Navajo Reservoir Operations Vol. II

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. RiverWare model representation of the future conditions expected in the San Juan River Basin without implementing flow recommendations is required to establish the "baseline" against which impacts are measured. This condition is called the No Action Alternative and was configured by including all current depletions, all depletions that could occur without further federal action (primarily exercise of state water rights not presently being used as identified by Colorado and New Mexico), and all depletions for which favorable biological opinions did not depend on implementing the action. Since Flow Recommendations would not be met, it was assumed that the ALP Project, completion of blocks 9-11 ofNIIP and 3,000 acre-feet of minor depletions via inter-service ESA consultation would not occur. Depletions used for the No Action Alternative appear in Table I. The model uses operating rules to simulate historic 1973 to 1991 reservoir releases. The reservoir filled in 1973 and in 1991, releases were modified to meet the goal of the 7-year research period (1991-1997). The No Action Alternative depletions total about 667,000 acre-feet per year, including Dolores Project' return flows in McElmo Creek. Configuration for the 250/5000 and 500/5000 Alternatives Model configuration for the two action alternatives is the same, only varying with minimum Navajo Reservoir releases. Minimum target releases are 250 cfs for the 250/5000 Alternative and 500 cfs for the 500/5000 Alternative. To analyze the impacts to hydrology, the model was configured to simulate the future condition of implementing Flow Recommendations and include all current depletions, all depletions that could occur without further Federal action (primarily exercise of State water rights not presently being used as identified by Colorado and New Mexico), and all depletions which have received a favorable biological opinion. These include 57,100 acre-feet per year for the ALP Project, 120,600 acre-feet per year for completion of blocks 9-11 of NIIP, and 3,000 acre-feet per year for minor depletions via inter-service Section 7 consultation. . The configuration of ALP Project was adjusted to address comments from the New Mexico Interstate Stream Commission(NMlSC) to the Draft Supplemental Environmental Impact Statement for the Animas-La Plata Project (DSEIS), Colorado, and New Mexico (Reclamation, 2000). The DSEIS contemplates the Colorado Ute Tribes leasing water under their water rights settlement with Colorado to the San Juan Water Commission in New Mexico. NMISC does not, at this time, support interstate leasing or marketing of water. To meet this request, Colorado Ute Tribes' depletions in New Mexico were moved to Colorado. This was done by moving the diversion point of the gas-fired power plant and the regional water supply for Farmington, Kirtland, and Aztec to Ridges Basin Reservoir. The return flows of the Gas-Fired Power Plant will return to the mouth of the La Plata River and return flows of the Regional Water Supply will return to the Animas River below Basin Creek. The overall configuration of the model before modifications to ALP is shown in Figure A-I. The configuration for the ALP Project modified for Colorado Ute Tribes and New Mexico depletions is included in Figure A- 2. I The Dolores Project, in the Dolores and San Juan River Basins, was devdoped by Reclamation for irrigation, M&l, recreation, and fish and wildlife issues. A-7 00.358