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. Thompson River, Big Thompson River below Lake Estes (17 years), Big Thompson River above Lake Estes (27 years), and North Fork Big Thompson River at Drake (30 years). The gage records were analyzed using the log-Pearson Type III distribution as recommended in the u.s. Water Resources Council Bulletin 17 (Reference 9), and the dis- charges were adjusted as recommended in Technical Manual No.1. . . . . The Storm Water Management Model (Reference 10) was used to deter- mine discharges on drainage basins that are representative of the smaller Big Thompson River and North Fork Big Thompson River tribu- taries. These discharges were plotted on semi-log paper to develop discharge-drainage area curves for the region. These curves were entered with the drainage areas of the smaller tributaries and the appropriate discharges were tabulated. ~ Discharges for the lower portion of the Big Thompson River near Loveland were provided by the u.s. Army Corps of Engineers in their Flood Plain Information report published in 1971 (Reference 11). . The discharges for Buckhorn Creek and Redstone Creek were calculated based upon the regression equations found in Technical Manual No. 1 (Reference 8). Parameters needed for the regression equations were taken from u.s. Geological Survey topographic maps at a scale of 1:250,000 (Reference 12), u.s. Soil Conservation Service County Soils Maps (Reference 13) and County Land Use Maps (Reference 14). Discharges for each design point were calculated for the portions of the basin above 7500 feet and below 7500 feet, and the largest discharge at each point was used. The U.S. Soil Conservation Service performed the hydrologic analyses on Box Elder Creek while compiling their Watershed Work Plan (Refer- ence 7). Precipitation values were taken from National Weather Service Technical Papers 40 and 49 (Reference 7). Soil information was taken from an unpublished detailed soil survey completed by the u.S. Soil Conservation Service for Larimer County. The U.S. Soil Conservation Service's Technical Release 20 (Reference 15) was used to develop and route hydrographs based upon the information gathered. The U.S. Soil Conservation Service's computed discharges on Box Elder Creek were based upon none of the proposed reservoirs being completed and all three proposed reservoirs above Wellington being complete. At the time of this study, only two of the reservoirs had been constructed, so the assumed storage for the third structure (B- 2) was eliminated based upon the information supplied by the U.S. Soil Conservation Service. The discharges for Dry Creek were determined based upon methods presented in Section 4 of the U.S. Soil Conservation Service's National Enqineerina Handbook (Reference 16). Unit hydrographs were developed from basin information taken from U.S. Geological Survey ~ 11 - .