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Peak discharge-drainage area relationships for Fountain, Jimmy Camp, Security, and Widefield Creeks are shown in Table 1. 3.2 Hydr aulic Analyses Analyses of the hydraulic characteristics of flooding from the sourceS studied were carried out to provide estimates of the eleva- tions of floods of the selected recurrence intervals. Water-surface elevations of floods of the selected recurrence intervals were computed through use of the COE HEC-2 water-surface profile computer program (Reference ]0). Fountain Creek crf.i';:S sect. inns were obtained from maps compiled by Bohannon '1llc1 Huston, Inc., in 1972 (Reference 11). Cross sections for Jimmy Camp Creek were compiled from 1973 SCS aerial photography (Reference 12), Cross sections for Security and Widefield Creeks Were compiled from aerial topographic mapping prepared for the COE by VTN, Inc., in 1976 (Reference 13). Location" of ';elected cross sections used in the hydraulic analyses are shown on the Flood Profiles (Exhibit 1). For stream segments for which a floodway was computed (Section 4.2), selected cross section locations are also shown on the Flood Boundary and Floodway Map (Exhibit 2). Channel roughne5s factc>rs (Manning's "n") used in the hydraulic computations Were chosen by using engineering judgment and based on field observations of the streams and flood plains. Channel roughness values for the streams ranged from 0.015 to 0.040, with overbank values ranged from 0,020 to 0.080. Starting water-surface elevations were based on either coincident condition elevations or critical-depth computations. The hydraulic analyseS for this study Were based on the assumption that limited clogging of stream channels will occur and that all bridges and flood-control structureS would remain intact, The flood elevations shown on the profiles are thus considered valid if hydraulic structures remain intact with little blockage, operate properly, and do not fail, . All elevations are referenced to the National Geodetic Vertical Datum of 1929 (NGVD). Elevation reference marks used in this study are shown on the maps. . 4.0 FLOOD PLAIN MANAGEMENT APPLICATIONS The NFIP encourages State and local governments to adopt sound flood plain management programs. Therefore, each Flood Insurance Study produces 6