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• • • • • • • • • • • • • • 14 Flaming Gorge Spill May July 700 k r- ENo)Action 600 k 5001, --- 400 k c s 300 k s 200 k -- --- -- --- -- --- - -- 100 k 0 ---- L -- - 0% 101; 4 0 60% 80% 10014 Yerceltta_e Excecdance Reach One August through February Base Flow Release Results Releases made from August 1" through the end of February are referred to as the baseflows in Reach One. Figure 15 shows the distributions of baseflows that occurred for Reach One in the model as a result of operating under the Action and No Action alternatives. For reference to how Flaming Gorge Dam was operated prior to 1992, the distribution of actual base flows in Reach One that occurred from 1971 though 1991 are included in the figure. The distribution of unregulated inflows to Flaming Gorge Dam during this same period is also included. The unregulated inflows, in comparison to the actual base flows, indicate the effects of reservoir regulation at both Fontenelle Darn and Flaming Gorge Dam on Reach One flows during this period. Under the No Action alternative, releases during the months of November through February are only restricted to be less than power plant capacity and greater than 800 cfs. The Action alternative maintains much stricter control of the releases during this period. This difference is evident in Figure 15 between 0 and 20% exceedance. In many cases, the No Action alternative strictly controls releases from August through October only to have releases increase dramatically in November when these controls are no longer valid. A good example of this situation is shown in Figure 4. Releases during November for all three of these wet years were nearly double the releases that occurred during the preceding October. Figure 15 Exceedance Percentage Flows for Reach One Flows During Base Flow Period