The amount of water in California’s mountain snowpack is only about half of average for early winter, a state Department of Water Resources official said Wednesday, urging conservation but noting that a dry start doesn’t always predict the season’s outcome.
An automated sensor network on 260 snow courses statewide found the snow-water content to be 52% of average to date, said Sean de Guzman, chief of the department’s snow surveys and water supply forecasting section.
De Guzman found a bit of better news after snowshoeing out into a clearing at Phillips Station in the Sierra Nevada, where manual measurements have been conducted since 1941.
The measurement there found 30.5 inches (77.4 centimeters) of snow with a water content of 10.5 inches (26.6 centimeters), which equates to 93% of average to date and 42% of the April 1 average, the key date when the snowpack is typically at its peak.
The Sierra snowpack typically supplies about 30% of the water needed by California when spring comes and it begins to melt, eventually ending up in aqueducts and reservoirs.
Yet California continues to experience evidence of climate change and climate variation, de Guzman said.
Fall 2020 has been extremely dry, especially in the Sierra, and comes on the heels of last year’s below-average snow and precipitation so “it remains critical that all Californians make water conservation a way of life,” he said.
He noted, however, that two-thirds of the wettest months — January and February — are yet to come and just a handful of storms can create the bulk of the Sierra snowpack.
The past summer saw wildfires burn huge swaths of California including Sierra forests, which will affect the snowpack, de Guzman said.
The scorched areas could alter snow retention due to loss of tree canopy and increased snowmelt along with reduced percolation of water into the ground due to severely burned soils, he said.