<br />The Flaod prollles !:la~ be u~,,<l in are", "her~ ccmtrover8" ilrts~s o,,~,
<br />
<br />th" 100-yea, fload oounda,y shoom em the Flood"d A.rea plilte". Sln~e the
<br />
<br />I
<br />I
<br />,
<br />I
<br />I
<br />
<br />pos.ible f1ood".a)' '"'Hh c"~r<'il<:hm"nt rl11<e' ,,~s "naty~ed 10 this stud)'. This
<br />
<br />,",,,s sil!lply " h)'d'''"lIc analysis in ,",hi~" the fla"d plain ""~ thearetf~"lly
<br />
<br />Flaod Pr"Hl" plates gi"e tlle ,""Upr gurfll.C.e "levation "-t " sreclfi~ point On
<br />
<br />~odlfied to cant~in floodin~ "ithin s"l~~ted e~cron~hment houndarI~A. The
<br />
<br />the ref"rence lin", th" hl1{h ",~t"r elevations can he surveyed on the >:rouod
<br />
<br />resultin~ ~ffects On flood ~Ievatia~s are shawn in an Appendix separate from
<br />
<br />to aUeViate <lOll' dh~<ep,"'cles on the b..~~ map. A a"",ber nf reference moOu-
<br />
<br />this report.
<br />
<br />"'eots On the same dat= as the base maps ar~ tn pla~,> alooi: eaQh study react
<br />
<br />Hydrolo!!:y
<br />
<br />and can he used for this purpose. The elevation, ftel<'! l<'!entHication,
<br />
<br />Peak dischar~c-frequen~y <lata used 1n this study _re develo!><,d from
<br />
<br />lo<:aU"n and descrtpUon af these mon"men~s are described in Table 2.
<br />
<br />rei'(re",lonequations1n the publication "Ra1nfall-RunoffModeltlljl;a ndPrel1-
<br />
<br />C. 1'l0odedAreas
<br />
<br />mlnary Regional Flood Characteristics of Small Rural Watersheds ln the
<br />
<br />The floaded Area "'~ps, plates I throup:h q. sho,", th~ bou.ndary of the
<br />
<br />A.rkansas Rtv..r Bastn in Colorado, 1981". This Is information developed by
<br />
<br />lOO-yearandSOO-yearfto"dplains. Thefloo<!plainboundar:te8wereplotted
<br />
<br />the U.S. Geolo~teal Surve)' to cooperation wIth the Colorado Department of
<br />
<br />fram the flood proftles hy determining the channel stattonio!: of floo<! cen-
<br />
<br />Hi~hways and Federal Hi>:hway Administrstion. The regr~ssion equations used
<br />
<br />tours at the S"",e Interval a"the to[>ograph1cmaps. Floodeontours,lIholln
<br />
<br />I
<br />!
<br />
<br />are:
<br />Ow '00 '0 ."'
<br />-
<br />025 - ",0 Ae.97
<br />Q" I, 140 A~ LOl
<br />-
<br />0\00 . '"~ ",,1.07
<br />, <,))V
<br />
<br />as wti'(i'(ly lInes, extend I>"-rpendleull1r to the ,Ureetton of no,", and intenect
<br />
<br />the ~round at the ed;;e of the floo<1.platn.
<br />
<br />The "r..a~ Indwi"rl "Hhin th~ f1"od line houndari.." ~r.. ~hout 700 ,,~rc~
<br />
<br />!orthe IOCl-yearfrequency""d7SSac""s [ut.th,,:;OO-year.
<br />
<br />Upon official approval of thts report by the Co10ra<1.0 Water
<br />
<br />0S00 - Based en Ext~naion of Fre~ueney LIne
<br />(A.. - Conttibuttng Drainage ~ea - Sq. ~i.)
<br />
<br />COMervatiotlllo,Hd, the area outlined by the 100-y.."r fl"od boundary may he
<br />
<br />regulated 8~cordlngly by the local offiCials.
<br />
<br />Thin procedure establhhed the. lower sej{T1l..nt of a cur"e relating drdo-
<br />
<br />D. Flaod"ay
<br />
<br />a~e at"a ~a peak d1sehar~... Th.. "!>per part of th" curve Is an extension ef
<br />
<br />E.ncraach..ents On flood pldn~, ~\leh ~~ "Htftdal HII, ~"n red"".. the
<br />
<br />the lOl<er "">:....ot at a .lope paullel to a ane developed ftOlll "Manua.! for
<br />
<br />are"l extent of a flood plain tf provlaton~ are mad~ for Increased flood
<br />
<br />P."timatinr, Flo"d Characteristics of Natursl-Flol< Stream" in Calorado _
<br />
<br />heights. As an alt"roattve ta the pr"."ot nooding sttllatior. 1n 1,imon, ~
<br />
<br />Technical ManU>ll No. 1'".
<br />
<br />"
<br />
<br />"
<br />
|