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would be located upstream of the tributary confluences with the mainstem river. Water depletion attributed to the High Savery project would however decrease the sediment transport capacity in the reach from Dixon to Lily. This would result in aggradation of this reach until a balance was struck between tributary sediment loading and sediment transported out of the reach to the Yampa River. Once a new equilibrium condition is reached, the mean annual sediment load to the Yampa River should approach pre-project levels. Butler assumed that the Little Snake River is currently adjusting to existing depletions by aggrading the channel. Recent channel cross section surveys do not show evidence of an aggrading stream bed (FLO Engineering 1994b). Based on the analysis of sediment sizes transported at the Jensen and Lily gages, Butler (1988a) estimated that the Little Snake River has averaged 548,000 tons/yr of sand-sized sediment (53% of the Green River Jensen gage sand load). This estimate would be much greater if the bias correction factor for the rating curve is applied. He concluded that the depletions from the Sandstone project would impact the Green River over the long term and that combined with depletions from the Yampa River would adversely impact habitats utilized by endangered fish. Butler (' 988b) attempted to I pull together' a number of basin wide and site specific investigations of the Yampa River involving sediment transport measurements and sediment budget analyses. He indicated that various mathematical modeling efforts should be viewed in terms of trends, not in terms of absolutes. It was emphasized that if any of the physical processes of the prevailing river system were stressed too greatly then the sediment rating curves which define the sediment budget may become invalid. This is a valuable observation and it should be noted that the sediment rating curves for the 38