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I I I I I I I I I I I I I I I I I I I inflow into Navajo Reservoir in water year 1999 ended up being 774 MCM (0.627 MAP) or 81 percent of average, Water year 1999 regulated inflow was 1,486 MCM (1.204 MAF) or 112 percent of average, Navajo Reservoir reached a peak elevation of I 854.05 meters (6082.83 feet) on August 12, 1999. During the spring, large releases of up to 142 ems (5,000 efs) were made during May and June to coincide with the peak flows of the Anintas River. This resulted in peak flows of 2 I 0 cubic meters per second (7,400 cfs) at Bluff, Utalt. Section 7 consultation with the Fish and Wildlife Service on the operation of Navajo Dam continued in 1999. Water year 1997 was the last year ofa 7 year study to evaluate alternative operations of Navajo Reservoir to benefit endangered fish. A report entitled "Flow Reeommendations for the San Juan River", which outlines flow recommendations for the San Juan River below Navajo Dam, has been eompleted by the San Juan Recovery Implementation Program (SJRIP). This report was finalized in 1999 by the SJRIP. In water year 2000, Navajo Reservoir is expected to nearly fill under the probable maximum inflow scenario. The reservoir should fill above 80 percent of full under the most probable and probable minimum scenarios. Releases from the reservoir will be held near 14 cms (500 efs) through the faIl and winter months and large releases will likely be made in May and June pursuant to the flow recommendations to improve the habitat and provide better spawning conditions for endangered fish in the San Juan River. Lake Powell The April through July unregulated inflow into Lake Powell in water year 1999 was 9,400 MCM (7.62 MAP) or 99 pereent of average. Water year 1999 unregulated inflow was 15,680 MCM (12,71 MAP) or 108 percent of average. Lake Powell nearly filled in water year 1999 reaehing a peak elevation of 1126.15 meters (3694.72 feet) on July 16, 1999 (5.28 feet from full). During water year 2000, releases greater than the minimum release objective of 10,152 MCM (8.230 MAP) will likely be made to avoid anticipated spills and/or to equalize the storage between Lakes Powell and Mead. Under the most probable inflow conditions, releases of 14,370 MCM (11.650 MAP) would be made, while under the probable maximum inflow scenario, approximately 21,650 MCM (17.550 MAP) will be released. With current full reservoir system conditions, releases above powerplant capacity are possible in 2000. Such releases would be made consistent with the 1956 Colorado River Storage Project Act, the 1968 Colorado River Basin Project Act, the 1992 Grand Canyon Protection Act, and the Secretary of the Interior's agreement for managing spills from Glen Canyon Dam, initially made in the 1996 AOP. This agreement provides for the use of reservoir releases in excess ofpowerplant capacity required for dam safety purposes during high reservoir conditions to accomplish the objeetives of the Beach/Habitat Building Flow described in the Record oIDecision for the Glen Canyon Dam Final Environmental Impact Statement (GCDFEIS). December I, 1999 IO