SWP Increases Projected Water Supply Allocation by ACWA Staff Apr 23, 2024 Water News SACRAMENTO – The Department of Water Resources (DWR) today announced a further increase in the State Water Project (SWP) water supply allocation forecast for 2024. The forecasted allocation has increased to 40%, up from 30% last month. The State Water Project provides critical water supplies to 27 million Californians and farmers served by 29 public water agencies. Today’s increase would provide an additional 420,000 acre-feet of water, enough water to serve an estimated 1.5 million households for a year, according to a DWR news release. Today’s 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. April 1 is typically when California sees peak snowpack and the start of the snowmelt season. 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. “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,” stated State Water Contractors General Manager Jennifer Pierre in a news release. “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 is working with the U.S. Army Corp of Engineers to manage flood releases and maximize the capture and storage of water from the winter storms and spring runoff in its reservoirs. Since Jan. 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% of average and 94% of capacity and is expected to reach capacity next month. During the spring, the ability to move water supply south through the system will continue to be 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. This reduced pumping is expected to continue into late spring. The State Water Project anticipates increasing its pumping significantly this summer as soon as the fishery conditions and our State and federal operating permits allow. “This year highlights the challenges of moving water in wet periods with the current pumping infrastructure in the south Delta. We had both record low pumping for a wet year and high fish salvage at the pumps,” stated DWR Director Karla Nemeth in the department news release. “We need to be moving water when it’s wet so that we can ease conditions for people and fish when dry conditions return. It’s one more reason the Delta Conveyance Project, which would move water when the flows are high in a manner safer for fish, is a necessary climate adaptation project for California.” Had the Delta Conveyance Project been in place this winter, the State Water Project would have been able to capture an additional 909,000 acre-feet of water since Jan. 1. That’s enough water for 9.5 million people, or 3.1 million households, for a year. The updated State Water Project allocation forecast announced today anticipates delivery of 40% of requested supplies to contractors south of the Delta, which accounts for the majority of contractors; 65% of requested supplies to contractors north of the Delta; and 100% allocation to Feather River Settlement Contractors. Allocations are updated monthly as snowpack, rainfall, and runoff information is assessed, with a final allocation typically determined in May or June.