NAVAJO – In spite of the recent rain storms in the San Juan Basin, forecasters are predicting a continued decline in river flows in the basin for the next week. As a result, Reclamation will be increasing the release from Navajo Reservoir to 800 cubic feet per second (cfs) on Thursday, September 11, 2008, at 4:00 a.m. Releases are made for the authorized purposes of the Navajo Unit, and 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 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, therefore daily flows of less than 500 cfs may occur at some gages.
This scheduled release change is subject to changes in river flows and weather conditions.
Precipitation for the month of August in the San Juan River basin was 90 percent of average. Unregulated inflow into Navajo Reservoir during the month of August was 31,000 acre-feet, or 70 percent of average. The total runoff for the 2008 season ending July (April-July) was recorded at 956,000 acre-feet, or about 122 percent of average runoff. The reservoir had a seasonal peak elevation of 6066.84 feet on May 25, 2008. Navajo Reservoir also provided a spring peak hydrograph of 5,000 cfs during the fist two weeks of May.
Currently the daily reservoir inflow is averaging about 800 cfs and reservoir releases to the San Juan River are set at 700 cfs. NIIP diversions are set at about 300 cfs. The reservoir water surface elevation is currently 6059.76 feet, which corresponds to a storage content of about 1,345,000 acre-feet.To view the most current reservoir elevation, content, inflow and release, click on: Navajo Reservoir Data.
A public meeting on Navajo Reservoir operations was held on Tuesday, August 26, 2008 at 1:00 p.m. in Farmington , New Mexico . At this meeting, review of last spring and summer reservoir operations, and plans for this fall and winter 2008/2009 operations were discussed. These are open forum discussions on the operation of Navajo Reservoir with many interested groups participating. Anyone interested in the general operation of the reservoir is encouraged to attend. Please contact Pat Page in Reclamation's Durango , Colorado Office at (970) 385-6560 for information about these meetings or the daily operation of Navajo Reservoir. To view minutes from the last Navajo Operations Meeting, click on: Meeting Notes.
Paul Davidson
Updated
September 10, 2008
Email comments/inquires to: ResourceMgr@uc.usbr.gov