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Great Lakes Areas of Concern

  • Great Lakes Restoration Initiative Action Plan IV

    The U.S. Environmental Protection Agency announces an updated action plan for federal agencies and their partners under the Great Lakes Restoration Initiative to restore and protect the Great Lakes over the next five years.

The U.S.-Canada Great Lakes Water Quality Agreement (Annex 1 of the 2012 Protocol) defines AOCs as "geographic areas designated by the Parties where significant impairment of beneficial uses has occurred as a result of human activities at the local level." An AOC is a location that has experienced environmental degradation. EPA and other federal and state agencies are working to restore the 25 remaining U.S. AOCs in the Great Lakes basin.

AOC Map

Map of the US great lakes areas of concern

AOC List, Map and Contacts

Projects and Progress

photo of an aoc with water and native plants
  • Restoring Great Lakes Areas of Concern
  • Beneficial Use Impairments
  • Remedial Action Plans
  • Legacy Act

Delisted AOCs

United States:
  • Rochester Embayment (Oct. 2024)
  • Ashtabula River (Aug. 2021)
  • Lower Menominee (Aug. 2020)
  • White Lake (Oct. 2014)
  • Deer Lake (Oct. 2014)
  • Presque Isle Bay (Feb. 2013)
  • Oswego River (July 2006)
Canada:
  • Collingwood Harbour
  • Severn Sound
  • Wheatley Harbour

Related Information

  • Environment and Climate Change Canada: Great Lakes AOCs
  • Great Lakes Commission AOC Resources 
  • International Joint Commission
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on March 14, 2025
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