|
<br />i
<br />,
<br />
<br />f:. I rri!!:3t;on F:tcilifie~
<br />
<br />lrrigatiotl reservoirs and ditches within the stud;. area are lbled in Tabk 7. :>Vlajor irrig"tion
<br />reservoirs und dilChcs arc shown on Figure 9. lrrig<ltionrcscrvoirson record in the SED with.inlhc
<br />sllldy area iuclude Erie Lak.... YlartCll Lakes 1'0. \ and 2, Prince Lakes No. ! and 2. and Thomas
<br />Reservoir. A review of design r<:<:ord, in Slate !:nginco:r.; Office. the physical!",a!ion elf the
<br />t'\:scrvoirs within the calchments, und the ownership of the rcscrvoi rsindicaten"'\eofthcrescrvoirs
<br />store significant volumes of stonnwater and none were candidates for d~1cntion, SEO records
<br />indicatcPanamaRcscrvoir,I()cattxlaJjaccntlOlrn:oonhcrnpropertyholltldaryoflhcSlud)'area.is
<br />unlikdy to overtop and spill into the slUlly arc" during a lOO-ycar event. and il Ion was excluded
<br />from th~ hydrologi~ modd.
<br />
<br />TlIhle7.lrrigationFacilities
<br />
<br />R"""r',,,irorlrrigation Location! Source Decreed I:sc
<br />!)itch ori~i~:i ~:pacit...U
<br /> (Seclion ac-ftor.cfs\
<br />Re.""r'.'Oirs
<br />ThumasRcs~f\'oir "
<br />Prin~~ l.ake (Res.) '\0. 1 " S()\>lh BouldcrCr~ek '00 DunlC,li~
<br />Prirn:c Lake N(), 33 S()UlhBouldcrCrcck 83 Irrig:ltion
<br />Erie Lah (R..".,,-yoir) " South B()ulder Crc~k m Dome,tic
<br />ElmwuudRc,cr.."ir 26 South Boulder Cre~k 170 Irri~alion
<br /> (abandonell)
<br />r>.larf"dILake\.o, I 26 SUUlhBould""ICrcek " Irr;gation
<br />M~rfell L~k~ \:0, 2 , 26 SUUlhBoulderCre,k ,-
<br /> -,
<br />--j,ri7;atioIlDilchcs
<br />I.eggett " lJ()ulderCreek JU5 Irrigation
<br />Buulder~ndWcldC() IS Iloulder Crc~k 61,9 Icrig"ti,,"
<br />L()wwElultlder " Boulder Creek 10347 lrrigatioll
<br />t.~}nerC\)noawo",INo. 1 30 ~uulh lloulder Creek 30,{)o Irrigati\",
<br />SUllth[lol1lderCanyon T1S,R70WS"".9 Suuth Boulder Cr~ek 370,74 Irrig;ltiun
<br />Gu<>dnue TIS. R69W 5et.::l South Boulder Creek 30.31 Irrigation
<br />Howell , Boulder Creek 'I(LlO Irrigation
<br />fjowdl Beasle} 10 RoulderCreek 28.80 Irrigation
<br />BeaskySlough , (Seepage) 3.00 Irrigation
<br />Young 11 R<,throckSluugh 2A8 lrri~\t~\n
<br />Ar,hulelaSe"page " Cc\alCreek 1().I~) lrrigatic\n
<br />Chenault Drainage " (Drainage) 2.50 Irrigation
<br />Chenault Drainage \:0, 2 26 (Drainage) 1.00 rrrigat~ln
<br />Chenau1tVia,te " I (Waste) 5_75 Irriil"I;UIt
<br />McGinn TIS, K7()WS~,. " S"uth Boulder Cr~ck 1406 Irrigat;on
<br />Dry Cr""kD,wid"-ln liS R701'.,'s.,,,_ '" ""uthf-lnuldcrCreek 42.b6 Irrigation
<br />\hrth"",1..\hthcws " B<.\uldcrCreck 4,60 I Irrigatil1n
<br />frankR, Dufr,-P;oeline :t tSeenac.e) 0.50 Im'.ation
<br /> -
<br />
<br />LDcateuw,thmT(lWnsh,p I "Dlth. Ra"fle6<l \\'<'St links' 'I'C"hed olherw"e
<br />.. R""er.-v;r,inac-ltlrrigJtim,DilchN;nd;;
<br />
<br />.
<br />
<br />llllen"cptiol1 vr sl<>rnlwaH:r l]\Jw, by' "n Irrigati\Jn ditch can r~,uh in tlovding at lInprcdictJ.bk l(\~"tion,
<br />along the pmh uf toc ditch. The h~'<lrolol!-ic analysis assum~s irrigation dilCh~, ar~ !lowing full duting ~11
<br />cvcntsandtbcditchc5neilhercapturenortran,porlSHlrmwater.
<br />
<br />F. Off.SitcC~lehment'
<br />
<br />Fluod hydrographs ofcatchm<:nts discharging into toc ,tudy arca were analyzed using a vanety of melhucts.
<br />Bullhead Gulch/Prin':e Tributary discharging owr High",ay 287 "as modded in a 1992 study U\ctvanc<:ct
<br />Scicnces. Inc.. 1992) using CUHP-generated hyJrngraphs routed with UDSWlvt. TIlt; 1992 existing and
<br />futltre perc~nt imrcrviousne,;s models were used to gene",te oft~sitc flow, crossing Highway 2~7 for the
<br />current study with minor modi!ication.~. These modification, indude; 0) the pere~nt imperviollsness was
<br />changed in both modeb to rd]cct eurrent exi~ting and proj~e!cd land l'*S. nnd (2) the regi<lnal detention
<br />pond at Indian Peaks Subdivision uscd to ddine hydro]ogle eonditiollO forthcrccentFlSstuJY'lfBu\\hcaci
<br />Gulch (Taggert Engineering A~sociat~,. Inc.) was incorporated into both models. Off-site catchments OSI
<br />(Design Point 1060. tributary to Boulder Creek) and 052 (Dcsign Point 400, tributary to Coal Cre~k) were
<br />over 200 acres in area and "-er~ modeled u~inl! CL"lIPF. OtT-site calehm<,nls 410 (trihutary to Coal Cre~k)
<br />and 200 (lributary to Bullhead Gulch/Prince Tributary) were m()dd~-<l as catchment e]el1l<'nt~ in the
<br />CDS\V\I hydrologic mode!, Hydrologic model data input tor ofl~sit~ catchments are ~ound in ^ppendix A.
<br />
<br />G. Re,ults
<br />
<br />Flood peaks for lhe O.4-inchand the 2-. 5-. 10-. 50-. and 100-yearfloodev~ntsaresllmmari7ed in T..hlcs 8
<br />and 9 f", selcctcd design points SOO"'TI on Figures 2a. lh. lc and 3 in Chapter ll. These tahl~s indude
<br />cumulative area and pt:Tc~nt impc1"\'iou5 at eaeh design point and ar~ organi?cd 11)-" ma~i<}t wu(ersh~d and
<br />Cat~h01em. A comparison of cxLiting and future h.ydrographs for the 10- un<.! lOO-y~ar stann eve'll at
<br />selected design points are ~hown on Figure Hl. Th~ n~'dro\ogic analy~i5 indicate, dewlopment will ;ner~a~
<br />Ihe fll<lgnitude of f1()od reak~ lor all e\'cnts.
<br />
<br />
<br />~
<br />
<br />t
<br />
<br />___,',C"
<br />--.'~'" ~
<br />'~- -',- .....' ",-
<br />.....'"c.'~"'"',',.
<br />-,~~'~.a ~-,,:~~. '~."
<br />~--,. ,
<br />- .
<br />- "'
<br />- . .
<br />'. '~. .-
<br />
<br />1l1.4
<br />
|