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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 ftsheries. However, the same releases could be detrimental to endangered and other native species of fishes. Section 7 Consultations were continued in 1993 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 1994. Studies associated with these consultations will be used to better understand the flow-related needs of the endangered and other native species of flSb. Daily releases are provided from the storage reservoirs in the Lower Basin to meet the needs of water user agencies, for river regulations, and as needed for flood control. When possible, all water passes through the powerplant units. The daily releases are regulated on an hourly basis to balance the power needs of the hydroelectric power customers, the flow needs of endangered species of fish (Upper Basin only) 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 1988 through 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 1993 was above average for the ftrst time in six years. Unregulated inflow into Lake Powell was 116 percent of average for water year 1993. Unregulated inflows for water years 1988, 1989, 1990, 1991 and 1992 were 70 percent, 54 percent, 46 percent, 71 percent and 61 percent of averages, respectively. Storage in both Lakes Powell and Mead, increased significantly in water year 1993 Lake Powell gained 5,847 million cubic meters (4,740,000 acre-feet) in water year 1993, while Lake Mead gained 2,421 million cubic meters (1,963,000 acre-feet). Operational objectives at and below Laguna Dam are to re- regulate 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 maintain 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 regulations operations below Hoover Dam, the total 1994 delivery to Mexico is scheduled to be a treaty delivery of 1,850 million cubic meters (1,500,000 acre-feet) for the calendar year. In addition, approximately 173 million cubic meters (140,000 acre-feet) of drainage waters are expected to bypass to the Gulf of California via the Bypass Drain during calendar year 1994. This bypass channel was constructed pursuant to provisions of Minute No. 242 of the International Boundary and Water Commission. 21