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<br /> FLOODPLAIN REPORT - Tyra Tract D and Sawmill Gulch, Breckenridge, Colorado <br />e WWE did not continue beyond the eastern limit of the Tract D property. The Town of <br /> Breckenridge Engineering Department (Eric Guth and Tom Daugherty) and the FEMA Regional <br /> Hydrologist (John Liou) concurred with our mapping limits. <br /> The overflow flooding from Cross-Sections No. 58 to No. 55 in Sawmill Gulch flow eastward <br /> for a short distance before turning northward and following a natural swalelhistoric flow path <br /> through the central portion of Tyra Tract D. This is in the area where the proposed building will <br /> be built. The area currently has no defined channel and the flooding condition is essentially <br /> shallow, widespread flow through an area currently vegetated with willows. <br /> The conclusion of the split flow analysis is that significant flow leaves the main channel of <br /> Sawmill Gulch. Thus, the peak flow rate of Sawmill Gulch reduces in the downstream direction <br /> as a result of the overbank outflows. This is reflected in Table I, showing Sawmill Gulch peak <br /> flow rates "stepped downward" from 248 cfs at the upstream limit of Tyra Tract D to 180 cfs, at <br /> approximately the central portion of Tract D, to 130 cfs at the Four O'Clock Road culvert. The <br />e split flow amounts flow to the east out of the channel and then turn north until reaching Four <br /> O'Clock Road where they are redirected to the east. <br /> Table 1 <br /> Sawmill Gulch Flow and Profile Data <br /> SECTION FLOW IN CFS WATER SURFACE ELEVATION" <br /> eu Ivert 130 9716.0 <br /> 52.1 130 9716.0 <br /> 52.2 180 9716.6 <br /> 53.1 180 9717.6 <br /> 54.0 180 9719.6 <br /> 55.0 180 9724.0 <br /> 56.0 212 9726.6 <br /> 57.0 212 9731.4 <br /> 58.0 248 9735.2 <br /> 59.0 248 9739.6 <br /> 59.1 248 9742.4 <br />e . Datum is NGVD 1929. <br /> 971-055.010 Wright Water Enginee~, Inc. Page 11 <br />