California Gov. Gavin Newsom announced on Dec. 23 an agreement with the Biden administration to regulate water supplies that serve up to 30 million residents.

“We know what the future has in store for our state: hotter hots and drier dries. That means we have to do everything we can now to prepare and ensure our water infrastructure can handle these extremes,” Newsom said in a statement. “Thanks to the support of the Biden-Harris administration, California is taking action to make our water systems more resilient and lay the groundwork for new capacity in the future.”

Three years in the making, the agreement included collaboration from the California Department of Water Resources, the U.S. Fish and Wildlife Service, the National Marine Fisheries Service, and the California Department of Fish and Wildlife.

Changes are meant to increase resiliency to “extreme swings” between flooding and droughts, according to the governor’s office.

“The new framework supercharges our adaptive management and enables project operators to work with water users and the broader public to better manage the system to benefit millions of Californians and endangered fish species,” Karla Nemeth, California Department of Water Resources director, said in the same statement. “Extreme storms and extended droughts mean we need to be as nimble as possible in operating our water infrastructure.”

Endangered species will benefit from increased water flow, habitat restoration, and hatchery monitoring, according to the agreement.

A decision signed by the U.S. Bureau of Reclamation on Dec. 20 dictates how water is moved through the state’s Central Valley Project.

The project takes water from as far north as Redding and distributes it as far south as Bakersfield 400 miles away through a series of dams, reservoirs, canals, and aqueducts.

“The resilience of the Central Valley Project, with its importance to the agricultural industry and drinking water deliveries across California, is critical to the state’s water supply future,” Mike Brain, the bureau’s principal deputy assistant secretary for water and science, said in a statement. “The revised operating plan will improve regulatory certainty for water users and provide a more stable water supply for communities, farms, and fish.”

Reclamation Commissioner Camille Calimlim Touton said the plan will complement efforts to fund water storage capacity developments and drought plans.

Additionally, the reclamation bureau announced on Dec. 23 that public negotiations are set to consider long-term water contracts for certain wildlife refuge areas.

Public comment will be accepted on Jan. 7 and 9 in Sacramento.

The Newsom administration has been working on expanding California’s water supply infrastructure.

The state received approval in November for an operating permit for the State Water Project after lengthy environmental reviews.

Communities statewide received $880 million in grants to fund 395 projects over the past fiscal year to benefit about 12 million residents.

The state has also increased its capacity to capture rainwater and recharge underground reservoirs.

Approximately 740 billion gallons of rainwater wash out to sea every year in California, according to a February report from the nonprofit think tank Pacific Institute.

Nationwide, an average of about 53 billion gallons per day of fresh water are lost to the oceans, researchers estimated.

“The numbers are clear. It’s time to elevate the role of stormwater capture in the national water conversation,” Bruk Berhanu, senior researcher at the Pacific Institute and lead author of the report, said in a statement. “There is vast opportunity for stormwater capture strategies to help solve many of these challenges, enhancing overall water resilience.”

Included in the newly announced agreement are steps to integrate projects championed by the governor—the Delta Conveyance Project and the Sites Reservoir.

Mitigating earthquake damage is the prime focus of the ambitious delta project—which proposes building a water tunnel about 150 feet underground that runs for 45 miles in the Central Valley.

Costs are estimated at $20 billion, and the project has seen opposition from groups concerned about environmental and community impacts.

The proposed Sites Reservoir would divert water from the Sacramento River to flood about 13,200 acres in Glenn and Colusa counties—situated northwest of Sacramento. The system would consist of a bridge, two reservoirs, 11 dams to manage water levels, and a newly constructed conveyance system to distribute water to nearby communities.

Sites Reservoir would hold enough water to supply about 3 million homes for a year, helping preserve water during rainy seasons for use later in the year when most needed.

Projected to cost $4 billion, the project has faced numerous legal challenges from environmental groups and others.

A Yolo County court rejected in June a petition to block the plan, a decision the governor applauded.

“California needs more water storage, and we have no time to waste—projects like the Sites Reservoir will capture rain and snow runoff to supply millions of homes with clean drinking water,” Newsom said in a statement. “We’re approaching this work with urgency, everything from water storage to clean energy and transportation projects.”