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. . John Turner July 27, 1990 Page 6 service to take all possible steps to find reasonable and prudent alternatives. The first omission is the failure to consider non-flow related mitigation efforts. As you know, non-flow related activities form a critical part of the Recovery Implementation Program For Endangered Fish Species in the Upper Colorado River Basin. That program has allowed further depletions in the upper basin; why were similar alternatives not considered in the San Juan? These could include: (1) improving the water quality of the San Juan River; (2) removing or modifying diversion structures that are barriers to fish movement in the river; (3) modifying the Navajo Dam penstocks to alter water temperature in downstream reaches; (4) purchasing of water rights in, as well as out of, the San Juan River and other basins where the squawfish are found; and (5) initiating controls on exotic fishes including halting the release of popular game species (channel catfish, trout). Viable flow alternatives also exist. The operation of the Navajo Dam and Reservoir can be modified to offset the effective depletion of the project and enhance flows for the benefit of the fish. Hydrology studies by the Bureau of Reclamation demonstrate the availability of water to provide flow levels equivalent to 1987, which were deemed to be good conditions for Colorado squawfish reproduction, on the average of five to six of every ten years. Although the remaining four to five years may not be suitable for spawning, the flow would be sufficient to maintain habitat for juveniles and adults. This pattern is similar to that which existed historically in which the fish did not reproduce in low flow years. While it may not be possible at present to establish specific flows required for the fish, up to ten years of studies could be conducted prior to operation of the Animas-La Plata Project in order to provide the data required to ascertain the flows needed to benefit the fish. Regulating Navajo Dam in such a fashion would protect all existing and planned future development in the San Juan Basin while achieving the Service's objective of utilizing the San Juan Basin to assist in the recovery of the Colorado squawfish.