California snowpack is light this year, but water supply still okay

San Francisco Chronicle/Marisa Lagos, 4/3/12. "Califonia snowpack at 55% of normal, survey shows."

"Is that all?"

"The water content of California's mountain snowpack is at a disappointing 55 percent of normal, according to the snow survey conducted Monday morning.  April's survey of the snowpack is considered the most important of the year, said Mark Cowin, director of the state's Department of Water Resources. The snowpack is normally at its peak in early April, just before it begins to melt and feed the state's streams, reservoirs and aquifers. "An unusually wet March improved conditions, but did not make up for the previous dry months," Cowin said in a statement. "The take-home message is that we've had a dry winter and although good reservoir storage will lessen impacts this summer, we need to be prepared for a potentially dry 2013." The crucial reading means the state will probably deliver just half of the 4 million acre-feet of water requested by members of the state water project this year, after an unusually wet 2011 helped fill up the state's reservoir storage. An acre-foot is 325,851 gallons of water - enough water to supply one to two households for a year.

 

Winter readings vital.  California's mountain snowpack normally provides about one-third of the state's water, making the wintertime readings crucial to water districts and other agencies that distribute water to households, farms and others. Monday's manual readings were conducted off Highway 50 near Echo Summit in the Sierra Nevada. While the overall statewide readings averaged out around 55 percent, electronic readings in the central Sierra showed the water content of the snowpack there at 51 percent of average, while the southern Sierra was at just 39 percent of average.Things were much worse before a series of winter storms pounded the Golden State last month: March's survey showed the water content in the snowpack at just 34 percent of average.Two of the state's most important reservoirs, Lake Oroville in Butte County and Lake Shasta in Shasta County, are at 84 percent and 86 percent full, respectively. 

 

Allocation in drought.  Last year, the state delivered 80 percent of the requested water, but officials said a 50 percent allocation is "not severely low." In 2008, for example - the middle of a two-year drought - just 35 percent was allocated.  The 29 public agencies that are part of the state water project serve more than 25 million Californians as well as almost a million acres of farmland. There will be one more survey this year, in May."

 

Reference -  Mercury News/Paul Rogers, 2/28/12, same location, Sierra snowpack at 30%,  big improvement in 1 month.

 

Posted by Kathy Meeh