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CWA Section 401 Certification

Basic Information on 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, verifying compliance with water quality requirements, 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. Some of the major federal licenses and permits subject to Section 401 include:

  • Clean Water Act Section 402 and 404 permits (in non-delegated states),
  • 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 voluntarily, 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.

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