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  2. 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 requirements, which include water quality standards, effluent limitations, new source performance standards, toxic pollutants restrictions and other appropriate water quality requirements of state or tribal law.

Once the federal licensing or permitting agency receives both the application for the license or permit and a certification, it must immediately notify EPA under the neighboring jurisdiction process set forth in CWA section 401(a)(2). A federal agency may not issue a license or permit for an activity that may result in a discharge into waters of the United States prior to the completion of the CWA section 401(a)(2) process.

  • Read Clean Water Act Section 401

Regulatory Requirements for CWA Section 401 Certification

On September 14, 2023, the U.S. Environmental Protection Agency (EPA or the Agency) announced the final 2023 Clean Water Act Section 401 Water Quality Certification Improvement Rule (2023 Rule). The final rule is grounded in the fundamental authority granted by Congress to states, territories, and Tribes to protect water resources that are essential to healthy people and thriving communities over the past 50 years. On September 27, 2023, the final 2023 Clean Water Act Section 401 Water Quality Certification Improvement Rule was published in the Federal Register. The final 2023 Rule went into effect on November 27, 2023. More information on the final 2023 Rule is available here. 

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 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). Other federal agencies may also have CWA section 401 certification regulations for their licensing and permitting programs.

  • 2023 CWA Section 401 Water Quality Certification Improvement Rule
  • 2020 CWA Section 401 Certification Rule
  • 1971 EPA regulations for Section 401 (PDF)

CWA Section 401 Certification

  • Section 401 Certification Home
    • Basic Information on Section 401 Certification
    • Read Section 401
  • Final 2023 Clean Water Act Section 401 Water Quality Certification Improvement Rule
    • Treatment in a Similar Manner as a State (TAS) for Clean Water Act Section 401
    • Treatment in a Similar Manner as a State (TAS) for Clean Water Act Section 401(a)(2)
  • Outreach and Engagement on CWA Section 401 Certification
  • Resources when EPA acts as the Certifying Authority
  • Contact Us
Contact Us about CWA Section 401 Certification
Contact Us about CWA Section 401 Certification to ask a question, provide feedback, or report a problem.
Last updated on August 30, 2024
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