Aspinall Unit Reservoirs

Blue Mesa Reservoir

Current Status

Last Updated: October 14, 2021

Aspinall Unit Reservoirs – As of October 11, 2021 releases from Crystal Dam are approximately 1050 cfs. Gunnison Tunnel diversions are occurring and are currently about 680 cfs.  Flows of the Gunnison River in the Black Canyon are being maintained at about 330 cfs.    

The unregulated inflow volume in September to Blue Mesa was 18,867 af (51 percent of average). Unregulated Inflow volumes forecasted for Blue Mesa for the next three months (October, November and December) are projected to be: 24,000 af (65 percent of average), 22,000 af (73 percent of average) and 19,000 af (76 percent of average), respectively. The October 24-Month Study is reflective of these new forecasts. 

The 2022 water year unregulated inflow volume is projected to be 760,000 af (84 percent of average).  The water supply period (April-July) for 2022 is projected to be 550,000 af of unregulated inflow (86 percent of average). 

In August, September and part of October, releases were increased as a response to a continual declining dry hydrologic condition for the Colorado River system.  This drought operation was implemented under the Upper Basin Drought Response Operations Agreement.  The maximum flexibility within the Aspinall Record of Decision was utilized under this drought operation to release 36.11 kaf more than what would have been released under normal operations for the hydrology that occurred during the period.  The intent of this operation was to support Lake Powell to maintain hydropower operations. 

Under the Aspinall Record of Decision (2012), base flow minimum targets flows, measured in the Whitewater Reach of the Gunnison River, are established for 6 categories of hydrological conditions.  The category for this year is the dry category.  The baseflow minimum target flow for dry category years during the months of August through March is 750 cfs in the Whitewater Reach.  Flows in the Whitewater Reach are approximately 1230 cfs.

Blue Mesa will not fill in water year 2021.  Blue Mesa reached a peak elevation of 7,464.28 feet on June 22, 2021. The elevation is now declining and is projected to reach a minimum elevation of about 7428 feet on or about November 1, 2021.  This will be down approximately 91 feet from the full pool elevation (7,519.4 feet) and water storage in Blue Mesa at this time will be approximately 204,000 acre-feet which is 25 percent of live capacity.

The Aspinall Unit Operations Group is an open public forum for information exchange between Reclamation and the stakeholders of the Aspinall Unit. The public is encouraged to attend and comments on the operations and plans presented by Reclamation at these meetings. Meeting notes from past working Group meetings are posted on the Operations Group webpage. For more information on this group and these meetings please contact Erik Knight in the Grand Junction Area Office at (970) 248-0629.

The next Operations Group meeting will be held in January, 2022.  The meeting may be virtual or in person and a decision has not yet been made.  Contact Erik Knight in the Grand Junction Area Office at (970) 248-0629 to get more information regarding this Operation Group meeting.

Updated 10/12/2021
Rick Clayton
Aspinall Operations

To view the most current reservoir elevation, content, inflow and release, click on: Blue Mesa Reservoir Data or Crystal Reservoir Data.


Please contact the Operations Group via e-mail at for additional information.

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Last Updated: 10/14/21