About the HHRAP

The Area of Concern 

Hamilton Harbour is a large embayment at the western tip of Lake Ontario. Hamilton Harbour was formally recognized as an Area of Concern (AOC) because of the effects of long-term discharges of industrial and municipal wastewater to the harbour and its tributaries, uncontrolled urban and rural stormwater runoff, and combined storm sewer/sanitary sewer system overflows.

The Hamilton Harbour AOC includes the waters of the harbour and Cootes Paradise Marsh and is fed by three main tributaries: Grindstone Creek, Redhill Creek, and Spencer Creek. The AOC also receives effluent from the Skyway Wastewater Treatment Plant, Dundas Wastewater Treatment Plant, and the newly upgraded Woodward Avenue Wastewater Treatment Plant.

What is an Area of Concern?

Areas of Concern (AOCs) are locations in the Great Lakes where water quality and ecosystem health have been severely degraded by local human activities.  Through the Great Lakes Water Quality Agreement, Canada and the United States identified 43 AOCs in 1987, including Hamilton Harbour.

What is a Remedial Action Plan? 

Each AOC has its own Remedial Action Plan (RAP), a locally developed, partnership-driven plan that guides restoration efforts. The goal of the RAP is to address historical environmental issues and ultimately remove the area from the list of AOCs, a process called delisting.  

The HHRAP identifies:

the harbour’s historical environmental concerns such as poor water quality, high levels of nutrient inputs to the waterways, bacterial contamination, and chemical contamination 
goals for restoring beneficial uses
actions to be taken, including those responsible for implementing these actions  
a monitoring and evaluation plan to track whether these actions have been effective

What is a Beneficial Use Impairment? 

A Beneficial Use Impairment (BUI) describes a human or ecological use of the ecosystem that has been degraded because of human-caused environmental problems. The Great Lakes Water Quality Agreement identified a list of 14 potential BUIs for Great Lakes AOCs.  

Each BUI has a status assigned to it: impaired, requires further assessment, or not impaired. Hamilton Harbour AOC has 11 of the 14 BUIs identified as either impaired or requires further assessment. For each BUI, environmental goals — called delisting criteria — are developed that describe the environmental conditions that will be achieved once all actions have been completed. The delisting criteria are used to guide restoration efforts and progress is measured against them. They can be updated from time to time as new information resulting from science, monitoring, and modelling is gained. 

When all actions have been completed and the delisting criteria have been met, a BUI status change is proposed in a redesignation report.  

Track the progress towards Hamilton Harbour’s remediation here!

History of Hamilton Harbour

Hamilton Harbour has a 150-year history of environmental damage due to industrial and urban development. Some of the challenges Hamilton Harbour faces include industrial contamination, deteriorating water quality, loss of wetland habitat, and degradation of fish and wildlife populations.  

Public access and viewing of Hamilton Harbour were once blocked by fences. Industrial practices along the southern shore led to the accumulation of harmful substances including PCBs (polychlorinated biphenyls), PAHs (polycyclic aromatic hydrocarbons), heavy metals (iron, zinc, and lead) and pesticides like DDT (dichlorodiphenyltrichloroethane). Exposure to these substances led to tumours, deformities, and reproductive issues in fish and wildlife. Dredged sediment from some areas were identified as hazardous waste. 

Hamilton Harbour and Cootes Paradise Marsh once supported abundant wildlife and a thriving commercial fishery. As industrial and urban development proceeded, Hamilton Harbour’s marshlands were either filled for industrial land or dredged for shipping. Excessive nutrients from several wastewater treatment plants and the watershed contributed to algal blooms and oxygen depleted waters, impacting the cold-water fishery. Along with overfishing and introduction of invasive species, the fish community changed slowly from large, long-lived predator species to pollution tolerant species that could withstand the conditions of Hamilton Harbour.   

Hamilton Harbour has unique site-specific features including being shaped like a bathtub with only a small drain to Lake Ontario through the Burlington Shipping Canal. Water exchange to the open waters of Lake Ontario is limited by this single connection, making Hamilton Harbour more vulnerable to inputs of nutrients and contaminants. 

HHRAP Partnerships

The Government of Canada and the Province of Ontario share the responsibilities for RAP progress and AOC remediation under the Canada-Ontario Agreement Respecting the Great Lakes Basin Ecosystem. The implementation of a RAP involves all levels of government, as well as partners from non-governmental organizations, academia, business and industry, Indigenous communities, and the public. The HHRAP is implemented by a group of partners called the Bay Area Implementation Team (BAIT). 

BAIT partners work together to develop and coordinate remedial actions to support the environmental changes needed to remove the remaining BUIs. 

A series of technical committees focus on identifying, planning, and reporting on the progress of remedial actions and associated environmental monitoring. Community engagement remains an important aspect of the HHRAP’s implementation and decision making.

BAIT Partners

How You Can Help!

A great strength of the HHRAP is the significant public involvement and support. We invite you to get involved and help remediate Hamilton Harbour: