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0 Volume III - Comments and Responses FEIS - Navajo Reservoir Operations Response: In response to the severe drought conditions in the Basin in 2002, Reclamation - informally consulted with the Service to modify reservoir operations. As a result, reservoir releases in 2002 were 60 percent of average releases since 1991. Even though releases in 2002 were the lowest since 1991 (when Reclamation first began operating the reservoir to mimic a - more natural hydrograph), all irrigation, municipal, and industrial users received a full ® supply of water. In effect, the reservoir provided a full water supply during a dry year. The historical conditions that were used to develop the Flow Recommendations did not include 2002 (the driest year on record); however, the resulting modifications in 2002 to reservoir - operations indicate that Navajo Dam operational flexibility in the short term is available during drought conditions depending on storage availability, etc. Additional information regarding flexibility has been included in chapter II of the EIS to address extreme hydrologic conditions. Climatic changes that differ greatly from the historic conditions (1929-93) would have an effect on water availability. However, while suggestions have been made regarding climatic changes, Reclamation cannot predict with certainty when climate changes will happen and to what extent. As a result, Reclamation could not analyze what effects climate changes would have on the Preferred Alternative. General Comment 14: Alternatives should allow for development of New Mexico's and Colorado's compact apportionment water; the EIS implies that only certain future water uses would occur. Response: Meeting the Flow Recommendations is the best way to assist New Mexico and . Colorado to fully develop their compact apportionment. The RiverWare hydrology model - representation of the future conditions expected in the Basin is required to establish the "baseline" against which impacts of alternatives are measured. The depletions associated with the baseline condition include all current depletions, all depletions that are reasonably . likely to occur in the foreseeable future without further Federal action, and all future - depletions for which favorable biological opinions have been issued through the ESA Section 7 consultation process. • The presently defined reservoir operating rules and model configuration do not indicate availability for substantial additional depletions in the Basin associated with implementing the currently proposed Flow Recommendations. Further modification of the operating rules, projected future depletions, and/or improvement in the simulation of the San Juan - River would be required to demonstrate the possibility of further development within the limits of the present Flow Recommendations. Chapter II, "VII. Preferred Alternative," in the FEIS describes provisions for future water development. Also, see General Comment No. 18.