Navajo Reservoir – The current (February 11th) daily average release rate from Navajo Dam is 283 cfs and the observed inflow to Navajo Reservoir is 159 cfs. The reservoir elevation is 6015.03 feet which corresponds to a live storage of 0.866 maf (51 percent of live storage capacity). This elevation also corresponds to an active storage of 0.206 maf (20 percent of active storage capacity). The river flow measured at the San Juan River at Four Corners USGS gage is 494 cfs. River flow at the Animas River at Farmington USGS gage is at 224 cfs. Releases from Navajo Dam are made for the authorized purposes of the Navajo Unit, and pursuant to the 2006 Record of Decision, to attempt to maintain a target base flow through the endangered fish critical habitat reach of the San Juan River (Farmington to Lake Powell). The San Juan River Basin Recovery Implementation Program (SJRIP) recommends a target base flow of between 500 cfs and 1,000 cfs through the critical habitat area. The target base flow is calculated as the weekly average of gaged flows throughout the critical habitat area.
Preliminary modified-unregulated inflow into Navajo (inflow adjusted for upstream change in storage, reservoir evaporation and exportation from the basin) in January was 13,177 af (60 percent of average). SNOTEL sites above Navajo are at 92% of average with 12.3 inches of SWE.
Forecast modified-unregulated inflow to Navajo over the next three months (February, March, and April) are projected to be: 15,000 af (50 percent of average), 40,000 af (43 percent of average), and 78,000 af (46 percent of average), respectively.
The April through July runoff forecasts are as follows:
Min Probable: 275,000 af (37 percent of average)
Most Probable: 430,000 af (58 percent of average)
Max Probable: 750,000 af (102 percent of average)
The winter release will target the minimum baseflow in the critical habitat reach and may be reduced to as low as the minimum release of 250 cfs, so long as the target baseflow downstream is still met. Releases will remain as low as possible over the winter in an effort to conserve water in the reservoir.
Based on current storage and long-term projections, Navajo has a 15% chance of filling to at least 6050 ft and a 5% chance of filling to at least 6060 ft in the spring of 2019. Based on current projections there are no plans for a spring peak release, though a short-duration maintenance release is under consideration.
Reclamation conducts Public Operations Meetings three times per year to gather input for determining upcoming operations for Navajo Reservoir. Input from individuals, organizations, and agencies along with other factors such as weather, water rights, endangered species requirements, flood control, hydro power, recreation, fish and wildlife management, and reservoir levels, will be considered in the development of these reservoir operation plans. In addition, the meetings are used to coordinate activities and exchange information among agencies, water users, and other interested parties concerning the San Juan River and Navajo Reservoir.
The next Navajo Public Operations Coordination Meeting is scheduled for Tuesday, April 23rd, 2019, at 1:00 p.m. at the Farmington Civic Center, Farmington, NM.
Please contact the Operations Group via e-mail at ResourceMgr@usbr.gov for additional information.
Last Updated: 2/12/19