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~pe~ifically for the Coloi'ad~ and Manitou Springs area. Notes and field maps are on file in the Colorado District offi~e. In Cook Creek tButler Canyon) just north a2 Palmer Lake evidence of significant flooding ends at about 7,900 feet. In an unnamed tributary to Carpenter Creek, ju~t south of Cook Crzek, evidence of significant flooding ends at ahout 7,750 feet. In Horth~Monument Creek and its foothill tributaries, there are flood deposits in the channel up to the Lower Reservoir at an elevation of 7,500 zeet. Because the Lower and Upper Reservoirs could have an effect on flood deposits, earlier investigations were made in rlonument Creek and tributaries upstream from the reservoirs. There was no evidence of significant out of bank f1~WS. REVIEW OF LARGEST FLOODS IN EL FASO COUHTY AKD VICIHITY ~~~ Historic, streamflow-ga~ir~g ~tation, and miscellaneous flood i~ec~rds were revicwed to determine the largest floods and to define an elevation limit to significant z•ainfall runoff in E1 Paso County. The primary souices tor hi5toric floo~ informatiun are in Follansbee and Sawyer (1948? and the tw~ flood-plain informati~n reports for Fountain Creck (U.S. Army Carps of E:ngineers, 1974; U.S. Federal Emergency Management Administiatiun, 19~i3>. The~e reports indicate that there have been sEVeral flash floods in Manitou Springs in the past 100 years. In 188~ a cloudburst caused flooding on Williams Canyon, lower Ruxton Creek, and Fountain Creek. In 1894 heavy rain caused lesser ~l~odiizg on the same creeks. In 1947 a flash flood occurred on Williams and Waldo Canyons. The discharges associated with these floc~ds can not be determined 1`rom the reports (and is one reason for the paleoflood investigations). HoWever, it appears that the 188~ flood was the largest. All flo~d :eports indicate changing channel capacity with time and that charinel obstructions (particularly bridges and cuivei-t~) cause flood ~epths to be locally higher and cause water to tlow down streets making the floods appear larger. It must be recognized that when bridges were washed out in these historic flaods they generally were much low~r in the channel. Also, in many cases, these were wooden bridges (logs With planks> across the low-water channel; hence, were suseptible to washout with even small floods. The maximum flow recordeci at streamflow-gaging stations and the ma~:imum indirectly measured floods (when streamflow conditions pr?clude direct measurement a2 floods) in E1 Paso County were ~urnmeii~ed. Also cupiea af etreamslow rec~rds cullected by ±he Southern Colorado Power Company, generally from 1905 to 1950, Were available in discontinued station files in the Colorado District office were reviewzd and summari~ed (several•of these records were summarized monthly flows and c.ould not be used to determine the peak flaW). A list o2 all Colorado streamflow-gaging stations is provided which shoWS the peiiod of recoz•d for each station. Also included are the indirect discharge measuY•ements available in E1 Paso County: These streamflow records are ~~rovided as an attachment. The maximum streamfl~~w for these locations are summarized ~raphically in Figures 3 and 4. Both these graphs sho~r that thz magnitude of floods decrease ~ ~.