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I I I I g. Flood Hazard Factors The flood hazard factor is defined as the weighted distance, in feet, between the 10-year and 100-year frequency water surface elevations, throughout a reach. The distance was determined from the plotted water surface profiles. Values were rounded to the closest one-tenth of a foot, h. Floodway Depth-Width Analysis I I I Data for the depth-width analysis were developed at representative cross sections in each reach. Increased depths of 0.5 foot, 1.0 foot, and 2.0 feet were added to the elevation of the present 100-year flood, and the remaining floodway widths needed to contain the 100- year discharge were determined, The increased depth-width values determined are presented by graphs and a tabulation (see Exhibits D and E). i. Cross Section Location Map I The location, orientation, and width of the representative cross sections analyzed for floodway depth-width relationships are shown on Exhibits G-l and G-2. I I j. Flood Zone Maps I I I The maps, Exhibits 01 and 02, show the delineated flood zones, Map source for this exhibit is the recent (August, 1971) Louisville Urban Area and Topographic Map prepared by Kenneth L, Bruns & Associates, Inc" Longmont, Colorado, Permission to use this map source for flood insurance studies and reports was granted by the City of Louisville. I I I I I II The approximate areas inundated by the 100-year frequency flood are identified as Zone A, Zone B, the area above Zone A inundated by the SOD-year frequency flood, is included in Zone A because of its close proximity to the 100-year flood line, Zone C is the area above the SOD-year flood line. The delineated flood hazard zone boundaries and the base flood elevation lines (lOO-year frequency flood) are shown on the flood zone maps. Data on File The survey, hydrologic, hydraulic, and other pertinent backup data and computations are on file with the Soil Conservation Service, USDA, 2490 West 26th Avenue, Denver, Colorado 80211, 3