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Description of Alternatives <br />Seasonally Adjusted Steady Flow Alternative <br />Minimum <br />releases <br />(cfs) Maximum <br />releases <br />(cfs) Allowable daily <br />fluctuations <br />(cfs/24 hrs) Ramp <br />rate <br />(cfs/day) <br />8,000 Oct-Nov 18,000 ±1,000 2,000 between <br />8,500 Dec months <br />11,000 Jan-Mar <br />12,500 Apr <br />18,000 May-Jun <br />12,500 Jul <br />9,000 Aug-Sep <br />The Seasonally Adjusted Steady Flow Alternative was developed to <br />enhance the aquatic ecosystem by releasing water at a constant rate within <br />defined seasons and by using habitat maintenance flows. Seasonal <br />variations in minimum flows and habitat maintenance flows were <br />designed with the goal of protecting and enhancing native fish. Monthly <br />release patterns would differ from the No Action Alternative as explained <br />in more detail below. <br />This alternative would provide steady flows on a 1- to 3-month basis, <br />providing seasonal variations throughout the year to meet downstream <br />resource needs. The highest releases would occur in May and June, with <br />relatively low releases from August through December. <br />Minimum <br />Flow The minimum monthly constant release for each season is shown above. <br />These minimum release requirements would be relaxed to avoid spills <br />during high storage or inaccurate forecast situations. <br />Monthly Release <br />Volume Releases within each month would be steady and would have to equal or <br />exceed the monthly minimums. Any additional water in excess of the <br />minimum annual release volume would be distributed equally among the <br />12 months, subject to an 18,000-cfs maximum. This 18,000-cfs maximum <br />would be exceeded when the annual release is more than 13.14 maf. If <br />forecasts changed, the volume of water to be released during the <br />remainder of the year would be recomputed monthly based on updated <br />forecasts, and the constant rate of release would be adjusted accordingly. <br />Habitat Maintenance Flows. Habitat maintenance flows are included in <br />this alternative to re-form backwaters and maintain sandbars, which are <br />important for camping beaches and fish habitat. Habitat maintenance <br />30 Glen Canyon Dam EIS Summary