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<br />was reported to be a mile wide in places, Numerous rural homes were flooded, many swept from their
<br />foundations, One mile of U,S, Highway 34 west of Loveland was washed away, Irrigation works, such as
<br />diversion dams and canals, were destroyed, crop loss was heavy, and there was much sedim,mt and erosion
<br />damage, The lives of four people were lost and many were 1'3ft homeless, Total damages from the flood were
<br />estimated at $602,000,
<br />
<br />Flood of July 1976, Heavy rainfall, amounting to as much a~; 12 inches in 4 IlOurs, fell on th" ev"ning of 31
<br />July in the upper Big Thompson River basin in the general vicinity of Estes Park, Glen Haven, and Drake, Th"
<br />intense rainfall produced large amounts of runoff on tributarl"s of the Big Thompson River as well as on the
<br />Big Thompson River itself. Flash flood conditions prevailHd from the rainfall area downstream to the mouth
<br />of the Big Thompson River canyon west of Loveland, The estimated peak discharge at the U,S,G.S, stream
<br />gaging station located on the Big Thompson River 6 miles east of Drake was 31,200 cfs ' about 4 times larger
<br />than the previous recorded peak discharge, It is estimalEld that the drainage area contributing to the flood
<br />hydrograph at the canyon mouth was about 70 square milHs out of the total drainage area of 304 square miles
<br />at this point. Damages from this flood were estimated at about $35,000,000 in Larimer County and about
<br />$45,000 in Weld County, One hundred thirty-nine bodies were recovered in the flood aftermafh with six persons
<br />listed as still missing,
<br />
<br />4,1.13 CACHE LA POUDRE
<br />
<br />Flood History, Annual peak flows on the Cache la Poudre River normally occur in the period May through
<br />September, with about 70 percent occurring in June, Althougll most floods result from intHnsH rainfall in the
<br />basin, snowmelt runoff is a factor and the worst potential flooding condition is that of heavy rains at a time when
<br />snowmelt runoff Is highest, in Mayor June, Notable floods on the Cache la Poudre River in the study reach
<br />occurred in 1844, 1864, 1884, 1891, 1904, 1923, and .1930, There were apparently three large floods of
<br />comparable size in 1864, 1891, and 1904, All of these floods peaked nHar 21 ,000 cubic feet per second, The
<br />1904 flood was probably the worst flood in terms of dollar damages,
<br />
<br />Flood of 1844, Although it is known that severe flooding occurred In the basin in 1844 as a result of heavy
<br />snow cover and intense rainfall, the area was so sparsely settled at that time that no accurate record was made
<br />of the effects of the flooding In the lowm basin, One description of that flood was in a letter written by Antoine
<br />Janis, a French trapper on the river near the present site of I_aporte, He wrote "On the first day of June 1844,
<br />I stuck my stake on a claim in the valley, , , At that time the streams were all very high,"
<br />
<br />Flood of June 1864, An extra heavy snowpack augmented by a rainstorm on 9 June 1864 resultHd in further
<br />flooding on the Cache la Poudre River. Historian Ansel Watrous wrote of the 1864 flood:
<br />"Fort Collins",,, owes its origin and first place on thE' map to the intervention of a flood in the Cache la
<br />Poudre River. This flood occurred on the last days of May and first days of June 1864, and is said to have been
<br />the worst known by white men, The water inundated th'l valley from bluff to bluff with a torrent that carried
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<br />Colorado Flood
<br />llydrology Manual
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<br />4,16
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