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<br />o <br />o <br />N <br />c;. <br />c:} <br /> <br />There was pumping during October, November, April and June, but the total volume was only 5.300 <br />acre-feet. By contrast. the 3D-year average volume is 27,650 acre-feet. <br /> <br />During the Water Year 2002, a total of 8,800 acre-feet of controlled releases into the river were made <br />out of Willow Creek Reservoir. That total was the lowest volume in 20 years. <br /> <br />t.l-' <br /> <br />Granbv Reservoir <br /> <br />Completed in 1950, the Granby Reservoir on the upper Colorado River collects and stores most of <br />the water supply for the C-BT. The reservoir stores the flow of the Colorado River as well as water <br />pumped from Willow Creek Reservoir. The reservoir has a total storage capacity of539,800 acre- <br />feet. The spillway is located on the left abutment. Flows over the spillway are controlled by two <br />radial gates, with a total release capacity of II ,500 ft3 Is. The Granby Pumping Plant has three units <br />with a combined installed capacity of 600 ft3 Is. <br /> <br />Reservoir carryover storage into Water Year 2002 was 374,219 acre-feet, which is 63,800 acre-feet <br />below the 3D-year average of 438,000 acre-feet. <br /> <br />A total of 12.06 inches of precipitation was reported for th:: Lake Granby watershed for Water Year <br />2002. That total was only 70 % of the average. Taking into account the low precipitation totals <br />during the first few months of the Water Year, the March I forecast for April-July was estimated at <br />169,000 acre-feet of storage. That forecast was 28,000 acre-feet below the average. By April I ,the <br />expectations were significantly lower, as the dry weather continued to dominate. The forecasted <br />volume for the period May-July was only 135,000 acre-feet. That total was 62,000 lower than the <br />historical average. Inflow into Lake Granby remained close to or slightly above the 3D-year average <br />until late April. But, by the beginning of May, runoff volume began to fall below the average. By <br />late June, most of the snowpack had dissipated and the runoff was diminishing. The total Anril-July <br />runoff was 79,500 acre-feet, which represents 38 % of the 3D-year average. The April-July runoff for <br />Water Year 2002 was the lowest ever reported at Granby Reservoir. <br /> <br />Except for the month of June, during the peak of the runoff season, the reservoir storage at Lake <br />Granby continued to decline steadily throughout the Water Year. The water surface level dropped <br />approximately 38 feet during the year, causing problems for recreationist and marina operators. With <br />the reservoir storage at critical low levels, a total of26,600 ft3 Is used for river releases was restricted <br />to the required minimum daily flow rates. As was the case during Water Year 2001, there was no <br />water spilled from Lake Granby during Water Year 2002. Windy Gap did not pump to Granby <br />during Water Year 2002. <br /> <br />Lake Granby ended the Water Year with 176,778 acre-feet in storage. This volume was 261,300 <br />acre-feet below the 3D-year average, and almost 200,000 acre-feet lower than the volume recorder on <br />September 30. 200 I. <br /> <br />10 <br />