CWA Section 401 Water Quality Certification: EPA Rethinking It (Again)

On July 7, 2025, the U.S. Environmental Protection Agency (EPA) published a notice inviting public comments on its 2023 Water Quality Certification Improvement Rule. That rule governs Clean Water Act (CWA) Section 401 Water Quality Certifications (WQCs), including those for hydropower projects in Maine.

Obtaining a § 401 WQC is a crucial step in the federal licensing process, particularly for hydropower projects regulated by the Federal Energy Regulatory Commission (FERC). While FERC oversees energy licensing, the CWA designates states (as well as tribal nations) with the obligation to issue water quality certifications. Under § 401, a Federal license cannot be issued unless the designated entity either certifies that the project meets state water quality standards, explicitly waives certification, or fails to act within the timeframe allowed. This process was designed to ensure that state water quality concerns are timely addressed alongside Federal energy considerations. 

While the 2023 (Biden-era) Rule aimed to clarify and streamline the certification process, the Trump EPA appears to be pursuing even more significant reform. Hence, EPA is now seeking public feedback through listening sessions and written comments from certifying authorities, project applicants, and other stakeholders. Listening sessions are scheduled for:

July 16, 2025, 1:00–4:30 p.m. ET; and

July 30, 2025, 1:00–4:30 p.m. ET

Register here to attend.

The EPA is especially interested in input on:

·       Certification timelines

·       Clarity on what constitutes a complete application

·       State and Federal agency coordination

·       Interpretations of key provisions in the 2023 Rule, including:

o   The scope of certification (i.e., which project impacts should be considered);

o   Meaning of “other appropriate requirements of State law;” and

o   Level of consideration of impacts on downstream jurisdictions.

The EPA notice indicates that the responses to these topic areas will assist the Agency in improving permitting efficiency, protecting water quality, reducing procedural confusion, and ensuring that certifications reflect meaningful and lawful water quality reviews rather than bureaucratic obstacles.

The Maine Department of Environmental Protection (DEP), which manages Maine’s § 401 certification process, anticipates receiving 17 new hydropower certification applications over the next five years as part of the FERC relicensing cycle. Hence, this comment period provides a valuable opportunity for potentially impacted entities to influence the regulatory process and help ensure a smoother § 401 certification and recertification experience.

Comments on the rule can be submitted to the EPA via Regulations.gov (Docket ID No. EPA-HQ-OW-2025-0272) and further information on the listening sessions is available at Outreach and Engagement | US EPA.