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2.4 Flood Protection Measures No flood protection structures exist within the City of Wiggins. Although some levees exist along the east bank of Kiowa Creek to the south and west of Wiggins, these structures provide no protection from floods of a higher magnitude than the 50-year flood. 3.0 ENGINEERING METHODS For flooding sources studied in detail in the community, standard hydro- logic and hydraulic study methods were used to determine the flood hazard data required for this study. Floods having recurrence intervals of 10, 50, 100, and 500 years have been selected as having special significance for flood plain management and for flood insurance premium rates. The analyses reported here reflect current conditions in the watersheds of the streams. 3.1 Hydrologic Analyses Hydrologic analyses were carried out to establish the peak discharge- frequency relationships for floods of the selected recurrence inter- vals for the stream studied in detail in the community. The section of Kiowa Creek studied was ungaged. Discharges were determined for Kiowa Creek using the section of the u.s. Geological Survey Technical Manual No. 1 dealing with ungaged streams (Refer- ence 6). The basin parameters. needed to utilize this method, drain- age area and basin slope, were measured from u.s. Geological Survey topographic maps at a'scale of 1:250,000, with a contour interval of 200 feet (Reference 7). Peak discharges were determined for the 10- and lOO-year floods and plotted on log-probability paper. A straight line was drawn between these points to get the 50-year discharge, and this line was extrapolated to get the SOO-year discharge. Peak discharge-drainage area relationships for Kiowa Creek are shown in Table 1. Table 1. Summary of Discharges Flooding Source and Location Drainage Area (Square Miles) Peak Discharges (Cubic Feet per Second) 10-Year 50-Year 100-Year SOD-Year Kiowa Creek At Interstate 76 709.2 14,237 36,000 49,346 96,000 3.2 Hydraulic Analyses Analyses of the hydraulic characteristics of the stream in the com- munity were carried out to provide estimates of the elevations of floods of the selected recurrence intervals along the stream studied in detail.