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30 <br />in the upstream and downstream directions to minimize the effect of inflow and outflow <br />boundary conditions that were supplied to the model as a uniformly distributed inflow <br />discharge and either a fixed downstream elevation or a function of discharge per unit <br />depth. Hydraulic models were calibrated by comparing observed and predicted water <br />surface elevations for measured flow conditions. Depths calculated from predicted water <br />surface elevations were generally within 3-5% of measured depths and predicted <br />velocities were typically within 5-10% of ADCP measured values. <br />A range of flows bracketing the discharges observed during the study at each site <br />were simulated. For the Green River site, simulations were run for discharges of 50 m3/s, <br />50-750 m3/s in increments of 50 m3/s, and 1100 m3/s. Flows of 6, 30, 50, 100, 150, 250, <br />300, 350, 400, 500, 750, and 900 m3/s were simulated for the Yampa River site. The <br />highest discharge simulated at each site corresponds closely to the peak flow of record <br />measured during 1984. <br />Stream power map development <br />Maps depicting an approximation of stream power (calculated as depth times <br />mean column velocity) for the range of discharges above were generated to provide a <br />simple evaluation of the potential for sediment transport at different discharges. Because <br />this measure of stream power alone is not useful for making quantitative predictions of <br />sediment transport, comparisons of stream power maps for different flows combined with <br />observed changes in channel geometry at cross sections were used to evaluate the ability <br />of stream power to predict potential sediment movement.