California's Department of Water Resources (DWR) has announced an update to the State Water Project (SWP) allocation forecast for 2025. The allocation has increased to 20 percent of requested supplies, up from 15 percent in December. The SWP provides water to 29 public water agencies that serve 27 million Californians.
While January has been incredibly dry across California, storm runoff into the state’s reservoirs came in higher than forecasted at the end of December allowing for a modest allocation increase. Storms in late November and early December had a positive impact by saturating the ground, allowing for storms through December to more efficiently runoff into reservoirs.
More storms are needed, and the long-range forecast does hint at a return to wet conditions in early February that could bring much-needed rain and snow.
“We are in the middle of our biggest months for precipitation for California, and unfortunately January has been very dry, putting a significant dent in our season,” said DWR Director Karla Nemeth. “A return to wet weather is critical for our season’s success and it will take many more storms to make up the deficit and further boost water supply deliveries.”
Despite the dry conditions, California has effectively managed its reservoirs to keep storage above average for this time of year. Lake Oroville, the State Water Project’s largest reservoir, is currently at 127 percent of average for this time of year. San Luis Reservoir, which is jointly operated by the U.S. Bureau of Reclamation, is at 102 percent of average for this time of year. Reservoirs in Southern California are also near or above their historical averages.
Each year, DWR provides SWP allocation forecasts based on available water storage, projected water supply, and water demands. Allocations are updated monthly as snowpack, rainfall, and runoff information is assessed, with a final allocation typically determined in May or June. As the winter progresses, if California sees an increase in rain and snowfall, the allocation forecast may increase. Learn more about how the State Water Project allocation process works at https://water.ca.gov/News/Blog/2025/Jan-25/Get-the-Facts-About-the-State....
The allocation forecast notice to State Water Contractors and historical data on SWP allocations are available at https://water.ca.gov/programs/state-water-project/management/swp-water-c....
