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I Control Act (P.L. 93-320 Operations After completion of the Navajo Unit in December 1963, the focus of the criteria for releasing water from the dam was primarily on meeting irrigation needs, providing flood control, maintaining stable flows, and providing a recreation pool in Navajo Reservoir, However, over the last decade, the focus of the criteria and associated pattern for releasing water from the Unit has changed, The effects that Navajo Reservoir operations have had on native endangered fishes and trout have resulted in various commitments by Reclamation to evaluate operations and consider implementing release rules to benefit endangered fish, in consideration of the effects on the trout fishery and other downstream resources, The catalyst for entering formal consultation under Section 7 of the Endangered Species Act (ESA) for operations of Navajo Dam was the proposed construction of the Animas-La Plata Project (ALP), On May 7,1990, the U,S, Fish and Wildlife Service (Service) issued a biological opinion concluding that the ALP Project would jeopardize the continued existence of the Colorado pikeminnow, but no reasonable and prudent alternative (RPA) was identified at the time, New hydrological investigations suggested that additional flexibility which existed in the operation of Navajo Dam could help offset the negative impacts of constructing ALP, For example, reducing late fall and winter releases could make water available to increase spring peaks and return the San Juan River to a more natural hydrograph that would mimic pre-dam historic flow conditions, This flexibility in flow patterns would assist in developing an RP A for implementation of ALP, and result in protecting the Colorado pikeminnow as ALP construction proceeded, Formal consultation on the operations of Navajo Dam was requested by Reclamation in a July 30, 1991, memorandum to the Service, In that memorandum, Reclamation committed to operate Navajo Dam in concert with ongoing research to determine hydrologic conditions for the fish and to operate Navajo Dam in a manner most consistent with endangered fish recovery, for the life of Navajo Dam, lt was also recognized that Reclamation would produce the necessary documents to comply with NEPA on any recommended changes to the operating criteria for Navajo DanL In it's August 19, 1991, memorandum responding to Reclamation, the Service concurred with Reclamation's request that the consultation process be initiated and that the overall consultation period for the operations of the dam be extended while planned research on the San Juan River was conducted, In subsequent Section 7 consultation on the ALP, an RPA was was included in the October 25, 1991 Biological Opinion that incorporated the earlier commitment by Reclamation to operate Navajo Dam so as to mimic the natural hydrograph, for the life of the ALP Project. Since the specifics of how to mimic a natural hydrograph were not quantified for the San Juan River, the RP A included a commitment to contribute funding for approximately seven years of research, under the Draft May 15,2000 4 Plan of Approach for Navajo Dam Operations EIS [;1')"8 j, ,", -- ~- .....