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u.s. Environmental Protection Agency (BPA) Storm Water Management Model (Reference 37). MITCAT was used to model the 400-square-mile mountainous area upstream from Golden; the Storm Water Management Model was used to model the lower 175-square-mile plains basin. Rainfall values used in the models were obtained from the Precipitation-Frequency Atlas of the Western United Statesll Volume 1111 Colorado, published by the National Oceanic and Atmospheric Administration in 1973 (Reference 38). The hydrologic analysis for Bear Creek was performed by the USACE, Omaha District (Reference 24). The Bear Creek Dam and Reservoir intercepts flows from 239 square miles of the total 261-square-mile drainage basin. The remaining square-mile drainage area below Bear Creek Dam still has the potential of generating damaging runoff flows during a cloudburst event over the lower basin. No applicable runoff records are available through this reach because of the recent construction of the dam. Therefore, discharges for the 22-square-mile drainage area below the dam were developed by using the EPA Storm Water Management Model (Reference 37) with modifications by the Missouri River Division of the USACE. These discharges were computed assuming full basin development. Peak discharges for Cherry Creek were previously determined as part of the July 1976 UDFCD Flood Hazard Area Delineation report for Cherry Creek (Reference 10). Those discharges were computed using the EP A Storm Water Management Model (Reference 37). The Cherry Creek basin was assumed to be fully developed. Peak discharges for Lakewood Gulch and Lakewood Gulch Overflow were previously determined as part of the 1976 UDFCD major drainageway planning- report (Reference 39). Those discharges were computed using the Colorado Urban Hydrograph Procedure as outlined in the Urban Storm Drainage Criteria Manual (Reference 40). Split flows were calculated along Lakewood Gulch in the reach between Decatur Street and the South Platte River. The divergence of flows from Lakewood Gulch at Decatur Street is referred to in this study as Lakewood Gulch Overflow. Peak discharges for Dry Gulch (Lakewood Gulch Tributary) were previously determined as part of the 1977 UDFCD Flood Hazard Area Delineation report (Reference 12). The Colorado Urban Hydrograph Procedure (Reference 40) was used to compute the 10-, 2-, and 1-percent-annual-chance events under fully developed basin conditions. The 0.2-percent-annual-chance flood peak was obtained by extrapolation from the frequency-discharge curve. Peak discharges along Harvard Gulch, Harvard Gulch Overflow, Dry Gulch (Harvard Gulch Tributary), and West Harvard Gulch were determined as part of the 1979 UDFCD Flood Hazard Area Delineation report (Reference 14). Those discharges were computed using the Colorado Urban Hydrograph Procedure (Reference 40). 15