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. FLOOD HISTORY This section presents general data on past floods and descriptions Df selected floDds to show the nature of the floDd problem. CACHE LA POUDRE RIVER BASIN Stream capacities on the Cache la PDudre River range from about 5,000 cubic feet per second (c.f.s.) near Fort Collins to about 3,000 c.f.s. at Greeley. Streamflow records from the U.S. GeolDgical Survey (USGS) gaging statiDns on the Cache la Poudre River upstream from Fort Collins and downstream from Greeley, supplemented by data collected by the Colorado State Engineer, indicate that 27 floods of varying severi- ty have occurred since 1882 in the vicinity of either Fort Collins Dr Greeley, or both. In additiDn, majDr floods on the main stem are known to have occurred in June 1844, June 1864, and May 1876; however, peak discharge estimates for these floods are not available. Peak dis- charges for historical flDDds since 1882 are shown in table 4. In addition to floods on the main stem, it is known that flooding occurred due to runDff frDm small canyons in the Fort Collins area during 1 through 4 September 1938. High d,ischarges occurred on 31 July 1976 on some minor tributaries in the foothills region of the Cache la Poudre River basin because of heavy rainfall that caused :he Big Thomp- son River flood. Localized flash flooding occurred in Larimer and Weld Counties on 24 and 25 July 1977 due to heavy thunderstorm rainfall. Local streamflow records extending back to 1904 were obtained by the Soil Conservation Service during its studies of the Boxelder Creek watershed. These records indicate that some flooding Dccurs in the watershed every 2 years on the average and that large floods occurred on Boxelder Creek in 1904,1909,1922,1930,1933,1937,1941,1947, 1961, 1963, 1965, 1967, and 1969. In May and June 1976, two storms caused $46,100 in damage and took four lives in the Wellington vicinity. 14 .