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. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 19 To illustrate the impacts to Reach One when the Action(ALL) ruleset was triggered to achieve the 18,600 cfs objective, Figure 14 shows a sample spring hydro graph in Reach One for all three model runs. The data in this figure is from trace 37 in year 2015 from May through July. The peak release that achieved all flow objectives except the 18,600 cfs objective had a magnitude of 4600 cfs and a duration of about 16 days. Because the Yampa River triggered the Action(ALL) ruleset to attempt to achieve the 18,600 cfs objective, the peak release magnitude was reset by the Action(ALL) ruleset from 4600 cfs to 8600 cfs and the duration was decreased to 14 days. This caused a significant bypass to occur in a year when achieving all other flow objectives would not have required a bypass release. The historic year of this hydrology was 1970. For reference, the No Action model results and the historic spring releases that actually occurred at Flaming Gorge Dam in 1970 are included on the figure. Reach One Example Flow Hydrograph - Reach I Historical Year 1970, Trace 37 Year 2015 10000 8000 No Action Historical (1970) All - I All ~ 6000 '" '- ~ ~ 0 u:: 4000 2000 rvPay-o I Jul-01 Aug-O I Jun-O I Date Figure 15 shows the corresponding flows that occurred in Reach Two as a result of the release hydro graphs illustrated in Figure 14. Figure 15 shows that although the Action(ALL-l) model run did not achieve the 18,600 cfs objective, that 18,600 cfs was sustained for 11 days in Reach Two during this year. The Yampa River flows decrease very rapidly from the peak. Extending the duration of the 4600 cfs peak release would not have sustained flows in Reach Two above 18,600 cfs for three additional days.