The Milwaukee Estuary was designated an Area of Concern under the Great Lakes Water Quality Agreement of 1987 because of historical modifications and pollutant loads that contributed toxic contaminants to the AOC and Lake Michigan. Sediments contaminated with PCBs, PAHs and heavy metals contribute to nearly all of the eleven beneficial use impairments within the original boundaries of the AOC. The rivers within the AOC were also historically modified (straightened and dredged) to accommodate large vessel commercial shipping. While Milwaukee still maintains a viable commercial port, some of the river reaches within the estuary are no longer maintained through dredging.

The original boundaries of the AOC included the lower 5 km of the Milwaukee River downstream of North Avenue Dam; the lower 4.8 km of the Menomonee River downstream of 35th Street; the lower 4 km of the Kinnickinnic River downstream of Chase Avenue; the inner and outer harbors; and the nearshore waters of Lake Michigan, bounded by a line extending north from Sheridan Park to the city of Milwaukee’s Linnwood water intake.

In 2008, the boundaries of the AOC were expanded for the purposes of addressing sites that contributed significant loads of contaminated sediments to the estuary. These expanded portions of the AOC are associated with the beneficial use impairments that are directly connected to contaminated sediment (see Beneficial Use Impairments tab).

The DNR worked with community stakeholders to develop a Remedial Action Plan (RAP) in 1991, with updates in 1994 and 1999. Since that time, much work has been completed and significant progress made towards improving conditions in the AOC. DNR is committed to making progress in the AOC sufficient to eventually delist, or eliminate, the Area of Concern designation, and to that end has begun working again with stakeholders identifying goals and actions necessary to address legacy contamination in the AOC.

The main priorities for the Milwaukee Estuary AOC include:

  • remediation of contaminated sediments in tributaries and nearshore waters of Lake Michigan
  • non-point source pollution control
  • improving water quality for recreation 
  • enhancing fish and wildlife habitat and populations

Eleven of the beneficial uses identified by the International Joint Commission are impaired or suspected to be impaired for the Milwaukee Estuary AOC. The full list is below, click on any individual impairment for further information, including listing and delisting guidelines as specified by the IJC: 

Click here for the Wisconsin DNR's BUI Summary, and here for the full Remedial Action Plan update. 


Community Advisory Committee

The Milwaukee Estuary Area of Concern CAC (CAC) is called to be the long‐term voice and leader for cleaning up and delisting the Milwaukee Estuary AOC. To this end the CAC provides a structured way for individual citizens to share their opinions and perspectives on cleanup efforts, and on how policies and programs affect citizens who live and work in the watersheds.

The purpose of the CAC is four-fold: 

  1. Review and provide comment on the annual Remedial Action Plan (RAP) and participate in the BUI removal process.
  2. Devise and assist in implementation of strategies for building public and community support to enact recommendations contained in the Remedial Action Plan for the Milwaukee Estuary Area of Concern;
  3. Provide a forum for meaningful and appropriate resident and local stakeholder input into remediation and restoration efforts, and;
  4. Advise state and federal agencies on Milwaukee Estuary AOC remediation and restoration.

Core Values/Guiding Principles of the CAC:

  • Fostering a sense of public responsibility for restoring and maintaining the ecological integrity of the Milwaukee Estuary;
  • Ensuring the expedient development and implementation of a Remedial Action Plan (RAP) for the Milwaukee Estuary Area of Concern (AOC) 
  • Cultivating a network of diverse audiences and facilitating outreach to increase citizen engagement and public awareness support of Milwaukee Estuary AOC remediation and restoration
  • Working together to identify and overcome obstacles to restoring the beneficial uses of the AOC and participate in the BUI removal process.
  • Ensuring that planning steps and actions taken to improve the health of the AOC are driven by participatory planning, sound science, and independent evaluation of planned restoration work.