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Executive Summary FEIS - Navajo Reservoir Operations 500/6000 Alternative This alternative was considered as a way to reduce potential impacts on downstream water users' ability to take water at their diversion structures by providing a higher minimum flow release of 500 cfs. In addition, it attempts to minimize impacts to downstream recreation (trout fishery and rafting) by maintaining higher minimum releases during certain critical times of the year than does the 250/5000 Alternative. However, it has the same limitations as the 250/6000 Alternative and also does not fully meet the Flow Recommendations. The 6,000-cfs release also exceeds the current safe channel capacity, as discussed under the 250/6000 Alternative. Decommission and Breach Navajo Dam This alternative largely meets the conditions of a natural hydrograph, and removal of the dam would provide the endangered fish with access to the portion of the San Juan River now inundated by Navajo Reservoir, as long as fish passage is provided throughout the river. Although large spring peaks would be provided most years, low flows during the irrigation season would still be occur downstream of diversions, resulting in low flows substantially below 500 cfs within designated critical habitat downstream of Farmington. Therefore, this alternative does not meet the Flow Recommendations. This alternative is considered unreasonable and impractical because it does not meet all the elements of the purpose and need for the proposed action and would not support maintaining the authorized purposes of the Navajo Unit. It would result in loss of reservoir storage needed to allow contract water deliveries to the San Juan-Chama Project, the NIIP, and other contractors, and would make it extraordinarily difficult, if not impossible, for the States of New Mexico and Colorado to fully utilize their consumptive use apportionments under the Upper Colorado River Basin Compact. It also could precipitate expensive litigation of Indian versus non-Indian water rights in both States. In addition, this alternative would result in the loss of the following benefits provided by Navajo Dam and Reservoir: downstream flood control, reservoir and tailwater fisheries, reservoir and downstream recreation, and hydropower generation. The concept of decommissioning or removing the dam is not further considered in the EIS because it does not meet the purpose of and need for the proposed action.