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Great Lakes Areas of Concern

  • Accelerated Cleanup and Restoration of the Great Lakes

    EPA Announces $1 Billion Investment from the Bipartisan Infrastructure Law Will Significantly Accelerate Cleanup and Restoration of Great Lakes

  • Spirit Lake in St. Louis Area of Concern Cleanup Continues

    The large Spirit Lake  environmental cleanup includes dredging, capping and monitoring impacted sediment. The cleanup supports the eventual delisting of the St. Louis River AOC and will result in benefits to people and the ecological system.

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

Great Lakes AOC Map Updated Jan. 2023
  • AOC List, Map and Contacts
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:
  • 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 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 31, 2023
United States Environmental Protection Agency

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