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<br />.
<br />
<br />.
<br />
<br />.
<br />
<br />""liJchin the Bear Creek cloudburs",:; center. Hov.rever, it V[c.s estim8.tecl t,}lnt
<br />
<br />7.9 inches cf rain fall there in 6 hours, of which the gruo.tcr portion !:'"ll
<br />
<br />bet.ween 6 P.M. and;) P,M.. Very 11eo.-1,J' rainfall also oc'currocl i~1 tllfJ foot-
<br />
<br />hills ~101.th and we3t of Colorado Springs during tho eveninG: of' Soptembur 2,
<br />
<br />Floods of Record
<br />
<br />35. Gene~. The 30',1th Platte l1iiTer basin is subjeot to floods of
<br />
<br />bvo typos t sustained K1'd flash floods. The forlaer cenerally occur dllring
<br />
<br />the period fray,; April t;,rou:-.,h June as the result of ex'::ensive rainfa.ll com-
<br />
<br />bined \yith snovrnelt. Such floods usually are ceneral thrciUchout the mojoX'
<br />
<br />portion of the watershed.
<br />
<br />The latter occur any tiNe during GllO pOI'io(l from
<br />
<br />I,!ay through September. They are caused by YC'ry inte>ns8 rainfalls, which
<br />
<br />usually oocur over limited areas. They are charc.ctcrized by hiSh instan-
<br />
<br />taneous discharges and low voltunes) the pea::s being quickly l'ed,llCed by ve.ney
<br />
<br />storage end by iri:~if.io.tion diversions as the flood pro~reSD dmvnstreem.
<br />
<br />36. Tho major floods of record in the basin are sUl1lrcmrizod in table 11
<br />
<br />according to type of flood and portion of basin uffected, and are discussed
<br />
<br />below.
<br />
<br />-ro, }hxLr:lumT---- ._~-,
<br />I peak ! Tctal
<br />I discharge I volume
<br />Is-6-".-ft. lacre-fe-6t
<br />-1--.-~ ~--j.,.-----
<br />. ' I
<br />* 100,000
<br />*p 13,200
<br />p 8, 700
<br />11,000,'
<br />31,000
<br />*p 12 ;000 :
<br />,
<br />9, GOO I
<br />8,600 i
<br />20,000 I
<br />57,000:
<br />4 "tr' i
<br />,'" ;,:.J 1
<br />,9,400
<br />8,000
<br />6;320
<br />8,790
<br />P 31,000
<br />30; 800
<br />22,000
<br />7;600
<br />10;200
<br />3,000
<br />
<br />TABLE 11.
<br />
<br />Ihjol" floods of record in Gouth Flatte River basin,
<br />
<br />:---
<br />,
<br />
<br />Flood
<br />Date
<br />
<br />Ste,tion
<br />
<br />Typo
<br />
<br />StroDJ+l
<br />
<br />I
<br />
<br />I Aug,
<br />-, June
<br />June
<br />June
<br />June
<br />July
<br />May
<br />~;D.y
<br />June
<br />July
<br />July
<br />June
<br />June
<br />June
<br />Juno
<br />June
<br />June
<br />May
<br />July
<br />
<br />1844 I sustained South P1o.tte I~iV'cr l Above Denver
<br />1876 :sustoined Coal Creek Erie
<br />188G !flash Clear Creek Golden
<br />1894 'sustained South Platte River Denver
<br />1894 isustained South Platte :(i ver Ft. I:iorc;un
<br />1894 i sustained Boulder Creek Boulder
<br />18911sustaincd St. Vrain Creek Lyons
<br />189G :flo.sh 'I Bear Creek- I.iorrison I p
<br />1904 iflash Cache la POUdl'e River Livermore I p
<br />1904 flash ICo.chC la Pcudre 2i,ver Canyon mouth *p
<br />1917 ,flash : Cache 10. Poudre j,iverl Greeley p
<br />1919 'I flash 1St. Vrain Creek I Lyons
<br />1919 ,flash BiZ Thompson Ri1er Dral:e (1) p
<br />1921 Isustained I South Platte Ri.,-er Seuth Platte p
<br />1921lsustained Soutll Platte River Denver
<br />1921 sustained I South Platte River Kersey' I
<br />1921 sustained,South Platte River Ju1esburg
<br />1921 sustainod! South ?latte River Ncrth Platte'\
<br />1921 sustnined,Big Thompson River At mouth *p
<br />1930 flash I'Cache 10 ?oudre River Canyon mouth I *
<br />1933 flash Bear Creek Mouth I p
<br />
<br />- -
<br />
<br />.iI,900
<br />
<br />2,900
<br />139 ;000
<br />200,000
<br />700;000
<br />634,000
<br />
<br />23,200
<br />4,()()0
<br />
<br />~,~)ji:..- ;Jj.;eP"'-"-.i-.;..~i~:;:2-;i~;"'~~:-;-2-~::'--ji~'_'~4.::'<v::i';';";bJ.;ii$j,,-:i'b~''';_'--:'""---';;:.;;-':~'--~'-__~,_il,~,';~"_;.:._ -~ad- ~:*,o_~~'i.,,-,~^~,,;~~,,---"- ,,,x ,,;y,-,..;..:"'~>Sr:. -,~-~~'';'''K>-:-~
<br />
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