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<br /> TABLE 4
<br /> OBSTRUCTIVE STREAM CROSSINGS'
<br /> Et...uO<l'
<br /> Un<l<.- Topol lOO.ye., 500-y."
<br />l<fonllllc.llon l<le.Uon' Slte.mho.; elu,.noe' I\o..;w.y' Flood Flood
<br /> COLORAOOI\IVER
<br />CronJ Av~nuo (~"'l<
<br />Hj~hwa~ 3.\0),
<br />W..IWL<ndl..:mos :lil5..';:1 4'>:18 4559 ,1562 4,%3 4;;[,,-;
<br />EOSIwundLao"" :1ll5,5G 4538 ,1559 4562 ~bf,~ ~:;S6
<br />ORGWRR .'!&i.7I 45,tf> 'If,ll6 4510 4f,1;3 ~f,ll:,
<br />"tb St"'rt(t:,S, f,o):
<br />Nurt"boun<lt...nt'. :18G.8:1 4;;~~ ~i;7U 4;;75 4J(~ 4O&i
<br />Southbouodl"""" a~;.~4 4JOU 4r.65 4572 '''' ~"67
<br />32 Road 39.1.05 _1606 ~62fi 4f,1O 46~1 4629
<br /> LEACHCREH
<br />R;vorRoad. 2,040 4fi32 45~0 4.\-ol~ ~J43 4r>4.',
<br />ORGWRR t,lIIO 45:14 ~541 4:>1,> 4;'~~ ~J46
<br />U.S. Higilway6i5U. 2,410 4536 ~5~2 '"' 4545 'M'
<br />6/50Fronla>t<JRMd' 2,1;25 ~536 iSH ~S4S 4.->'iS 4547
<br />24\>Road' 9,890 '''' 4S74 4S75 4574 4574
<br />25 Road' 12,530 4m6 41>87 ~S9! 4J90 4!;W
<br />M.inLinoGrand
<br />V.lI.yean.1 t3,6.1O 4584 4594 4599 4593 ,1.;94
<br />G\-l!Wad. 19,130 4627 "" ,,~ 46~0 ~640
<br />!-70f'ronlal!<' RoaJ' 19,540 4638 46~~ 41i61 '"00 4661
<br />26Ruad. 2l.:l30 '"~ 4659 4662 ~",,4 4667
<br />"""'. 22,570 4f,1;f> 467t ,~ 4685 '"%
<br /> ~EWISWASH
<br />""'.. 2,070 ~610 '"~ 4622 4621 462:;
<br />O"Ro<.<! ~,730 462'J 4633 'M' 4639 '16~2
<br />F,Road 7,:170 ~644 46,;'; ,~ 46,,7 166\
<br />Grac.dVane}-C3nal H,\2(l 46~t 4664 46ft! 1663 ~670
<br />r}.g. Hit""'~~ "iN 9,NW ~~~.~ ~1l74 ,1~lK .1MII 4M7
<br />fo:\'iRoad 1O,0.~0 4672 ~5g2 1685 '1fi8~ 4686
<br />F\iRoad 15.470 4737 H.~ 41:-.0 n,17 4752
<br />In:<."ota,.70' 17,&10 1762 H6~ H7~ 4770 4779
<br /> HORIZON ORIVE CHANNEL
<br />P,iv.teCco..ic.ll'" 9,200 4fiSO '''" ,,~ 4591 4.';91
<br />Pci..t<Cc",",iol!'" 9,7;0 4~8 4594 ,1>95 4t,% .If.96
<br />26 Road" 10.400 45~ 4604 '"~ ,,~ \~07
<br />26\iRo.d" 13.450 4,a8 4028 40;:14 4ti:l5 46:ltl
<br />~lain Lin< Grand
<br />Val:~y Car,a:' 14.~0 4G:W 1635 1:>1:1 1635 \~~.t
<br />GrandV.lIel'HLKh.
<br />lineCan31' lUOlI ,\64" 4649 4';;>8 ,16'i:' .11~iil
<br />HocioonDri". 16.540 4648 46.~3 -1057 ~';6(l -1661
<br />27 Road. 17.440 46.>7 ,~, toW 4670 4671
<br />C""'. \9.9LlO 46AA '"~ ,,~ 4703 ~7Q.l
<br />L C,I..",,,,, d";.",,,,1 1,,'
<br />, A< :h, "pM,..",," r"," of,h., ''''.L'''''' ''''''''< r,- lor <tl ,,,,,<I~.", "~""-<l:,, the ,~,,~. r.., "-"'''. "'" 'ml """"'
<br />'~,""."'t"'." t"m lA'" """", At",,,", ,", <h" ".1"""", ""","' r.~,"""",,",,,, ,,,.. ",0"""" ,..h,.", "",.".,
<br />'t""....,I"Io..."""""",,,,,,,,,,",,,,..'.I',,,,,",otb,;,,,,,,,,,,",,,"".T,,,,.,,,,,,,,",,,,,,,.!""'"",_""",,,<',,""
<br />,""."",
<br />'A, '0""'" ".. ,',","l i"tn~Ii,,," ....,., ,""'n~""",, ,."n',
<br />
<br />VELOCITIES OF FLOW
<br />
<br />!)urin.-;a IOIl-y"arf]md, avera,-;<','elo<.'iti.."
<br />of fiow in main cbanncl and overbank an""
<br />
<br />wnuld be as ,hmvn in Tahh' 5,
<br />
<br />TABLE 5
<br />
<br />AVERAGE VELOCITIES OF FLOW
<br />100-YEAR FLOOD
<br />
<br />Stream
<br />
<br />ColoradQlti,'er
<br />Gunni~u" River
<br />u,aeh Crefk
<br />UOri7.0lI Dri\'~ Cbannel
<br />Lcwi~ Wa~h
<br />
<br />'~""wd"ok f]"",",
<br />
<br />Velocity
<br />(feet per second}
<br />MaIn Channel Overbank Areas
<br />
<br />,." 2.4
<br />6-8 ,
<br />8-7 l.~
<br />:)-5 ,
<br />6
<br />
<br />In ~h~d flow' areas, ve[""it;!', would ran...t'
<br />from 1.;) fed per ,,,,-,ond, In ",'me loealizt'd
<br />;tr"am ",'aches, d{)wn~tre"m from natllrsl or
<br />m:'nmad~ obstructions, for ~xample,
<br />vd,,,-,iti,'" of flow C(luld silroiIicantly t'x",-,,->d
<br />th,,,,, <llOWn in Tabk [), Veloeity of flow
<br />durin>: a 5UO-year flood would be sl;~ht[.v
<br />lu"hcr th~n durin", a HlO-"e~r flood.
<br />Waterflowin~atarat.eof7f"etper"ee""cl
<br />
<br />FLOODED AREAS
<br />
<br />Th"ar~a.<lhatwotlld Iwinundal<-<J hyth.'
<br />WI)- and 5O!).y!'ar l100ds are shown on Plates
<br />2,57, As ma,' be ",,'€n from tho~c platc". the
<br />[I)I)-year flood on tbe Colorado and Gunnison
<br />It,,','rs would I><' wnf;noo w tbe Immediate[y
<br />adjac~"t overbank ar"as. Colorado River
<br />flood flows will inllndat!' bottom lands along
<br />thpnorthsidpofth,'rivPrandsandbari"land,<
<br />;m1n..cli~tdy Ilpstream from Grand Jun~tion,
<br />Tht, c,,,,,mt'reially d~,'eI"Pt'd nn'a near 1hc'
<br />
<br />1"0"<1, ",,:1,,'.,. 0'~d"r,d n,,~. ~,',~."tJy i"" ,h,," ~ !.-., d,",p
<br />
<br />,
<br />
<br />nr ~reater will cause severe eros;oll of
<br />strcambanks and ;, ~apahl~ of trao"p<>rtin"
<br />[arJl<'rocks.Strpambanb~nd tb,' r;lI"rmmd
<br />bridgf ab\ltments may he ~r<~l~d and large
<br />amount" "f ,o;ravel. sand. arid "ill may 1",
<br />tr~nsported by wat"r f1,)Win;,: at a rat~ "r ,>-7
<br />fert]l<'fs!'''Onn. W"I€rf]ow[,wal."h,,"\.2f..d
<br />llt'r "pcond or I~s" will d"]l<l"it sand. sLit. and
<br />other d~bris.
<br />
<br />Fifth Btr.."t briel"cs andlhe re,jd~ntial an,,\
<br />""ar Ri"""id" Park would be thr.,atenL'd by
<br />the high flows of the Colorado Hiv~r,
<br />t'loodflow, Can back inw the Conne"t;eut
<br />1....k"sareato1hesouthoftheriver,,,-" well...,
<br />into the lower reClCh nf Kn Thorollghfar<>
<br />Canyon. The high~r flows On thp Gunn;,nn
<br />Riv"r would flood a~riniltural :<rea"
<br />llpstrPRm from tbe mouth.
<br />
<br />10
<br />
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