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<br />" <br /> <br />01.814 <br />Proposed Water Year 2005-2006 Experimental Actions <br /> <br />3 <br /> <br />DESCRIPTION OF At TERNA T1VES <br /> <br />There are two alternatives for water years 2005-2006, a No Action and a Proposed <br />Action. Both actions have the potential for several releases from Glen Canyon Dam <br />including: (I) low steady flows of approximately 8,000 cfs; (2) low daily fluctuating <br />flows in the range of 5,000-10,000 cfs; (3) daily fluctuating flows constrained by <br />provisions of the 1996 Record of Decision on the Operation of Glen Canyon Dam; and <br />(3) a high experimental flow of approximately 41,000 cfs if Pari a River and upper Marble <br />Canyon tributary sediment input targets are met. The Proposed Action, but not the No <br />Action, also includes mechanical removal of non-native fish from the Colorado River <br />above and below the mouth of the Little Colorado River and non-native fish suppression <br />flows having daily fluctuations of 5,000-20,000 cfs, <br /> <br />The two alternatives with and without sediment triggers being attained are portrayed in <br />Figures I and 2, Table 1 provides additional infom1ation on anticipated monthly dam <br />releases and daily fluctuations, while Table 2 identifies important differences between <br />the two alternatives, <br /> <br />No ACTION <br /> <br />The 2002 EA analyzed the effects of experimental high flows triggered by sediment <br />inputs from the Paria River and ungaged tributaries in upper Marble Canyon (Table 2) <br />for an indefinite period because of the uncertainty of when the trigger would be <br />attained. Attaining the first sediment input trigger on September 1 caused a change <br />from Record of Decision fluctuating flows to sequential low fluctuating and low steady <br />flows, A second trigger on October 31 caused a decision on whether to continue with the <br />sequential fluctuating and steady flows, or to return to Record of Decision flows, The <br />final trigger, on December 31, determined whether the high experimental flow would be <br />released in early January, Mechanical removal of non-native fish and winter non-native <br />fish suppression flows, in contrast, were only analyzed for the period 2003-2004, <br />Therefore, they are not part of the No Action alternative, <br /> <br />PROPOSED ACTION <br /> <br />In August 2004, the AMWG passed a recommendation to the Secretary of the Interior to <br />continue in water year 2005 all components of the experimental action that had been in <br />place during 2003-2004, Some aspects of the recommendation subsequently were <br />clarified in a conference call with the Assistant Secretary of the Interior for Water and <br />Science, Department of the Interior agency AMWG representatives were then queried <br />for their responses to a Proposed Action that largely followed the AMWG <br />recommendation, but implemented the action for both water years 2005 and 2006, <br />