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<br />"r",~, ~J"~ beo.1 select~ t.e~ Tnls STudv.
<br />
<br />uti I i led for g ra ling, with th e I ntllr5pllr5 I ng of some ~lay I ~ nds . On
<br />t~e main stem upstraa~ of tMo Seuth Fork confluonce, residential
<br />Co',olopm()nT has fully utillwd the flood plain. Along South Fork
<br />from Enst IJ4th AV<lnue to tlHl up<;tredm study limits, foursrndll
<br />detention da~ and reservoirs located On the stroam are oncouraglng
<br />the urt)ilnl zatlon of tni 3 Jro.j. Immod I~~o 1'/ upstreilm of the study
<br />raac~ on the South Fork, Hignlanu Memory Gardens Cemetery straddles
<br />tMestream,andagolfcourse;sstill furtherupstr"am. TMespreild
<br />of urb~nlzation Is expected to contT~~e dOw~strBam with tMe eastward
<br />>lXpolnS iOIl "r I",rthg I",ron dn~ Thornton. v~ Iley widths j ~crease pro-
<br />gressively in the dOwnstre~m direction, ter~inating Tn a broad flood
<br />pia i n near the mouth. As a rosu It of th I 5 va Iley topography, fre~
<br />Guent floodi"9 of tho valley floor may 'eexpoctod. Those factors
<br />would Increase tho potontlal for flood damages os development con-
<br />tlnues downstroam toward the mouth. The strea'" profllos and cross
<br />soctlonspresent"d in this rOI'ortshould be useful guides and ref or-
<br />anCeS for planning future develop~ants and pointing out Mazordous
<br />tlooclonas.
<br />
<br />FlooeC"ntrol imDrOVeme"ts
<br />Since the stud,! dre~ Is pre,ertly ""Jew)loood, nc majoe
<br />t I.-md con trel ~rojcc'fs hilve beo" c"":5tr"ct(Y'~. Loc:a I W3~"r ST'lra'-J('
<br />ro:;e,yol r~ huvo been COll~tn,ct"d in thO up~or 0,15 i n as G r05U It of
<br />~r~a" 'J,"owtc.. T"e~o reservo T rs Genera I I,. do not I r.c I.Jde spoci i Ie
<br />flooJ cc>n....ol storil00, "nn t08 only coolrDI exerc.sed Is nr(l"gr
<br />d i sch~rge Ilml tatlon of thc out lets. There are no ::;Orps a' Eng I neOrS
<br />I iOlJ~ cOr1ITul prDj<'Jcb i" Ihe L>d~ln.
<br />
<br />Stud,! Reach
<br />
<br />The study reae:h beg;;s at t~0 Sv"th Platte <1Tv,)r a"d
<br />foll"ws Grelng.. Hall Craoi( unS'frearn to tne junction .~ith Soub Fork,
<br />ooout 4 miles, and"" the South Fork fro," its corfluonC:8 witM the
<br />ma I n shIm upstrellm to IJortM ',iash i ",)ton f!o~ I ev~ r:J, abo,"t. I. 3 I~ I 100;.
<br />No t lood OIJtl i nos ","<'J ~nown "" plilte jli for the Gnlrl<)o 1,,,11 Gr'Jck
<br />roach frO!, j'he '"",,-,ut~l 10 R i vord a I e I ~Oi] d . TMc CO[.1b i ~3 t i on "f ~ "'Ge r
<br />sloP'ls. ~h]llow flco:J :J"pt~]S, ilnC li'"llted c'lan',,,I capacity b~ -'11,
<br />rOi~ch co("b.n~ to ,....1""'"' rl'e Ilr",~ e.,tli"e in'.1'l.,.'~r'l\ini'lt" '"i~~:)ljt a~dl'!"I"r1~1
<br />
<br />i rr i 9,] t i 0', . L P 5 trl'd"] 'rOl" 1 ~ i V" r<: d I" '(De U t:J I rrna r)r i vc On t:'.e ,""; n
<br />"to'" "rt: ("r,t In4~r, 'Won.]', ''', "oul,' 'or". t~" I arJs ,1re I<>r"e I y
<br />
<br />8ridges Across the Stroum
<br />Two higMway bridges cross tho naln stom of Grange I~I I
<br />ere"k Inri", stuJy re<l<:h. I n add I tlon, Ihe Union P~e:i f Ie: Ra II r"'~G
<br />cresses ~hc ~troom on J high cmL>Jnkmcnt with " ~ultl-pl~te oTpo to
<br />convey stream f low~. N" cata are ava Ilab Ie on t.~o E~st I04th Aven""
<br />cross;n~ 0/ South Fori(. Tavio 9 displays partinent elevations for
<br />th~50 str"~tu~os aod shows thoir relationship to t~c l"termc~late
<br />iloglo"a I F lcod. The ~ lans Jnc prof I I"s, plates 3;") tllrougM 32
<br />indicate t~P. flood potontial at tnp. bri~gos dnd their ostimated
<br />etfects on be pass()ge of tMe Interr'1edlilto fleglo"al d"d Standard
<br />Preject Floods. Cros~ s<Jctl"ns on plilt<'J 17 show the eeptn ~no "iCTh
<br />of the Intormeo;a1o Itogional anu StJndard Project Floocs.
<br />Tno Union Pacllic flaiiroad <'Jrnban~ment e:rossin~ tho str~JM
<br />abollt a third "I d IT'll e do~nstrearn /rQF, tM" Sout', ~ork junc~ion ""S
<br />
<br />cx~()n~ Ive topoq~3pn ie ,crveys. '!O",O'ior. to prov ide '0" IJanec in toe
<br />pr"",,,r ,'~" <>j I'i.,~. flOOd JI"in, t!l(~ ~xl"n~ 01 f !'",u I '''I '""" cstl"HI"d
<br /><led J '.-.'"tcr sl;rf,lce prof TI" c"vo lo.~od f,,~ t~" I o'"or roach. Th I '.
<br />~r()tll~ Is includ,'ld on pl.1t" :lJ, t",t In 8ot,,~1 'Iood '""y ,;Iftur fr(")(l'
<br />~Mat shown.
<br />
<br />Oev<,loo,"",rts In the Flood Plain
<br />1I.'l1ar i z"t i on In tl,r 5 tu~,y rt'.,ch i e, ')"e"r~ i r.~, I n T~"
<br />"xlr""" urstr"m- portio," '~it~ t'I" riJ""indor ~~III r"rdl h cl1d"dct,-",r.
<br />"r-u(', I.!,,,, j u"~ II "n lJ I '~r.""'J8 : Id I I =r-8"~ 'jllJ II,,, S()~ th r I" t:", "i V.cr- to
<br />I{ i y()rJa '" '~"ad. tM" flood n la i r1 I ~ cr,,~ I anC '.' i tll n I arc]" ~ort I On U1U'''-
<br />
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