Photograph by Peter Essick, Nat Geo Image Collection
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California's Sierra Nevada mountains are a key source of much of the state's water.

Photograph by Peter Essick, Nat Geo Image Collection

Snowpack 97% of Average in California's Northern Sierra

New spring survey shows some drought relief but more conservation is needed to ensure adequate water supply. 

California's five-year drought isn't over yet, but the state's snowpack now stands at 97 percent of its historical average, according to a measurement taken today in the Sierra Nevada.

A year ago, Governor Jerry Brown stood at the same monitoring point and didn't see a single snowflake. The snowpack was just 5 percent of average then, the lowest ever recorded, prompting him to declare a statewide emergency and order urban areas to slash water use by 25 percent.  

Today's measurement is considered the year's most important because it comes at the time of maximum snow depth. In normal years, California gets about 30 percent of its water supply from the Sierra Nevada snowpack, which melts gradually, releasing water down rivers and into reservoirs at the time of the year when it is needed most by residents.  

Thanks largely to winter storms spurred by El Niño, the monitoring point in the northern Sierra, known as the Phillips Station, was covered Wednesday with 58.4 inches of snow. That snow held 26 inches of water content, which is 97 percent of the historical average for March 30, according to the California Department of Water Resources.

The new measurement is a single reading at one station east of Sacramento, but it is "a good sign for water suppliers and for California's agricultural community, who have been dealing with almost no deliveries from the state water project for the last few years," says Matthew Heberger, a researcher at the water-focused Pacific Institute in Oakland. 

"It shows that our outlook is better but it doesn't necessarily mean that we're out of the woods or that the drought is over," says Heberger. (Learn more about the drought crisis.)

For one thing, the statewide snowpack's water content remains below average, estimated at 87 percent of the April 1 historical average

The state's largest reservoir, Lake Shasta, has risen 134 feet since December and stands at 87 percent of its capacity

The state has lost so much water over the past several years that it will take more than this season to refill aquifers and reservoirs, a fact that may prompt additional conservation measures. Further, the state is expected to see a rising population—and therefore more water demand—as well as increased climate uncertainty in the future.

"Droughts are likely to become more frequent and severe in the future so we have to learn to do more with less water," says Heberger. 

Since the governor imposed mandatory cuts in water use last year, Californians have largely followed through, cutting usage 24.8 percent. It's a first step, but there's a lot more potential for further savings, says Heberger. After a decade-long drought devastated parts of Australia, governments, farmers, businesses, and citizens got even more serious about saving water. The result is that South Australians use four to five times less water per capita than Californians. 

Potential solutions include investing in more water efficient infrastructure and technology, reclaiming more waste and stormwater, and reducing water used for landscaping and irrigation.

Although some have called for more dams to store more water when it's available, there aren't many good places left in the state to put them, says Heberger, who notes that California already has nearly 1,000. At the same time, environmentalists express concerns about impacts on fish and other wildlife.                                                                                                                                              

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