The Bureau of Reclamation’s Central Valley Project began Water Year (WY) 2012 (October 1, 2011 - September 30, 2012) with approximately 9.3 million acre-feet of water (78 percent of capacity) in six key CVP reservoirs.
The total reservoir storage is the combined amount of water remaining at the end of WY 2011 in Shasta, Trinity, Folsom, New Melones and Millerton Reservoirs and the Federal share of the joint federal/state San Luis Reservoir. The 15-year average carry-over for these reservoirs is 6.9 million acre-feet of storage (58 percent of capacity). An acre-foot is the volume of water sufficient to cover an acre of land to a depth of 1 foot, enough water to sustain a typical California household of four for 1 year.
Two tables follow, one showing reservoir capacities and end-of-year storage comparisons for WY 2011 and 2010 for key CVP reservoirs and one comparing end-of-year storage for 2011, 2010, 2009, 2008, 2007 and 1977 (the driest year).
Precipitation in WY 2011 was about 145 percent of the historic seasonal average or 73 inches as measured at eight key locations in Northern California from the Upper Sacramento River watershed near Shasta, Calif., to the American River watershed near Blue Canyon, Calif. (Calif. Department of Water Resources’ Northern Sierra Nevada 8-Station Index). For the Friant Division, the precipitation total for the Huntington Lake station was 67 inches or 151 percent of the historic seasonal average.
During WY 2011, CVP powerplants generated about 5.5 billion kilowatt-hours. Project use consumed about 22 percent of this energy. The remaining energy was made available for marketing. The Mid-Pacific Region’s hydro-electric generators have a combined capacity of approximately 2.1 million kilowatts.
As WY 2012 gets under way, Reclamation will continue to monitor and evaluate hydrologic conditions as they develop. The initial forecast of CVP water supply allocations for the contract year (which begins March 1, 2012) will be made in late February 2012. The allocation will be adjusted monthly or more often if warranted, to reflect the updated snowpack and runoff. The current allocations and other background information are available at http://www.usbr.gov/mp/pa/water.
For additional information on the end-of-year storage for specific reservoirs or for general information about Reclamation programs, please visit http://www.usbr.gov/mp/cvo or contact the Public Affairs Office at 916-978-5100, TTY 916-978-5608, or e-mail [email protected].