State increases projected water supply allocation again

The Department of Water Resources (DWR) announced a further increase in the State Water Project (SWP) water supply allocation to 40 percent, up from 30 percent announced last month. This is the third increase since the initial allocation announced in December 2023.

DWR says the allocation update is based on an 800,000 acre-foot increase in storage at Lake Oroville and the latest snow survey data from the all-important April 1 measurements.  Statewide, the snowpack remains near average at 99 percent of average for this date. The spring forecast in the latest snow runoff report, known as Bulletin 120, also anticipates above average runoff this spring.

Since January 1, storage has increased by 917,000 acre-feet at Lake Oroville and by 178,125 acre-feet at San Luis Reservoir. Oroville is currently at 124 percent of average and 94 percent of capacity and is expected to reach capacity next month.

The state’s ability to send water south has been impacted by the presence of threatened and endangered fish species near the State Water Project pumping facility in the south Delta. The presence of these fish species has triggered state and federal regulations that significantly reduce the pumping from the Delta into the California Aqueduct. This reduction in pumping has limited the ability to move and store water into San Luis Reservoir.

“While we are glad to see this modest allocation increase for public water agencies who rely on SWP supplies, it is still far below the amount of water we need,” said Jennifer Pierre, General Manager of the State Water Contractors. “Water deliveries should be far higher in a good water year like we’ve had — there is a lot of water in the system, California reservoirs are full, and runoff from snowpack melt is still to come. Today’s modest allocation highlights just how difficult it is to operate within current regulatory constraints and with infrastructure in need of modernization. Even in a good water year, moving water effectively and efficiently under the current regime is difficult.”

The State Water Project anticipates increasing its pumping significantly this summer as soon as the fishery conditions and State and federal operating permits allow.