Why do I need a State Water Quality Certification, CWA Section 401?

This certification is for state issuance of a State Water Quality Certification (401 Certification) for an activity or project requiring a federal permit or license, that may result in a discharge to waters of the U.S. States are given the authority to issue this certification through Section 401 of the Clean Water Act (CWA). Under §401, a federal agency cannot issue a permit or license until/unless the state has certified, conditionally certified or waived the 401 Certification. Issuing this certification ensures that the project will not violate surface water quality standards, adversely impact impaired waters (waters that do not meet water quality standards) and that the project complies with applicable water quality improvement plans (total maximum daily loads). This certification becomes a part of the federal permit or license. The certification is valid for the same time period as the permit or license, often issued for five-year terms.

When do I need a CWA401 Water Quality Certification?

1. If the USACE permit is a Nationwide or Regional General Permit:

a. A 401 WQC application submission to ADEQ is required if the certified activities of the project discharge within the Ordinary High Water Mark of a Water of the US (WUS) that is:

  • An Outstanding Arizona Water
  • An Impaired Water
  • A Not Attaining Water
  • A Lake

b. A 401 WQC application submission to ADEQ is not required if the WUS doesn’t meet the conditions in #1. The certified activities of the project are conditionally certified under the USACE Nationwide Permit and the Regional General Permits.

2. If the USACE is an Individual permit to the USACE or any other Federal Agency:

a. A 401 WQC application submission to ADEQ is required.

CWA 401 Application Forms

Application Form for State Certification of Activities Requiring a U.S. Army Corps of Engineers General or Nationwide Permit | Download Application >
Application Form for State Certification of Activities Requiring a U.S. Army Corps of Engineers Standard Individual Permit | Download Application >
Application Form for State Certification of Activities Requiring a Federal License or Permit (not Corps) | Download Application >


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