Aspinall Unit operations update: 400 CFS in Black Canyon #ColoradoRiver #COriver #aridification

From email from Reclamation (Erik Knight):

Releases from the Aspinall Unit will be decreased from 1350 cfs to 1250 cfs on Monday, September 28th. Releases are being lowered while the Crystal powerplant is offline for maintenance. Diversions into the Gunnison Tunnel have also dropped over the last part of September. The actual April-July runoff volume for Blue Mesa Reservoir came in at 57% of average.

Flows in the lower Gunnison River are currently above the baseflow target of 890 cfs. River flows are expected to stay at levels above the baseflow target after the release change has arrived at the Whitewater gage.

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 890 cfs for September and 790 cfs for October.

Currently, Gunnison Tunnel diversions are 950 cfs and flows in the Gunnison River through the Black Canyon are around 450 cfs. After this release change Gunnison Tunnel diversions will be around 900 cfs and flows in the Gunnison River through the Black Canyon will be near 400 cfs. Current flow information is obtained from provisional data that may undergo revision subsequent to review.

Looking downstream from Chasm View, Painted Wall on right. Photo credit: NPS\Lisa Lynch

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