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report (Elliott et al. 1984) did not address the potential effects of flow or sediment reductions in the individual rivers. Andrews (1986) reviewed the historical sediment load data in the Green and Yampa rivers to determine the effects of Flaming Gorge Reservoir on the Green River downstream of the Yampa River confluence. He noted that the reservoir did not significantly affect the mean annual runoff but that the duration of large discharges that transported most of the sediment had been severely curtailed. At the Jensen and Green River, Utah gages the sediment load had decreased by 54% and 48% respectively. Andrews stated that the channel morphology quasi- equilibrium that was apparent prior to Flaming Gorge construction no longer existed. He concluded that although a balance between the sediment supply and sediment transport capacity had been attained in the reach from the mouth of the Yampa River to the Duchesne River confluence, an adjustment of the channel morphology downstream of the Jensen gage was incomplete in 1978. He indicated that perhaps 30 years would be required to attain an expected value of the channel width based on post-reservoir effective discharges. The channel width was estimated to have decreased by 13% in his study reaches. Andrews r analysis of the Jensen and Ouray gage sediment loads indicated that an average of 2.4 million tons/yr have been deposited and he concluded that substantial aggradation had occurred in this reach since the construction of Flaming Gorge Dam. He surmised that the aggradation may be concentrated within a short distance upstream of the Ouray gage. Based on recent channel surveys; however, it appears that the Ouray Wildlife Refuge reach has been subjected to some channel degradation related to changes in the width to depth ratio (FLO 1986; FLO 1996). This was verified through review of 1963 aerial photos. 34