401 Water Quality Certifications for hydropower licenses

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EPA's 2020 Section 401 rule vacated Oct. 21, 2021

The U.S. District Court for the Northern District of California vacated and remanded the "EPA 2020 Clean Water Act Section 401 Certification Rule," which went into effect Sept. 11, 2020. We will continue to review and issue Section 401 water quality certification decisions while federal agencies are reviewing the court decision and considering next steps. Please review our main Section 401 Water Quality Certification page for the most up-to-date information.

When an applicant requests a license, either to re-license an existing dam or for new construction, we work with the utility to review studies, analyses, and plans.

If we determine that water quality standards are attainable, a 401 Water Quality Certification is issued, with conditions to ensure that the standards will be met. These conditions become part of the Federal Energy Regulatory Commission (FERC) license.

401 Guidance Manual

The Water Quality Certifications for Existing Hydropower Dams Guidance Manual spells out our expectations of applicants who want us to certify that a hydropower project meets Washington's water quality standards. This manual is useful for utility districts, local governments, tribes, and the public.

New water quality 401 applications

Existing 401 certifications for dams

We have a 401 Water Quality Certification decision for the following projects. If you would like to access a copy of these decisions, please access our list of existing 401 certifications for dams.