Millerton Lake is at capacity, allowing officials to prepare for spilling by making sure equipment at Friant Dam is working properly.
The gates atop the dam’s spillway were tested Tuesday morning to ensure they function ahead of any major spilling due to overflow.
“This equipment can only be tested when the reservoir is full, so we took the opportunity,” said Duane Stroup, deputy area manager at the U.S. Bureau of Reclamation.
Stroup said inflow to the reservoir is higher than the demand. As a result, water is being released into the San Joaquin River – but not through the spillway.
The water release is being controlled through outlets at the base of the dam, Stroup said. The releases from the outlets were between 1,000 to 1,750 cubic feet per second as of Tuesday. The reservoir’s capacity is 520,000 acre-feet.
Even as snow melt continues to flow into the reservoir, the plan is to keep Millerton full as long as possible, according to Stroup.
There is danger as lakes begin sending water downstream into rivers. This summer some rivers were closed (and subsequently reopened) to recreational use due to high water levels.
Locally, the San Joaquin River has not faced closures or seen drownings this year.