SACRAMENTO — Manual and electronic readings today indicate that California’s mountain snowpack is holding above average water content despite a dry January. Statewide, real-time sensors show that snowpack water content is 78 percent of the April 1 seasonal average. This compares to an average reading of 55 percent for today’s date. The above-average readings are due to heavy storms in October, November and December. January so far has recorded only about 13 percent of average precipitation for the month. “We are still optimistic for a good water supply, but realize that we can come up short any given year,” said DWR Director Mark Cowin. “Our unpredictable weather and delivery restrictions make it clear that conservation must always be one of our top priorities.”………..
DWR estimates it will be able to deliver 60 percent of requested State Water Project (SWP) water this year. The estimate will be adjusted as hydrologic and regulatory conditions continue to develop.
In 2010, the SWP delivered 50 percent of a requested 4,172,126 acre-feet, up from a record-low initial projection of 5 percent due to lingering effects of the 2007-2009 drought. Deliveries were 60 percent of requests in 2007, 35 percent in 2008, and 40 percent in 2009.
The last 100 percent allocation – difficult to achieve even in wet years due to
pumping restrictions to protect threatened and endangered fish – was in 2006.
The SWP delivers water to more than 25 million Californians and nearly a million acres of irrigated farmland.
The mountain snowpack provides approximately one-third of the water for
California’s households, industry and farms as it slowly melts into streams and
Manual surveys are conducted up and down the state’s mountain ranges on or
about the first of January, February, March, April and May. The manual surveys supplement and provide accuracy checks to real-time electronic readings as the snowpack builds, then melts in early spring and summer. April 1 is when snowpack water content normally is at its peak before the spring runoff Results of today’s manual readings by DWR off Highway 50 near Echo Summit are as follow:
60.6 inches 28 inches 133
56 inches 24 inches 125
63.8 inches 28.4 inches 145
60 inches 24.4 inches 126
Electronic readings indicate that water content in the northern mountains is 108 percent of normal for the date and 65 percent of the April 1 seasonal average.
Readings for the central Sierra are 126 percent of normal for the date 75 percent of the April 1 average. The numbers for the southern Sierra are176 and 97.
On December 28, the date of this winter’s first manual survey, percentages of the snowpack’s normal April 1 water content were 57 percent for the northern Sierra, 61 percent for the central Sierra, and 78 percent in the south.
On this date last year, snowpack water content readings were 80 percent of the April 1 average in the north, 60 percent in the central ranges, 67 percent in the south, and 68 percent statewide California’s reservoirs are fed both by rain and snowpack runoff.
Most of the state’s major reservoirs are above normal storage levels for the date.
Lake Oroville in Butte County, the State Water Project’s principal reservoir, is 102 percent of average for the date (68 percent of capacity). Remaining winter weather will determine whether it fills to its 3.5 million acre-foot capacity. Lake Shasta north of Redding, the federal Central Valley Project’s largest reservoir with a capacity of 4.5 million acre-feet, is at 112 percent of average (76 percent of capacity).
Statewide snowpack readings are available on the Internet at
Historic readings from snowpack sensors are posted at
Electronic reservoir level readings may be found at
The Department of Water Resources operates and maintains the State Water Project, provides dam safety and flood control and inspection services, assists local water districts in water management and water conservation planning, and plans for future statewide water needs.
Contact the DWR Public Affairs Office for more information about DWR’s water activities