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. Steady Flows, including the Existing Monthly Volume, Seasonally Adjusted, and Year-Round Steady Flow alternatives. These alternatives provide a full spectrum of analysis ranging from flows that exceed historic peaking power operations to flows that would essentially remain constant year-round. Depending upon the alternative, peaking power production would range from fully maximized to severely limited. Under the preferred alternative, river flow fluctuations from the historic range are narrowed. The ramping rate, which is the rate of change in river flows, both up and down, is restricted. Also, the daily volume of change is constrained from the historic pattern. This serves to meet the needs of the various riverine environments and to protect recreational uses of the river, while providing for a limited amount of peaking power capability. The EIS team and cooperating agencies attempted to balance benefits to all resources in identifying a preferred alternative. Thus, as a result of comments received on the draft EIS and discussions with the u.S. Fish and wildlife service, the preferred alternative as described in the draft EIS is somewhat different in the FEIS. The flow modifications to the preferred alternative include an increase from 20,000 to 25,000 cubic feet per second (cfs) maximum flow and an upramp increase from 2,500 to 4,000 cfs per hour. These changes were reviewed and agreed upon by the cooperating agencies, other interested parties, and the Glen Canyon Environmental Study senior scientist and his advisory panel. In addition to the operational changes in maximum flows and upramp rates, the endangered fish research flows, as detailed in the Fish and Wildlife Service biological opinion (Endangered Species Act), were moved to the Adaptive Management Program. Also identified in the biological opinion is the need for temperature modification of the Colorado River as a critical factor benefiting endangered fish in the Grand Canyon. Reclamation will, be requesting funds to expeditiously complete the needed studies to move forward with selective withdrawal structures at the dam which will allow warmer water near the surface of the reservoir to be released, thus raising the river temperature. The FEIS was prepared in accordance with the Grand Canyon Protection Act, which required a reevaluation of dam operations to minimize adverse impacts on the downstream environmental and cultural resources and Native American interests in Glen and Grand Canyons. Reclamation involved a number of Federal, state, and Native American interests as cooperating agencies, including the Bureau of Indian Affairs, U.S. Fish and Wildlife Service,