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MAYNES,BRADFORD&SHPS ID:303-247-SS27 FEB 16'96 9:11 No.003 P.06 'I ! Keith Rose and Patty Schrader February IS, 1996 Page S be operated under a variety of scenarios (wet, average, and dry) to mimic a natural hydrograph. However, to date, a dry year scenario has not yet been available. Because of this, all planned research cannot be completed. The objective is to re-create a high spring peak flow providing a gradually ascending limb followed by a gradually declining recession limb to low, stable flows throughout the summer, faI~ and winter. The Service and the biological experts t,,,lic.c. Wn1he!ri7.e that this is may be the best opponunity available to bring the endangered fish back from the brink of extirpation in the San Juan River. The research is deRili'ncd to determine this. By returning the river to a more natural hydrograph and raising the spring peak flows, the Service believes there will be an increase in the reproduction and recruitment of the endangered fish in the San Juan River. The Service believes this operation of Navajo Dam is the most important feature of the reasonable and prudent alternative both for the research period and the long teml. In order for thereto be a permanent annual average depletion of57,100 acre- feet of water from the Project, there must be a guarantee that, ifrcquircd by hll."d un the rcsults of the research program and dependent upon prevailing hydrology, Navajo Dam will be operated to mimic the natural hydrograph for the life oCthe Animas-La Plata Project. Under Section 7(a) J Reclamation has agreed to reoperate Navajo Dam for the recovery of the endangered fishes. Releases for the endangered fish will be legally protected to and through endangered fish habitat to Lake Powell. However, until all research is completed, the required water delivery schedule for II.., lie" uf Navajo Dam (in terms of hydro graph shape, timing, volume, and ti"equency) is unknown. Final year-round flow recommendations will be determined at the conclusion of the research. . . . . The research, therefore, is directed towards detennining how Navajo Reservoir releases can best be used in terms of mimicking the natural hydrograph. This information will be utilized by the Service in coordination with Reclamation to determine reservoir releases needed for the endangered fishes based on the research results and the flow recommendations set fonh in Element 6 The seventh element is legal protection of rclcascs from Navajo Dam and Reservoir to and through endangered fish species habitat. It is not enough to only release water from Navajo Dam There also must be guaranteed delivery