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• • • • • • • • 9 shown in Figure 6. These reservoir- elevations are those that were exceeded by 50% of the 65 potential reservoir elevations that occurred for each month. In the dryer scenarios, reservoir elevations are typically much lower than in the average or wet scenarios. Figure 7 shows reservoir elevations that were exceeded by 90% of the potential reservoir elevations that occurred for each month. Figure 7 is significant because it shows a tremendous improvement for Action alternative in comparison to what was reported in the October report. Now, the Action alternative yields reservoir elevations that are even higher than those yielded by the No Action alternative. The October report showed a large disparity between the Action and No Action alternatives with the Action alternative much lower than the No Action alternative. The model results indicate that reservoir elevations are basically stable throughout the model run under both alternatives. That is to say the reservoir elevation did not gradually increase or decrease under the Action and No Action alternatives in the later years of the run. For this reason, it was valid to combine all of the reservoir elevations into a single dataset, grouped by month and then ranked from lowest to highest into monthly distributions. Figures 8 and 9 show these distributions for the months of February and June. These months are shown because reservoir elevations are typically near their lowest level of the year by the end of February and near their highest level by the end of June. Both figures show that the distributions Fi ure 8 February Reservoir Elevation Distribution Plot Flaming Gorge End of February Elevations Modelled vs. Historic 6045 - - - 6045 6040 6040 6035 6035 6030 6030 6025 6025 ° c 6020 0 - 6020 60 l 5 d 6015 W W N 6010 u U 6010 U 6005 3 6005 -Historic Elevations (1971-1991) (D -NuArtion -- 6000 6000 is -f%ctinn ?r 5995 5995 5990 5990 5985 5985 5980 5980 DI -1 ari „ri 70 60 50 40 30 20 10 0 Percentage Exceedance of reservoir elevations for the Action alternative are now actually higher than the distributions for the No Action alternative. These results are substantially different from those presented in