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provides hydropower to the southwestern United States. Blue Mesa and Morrow Point are operated to meet peak power demands. Crystal provides firm power supplies while stabilizing river flows. Flood control is provided to the downstream cities of Delta and Grand Junction as well as intervening railroads, highways, and farms and ranches. Water exchange agreement opportunities are created that enhance the public uses of the Taylor River and Taylor Park Reservoir. In addition, stored water is available for future use and Compact development in Colorado. In 2000, Reclamation finalized a long-term commitmentto allow Aspinall Unit water rights to be subordinated up to 60,000 acre-feet for upstream in-basin development. These existing and future uses can be affected by changes in operations which attempt to meet the flow recommendations as discussed in the following sections. It must be noted, this is a preliminary analysis due to time and data constraints. Operating to meet the flow recommendations does not create additional water in the river on an annual basis; it redistributes flows, with increased flows at one time of the year and decreased flows at another. The model runs, with current assumptions indicate the flow recommendations are not fully met. In order to more fully meet these recommendations, impacts on many project purposes would be more severe than described below. Hvdropower The Western Area Power Administration (Western) is preparing a more detailed analysis of power marketing issues and impacts. The following is a preliminary analysis prepared by Reclamation. The Aspinall Unit powerplants have a total operating capacity of272 megawatts. Powerplants at Blue Mesa and Morrow Point are used as peaking units while Crystal Dam and Powerplant are used to make uniform releases to the Gunnison River. Since the Record of Decision for Glen Canyon Dam and peaking restraints at Flaming Gorge Dam, the relative importance of the Aspinall Unit to energy production has increased. The Aspinall Unit powerplants now contribute a significant portion of the "peaking" or "demand-following" requirements of Western contractual obligations. In the summer of 2001, Western estimates that the Aspinall powerplants produced about 45 percent of the "demand- following" of the Colorado River Storage Project system. A preliminary power generation analysis table has been prepared. This table shows that on average the operations under the flow recommendations decrease power production and revenues. In certain years such as the dry year of 1977, the flow recommendations pull more water out of storage and generation increases for that year, but is decreased in following years as Blue Mesa storage is recovered. Under certain hydrologic conditions, the total amount of electricity produced in a given year will be reduced when water flows throl,lgh the outlet tubes and/or the spillway and thus bypasses the powerplant. Water that bypasses the powerplant in the spring is water that might have otherwise been stored and released later during the hot summer months when the demand for power is high. An approximation of the amount of this foregone generation can be estimated by considering the difference between the annual generation under the baseline condition and the annual generation under a proposed scenario. 7