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A 'minimum hydrograph' which maintains a sediment equilibrium may be defined for a number of conditions, including the historical period of record, the historical record adjusted to reflect existing conditions in the basin (baseline), and also with water development projects imposed upon the baseline condition. However, a sediment transport equilibrium may Still be maintained at a higher or lower rate, with differing hydraulic characteristics such as width, depth, velocity, roughness, slope, and channel pattern, so this criteria is not a panacea in preventing channel adjustments which may have adverse impacts upon fish habitat. Andrews' (1986) analysis of suspended sediment transport before and after the construction of Flaming Gorge indicates that the Green River from the mouth of the Yampa to the mouth of the Duchesne River is in equilibrium, although the mean annual suspended sedimen load decreased by 54% from 6.92 to 3.21 million tons. The difficult part islin determining what ? an acceptable decrease in sediment transport is, while sti 1 maintaining a quasi-equilibrium condition. The Deerlodge Park alluvial reach of the Yampa River is probably the most responsive area to changes in the water and sediment load and its distribution throughout the year. This is due to the relatively low gradient upstream of the Yampa Canyon and its location below the confluence of the Little Snake River which is delivering the majority of the total sediment load. The Yampa Canyon and spawning areas are not alluvial reaches, but if channel adjustments can be minimized in the Deerlodge Park reach, simultaneous changes elsewhere will be minimized. Possible changes within the Yampa Canyon and spawning areas resulting from changed water and sediment deliveries would most likely affect the storage of sediment in backwater areas, bars, pools, and other localized areas. Reductions in total load may also affect the Green River channel morphology. (As listed previously, there have been a number of sediment budgets preformed in 'different locations, involving different assumptions and using either suspended ,load or total load data. Elliott's total sediment load budget for the Deerlodge Park reach utilized percentage reductions in flow duration curves and In the sediment supply to investigate changes specifically at Deerlodge Park. I think it is a valid assumption that the load leaving this reach and entering the canyon represents the supply available to the spawning reaches within the canyon. c O'Brien's annual budget (1987) used the sum of the Little Snake near Lily and the Yampa River near Maybell suspended sediment values as the supply available at Deerlodge Park. However, a suspended sediment relation was defined for Deerlodge Park by the US Geological Survey (Elliott, et al.) and this seems more appropriate to use because the assumption that tributary sediment is delivered to Deerlodge Park without storage may not be valid. Further downstream of Deerlodge Park the gradient is steeper so storage of significant volumes are precluded. Also, total sediment load and bedload curves are available at Deerlodge Park and Mathers Hole. These are more appropriate to use than suspended sediment curves, since the bedload size fractions have more impact on spawning habitat than suspended sizes. For these reasons, a total sediment budget was constructed. Bedload curves may also be used within the sediment budget.