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<br />VELOCITIES OF FLOW
<br />
<br />llurin!l:Rlfl(}-yearl1ood,aVNal'(e"elocityof
<br />flow in main channels and o'-erbank areas
<br />
<br />FLOODED AREAS
<br />
<br />would he as shown in Table;-,.
<br />
<br />Thl'approxirnal<' Ii mil<< ,,(illuod>ltiotl thRt
<br />would '",ult from a !;DO-year flood on the
<br />~tr',am' und"," ~tud}- ar,- "hown On Plat." 1.
<br />which ;'alw an index to more detailed map'
<br />,hm\'lnf(th.. "rea' that would be inu,,,bh:dLy
<br />th,- ll~l, antl500'l'~ar l1,-"-"ls (1'1""" 2-\;;). A,
<br />may Ii<' ",'en from those plates, th,- area
<br />inonda<<-dbythelllH-yearfloodalon!l:the
<br />Animas Hiverwould eseentially extend anOS'i
<br />tJw vall,'y fl(~))' throuJ<hout the ;tudy reach.
<br />FhJtl oHrflow along lIermu:sa Cn."k would
<br />dosely parallel the ,tream in the upper
<br />portivnof the,;tudy reach. b"t woulddiverl'(e
<br />int<' a wi<leni"l':fi>n sharl€ ea't<,r1y of the West
<br />An;mas Road cro;,ing-, The .~OO-year flood
<br />w,mld jl;pn"rally follow the ,;ame patkrn. a,
<br />the lOG-year flood, but. in -<orne location~.
<br />inundation would pxwnd farther [rom th~
<br />main str~am channels and bp ,uhstantiall)'
<br />d,-,'pt'r.i:ionwar,'a.<wouldb"wbjedto.h,...t
<br />now, which, '" noterl"&rlier.;~hr()ad."hallow
<br />(",,,rland n",'ding g,'nerally Ips" than 2 fpp!.
<br /><kcp,Sh,-ct flow fh><lin.: is charaderiz,-d by
<br />
<br />TABLE 5
<br />
<br />AVERAGE VELOCITIES OF FLOW
<br />lOO-YEAR FLOOO
<br />
<br />SlreamJApproximateReach
<br />A!\Il-lASRIVlm:
<br />Baken; Br;dl'(t'torh'cr mile,,{
<br />River mile :,l:l to momh of llerm'lSa Cr,,('k
<br />Mouth of Hermo~& Creek to
<br />lowe,' hmitof ,t\l<J.Y <1"':\
<br />
<br />IJEHMOS.'\ CJU:~;K:
<br />Upper limitof,wdy ar~a to
<br />s(ation:L-lllO
<br />Station 3.-100 W mouth o[ cr~d;'
<br />
<br />\'doc;'}' ,00",-",<<'<1 t>v ,\oim", f(jvorO'lorban" o"~.,
<br />
<br />Vel,,,-'.ity of flow durin..: " 1;111)-,-"", fl,~,d
<br />would l~' ,li!l:hth' hi!l:h,'r than durinI' " ]00.
<br />-""",.n",Kl.I",h"e\fJu"--c'a,,-a,,vP](>citi,.,
<br />\\'"uldr"n~0from \.:jfc..tl'cr"'cond,ln",,,,,,,
<br />h':1.1i7..,d "Ir""m ",';whe~_ for ,'xumpl" "",l<",d
<br />I)(>nd, or d"wn,l,wlol fr"m natllralor man"
<br />mad" "h~".",'t;o"", .....I",'jly nf no", wntlld
<br />"ill'jifi,.,mtly ~".",.rl !.hl' av<'r"~,,, ohuwn in
<br />T"ble r"
<br />
<br />11.",,,1,,,;,,.,,,.,.,,.,:;.,,,, ''''""'",...Ih;,,,tt,,,,, I,'. ,".'
<br />
<br />Velocity
<br />(feet)Jf'r,,-'comi)
<br />M.ln Channal O~arb.a"k Areas
<br />
<br />"
<br />,
<br />
<br />.,
<br />2
<br />
<br />5
<br />
<br />,
<br />
<br />\(l
<br />
<br />"
<br />
<br />,
<br />
<br />,
<br />
<br />FLOOD DAMAGES
<br />
<br />Wau-r flowinl-! ut " r"tcof 7 fed pc,'sl'cond
<br />or ~H""tprwillcuu""evl'r,'"r,-",io""f,tream-
<br />banb am\ i, ""pahle of transportinJl,"larll'e
<br />pwb. ~tr"amlmnb and th,'fill"",a,,,l bridl-:"
<br />"I".t"",,,t, m"y h~ .-rod,'.d, ami tar>!~ :lTnO\lnl,
<br />ofKmveL,,,ncl.aml,iltm,,yhetmnsportedh;
<br />W".t~r fln,,'i"!,: at ~ '"'.- "f ",7/c'f't r<'r ",<'on<l
<br />Wall'" nnwin" "t "bout 2 r(~'t I~"'",'e"n,lnr k,,,
<br />wil\c1"j"'"i\,,,,,,!,silt.~mlfloodbC)rnfdchr:,,
<br />
<br />,\ l'~I. nr :"~l-Y"'tl. n,"~'i ;n th~ ,tudy an,a
<br />",,,,,1,1 ","''''. .ul"(:<nliaT ;Wr;"lllt"..al and
<br />!.unlic i,wili(y dama,,~. RHi,j,'ntml. tnmnwr.
<br /><'ial. and ,,,.I11,tri;d damaj('- w"uld b,. Jp"
<br />Sili";fi('.,,nt duo' t" minim,,1 dev']"!"''''''l in
<br />fh"l prO!l~ aft'''" A,,;riculturallos",', w"uld
<br />""npl'i"" d~'tr"ction of crop" and liv(-sltK'k;
<br />dam"K" to [arm and ran~h impf<"','nwnts
<br />s!l"h '" i,'rijl;atior. ,)',wm" fem','" bui]di!ll:~.
<br />pri\'i\l" I(.v,".' and farm ,'""ds; :<nc1t,n(' eo,t,,~
<br />r'-'"'Inrirw (,l'lp and p",,\ur,' land erod,'d nr
<br />"(OVf'redw;th,illandd"Lri"It.,;i,l<'ntialh.;,,'~
<br />woul" intlud,' dar!laj(~ Il' f~llnd"tions, e,t~-
<br />rior a'H] in!.'ri",' '~'"Il,. fle)o,.,', furnl.<hinli,,,nd
<br />
<br />j:{
<br />
<br />unpredi('!.abl(' flow path~, It~ water _"urface
<br />~I~vation would 0.' e!',..ntiall)' imlplw'ml<>nt of
<br />thr water ,urfaee ei~vati"n nr flow alonyth~
<br />wljaeent .tr('amw",- aod i, aff,>eU'd princi-
<br />pally u." m_tllral and manmade harrien to
<br />[low inthl'ana" flooded_ The depth of flow in
<br />th,' ch"nnd. of the Anim~' Ri\','r a"d H..r-
<br />mo""-Cr"ckandadjaeentn,,,,(h>dar~:u;canlw
<br />deU'nnin,'d from the water garfacf profil",
<br />sho,,--non I'lat,'1< H;-32,
<br />In total. the WO-}'earfl()(wlwo"ld;nundate
<br />approximately 4,(~)() a('ft". of which :l,(i{)1)
<br />a('reS are a,,;ricultur...l, 3.~O acfC' arc stn'am
<br />ehmlnel. and ~O aere" are ro"d &nd railroad
<br />r;;rhL,."f-way.lt,houldhenokdth"tallofthe
<br />fl""dedan'a"hownon Plate"~,15m,,-vnothc
<br />i"undakd at the same !.;me Le"a",e fhxl
<br />producin.:comlition8inthedraio"K,'baoinsof
<br />thp Anima, R;ver and Horm""a Creek would
<br />not ""l'c"-'ar;ly '>ceur concun'ently. AI,o.
<br />"hallow flc",din>"(.:,,nerall.v l",,,than ~ ;o<'h,,"
<br />,h,,'plmal'oCCllrheynndthpfloodpda,.ell,o
<br />shown.
<br />
<br />applia"""',and()\lt>ldeimpNHtnenL,_"",,ha>>
<br />bwns '\1HJ ,..-a...1<-"" Publ;,. fa".il;t;' I""",
<br />"--o,,ld """'pri,e d,nr.a>"" 111 rnadf",d and
<br />,U','alll er"",ill>!', >L,lli Ii,..-, ,0',(,; of flc~)d
<br />[ij(htinj(, cleanup. "nd re~toration, Hailt'oad
<br />tra('k and emhankmentw"ul,l he,uLj,'ctt<,
<br />.-lama>,," frnm immd"tiQIl, and .tft'ambanh
<br />w",ulrlllf,"bj,'ctUlerosi"". A"",.",w.."riou,
<br />area>, could u,. cut off for l~-t'i(>d. n\l\!l:iol:
<br />frmn" few hotlr" W p"u!",hly ",ot rnnn' thao a
<br />f,,\\' d~y, <1"e to hwh W"roT rnnmwr"l:1.ll"",,,
<br />would indud,' structural and equipment
<br />d"maj~"_ tl'm!".>rary 10"' of f,tl;;,,,,ss, and 10"'
<br />,:if in\"\'"l<lry ,ulrcd em lower fl",rx,
<br />
<br />u
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