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Reservoir Operations At several locations in the Colorado River Basin, minimum instream flow levels have been established which preserve the present aquatic resources downstream of certain Colorado River Basin dams. Controlled cool water releases from dams in the Colorado River Basin have provided for increased productivity of some aquatic resources and the development of significant sport fisheries. However, the same releases could be detrimental to endangered and other native species of fishes. Section 7 consultations were continued in 1992 on the operation of the Aspinall Unit on the Gunnison River and the Animas LaPlata Project on the San Juan River (which affects the operation of Navajo Reservoir). These, along with the ongoing Section 7 consultation on Flaming Gorge and the interim flow restriction on releases from Lake Powell, will continue in water year 1993. Studies associated with these consultations will be used to better understand the flow-related needs of the endangered and other native species offish. paily releases are provided from the storage reservoirs in the Lower Basin to meet the needs of water user agencies, for civer regulation, and as needed for flood control. When possible, all water passes through the powerplant units. The daily releases are regulated on all hourly basis to halance the power needs of the hydroelectric power customers, the flow needs of endangered species of fish and recreational needs. In general, controlled releases allow for an extended recreation season, and reduce the high flow periods in May and June. Water years 1987 - 1992 have been dryer than normal and a return to more normal reservoir inflow levels in future years will provide increased benefits to fish, wildlife and recreation uses. The runoff into Lake Powell for water year 1992 continued to be well below normal for the sixth straight year. Unregulated inflow into Lake Powell was 61 percent of normal for water year 1992. Unregulated inflows for water years 1988, 1989, 1990 and 1991 were 70 percent, 54 percent, 46 percent and 71 percent of normals respectively. Storage in Lake Powell and Lake Mead is down significantly. The October 1, 1992, vacant space in these two reservoirs is approximately 18.2 million acre-feet. This vacant space has resulted from six successive years of low inflow and the requirement to' maintain the minimum deliveries to meet obligations pursuant to ''The Law of the River". Operational objectives at and below Laguna Dam are to reregulate releases from Imperial Reservoir to conserve water, control sediment, and maintain the river channel. Storage above Laguna Dam in the reservoir, in surcharge, and in bank storage provides for controlled flows in the river at Yuma and the Northerly International Boundary. When combined with downstream drainage, Laguna releases provide a continuous live stream for recreation and fish and wildlife. On a few occasions each year, higher releases from Laguna Reservoir, caused by rainstorms or user rejected water orders, are used to m3intain river channel capacity. This occasional practice reduces channel maintenance expense without impairment to water conservation or power production. Based on existing reservoir conditions and river regulation operations below Hoover Dam, the total 1993 delivery to Mexico is scheduled to be a treaty delivery of 1,500,000 acre-feet for the calendar year. In addition, approximately 140,000 acre-feet of drainage waters are expected to bypass to the Gulf of California via the Bypass Drain during calendar year 1993. This bypass channel was constructed pursuant to provisions of Minute No. 242 of the International Boundary and Water Commission. 21