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<br />Fo",,,,,,,,1
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<br />Study Procedures
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<br />Cross SH_tlon~ Were surveyed th.Qughout the flood plain using sea level
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<br />Bo""lde~ Creek dr..inagc Hcs north and east of Ft. Coll1tls. The "pre[
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<br />datum. B"lldt"g~ kt"'''e~ ~~r}ss ~e,'tLon" were tnsr<,cted "nd their elentto'l
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<br />draInage odgtnat"s in Sout!oe,n Wyoming ,,'w flo>l~ sm,tn to th.e ,:onfluence
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<br />determined if th.oy apf><'"re<! ~Q be "ah. the flood line.
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<br />>11th the (;lI.d'" 1<1 Poudr.. Rivef j,,~t 80\lCneast of Ft. CQllin~. The flut
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<br />The SCS ~a~er Surface Profile Prog(~m, W.S.P.-2 was used to rate all
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<br />(cco~natssance of th~ ~atershed ~a~ In the I~te 50'. and early 60's.
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<br />~[OSS
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<br />seU1ons., \Hth thls info."",~jo"l, ,,0 ei"ntLo[l of the brc,'ch flo,",
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<br />Damaging floods have occurred over the w"-terahed in some ~_<t almost
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<br />"o~l": be c~~<>~~~"i",..: At ea~\: ~rO"s see~ion. These '"'ater sudace ehva~ions
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<br />e"ery year. Watershed ~tlldiea sho,", (I rather wide flood plain throughout ita
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<br />were es~ablished for all crosS q~c"ions.
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<br />entire length.
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<br />This i,-,f'lrmatton was ...~ed ~o d"-,,elop an accurate flood plain 11M.
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<br />Boxel<.ler Creek waS appro"ed for planning and flve floodwater re~ardlng
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<br />structures and one grade stabilIzing structure were approved for construc-
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<br />tion. All structures are complete except strucl~:D B-2 which Is under
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<br />Areas Flooded and Depth of floodIng
<br />This report Is li~ited to a ::~d) ~f the flood ~13in ~l~w thp
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<br />constru<,Uon.
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<br />The Boxelder Creek Watershed Work Plan was dev~lo~~ ~J
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<br />sl:"ctureB-2"fthe8oxelderCreekWatershedWorkPlan, that would be
<br />inundat~' by an Instan~aneous b"'ea<,h of the structure. This report cleUn-
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<br />Gol11n~ SolI Gon~ervatton Distrt<'t, West Greeley Soil Gonservatton District,
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<br />Lart"",r County ijoard of COl1IllIissioners. ColorsdoState SoU Conservation
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<br />eatesth"potent1al"-rMoffloodt,,&shouldthisbre,,ehoc<our.
<br />shOWS these ar",,-s in the flood plain tha~ ",Ul eltc.,ed a depth of flooding of
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<br />It also
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<br />8o.:irJ, frontl.H SoU and ',Jater C""""rvatlon Di~trict, Lara",ie River~ SoU
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<br />and Water Con~ervatlon District wi~h assistance from th., 5011 Conservation
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<br />three feet.
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<br />Service under the authority of Public L"w 566, re"is"d. The purpose of the
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<br />Just below cross .action 007, "long the north edge of Wellington, the
<br />flow divides. (See ~i!lures 5" 6) At cross section 00611, the flo", Is
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<br />I'roJe<Ot "'''s to provtde f1o"dwa~er protection to the valuable irrigated ta.....
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<br />lands lnthe BoxelderCreek flondplaln,,-nd to the Town of \o/ell1ngton,
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<br />divid"d into threes"g",el\ts. Segment I Is the area "ast of the "",in channel
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<br />Dur!Oj! th" w~ter~hed ~tudy, It was determIned th,,-t both B-2 and B-~
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<br />th~t o"erHo"'" the railroad and enters thE> north part of >lell1ngton. 5"g-
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<br />structl!res "'ere mode rnte hazard. La~"r inv"sUllations in 1979 al1d 1980
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<br />m"nt 2 i~ th" <Min ~hal"",I alone. Segmel1t) is ~h"t portion that overflows
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<br />supported the earlier mod"rntc h~~~rd classificAtion.
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<br />to the "'est. This croSs se~t1on estabUghed the amount of fl"", [1".t 1s
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<br />By req"es~ from the Laricoer County COr.lmiss ioners. It "'''-s .~grecd that a
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<br />divided into the e,,-st, west and channel segr.lcnts.
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<br />breAch hydrogr..ph ",auld be rou~ed through th" nootl pLdn in~l\ldir'<l the To"'n
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<br />The madm"", peak flo'", M the d"-llIis 111,814 efs. This Ho'" "'''S reduced
<br />by tlU! routing procedure ~o 51,122 ~f, nt ~ross ~~~tion 0068 on the north
<br />edge of W~11ington. The flo'" on both ~ast aLld ....cst stdes of Wet lIng ton doe~
<br />not combine as ono no", until it teaches the "outh edge of '.ellington.
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<br />of ',Jellt"gto,\. ~esults of this rOtltt"t ,",oold he dlsrlayed on "ertal )'l1oto-
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<br />,:raphs to,ho"'tl,<' e>(tent of flooJing an<.l also th""r","ls th.ltl.., vEadepth
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<br />of f!o"dinggr",,-terthnn1.0ft.
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