Proposed Clean Water Act Section 401 Rulemaking: States and Tribes Would Lose More Ability to Protect Environment
Kevin Tahara
Another day, another brick removed from the wall of environmental protection by the Trump administration. In January of 2026, the Environmental Protection Agency (EPA) announced a proposed rule to update how the EPA handles section 401 of the Clean Water Act (CWA).[1] Section 401 gives states and tribes the authority to review and issue water quality certifications for projects within their jurisdiction that federal agencies have granted permits or licenses related to discharges into Waters of the United States (WOTUS).[2] Additionally, impacts to non-WOTUS water sources can be considered in certain circumstances.[3] Under the current section 401, states and tribes have broad discretion to review projects; they can evaluate whether the activity will comply with “applicable water quality requirements”[4] and consider project-wide impacts, such as disruption to water flow of a river.[5] If a state or tribe denies certification, then the activity is not approved to move forward.[6] Additionally, states and tribes can set prerequisites for their respective approval of these permits or licenses, such as effluent limits and monitoring.[7] Moreover, state created conditions can include ‘any other appropriate requirement of State law,’ which allows states to address other issues like climate change.[8]
The scope of the review and regulatory process will be dramatically different under the 2026 proposed rulemaking. The scope of review will now be limited to WOTUS exclusively, and impacts to non-WOTUS will no longer be valid concerns.[9] Given that the EPA is currently in the process of tightening of scope of WOTUS,[10] water sources that are not “relatively permanent,”[11] like streams, wetlands, and headwaters, will no longer be eligible to be considered under project impacts.[12] These waterbodies are known to provide a number of benefits, and reduced protection jeopardizes these valuable resources.[13] Additionally, the reviews for water quality can only pertain to ‘point source discharge.’[14] This is a drastic shift because projects may discharge water that meets regulatory standards, but now states lose the ability to base approval decisions on broader, project-wide environmental impacts such as downstream impacts from a dam or potential impacts to water quality issues due to construction and operation of an oil pipeline.[15] States would also lose the ability to consider a project’s potential climate change impact during the review process.[16]
Another proposed area of change is that states will have less control over the approval process due to the EPA’s proposal to streamline the process. States will no longer be able to ask for additional documents that differ from the set list of federally required documents,[17] which prevents states from performing a higher level of review if they think that the federally required documents are insufficient. Furthermore, states will be limited in making the water quality certifications based solely on discharge limitations already in the CWA “and any applicable and appropriate state water quality-related regulatory requirements for discharges.”[18] This action further reduces a state’s ability to consider other environmental factors besides strictly effluent discharge.
Tribes would specifically be affected by the proposed rule because they will no longer be granted “treatment as a state” (TAS) just for project approvals under section 401. Previously under section 401, EPA could grant tribes TAS without tribes creating new EPA approved water quality standards by allowing tribes to use pre-existing water quality standards like tribal water codes.[19] Instead, tribes will now need to first receive TAS under section 303(c).[20] This action will make it harder for tribes to receive EPA approval due to the higher time and resource burden. A tribe seeking approval under section 303(c) must have the staff and resources to set water quality standards and updating them over time; tribes who lack the resources needed to hire and retain the required full-time scientific and administrative staff will struggle to be granted 303(c) approval.[21] Because State water quality standards often do not apply to tribal land, if a tribe is not able create a section 303(c) compliant water quality standards program, there will now be a regulatory gap for projects that could impact tribal water quality.[22] Tribes therefore are at risk of being shut out of the environmental regulation discussion to the detriment of their water quality.
This proposed rule matters because the current version of section 401 has served as an effective means for states and tribes to prevent approval of potentially harmful developmental projects including oil and gas pipelines and coal export terminals.[23] The EPA claims that the changes would “return [Section 401] to its proper statutory purpose, protecting water quality while eliminating regulatory overreach that has imposed an unnecessary burden on critical infrastructure projects.”[24] Specifically, “states and tribes are no longer able to use Section 401 to shut down projects for reasons that fall outside of the [CWA’s] statutory requirements and appropriate and applicable water quality-related regulations.”[25] While project development may have been slowed down by section 401 reviews, the EPA has historically favored not making changes to its rulemaking on this section for many administrations. Prior to Trump’s first term in office, EPA rulemaking for section 401 had not been substantially changed since 1971.[26] However President Trump’s administration already attempted to reduce state and tribal power in a 2020 rulemaking,[27] but those changes were largely rolled back under President Biden in 2023.[28] The proposed section 401 revision is just one more example of the Trump administration trying to create industry friendly conditions at the expense of the environment.
[1] 91 Fed. Reg. 2008 (proposed Jan. 15, 2026), https://www.epa.gov/ system/files/documents/2026-01/cwa-401-proposed-rule-preamble.pdf.
[2] U.S. Small Business Administration, EPA Proposes to Revise Water Quality Certification Regulations (Jan. 20, 2026) https://advocacy.sba.gov/2026/01/20/epa-proposes-to-revise-water-quality-certification-regulations/.
[3] John L. Watson, EPA Wants to Change the Scope of the Clean Water Act’s Rule 401 Certification Process. The Review Process Landscape Changes Dramatically, SpencerFane (Jan. 16, 2026) https://www. spencerfane.com/insight/epa-wants-to-change-the-scope-of-the-clean-water-acts-rule-401-certification-process-the-review-process-landscape-changes-dramatically/.
[4] 91 Fed. Reg. 2010 (proposed Jan. 15, 2026).
[5] See Teresa Tomassoni, New EPA Proposal Would Strip States’ and Tribes’ Authority to Block Oil and Gas Pipelines, Other Infrastructure Projects, Inside Climate News (Jan 14, 2026) https://insideclimatenews. org/news/14012026/epa-proposal-streamlines-oil-gas-infrastructure-approval/#:~:text=Under%20the%20proposal%2C%20states%20and,waterways%20qualify%20for%20federal%20protection.
[6] Environmental & Energy Law Program, Section 401 Water Quality Certification, Havard Law School, https://eelp.law.harvard.edu /tracker/section-401-water-quality-certification/ (last updated Jan 15, 2026).
[7] 91 Fed. Reg. 2010 (proposed Jan. 15, 2026).
[8] See Brooks Smith, et al., EPA’s Proposed CWA 401 Rule Narrows Scope of State Reviews, Reins in Timelines, Troutman Pepper Locke (Jan 20, 2026) https://www.environmentallawandpolicy.com/2026/01/epas-proposed-cwa-401-rule-narrows-scope-of-state-reviews-reins-in-timelines/.
[9] Watson, supra note 3.
[10] Environmental Protection Agency, Waters of the United States (Jan. 21, 2026) https://www.epa.gov/wotus. See generally Sackett v. EPA, 598 U.S. 651 (2023) for case law motivating EPA’s revised rulemaking.
[11] Environmental Protection Agency, 2025 Proposed “Waters of the United States (WOTUS) Rule Fact Sheet, https://www.epa.gov/system/files/ documents/2025-11/public_factsheet_wotus_nprm.pdf (accessed Mar. 13, 2026).
[12] Tomassoni, supra note 5.
[13] See, e.g., Restore America’s Estuaries, Proposed Revision of Clean Water Act Protections Threatens Healthy Water for Our Communities (Nov. 24, 2025) https://estuaries.org/proposed-revision-of-clean-water-act-protections-threatens-healthy-water-for-our-communities/.
[14] Watson, supra note 3.
[15] Id.
[16] Id.
[17] Eric Christensen, et al, The Pendulum Swings Back: Proposed Clean Water Act Section 401 Rule Resurrects Key Elements of 2020 Rule, Beveridge & Diamond (Jan. 29, 2026), https://www.bdlaw.com/ publications/the-pendulum-swings-back-proposed-clean-water-act-section-401-rule-resurrects-key-elements-of-2020-rule/.
[18] Smith, supra note 8.
[19] Earthjustice, Tribal Comments Updating the Water Quality Certification Regulations, Docket Number EPA–HQ–OW–2025–2929, at 46 (Feb. 17, 2026), https://earthjustice.org/wp-content/uploads/2026/02/2026.02.17-ej-narf-and-tribes-comments.pdf.
[20] Tad J. Macfarlan, et al., New EPA Proposal Seeks to Adopt a More Restrictive Section 401 Framework, K&L Gates (Feb. 2, 2026) https://www.klgates.com/New-EPA-Proposal-Seeks-to-Adopt-a-More-Restrictive-Section-401-Framework-2-2-2026.
[21] Earthjustice, supra note 19, at 46-47.
[22] Id. at 47.
[23] Maxine Joselow & Lisa Friedman, E.P.A Moves to Limit States’ Ability to Block Pipelines, The New York Times (Jan 13, 2026) https://www.nytimes .com/2026/01/13/climate/trump-clean-water-act-states.html.
[24] EPA Press Office, EPA Proposes CWA Section 401 Rule to Streamline Permitting, Unleash Economic Growth, and Protect America’s Waterways, United States Environmental protection agency (Jan. 13, 2026) https:// www.epa.gov/newsreleases/epa-proposes-cwa-section-401-rule-streamline-permitting-unleash-economic-growth-and.
[25] Id.
[26] See 91 Fed. Reg. 2014 (proposed Jan. 15, 2026).
[27] Christensen, supra note 17.
[28] See id.