Aspinall Project Notices

Project Notices

BUREAU OF RECLAMATION
ASPINALL UNIT RELEASES
July 22, 2021

April – July unregulated inflow volume to Blue Mesa Reservoir 

Current Forecast (July 15) = 305,000 AF (45% of average) 

 Blue Mesa Reservoir current conditions 

Content = 357,000 AF (44% full) 

Elevation = 7458.4 ft 

Inflow = 700 cfs 

  Crystal Release = 1675 cfs 

Gunnison Tunnel diversion = 1040 cfs 

Gunnison River flow = 660 cfs 

 Spring Operations Summary 

Aspinall Unit Operations ROD 

 Hydrologic Category = Dry 

Peak Flow = 1900 cfs 

Duration at Peak Flow = 1 day 

 Baseflow Target: August/September = 890 cfs (Point of measurement is the Gunnison River near Grand Junction streamgage, commonly called the Gunnison River at Whitewater) 

 Black Canyon Water Right 

 Peak Flow = 1025 cfs (24 hour duration) 

Shoulder Flow Target = 300 cfs (May 1 – July 25) (Point of measurement is the Gunnison River below Gunnison Tunnel streamgage at the upstream boundary of Black Canyon of the Gunnison National Park) 

 Projected Operations  

Gunnison River flows (Black Canyon/Gunnison Gorge)  

• Currently around 660 cfs, expected to remain near 660 cfs for the remainder of July 
• In August, September and October of 2021, average daily releases are scheduled to be maintained at current levels in response to a continual declining dry hydrologic condition for the Colorado River system.  This drought operation is implemented under the Upper Basin Drought Response Operations Agreement (DROA).  Without DROA operations, releases were expected to decrease in late summer/early fall so this continued level of release will deliver additional water to Lake Powell as described in the following press release.  https://www.usbr.gov/newsroom/#/news-release/3917 

 Blue Mesa Reservoir maximum fill = 394,000 AF at 7465 ft elevation 

Projected Blue Mesa Reservoir conditions on Dec 31 = 192,000 AF at 7425.5 ft elevation  

This scheduled release change is subject to changes in river flows and weather conditions. For questions or concerns regarding these operations contact

Erik Knight at (970) 248-0629, e-mail eknight@usbr.gov

Ryan Christianson at (970) 248-0652, email rchristianson@usbr.gov

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Contact

Please contact the Operations Group via e-mail at ResourceMgr@usbr.gov for additional information.