California Reservoir Dam Release Update as Water Levels Stall

Officials have stopped water releases at the Lake Oroville dam as of Wednesday morning following nearly a week of outflow that equated to billions of gallons of water leaving the lake.

California's Department of Water Resources (DWR) opened the main spillway at Oroville Dam last Wednesday to provide flood protection for downstream communities in advance of two atmospheric rivers that were set to batter the state with torrential rain. Lake Oroville's water levels had jumped significantly in advance of the storms, but the storms have since passed and Lake Oroville's water release through the main spillway has now stopped.

A DWR spokesperson told Newsweek an estimated 62,122 acre-feet of water were released through the spillway while it was open.

"Water releases from Oroville Dam's main spillway will stop around 10 a.m. with releases continuing through the Hyatt Powerplant," the DWR posted on X, formerly Twitter, on Wednesday morning with a photo of the dam. "DWR is reducing Feather River releases due to low runoff inflow rates into Lake Oroville. Lake Oroville is currently at 77 percent of storage capacity."

The lake rose by 15 feet in the last two weeks of January, but since the release began last week, the levels have since stalled around 842 feet. The lake is 56 feet below full pool, a much-improved state over the summer of 2022, when the lake reached concerningly low levels. The lake is 28 feet higher than it was this time last year, and 97 feet higher than it was in February 2022.

In a follow-up post, the DWR said that water released into the Feather River supports the environment, with some of the water flowing downstream to the San Luis Reservoir, "where it is captured to maintain overall water supply."

A similar release occurred at Pyramid Dam on Monday when water officials chose to release excess stormwater associated with the atmospheric river.

The water released from Pyramid Dam also was captured for future water supply.

"The intense storms in Southern CA prompted DWR to release excess stormwater through the gated spillway at Pyramid Dam today in LA County," the department posted on X with a photo of the release. "The water will be captured & stored downstream by @UnitedWaterCD in Lake Piru for future water supply to benefit communities in the region."

Oroville Dam spillway releases could increase in the future, but the DWR spokesperson told Newsweek the decision to open the spillway was "entirely weather dependent."

"DWR continues to monitor lake levels, weather forecasts and mountain snow levels to optimize water storage at Lake Oroville and meet environmental requirements while allowing for carryover storage into next year," the spokesperson said.

Lake Shasta, also in Northern California, has risen significantly since the beginning of the year, and water officials also are managing Lake Shasta to mitigate flood risk.

U.S. Bureau of Reclamation spokesperson Mary Lee Garrison-Knecht previously told Newsweek that as of last week, the USBR has increased releases "at Shasta and its regulating reservoir...for storage management."

Update 2/8/24, 10:09 a.m. ET: This story was updated with comments from the California Department of Water Resources.