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mum pool elevation (6,463.5 feet) which corresponds to a volume of 93,000 acre-feet of live storage. To meet these operational objectives, a constant release of approxi- mately 1,200 cfs will be made through the fall and winter months. Releases at this level will provide an appropriate level of drawdown for next season, provide greater fishery benefits and also improve water quality for downstream municipal and industrial uses. Under all but the most adverse inflow assumption, the reservoir is expected to fill in the summer of 1992. d. Navajo Reservoir With 1991 inflow at 89 percent of normal, the storage of Navajo Reservoir recovered to normal levels, although the reservoir was approxi- mately 90,000 acre-feet short offilling. During May ofl991, releases of 3,000 cfs were made in order to accommodate studies for endangered fish and to flush silt that has accumulated over the past two years of minimal release levels from the river bed. After the completion of the specific releases, discharge from the reservoir was reduced to 600 cfs. The objective is to maintain a release of 500 cfs from the reservoir to meet downstream water rights and to preserve the blue ribbon sport fishery located immediately downstream of the reservoir. The release of 500 cfs is an objective only and is not a minimum flow requirement. Under all but the most adverse inflow scenarios, Navajo Reservoir should fill in 1992. Releases from the reservoir will be held near 600 cfs through the fall and winter months, and large releases will be made in May and June in order to provide better spawning conditions for endangered Colorado squawfish located in the San Juan River. Additionally, specific releases will be made from the reservoir in order to study habitat requirements of the Colorado squawfish. These specific releases will be part of a seven-year study that is proposed by the Service to study the habitat needs of the Colorado squawfish in the San Juan River Basin. e. Blue Mesa, Morrow Point and Crystal Reservoirs (Aspinall Unit) Even though water year 1991 inflow was only 77 percent of normal, the Aspinall Unit filled in early June. The filling of the unit during 1991 was the result of only minimum releases being made during 1989 and 1990. The minimum release objective of the unit is to meet the delivery requirements of the Uncompahgre Valley Project and to keep a minimum of 300 cfs flowing through the Black Canyon of the Gunnison National Monument. 60