Good afternoon,

 

Modifications to HHWP’s July 10 release notification are in bold below.

An emergency outage at Holm Powerhouse will result in reduced flows during the morning of July 13. Releases may increase during the weekend if necessary for managing additional snowmelt runoff in response to forecasted above-average temperatures.

 

We strive to keep the user community updated on projected flows on the Tuolumne River. Flows will continue to vary significantly over the coming weeks as snowmelt runoff progresses and reservoirs are operated at full or nearly full capacities.

 

Stated flow rates are best estimates and are subject to change as conditions and operational constraints evolve.

 

Hetch Hetchy Reservoir

• Total flows below O’Shaughnessy have been reduced to approx. 3,350 cfs on Wednesday July 12^th
• Flows will remain at this rate through the rest of the week, until specified otherwise
• Notifications to be provided as conditions evolve and forecast verification comes in
• Variable releases are anticipated over the next several weeks as Hetch Hetchy Reservoir reaches full capacity
• Kirkwood Powerhouse
• Beginning July 13 at 00:00, spill of approx. 550 cfs will occur around-the-clock

 

Cherry Reservoir

• Total flows below Cherry Reservoir remain at approx. 500 cfs
• Increased valve releases possible over the weekend
• Additional notifications to follow if significant changes are made

• Holm Powerhouse will undergo an emergency maintenance outage on July 13; increased flows are expected otherwise
• Expected outage timing: July 13 05:00 – 10:00 (0 cfs)
• After the outage, approximately 950 cfs flows will be scheduled around-the-clock, until further notice

 

Lake Eleanor

• Valve releases of 600-650 cfs
• Eleanor is not currently spilling; moderate spill rates of 50-200 cfs possible by the weekend

 

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Calculated real time flow station for Meral’s Pool:

https://cdec.water.ca.gov/jspplot/jspPlotServlet.jsp?sensor_no=37334&end=&geom=small&interval=2&cookies=cdec01

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Any significant changes to the schedule will be posted on the bulletin board.