The EPA wants to eliminate one of the few ways that tribes can protect their water

Earlier this month, the Environmental Protection Agency announced a proposal to revise the Clean Water Act, specifically a section of the law that regulates water quality and limits states’ and tribes’ authority over federal projects, as well as how tribes can gain the authority to conduct those reviews. Experts say the move would dissolve one of the few tools tribes have to enforce treaty rights and hamper their ability to protect tribal citizens. 

“What the Trump administration is proposing to modify here is a really important tool for states and tribes, because it gets at their ability to put conditions on or, in extreme cases, block projects that are either proposed by the federal government or under the jurisdiction of the federal government,” said Miles Johnson, legal director at Columbia Riverkeeper, an organization that works on issues affecting the Columbia River. 

Developers seeking to build dams, mines, data centers, or pipelines must navigate a permitting process to do so. One requirement in the process is obtaining certification from a tribe or state confirming that the project meets federal water quality standards. Currently, tribes and states conduct holistic reviews of projects, known as “activity as a whole”, evaluating all potential impacts on water quality, including spill risks, threats to cultural resources, and impacts on wildlife. This approach was established under the Biden administration in 2023.

However, the newly proposed rule would limit reviews to “discharge only,” where both states and tribes are able to review projects solely based on how much pollution they would release, narrowing the scope of oversight.

The proposed rule also changes how tribes can gain regulatory authority to assess water quality under the Treatment in a Similar Manner as a State program, or TAS. Under that program, tribes are able to act as regulators, one of the few tools available to them, and directly set conditions to limit factors that would pollute waters near tribal lands. To date, only 84 tribal nations have received TAS status, allowing them to review federal projects. Currently, Section 401 of the Clean Water Act allows tribes that can demonstrate the capacity and resources the ability to review water quality standards, expanding regulatory powers beyond tribes with larger resources. The proposed change would shrink those powers, allowing only TAS tribes to perform evaluations through a separate, more rigorous authorization program.

“Treaty rights are one of the strongest mechanisms to enforce against the federal government, against the state, against third-party actors, and in litigation,” said Heather Tanana, a law professor at the University of Colorado. “It takes years, it takes money, it’s complicated to do, and so you want these other mechanisms.”

A reversion to pre-2023 rules, Tanana said, would put higher demands on tribes to show larger-scale capacity, often in the form of dedicated water departments.

“There’s such a wide variance in tribes of what resources are available to them. Do they have other sources of revenue, right? How many staff do they have? Do they have their own environmental departments? Is it one person, or is it 10?” said Tanana. 

During the Biden administration, tribes advocated for a baseline rule allowing all tribes some input in federal projects while seeking TAS status, but industry pushback during the comment period and a Trump win during the general election in 2024 led to its withdrawal from the EPA in December.

Patrick Hunter, a senior attorney at the Southern Environmental Law Center, noted that of 7,500 projects submitted during the Biden administration, fewer than 1 percent were denied. Most were approved with conditions such as mitigation measures and sediment traps to prevent water pollution during construction. Tanana said tribal review outcomes were similar.

The EPA’s 2025 report on tribal consultations highlighted widespread opposition to changes. “The clear feedback from the tribes was, ‘Don’t change it,'” said Tanana. “‘You’re going to make it harder for us to exercise our sovereignty to protect our waters and protect our community.’”

A 30-day public comment period on the proposed rule is currently underway. The rule is expected to face litigation after finalization. 

“Tribes have an obligation to care for the rivers and waterways that have sustained their communities since before the existence of the United States and are weighing every option to protect their way of life,” said Gussie Lord, head of tribal partnerships at Earthjustice.