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• DRAFT FeMvary25, 1998 3. The bed at the Greendale gauge aggraded 0. 3 ft between 1961 and 1987. 4. The bed at the Jensen gauge has not changed in elevation since 1948. Speculation about channel degradation in the Razorback bar and Escalante Bottoms area is not supported by these findings. 5. Degradation of about 0.3 ft of the channel bed at Ouray occurred between 1951 and 1966. It is unlikely that these changes are related to Flaming Gorge Dam. 6. Prior to closure of Flaming Gorge Dam, the Green River near Greendale, UT, was covered by ice between 3 and 5 months per year. The last year that ice cover was reported at this gage was 1958. 7. Between the winters of 1946-47 and 1960-67, the average duration of ice cover was 3.6 months near Jensen. Since that time, the duration has decreased to 0.8 months. At Ouray, the average duration of ice cover was 3 months between 1951 and 1965. 8. A new floodplain, in apparent equilibrium with reduced floods has developed in the • Uinta Basin, especially in the Ouray National Wildlife Refuge. This floodplain is regularly inundated but the area extent of these surfaces is an order of magnitude less than the pre- dam floodplain. It appears that significant inundation of the alluvial valley of the Green River may not have regularly occurred since the 1920's. 9. Significant channel narrowing in Lodore Canyon has occurred since closure of Flaming Gorge Dam. Numerous eddy bars have been vegetated and backwater habitats may have been lost. Schmidt, J.C. 19%. Geomorphic control of the distribution of age-0 Colorado Squawfish in the Green River in Colorado and Utah. Draft Manuscript, Department of Geography and Earth Resources, Utah State University, Logan, Utah. 28p. Regional geology controls the geomorphic organization of the Green River in Colorado and Utah and produces a series of river segments that are either restricted meanders, fixed meanders, or canyons with abundant debris fans. The distribution of channel planform controls the distribution of shoreline complexity, and there is no systematic downstream change in channel planform or in shoreline complexity. Backwater habitats, which typically are abundant where complexity is high, are used as nursery areas by age-0 Colorado squawfish. Field measurements of channel and bar topography, air photo and geographic information system analysis, and simulation • modeling show that the location of critical nursery habitat segments of the river is 26