The new year in California has gotten off to a very wet, rocky start.
Over the last two weeks, the state has experienced an unrelenting and deadly series of storms — or “bomb cyclones” — that have delivered an onslaught of flooding, landslides, fallen trees and power outages, inflicting an estimated billion dollars of damage, and causing at least 19 deaths.
And the barrage isn’t over, as yet another series of storms move in over the weekend.
But there is a silver lining to these so-called atmospheric rivers: They’ve delivered a much-needed resource that our perennially dehydrated state, ironically, needs much more of.
For the last four years, California has experienced a devastating drought that has depleted its reservoirs, forced officials to plead with residents to conserve water and constrained supplies to municipalities and vital farmland. Now, with the snowpack at 174% of the historical average this year — the third-best measurement in the past four decades — Californians could be forgiven for thinking the drought may soon be over.
But while the recent massive dump of precipitation has already helped alleviate drought conditions and replenish reservoirs — with the storms pushing much of the state out of the “extreme drought” category — experts say that positive impact will likely be ephemeral, and fall far short of pulling California out of its protracted state of climate-change fueled drought.
“These storms have not ended the drought,” said Molly White, water operations manager for the State Water Project. Despite the jaw-dropping amount of rain — and in the mountains, snow — that has fallen on the state in recent weeks, she said, “major reservoir storage remains below average, and conditions could turn dry again this winter, offsetting recent rain and snow.”
But some have begun to fill at a rapid pace, especially those near the hard-hit Sacramento region and parts of the Sierra Nevada mountains.
“What we’ve got so far puts us in good shape, probably for at least the next year,” said Alan Haynes, the hydrologist in charge of the California Nevada River Forecast Center.
Snowpack is its own type of reservoir, storing moisture that ideally melts slowly into reservoirs, supplying residents with water during the drier months of summer and fall. But now that snowpack often melts too quickly and reservoirs aren’t able to capture enough of it.
“The California system was built for a climate we don’t have any more,” said Laura Feinstein, who leads work on climate resilience and environment at SPUR, a public policy nonprofit.
Where could the storms fall short?
It’s still early in the winter and it’s unclear what the next few months will bring. Last year, statewide snowpack around this time also looked promising. But a few warm, dry months followed, and when snowpack was supposed to peak in early April, it was just 38% of the historic average.
“We are not out of the drought yet,” said Feinstein.
Plus, the storms haven’t dropped as much water on northern California. The state’s largest reservoir at Lake Shasta that was at 55% of its historical average during the winter holidays had risen to 70% by Tuesday — an improvement, but still well below historical averages due to years of water scarcity, according to Haynes.
The atmospheric rivers aren’t striking everywhere. They move around “like a garden hose if you are spraying it across the yard,” said David Gochis, an expert in how water affects the weather at the National Center for Atmospheric Research in Boulder, Colorado.
“Those biggest reservoirs are just so massive it is probably going to take awhile for them to fill,” he said. For some of the biggest, most crucial reservoirs, it may take take five or six such drenchings, he said.
