2011-05-12_PERMIT FILE - M2011028 (2)

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CHAPTER 3 AFFECTED ENVIRONMENT AND ENVIRONMENTAL CONSEQUENCES The new Biological Opinion from the Service supercedes previous Opinions and would be binding on Reclamation. The new opinion, with its associated conservation measures which are adapted by Reclamation, concludes that Refined Alternative 4 would not jeopardize the endangered fish species. The new opinion centers around operation of Navajo Reservoir to mimic a natural hydrograph, operation of the Durango Pumping Plant to bypass spring peaks, and other measures to conserve threatened and endangered species. Conservation measures in the 2000 Biological Opinion include: ? Reclamation will operate Navajo Reservoir to mimic the natural hydrograph of the San Juan River to benefit endangered fish. This will be achieved by following the San Juan River flow recommendations (Holden 1999) and subject to completion of the Navajo Operation EIS and execution of its Record of Decision. ? A RiverWare model is a key tool in analyzing endangered fish flows in the San Juan River. Reclamation, with the Service, will take actions to have an independent review of the model conducted. ? The 1991 Memorandum of Understanding to protect endangered fish releases remains in effect. ? The Durango Pumping Plant will be operated in a manner that facilitates meeting San Juan River flow recommendations. ? Reclamation will implement all actions necessary to prevent escapement of nonnative fish from Ridges Basin and will consider escapement of eggs and larvae in the design. Escapement will be monitored. ? Reclamation will monitor potential bioaccumulation of trace elements in bald eagle food. ? Reclamation will incorporate bypass flows at the Durango Pumping Plant to promote natural recruitments of cottonwood trees. The seven-year research program has been completed and final study reports are being prepared. Flow recommendations to benefit the endangered fish based on this research were made by the SJRBRIP Biology Committee and adopted by the SJRBRIP Coordination Committee. Reclamation has operated Navajo Dam in accordance with the flow recommendation from the SJRBRIP during the research period and continues to follow the recommendations based on the hydrologic conditions to benefit the two endangered fish in the San Juan River. The flows have included both peak flows and low winter flows. Reclamation has completed a study of low winter flows downstream of Navajo Dam. Refined Alternative 4 includes a 120,000 of reservoir at Ridges Basin and annual depletion of not more than 57,100 afy. This depletion meets the requirements of the 1991 and 1996 RPAs. The project includes the commitment to operate Ridges Basin Reservoir with the intent to meet or exceed the flow recommendations for the San Juan River, which should benefit the endangered fish and their critical habitat. Under this alternative there should be no significant impact to either endangered fish species due to flow reductions. This potential impact is considered to be below the level of significance because the offsetting measures have been incorporated into the project design and operation plans. The following mitigation measure, however, would reduce the potential for the impact to occur. /5/.??MAS?l,gGtlc2 e-(LAI- IGt vveerninuche Construction Authority ey-k PIT t-k - PAGE it -Ot'2- 3-119 .7 P.O. BOX AA - TOwaoc, CO 81334 3 SPECIAL STATUS SPECIES