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<br />June, releases were increased dramatically because the sudden increase in snowfall for May for <br />the entire Blue River drainage. Since this runoff period, we filled Green Mountain Reservoir <br />three times in the month of July. For the 1999 water year, the release for natural flow shortages <br />was not called for on the Colorado River at the Shoshone Power plant due to the high natural <br />flows. For the irrigation season, no calls for water were made due to high inflows to Dillon and <br />Green Mountain. <br /> <br />Reservoir storage reached the year's low of 67,146 acre-feet on April 22. A targeted storage of <br />60,000 acre-feet at the end of April is desired for the most probable runoff condition, while <br />50,000 acre-feet is desired for the maximum runoff condition, which was the runoff condition <br />forecasted for Green Mountain in 1999. <br /> <br />May precipitation was above average at 145 percent for the Blue River watershed. Due to the <br />expected high runoff conditions, Dillon Reservoir spilled from early May through the end of <br />October, 1999. Dillon Reservoir filled to capacity on August 6, 1999, with a total volume of <br />257,120 acre-feet. Spillway discharge at Dillon reached a maximum of 1,793 fefs by June 24, <br />1999. The spill continued through the end of October for a total of 163,902 acre-feet in water <br />year 1999. Dillon Reservoir ended the water year at a storage level of 254,852 acre-feet, which <br />was 108 percent of average for the years 1966-1995 (236,800 acre-feet). <br /> <br />Computed inflow to Green Mountain Reservoir peaked for the year at 2,809 ft3fs on June 24, <br />1999. June precipitation was 116 percent of average and inflow was above average at 121 <br />percent of average. On Friday, July 9, 1999, the water level had reached 7949.35 feet, with a <br />total storage of 152,264 acre-feet. Due to high water levels, 1550 acre-feet were spilled through <br />the radial gate for the next three days. <br /> <br />During July, August, & September, the inflow and turbine releases remained high due to the spill <br />of Dillon Reservoir and high snowmelt runoff conditions. Turbine releases were at the capacity <br />of 1500 ft3fs during early July. The July undepleted inflow of 86,568 acre-feet was 122 percent <br />of average. Actual April-July runoff was 299,709 acre-feet, 115 percent of average, and 19,709 <br />acre-feet more than the April 1 forecast of 280,000 acre-feet. <br /> <br />Due to the spring and early summer rain and snowmelt, no requests were received for water from <br />the Green Mountain Reservoir. That includes Grand Valley Irrigators or the Shoshone Power <br />Plant. A total surplus of 35,566 acre-feet from the Historic Users Pool (HUP) was released <br />between September 1 and November 3, 1999. BY the end of the irrigation season, 30,434 acre- <br />feet of water remained in storage in the HUP. No releases were needed for the west slope HUP <br />beneficiary at any time in 1999. An agreement was in place to deliver surplus HUP water to the <br />Grand Valley Power Plant and a draft agreement to deliver surplus HUP water in excess ofthe <br />power plant capacity for municipal recreational uses was being prepared. <br /> <br />The Green Mountain HUP Managing Entities, established under the settlement of the Orchard <br />Mesa Check Case, held their first meeting for 1999 in Grand Junction on June 14. The target <br />flows for the 15 Mile Reach (15 MR) were set by the Fish and Wildlife Service at 1240 ft3/S for <br />the 1999 irrigation season. Releases of surplus HUP water are normally coordinated with <br /> <br />9 <br />