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o a .... c:..? .e:.. 00 That flow continued until May 18. By late May, inflows had increased dramatically. Inflow into the reservoir peaked on May 30, with a computed flow of 1775 ft3/s. Green Mountain reservoir never reached its full capacity during water year 1998. The maximum available storage volume for the water year 153,174 acre-feet, reported on July 29. That is less than 1,000 acre-feet ofthe maximum allowable storage. Reservoir storage reached the year's low of 58,619 acre-feet on April 22. A targeted storage of 60,000 acre-feet at the end of April is desired for the most probable runoff condition, while 50,000 acre-feet is desired for the maximum runoff condition. May precipitation was well below at 24 percent for the Blue River watershed. Dillon Reservoir, upstream from Green Mountain, spilled from early May through the end of the water year. Dillon Reservoir reached it maximum level on August 3, with a total volume of 256,493 acre-feet. Spillway discharges at Dillon reached a maximum of 1,004 ft% by May 30. The spill continued through the end of October for a total of81,372 acre-feet in water year 1998. Dillon Reservoir ended the water year at a storage level of251,769 acre-feet, which was 106 percent of average for the years 1966-1995 (236,800 acre-feet). Computed inflow to Green Mountain Reservoir peaked for the year at 1,775 ft3/s on May 30. June precipitation was only 54 percent of average, while inflow was average at 63 percent of average. By late July, the reservoir had reached its highest level. During July, August, & September, the inflow and turbine releases remained high due to the sustained spill from Dillon Reservoir and high snowmelt runoff conditions. Turbine releases reached a maximum flow of 998 fels on August 6. The July undepleted inflow of 86,568 acre-feet was 122 percent of average. Actual April-July runoff was 212,300 acre-feet, 78 percent of average, and 62,700acre-feet lower than the April 1 forecast of 275,000 acre-feet. Water year 1997 was wetter than average, and no Historic Users Pool (HUP) releases were needed. By contrast, water year 1998 was relatively dry, with a slightly below average run-off season followed by a summer with relatively low flows over the west slope. The Junior Shoshone Power Plant call for 158 ft3/s was on between August 26 and September 6. The call was also on between September 10 and October 31. The Shoshone Power Plant senior call was on between September 7 and September 9 due to faulty readings at the Dotsero stream gage on the main stern of the Colorado River. A flow of 1,250 ft% was granted. No calls were received based on the water rights collectively referred to as the Cameo rights. A total of 57,373 acre-feet of water (after transit looses) were delivered to the 15 Mile Reach from Green Mountain, Wolford Mountain and Ruedi reservoirs during the augmentation period (August 26 though October 31). Water year 1998 was the first year in which releases of surplus Green Mountain HUP water were made, pursuant to the 1996 Check Case Settlement (see page 23 for details on the Check Case Settlement). A total of 3 1,728 acre-feet of surplus water out of the 66,000 acre-feet HUP were delivered from Green Mountain Reservoir during the same period. By the end of the irrigation season, 34,272 acre-feet of water remained in storage at the HUP. The HUP beneficiaries did not request any releases out of their pool during water year 1998. hrigation demands remained normal until the middle of September. Thanks. to the high precipitation experienced after the middle of September, irrigation demands slightly diminished, and releases from the HUP were not required. The recorded flow at the Dotsero gage was 1,529,600 acre-feet for water year 1998, which was 8