In key Sierra measure, California registers thickest snowpack in years

Frank Gehrke, chief of the snow survey program for the state Department of Water Resources, leads a Sierra Nevada snowpack measurement in El Dorado County on March 30, 2017. Frank Gehrke, chief of the snow survey program for the state Department of Water Resources, leads a Sierra Nevada snowpack measurement in El Dorado County on March 30, 2017. Image 1 of / 137 Caption Close In key Sierra measure, California registers thickest snowpack in years 1 / 137 Back to Gallery

State surveyors waded into the icy Sierra Nevada on Thursday to take stock of the snow before it begins its crucial melt into rivers and reservoirs and found just what they expected: one of the biggest bounties in California history.

At Phillips Station south of Lake Tahoe in El Dorado County, where officials have taken measurements to forecast water supplies since 1941, snowpack was a whopping 183 percent of average for the date.

More importantly, snowpack across the entire Sierra range at this crucial point in the season — when snow levels are typically at their peak — measured 164 percent of average, according to state’s system of automated sensors. The tally has been higher just three times since 1970.

“It’s been very good from a snow accumulation standpoint,” said Frank Gehrke, chief of the snow survey program for the state Department of Water Resources, as he stood amid flurries at the measurement site.

Just two years ago, when surveyors trekked to 6,873-foot-elevation Phillips Station with their long, cylindrical gauges, there was no snow to put them in at all. Statewide snowpack came in at a dismal 5 percent of the norm.

This year’s frothy cache means a welcome boost for state and local water systems that have begun their recovery after five dry years, securing a virtual end to California’s historic drought.

While Gov. Jerry Brown has not rescinded a statewide emergency drought declaration, which ushered in a period of unprecedented water rationing, his office has said it would likely drop the order if the spring snow measurements ran high.

The snowpack, which state officials gauge not by height but water content, provides about a third of California’s water.

The state has received a near-constant barrage of storms this winter. Many areas have seen not only snow, which is piled up 50 feet at some spots in the southern Sierra, but heavy rains and wind that have brought flooding, mudslides and damage to roads and bridges.

Kurtis Alexander is a San Francisco Chronicle staff writer. Email: kalexander@sfchronicle.com Twitter: @kurtisalexander