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In 1998, Flaming Gorge was operated in accordance with the Biological Opinion on the Operation of Flaming Gorge Dam issued in November 1992. The biological opinion outlines the reservoir operations which may provide an improved habitat for endangered endemic species of fish. Accordingly, athree-week release at maximum powerplant capacity of 130 cubic meters per second (4,600 cfs) was made during late May through mid-June. This was followed by gradually decreasing releases until mid-summer flows of 34 cubic meters per second (1,200 cfs) were reached. In water year 1999, Flaming Gorge will again be operated in accordance with the 1992 biological opinion. A revised biological opinion on the operation of Flaming Gorge Dam is due out in December 1998. This revised opinion will likely describe specific constraints during the spring and winter seasons but may also refine the constraints for the entire year. c. Blue Mesa, Morrow Point and Crystal Reservoirs (Aspinall Unit) In water year 1998, the April through July unregulated runoff into Blue Mesa Reservoir was 851 MCM (0.690 MAF-, or 99 percent of average. Water year 1998 unregulated inflow was 1,272 MCM (1.031 MAF1, or 106 percent of average. Water year 1998 powerplant bypasses were approximately 199 MCM (0.161 MAF) at Crystal, the result of annual system maintenance and spring runoff exceeding powerplant capacity. Releases and spills up to 1 13 cubic meters per second (cros) (4,000 cfs) occurred at Crystal, with flows in the river below the tunnel in excess of 85 cros (3,000 cfs1. Blue Mesa filled easily during water year 1998. Section 7 consultation with the Fish and Wildlife Service on the operation of the Aspinall Unit continued in 1998. As part of this consultation, afive-year effort to study the effect of various release patterns on habitat, reproductive success and reintroduction of endangered fish in the Gunnison River is underway. Additionally, the Aspinall Unit was operated as if the draft contract between Reclamation, the National Park Service, and the state of Colorado to deliver water from the Aspinall Unit to the Black Canyon of the Gunnison National Monument were in place. The operation was also coordinated with the Fish and Wildlife Service and others interested in the operation of the Aspinall Unit. For water year 1999 operations, Blue Mesa Reservoir will be drawn down to at least an elevation of 2,283 meters 17,490 feet) by December 31, 1998 in order to minimize icing problems in the Gunnison River. Blue Mesa will continue to be drawn down through April 1999 to a level that will accommodate the current most probable inflow scenario and accomplish the release objectives with minimal powerplant bypasses at Crystal. The minimum release objective of the Aspinall Unit is to meet the delivery requirements of the Uncompahgre Valley Project and to keep a minimum of 8.5 cros (300 cfs) flowing through the Black Canyon of the Gunnison National Monument and to maintain a minimum of 8.5 cros (300 cfs) below the diversion structure at Redlands lat the confluence of the Gunnison and Colorado Rivers) during the summer months. Under all three inflow scenarios, Blue Mesa is expected to fill in the summer of 1999, and flows through the Black Canyon of the Gunnison National Monument are expected to be above the minimum release objective during the summer months. Filling of the reservoir in water year 1999 will ensure that 60