The California Department of Water Resources (DWR) announced on Tuesday that it would increase its State Water Project (SWP) allocation forecast for the coming year after multiple moisture-laden storms hit California in March.
Why It Matters
California reservoirs depend on precipitation in the winter months, especially snow that falls in the Sierra Nevada mountains and then melts and runs into the reservoirs when temperatures warm in the spring. Snowpack occurring throughout the winter season provides about 30 percent of the state’s water needs.
Moisture-laden storms typically begin to taper off in March, but several storms have brought beneficial precipitation to the state this month. State water officials are crediting these storms for the recent SWP allocation forecast increase.
What to Know
On Tuesday, the DWR announced that the allocation has increased to 40 percent of requested water supplies, a 5 percent jump from last month. In December, DWR officials increased allocation to 15 percent of requested supplies.
The SWP is a water storage and delivery system extending more than 700 miles, two-thirds the length of California. According to a map from the DWR, the SWP is made up of five field divisions. The divisions are Oroville, Delta, San Luis, San Joaquin, and Southern. The SWP provides water to 29 public water agencies that serve 27 million Californians.
California Department of Water Resources
Because of the extra precipitation, the SWP’s water storage at Lake Oroville in northern California increased this month. The lake is now 86 percent full, which is 121 percent of its average for this time of year. The SWP water storage at San Luis Reservoir is nearly full as well.
As of the most recent snowpack surveys, statewide snowpack is 96 percent of normal for this time of year. It is 119 percent of normal in northern California, 89 percent of normal in central California and 87 percent of normal in southern California.
A spokesperson for the DWR told Newsweek that during the severe widespread drought in 2022, the DWR only allocated 5 percent of requested water supplies. The state’s water situation recovered in 2023, allowing for 100 percent allocation. In 2024, state water officials allocated 40 percent.
What People Are Saying
DWR Director Karla Nemeth said in a press release: “As we near the end of the wet season, our focus shifts to snowpack runoff and whether temperatures allow for a slow melt so we can capture as much of that runoff as possible. Despite periods of extremely dry conditions this season, water managers have been able to effectively capture, move, and store water for use later this year while also maintaining flood protection.”
What Happens Next
The final SWP allocation is determined in May or June. Next week, the final snowpack survey of the season will occur on April 1, which is when the Sierra Nevada snowpack typically peaks.