Gillibrand, Colleagues Strongly Oppose Proposed EPA Rule That Would Threaten State, Tribal Rights To Regulate Water Quality

Gillibrand, Colleagues Strongly Oppose Proposed EPA Rule That Would Threaten State, Tribal Rights To Regulate Water Quality

Apr 9, 2026

Today, U.S. Senator Kirsten Gillibrand (D-NY) joined ten of her Senate Democratic colleagues in strongly opposing a proposed rule from the Environmental Protection Agency (EPA) that would threaten states and Tribes' ability to protect the quality of their water. The EPA's proposed rule would limit the application of Section 401 of the Clean Water Act, rendering states and Tribes effectively unable to regulate many of the water quality impacts of hydropower dams and other projects within their lands.

In their letter to EPA Administrator Lee Zeldin and Assistant Administrator for Water Jess Kramer, the senators warned that the proposed rule would eviscerate the Clean Water Act's core principle of cooperative federalism and leave states and Tribes without the necessary authority to protect their waters.

"For far too long, our Tribal communities have been subject to unjust legislation that undermines their autonomy and diminishes their quality of life," said Senator Gillibrand. "Under the Clean Water Act, the EPA successfully allowed states and Tribal communities to weigh in on projects that could affect the quality of water on their lands. This new proposed rule would limit their ability to address pollution and keep their water usable for current residents and future generations. I am urging EPA to abandon this rule and instead continue working with state and Tribal authorities as Congress intended."

The senators warned that EPA's proposed rule would also reduce opportunities for Tribes to protect water quality by repealing a provision from the 2023 rule that allows them to develop their own regulations.

"This is a step backward, and Tribes have not even had sufficient time to apply for or implement these new authorities before EPA seeks to reverse course. Rather than providing clarity, this change would create additional uncertainty in the regulatory process," wrote the senators.

"We urge EPA to preserve States and Tribes' broad authority under the Section 401 certification process," continued the senators. "The Clean Water Act has been successful for decades in large part because EPA has recognized and deferred to State and Tribal authority over water quality impacts within their lands. We respectfully request that EPA preserve this tradition of cooperative federalism."

Hydropower dams, more than 400 of which must be relicensed within the next decade, can lead to severe water quality impacts and habitat loss in stream systems. Dam operations can significantly alter water temperature, sediment, oxygen, and flow level, which could result in harmful algal blooms, making the water unusable for drinking or swimming. Because these impacts stem from the structure and operation of the dam itself rather than the discharge of additional pollutants, the senators cautioned that they could fall outside the scope of state and Tribal review under EPA's proposed rule.

"The Proposed Rule casts doubt on the state's ability to use the most effective tools to address pollution problems from hydropower projects," added the senators.

In addition to Senator Gillibrand, the letter was also signed by Senators Alex Padilla (D-CA), Richard Blumenthal (D-CT), Jeff Merkley (D-OR), Bernie Sanders (I-VT), Adam Schiff (D-CA), Jeanne Shaheen (D-NH), Chris Van Hollen (D-MD), Ron Wyden (D-OR), Patty Murray (D-WA), and Maria Cantwell (D-WA).

The letter is also supported by American Whitewater, Friends of the River, Conservation Law Foundation, Hydropower Reform Coalition, American Sustainable Business Network, Friends of Merrymeeting Bay, NETWORK Lobby, and South Yuba River Citizens League.

"Section 401 of the Clean Water Act is a proven, common-sense tool that ensures local voices are heard on local impacts. Tribal and state leaders must have a meaningful role in managing their water resources. Weakening this authority undermines critical safeguards that protect drinking water and public health," said Kelly Catlett, Senior Advisor, American Rivers Action Fund.

"EPA's proposal to weaken states' and Tribes' ability to protect their waters from harm caused by federally permitted projects is unjustified and unjustifiable," said Jon Devine, Director of Freshwater Ecosystems, NRDC.

"The most recent moves by Trump's EPA to weaken section 401 of the Clean Water Act erodes the right of states and Tribal Nations to enforce water quality standards, including conditionally approving or denying permits. Rather than giving corporations a free pass to pollute our water supply and put our public health at risk, protections for communities should be strengthened at this moment," said Mar Zepeda Salazar, Legislative Director, Climate Justice Alliance.

"EPA should not undercut the system of cooperative federalism set up by Congress that has allowed states and tribes to protect their local waterways from damaging federal projects for decades," said Nancy Stoner, Senior Attorney at the Environmental Law & Policy Center.

Full text of the letter is available here and below:  

Dear Administrator Zeldin and Assistant Administrator Kramer,

We write to express our strong objection to the Environmental Protection Agency's (EPA's) proposed rule limiting the application of Section 401 of the Clean Water Act, which would severely limit States and Tribes' ability to regulate the water quality impacts of hydropower dams within their lands. By denying States' and Tribes' right to protect their waters and water quality, the proposed rule would eviscerate the Clean Water Act's core principle of cooperative federalism.

Congress enacted Section 401 to address a specific regulatory gap: federally licensed or permitted activities that could affect water quality but would otherwise proceed without compliance with State and Tribal water quality requirements, which include designated uses (e.g., known drinking water sources), the criteria that protect those uses, and other requirements that relate to water quality. Section 401 ensures that States and Tribes retain authority to protect their waters and the communities dependent upon them before federal licenses are issued, reflecting Congress's express policy to "recognize, preserve, and protect the primary responsibilities and rights of States" in preventing pollution. 33 U.S.C. § 1251(b).

Contrary to this Congressional intent, EPA's proposed rule would severely constrict the scope of Section 401 water quality certifications, including their ability to address the impacts of more than 400 hydropower dams that must be relicensed within the next decade. Hydropower projects cause profound water quality impacts on stream systems, including: habitat loss; barriers to fish passage; harmful algae blooms; reductions in stream flows; alterations to stream geomorphology; and changes in temperature, dissolved oxygen, nutrients, metals bioaccumulation, and sediment-related conditions, like water clarity, silt, and erosion. These impacts often do not fall neatly into "discharges", and their integrated nature dictates that they are best addressed by looking at the "activity as a whole."

Take, for example, temperature. Hydropower alters the temperature regime of rivers, often to the detriment of cold-water species such as salmonids and other aquatic plants and animals that are adapted to colder waters. Water stored in reservoirs greatly increases the surface area exposed to heating by the sun and reservoir operations may reduce the extent of the area protected by shade. Large reservoirs "stratify" in summer: the water is warmer at the surface and cooler below the thermocline in deeper waters. Absent any control devices, or multi-level outlets, downstream temperature management is primarily achieved directly through flow management. In addition to changes in temperature due to reservoir storage and release, reservoirs also modify the temperature regime of downstream reaches by diminishing the volume of water below diversions for hydropower generation. Hydroelectric dams, which are generally built to take advantage of mountain gradients, also can block upstream fish migration; trapping fish in the typically warmer, valley reaches of a river, absent effective fish passage. Thus, in addition to the thermal impacts of the hydropower dams themselves, the facilities can prevent fish from reaching waters of appropriate temperature upstream.

As a result, diversions, reservoir storage, and dams contribute to altered water temperatures and flow regimes that injure and even kill salmon and other native aquatic species, encourage warm-water and non-native fishes, and alter the base of the food web. In addition, these conditions allow undesirable and toxic algae (e.g., Microcystis), and submerged nuisance aquatic vegetation (e.g., Egeria) to become established and potentially widespread. In sum, temperature impacts are directly related to hydroelectric facility construction and operations. Thus, as appropriate, certifications include requirements for temperature management to ensure protection of water quality and beneficial uses of a state's waters. At times, these conditions are best expressed as temperature and flow requirements at point source discharges - at other times, water quality certifications address the issues more effectively through conditions aimed at other actions, such as habitat restoration to provide increased riparian shade or refugia and replace upstream lost habitat, reservoir operation requirements to manage cold-water pools, posting to warn the public about dangerous toxins, or measures to monitor and control nuisance species. The Proposed Rule casts doubt on the state's ability to use the most effective tools to address pollution problems from hydropower projects.

In addition to severely limiting States and Tribes' ability to address the water quality impacts of hydropower dams, the rule is problematic for other Federally permitted activities as well, including pipelines and Section 404 permits for discharges of dredged or fill material.

Under the proposed rule, Section 401 certifications could only address the impacts of dredged or fill material on those portions of affected wetlands or other waters that constitute waters of the United States. Some of the affected wetlands that lack a "continuous surface connection" or streams that are deemed to lack "relatively permanent" flow under the new proposed "Waters of the United States" rule could not be addressed by Section 401 certifications. This limitation of certification authority will create problems, even in states like California that have state law water quality permitting authority broad enough to address all of the affected wetlands or other waters. Where under current law the project would need to obtain only a Section 401 certification from the State, the proposed rule would force the applicant to file and the State to process two applications for two approvals­-one for water quality certification and one for the state law permit-adding unnecessary delay and expense for both the State and the applicant.

Furthermore, the EPA's proposed rule would reduce opportunities for Tribes to protect water quality. The 2023 rule appropriately recognized that a Tribe's ability to develop regulations under Section 303(c) is not tied to its authority to exercise Section 401 to protect its waters. EPA now proposes to repeal this provision, removing a critical tool that supports Tribal water quality protection. This is a step backward, and Tribes have not even had sufficient time to apply for or implement these new authorities before EPA seeks to reverse course. Rather than providing clarity, this change would create additional uncertainty in the regulatory process.

We urge EPA to preserve States and Tribes' broad authority under the Section 401 certification process. The Clean Water Act has been successful for decades in large part because EPA has recognized and deferred to State and Tribal authority over water quality impacts within their lands. We respectfully request that EPA preserve this tradition of cooperative federalism.

Thank you for your consideration.

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