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<br />B28
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<br />FLOODS OF 195,,) IX THE UXITED STATES
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<br />SorTI-I PLATTE RIVER BASIN, COLORADO, .Jt,"NE 1965
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<br />B29
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<br />Plum Creek. \yere left a fft.'I' lalld h~HllJi..'ell washed awnv, ::\fucl1 of the
<br />tmYll of (',\;tle Roek W<1:..; iilllli.da{ed~ and telephone .~e~J'\'iL'e to about.
<br />100 phones in the tOWll was disrupted, Seven hOllWS. ;1 church, the
<br />gr~lllge hall, and the ]0\\"('1" part of th.e main street ill ~p(lalia \-,lllished
<br />during the flood.
<br />The Derp:er :lnd Hi~': {~:';lndc ~~~:.':..;L_'i..jl H"il::-nad br-t"'\"f-~-'n Dt-ii..-er alh1
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<br />~1;
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<br />..
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<br />Palmer Lakp was huilt in lS71--7~ and had 11cn'r UC'Pll d:t111aged :b
<br />('x((,llsi\"l'ly a~ it '\':1:"; ill l~t(;:I, Fi\"l' Lridgl':";, mallY ('til\"l'rh. alld~ aJ)lIllt
<br />.J. miles of tra('k w('re danl<lf!C'(], Hepairs to Rio Grande fa('ilitit'~ ('o~t
<br />S4GS,OOO, 'I'll(> .Atchisol1. Tnprk;l, 8: ~;llltn. Fe H:ni]ro:ld ,lbo ful1o\\-::-; dll'
<br />:-)oltl h Platte Hi \"l't' :llHl Plulll Creek. and l'('pair~. primarily to Oll.e
<br />bridgl'~ cost :\bout $;')00.000. The railroads worked together and were
<br />able to open the 'sant<l Ft' tr;lek to two-way traffic ill 10 (1:.1\"8. The Rio
<br />Gr,'l11{le t",'1cl,' \\-"'llt ;nt(, 'c",.;"" ,,"o"t H \\':el,'s "./:0.",-,. tl'le ~,o.(){!
<br />_ _ _ __ . ,,-.,,~ .." ;"' , ''-'--' 'J ,-. v '-- ull,--,-' . l.
<br />The floodwaters from Plum Creek SOOll t"xcceded the capa('it v of the
<br />main channei of the Sonth Platte Rin~l'l and residential. com;nercial.
<br />and industrial :-;tructures were flooded. Buoyant it(,lll~ st;eh as butane
<br />g-.lS storage tanks, hOll~r trailers, 11ll11ber. and truck yaIlS floated dowll-
<br />stream, plugged bl'idgc opcnillhTS, (fig'. 10) and iJattered ::;tI'uc! llre~,
<br />Bl'irhrp. encrillC>l:>1'C J'nH",.t t-J",+- snl""';"~ ,~O- 1-..:(1.-e h~'::._'_ /C,',' ,\L-''-ll"l"ll'
<br />-- --t:-- ..~.....,--." >''--1"''.' ''''''- ,--VLUI--Hts <ll l1~1 ~b I'll l~ I, < UUt ... \~
<br />was not a factor in any bridge failures, The primary causes \ycre the
<br />added thrust from the debris piled against the upstream side of the
<br />bridt:!e :,ul<l the increased ,\'ntt>:, pn?-5Si.l'I'e ;lg,~iHst the h!'idge. The
<br />impact, of large floatil~g objects \\.:15 part of the problem at sOlne
<br />bridges. Cross sections at bridges before and after the flood showed a
<br />net seour of as much as + feet in the bed of the channel under brid<Tes
<br />b
<br />supported by closely spaced pile bents and (or) solid piers. ~\t sites
<br />wlH'l'c hrid!!es are supported by two 01' three columns, little- or no net
<br />seou!" occurred.
<br />Repairs and replacement ofbl'idg-es amI high\\":lYs in the State Hi~h.
<br />way system nlone cost ~n million, The city and eonnty of Denyer spent
<br />all :ldditional $914~OOO on repair of thC'il' streets and bridges,
<br />.\hOllt 8,000 telepholles w('t'e put out of sen'ice by the flood in the
<br />metropolitan Deu"er area, Of thes~~ .\000 in -Littleton, En~lewood. awl
<br />south J)ell\-er were still out ~ dan~ after the flood
<br />The conditiolls in and Ilpal' hell\yer 011 the ll~orllillg afh'r the flood
<br />call be described. in many ways~ but the most SlICCillct ;111rl appropriate
<br />description is tIlat the. .south Platte Ri,-er nllley was a me~s. The city
<br />of I?~ln'er spent just ()\'(>!" $1 million ('lc>aning up Jllud and debris in
<br />addItIon to that .spent by other llIunicipalities, businesses. and
<br />indi\'icluals.
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<br />Flood damage figures h:l\'e been t'ollloiled bv the Soil C()l}SPIT:ltioll
<br />SelTice for th~ir Kio\\':! Creek 'Yaterslled P;otectioll Project which
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<br />FIGURE lO.-South Platte Ri..-er near '.Ye"t
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<br />n~n.l~~ "_n
<br />..uvu.t:".... ...........
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<br />Littleton, Colo.. on
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<br />morning of ,June 17, 100;:>. Dem'er Post uhotograph by Edward )Iaker_
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<br />is the 118-~quare~lllile basin above the town of l-ciowa~ Colo. The floods
<br />of June IVG;) were se\'eral times the size of the design floods for the
<br />project structures. .\bout 2,700 acres were flooded. and the tobI flood-
<br />water dama;!e tot'l'OpS, pasture, fences, li\yestock. :lIld roads and bridges
<br />al}d to other ftood.plain uses was about ~V~5,700. ~edilllent. deposition
<br />Oil about :n.) :HTf'S of ("rop f\lld pastul'elalld callsf>d damage of $10,GOO.
<br />Stl'cambank l'l'o::;ioll OlTtlrrcd along a total lineal distance of D,~ m.iles
<br />of the m.\in channeh:; of East and ""e~t lGowa Creeks and Kiowa
<br />Creek. _\lso. ;dJont ;{O acres of crop and pasturelnnd was a total 10S5
<br />from hp:l\'y Pl'll:-3iOll or streamhank cutting, Erosion damage amonnted
<br />to Sl+~7n()~ and tilt' total damage in the watershed was $l(ij,OOO. Total
<br />d;Ull:lg'P for the period H)J)r,-G4 was only $6,600.
<br />J):lllla~e l'au~ed by the Hood of June 15 in th... Bijoll Creek basin
<br />~.otdd not be determined because ,t more de\'asrating- flood occurred
<br />only +s houl'~ later, Some ]i\'estock were lost- during the .June Li flood,
<br />and on lower Bijoll ('reek in the early morning" of .TUlle 16 a rancher
<br />had to he rescued frolll his fencf'post ppr<,h ,yhpJ'f' f:l!'t.l'ising- \\'~l.te!'
<br />had trapped him.
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<br />333-521 0-69-5
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