Great Lakes Areas of Concern (AOCs)

In the 1980s, the U.S. and Canada identified 43 degraded shoreline areas along the Great Lakes, termed “Areas of Concern” (AOCs). These areas, involving federal agencies, states, tribes, and local partners, are prioritized for cleanup and restoration under the Great Lakes Water Quality Agreement, which defines 14 potential Beneficial Use Impairments (BUIs).

To delist an AOC, each beneficial use impairment must be removed. The Great Lakes Restoration Initiative (GLRI), launched in 2010, accelerates efforts to clean up AOCs and remove BUIs through significant federal funding and collaboration among various stakeholders. The Great Lakes Legacy Act also supports sediment cleanups using a cost-sharing strategy.

Key Actions for AOCs

Developing Removal Criteria: States establish realistic, measurable targets for each BUI with input from local stakeholders.

Management Action Lists: Each AOC will develop a list of projects necessary to remove each impaired BUI, primarily focusing on sediment remediation and habitat restoration.

Implementation: Actions are funded through the GLRI and other funding, with the aim of improving environmental conditions to meet BUI removal targets and delist an AOC.

Monitoring and Delisting

Monitoring efforts assess whether BUI restoration targets have been met through various activities, including field sampling and citizen science. Once a BUI restoration target has been achieved, a BUI removal document is prepared with the local community, advisory committee and state concurrence. With that support, the BUI can be officially recommended for removal by the EPA. Once all BUIs are removed an AOC can request delisting.

As of October 2024, seven U.S. AOCs and three Canadian AOCs have been delisted. For a detailed understanding of the BUI removal process and AOC delisting, please visit Beneficial Use Impairments for the Great Lakes AOCs.

Ohio’s AOC Program

Ohio’s AOC Program addresses the goals set forth in Annex 1 of the Great Lakes Water Quality Agreement in Ohio’s four designated Areas of Concern. The AOC Program is administered by Ohio Lake Erie Commission in partnership with Ohio EPA. Ohio has three Areas of Concern in portions of the Black, Cuyahoga and Maumee rivers and adjacent areas. The Ashtabula River AOC was delisted in 2021. The remaining Ohio AOCs are at varying stages of progress toward meeting the goals and restoration process.

The Ohio AOC Program works in partnership with a wide network of federal, state and local partners including local Advisory Committees within each AOC. For more information on Ohio’s AOCs, please visit Ohio Areas of Concern.