California lawmakers are proposing legislation that aims to reestablish safeguards for the state’s streams and wetlands in response to a Supreme Court ruling limiting federal clean water regulations.

Supporters say the legislation has taken on heightened urgency as the Trump administration begins to scale back protections for many streams and wetlands, making them vulnerable to pollution and worsening water quality.

“We need clean water to drink, to grow our food, to safely bathe and swim in, to support healthy ecosystems and the environment,” said state Sen. Ben Allen (D-Santa Monica), who introduced the bill. “It’s about protecting our water supply, and it’s a common-sense measure that simply restores the protections that our waterways have always enjoyed since 1948.”

Federal standards have since 1948 limited pollution discharges into waterways. Such standards later became a central part of the federal Clean Water Act, adopted in 1972.

In Sackett vs. EPA, the Supreme Court ruled in 2023 that Clean Water Act protections don’t apply to many wetlands and ephemeral streams, which flow when it rains but otherwise sit dry much of the time. The court ruled that the law’s protections for the “waters of the United States” apply only to wetlands and streams that are directly connected to navigable waterways.

The decision was supported by groups representing developers and the agriculture industry, who say the EPA had overstepped its authority by restricting private property owners from developing their land.

California officials and clean water advocates counter that the rollback of protections will jeopardize vital water sources and ecosystems throughout the arid West.

“It should be recognized as not just a threat to water quality but overall quality of life, and frankly, a threat to our state,” said Assemblymember Ash Kalra (D-San José), the bill’s co-author. Kalra said the court ruling has stripped federal protections “from many of our most precious wetlands and streams, each a crucial linkage in a complex water network that undergirds every animal, every plant, every human being in our state.”

The bill, SB 601, would restore previous protections for California’s wetlands and streams by requiring permits for pollution discharges from businesses and construction projects. The measure calls for state standards that meet or exceed the regulations previously in place during the Biden administration.

“This was a system that was working well,” Allen said. “We’ve got to step up.”

The legislation, he said, effectively rolls back the clock prior to the court decision to maintain protections, and “enshrines a new framework into state law.” Under the bill, titled the Right to Clean Water Act, the State Water Resources Control Board would be tasked with implementing and enforcing the rules.

A cormorant presides over what’s left of a snorkeling pool in the drying Kern River in Bakersfield.

(Gary Kazanjian / For The Times)

“It’s critical that our state protects our waterways in the same way that we have over the last 50 years,” said Sean Bothwell, executive of the group California Coastkeeper Alliance, which is supporting the legislation.

He called the Supreme Court ruling misguided, saying it was biased toward waterways in the wetter East Coast climate, and doesn’t fit California’s reality, where many streams flow only when it rains.

“Our Mediterranean climate doesn’t allow for our rivers and streams, and the creeks that flow into them, to flow permanently,” Bothwell said. “What this bill does is it maintains the protections that Californians have enjoyed.”

While the legislation is being discussed in Sacramento, the federal Environmental Protection Agency has begun to revise the so-called Waters of the United States rule to bring regulations into line with the Supreme Court ruling.

Announcing plans for the regulatory rollback last week, the EPA said the agency, acting together with the Army Corps of Engineers, will “move quickly to ensure that a revised definition follows the law, reduces red-tape, cuts overall permitting costs, and lowers the cost of doing business.” The EPA said it will begin its review by seeking input from stakeholders.

“We want clean water for all Americans supported by clear and consistent rules,” EPA Administrator Lee Zeldin said in the announcement. He said the previous version of the regulations “placed unfair burdens on the American people and drove up the cost of doing business.”

The EPA has also announced plans to roll back more than two dozen other regulations, which environmentalists say would severely harm the nation’s progress in addressing air and water pollution.

Bothwell said the EPA’s new rule, once adopted, might go beyond the Supreme Court ruling and make it “more sweeping than it already was.”

Without the state legislation, he said, the combination of the court decision and the Trump administration’s pullback of regulations will leave seasonal streams and many wetlands without Clean Water Act protections.

“We can no longer rely upon the federal government to protect and provide clean and affordable water,” Bothwell said.

State officials and environmental advocates have said because about 90% of California’s wetlands have already been drained and destroyed, strong protections for those that remain are vital.

Whether protective measures are in place could affect the state’s aquatic ecosystems. There are nearly 4,000 freshwater species in California, and researchers at the Public Policy Institute of California said in a report last year that there are no protections in place for many species that are threatened.

“Our waters are connected. Our freshwater ecosystems, groundwater aquifers, rivers, wetlands and other waterways are all interconnected,” said Ashley Overhouse, a water policy advisor for the nonprofit group Defenders of Wildlife.

She said when pollution flows into wetlands or streams, the effects on threatened species and water quality can be widespread, harming ecosystems that are also suffering from the effects of climate change.

The bill would provide “clarity and efficient protections for the state at a time of regulatory and political uncertainty,” Overhouse said.

The ultimate goal, she said, is to ensure “a future where clean, healthy water is guaranteed for all communities and all wildlife.”