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sediment transport characteristics of the Little Snake, Yampa and Green rivers. The proposed Sandstone Reservoir would not trap significant quantities of sediment because of its relatively small reservoir storage pool (52,000 af) and its location upstream of major sediment producing tributaries. But Sandstone Reservoir would decrease river discharge approximately 32,000 af per year (about 8% of the annual flow). High Savery Dam is predicted to trap about 1.5% of the sediment previously delivered to the Yampa River and the reservoir will deplete an estimated 12,000 af per year or about 3% of the annual yield of the Little Snake River (Burns and Mc Donnell 1999). Butler (1988a) applied previously derived, uncorrected sediment rating curves from Andrews (1980) and Elliott et al. (1984) to assess changes in Little Snake sediment load. Historical baseline data (with existing depletions) and project operation data were analyzed for 1930 through 1982. A decrease in sediment load in the Little Snake River of 32% (157,900 tons/yr) was predicted using the proposed Sandstone project flow duration curves and monthly project operation schedules. He also estimated a decrease of 18% in the effective discharge. Wyoming's Biological Assessment estimated a 14.7% potential decrease in suspended sediment load at the Lily Gage based on mean monthly flows for the same project period (Butler 1988a). Without the bias correction factor for the sediment rating curves the sediment load at the Lily Gage is underestimated by 40%. The potential effects of water depletion on the sediment load may be understated in Butler's analysis. The prediction by Butler (1988a) that the proposed Sandstone project would reduce the sand load of the Little Snake River by one-third of the historic yield requires some clarification, especially with its implication for the effects of the High Savery project. High Savery Reservoir would not affect sediment delivery to the Little Snake River from the four high sediment yielding tributaries because it 37