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<br />Hy<iraullcs
<br />
<br />Su",,,,,rv vf Pea;' n""," in cfs fvr llmwlder Creel:.
<br />
<br />Ch~nnel
<br />Location
<br />
<br />The U. S. Army Ettll;ineers HEC-2 c(}mputer pr,,~ram waS used ~o perform
<br />
<br />'{ear
<br />X-Sec.
<br />
<br />DraLnage
<br />Area
<br />(sQmi)
<br />
<br />Recurrence Internal In 'fears
<br />
<br />'later surface profile computations.
<br />
<br />Numerous bridges and culverts e~iBt
<br />
<br />,
<br />
<br />w
<br />
<br />"
<br />
<br />;0
<br />
<br />W"
<br />
<br />;00
<br />
<br />alon~ the chamnels th,,,~h the study reach. Those that created sill;nificant
<br />
<br />1J/~ of ',Iindgllr
<br />OUch
<br />
<br />KJ
<br />
<br />10.R4
<br />
<br />I~O
<br />
<br />470
<br />
<br />,m
<br />
<br />R"n
<br />
<br />10R()
<br />
<br />lS1()
<br />
<br />backw~tef affect were handled in the HEC-2 analysis with appropriate brid~e
<br />
<br />u/s of C<llorado &
<br />S<luthern Railroad
<br />
<br />'"
<br />
<br />12.68
<br />
<br />.60
<br />
<br />,eo
<br />
<br />'9"
<br />
<br />eo"
<br />
<br />1140
<br />
<br />1&40
<br />
<br />routine., A fe'" bridges ,,,.d culverts are only minor sei>:llIenu of the tut>ll
<br />
<br />flood plain and therefore ",ere conaidet~d in the Mannin~s retardance fact<l,
<br />
<br />u/s of 1-2S IWar
<br />Wellington
<br />
<br />"
<br />
<br />13.M
<br />
<br />""
<br />
<br />4HO 710 no
<br />
<br />1170
<br />
<br />1~90
<br />
<br />tath~, than In separate bridge analyses.
<br />
<br />D/~ of r-25 "ear
<br />Wellington
<br />
<br />"'
<br />
<br />24 .4~
<br />
<br />,eo
<br />
<br />9()O 1270 1670
<br />
<br />2140
<br />
<br />1100
<br />
<br />Cross section data, and reach length information ",ere obtained ftom
<br />
<br />photogrammetric IlIapS prepared especially for this atudy. Hydraulic
<br />
<br />U/S of Wi.1lox Roan
<br />
<br />,
<br />
<br />55.94
<br />
<br />5lD 1140 1860 2730
<br />
<br />3770
<br />
<br />5820
<br />
<br />rO"Khne.. coefflC1..nts (Un" values) '<<'te determined from Held inspection.
<br />
<br />Indian Creek
<br />
<br />M
<br />
<br />20.35
<br />
<br />"'0
<br />
<br />"'''
<br />
<br />8501350
<br />
<br />1930
<br />
<br />3100
<br />
<br />1inddocumentedwtthphotol(tl\phs(lnteehnicaladdendurn). Foilowinll' are a
<br />
<br />Coal Creek!1
<br />
<br />"
<br />
<br />10.60
<br />
<br />70
<br />
<br />'70
<br />
<br />",,,
<br />
<br />,00
<br />
<br />""
<br />
<br />1300
<br />
<br />tabulation of these roughness coefficients for various locations along the
<br />
<br />!I A hydrilul1c study of Wlndsot Caoal Ind1cated it would intetcept nO","
<br />from Coal Creek up to 200 cfs. Therefore. these di.eharges have been
<br />reduced by 200 ds. from "alues shown in the SImons, L1 to Associates,
<br />Ine.report.
<br />
<br />.tudyarea.
<br />
<br />Wetet surfaee profiles, typical cross sections and maps showing the 100
<br />
<br />year and 500 year flood lines are shuwn on exhlbit" A, B. and Flond Hazard
<br />
<br />The IJ.ox~lder Creek Watershed Pro.1",,-r flo<ld",.1ter r"t.,rdIng structures
<br />
<br />Arell'1aps. Table 1 sho",scomputed fl""del<,vatlonsatapecificcross
<br />
<br />reduc,,-d the lOG ye,H p"dk no", ..e ~he j'lnc,lu" uf Ruxel,l",- Cre,,-k ,mJ Co..l
<br />
<br />"~c.t1ons.
<br />
<br />f,re..:': frorn 13,3f)~ cr., to 1,170 cfs. At the !<,,,er end of the ~tLjJy. the lOO
<br />
<br />Hydcnulic Roughness Coefficients (n-value)
<br />
<br />ye~r oeak f1"" ",as rednced fn>1lI II,Qon ds. to 1,llO cfs, Peak flo", nil Coal
<br />
<br />1~
<br />
<br />Section l.eft Rii>:ht
<br />Fto'" '" Overbank OVerbank Channel
<br />, M .040 .050 .035
<br />'" " .050 .050 .040
<br />" " .050 .045 .040
<br />" "' .045 .050 ,040
<br />" 'J .040 .OSO .035
<br />" rn .045 .()45 .OM)
<br />" " .050 ,0;0 .050
<br />GH "" .O'jO .OlO .050
<br />'" "C .050 .050 .050
<br />He "" .05rl .070 .050
<br />~ '" .050 .070 .060
<br />'" "' .()~II .1\70 .rHO
<br />'" '" .050 .070 .05',
<br />" ~ ,05n ,(140 .ctl.O
<br />"" " .M5 .'.145 .(14';
<br />
<br />Cr,,~k, thou,o:h the To",n of Wellln>>:ton, ...re reduced ftom 3,41,.) ",_is. to ~3ct
<br />
<br />cfs.
<br />
<br />Note, Tlocumenting ph"to~raphics can be fo"nd in the technical "upplernent.
<br />
<br />'"
<br />
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