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I I I I I I I I I I I I I I I I I I I 61 which show that there was significant transport of bed material in 1993, but very little in 1994. The upstream entrance of flow to the three side channel field sites are composed primarily of gravel, and showed very little change throughout both years. Fine sediment was deposited near the banks in 1993, but overall changes to the main entrance of flow were small. Mid-sections of the side channel sites generally showed some scouring of fine sediment from the thalweg, and the deposition of fine sediment on the banks in 1993, but there were not substantial changes during the 1994 season. The net result was generally a deeper and narrower channel from 1993 runoff and some filling with sediments during 1994. The downstream end of these sites control fish access into the backwater at moderate or low flows. These areas showed scouring with the entrance to the backwater becoming deeper in 1993, unless vegetation stabilized the substrate. In 1994 this area showed a small amount of re-filling with sediment at site 2, and significant filling at site 3. Site 1 showed very little change throughout both seasons due to lower water velocities and vegetation. In general, the flows of 1993 caused channel change at our sites where there was predominantly silt and sand, but the morphology of gravel areas did not change significantly. Vegetation clearly stabilized sediments, and was abraded but not uprooted in 1993. The 1994 flows were relatively small which resulted in deposition of fine sediment in some areas. Evaluatiol,1. of Coarse-Sediment Transport Habitats for endangered fish in the upper Colorado River are formed by coarse sediment that moves only at discharges well in excess of the mean annual flow. An analysis of the relation between shear stress and discharge at four sites in the Grand Valley indicate that the bed material is at the threshold for motion at a discharge of 300 ems (10,600 cfs) above the confluence of the