 1 33.0 Pass 10.6838 3 1 33.0 Pass 10.7795 2 1 50.0 Pass 10.8753 2 1 50.0 Pass 10.9710 1 1 100.0 Pass 11.0667 1 1 100.0 Pass 11.1624 1 1 100.0 Pass 11.2581 1 1 100.0 Pass The development has an increase in flow durations from 1/2 predeveloped 2 year flow to the 2 year flow or more than a 10% increase from the 2 year to the 50 year flow. Water Quality BMP Flow and Volume. On-line facility volume: 0 acre-feet On-line facility target flow: 0 cfs. Adjusted for 15 min: 0 cfs. Off-line facility target flow: 0 cfs. Adjusted for 15 min: 0 cfa. program and accompanying documentation as provided 'as-is' without warranty of any kind. The entire risk regarding the performance and results of this program is assumed by the user. AQUA TERRA Consultants and the Washington State Department of Ecology disclaims all warranties, either expressed or implied, including but not limited to implied warranties of program and accompanying documentation. In no event shall AQUA TERRA Consultants and/or the Washington State Department of Ecology be liable for any damages whatsoever (including without limitation to damages for loss of business profits, loss of business information, business interruption, and the like) arising out of the user of, or inability to use this program even if AQUA TERRA Consultants or the Washington State Department of Ecology has been advised of the possibility of such damages. RECEIVED OCT 2 6 2007 JfFFfRSqN COUN1Y OCD Yearly Peaks for Predeveloped Flow Frequency Chart YEllR fl 11.26 o~.. x~dtf_ Yearly Peaks for developed W/O Pond - 100 Duration Graph Yearly Peaks for Developed W/Pond RECEIVED OCT 2 6 2007 JEffERSON COUNlY OeD