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001549 Other Alternatives Considered hydropower canal intake and a boatable fish ladder. The Recovery Program would not agree to fund a costly experiment to benefit recreational use of an endangered fish passage structure. 3. Construct features to create a whitewater park. This alternative would strive to achieve dual purposes of providing fish passage and providing for recreational development of this stretch of the river. Reclamation believes this water park could be designed to also maintain the necessary water surface elevation for the Ute Water pump plant and reduce potential for riverbed scour. Options include: (a) Stair-step drops: A few hundred feet upstream from the dam, construct a new water surface control structure (a dam across the river) that crests at the same elevation as the Price-Stubb Dam. Remove the top 2 to 3 feet of the Price-Stubb Dam, and at least 200 feet downstream from it, construct a second water surface control structure with a crest about 4 feet lower than the original dam crest. Finally, another 200 feet downstream, construct a third water surface control structure about 6 feet below the original dam crest. The result would be four 2-foot drops. It is believed these 2-foot drops would be passable by native fish because the drops would extend the full width of the river rather than being confined to a channel (as in the boatable fish passage previously described). The new dam upstream from the Price-Stubb would maintain the necessary water surface elevation for the Vte Water pump plant. To prevent future problems with the pump plant, the new dams would need to withstand periodic flooding and long-term erosion. Due to the extreme fluctuations in Colorado River flows (from a few hundred cfs to more than 50,000 cfs), the new dams would need to be anchored in bedrock several feet below the riverbed, adding significant costs to the project. Reclamation estimates building three such dams would cost 2 to 3 times more than building a fish ladder around the existing dam. Consequently, this alternative was eliminated from further consideration. (b) Whitewater run: Remove the dam as described in the Dam Removal alternative, and create a half-mile long, world class whitewater run. Designs might include instream river improvements such as drops, pools, broad V-shaped dams or V -shaped dams, constrictions, deflectors, and/or random boulder placements similar to those recently proposed in a conceptual plan for whitewater improvements from Palisade to Fruita (Recreation Engineering & Planning, January 1999). The ability of native fish to swim up such a chute is unknown, especially in low flow periods. Construction would require large quantities of boulders and riprap, An abundant supply of sedimentary rock is in the project area, but such rock would not withstand the long-term wear associated with whitewater conditions. The cost of importing and installing erosion-resistant boulders and riprap makes this alternative comparable in cost to the stair-step drops approach, This alternative was also eliminated due to high cost. Both the stair-step drops and whitewater run options provide the opportunity for recreational development. However, water surface elevation control and bank stabilization measures required by the Dam Removal alternative would be designed to also enhance safe boating use of the river-to the extent they would not increase Recovery Program costs for this fish passage action. 17