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cottonwoods, wi llows and siberian elm. The meandering channel, passing through cropland, provides a diversity in landscape. The lush vegetation in the floodplain contrasts vividly surrounding barren hills. This diversity enhances the visual aesthetics and wildlife habitat values. to the , area s The floodplain supports a variety of wildlife species, sucJ\ a~ mule deer, coyote, cottontail, red-winged blackbird, blue heron, song sparrow, black-headed grosbeak, red-tailed hawk, golden eagle, bald eagle, Canada goose, mallard, and many other specie~ of wildlife. These riparian areas are very important in the arid regions of Colorado. The proximity to water and robust vegetation supported by the water regime attract more species of wildlife to this habitat than any other in western Colorado (Reference 3). 2.3 Principal Flood Problems Major flooding along Roan Creek is caused by rapid melting of the mountain snowpack during late May to early July, as well as summer rainstorms. There is also the potential for flooding as a result of rainfall occurring on melting snow. The snowmelt floods are characterized by moderate peaks, large volumes, and long durations. The summer floods have characteristics of high peaks, and short flow durations. The most recent damaging flood on Roan Creek occurred at the end of May 1983. It resulted from the melting of an unusually deep snowpack. The above-average spring runoff caused concern all along the Colorado River, including the large Glen Canyon Dam (Reference 4). Roan Creek area residents reported that water begari to rise on approximately May 15 and remained at a high stage until June 6. Approximately 10 families along the creek were affected. Local irrigation systems were washed out, making it impossible for ranchers to irrigate. Approximately 200 acres of irrigated pasture and hayland were damaged with debris, sediment, scarring, and streambank erosion. Approximately 50 percent of the total crop production in the Roan Creek watershed was damaged, along with 12 miles of county roads and 3 bridges. Total damages were estimated at over 1 million dollars. Streamgages on Roan Creek were discontinued in 1982; therefore, the peak discharge for this flood was not determined. The following lists discharges in cubic feet per second (cfs) for other events of significance on Roan Creek (Reference 5). May 11, 1980 - discharge 2,020 cfs May 19, 1979 discharge 1,190 cfs Sep 19, 1972 discharge 1,900 cfs Aug 20, 1971 di scharge 1,000 cfs May 26, 1967 di scharge 1,220 cfs May 21, 1922 discharge 1,110 cfs 4