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due to rainfall were separated. Using log-Pearson Type III distri- bution, the 10-, 50-, 100-, and 500-year recurrence interval discharges were obtained separately for snowmelt events and rainfall events (Reference 5). The data showed that, except for small drainage basins (less than 10 square miles), the snowmelt events yielded higher discharge peaks than the rainfall events for the flow frequencies used in this study. Using snowmelt event gage records, regression equations were developed for the 10-, 50-, 100-, and SOa-year recurrence interval discharges as a function of drainage area. Flood discharges for Meadow Creek were determined by modifying the drainage area-discharge relationships to include the effect of rainfall events on smaller drainage basins using a synthetic hydrograph approach. A detailed description of the hydrologic analyses for this study is covered in a technical addendum entitled, Hydrology Report, Flood Insurance Study, Summit County, Colorado, submitted to the Federal Insurance Administration and the Colorado Water Conservation Board (Reference 6). Peak discharge-drainage area relationships for Tenmile and Meadow Creeks are shown in Table 1. Table 1. Summary of Discharges Flooding Source and Location Drainage Area (Square Miles) Peak Discharges (Cubic Feet per Second) la-Year 50-Year laO-Year 500-Year Tenmile Creek At Lake Dillon Below North Tenmile Creek Gage No. 501 Above Confluence With North Tenmile Creek 94.2 1500 1820 1980 2190 93.3 1450 1780 1900 2130 79.0 1335 1590 1710 1910 Meadow Creek At Lake Dillon Upstream From Confluence With South Fork Meadow Creek 5.8 125 175 280 340 4.7 110 160 230 330 3.2 Hydraulic Analyses Analyses of the hydraulic characteristics of streams in the community were carried out to provide estimates of the elevations of floods of the selected recurrence intervals along each stream studied in the community. 5