Is California Still in a Drought?

California and other Western U.S. states were scorched by drought for much of 2022, with an overarching megadrought having had its grip on the West for over 20 years. And despite storms and torrential rain lashing the Golden State this past week, causing huge floods, the massive downpours have done little to change the overall picture in California.

In July, one-third of the total area of California, plus Texas, Oregon, Nevada, Utah and New Mexico, was considered to be enduring "extreme" or "exceptional" drought, the U.S. Drought Monitor found. As of January 5, 2023, 100 percent of the state of California was experiencing some degree of drought conditions, with 71 percent being under "severe" to "extreme drought"—even with all that rain.

This blisteringly dry weather last year drastically lowered water levels in reservoirs and other bodies of water across the state, including several important sources of water for millions of people in towns and cities, and in agriculture.

Lake Shasta, the largest reservoir in California, is situated around 170 miles north of Sacramento. This summer, Shasta's water levels dropped from a maximum of 947 feet above sea level in May to a low of 917 feet in November. In November 2020, Shasta's water levels were much higher, around 960 feet.

"In California we're in a multi-year drought," Roger Bales, a distinguished professor of engineering at UC Merced and adjunct professor at UC Berkeley, previously told Newsweek.

"We have some level of resilience for shorter droughts, one year or two," he said. "Our climate here in the West is a mix of wet & dry years, and we have both natural and built multi-year storage. But this storage can only provide water for so long."

"Think of having a reserve in your bank account. If your income dropped in one paycheck period, you could draw upon the reserve to continue spending at the same level. But if your income dropped in several periods, you would need to reduce expenses to keep things in balance. The problem comes when we have multiple dry years in a row."

Lake Mead, a reservoir of the Colorado River on the border of Arizona and Nevada, provides water to 25 million people in California, Nevada and Arizona. In 2022, Lake Mead dropped to the lowest water levels seen since it was created in 1935. As of July 18, it was filled to just 27 percent of its full capacity.

"It's hard to know [what] future conditions might bring, but the Bureau of Reclamation produces estimates up to five years in the future, which show the Lake Mead levels are likely to further decrease (about 30 feet) in the next two years. It's important to note that there's a lot of uncertainty in these estimates," Antonia Hadjimichael, an assistant professor in geosciences at Penn State University, previously told Newsweek.

The downpour drenching central and northern California this week may be helping to restore the water levels of many lakes in the wake of the blisteringly hot summer. Northern California has experienced unprecedented rainfall due to a storm this week, with San Francisco seeing 5.46 inches of rain falling in a single day on December 31, and Sacramento suffering flooding.

On December 27, 2022, Shasta's water levels were at 910.44 feet above sea level—as of January 5, 2023, it had risen to 932.04 feet. Additionally, between December 27, 2022, and January 3, 2023, Lake Oroville saw a water level rise from 676.54 feet above sea level to 713.56 feet.

"This next system that moves through is going to hit Shasta hard," Don Bader, area manager of the U.S. Bureau of Reclamation, told Redding Record Searchlight. "We're probably looking at 40 or 50 feet of the lake coming up."

As of January 3, Lake Shasta was at 34 percent capacity, which is 57 percent of the usual water level at this time of year.

Climate change is expected to only worsen the effects of drought on the water levels of water bodies: between 2000 and 2021, 42 percent of soil moisture deficit was attributable to climate change, according to a study published in the journal Nature Climate Change last year.

Auroop Ganguly, director of the Sustainability and Data Sciences Laboratory at Northeastern University, Boston, previously told Newsweek, "On the hydrometeorological hazards side, heat waves are getting—and are further projected to get—even hotter, cold snaps persisting even if growing less frequent, heavy precipitation getting heavier, and so on."

Droughts will get drier, but the rainfall will likely get heavier, so scientists are unsure of the exact outcomes that these climate changes will have in the coming years.

"Most recent estimates using regional climate models are seeing intensification of droughts across the U.S., especially in regions in the Midwest, Northwest and California," Hadjimichael said. "Again, important to note here that there's a lot of uncertainty and our ability to predict droughts is also diminished under a changing climate, as things become more variable or physical processes change, like declining snowpack."

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