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January 7, 2004 16 <br />on September 30, 1999). As water year 2003 ended on September 30, 2003, Lake Powell storage <br />had been reduced to 12.1 maf (14,900 mcm) or 50 percent of capacity. <br />Lake Powell began water year 2003 with 14.5 maf (17,800 mcm) of water in storage (59 percent of <br />capacity). Storage in Lake Powell at that time was 2.6 maf (3,200 mcm) lower than that of Lake <br />Mead. Because of reduced storage, and Lake Powell storage being below Lake Mead, releases from <br />Glen Canyon Dam were scheduled to maintain the minimum release objective from Lake Powell of <br />8.23 maf (10,150 mcm) for water year 2003 in accordance with Article 11(2) of the Operating <br />Criteria. Forecasted inflow to Lake Powell was significantly below average throughout water year <br />' 2003, and storage equalization releases between Lake Mead and Lake Powell were not required. The <br />total release from Lake Powell in water year 2003 was 8.23 maf (10,150 mcm). <br />' April through July unregulated inflow into Lake Powell in water year 2003 was 3.92 maf (4,830 <br />mcm), or 49 percent of average. Water year 2003 unregulated inflow was 6.4 maf (7,845 mcm), or <br />53 percent of average. Lake Powell reached a peak elevation of 3,616.6 feet (1,102.3 meters), 83.4 <br />' feet from full, on June 23, 2003. The elevation of Lake Powell on September 30, 2003, was 3,603.7 <br />feet (1,098 meters), 96.3 feet from full. The water surface of Lake Powell had not been this low <br />' since 1973, prior to the reservoir's first filling in 1980. <br />On April 24, 2002, members of the Glen Canyon Adaptive Management Work Group (AMWG) <br />recommended to the Secretary that an experimental flow test be made from Glen Canyon Dam <br />' beginning in water year 2003. The recommendation addressed the decline of two key resources in <br />the Grand Canyon: sediment and population viability of endangered humpback chub. Reclamation, <br />' the National Park Service, and the United States Geological Survey jointly prepared an <br />Environmental Assessment (EA) under the National Environmental Policy Act (NEPA) to document <br />the impacts of these proposed experimental flows. The Proposed Experimental Releases from Glen <br />' Canyon Dam and Removal of Non - Native Fish EA (September 2002) incorporates a Biological <br />Assessment for the Fish and Wildlife Service under the Endangered Species Act (ESA). A Finding <br />of No Significant Impact on the experimental releases was signed by the three agencies on December 6, <br />' 2002. <br />Daily high fluctuating releases from Glen Canyon Dam, as part of the experimental flows, were <br />' carried out from January through March, 2003. Releases during this three month period ranged <br />between a high of 20,000 cubic feet per second (cfs) to a low of 5,000 cfs each day. The January <br />through March high fluctuating releases were intended to benefit the endangered humpback chub by <br />' reducing the spawning and recruitment of nonnative fish. These same high fluctuating releases are <br />scheduled to be repeated in January through March of 2004. <br />' Retention of sediment in the Grand Canyon is also an aspect of the experimental flows. If significant <br />sediment input (over one million metric tons) to the Grand Canyon from the Paria River had <br />occurred in the summer or fall of 2003, and 800,000 metric tons were retained by January 1, 2004, as <br />described in the EA, a 2 -day test release of 42,000 to 45,000 cfs from Glen Canyon Dam would have <br />been made in 2004, as part of the experimental flows, to understand mobilization of sediment and <br />' beach and habitat creation in the Grand Canyon corridor. Additionally, the 2 -day test releases of <br />A <br />