State water managers boost deliveries for 2024

California water managers have announced an increase to this year’s allocations from the State Water Project due to the healthy Sierra Nevada snowpack and Lake Oroville’s bountiful supply.

State Water Project is one of California’s two largest storage and delivery systems and supplies water to 27 million people and 750,000 acres of farmland, including the Zone 7 Water Agency in the Tri-Valley.

The system’s forecasted water allocation was increased from 30% of requested supplies to 40% since March, officials with the state Department of Water Resources said last week.

The increase is enough to deliver an additional 420,000 acre-feet of water — enough to supply roughly 1.5 million households for a year.

The decision to boost allocations is supported by an 800,000 acre-foot increase in storage at Lake Oroville, one of the state’s main reservoirs, according to state officials.

Currently, Oroville is holding about 3.3 million acre-feet of water, which is 95% of its total storage capacity and 125% of average for this time of year, according to data on the department’s website.

Additional factors include the fact that the state’s 17 major reservoirs are cumulatively at about 118% of average, the key snow survey data from April 1 clocked in at more than 100% of normal and the spring runoff forecast numbers are also above average.

DWR director Karla Nemeth used the announcement as an opportunity to plug Gov. Gavin Newsom’s controversial plan to build the Delta Conveyance Project, a proposed tunnel and pump system to move water around the Sacramento-San Joaquin River Delta to water agencies and farms to the south.

“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,” Nemeth said. “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.”

The increased allocations announced April 23 include 40% of requested supplies to water systems and farms south of the Delta, which accounts for most contractors.

It also includes 65% of requested supplies to contractors north of the Delta and 100% allocation to systems in the Feather River watershed.

In addition to the state’s announcement, the U.S. Bureau of Reclamation announced another increase in its water supply deliveries from the federally managed Central Valley Project.

For 2024, all north-of-Delta Central Valley Project users are currently at 100% of requested supplies and south-of-Delta agricultural contractors’ supplies have been increased from 35% to 40%.

The Central Valley Project delivers water to wholesalers and retailers in 29 of the state’s 58 counties, including 5 million acre-feet to farms and 600,000 acre-feet — a year’s supply for roughly 2.5 million people — to cities and towns.

“Hydrologic conditions have improved enough that we are able to provide this gradual increase,” said Karl Stock, the bureau’s California-Great Basin regional director. “We realize that our contractors were hoping to see a greater amount of water, and we understand how critical irrigation is to California agriculture and the surrounding communities. However, continued uncertainty in long-term hydrology and regulatory constraints necessitate Reclamation’s approach with available water supplies.”