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3.1 Hydrologic Analyses Hydrologic analyses were carried out to establish peak discharge- frequency relationships for each flooding source studied by detailed methods affecting the cOllllllUnity. Cornet Creek is ungaged and the gaging station on the San Miguel River near Telluride has only a five-year record (1961 to 1965). The gaging station on the San Miguel River near P1acervil1e has a 40-year record. In order to have a consistent hydrologic analysis within San Miguel County, a regional relationship developed by the study contractor relating basin area to peak discharge was the method used for the San Miguel River. Gaging stations within hydrologic area No. 10 of flood frequency Region B (listed below) were used to establish the regional relationship. USGS Drainage Length Station Area of Record Period of No. Station Location (sa. mi.) (vears) Record 091450 Uncompahgre River at Ouray 44.0 14 1911-1924 091460 Uncompahgre River below Ouray 76.0 16 1914-1929 091464 West Fork Dallas Creek near Ridgeway 13.2 15 1956-1970 091465 East Fork Dallas Creek near Ridgeway 16.8 16 1948-1970 091650 Dolores River below Rico 105.0 25 1952-1976 091681 Disappointment Creek near Dover Creek 145.0 19 1958-1976 091720 Fall Creek 2.7 miles upstream from the mouth 33.5 18 1942-1959 091725 San Miguel River near P1acervi11e 308.0 40 1930-1976 091745 Cottonwood Creek near Nuc1a 43.0 10 1942-1951 091750 Naturita Creek near Norwood 27. 7 12 1942-1952 091755 San Miguel River at Naturita 1,080.0 48 1918-1976 091775 Taylor Creek near Gateway 12.0 26 1945-1967 The method developed by the U.S. Water Resources Council (Reference 6) was used to determine the floodflow frequency relationship based on log-Pearson Type III distribution for each selected gaging station. Gaging stations which have 10 or more years of record, and stations where peak flows are not affected by regulation and diversion were used for developing the regional relationship. Because the annual peak discharge published in the USGS Water Supply Papers (References 7, 8, and 9) and the USGS Surface Water Records (Reference 10) were a mixture of floodflows caused by snowmelt and rainfall events, the regional relationship established by using these annual peak discharges does not reflect intense rainfall-produced floods. A more detailed method was used for each gaging station to develop regional relationships for this area. The procedures were as follows: (1) the rain and snowmelt data 8