After a dry start to California’s winter rainy season, a series of big storms that began around Thanksgiving delivered enough snow for the Sierra Nevada to begin 2020 in relatively good shape.
As of Dec. 31, the statewide Sierra Nevada snowpack — a major source of California’s water supply — stood at 94% of its historical average.
That’s the highest total in four years, when it came in at 106% on Dec. 31, 2015.
Officials from the state Department of Water Resources planned Thursday to conduct their first Sierra Nevada snowpack survey of the season, with the media in tow, at Phillips Station along Highway 50 near Sierra-at-Tahoe ski resort.
How much snow falls every winter is critical to California’s water picture. The snow, which forms a vast “frozen reservoir” over California’s 400-mile long Sierra mountain range, provides nearly one-third of the state’s water supply for cities and farms as it slowly melts in the spring and summer months, sending billions of gallons of clean, fresh water flowing down dozens of rivers and streams into reservoirs.
It also is key to the state’s ski industry, which suffered significantly during the 2012-16 drought that also caused residential water cutbacks from the Bay Area to San Diego, farm losses across the Central Valley as wells and reservoir levels dropped and increased wildfire risk for five years.
That drought was broken by the drenching winter of 2016-17, but ever since then, water officials have nervously monitored weather patterns, hopeful that drought conditions don’t re-emerge any time soon.
To that end, California begins 2020 in a fairly strong water outlook.
Most of the state’s largest reservoirs are currently near, or above, historical averages for this time of year, following last year’s wet winter, where the Sierra Nevada snowpack hit 161% of its historic average on April 1.
Shasta Lake, the state’s largest reservoir, near Redding, is currently 73% full, or 117% of normal. Lake Oroville, in Butte County, is currently 59% full, or 96% of normal. And San Luis Reservoir, near Los Banos, is 63% full, or 96% of its historical average.
Every winter, at the beginning of each month, state water officials and other government scientists fan out to take snow measurements at more than 260 sites, with electronic sensors and manual readings. The oldest snow survey location dates back to 1906. One, at Phillips Station, in El Dorado County off Highway 50, south of Lake Tahoe is regularly done with TV cameras and journalists joining in.