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WATER YEAR 1997 OPERATIONS Green Mountain Reservoir Green Mountain Reservoir and Power Plant, completed in 1943, are located on the Blue River on Colorado's western slope. The reservoir with a total capacity of 154,645 acre-feet provides storage water releases for power production, replacement of out-of-priority depletions, and contract water deliveries. The power plant has two units with a total installed capacity of 26 megawatts. The spillway located on the left abutment is controlled by three 25 x 22 foot radial gates and has a total release capability of 25,000 ft3/S. Reservoir storage carried over from water year 1996 to water year 1997 was 125,500 acre-feet compared to an average September 30 storage of 128,700 acre-feet. Colorado River native flows were above average during October, averaging 1,383 ft3/s at the Dotsero gage. This flow was adequate to meet downstream water user demands and resulted in no need for natural flow shortage releases from Green Mountain Reservoir to meet the needs at the Cameo gage during October. Turbine releases averaged 321 ft3/s during October. The turbine releases averaged 427 ft3/s during November. Winter turbine releases (December through January) averaged 449 ft3/S to meet replacement requirements, bypass of inflow, power production, and the desired end-of-January storage position. The end-of-January storage for Dillon Reservoir was 223,600 acre-feet, 19,500 acre-feet lower than the previous year and 100 percent of average (223,400 acre-feet). The October-January precipitation for the Green Mountain Reservoir watershed was well above average at 162 percent of the 1966-1995 average. Similarly, the February 1 snow-pack water content data was recorded at 178 percent of average. By February 1, storage at the reservoir had been reduced to 93,000 acre-feet. Reservoir storage continued close to plan during February, and releases averaged 408 ft3/s. Precipitation for February was below average at 75 percent of the 1966-1995 average, 0.90 inches. Precipitation remained below average in March at 58 percent of average and the snow-pack water content was 116 percent of average. Precipitation for October-March remained well above normal at 127 percent of average, an average of 9.76 inches for the 4 rainfall gages in the watershed. March inflow was 157 percent of average. Turbine releases were increased to an average 456 fr3/s during March to pass inflow, replace water for out of priority Project depletions, and to release storage for western slope downstream depletions. During April, the snow-pack water content increased substantially to 140 percent, and the April- 8