Aspinall Unit operations update: 2150 cfs expected in the Black Canyon

From email from Reclamation (Erik Knight):

Releases from the Aspinall Unit will be increased by 650 cfs between Tuesday and Wednesday, July 9 and 10. This release increase is necessary to prevent Blue Mesa Reservoir from overfilling. At the current release rate it is projected that Blue Mesa Reservoir would spill within 2 weeks. The current forecast for the April-July runoff volume for Blue Mesa Reservoir is 1,060,000 AF of inflow, which is 157% of average. Flows in the lower Gunnison River are currently above the baseflow target of 1500 cfs. River flows are expected to stay above the baseflow target for the foreseeable future.

Pursuant to the Aspinall Unit Operations Record of Decision (ROD), the baseflow target in the lower Gunnison River, as measured at the Whitewater gage, is 1500 cfs for July and August.

Currently, diversions into the Gunnison Tunnel are 850 cfs and flows in the Gunnison River through the Black Canyon are around 1500 cfs. After this release change Gunnison Tunnel diversions will still be 850 cfs and flows in the Gunnison River through the Black Canyon will be around 2150 cfs. Current flow information is obtained from provisional data that may undergo revision subsequent to review.

Black Canyon of the Gunnison

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