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<br />(I )AAKANSASRIVER, PUE13[;O,COteRM>'Q."P~Qjemf@raqulltiGlec()systt)mr(1$-tl!!liIl#on,
<br />AFkansas Rivt)r,'Pt;rt!\b1o,,'CO\ll!lraa6'., ," , , ., ,.' ".,.. ';
<br />(2}J3'A YTIlEN DlVE~SreNP;R,:~;T'EtT, y ~.A:Rrv:lE~;CQi]'0~e,- PlrQjeete@JJ'.a~Gl
<br />ecosystem restoration, Hayden :Diversion Project, Yampa River, Colorado "
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<br />N(1lR,THF(i)1m;Gt:r~NlS'0NmYEn,p~~1JfjJ:{f't. 'i:I:ie1?:rI;1JJj~t .is",i;1!hi;~Cliit()~!JGli'Y'S 31'(1'Ci'Yl$gressi~\l.~t
<br />DistriGlt. ThespOnSi'Yr 'isttIe N@1'thF'0Jik Ritvel;IiU1pl'Q\iemeutJ~!fs0l:l'ila:ti@n;~_).
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<br />Loql{tiOl),Setting",aftd Problent;]J\lsl:fi:tAti~;n.Tliei,pt@je~tr~ae'l;11'sXo,~ate.~()f1i;tae NOFfl1Foi!kofta<7!~~ts()n
<br />IDverillnorthwestel1lGunnisonandea:stemFJelta .G0Uil.tieswmalwe~t.ceu~lli10etlI\lI<(d@,oao,0tlt~~Gi(~1~ t '
<br />westofIDeI1ver.ThepFoJect areal'ieswitllina 1;f4ffilerea~n:ih~evi~Ihitr~~e.tbWlill0f"F'ao~~,@~." '.'. .',,'
<br />HotcIDPss. , :Local industries rn:cluGletltider1Jioltng;c~'fd1milaing,~averft'F1\Jjri'gioo.d1b;g,ging. 'A!Htle..i:t~!Je@f
<br />An.tItracite'Cl'eekandWUddY'Creek.'w;tNe.Gtll1tIi~0U!Nati~lJ.al!pj)test;<lf'ele~atijj)~!~~i1l:~feet,.tilU.l?1;I~~i;~\!~~s.
<br />miles..in a$l\lllthiWestel1l dij:ectlonflll'&1:l~'a."'~,J.1e~.;.<ilfld'Wltlple~er'tejjtfaU~S;iJ!lWsJlt1~t:tedrifa'rej1i1!11~ai~14~ijl'i$lli~y
<br />di~sectCd''Ptoad yalley Wiflr,gl!fttle'ddWfi""alJeY$lbl'eoefOire~\iYi1\\r~~~'gWilli,theftJ;ain.~te1i16{clherG~s~1l. '
<br />River noJi1;h of the Gunnison Gorge and the BfaefuClUtY0:uot'tl1'e~1.ulmS~n~litit9tll\i1~a(i~. , ".,' ,', .,',.,
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<br />Degradatt@n.ofU\;eNorth Fork ofthe@Unhison:'RiYerisl\.res~lb0:fltist0Fica:gricultt!1!a:1ipra:cticbS',d1rl:~1~a1;i~n
<br />for flo:oelcprotcctlOn;, gravel t)xtractlon" ;mdgrazing. .In l'g.g2llieIl.Cfi!f1iforko'f'flreiG'ltnill'sdttR'iivetJ"al~Y\\1a}l
<br />of.ficially opened to settlement hy the U.S. go"e.rntnefitf6nowiF1~.tlll;).Jielo'catton ofthI;lEJiteln:d1-atrs. '~~lllj;j;g
<br />to an lS82manus;criptofEzra Wade, On:eOfthl;l'~rsthomcstea€fers\th~riiveFW!lS very ~'ero~k<l\lif'atidskWelf~;ol1t
<br />across. a IllFgeandthidcly vegetatedf100dp1ain. Tlht) vaUeywasim.nued'i'atel\yrecognirz"€cl. f()l; i'tS'~(,j1l\l~a1 '
<br />p@tentlalatrds@on farms and OF\5hllFdSiSP1ilng.up.afongtherh'erre]llal:J.l:ugtlle.ritiwtan'vegetll,tion."..~Vei! ,.'
<br />meatrderswere taken out and the river was straightened to maxill:1izethe areathatc()ulcl.be putint(1)l>~u;l;tt!1!al
<br />.oduction. " " ", . ','.. .,' " ,
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<br />Straightening the river has caused problems. .Wittloufflreme;mq.ers, tbeU"et1i1owed.fastcr--eJi?di!rg:'\"J(!Hksrand
<br />flo@mflgun-vegetatecl..fields.', Thelbcalsbuilt cl.ibsAOfm~'te~ttht)fal1UllWfrfl~.tfferiveFattempteirlt(z1Ftec~.its
<br />flooirlp1ain.Prior to 1948, rivermodi.fications for flOod control werell,ccomplishedbyhand1ll,oot withihotses
<br />anddynamite. After 1948, bulldozing of the chani1.elbecl1U1ea1iani1.naleventuntil1980, when theC'lean, Water
<br />Act started to regulate in"channel activities. Channelizationofllie river cut the rivet off:fi:omits fl@6dphtin,
<br />which increased stress and erosion on the riverbaftks,decreased wetlahdafidriparian areas, devas;t'lltOOffsh
<br />haoitat, and ~educed water qualityoy increasing sediment yie1(!to,llie stream, A.d1fiuonally, graziug'praetices in
<br />certain locations have destabilizedoank:s and precipitatt)dsevt)rehaftketosicm.
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<br />In-stream gravelexwaction at three separate locations has severely inWactedthestream channel and~ottid't:lr.'
<br />Gravelex:traction sites haveintrodu:cedpoints of abrupt'chang~ in the lon.gitudinalptofile'ofthe &ttelWtQa:n'ed
<br />knick"points into ,the channel. Knick-points initiaUyinduce streanlbedi:uCision and degmdation and4plt!mat'ely
<br />lead to sedimentation and aggradation asthe knick.points ttllgrafeupstrearn. ' ,
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<br />Water rights are over-allocated, leaving some stretches of the river with no base flow. ,General1y,agui,cnlma1
<br />diversions take out more flow thanneeuedand refurn the wate~ downstrearn. Mostofthesediv:ersiiJhsafenot
<br />screened, thus, agricultural diversi@ns and run-off from surface water irrigation hav:eGlercreasedwaterq:ua:lify.
<br />The Colorado Department ofPubIicHealth and the Enviromnenfidentifte'dthe N0rth Fork wafersh'eirl>a'sa
<br />priority watershed in its 1998 Unified Watershed Assessment.
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<br />aiththe loss of much of its function, the rivercontirlUes to degrade as eviden,ced oyhighbaftk etoston"near1y
<br />'n-existent riparian buffers, increased braiding oHhestrelWt channel, ,decrt)ased water quality, hicgh~er'<l.ti@n
<br />and maintenance of bridge and irrigation structures, and severely reducedfisnanGlwMllfe habitat. '
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<br />L,ISection FolderslSECAIBoard MeetingslSeplember 2002\Agenda item 1 9-Corps report attachement.doc 09/03/2002 PM
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