Results of the snow survey by the California Department of Water Resources (DWR) show Sierra snowpack conditions at 118 percent of normal for this time of year.

While this would normally be a positive indication that the state’s water supply is in good shape, DWR also announced that it will need to further reduce Delta pumping starting today to comply with a federal court order limiting water exports to Southern California, the Bay Area and Central Valley.

State Water Project exports, which would typically be at about 8,000 cfs this time of year to fill south of Delta storage and provide water to communities and farms, will be cut to about one-quarter of that amount to protect Delta smelt that might be impacted by water project operations. This reduction initially will last up to seven days.

The latest snow survey was the third of the 2008 snowfall season. The most recent electronic sensor readings show Northern Sierra snow water equivalents at 122 percent of normal for this date, the Central Sierra at 110 percent, and the Southern Sierra at 130 percent. Statewide, the percentage of normal is at 118 percent. Electronic sensor readings one year ago showed the Northern Sierra at 69 percent of normal, the Central Sierra at 64 percent and the Southern Sierra at 52 percent. The statewide average was 63 percent.

The Delta pumping reductions are a result of Federal Judge Oliver Wanger’s decision last December to curtail pumping by state and federal water projects to protect the threatened Delta smelt, a tiny fish vital to the ecosystem that has seen its population decline drastically in past years.

This year’s pumping reduction will reduce the amount of water that can be allocated to the 29 state water contractors this year between 11 and 30 percent.

Northern California reservoirs generally show storage levels at 30 percent to 60 percent of capacity. It’s hoped that a substantial spring snowmelt will refill those facilities and help meet the demand for water this summer. Information on reservoir levels can be found at http://watersupplyconditions.water.ca.gov/current_conditions.pdf.

“California’s snow pack is in good shape with statewide average water content just over the normal April 1 peak,” said DWR Hydrology Branch Chief Arthur Hinojosa. “Nevertheless, additional precipitation is still needed to alleviate the deficits to water supply conditions that existed at the start of the season.”

The next manual survey is tentatively scheduled for April 1, 2008. DWR’s Public Affairs Office will issue a news advisory confirming the date.

Importance of Snow Surveying

Snow-water content is important in determining the coming year's water supply. The measurements help hydrologists prepare water supply forecasts as well as provide others, such as hydroelectric power companies and the recreation industry, with much needed data.

Monitoring is coordinated by the Department of Water Resources as part of the multi-agency California Cooperative Snow Surveys Program. Surveyors from more than 50 agencies and utilities visit hundreds of snow measurement courses in California’s mountains each month to gauge the amount of water in the snow pack.