From the Department of Water Resources:
The first manual snow survey of the Sierra snowpack this winter found more snow than last year at this time, but the snow water equivalent as measured statewide remains far below average for this date.
The Department of Water Resources (DWR) conducted the survey today about 90 miles east of Sacramento on a plot along Highway 50 near Echo Summit. Snow covered the ground there to a depth of 21.3 inches, according to DWR’s Frank Gehrke, chief of the California Cooperative Snow Surveys Program who conducted the survey.
The snow water equivalent was 4 inches at that particular snow course, or 33 percent of average. Statewide, 105 electronic sensors in the Sierra detected a snow water equivalent of 4.8 inches, 50 percent of the multi-year average for December 30. That compares favorably with last Winter’s first survey, when the snow water equivalent statewide was only 20 percent of normal, which tied with 2012 as the driest readings on record.
DWR Director Mark Cowin said of today’s survey results: “Although this year’s survey shows a deeper snowpack than last year, California needs much more rain and snow than we’ve experienced over the past two years to end the drought in 2015. The department encourages Californians to continue their water conservation practices.”
Cowin said the state’s surface and groundwater reservoirs have been severely depleted during the drought, which now is in its fourth consecutive year. He said a snowpack built up significantly during the winter months would be needed to recharge the reservoirs to their historical averages as the snow melts during the late spring and summer months.
Generally, California’s snowpack supplies about a third of the water needed by the state’s residents, agriculture and industry as it melts in the late spring and summer.
Today’s electronic readings indicate that water content in the northern mountains is 57 percent of normal for the date and percent of the average on April 1, when the snowpack normally is at its peak before the spring melt. Electronic readings in the central Sierra show 45 percent of normal for the date and 16 percent of the April 1 average. The numbers for the southern Sierra are 48 percent of average for the date and 15 percent of the April 1 average.
DWR and cooperating agencies conduct manual snow surveys around the first of the month from January to May. The manual measurements supplement and check the accuracy of real-time electronic readings.
Results of today’s manual readings by DWR off Highway 50 near Echo summit are as follows:
Historic Comparison
The average January 1 snowpack water content at Phillips Station is about 12 inches; the April 1 average 27.6 inches. Phillips had its lowest early-January water content reading of 0.1 inch in 2012, in a snow depth of only 0.6 inches. On January 3, 2014, Phillips had 2.3 inches of water content in 9.3 inches of snow. Besides that reading and the similar one in 2012, the driest January readings at Phillips were in 1987 (0.9 inches of snowpack water content), 1981 (2 inches), 1976 (2.7 inches) and 2000 (3 inches). Records at Phillips go back 50 years.
DWR currently estimates it will be able to deliver only 10 percent of the slightly more than 4 million acre-feet of State Water Project (SWP) water requested for calendar year 2015 by the 29 public agencies that collectively supply more than 25 million Californians and nearly a million acres of irrigated farmland. It is hoped the initial 10 percent delivery estimate will increase as winter storms develop.
The final SWP allocation for calendar year 2014 was 5 percent of the slightly more than 4 million acre-feet requested. In 2013, it was 35 percent, and in 2012, the final allocation was 65 percent. It was 80 percent in 2011, up dramatically from an initial allocation of 25 percent. The final allocation was 50 percent in 2010, 40 percent in 2009, 35 percent in 2008, and 60 percent in 2007. The last 100-percent allocation – difficult to achieve even in wet years because of Delta pumping restrictions to protect threatened and endangered fish – was in 2006.
DWR weather watchers note that it’s early in the season with plenty of time for the snowpack to build. The concern, however, is that irrigation-dependent San Joaquin Valley farms and some other areas will be hard hit if Water Year 2015 ends as the fourth full year of drought. Storage in key reservoirs has increased due to heavy December rainfall but is still far below normal levels for the date.
Lake Oroville in Butte County, the State Water Project’s (SWP) principal reservoir, today is at only 38 percent of its 3.5 million acre-foot capacity (61 percent of its historical average for the date). Shasta Lake north of Redding, California’s and the federal Central Valley Project’s (CVP) largest reservoir, is at 41 percent of its 4.5 million acre-feet capacity (66 percent of average for the date). San Luis Reservoir, a critical south-of-Delta reservoir for both the State Water Project and Central Valley Project, is a mere 39 percent of its 2 million acre-foot capacity (58 percent of average for the date) due both to dry weather and Delta pumping restrictions to protect salmon and Delta smelt. Delta water is pumped into the offstream reservoir in winter and early spring for summer use in the Bay Area, San Joaquin Valley, Central Coast and Southern California.
Continuing dry weather prompted Director Cowin on December 13, 2013 to mobilize DWR’s drought management team “to offset potentially devastating impacts to citizen health, well-being and our economy.”
Governor Edmund G. Brown Jr. declared a drought emergency on January 17, 2014. In October, DWR announced the award of more than $200 million in grants to reduce drought impacts on local communities and improve access to water supplies.
Electronic snowpack readings are available on the Internet at: http://cdec.water.ca.gov/cdecapp/snowapp/sweq.action
Electronic reservoir readings may be found at: http://cdec.water.ca.gov/cdecapp/resapp/getResGraphsMain.action
Electronic precipitation readings are at: http://cdec.water.ca.gov/snow_rain.html
- For a broader snapshot of current and historical weather conditions, see:
Water Conditions Page: http://www.water.ca.gov/waterconditions/waterconditions.cfm
Drought Page: http://www.water.ca.gov/waterconditions/index.cfm
