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reaches 6936.1 feet. The change in storage volume between this elevation and the elevation of the first row <br />• of perforations in the riser pipe is 160.2 - 131.8 = 28.4 AF. Table 2 shows the adjustments to the computed <br />• <br />stage-discharge relationship. <br />Results of the hydrologic routings of the 10~year and 100-year 24-hour duration runoff hydrographs <br />are included in the Appendix. The 100-year peak outflow equals 717 cfs with a corresponding peak water <br />surface elevation in the pond of 6940.6 feet. For the 10-year event, the maximum discharge is 12 cfs with <br />a computed water surface elevation of 6938.1 feet. <br />Pond D <br />The drainage area for Pond D appears to have changed significantly since the original pond <br />certifications and designs were developed. The drainage area delineated on the enclosed map equals 916 <br />acres. The runoff volume and peak runoff corresponding to this acreage were obtained from tfie charts <br />contained in Peak Flows in Colorado. For an average curve number of 79, the runoff volume and peak <br />discharges are as follows: <br />Event 8 Duration Runoff Volume (AF) Peak Inflow (cfs) <br />10-year, 24-hour 30 163 <br />100-year, 24-hour 74 448 <br />Rating curves for the riser pipe and spillway were developed using the same procedure as described <br />for Pond A. Tables 3 and 4 show the results of these computations. <br />Hydrologic routing of the inflow hydrographs indicates a 100-year peak outflow from Pond D of 285 <br />cts with a maximum water surface elevation in the pond of 6651.9 feet. Similarly, the 10-year outflow is 11 <br />cfs, with a maximum stage of 6850.3 feet. <br />Pond G <br />Hydrologic analysis of the Pond G watershed yielded the following runoff volume and peak <br />• <br />discharge data corresponding to an average curve number of 79: <br />5 <br />Water Engineering & Technology, Inc. <br />