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MINIMUM REQUIRED RESERVOIR RELEASES o Minimum releases are required from some system facilities to satisfy prior water rights and fish and ) wildlife requirements. ,.. ~ Ut On January 19, 1961, the Secretary ofthe Interior established specific guides for water releases out of --J Lake Granby, which satisfy fish requirements. A release from Lake Granby of 20 fe Is is required from October through April of each year. During the remaining months of the year, the control point is almost 3 miles downstream from the dam at the YMCA gauging station. Although the seepage from Granby Dam and some inflow from tributaries enter this section of stream, there are also diversions for several irrigation ditches between Granby Dam. and the control point. Except in years of subnormal inflow, a flow of 75 ft% during the May-July period, 40 fels during August, and 20 fels during September is required at this location, downstream of Lake Granby. The flow during the May-September period can be reduced if forecasts indicate that the inflow during the water year to Shadow Mountain Lake, Grand Lake, and Lake Granby (less the decreed rights in the reach of the Colorado River between Granby Dam and the mouth of the Fraser River) and the water capable of being pumped from Willow Creek Reservoir during that year, are 230,000 acre-feet or less. The following reduction of fishery flow below Lake Granby will apply on the basis of a forecast to be made by the Bureau of Rec1amation during the last week in April, using information from all available sources. Forecast Inflow in Acre-Feet Percentage Reduction in Minimum Release 220,000 - 230,000 210,000 - 220,000 195,000 - 210,000 Less than 195,000 15 20 25 30 Adjustments will be made in the reductions, when appropriate, based on revised forecasts and consideration of actual flows during May, June, and July. Willow Creek below Willow Creek Reservoir is not considered a fishery resource since an irrigation ditch a short distance below the dam generally uses the entire flow in the late summer months. In the Secretarial determination, no releases were provided to maintain Willow Creek as a live stream. However, a release of7 ft3 Is or inflow (whichever is the lesser) from Willow Creek Reservoir is required during the October-April period to augment fishery flows in the Colorado River. A minimum release of 35 ft3 Is for September and October, 45 ft% from November through December, 20 fels from January through May, 50 ft3/s in June and July, and 40 fels in August or inflow (whichever is the lesser) is made from Shadow Mountain Lake to maintain fish and wildlife in the Colorado River above Lake Granby. The minimum release required out of Green Mountain Reservoir is controlled by, senior adjudicated water rights downstream from the project. Inflow to Green Mountain Reservoir is released, as required, 17