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<br />I
<br />I
<br />I
<br />I
<br />I
<br />I.'
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />II
<br />II
<br />
<br />10 year - 10,100 c.f.s.
<br />50 year - 18,200 c.f.s.
<br />100 year - 22,400 c.f.s.
<br />500 year - 33,500 c.f.s.
<br />
<br />HYDRAULIC ANALYSIS
<br />
<br />GENERAL
<br />Malta is located in Phillips County on the right bank of the Milk
<br />River. Vat.r surfac. profil.s for the hydraulic analysis w.r. computed
<br />using the HEC-2 Backwat.r program on the Harris 500 comput.r. Cross
<br />sections for the model were obtained from FEHA as used in the May 1987
<br />Flood Insurance Study (FIS) for Malta, Montana. The "n" values used in
<br />the Malta FIS were 0.045 for the channel and 0.055 for the overbank. Con-
<br />traction and .xpansion coefficients of 0.1 and 0.3 were us.d .xc.pt for
<br />the bridges, where 0.3 and 0.5 w.re us.d. Th. starting wat.r surfac.
<br />.levations were calculated using the normal depth ..thod as in the FIS.
<br />Th. discharg.s calculat.d in this analysis w.r. gr.at.r than those us.d
<br />in the FIS. Tabl. 1 compares the discharges between the two studies.
<br />Initial examination indicated that th.r. were no ic. problems at Malta.
<br />Verification will b. made in the DPR.
<br />
<br />':,:' :':'::';'::;j:;:'::;:::;'::;::::::':'::;'::::h::::::::::::', :':;:./::::'::::J?:':';=::')'::::i:;::-'::::='=;::::),/r:::::;-'/;:;:::\=;=):;!;;:;:;::;::;:::::::??:'?\::T':\!::.:-:t::;';:,:-" -: ':-_'-:;}>::;:::::::;:::n::;:::::"\I\\:;::: :::::-:',: t:tiii/I{t):;?:;;:;:;?{::::::::::,?:-:-:---....
<br />- , .':-- ;.:----:' :::: :': -:' " --.- .:' -- c,- ,':-"-','-', :--- -----,-:-.- -' '. ,.........., , , ,-.:-.-.:.. -t - br.... '1'--- :-' ,.'--,' ,-, ..-, , ", - : ':', ,," ,.... ii(;::///'(: _':::'-':: :'.J'" .
<br />
<br />..'. .......}....\\..".....\.~~~fi~~~~f,,~b1~i~~~~i~~.~~t ,.",.,.. ..,.,..., ,..
<br />
<br />.'...'....'................. ...../\..}............ /\'....\\(~l1:..,ft~;A!I\} lI,lico~i.saric..'....~.p.i4ii} .., ,.'...,....
<br />.", '-',,''':'-'-'.'.' .;-c.: ,-:,:-. ::---.::::<,}::)::::):~:::::::::::;j:;;::-:}>::::::-;-;-'-; -';"';':';':::';::":':"":::: ;:.>}::' :::.::::;:::::::::::::::HL~:.:.:.:-;--.....
<br />
<br />.-.-.-.-:-,-:,:,:::.:.:,:'..,:.:.:.:..,-.....
<br />
<br />" ",.-,_...::.---- .'-"-'-".-,-,..- ,--.:-,-'-,.,'----",' ...........,.;,:;..:..-:-.--:...,'......:..-,..
<br />. ... ..........'.,.............,...............'......Ei7.iii::........'.. ..'...............}..Ftll........'
<br />
<br />. ' . .,'...... .".l~;~~~.).
<br />
<br />,. - C'- _ ,. .
<br />.'.',..-..--.".'.'.'." . "..,.",.".".'.,.".",..,.,'..".- '-., ',.,,"-.-,..',.',.,.....',.,.-..'-,'.'.'..'.',..,..',.".,...,.
<br />.,...\.......i(ll.c~2(l~;f';tr.."s~X......... .'
<br />
<br />...1'.0..Y'..' ",..
<br />.......\ -ear..
<br />50-Year,
<br />lOO-Year.
<br />'.\500~Year
<br />
<br />\~ ,900 .......... .
<br />.,.....11,.650
<br />.21;600
<br />\32/300
<br />
<br />.'...10..100 ...
<br />, . . 18,200
<br />22,400
<br />33.~OO
<br />
<br />
<br />
<br />14
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