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Description of Alternatives Daily and Hourly Operations Minimum flows would be 3,000, 5,000, or 8,000 cfs depending on monthly release volume, firm load, and power market conditions. The maximum flow during hourly fluctuating releases would be limited to 31,500 cfs. When high inflow volumes and storage conditions require releases greater than 31,500 cfs, such releases would be steady on a daily basis. The limit on daily fluctuations often would be more restrictive than the minimum and maximum flow rates. Fluctuations would be limited to 15,000 to 22,000 cfs over any 24-hour period, depending on the monthly release volume. Maximum flows during a minimum release year normally would not exceed 25,000 cfs. The ramp rate would follow the power load for increasing flows without restriction, but decreasing flows would be limited to 5,000 cfs per hour (winter and summer) or 4,000 cfs per hour (spring and fall). Moderate Fluctuating Flow Alternative Minimum Maximum Allowable daily Ramp releases releases fluctuations rate (cfs) (cfs) (cfs/24 hrs) (cfs/hr) 5,000 31,500 ±45% of mean flow 4,000 up for the month not 2,500 down to exceed ±6,000 Daily and Hourly Operations The Moderate Fluctuating Flow Alternative was developed to reduce daily flow fluctuations 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 intermediate flexibility for power operations. This alternative would have the same annual and essentially the same monthly operating plan as described under no action (except for the addition of habitat maintenance flows), but would restrict daily and hourly operations more than the No Action, Maximum Powerplant Capacity, or High Fluctuating Flow Alternatives. Parameters such as minimum flows, ramp rates, and allowable daily fluctuations were designed to provide resource protection through consistent release patterns throughout each month. Minimum flows for a given month would vary depending on the monthly release volume but would be no less than 5,000 cfs. The maximum rate of release for a given month also would vary depending on the monthly release volume but would be no greater than 31,500 cfs under normal Glen Canyon Dam EIS Summary 23