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The ~agle River has a large, braided channel approximately 5 feet deep and 80 feet wide. Its slope is approximately 25 feet per mile. The flood plain, covered with cottonwood trees and pasturelands, is approximately 200 feet wide at Eagle. Eby Creek flows ~ntermittently ?outh out of the hills east of Eagle. The narrow, deep channel is well defined throughout the studied segment, and the flood plain ranges in width from 30 to 60 feet. The primarj underlining soils in Eagle are of the Hapluatolls- Haplargids-Calciustolls association. These soils are shallow to moderately deep, and well drained (Reference 3). 2.3 Principal Flood Problems Flooding along the Eagle River, Brush Creek, and Eby Creek in Eagle normally occurs from May through September. Floods can occur from runoff, snowmelt, intense rainstorms and cloudbursts, or rainstorms augmented by snowmelt. Past floods in Eagle on both the Eagle River and Brush Creek occurred in June 1947, June 1957, June 1959, August 1965, August 1968, and ~~y 1970. The latter flood is the most recent flood of record. All of these floods caused minor damage and erosion problems. There were no recorded or estimated discharges at Eagle (Reference 4). 2.4 Flood Protection Measures There are no known flood protection measures in the Town of Eagle. 3.0 ENGINEERING METHODS For the flooding sources studied in detail in the community, standard hydrologic and hydraulic study methods were used to determine the flood hazard data required for this study. Flood events of a magnitude which are expected to be equalled or exceeded once on the average during any 10-, 50-, 100-, or SOO-year period (recurrence interval) have been selected as having special significance for flood plain management and for flood insurance premium rates. These events, commonly termed the 10-, 50-, 100-, and 500-year floods, have a 10, 2, 1, and .0.2 percent chance, respectively, of being equalled or exceeded during any year. Although the recurrence interval represents the long term average period between floods of a specific magnitude, rare floods could occur at short intervals or even within the same year. The risk of experiencing a rare flood increases when periods greater than 1 year are considered. For example, the risk of having a flood which equals or exceeds the lOO-year flood (1 percent chance of annual occurrence) in any 50-year period is approxi- mately 40 percent (4 in 10), and, for any 90-year period, the risk increases to approximately 60 percent (6 in 10). The analyses reported here reflect 4