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<br />STUDY REACH 1 (UPSTREAM GOLDEN CITY lIMIT TO TUCKER GULCH)
<br />StudyReijchlisij5,500foot(1.2mile) segment of Clear Creek as it flows
<br />from the Golden City Limlt upstream of U.S. 5to its confluence with TuCker
<br />Gulch, a major tributary. Tnecreek is crossed in this reach by lJ.$. 6, a
<br />pedestrian bridge, \/ij,hingtonAvenue and ford Street. Tnis study reach lies
<br />entirely within the City of Golden, and land use ranges from parks and open
<br />space to residential, corrmerci.1.1 and municipal type land use. The City's
<br />water treatment facility, Library, City Hall, fire Department and Police
<br />Headquarters are all located in the floodplain.
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<br />There are tl<<J basic types of channel conf1guration, in stooy Reach 2. Be-
<br />tween Fora Street and the ColoradO ana Soutnern Railroad bridge there is
<br />approx lmately 2,600 feet of structural wal I~d cnannel. Tn i s channel, w! th
<br />concrete walh and a ndtural CObble invert has a flow capacity of approxi-
<br />mdtely 6,000 to 7,000 cubic feet per second. flowdurmgtnelOO-yearflood
<br />would be extremely unstable, however, because the steep slope of tne channel
<br />creates ~ lOry hi gl1 ve I oe 1t I es. Downstream of the C&S Ra il road br idge the
<br />channel bank configuration Change, from the vertical concrete walls to heavy
<br />rockriprapbanks sloping between 1:1 and 3:1 (Ilorizontal to vertical). The
<br />Channel bank riprap was placed by Coors Industries as part of tneir
<br />relocation dnd stabilization efforts along Clear Creek through their
<br />property. With few exceptions this channel haS the capacity to cMry tnt:
<br />lOO-year discharge of 13,470cfs.
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<br />Floodplain problems in Reach 1 include the disruption of the City's water
<br />supply by the washout and loss of the treatment plant's raw water holding
<br />pondS and shallow flooding Of the f11ter building. Aresidentidl area be-
<br />tween 9th and 10th Streets is subject to flooding by major events. The
<br />bridge at ~ashington Street is overtopped during the loa-year flood and back-
<br />water from this bridge causes flooding upstreOJl1 which affects th erecreation
<br />building, the library, al"ld the municipal building whiCh houses crHical faci-
<br />lities and equipment.
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<br />The agricultural and industrial water diversions from Clear Creek along thiS
<br />reaCh dre both nl.l1lerous and complex. Down,tre~ of Ford Street the Agri-
<br />cultural Ditch, the farmers Highline Canal and Coors lndustries maintain
<br />large d iver~ion heo:ldgates. Furtner downstreWl are 13 iversion \OOJr~s for Coors
<br />Industries, the iliannamaker DitCh, tne lee, Stewdrt ..nd Eskins DitCh, the
<br />Croke Canal. th€ Rocky i'buntain Ditch and the Mile, dnd ESkinsDitch .
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<br />The ford Street bridge is also inade~uate for the lOO-year flood and flow
<br />spredds out southward to inundate the Mi tchell School dncl affects se~er~l
<br />commercial bu1ldings. Downstream of ford Street, flood flowsWQuld inundate
<br />the mobile home area dlong the north bank dt Tucker G.ulch and affect the
<br />Coors\/ellness Center on the south side. A portion of the overflows on the
<br />south side flow easterly towards the Coors Brewery whiCh is locat ed in Reach
<br />2,
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<br />Probl er .'-eas ~ I on9 ~ea(n 2 i nrlude tne inad<:1quacy of the coocrete~alleG
<br />Channel tocarrytnelUD-year flow, which iscompound<:1dbythebackwateref-
<br />fectsofthepedeStrian bridges and the CrdwfordStreet and Vasquez Street
<br />bridg",;. Thi, resul ts in oyerbdnk flooding wh ich affects se~eral industrial
<br />~ tr lIC ture, in the Coors Comp I ex. Three aer i a I pIpe I ine cross i ngs would
<br />like 1 y be "e~ ert!cl by nigh vel oc ity lOO-year f low$.
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<br />STUDY REACH 2 (TUCKER GULCH TO MclN1YRE STREET)
<br />Studj ReaCh 2 encompasses most of the Adolph Coors Industries structures
<br />along Clear Creek and is the largest reach in the study area at 14,100 feet
<br />(2.7 miles). There are many crossings Of the creek in this reach: Vasquez
<br />:>treet, Crawford Street, tYoQ pedestrian bridges, the Colorado and SOutnern
<br />Railroad,CoorsBridgeNo. 3, and three aerial utilitypipel1nes. There are
<br />several dilll1s along this reach for agricultural and industrial water use, and
<br />numerous drop structures for control of the Channel slope.
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<br />STUOY REACH 3 (McINTYRE STREET 10 VOUNGF1ElO STREET)
<br />Thh reach, 9,400 f~et (1.8 miles) long, lS the least den'loped t'loodplain
<br />segrnentof tne study area. The only structures in this area are the Coor,
<br />Industr ies Commodities Tran, I oad bui laing, miscell anL"OUS gravel op~rat ions
<br />and an Jsphal t pav ing pl ant. The creek is cri/ssed by i'\; Intyr", Stre~t. a
<br />r al lri/ad brid~e serving the transload llui 1d1ng. lnterstate 70 and Youngfield
<br />Street. Two major water supply conduits croSS CleM Creek near Eldridge
<br />Street and provide water from Ralston Resenoir to Denver'; M::iffat Treatment
<br />Pldnt.
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