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the other year, flow control restrictions at Delta limited releases. The reason the FWS demand hydrograph was met more often than the recommended flows at the Whitewater gage was that the predicted magnitude and timing of tributary peaks did not match the actual magnitude and timing of tributary peaks. Improving the accuracy of predicting the magnitude and timing of tributary peaks would increase the frequency recommended flows would be met. While recommended peaks were not consistently met, flows under Model Runs B, C, and D would improve habitat conditions for the endangered fish because the frequency of these spring peaks would Increase. Base Flows The flow recommendations include minimum base flow levels for non-peak flow periods. As is the case for peak flows, these desired base flow levels are dependent on hydrologic conditions for the Whitewater gage. Recommended base flows for the non-peak period (June through the following April) range from 750 to 1,050 cfs in dry and moderately dry years; 1,050 cfs (2,000 cfs maximum) in average dry and average wet years; and 1,500 cfs (2,500 cfs maximum) in moderately wet and wet years. The modeled alternatives do not modify Aspinall Unit daily releases from the values set by the FWS demand hydro graph if actual tributaries differ from those forecasted. Time constraints prevented a refinement of model rules that further accommodate changes affecting base flows. Model results show that under baseline conditions (Run A), base flows at the Whitewater gage exceed 95 percent of recommended flows approximately 91 percent of the time, and exceed 80 percent of desired flows approximately 96 percent of the time. Under the flow recommendation alternatives (Runs B, C and D), base flows at the Whitewater gage exceed 95 percent of the recommended flows 97 percent of the time, and 80 percent of the recommended flows 99 percent of the time. For modeling purposes, it was assumed that the 750 cfs base flow level at Whitewater for specified months in dry and moderately dry years is the minimum flow during these periods. As such, the model made releases to maintain the 750 cfs flow level in these periods. Drier years typically required additional releases which resulted in an increased draw on Blue Mesa storage. The provision ofa minimum 750 cfs base flow at the Whitewater gage provides more water to the'Redlands Diversion Dam than under baseline (Run A) in dry years. The Redlands Diversion users have water rights totaling 850 cfs, although the physical capacity is about 820 cfs. The Federal Energy Regulatory Commission exemption under which the diversion operates, limits diversions to 750 cfs if the flow below the diversion falls below 300 cfs. Fish passage flows Fish passage flows equal or greater than 300 cfs are desired below the Redlands Diversion when recommended flows at the Whitewater gage equal or exceed 1,050 cfs (Under conditions where recommended base flows are less than 1,050 cfs, flows less than 300 cfs below Redlands are acceptable). A fish ladder allows native fish to move upstream past the dam. Flow recommendations 5