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from the Cache la Poudre River north of Ted's Place. The second largest water supply feature was conceptually planned on the mainstem and North Fork of the Cache la Poudre River. The mainstem reservoir (Cache la Poudre Afterbay or Grey Mountain Reservoir) could provide approximately 200,000 ac-ft of water storage. In addition, the mainstem reservoir would provide flood protection for the City of Fo(t Collins, a means of diverting water by gravity from the mainstem and North Fork of the Cache la poudre River into Glade Reservoir, power generation from flow releases to the Poudre River through a conventional hydroelectric power plant, and would serve as the afterbay reservoir for a separate pumped-storage hydroelectric power plant situated either above or below ground surface on the north shore of the reservoir. The third reservoir, the Cache la Poudre Forebay, was conceptually sited west of Greyrock Mountain. This reservoir would provide 30,000 to 50,000 ac-ft of storage at an elevation approximately 1400 ft above the Poudre River for operating the pumped-storage hydroelectric plant. The objective of studying the feaSibility of hydroelectric power facilities was to determine whether the electric power generating capacity could reduce the cost of providing the water supply. Feasibility studies for the project were initiated in 1986 using funding from a private entity interested in marketing the electric power that could be generated from the hydroelectric facilities. However, the District recognized the necessity of considering all viable alternatives for water supply and potential hydroelectric power generation before finalizing plans for a particular project. Therefore in 1985, concurrent with preparing the application for an F~RC Preliminary Permit, the District submitted an application to the Colorado Water Resources and Power Development Authority to perform a basin-wide study to independently evaluate alternative measures that would provide for the efficient and environmentally sound development of water and hydroelectric power resources in the Cache la Poudre Basin. It waS the specific intent of this basin-wide study to identify and evaluate ~ny alternative measures, including nonstructural and conservation measufes as well as structural measures, that might be less costly and have less e~vironmental impacts than the project proposed by the District in the FrRC Preliminary Permit Application. The Authority accepted the District's aprlication and initiated the Cache la Poudre Basin Study during the summer of 1985. The Authority's Cache la poudre Basin Study was completed in 1986 and confirmed a number of the conclusions the District had reached concerning water supply storage and the potential for hydroelectric power generation in the Poudre Basin. First, the Basin Study demonstrated the need for additional water supply storage in northeastern Colorado to minimize the economic consequences of a major drought. Secondly, although 32 nonstructural, water conservation, and water management measures were identified and evaluated, the Basin Study concluded that even if the viable- nonstructural measures were to be implemented, the need for additional water supply storage would not be eliminated. Thirdly, based on prefeasibility evaluations of 5 damsites on the mainstem of the Cache la Poudre River below Poudre Park, one damsite on the South Fork, 3 damsites on the North Fork (including replacement or modification of 2 existing dams), and one off-channel damsite, a preferred configuration of a multiple purpose water supply project was recommended based on consideration of pertinent economic, environmental, and engineering factors,. The configuration of the - 2 -