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reasonable specific releases required to study the protection and improvement of <br />habitat for endangered fish can be accommodated. The forecasted runoff for the <br />spring of 1999 will be closely monitored to achieve these objectives.. To protect <br />both the blue ribbon trout fishery in the Black Canyon and recreation potential, <br />releases during 1999 will be planned to minimize large fluctuations in the daily and <br />monthly flows in the Gunnison River below the Uncompahgre Tunnel Diversion. <br />d. Navajo Reservoir <br />The April through July unregulated inflow into Navajo Reservoir in water <br />year 1998 was 888 MCM (0.720 MAFI, or 93 percent of average. Water year <br />1998 regulated inflow was 1,182 MCM (0.958 MAF-, or 95 percent of average. <br />Navajo Reservoir did not fill in 1998. <br />Section 7 consultation with the Fish and Wildlife Service on the operation <br />of Navajo Dam continued in 1998. Water year 1997 was the seventh year of a <br />seven-year study to evaluate alternative operations of Navajo Reservoir to benefit <br />endangered fish, and a biological opinion on the operation of Navajo Dam is <br />expected in 1999. During the spring, large releases of up to 142 cros (5,000 cfs) <br />were made during May and June to coincide with the peak flows of the Animas <br />River. This resulted in peak flows of 306 cros (10,800 cfs) at Bluff, Utah. After <br />the completion of the large spring releases, releases were gradually reduced to <br />approximately 17 cros (600 cfs) for the remainder of the year. <br />In water year 1999, Navajo Reservoir is expected to nearly fill under the <br />most probable and probable maximum inflow scenarios. The reservoir should fill <br />above 80 percent of full under the probable minimum scenario. Releases from the <br />reservoir will be held near 17 cros (600 cfs) through the fall and winter months, and <br />large releases will likely be made in May and June in order to improve the habitat <br />and provide better spawning conditions for endangered fish in the San Juan River. <br />e. Lake Powell <br />The April through July unregulated inflow into Lake Powell in water year <br />1998 was 9,498 MCM (7.700 MAF) or 100 percent of average. Water year 1998 <br />unregulated inflow was 15,509 MCM (12.573 MAF-, or 107 percent of average. <br />Lake Powell ended the water year 14 feet from full. <br />During water year 1999, releases greater than the minimum release <br />objective of 10,152 MCM (8.230 MAF) likely will be made to avoid anticipated <br />spills and/or to equalize the storage between Lakes Powell and Mead. Under the <br />most probable inflow conditions, releases of 13,198 MCM (10.700 MAF) would be <br />made, while under the probable maximum inflow scenario, approximately 20,846 <br />MCM (16.900 MAF) will be released. This maximum probable inflow would require <br />releases of about 708 cros {25,000 cfs) for a lengthy period of time. With current <br />full reservoir system conditions, releases above powerplant capacity are possible in <br />1999. Such releases would be made consistent with the 1956 Colorado River <br />Storage Project Act, the 1968 Colorado River Basin Project Act, the 1992 Grand <br />Canyon Protection Act, and the Secretary of the Interior's agreement for managing <br />spills from Glen Canyon Dam contained in the 1996 Annual Operation Plan. This <br />agreement provides for the use of reservoir releases in excess of powerplant <br />capacity required for dam safety purposes during high reservoir conditions to <br />accomplish the objectives of the beach/habitat-building flow described in the ROD <br />61 <br />