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Proposed Water Year 2005-2006 Experimental Actions 4 The Proposed Action in water years 2005 and 2006 contains all aspects of the Proposed Action that was implemented in water years 2003-2004, including sediment triggers for a high experimental flow, non-native suppression flows, and mechanical removal of non- native fish in the Colorado River above and below the mouth of the Little Colorado River, Modifications in the Proposed Action for water years 2005-2006 include: (1) the high experimental flow likely would be closer to 41,000 cfs than 42,000-45,000 cfs because of the drought-induced reduction in the level of Lake Powell and because of maintenance occurring at Glen Canyon Dam; (2) the timing of the high experimental flow would be moved forward from January to November-December, specifically no earlier than November 15; (3) non-native fish suppression flows with fluctuations of 5,000-20,000 cfs Monday through Saturday and Sunday fluctuations of 5,000.8,000 cfs would be extended from the end of March to April 7; (4) regardless of achieving the relevant sediment triggers, September and October releases in both calendar years 2005 and 2006 will be sequential periods of steady (8,000 cfs) and low fluctuating (approximately 6,500-9,000 cfs) flows, with duration and magnitude determined by research requirements; and (5) mechanical removal of non-native fish in the Colorado River would occur between River Miles 56,2 and 68,5, a slight reduction from previous efforts. Anticipated dam releases and periods of non-native mechanical removal for the No Action and Proposed Action scenarios are shown in Figures 1 and 2, Both the No Action and Proposed Action contain scenarios without and with sediment triggers being attained that would lead to the release of a high experimental flolV from Glen Canyon Dam, Non-native fish suppression flows during the period January 1 through the first week of April and mechanical removal of non-native fish near the mouth of the Little Colorado River would not occur under the No Action, A detailed hydrograph of the high experimental flow is provided in Figure 3, AffECTED ENVIRONMENT AND ENVIRONMENTAL CONSEQUENCES The affected environment for the No Action and Proposed Action allernatives is the same as identified in the September 2002 EA and is hereby incorporated by reference, Annual dam releases as determined by the Secretary's long-range operating criteria will be the same under both the No Action and Proposed Action alternatives; however, monthly release volumes would differ depending on if and when the high experimental flow occurs, November-December or January (Table 1), These differences also would be manifested in minor changes during the year in the elevation of Lake Powell.