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<br />Draft Fmal Completion Report to UDWR for Contract #93-1070, Amendment 3 <br /> <br />30 <br /> <br />Table 5. Geomorphic coding of nursery habitat used in interpreted video GIS. <br /> <br />Code Description <br /> <br />bsd the downstream end of a secondary channel associated with a bank-attached bar <br />bsu the upstream end of a secondary channel associated with a bank-attached bar <br />bsb a superimposed bar found along a bank-attached bar margin <br />bds stranded dunes on a bank-attached bar margin <br />bsc chute channel across a bank-attached bar <br /> <br />ip isolated pool on a bank-attached bar <br />mcb mid-channel bar <br /> <br />hsv horseshoe vortex <br /> <br />oth other <br /> <br />Flow and Sediment Transport Modeling <br /> <br />Details of Andrews and Nelson (1989) Flow and <br />Sediment Model Formnlation <br /> <br />Initial cross-section topography was used as input to the model, and the topography was smoothed and sp1ined <br /> <br />to a 41x13 matrix. The smoothed topography was then used to calculate the channel topography in the sloped <br /> <br />coordinate system of the reach-averaged energy gradient; the elevation of the bed was given in depth below the water <br /> <br />surface. The reformulated topography, discharge, and roughness was then used in the calculation of the vertically- <br /> <br />averaged integrated velocities in order to determine shear stress. These velocities were then used for the calculation of <br /> <br />discharge at each point in the matrix and the centerline water slope such that the same amount of water flowed out of the <br /> <br />reach as flowed into the reach. <br /> <br />In the sand-bedded Green River, Andrews and Nelson (1989) used a roughness coefficient that included all <br /> <br />forms of roughness such as grain.' bed form, and bar form roughness, and was scaled with flow depth. This approach <br /> <br />was used for cases where bedform geometries were unknown and was valid when sediment transport rates were similar <br /> <br />over much of the bed (Andrews and Nelson. 1989). The value of this coefficient was adjusted until the observed water <br /> <br />surface slope for the reach was achieved. The error associated with using one roughness parameter to describe the <br /> <br />whole channel'affected the spatial distribution of roughness within the channel rather than total roughness of the whole <br />