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On Van Bibber Creek, the flows were based on basin development conditions as of 1984. It should be noted that a relatively minor difference exists between future and existing flows on this creek. This is because of the fact that much of the basin is already developed. On Leyden Creek, the flows were based upon future basin development conditions without Leyden Lake in place. Since the flows for the 50- and 500-year events were not reported in the Major Drainageway Planning Report, it was necessary to interpolate and extrapolate these flows from the known flows at various design points. The extrapolation and interpolation of these events were performed using a log-normal probability relationship. The City of Edgewater is immediately west of Sloans Lake. The area between Sheridan Boulevard and Depew Street has a major drainageway resulting from a 2.07 -square-mile tributary drainage basin flowing 3.4 miles easterly through it. The total basin area, including the 2.07-square-mile area, is 5.48 square miles. There is a stormwater channel from Ingalls Street and 20th Avenue to Depew Street. Peak discharges of 1,070 cfs for the 25-year flood were originally used to check "as-built" design conditions for the drainageway between Depew Street and Sheridan Boulevard. This flow revealed similarities and differences between past and present conditions in the area (Reference 50). The regulatory IOO-year discharge was applied to establish floodplain delineations. Findings indicate the I DO-year flood is contained within the improved channel between Depew Street and Sheridan Boulevard, and hydrographs of various frequencies have been generalized at this point. The flood discharge values used for Lena, Jackson, and Apex Gulches within the City of Golden were obtained from the 1975 study done for the UDFCD by Wright-McLaughlin Engineers (Reference 47). In this study, the CUHP was used to calculate the 10-, 25-, and 100-year discharges for present and future development conditions. The design rainfall used in the study was supplied by the UDFCD based on information from the NOAA Report (Reference 46). During the study, the drainage area of Lena Gulch was field checked to determine that 1982 development conditions would be properly reflected by the estimated future development conditions reported in the 1975 UDFCD study. The future development conditions for flood discharge values from the 1975 UDFCD study were determined to be valid for the study. The 50- and SOD-year discharges were estimated from the frequency curves based on the 10-, 25-, and 100-year discharge values. Peak discharges of the selected recurrence intervals within the Town of Morrison were calculated for Bear Creek using a log-Pearson Type ill frequency analysis (Reference 41). Frequency analyses were calculated using streamflow data from USGS stream gaging station located at the western edge of Morrison (Gage No. 067105 with continuous records since 1922), and historical records for the flood of 1896. As with other streams in Jefferson County, it was necessary to analyze rain and snowmelt events separately to define the flood-frequency curve at the above referenced gage site. The results of this stream gage analysis were used as the discharges for the reach of Bear Creek upstream of the confluence with Mount Vernon Creek. The reach of Bear Creek downstream of the confluence with Mount Vemon Creek required adjustment of the gage records because of the intervening drainage area. For this reach and others along Bear Creek, regression equations, including only significant independent variables for the mean coefficient of variation (and hence the standard deviation), and skew for each type of event, were used to compute the flood-frequency curve at any ungaged site with given drainage area and mean watershed elevation. 28