California snowpack deepest in four decades

California’s snowpack levels are at their highest point in four decades, after a series of severe storms deluged the region last month, according to state water officials.

The total snow water equivalent accumulated has risen to 33.7 inches, or 205 percent of the average for this time of year, the California Department of Water Resources announced on Wednesday.

These results, tabulated from 130 electronic snow sensors statewide, are outpacing the 1982-1983 season which previously set the record.

The agency warned, however, that “two months still remain” until state snowpack usually peaks and that “every day it does not rain or snow, the conditions are drying.”

“California has always experienced some degree of swings between wet and dry, but the past few months have demonstrated how much more extreme those swings are becoming,” Karla Nemeth, director of the California Department of Water Resources, said in a statement.

Nine storm systems known as “atmospheric rivers” began battering California and other Western areas with heavy rains and snow over a three-week period starting in late December, according to a recent update from the National Integrated Drought Information System.

During these storms, 80 percent of full seasonal snowpack was deposited in California, the report found. Statewide, the precipitation accumulated over those three weeks amounted to 11.2 inches, or 46 percent of a full year.

The Department of Water Resources acknowledged on Wednesday that these atmospheric rivers provided “a significant boost” to California snowpack, following the driest three-year period on record.

But if the Golden State returns to dry weather over the next two months — similar to the conditions last season — the significant early snowpack could disappear, the Department of Water Resources cautioned.

Periodic bouts of precipitation over the next few months will therefore be critical to achieving the biggest water supply benefits from the snow and rain that has already fallen, the agency noted.

On average, snowpack from the Sierra Nevada mountains — knowns as California’s “frozen reservoir” — fulfills about 30 percent of the state’s water needs and helps determine how water administrators manage supplies, water officials explained. 

“Large snow totals like today are a welcome sight but also present new challenges for water managers as they walk the fine line between water supply and flood control,” Sean de Guzman, the Department of Water Resources’s unit manager for snow surveys and water supply forecasting, said in a statement.

“As we move into the snowmelt season in the spring, water managers will work to manage flood risk and optimize the snowpack’s water supply benefits during peak demands in the summer,” de Guzman added.

Despite the welcome wet weather thus far, the agency stressed that Californians should continue to use water wisely and actively conserve it.

“California is preparing for more intense and dangerous climate swings by bolstering both drought and flood preparation,” Nemeth said.

“While today’s results are good news for water supplies, we know from experience how quickly snowpack can disappear if dry conditions return in the months ahead,” she added.