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I . I I I '. I I I I I I I I I I . I I nodes, reservoir elements which make up the computer UDSWMM hydrology model are all located on these maps, with appropriate delineation of their linkage and general routes of flow. The hydrology models for the 10-, 50-, 100- and 500-year events are presented in appendices A 1 through A4 under the identifiers: sbc_l On.out (1 O-year), sbc_50n.out (50-year), sbc_ln.out (100-year), and sbc_5n.out (500-year). All input and output data is presented in the files, however complete hydrographs are not printed to save paper. For those interested, electronic input files can be provided, and the user can obtain the desired hydrographs. Selected hydrographs are presented in Section V. SUMMARY FLOW RESULTS AND COMPARISON Peak flows are presented at many key points on the drawings. Table 1-1 is a summary comparison of the previous USACE hydrology model, the figures used in the current effective floodplain maps, and the draft figures for this modeling effort, The summary table begins at Gross Reservoir and works downstream. At Highway 93 the flood flows split along two or more roughly parallel locations down the floodplain. Stream or node element numbers are given in the table, which can be identified on the drawings. At the lower end, the flows leave the watershed at three distinct locations. The main flow in South Boulder Creek joins with Boulder Creek at the historic confluence. On the west side of 55th downstream of Arapahoe, much of the West Valley area appears to flow through an industrial/commercial area directly to Boulder Creek. Also, flow leaving South Boulder Creek just downstream of Arapahoe through overflowing to Valmont will partially fill Valmont or overflow to Boulder Creek. 1-9