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Volume III - Comments and Responses FEIS - Navajo Reservoir Operations No Action and the 500/5000 Alternatives are 481,716 and 615,401 acre-feet per year (afy), respectively. This is a difference of 133,685 afy of depletion. Total Colorado depletions for the No Action and the 500/5000 Alternatives are 174,557 and 218,088 afy, respectively. This is a difference of 43,531 afy of depletion. The difference between the total annual depletions (675,423 and 852,639 acre-feet, respectively) of these two alternatives is approximately 177,216 afy. General Comment 5: A wider range of alternatives should have been considered: (a) The DEIS does not present all feasible alternatives. An alternative that avoids flows that are too high or too low is needed to reduce adverse impacts. Further analysis using minimum releases ranging from 300 to 450 cfs should be completed prior to decisionmaking. Response: The alternatives analyzed in the DEIS are intended to reflect minimum and maximum flow release parameters. Such parameters would provide Reclamation with flexibility to regulate releases from 250 cfs minimum to 5,000 cfs maximum in consultation with the U.S. Fish and Wildlife Service (Service), depending on variables inherent in the operation of Navajo Dam. During planning for the EIS, various minimum flows were hydrologically modeled. The results showed that only the 250 cfs minimum release allowed for the Flow Recommendations and Navajo Unit authorized purposes to be met. (b) An alternative with a minimum flow of 500 cfs (reduced during severe droughts and possibly winter months) should be considered, and the 250 Variable/5000 Alternative needs to be given full consideration. Response: An alternative with a minimum flow of 500 cfs was considered and analyzed under the 500/5000 Alternative. The 250 Variable/5000 Alternative was originally intended to be analyzed as a reasonable alternative to the Flow Recommendations (250/5000 Preferred Alternative), but was subsequently dropped from further consideration for reasons discussed in General Comment No. 4. (c) Has the Bureau considered any alternatives that are outside its jurisdiction? Response: Alternatives are designed to meet specified needs. However, the "need" identified in the EIS includes constraints that require Reclamation to establish operating criteria for the Navajo Unit to accommodate ESA-related requirements and, at the same time, to accomplish the purposes of the Navajo Unit within the agency's jurisdiction. Accordingly, all alternatives considered in detail in the EIS were designed to meet this need. Some alternatives (such as decommissioning Navajo Dam) that are outside the agency's jurisdiction were considered but eliminated.