Milwaukee Estuary Area of Concern Projects

About

About the Milwaukee Estuary AOC Projects

This webpage includes information about 41 projects in the Milwaukee Estuary Area of Concern (AOC) that were selected to address the 11 beneficial use impairments (BUIs) for this AOC.

Project information is grouped according to the management action list under which the project will be completed:

• Contaminated sediment related BUIs
• Degradation of fish and wildlife populations BUI
• Loss of fish and wildlife habitat BUI
• Beach closings (recreational restrictions) BUI

Each tab includes a list of the projects, a map of project locations, the general status, who is leading the projects and a link to more information (if applicable).

Contaminated Sediment

Contaminated Sediment Projects

There are 11 projects in the Milwaukee Estuary AOC that are designed to address five beneficial use impairments that are due to contaminated sediment. These projects address the following impairments:

• Restrictions on dredging activities
• Degradation of benthos
• Fish tumors or other deformities
• Bird or animal deformities or other reproductive problems
• Restrictions on fish and wildlife consumption

Some projects have multiple remediation steps. Projects typically involve dredging and disposing of the contaminated material to remove it from the waterways and in some cases, the adjacent floodplains. In situations where the contaminated material cannot be safely removed, it’s sealed in place so the toxins no longer move through the environment.

EPA = U.S. Environmental Protection Agency
MMSD = Milwaukee Metropolitan Sewerage District
WRP = Waterway Restoration Partnership

Sediment Projects In Expanded AOC Boundaries

In 2008, the EPA approved expanding the geographic boundaries for the Milwaukee Estuary AOC because contributions of toxic substances from upstream sources had accumulated in the estuary since the original boundaries were drawn in the 1980s. The AOC boundaries were expanded north along the Milwaukee River into Cedarburg and west into Wauwatosa along the Menomonee and Little Menomonee Rivers to include specific project sites that contributed contaminated sediment into the waterways.

Dredged Material Management Facility Fish Removal Effort

The Milwaukee Metropolitan Sewerage District is partnering with the City of Milwaukee, Port Milwaukee, We Energies and DNR to build a new Dredged Material Management Facility (DMMF) in the Milwaukee harbor. The DMMF is an engineered structure to provide long-term, safe containment of contaminated sediment that will be removed from the Milwaukee Estuary AOC. It’s specifically designed to store contaminated dredged material to prevent contaminants from being released in the environment. Construction of the facility is anticipated to be completed in late 2026.

The goal of the fish removal effort was to remove as many fish as possible from the DMMF construction site to prevent trapping fish inside the DMMF when its outer containing walls were fully sealed. As the outer walls to enclose the perimeter of the DMMF were nearing completion in mid-August 2025, DNR crews caught and moved fish that were found inside the facility to other areas of the harbor. A summary report is available at the following link:

• Milwaukee Harbor Dredged Material Management Facility Fish Removal Effort, August 2025

More information about the DMMF can be found at the following websites:

• Milwaukee Metropolitan Sewerage District
• Waterway Restoration Partnership 

PFAS Sampling Results

PFAS (perfluoroalkyl and polyfluoroalkyl substances) are a large group of human-made chemicals that have numerous potential health and environmental implications. Although PFAS are not a contaminant of concern that can be addressed through the AOC project work due to the design of the federal AOC program, it is important to understand whether PFAS are present in the areas where remedial work will be occurring.

The DNR performed surface water and sediment sampling to determine if PFAS are present in areas that are targeted for potential remedial dredging as part of the AOC cleanup work. These sampling results are available at the following link:

• PFAS Sampling Results In The Milwaukee Estuary Area Of Concern (AOC) (includes maps and lab report)

Fish And Wildlife Populations

Fish And Wildlife Populations Projects

There are 16 projects in the Milwaukee Estuary AOC that are designed to address the Degraded Fish and Wildlife Populations Beneficial Use Impairment. These projects are designed to create or restore native habitat and breeding grounds tailored to the needs of specific species of fish and wildlife. Some projects have multiple steps.

Habitat Loss

Fish And Wildlife Habitat Projects

There are 11 projects in the Milwaukee Estuary AOC that are designed to address the Loss of Fish and Wildlife Habitat Beneficial Use Impairment. These projects are designed to create or restore native habitats and connect isolated habitats throughout the AOC.

Beach Closings

Beach Closings Or Recreational Restrictions Projects

There are three projects in the Milwaukee Estuary AOC that are designed to address the Beach Closings or Recreational Restrictions Beneficial Use Impairment. Beach closings occur due to unsafe levels of bacteria in the water. These projects are designed to improve water quality at the beaches through a variety of methods.