Aspinall Unit operations update: Gunnison Tunnel diversions = 950 cfs, Gunnison River through the Black Canyon = 2550 cfs

Gunnison Tunnel via the National Park Service

From email from Reclamation (Ryan Christianson):

Releases from the Aspinall Unit were increased by 500 cfs beginning on Friday, July 26th and are scheduled to continue at that rate into the near future in order to prevent Blue Mesa Reservoir from overfilling. At the current inflow and release rate it is projected that Blue Mesa Reservoir would begin spilling, as the reservoir is now full. The current forecast for the April-July runoff volume for Blue Mesa Reservoir is 1,075,000 AF of inflow, which is 159% 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 950 cfs and flows in the Gunnison River through the Black Canyon are around 2550 cfs. Current flow information is obtained from provisional data that may undergo revision subsequent to review.

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