Scant snow in Sierra Nevada portends uncertain outlook for water flows
ECHO SUMMIT, Calif. – Water watchers anxious about California’s dry stretch got more bad news Tuesday – the critical snowpack in the Sierra Nevada is woefully light, raising fears that summer water flows will be down sharply.
The snowpack, measured every month during the wet season through April 1, generally provides about 14 million acre-feet of water annually, or four out of every 10 gallons of California’s drinking and farm water.
It is a crucial index of the state’s water health because the water from the melting snow flows to lakes and reservoirs during the spring and summer when there is little rain.
”Certainly, the snowpack is looking grim. It is probably between 20 percent and 25 percent of average for this time of year, based on the sensors, and we’re already 40 percent through the snow-accumulation period,” said Maurice Roos, top hydrologist with the state Department of Water Resources.
State officials measured 10.7 inches of snow off U.S. Highway 50 at Echo Summit on Tuesday, about 24 percent of normal, Water Resources spokesman Jeff Cohen said. The site, about 85 miles east of Sacramento, has an elevation of 6,800 feet.
Other monitoring points in the Sierra Nevada found 5.5 inches of snow at Alpha at the 7,600-foot level, about 13 percent of normal; 10.8 inches of snow at Darrington at 7,100 feet elevation, about 24 percent of normal; and 16.7 inches of snow at the Lyons Creek station at the 6,700-foot level, or about 35 percent of normal.
Overall, the Sierra snowpack is 22 percent of normal following the seventh driest December since record keeping began nearly 80 years ago.
A dramatic example of the light snowpack: The Tioga Pass through Yosemite National Park, normally closed by snow from November through June, reopened Dec. 22 after being closed for the winter at Thanksgiving.
Despite the discouraging figures, government water officials say reservoirs are brimming and there should be adequate supplies to make it through summer.
”Even though these are very low percentages, it’s early in the season,” Cohen said. ”January is the biggest snow month, followed by February, then March. Many times we’ve had drier than normal Decembers and ended up with above-normal years.”
But the buyers of federal water are not so optimistic. They note that most have been told already to expect cuts in water deliveries, with reductions of up to 50 percent for some agricultural users and 25 percent for the urban Santa Clara water system. They have experienced reductions even during wet years.
”If we don’t see a turnaround rain- or snow-wise, we could see those already significant shortages expanded,” said Jason Peltier, who represents the federal water contractors that purchase water from the Central Valley Project.
”There is even a distinct possibility that Santa Clara will have to go offline and stop taking water from the Central Valley Project, and that was with a normal or dry scenario,” Peltier said.
His group includes mostly agricultural water districts serving about 20,000 growers on a third of the state’s irrigated farm land, but also has urban users in Contra Costa, Santa Clara and Roseville, among other areas.
The State Water Project, which serves a mix of about 30 percent farms and 70 percent cities, has delivered full supplies during all of the 1990s except for 1994, a drought year.