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Clean Water Act — Section 401 Water Quality Certifications

The federal Clean Water Act enables us to approve, condition, or deny projects proposed in waters of the United States — including wetlands — when a federal permit is needed.

Issuance of a Section 401 Certification means that we have reasonable assurance that the applicant's project will comply with state water quality standards and other requirements for aquatic resources protection under our authority. Section 401 Certification can cover both the construction and operation of a proposed project.  Conditions of the 401 Certification become conditions of the federal permit or license.  

Certifications for hydropower licenses

We work with the Federal Energy Regulatory Commission (FERC) licensing process for hydropower dams. When an applicant requests a license, either to re-license an existing dam or for new construction, we work with the utility and review studies, analyses, and plans. If we determine that water quality standards are attainable, a 401 certification is issued with conditions to ensure that the standards will be met. These conditions become part of the new FERC license.

Non-hydropower Section 401 Certifications

Washington's Section 401 Certifications provide a strong opportunity to protect and enhance water quality, aquatic species and habitats, water resources, coastal resources, floodplains, and other environmental elements.

Certifications for NPDES federal permits

National Pollutant Discharge Elimination System (NPDES) permits limit the quality and quantity of wastewater discharge into surface waters like rivers, lakes, and streams. We write NPDES permits for all non-federal discharges in the state, except those on tribal lands.