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2. Solutions (recommendations] to providing passage around, through, or over the barrier. If a fishway is an option, the type(s) of fish passageway structure(s) that could be used to provide the greatest likelihood of allowing or maintaining undisrupted movement around, through, or over the barrier 3. Biological benefits to the population by providing upstream fish passage 4. Potential biological problems to the population by providing upstream fish passage Barrier Type: Low Item 1. Consequences: Obstruction of upstream movement during seasonal, low-flow periods 2. Solution: 1) It is recommended that adequate flows be established that would enable fish to pass upstream during these periods when a low-head diversion could not be negotiated. This would require purchasing water rights that would provide adequate flows during these low- flow periods. For instance, at Tusher Wash Diversion, adequate flows to enable fish to negotiate the fishway could be stipulated as a conservation measure that could be encorporated into the Flaming Gorge Biological Opinion. A confirmed spawning area is about 20 miles upstream of Tusher Wash Diversion. Adult squawfish that originate downstream of the Diversion have successfully passed over this structure. During extreme low water periods, it is not known if sub-adult or adult squawfish are capable of negotiating upstream passage of this structure. Maintaining passage by this barrier may be essential for squawfish, either for moving to upstream spawning areas or for use of different upstream habitats. 2) A fish passage facility is not a practical recommendation because the initial cost and annual maintenance of such a structure would outweigh its use. The cost of purchasing water rights would probably be less expensive in the long run than the cost and maintenance of a fish passageway. 3) If fish passageway is a consideration at low-head structures, it could be operational and available for squawfish to use during moderate and high flows, save extremely low-flow periods. Depending on the nature of the water year and amount of water diverted for irrigation use, there would be situations where the fish passageway would be the only means fish could gain upstream access. During extreme periods of low flow, it should be expected that there may not be enough water to keep the fish passageway operational. 3. Biological benefits using a fish passageway: 1) Increased knowledge of whether Colorado squawfish will negotiate a 11