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Crystal Dam releases water to the Gunnison River through its powerplant and river outlets. The outlets can release up to 2,030 and 2,100 cubic feet per second (cfs), respectively. When releasing water to meet any purpose, the BOR historically minimized use of the non- power generating river outlet (and the spillway). The only diversion of the releases before the Black Canyon and the Gunnison Gorge is through the Gunnison Tunnel of the Uncompahgre Valley Reclamation Project (Uncompahgre Project) and is physically capable of diverting up to 1,135 cfs. When operation of Blue Mesa Dam began in 1965, minimum flows of 100 cfs through the Black Canyon were provided. With construction of Crystal Dam and Reservoir in 1976, the BOR increased these minimum flows to 200 cfs. On the basis of instream flow studies for the Gold Medal Trout fishery, the BOR increased minimum releases in 1985. Since that time, the BOR's goal has been to maintain at least 300 cfs through the Black Canyon, except during extreme drought or emergencies. A combination of the natural flow conditions, water passed to downstream senior water rights, and water stored in Blue Mesa Reservoir and released for hydropower generation purposes has historically maintained the minimum flow. In 1975, an exchange agreement was reached among the BOR and three non-Federal parties, the Uncompahgre Valley Water Users Association, Colorado River Water Conservation District, and Upper Gunnison River Water Conservancy District, which provided for the exchange of water between Taylor Park Reservoir (a storage feature of the Uncompahgre Valley Reclamation Project constructed on a tributary of the Gunnison River upstream of the Aspinall Unit) and Blue Mesa Reservoir. This unique 1975 Agreement provides for water released from the upstream Taylor Park Reservoir to enhance fish and recreational flows to then be credited and stored in Blue Mesa Reservoir. When needed for irrigation of lands in the Uncompahgre Valley, the water is then released by the Aspinall Unit dams, and diverted through the Gunnison Tunnel. Using concepts developed during 1991, BOR began holding meetings with concerned parties each January, April, and August to coordinate and detennine the operation of the Aspinall Unit for the period between each meeting. Operating decisions made at these meetings consider water supply forecasts and implications to the 24-month studies for all the Colorado River Storage Project reservoirs. Input from affected agencies has resulted in BOR meeting requests for irrigation, power generation, and instream flows as well as requests for special flows needed for various endangered fish, trout, and sedimentation studies. 3