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I OPERATIONS Reservoirs During the water year which ended September 30, 1986, the Upper Colorado River Basin yielded 18,169,000 acre-feet, or 153 percent of the long-time average. The disposition of this runoff was as follows: Acre-feet Net reservoir storage change 888,000 Evaporation loss 737,00 Bank storage change -96,000 Release to lower basin 16,640,000 Total yield 18,169,000 The water supply in 1986 ranged from 131 percent of normal on the Gunnison River above Blue Mesa Dam to 183 per- cent of normal on the Green River above Flaming Gorge Dam. Inflow to Navajo Reservoir from the San Juan River was 169 percent of normal. The April through July unregulated runoff into Lake Powell was 12,476,000 acre- feet which was 153 percent of normal. Lake Powell's water surface elevation peaked at 3,700.02 feet July 27, 1986. Water storage at Glen Canyon increased 605,000 acre-feet from October 1985 to September 1986. Flaming Gorge and Blue Mesa storages increased 344,000 and 15,000 acre-feet, respectively, and Navajo storage decreased 77,000 acre- feet. Fontenelle Reservoir in Wyoming increased 227,000 acre-feet in storage during the snowmelt season but was quickly drawn back down to its 35,000 acre-foot target storage level due to dam safety concerns. Rivers Due to high carry over reservoir content from 1985 and another high runoff year in 1986, releases from the reservoirs were higher than the minimum required for fish, recreation, or other demands. The maximum mean daily releases were 8,300 cubic fee per second (cfs) for Flaming Gorge-, 5,760 cfs for Crystal-, 3,530 cfs for Navajo, and 48,000 cfs for Glen Canyon. 13 Boating on the Colorado River near Glen Canyon Dam Night time surveillance at McPhee Dam, Dolores Project, as reservoir filling was being completed