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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 state or authorized tribe where the discharge would originate issues a Section 401 water quality certification verifying compliance with existing water quality requirements or waives the certification requirement. Some of the major federal licenses and permits subject to Section 401 include:

  • Section 402 and 404 permits (in non-delegated states),
  • Federal Energy Regulatory Commission (FERC) hydropower licenses, and
  • Rivers and Harbors Act Section 9 and 10 permits.
The CWA provides that states and authorized tribes must act on their Section 401 authority within "any reasonable time not to exceed one year", with the reasonable period being decided by the federal permitting or licensing agency. A state or authorized tribe may waive the certification voluntarily, or by failing or refusing to act within the established reasonable time period. States and authorized tribes make their decisions to grant, grant with conditions, or deny certification requests primarily by ensuring 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 without a certification or waiver from the state or authorized tribe where the discharge originates.

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