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Description of Alternatives operations. When high inflow volumes and storage conditions require releases greater than 31,500 cfs, such releases would be steady on a daily basis. Because of restrictions on daily fluctuations and ramp rates, maximum flows during a minimum release year normally would not exceed 22,300 cfs. The ramp rate would be limited to 4,000 cfs per hour for increasing flows and 2,500 cfs per hour for decreasing flows. Habitat Main- tenance Flows Allowable daily fluctuations as well as minimum and maximum flows would be determined based on the mean releases for the month. The allowable fluctuation would be plus or minus 45 percent of the mean daily flow, not to exceed plus or minus 6,000 cfs. Habitat maintenance flows are included in this alternative to re-form backwaters and maintain sandbars, which are important for camping beaches and fish habitat. Habitat maintenance flows are high, steady releases within powerplant capacity (33,200 cfs) for 1 to 2 weeks in spring. The exact month would be determined under the Adaptive Management Program and the Annual Operating Plan. A more complete description of habitat maintenance flows can be found under the Modified Low Fluctuating Flow Alternative that follows. Modified Low Fluctuating Flow Alternative (Preferred Alternative) Minimum Maximum Allowable daily Ramp releases releases fluctuations rate (cfs) (cfs) (cts/24 hrs) (cfathr) 8,000 between 25,000 5,000 4,000 up 7 a.m. and 7 p.m. 6,000 or 8,000 1,500 down 5,000 at night The Modified Low Fluctuating Flow Alternative was developed to reduce daily flow fluctuations well below no action levels and to provide special high steady releases of short duration, with the goal of protecting or enhancing downstream resources while allowing limited flexibility for power operations. This alternative would have the same annual and essentially the same monthly operating plan as described under the No Action Alternative but would restrict daily and hourly operations more than any of the previously described fluctuating flow alternatives. Additional information on the effects of dam operations has been gathered since the interim operating criteria were developed. Some of this preferred 24 Glen Canyon Dam EIS Summary