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Description of Alternatives flows are high, steady releases within powerplant capacity (33,200 cfs) for 1 to 2 weeks in the spring. The exact month would be determined under the Adaptive Management Program and the Annual Operating Plan. Habitat maintenance flows are described in more detail under the Modified Low Fluctuating Flow Alternative. Year-Round Steady Flow Alternative Minimum Maximum Allowable daily Ramp releases releases fluctuations rate (cfs) (cfs) (cfs/24 hrs) (cfs/day) Yearly volume Yearly ±1,000 2,500 up prorated volume prorated Minimum Flow Monthly Release Volume The Year-Round Steady Flow Alternative was developed to eliminate fluctuating flows, both daily and seasonal. Year-round steady flows were designed with the goal of protecting or enhancing downstream resources by providing the greatest amounts of river-stored sediment and biomass possible in the postdam environment. Minimum flows would be determined from the mean monthly release but would correspond generally to the minimum annual release volume of 8.23 maf, which is about 11,400 cfs. The minimum release requirement would be relaxed to avoid spills during high storage or inaccurate forecast situations. The monthly volume would be approximately the annual volume divided by 12, except when response to forecast changes would be required. If forecasts changed, the volume of water to be released during the remainder of the year would be recomputed monthly based on updated forecasts, and the constant rate of release would be adjusted accordingly. The ability to maintain a constant rate of release for the entire year would depend on the accuracy of streamflow forecasts and the amount of space remaining in Lake Powell. Approximately half of the time, lake elevation would be high enough that forecast changes could cause some variations in monthly volumes. Glen Canyon Dam EIS Summary 31