What California's improved snowpack means for the drought

When Frank Gehrke trudged up to Phillips Station in the Sierra Nevada on Wednesday he found what was missing at this time last year: Snow.

The aual spring snowpack survey, conducted by Gehrke of the Califoia Cooperative Snow Surveys Program for the Califoia Department of Water Resources, revealed a snowpack depth of 58.4 inches, about 97 percent of the station’s historical average.

The manual measurement shows a vast improvement from last year, when Gehrke plunged his measuring pole into dirt, revealing zero snow depth and zero water content. Last year, the statewide snowpack was 5 percent of the historical average, the lowest amount ever recorded, launching Gov. Jerry Brown’s drought emergency plan that requires Califoians to reduce water consumption by 25 percent.

While the latest survey shows tremendous improvement, snow accumulations from the recent El Niño winter were disappointing and certainly not the 150 percent above normal most meteorologists had predicted. The water content from snow throughout the Sierra measured 87 percent of the March 30 historical average, the DWR reported Wednesday.

Gehrke, standing at the station close to historic Echo Summit near Lake Tahoe, was surrounded by blankets of snow and a bevy of reporters when he delivered a mixed message conceing the state’s water supply.

“It is better than where we were,” he said. “But even though reservoir levels have improved, it is not rosy.”

The March 30-April 1 snow measurement is the most important of the year, typically when snow accumulations are highest. The spring survey is the final indicator of how much water Califoia will reap from the melting snowpack.

As the sun melts the snow on the state’s Sierra Nevada mountain range, the runoff slowly refills reservoirs that feed the State Water Project, a major source of Southe Califoia water. In a typical year, Califoia gets one-third its water from snowpack melt. Last week, the DWR raised the allocation from the State Water Project from 5 percent in 2014 to 45 percent, a sign that more water will be flowing to Central and Southe Califoia.

One month ago, the snowpack at Phillips Station was 58.3 inches deep, just slightly less, indicating storms have slowed to a trickle. February was a bust and March started strong but petered out, he said. Gehrke’s not expecting any new storms next month and said the Sierra snowpack had already begun melting.

Electronic snowpack readings were 97 percent in the Northe Sierra; 88 percent in the Central Sierra and 72 percent in the Southe Sierra, for a statewide average of 87 percent of normal, vastly superior to last year but well below normal.

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“This will improve conditions for both reservoir storage and stream flows but there will be ongoing effects of below average snowpack,” Gehrke said, adding a caveat that drought conditions remain in many parts of the state, including Southe Califoia.

Precipitation in eight Northe Califoia stations is at 51.9 inches, about 125 percent of average to date, but far from the 1997-1998 El Niño rain year totals of 82.4 inches, the department reported.

“The message is still very strong: Conservation measures are still important,” he said, as some parts of the state enter a fifth year of drought. Reservoir levels are increasing but mainly in Northe Califoia. At Lake Oroville, levels are at 113 percent of historical average, or about 85 percent of capacity, said DWR officials. Lake Shasta is at 109 percent of historical average and 88 percent capacity.

“The water levels as compared to last year are much better,” said DWR’s Jan Frazier. But it is not enough to reverse four of the driest years in state history. “We’ve been ruing on a deficit for so long that we are still in drought. We have not broken the drought, although water levels are much better,” Frazier said.

Levels at Southe Califoia reservoirs are well below normal. At Castaic Lake, which stores water bought from Northe Califoia, levels are 45 percent of historical average and only 40 percent capacity. Lake Perris is 43 percent and 36 percent, respectively.

Gehrke said runoff into the state aqueducts may be slow-going, as parched-dry soil soaks in moisture first, before letting it roll down stream. “Because of the dry soil, we will not bet the same kind of runoff,” he said. Water managers throughout the state will be looking to store as much new water, to prepare for the possibility of more drought, he said.

A near-normal snowpack “stops that downward slide,” but won’t reverse the state’s drought, he said. Unless Mother Nature tus on the spigot in the upcoming fall and winter, water managers will emphasize conservation and practice storage for at least another year. “Now we are clearly looking at next year,” he said.