A dry January and February could make water supply this year in the Central Sierra Nevada similar to last year, when below-average snowpack and new regulations led to some tightening.
The California Department of Water Resources will conduct its third official snow survey of the winter on Friday. Current estimates show that, while reservoirs levels look strong, snowpack is below average.
The DWR says snowpack in the Central Sierra is about 67 percent of the average to-date, and about 58 percent of the average for the entire rain season — which runs from July 1 to June 30.
Don Pedro reservoir is 98 percent of its historic level, and New Melones is 111 percent, according to the department.
About a third of the state’s water, and most of the local water supply, comes from Sierra Nevada snowpack melt.
Long-term weather forecasts from the National Oceanic and Atmospheric Administration predict dry conditions the rest of the winter.
“We may not see a March miracle,” Glen Nunnelley, an associate engineer with Tuolumne County’s largest water purveyor, the Tuolumne Utilities District, told the district Board of Directors on Tuesday.
“Right now, it’s very difficult to predict how it’s going to go.”
Should the dry weather hold, Nunnelley and TUD Engineer Tom Scesa said the district will likely ask PG&E to help the district maximize its water supply for the summer. TUD purchases most of its water from Pinecrest and Lyons reservoirs through a contract with PG&E.
A dry year and a new state regulation on the lake level at Pinecrest led to a tight summer water supply for TUD last year, and PG&E helped out by cutting down on the water diverted out of Pinecrest to power the Spring Gap project. Even with efforts by the utility company and TUD, district customers were still asked to conserve water through the summer of 2012.
“Essentially, they’re looking very similar,” Scesa said of 2012 and 2013.
On the other hand, Dion said he’s predicting adequate water supply for Calaveras County. CCWD receives its water from sources on the Stanislaus and Mokelumne rivers.
“We’ve had a fairly dry year … but carryover storage was pretty good and has remained pretty good,” he said.
Some Central Valley farmers might not have such good fortune, and according to the Bureau of Reclamation, the combination of dry winter conditions and restrictions on pumping is leading to an outlook of a low water supply.
The bureau said Monday that the wet December was followed by one of the driest combined Januaries and Februaries on record, and water supplies from the Sacramento-San Joaquin Delta have been reduced this year to protect the threatened delta smelt.
Reclamation officials said agricultural contractors on the west side of the San Joaquin Valley will receive an initial water allocation of 25 percent of requested deliveries from the Central Valley Project. Municipal, industrial and other water contractors will receive 75 percent.