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I. I . 4 II. Alternative Plans Including the Proposed Action construction of the Dallas Creek Project provides the opportunity to incorporate baseload hydroelectric power to meet anticipated needs. Several powerplants and outlet works design changes (utilizing water from original project purposes) were considered and are presented below. None of the alternatives would change the size of the reservoir or affect the highway or utility relocations. Downstream flows would remain the same. A. Alternative 1 - No Action Alternative 1 is the plan approved in the FES and includes a dual outlet works and no provision for power. Dual outlets were originally designed to control water temperatures and heavy metals and thus maintain a downstream fishery conducive to trout production. Downstream water quality was supposed to improve since surface releases are warmer and contain the least amount of heavy metals. Subsequent studies have demonstrated that upper outlet temperature control will not be as significant a factor in trout production as heavy metals and summer stagnation. Although the dual outlet combined with aeration (discussed on pages 5-6) is the most environmentally desirable alter- native, benefits are only marginally better than other alternatives at much less cost. The high level outlet would be located 170 feet above the strea~ bed immediately adjacent to the spillway. This outlet would be used from April to October (most years) to provide warmer and better quality water for the downstream fishery. When reservoir elevations drop in late summer and render the upper outlet inoperable, operations would be switched to the low level outlet. B. Alternative 2 - Dual Outlet Dam; 19,240 mWh Powerplant Alternative 2 is identical to the original plan except it provides for a 4.2 megawatt (mW) capacity base load powerplant which would produce an estimated 19,240 megawatt hours (mWh) of power annually through the river outlet. The upper outlet would be used only to release water in excess of power demands. The powerplant would be operated and maintained by the Bureau of Reclamation with day to day regulation controlled by the CRSP Power Opera- tions Center in Montrose, Colorado. The plant would house two 2.1 megawatt generators; one would operate from October through March in most years when stream flows are low and reservoir releases for project uses are reduced. Both units would be engaged between April and September when more water is available. Power in excess of project needs would be distributed and marketed by the Western Area Power Administration through the facilities of the Colorado River Storage Project. A step-up transformer would be installed to raise the voltage of the generated electricity to 46 kilovolt (kV) for transmission to existing powerlines (Figure 2). This transformer and powerline would be used with any of the power alternatives.