A remarkably wet winter has resulted in some of the deepest snowfalls California has ever recorded, providing significant drought relief and a glimmer of hope for the state’s strained water supply.
Statewide snow fell 190% of normal on Friday, just below a record from the winter of 1982-83, Department of Water Resources officials said during the third snow survey of the season. The surveys are conducted monthly during the winter at Phillips Station near South Lake Tahoe.
In the southern Sierra, snow cover reached 231% of the average for the date, close to the region’s benchmark of 263% set in 1969 and trending before the winter of 1983.
With just a month left in the state’s traditional rainy season, officials are now expressing cautious optimism about the state’s hydrological outlook.
“We have snowpack in California that is near or near record as a result of our snow survey today, with other storms on the horizon and more time left in our traditional rainy season,” said DWR Director Karla Nemeth. “We couldn’t have been luckier with this kind of precipitation after three very hard years of drought and drought.”
California snowpack typically supplies about one-third of California’s water supply, and the past three years have been the driest on record, leading to a statewide drought emergency and unprecedented water restrictions.
“I know the question of the day will be: Does this mean California is officially out of the drought?” and the water supply available to manage for people and the environment,” Nemeth said.
She noted that snow cover in the state is variable and conditions are only average in some parts of Northern California. “It’s still premature to describe that part of the state as being drought-stricken, but it’s definitely great information for Californians,” she said.
In October 2021, Governor Gavin Newsom issued a statewide emergency declaration calling on residents to voluntarily reduce water usage by 15%. In the weeks and months that followed, several regional agencies issued stricter regulations, including mandatory one- and two-day water limits per week for millions of people in Southern California, most of which remain in effect.
Gregory Pierce, co-director of the Luskin Center for Innovation at UCLA, said it probably makes sense to relax some of the most extreme restrictions, but conservation efforts should continue indefinitely.
“This fallout is amazing, and it means we can kind of stop doing some of the most radical things we’ve been doing — and most importantly, we can breathe a little easier for communities that literally ran out of water or on the were about to run out.” out of the water,” Pierce said. “But we cannot stay behind in the field of nature conservation, long-term measures and substantial investments in recycling, large-scale collection of rainwater in groundwater and other technologies.”
“We’ve gained a little more time, so we don’t have to be in that hyper-emergency, but we’re always in a drought,” he added.
Water experts say it will take more than one wet winter to make up for years of shortages, especially when it comes to groundwater. They note that much of the American Southwest is still experiencing its driest two-decade period in more than 1,200 years.
California’s wet winter has sparked renewed calls for improved stormwater harvesting efforts at the local and state levels, with many decrying the amount of water diverted to the ocean during storms. Officials said the need to prepare for floods and droughts at the same time has only gotten worse as climate change leads to weather whiplash, or swings between periods of extreme weather.
In fact, the potential for another atmospheric river storm to develop later in March has raised the specter of flood risk if a warm rain-on-snow event occurs, said Sean De Guzman, manager of snow surveys at the DWR.
“That’s something we’ve been looking at all weekend,” he said. “That storm is generating a lot of interest, but right now it has to be really warm for a lot of that snow to actually melt.”
David Rizzardo, DWR’s department manager of hydrology, said snow at 5,000 feet elevation or lower is more likely to melt, but snow at higher elevations in the Sierra remains extremely cold and won’t melt quickly. Officials are already preparing for when the abundant snow comes down at those higher elevations, he said.
“It’s really at this point, when the weather will change to the point where we go from building a snowpack to a melting snowpack,” he said.
He and other DWR officials said many reservoirs — while much healthier after the winter storms — still have some room to fill. Lake Shasta, the state’s largest reservoir, had a capacity of 61% as of Friday, according to state data.
Still, there’s no denying that the record winter has put a dent in the drought. The U.S. Drought Monitor cleared more than half of the state from four categories of drought on Thursday, including about 34% of California now classified as “abnormally dry” and 17% as completely out of drought.
In February Newsom an executive order issued instructing government agencies to assess the current drought response and make recommendations, “including potentially even ending specific emergency services that are no longer needed,” De Guzman said. “But that won’t really be until we have more clarity on what the hydrologic conditions are for the year as we approach April.”
Officials also continued to stress that groundwater has been depleted by climate change and overpumping, including some basins that could take years, decades or even longer to refill.
“We have areas like the Central Valley and the San Joaquin Valley in particular – where there is really just a massive shortage of groundwater basin storage over a long period of time – and this is not something that is going to change any time soon,” says DWR drought manager Jeanine Jones.
Pierce, of UCLA, noted that the Colorado River — an important source of water for Southern California — also remains dangerously depleted. And with long-term trends still pointing to a hotter, drier California, now is not the time to “let go of the pedal,” he said.
“We absolutely cannot give up on the medium and long term (efforts) because this is going to be an abnormally positive year,” he said. “And who knows what the next 5 to 10 years will bring. We could be right back in the same situation we were in two months ago and two years ago.