The U.S. Environmental Protection Agency (EPA) has unveiled a proposal to amend Section 401 of the Clean Water Act, a critical provision that governs water quality certifications for federal projects and significantly impacts the authority of states and federally recognized tribes to oversee these developments. Experts contend that the proposed changes risk dismantling one of the few potent legal avenues available to tribes for asserting treaty rights and safeguarding their water resources, potentially undermining their ability to protect their citizens and ancestral lands. Miles Johnson, Legal Director at Columbia Riverkeeper, an organization dedicated to protecting the Columbia River ecosystem, explained that the modifications target a vital mechanism for both states and tribes, affecting their capacity to impose conditions or, in extreme scenarios, halt federal projects or those under federal jurisdiction.

Developers seeking to undertake projects such as dams, mines, large-scale data centers, or extensive pipeline networks are legally obligated to navigate a comprehensive permitting process. A cornerstone of this process involves obtaining certification from the relevant state or tribal government, confirming that the proposed project will adhere to federal water quality standards. Under regulations established by the Biden administration in 2023, this review, often referred to as an "activity as a whole" assessment, allowed tribes and states to conduct holistic evaluations. These reviews considered a broad spectrum of potential impacts on water quality, encompassing not only direct pollution discharges but also the risks associated with accidental spills, the potential damage to culturally significant resources, and the broader ecological consequences for local wildlife.

However, the EPA’s newly proposed rule seeks to drastically narrow the scope of these reviews, limiting them to "discharge only." This means that both states and tribes would be permitted to scrutinize projects solely based on the quantity of pollutants they are projected to release, thereby significantly curtailing their oversight capabilities.

Furthermore, the proposed rule introduces substantial alterations to how tribes can acquire regulatory authority under the "Treatment in a Similar Manner as a State" (TAS) program. The TAS program is a crucial mechanism that empowers tribes to act as environmental regulators, granting them the ability to directly establish conditions aimed at preventing pollution in waters adjacent to their lands. To date, a limited number of tribal nations, precisely 84, have successfully obtained TAS status, enabling them to participate in the review of federal projects impacting their territories. Currently, Section 401 of the Clean Water Act provides a pathway for tribes, regardless of their size or resource capacity, to obtain the authority to review water quality standards and exert regulatory powers, provided they can demonstrate the necessary capacity and resources. The proposed revisions would significantly restrict these powers, mandating that only tribes with TAS status can conduct evaluations, and even then, only through a separate, more stringent authorization process.

Heather Tanana, a law professor at the University of Denver, emphasized the profound importance of treaty rights as a robust legal framework for holding federal and state governments, as well as third-party actors, accountable. She noted that pursuing legal action to uphold these rights is often a protracted, expensive, and complex undertaking, underscoring the necessity of alternative enforcement mechanisms. Tanana explained that a reversion to the regulatory landscape preceding 2023 would place an increased burden on tribes, requiring them to demonstrate a more substantial organizational capacity, often necessitating the establishment of dedicated environmental or water departments. She highlighted the significant disparities in available resources among tribal nations, with variations in their access to revenue streams, staffing levels, and the existence and scale of their environmental departments, ranging from a single individual to a larger team.

During the Obama administration, tribes actively advocated for the establishment of a baseline rule that would grant all tribes some level of input in federal project reviews, even as they pursued TAS status. However, industry opposition during the public comment period and the subsequent political shift in 2024 led to the withdrawal of this proposed rule by the EPA in December. Patrick Hunter, a senior attorney at the Southern Environmental Law Center, pointed out that out of the approximately 7,500 projects submitted during the Biden administration, fewer than one percent were ultimately denied. The vast majority of these projects were approved, often with stipulated conditions designed to mitigate potential water pollution, such as the implementation of best management practices during construction or the installation of sediment control measures. Tanana corroborated these findings, indicating that tribal review outcomes mirrored this trend of project approval with mitigation requirements.

The EPA’s own 2025 report on tribal consultations, which documented extensive engagement with Indigenous communities, revealed overwhelming opposition from tribes to the proposed changes. Tanana relayed the consistent message from tribal representatives: "Don’t change it," urging the agency to refrain from implementing measures that would impede their sovereign ability to protect their waters and communities. A 30-day public comment period on the proposed rule is currently underway, and it is widely anticipated that the finalized rule will face significant legal challenges. Gussie Lord, head of tribal partnerships at Earthjustice, articulated the deep-seated responsibility tribes hold to safeguard the rivers and waterways that have sustained their communities for millennia, predating the formation of the United States itself, and affirmed that they are exploring every available recourse to preserve their traditional ways of life.