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Estimates of channel and overbank roughness coefficients were made ateer tleld lnvestlgatLOn at tne study areas. Mannlng's "n'. values ranged from 0.015 to 0.040 in the channel and from 0.035 to 0.120 in the overbank areas. Starting water-surface elevations for Harvard Gulch and West Harvard Gulch were obtained at control sections.. The controL on Harvard Gulch.was a broadcrested weirflow section over South Logan Street, and on West Harvard Gulch, a broadcrested weir section over West South Platte River Drive. Starting water-surface elevations for Harvard Gulch Overflow were taken from the Harvard Gulch profile. For Dry Gulch (Harvard Gulch Tributary). the starting water-surface elevations were also taken from the Harvard Gulch profile because these streams are likely to peak at close to the same time.. Areas of shallow flooding along West Harvard Gulch and Dry Gulch (Harvard Gulch Tributary) were determined using normal-depth calculations. Shallow flooding along Harvard Gulch was determined using normal-depth calculations and a network analysis of floodflows and depths along roads. Goldsmith Gulch and Southmoor'Pa~k Tributarv Cross section data, Manning's fin" values, and starting water- surface elevations were developed for use in the 1976 UDFCD Flood Hazard Area Delineation report for Goldsmith Gulch and its tributaries (Reference 15). Cross section information was obtained from topographic maps (Reference 56). Typical Manning's "n" values for Goldsmith Gulch and Southmoor Park Tributary ranged from 0.030 to 0.045 in the channel, and from 0.035 to 0.055 in the overbank areas. Starting water-surface elevations for Southmoor Park Tributary were taken from the Goldsmith Gulch profiles. Starting water-surface elevations for Goldsmith Gulch were determined using a rating curve. Additional cross sections, added at a berm along Goldsmith Gulch near the confluence with Cherry Creek, were taken from Cherry Creek improvement plans (Reference 51). Addi tional cross sect ion data from improvement plans were included along Goldsmith Gulch and Southmoor Park Tributary for the more recent construction of Eastman Avenue. Sanderson Gulch Cross section data on Sanderson Gulch used in the hydraulic analyses were taken from construction drawings, as-built construction drawings, field surveys, and topographic mapping (Reference 57). The starting water-surface elevations were computed usi~g the West South Platte River Drive crossing as a control. Roughness coefficients were estimated after field investigation and ranged from 0.015 to 0.060 in the channel and from 0.035 to 0.100 in the overbank areas. 23