Tuolumne River Flow Info May 23 – 29

A message from Hetch Hetchy Water and Power regarding flows on the Tuolumne and Cherry Creek from May 23 – May 29.

Hello Recreationists -

Between the cooler weather and melt out of the snowpack in the Eleanor basin, the spill at Eleanor that has been helping to support recreation for the last 10 days is coming to an end. There will be normal releases for fisheries below HHWP facilities after Saturday. The Middle and South Forks have also decreased, and inflows there are probably about 100 cfs.

As scheduled on the recreational release calendar, daily releases will be produced by Holm PH from today (Friday) through Monday that will create flows of 1100 cfs or more at Lumsden from 9 am to 1
pm.

On Tuesday, May 27, an ecological pulse flow will begin at Hetch Hetchy, and the release from O’Shaughnessy Dam will ramp up to 200 cfs by the end of the day. On Wednesday, the release will go from about 1800 cfs to about 3600 cfs at 8 am, and then up to 6200 cfs from 1 pm to 5 pm. The release will then ramp back down, reaching the normal release of 80+ cfs by noon on Thursday the 29th.

These higher releases take about 6 hours to reach Lumsden, so the 3600 cfs flow will reach Lumsden between 1 and 3 pm. Please use caution and boat safely if you plan to launch during these higher
flows on Wednesday. If you are camping downriver Wednesday night, remember to pull your craft way up the bank and do rope it down so it is still there Thursday morning. The highest flow could arrive, depending on where you are, after dark.

Best holiday wishes to all.