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Executive Summary FEIS - Navajo Reservoir Operations 250/5000 Alternative Operations under this alternative would best meet the purpose of and need for the proposed action. It would support water projects that have completed ESA consultations and NEPA compliance-including NIIP completion, the ALP Project (ALP Project), the Jicarilla Apache contract with Public Service of New Mexico, the Jicarilla Apache Nation Navajo River Water Storage Project, and 3,000 acre-feet for minor unspecified depletions-to proceed, and would meet the Flow Recommendations. Since this alternative meets Flow Recommendations, it also removes the risk of impact to the other water uses listed under the No Action Alternative. Reclamation would modify Navajo Dam operations to provide sufficient releases of water at times, quantities, and durations necessary to assist in conserving endangered fish and their designated critical habitat. Reclamation would maintain the authorized purposes of the Navajo Unit, enabling water development with ESA compliance to occur in compliance with applicable laws, compacts, decrees, and Indian trust responsibilities. Under this alternative, releases would range from 250 cfs to 5,000 cfs. The spring peak release would meet the Flow Recommendations criteria. Non-spring peak releases as low as 250 cfs are intended to meet the Flow Recommendations downstream of Farmington and to provide water storage in Navajo Reservoir. These releases would also help maintain a minimum 500 cfs flow downstream of Farmington, benefitting river rafting in dry years. 12 All releases would be made within the operational limitations/ constraints of Navajo Dam. " The target base flow is calculated as the weekly average of gaged flows throughout the critical habitat area; therefore, daily flows of less than 500 cfs may occur at some gages. The goal of the Flow Recommendations is to maintain San Juan River base flows downstream from the Animas River confluence at Farmington between 500 and 1,000 cfs. Because of variable inflows from the Animas River, occasional high inflow from intermittent tributaries, diversions, and return flow, and water travel time from Navajo Dam, this goal is difficult to consistently meet. The Flow Recommendations call for using a 7-day moving average of two of the four downstream gages to monitor whether flows are kept between 500 and 1,000 cfs. This monitoring plan was presented in the DEIS. There can be significant variability in these gage readings and the selective use of any two gages could give results above or below the intent of the Flow Recommendations. Because of this, in 2002 the SJRBRIP suggested that flows be monitored by the following: "Use the lesser of the average of Bluff, Four Corners, and Shiprock (gages) and the average of Farmington, Shiprock, and Four Corners (gages)...extreme conditions (low or high flows) identified by...Reclamation will be handled on a case-by-case basis with recommendations of the Biology Committee." The Service has provided written support of this approach to monitoring. Reclamation's intent, documented in the FEIS, will be to maintain the recommended base flows in the critical habitat reaches by using the best available gage information. In practice, Reclamation and the Service will discuss flows routinely during the irrigation season and (as needed) the remainder of the year to determine the operations needed to meet the base flows. Reclamation, in consultation with the Service, will use the lesser of the weekly moving average of the Bluff, Four Corners, and Shiprock gages and the average of the Farmington, Shiprock, and Four Comers gages as the guide in meeting this intent. In periods of severe drought, Reclamation will work with the Service to arrive at operating criteria to respond to these conditions. For example, in 2002, Reclamation and the Service agreed to reduce target base flows in the critical habitat reaches to 350 cfs due to the extreme drought conditions.