Laserfiche WebLink
Figure 2. Flooding Looking East at State Highway 52, 1973 <br />3.0 ENGINEERING METHODS <br />For flooding sources studied in detail in the community, standard hydro- <br />logic and hydraulic study methods were used to determine the flood <br />hazard data required for this study. Floods having recurrence intervalq <br />of 10, 50, 100, and 500 years have been selected as having special sig- <br />nificance for flood plain management and for flood insurance premium <br />rates. The analyses reported here reflect current conditions in the <br />watersheds of the flooding sources. <br />3.1 Hydraulic Analyses <br />Hydrologic analyses were carried out to establish the peak discharge- <br />frequency relationships for floods of the selected recurrence inter- <br />vals for each stream studied in detail in the community. <br />The U.S. Army Corps of Engineers computed and provided peak discharges <br />for the 10-, 50-, 100-, and 500-year floods on.the South Platte <br />River, .which .were utilized for this Flood Insurance Study (Reference <br />5). Generally, data were taken from several gages located in <br />surrounding areas and were analyzed statistically using the log- <br />Pearson Type III method (Reference 6). This information was then <br />routed to the study area. <br />Peak discharge-drainage area relationships for the South Platte <br />River are shown in Table 1. <br />4