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CWA Section 401 Certification

Overview of CWA Section 401 Certification

Under Section 401 of the Clean Water Act (CWA), a federal agency may not issue a permit or license to conduct any activity that may result in any discharge into waters of the United States unless a Section 401 water quality certification is issued, or certification is waived. States and authorized tribes where the discharge would originate are generally responsible for issuing water quality certifications. In cases where a state or tribe does not have authority, EPA is responsible for issuing certification. 33 USC 1341. Some of the major federal licenses and permits subject to Section 401 include:

  • Clean Water Act Section 402 and 404 permits issued by EPA or the Corps,
  • Federal Energy Regulatory Commission (FERC) licenses for hydropower facilities and natural gas pipelines, and
  • Rivers and Harbors Act Section 9 and 10 permits.

The CWA provides that certifying authorities (states, authorized tribes, and EPA) must act on a Section 401 certification request "within a reasonable period of time (which shall not to exceed one year) after receipt" of such a request. A certifying authority may waive certification expressly, or by failing or refusing to act within the established reasonable period of time. In making decisions to grant, grant with conditions, or deny certification requests, certifying authorities consider whether the federally-licensed or permitted activity will comply with applicable water quality standards, effluent limitations, new source performance standards, toxic pollutants restrictions and other appropriate water quality requirements of state or tribal law.

A federal agency may not issue a license or permit for an activity that may result in a discharge into a water of the United States without a water quality certification or waiver.

Regulatory Requirements for CWA Section 401 Certification

Section 401 of the Clean Water Act (CWA) provides states and authorized tribes with an important tool to help protect the water quality of federally regulated waters within their borders, in collaboration with federal agencies. EPA's regulations at 40 CFR 121 (PDF) address Section 401 certification generally. EPA also has water quality certification regulations for federally-issued CWA Section 402 permits that are subject to the Section 401 certification requirements (40 CFR 124.53-124.55 (PDF)). Other federal agencies may also have Section 401 certification regulations for their licensing and permitting programs.

In accordance with Executive Order 13990, the U.S. Environmental Protection Agency (EPA) has announced its intention to reconsider and revise the 2020 Clean Water Act Section 401 Certification Rule (“401 Certification Rule”) found at 40 CFR Part 121. Information on upcoming outreach and engagement opportunities can be found here.

Additional Materials

2019 Guidance and 1971 Rule: EPA's 2019 Guidance and 1971 certification regulations are no longer in effect. Please refer to EPA Archive for EPA’s 2019 Guidance on CWA Section 401.