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. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 8 FIGURE 1 90th Percentile Elevations from Januar 2002 to December 2011 Flaming Gorge Elevation 90th Percentile 6040 6030 -::;- 6020 , : ~ : c . . . . . . .. .2 .. .. 0; .. > .., G:i 6010 All 90%i1e 6000 All - I 90%i1e No Action 900/0ile All Trace 54 5990 01-2002 01-2004 01-2006 01-2008 01-2010 01-2012 Year To illustrate an example of the impacts that achieving the 18,600 cfs objective had on the reservoir elevation, Figure 2 shows trace 54 results for all three model runs during the first 10 years. Five of the 10 years shown in the figure triggered the Action(ALL) ruleset to achieve 18,600 cfs objective because of high flows experienced on the Yampa River. The years when Action(ALL) ruleset was triggered were 2002,2006,2008,2010, and 2011. In these years, the peak release from Flaming Gorge Dam was increased (if necessary) to the threshold level necessary to achieve 18,600 cfs in similar years (in some years this meant increasing to 8600 cfs and other years to 10,600 cfs). In all years except 2011 the peak release was increased by the Action(ALL) ruleset above the peak release that was calculated for the Action(ALL-l) ruleset. In 2011, the release rate estimated in both the Action(ALL) and the Action(ALL-l) rulesets was high enough to achieve the 18,600 cfs objective. The hydrology for the Upper Green River Basin during the spring of 20 11 was very wet and releases during that year were hydrologically driven to control the reservoir elevation and not by the flow objectives of the proposed alternative. The increased releases are evident by the sharp drops in elevation that occurred in the spring of each of the years mentioned above.