Is Lake Shasta's Water Level Rising?

As relentless rain continues to batter the Golden State, water levels in California's drought-stricken reservoirs appear to be on the rise. The state's largest reservoir, Lake Shasta, received over 13 inches of rain in the first 11 days of 2023, but its water levels are still below what they usually are at this time of year.

"We've had three consecutive years of drought, probably one of the worst droughts California has ever experienced," Ernest Conant, regional director of the California branch of the U.S. Bureau for Reclamation, told Newsweek.

"At the beginning of this water year, which is October 1, 2022, the lake was a third full, at 33 percent. We're now at 42 percent and climbing. We're gaining ground, but we still have a long way to go," Conant said.

Donald Bader, the Shasta area manager for the Bureau of Reclamation, said that despite the 13 inches of rain that have fallen on Lake Shasta since the start of January, the lake's water level is still below average.

"Right now, we're at about 80 percent of what we normally would be on today's date," he said. "We were in the 60s before, on historic average, so we're trending in the right direction, but what concerns us all the time is that the weather can change on a dime," Bader said.

There were many storms in October and December last year, Conant said, but this was not enough to restore the reservoir's water levels. "It just stopped raining in January, February and March, and we had the lowest precipitation ever on record for those three months. That's why we were in such a dire situation this past year."

Jeff Mount, a senior fellow at the Public Policy Institute of California's Water Policy Center, explained why Lake Shasta is so crucial. "Shasta...plays a crucial role in supplying water to the federally managed Central Valley Project, which supplies water to cities and farms throughout the Central Valley. Shasta also provides flood control and hydropower," he said.

Shasta is the largest of several reservoirs that make up the Central Valley Project, which is run by the U.S. Bureau of Reclamation. "We supply water to about 3 million acres of some of the most productive farmland in the state, and we supply water to municipal suppliers that provide water to about 6 million Californians," Conant said. "In addition, we supply water to 19 wildlife refuges throughout the Central Valley."

The individual reservoirs within the project—which also includes Trinity Lake, New Melones, Folsom and San Luis—act as backups if one area receives less rainfall than another.

Water levels in Lake Shasta have risen by 47 feet since the start of the year, and snowfall in the mountains as a result of the precipitation is also a promising sign.

"The major Sierra mountains on the eastern side of the Central Valley are at 200 percent of average snowpack, which is great because that will come down later in the spring when it starts warming up," Bader said. "So we can anticipate that and add that to our storage volumes because we know we've got that extra storage sitting up there in the mountains. There's a tremendous amount of snow this year, so that's very encouraging."

Graham Fogg, a professor emeritus of hydrogeology at the University of California, Davies, said that although the recent rainfall has been beneficial, it is not enough to fully compensate for the drought.

"The lake is still below the average storage for this time of year by about 0.8 million acre-feet," he said. "If the snowpack continues to accumulate and the next 15 or so weeks are not too warm, the April-July snowmelt period will definitely help partially refill Shasta. [But] it would likely take at least a couple more years of average-to-wet years for California to more fully climb out of the drought."

Although the recent rainfall is promising, Bader said, the Bureau of Reclamation would not be able to confidently say if there has been enough rain to restore water levels in Lake Shasta until February, after another month of potentially wet weather.

"If [conditions] continue as is, Shasta is going to be in good shape," he said. "But if they dry up, we're going to be below normal, and that's going to have an impact on the entire state.

"Right now, we're just really hoping the rains continue because we've seen it too many times where they just shut off," he said.

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