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<br />Starting WSELs for Harvard Gulch and West Harvard Gulch were obtained at control <br />sections. The control on Harvard Gulch was a broadcrested weirflow section over <br />South Logan Street, and on West Harvard Gulch, a broadcrested weir section over <br />West South Platte River Drive. Starting WSELs for Harvard Gulch Overflow were <br />taken from the Harvard Gulch profile. For Dry Gulch (Harvard Gulch Tributary), the <br />starting WSELs were also taken from the Harvard Gulch profile because these <br />streams are likely to peak at close to the same time. <br /> <br />Areas of shallow flooding along West Harvard Gulch and Dry Gulch (Harvard Gulch <br />Tributary) were determined using normal-depth calculations. Shallow flooding along <br />Harvard Gulch was determined using normal-depth calculations and a network <br />analysis of floodflows and depths along roads. <br /> <br />Goldsmith Gulch and Southmoor Park Tributary <br /> <br />Cross-section data, Manning's "n" values, and starting water- surface elevations were <br />developed for use in the 1976 UDFCD Flood Hazard Area Delineation report for <br />Goldsmith Gulch and its tributaries (Reference 15). Cross-section information was <br />obtained from topographic maps (Reference 56). Typical Manning's "n" values for <br />Goldsmith Gulch and Southmoor Park Tributary ranged from 0.030 to 0.045 in the <br />channel, and from 0.035 to 0.055 in the overbank areas. Starting WSELs for <br />Southmoor Park Tributary were taken from the Goldsmith Gulch profiles. Starting <br />WSELs for Goldsmith Gulch were determined using a rating curve. <br /> <br />Additional cross sections, added at a berm along Goldsmith Gulch near the <br />confluence with Cherry Creek, were taken from Cherry Creek improvement plans <br />(Reference. 51). Additional cross-section data from improvement plans were <br />included along Goldsmith Gulch and Southmoor Park l"ributary for the more recent <br />construction of Eastman Avenue. <br /> <br />Sanderson Gulch <br /> <br />Cross-section data on Sanderson Gulch used in the hydraulic analyses were taken <br />from construction drawings, as-built construction drawings, field surveys, and <br />topographic mapping (Reference 57). The starting WSELs were computed using the <br />West South Platte River Drive crossing as a control. Roughness coefficients were <br />estimated after field investigation and ranged from 0.015 to 0.060 in the channel and <br />from 0.035 to 0.100 in the overbank areas. <br /> <br />At Lipan Street along Sanderson Gulch, flows escape along the left .overbank and <br />extend to the South Platte River as shallow flooding. These shallow flooding areas <br />were determined using normal-depth calculations. <br /> <br />A portion of flooding on Sanderson Gulch from South Sheridan Boulevard <br />(State Highway 95) downstream to Cross Section BQ has been labeled with a Profile <br />Base Line. Flooding backs up at the culvert under South Sheridan Boulevard and <br />flows over the road at a low spot just-north of the culvert. <br /> <br />22 <br />