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001571 Fish and Wildlife Resources aquatic habitat in the riffle passageway and plunge pool below the dam and due to probable endangered fish occupancy, the licensee was required to provide a year-round minimum flow of 200 cfs in the 2,250-foot-long bypass reach downstream from the dam. Another concern was for injury and loss ('impingement' and/or 'entrainment') of fish as Colorado River flows are diverted to the power canal and passed through the proposed powerhouse. To ensure project operation would have the least impact on the river's fishery resource, the licensee was to consult with the Colorado Division of Wildlife and the Department of the Interior to design and construct fish screens, with the screen mesh openings to be as small as possible, at the canal and/or powerhouse intakes. The 1990 license also prohibited any work in the river during July through September to avoid impacts to Colorado pikeminnow during spawning and larval development. Fish Ladder with Hydropower Plant: The ladder would be similar to the Redlands fish ladder constructed in June 1996. Since its completion, 42 Colorado pikeminnow and over 26,000 native fish have passed through the Redlands fishway. Installation of a fish trap to allow selective passage would prevent upstream access by nonnative fish. A fish trap at this location has some advantages over a fish trap at the Grand Valley Project Diversion Dam about 5 miles upstream (see Dam Removal impacts below). No harm (taking) to any life stage of endangered fish is expected as a result of operation of the ladder or fish trap. FERC has reinitiated consultation with the Service on the proposed action for amending the Jacobson Hydro No.1 Project license. FERC's consultation with the Service on the amendment would determine if fish screens are required to avoid injury or loss of adult, sub-adult and/or larval fish. The proposed action to put the power plant at the dam site would avoid adverse effects of the bypassed river reach compared with the 1990 project; thus there would be no need to require minimum flows to maintain habitat below the dam. However, the licensee would be required to supply about 25 cfs from his power rights to operate the ladder, and power plant tailrace flows would function to attract fish to the entrance of the ladder. Fish Ladder without Hydropower Plant: Concerns for ease of fish use would be similar to those of building a ladder in association with the Jacobson Hydro No.1 Project. Unlike the "with Hydropower Plant" alternative, there would be no harm or loss of endangered fish associated with hydropower plant operation. Dam Removal: Removing a man-made barrier and letting the river channel return to natural conditions would be the most beneficial passage alternative for the endangered fish. If the option to modify the river channel upstream of the dam to maintain the water surface elevation at the Ute Water pump plant is pursued (see page 14), designs for that structure would be reviewed to ensure it does not create new passage problems. This alternative also assumes a fish ladder with selective passage (fish trap) would be installed at the Grand Valley Project Diversion Dam, which is the last remaining barrier to upstream movement. Nonnative fish would thus be prevented from moving further upstream into the critical habitat extending upstream to Rifle. However, dam removal would allow nonnative fish to access Plateau Creek and the 5 miles of the Colorado River upstream to the Grand Valley Project Diversion Dam. 39