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<br />dow","eJm(()uld 'oll<"t 0" bmjg<"or olh"r
<br />ohwuni",,>. lhu, "<'atiog a damming dfeet
<br />and overbank flow, A> Iloodflow in""a,,',.
<br />maS,e> 01 debri\ can de,lroy a br;dge or cau'e
<br />watef leH~lto ,;,e high.., and mor~ fapidly thM'
<br />normaL thu> erooing and damagingahutmem"
<br />approacht"...nd the overlying roadbeds,
<br />In W'rw,al, ob<;1rLJrlOOm restrin floodflow,
<br />"nd may (aU,,' overb.nk Ilow;, unpredictable
<br />ar...' of flooding. possible dam"ge to Or
<br />de,nuclionofbridge\Jndolher'treamcrm,-
<br />ing"andincre"edyelocityoiflowimmedi"lely
<br />
<br />dowmlr<'Mn,Eighl"",dbfidge"iourdin.",on
<br />'tructllte',andone drop mucture are obmuc-
<br />tive to floudllow', Pertin~nl oata on lhe,e
<br />'lmcWre, are ,hown in Table 3. The efl~u of
<br />ObWuclion>mayhe'eenonPlate,58.59.61,63,
<br />66, /2, 7), Jnd 7;;, Water surface elevation>
<br />,hown on the pldte' and in Tahl.. 3are ba;edon
<br />the ."umpljon, th;)1 b,id~e openio~' remain
<br />unohstrucledbylfoodborn..-debri,ord<'po,ih
<br />ol,"nd..'d,ill,Jndthatallgate,ondive"ion
<br />'trunurl',areclo;t.d
<br />
<br />VELOCITIES OF FLOW
<br />
<br />During a loo.Year flood, velocit,' oillo...",
<br />the channel of Ihe Uncompahgre River woulel
<br />dver"g~ 6-9 ice' Ift" ,euJIld tirrou~hout the
<br />>IudI' reach. \"elocilY of Ilow in ov~rbank dre",
<br />wI",leI l>~ ~bour 1 fool p~' "",:or,d, In ,h~et
<br />flOW' .,ea>, .v"ra~e Ilow v"lo(it)' would rang~
<br />trom 1-3 ie~l p~r "",ond During a 5l11J-ypor
<br />lIood,velodty 01 flow would be ,t;ghtlyh;gher
<br />th""during alOO-yeorflood,in,omekJ(;)liled
<br />wNrnreachc,.lore<amplearounJbend,or
<br />immediately downstream fro,n ob,trucbon\ to
<br />flow. velocjty could 'ignifi(Jntl,' exc..ed tho,..
<br />
<br />FLOODED AREAS
<br />
<br /> TAIlLE 3
<br /> OBSTRUCTIONS TO FLOODflQW
<br /> E......lion'
<br /> UndO',- Top of lOO-V....' 5tlO-V~~r
<br />Idenbliulion l<x..iun' Slreambed ck>arance' Rwd....!' fluod ""'"
<br />Stall' Highway 34e 81.58 5327.7 5337.0 5340,Q 5336,8 5337.4
<br />Church ^vcnu~ 83.Hl 53365 5J48,l} 5151.0 5.147.7 5347.9
<br />Ea'l C3nai O;v.."ion ".00 5373.4 5376.9' 5382,5 53ll2.8
<br />Iron,tonpCanal Diversion 100,% 5434.0 5440.7' 5445.7 5446,(,
<br />lay Jay Road n5.5J 5517.2 5529,0 55J3.0 55251 5526,8
<br />DropSt'LKlure 137,35 %59.5 . 5670.6' 5678,5 56789
<br />la Salle Road 137.40 5669,0 5678.0 5&1.11.0 56796 ""'"
<br />U,S, HighwdY 'j5{) (S",,'hl 174,35 58934 5'!OIJ,0 5911,0 ,g9':l.8 5'1llO.7
<br />U.S. Hlghw~y ,50 iSurthi 17443 Stl93,4 59Ce.C ,912,0 ,901.7 5,!()2.8
<br />Loul,enhi,e, C.nill Di,..."ion 175.90 51198,0 5902,0" 5906.1 ,'J()7.0
<br />Raci"<' ROild 184.41 5946,6 5957.0 5960.0 5957.2 ,957.8
<br />Montro"".nd Dcll~ Canal
<br />Div""iur\ 203.78 6075.0 b009.()' 61J'!7,b llu<Jtl,3
<br />TroutRwd 104,iO 601\7.5 WNO 5101.0 6097.7 &098.7
<br />
<br />PI.te 1 i, anjnde< lode,,,iled m.p,*,owin~
<br />lhe are.Stllal woufd be inund,ued by the 100-
<br />andSOO-yearflood,(Platc,2-SS),A"hownon
<br />lhme plale', loo-year flooding occurs along
<br />almosl all of the \ludy 'e;)~h. How"..er, over-
<br />flow woufd remain mO\lly in narrow 'hljacenl
<br />b.1nd,. ..xcept in Mea, mbject 10 ,heel flow.
<br />Floodwoter would cover low-lying are,'" lhal
<br />include agricultural land, a"d improv"ment\,
<br />rural re,idence,. and ,ections of county foad,.
<br />Railro.d property would be Ilooded on th..
<br />we,t ,id.. of the rivcr aboull to 2miles,oulh of
<br />M<)ntro'~and in 'everal Jteas Irom 1 t03mile,
<br />soulh olOi"rhe or1lht",.,,1 ,ide oi Ihe';ver,
<br />Oyer 1/2 mile of State Highway 348 an llle
<br />wc>t~rn ed~e 01 Ol~the would al,o be floucled.
<br />The anly urban areJ, <ubjeCl to floadin~ Me in
<br />the ,0ulhwe'l corner of Monlrm~ and ,Ion~
<br />lh~ w..stern edl(>' 01 Olathe, Some Jr.'J' would
<br />
<br />FLOOD DArwlAGES
<br />
<br />Al00-orSOO-yearflaodJlanglhe,wdy
<br />reach of the Uncompahgre River would cou,,,
<br />,uh"amialagricuf!uraIJndpublirf.rilrtydam-
<br />,'g,.. R~,idenli.1 "nd<:or""'~rrial d"m"g~ wo"ld
<br />be I~" <;~,,;fica"l i"'<:a",,, the urbon a'ea
<br />,ubject lo inundalion ;, ,m.11. Agri,ullu,al
<br />10'"'' would ~o",'SI of de>tructlun 01 orop,;
<br />uru,;oolulj.>."u'u4ndcrupl.,,,.h; d~po,il;unu{
<br /><ill,sand,annd"bri'O"""p.,ndp."u,,,land,;
<br />,1nd darnal(e r" I"rrn.,quipm~nt.building,.and
<br />irrigM10n 'y'lern" Re,idential I""", would
<br />;n,lude d.mol(e to ioundalion,.low"r (100",
<br />w,lk I",,,i,hing' ;",<1 appli.,,,n.<, ,,,.1 "u,,;d~
<br />
<br />'A' ,he "p'''Nm f"", <>t rho ~ru<,u'e "".",,, im '"1' o' '0,0...."." ,"",,>0<>,1 C"'~"'''r \"""".,11"<"",, '"2' "i""',~,,"r,
<br />'n,ou""'''' "f f....' up>;"',,,~ f,om ,""u,11 of .i"~r
<br />'I..-.w ,'....1" ",w"" "",nt "" ~'u,'''Ir''
<br />_^, ,~c <,<"'c,I;." oi .o><lw", ;"-,med,,,,'I,' .0<,," ""00"".'",,'''''0 '''''0'
<br />"'<>' ",,"IK,~;e
<br />,^, t,~, "f l.lI
<br />
<br />'ll""d '~'''''''' """I,"" t1,,~ >1""""'" Ie>. I,"" , ie'~ deep
<br />
<br />"
<br />
<br />;ndicJled.bovc.
<br />,Vate,flowl"gal.r.'eof7-efe"tper,econd
<br />0' 8",atef will ca",e ,,,v,'r.. e"",on 01 'tr~'m_
<br />hJnk;andi,qpahl"<1I"dn'por"n8i,"g~"'ch,
<br />~[[eamb"nk, and the fill "round blid"e ahut_
<br />mpnt' may h~ e,od~d .lnd Idfg.. .mOU"1> 01
<br />g'rlY"1. ",,,d, ..nd .;It '''ill' be tr.."po,,~d by
<br />WdtO', Iluwr"~ Jt . r.". "I 5.7 I"el I'~r ,,,,ond
<br />"','"\t'r flowing ~t aboul 21~el ~~r ,,",-ond 0' Ie;,
<br />will dep"';t ,and, ,ilt. and other flood-borne
<br />debri,
<br />
<br />be' ,ubjetl w Sh""l flow. whid1, a, ""t~d earlier,
<br />i, brodd, ,haUow overland floodinll g""eraily
<br />I~" than 2 f.,et deep. 5heCl flow flooding i,
<br />ch",ilcreriled by unpredictable Ilow path,. It'
<br />waler ,urfac.. "Ie.~tion would be e"entjJlly
<br />i"dependent of the watef ,udace eley"tion of
<br />flow along tbe adjac~nt 'treamway and i,
<br />aHecll.d ptincipally by flalural Jnd manmade
<br />baniers to lIow in the floo<k'd ar~a'. Shallow
<br />flooding (generally lesslhan6inche,d~"p) mal'
<br />ocwr beyond the flooded Me""hown on the
<br />map'. Thcde~rh of flow in the chJnndof lhe
<br />UnrornpJhgre Riv~r ,"d adjace1lllloaded orN'
<br />can i,,, dete,min~d frorn Ih~ Ilood pro!ile'
<br />,hown on Plate' 56-7'<, In lOlal. the 100-y"a'
<br />fiood would jnundate appro<imately 1,720
<br />ac"", of wh,ch 1.4)5 acrel Jre J~ricultur.l. 210
<br />"cr~, are mearn chan"..I, and 5, due> <ore
<br />uroon.Asn'JII.,creJ!(eolro,d;lndrailroJd
<br />"ght,-o(-way woulrlal", be inunel.l"d
<br />
<br />improvement'. Commercial Im,e" would be
<br />minor,bul c()uld involve >tructurJI Jnd equip.
<br />menl damd~e, 10" of inwn1<>'\" and tempor.,y
<br />10<' "I bu,ine", Public f.,dlitv Io<,es would
<br />1.11gely compri.e dJrn_Kt' to rO.1d, .nd road
<br />bridg"', Railroad ,'mbanKlIl<'m" He,tle,. and
<br />brldg," wO<lld al", t... ,,,bl,'ct 10 dama~" or
<br />d..,"u<:lron, Olh~f flo",J 10''<'' would [,~ ,hit
<br />comofiloodfighlingandpo-.tlluodcfeanup
<br />and repa;,. Damage would be gr"ater during a
<br />500'ye"r flO<Jd th"" durin~ " 1oo-y...r floocI
<br />becau",flo<>dwdlt'rwouldb"wide'andd""p~r
<br />.,,-,d flowing Jt .i hi~ht" .do, ill'
<br />
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