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. lOO-year Peak Flow Estimates for Selected Streams in Morgan County Drainage Area lOO-year Peak Stream Name Location (sq. mi.) Flow (cfs) Kiowa Creek Upstream of Hwv 76 at Wiggins 709 49,350* Wildcat Creek At confluence with South Platte River 125 16,650** Beaver Creek Brush, Colorado 1089 55,000*** Badger Creek Brush, Colorado 277 30,000*** * ** *** Obtained from "Floodplain Information Report, Kiowa Creek at Wiggins, Colorado," Estimated using the CWCB regression equation for subregion SPL-I Obtained from "Floodplain Information Report, Beaver Creek, Brush, Colorado," There are numerous other streams within the county having drainage basins of various sizes, Peak flows may also be estimated for those streams using the subregion SPL-I regression equation, providing that their drainage areas fall between 2 and 1090 square miles, The lOO-year flow for approximate floodplains of streams that have drainage areas between 0.5 and 2 square miles can be estimated using the USGS publication entitled "Techniques for Estimating Regional Flood Characteristics of Small Rural Watersheds in the Plains Region of Eastern Colorado." That publication is available from the USGS publication center in Denver, Colorado, . A detailed study or other hydrologic analysis must be performed for projects involving streams with drainage areas that fall outside the applicable range of the two methodologies discussed above, The Guidelines methodology is not appropriate for development involving residential subdivisions greater than 50 lots or occurring on sites greater than 5 acres, commercial construction, industrial construction, construction of public facilities, or construction of flood control facilities. The hydrologic methodology developed in the Guidelines is appropriate for designation and approval of approximate floodplain information and for use in simple floodplain analyses for development such as open space, agriculture, farm bridges, pole bams, and individual residential structures, A procedure for determining hydrology information for approximate floodplains of lakes, ponds, local drainages, and overflows from irrigation canals and ditches has not been established. Hvdraulic Analvsis The approximate floodplain delineations in the FIS for the South Platte River are based on the information contained in the 1977 Corps study, Hydraulic methods used for the approximate floodplain delineations of other streams studied in the Morgan County PIS are not available or have not been documented by FEMA, For future studies, an approximate lOO-year flood elevation at a particular location on a stream of interest may be obtained by using an appropriate lOO-year peak flow value in conjunction with an acceptable hydraulic analysis, An appropriate peak flow value may be obtained or estimated using the information described in the previous section, Hydraulic analyses for determining lOO-year water surface elevations for approximate floodplains may be . performed using FEMA's Quick-2 computer program, the Corps of Engineers' HEC-2 computer 5