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I I ,I I, I I I I I I I I I I I I I I I D~:J~;7:~ precipitation. By the end of the water year, turbine releases were high at 500 ft3/s and reservoir storage stood at a very low 78,927 acre-feet, which was 48,373 acre-feet below average. The total 1990 water year inflow of 303,700 acre-feet was 66,700 acre-feet below the 1960-1989 average inflow of 370,400 acre-feet. Blue River, Dillon Reservoir, and Green Mountain Reservoir operations for water year 1990 are summarized in table 2. Gross generation at the powerplant totaled 40,300,000 kilowatt-hours for the water year. This was 18,100,000 kilowatt-hours below average. Willow Creek Reservoir Completed in 1953, Willow Creek Reservoir has a total storage capacity of 10,600 acre-feet. The uncontrolled spillway, located at the left abutment, has a capacity of 3,200 ft3/s. The Willow Creek Feeder Canal begins at the left abutment with a capacity of 400 ft3/s for pumping to Granby Reservoir. Reservoir carryover storage coming into water year 1990 was 8,194 acre-feet. This was below the 30-year average of 9,000 acre-feet. During October and November, the reservoir was drawndown to near 7,200 acre-feet to provide storage space for winter inflows. The release to the river for fishery habitat and for irrigation demands totaled 1,639 acre-feet, and 603 acre-feet was pumped to lake Granby. The minimum reservoir content for the water year was 7,207 acre-feet on November 8. October-January inflows were below normal at only 70 percent of average. Precipitation for the October-January period was below average at 70 percent of average. ' The February 1 snow-water content was only 58 percent of average, which resulted in an April-July runoff forecast of 35,000 acre-feet. The March 1 snow-water content increased to 79 percent of average and the April-July runoff forecast increased to 40,000 acre-feet. March precipitation increased sharply to 205 percent of average with 2,52 inches recorded. Duri ng the October through March peri od, precipitation in the Willow Creek watershed averaged 98 percent of normal. Snowpack water content for the April 1 measurement was 87 percent of average. The April-July snowmelt runoff forecast remained at 40,000 acre-feet or 80 percent of normal, Inflows were above average at 109 percent of normal duri ng March, ' The natural inflow increased steadily in April from 26 ft3/s on April 1 to 119 ft3/s on April 24. However, the total April inflow was below normal at 83 percent of average, A total of 3,522 acre-feet was pumped to lake Granby during the month. April had above normal precipitation at 126 percent of average, but the May 1 snowpack water content was only 51 percent of average. The April-July runoff forecast remained at 40,000 acre-feet. 11