Nipigon Bay

About the Nipigon Bay AOC

Nipigon Bay is situated at the northernmost point of Lake Superior. The Nipigon Bay Area of Concern encompasses the majority of Nipigon Bay and a portion of Lake Superior’s largest tributary, the Nipigon River. 

Pollution from industrial and wastewater sources in both Nipigon and Red Rock, upstream hydro-electric development in Lake Nipigon and Nipigon River, and debris from past logging activities contributed to the degraded water quality and environmental health.

This led to Nipigon Bay being designated as an Area of Concern (AOC) in 1987. At this time, 7 of the Great Lakes Water Quality Agreement’s 14 Beneficial Use indicators of ecological quality were deemed as impaired and 1 required further assessment.


Concern included:

  • Upstream hydroelectric dams
  • The accumulation of wood fibre, bark, and other organic matter from historic log drives
  • Effluent inputs from municipal and industrial sources.
  • Mercury, PCBs from the mills, and wastewater from treatment plants

Issues relating to the concerns:

  • Negative pressures on fish populations
  • Loss of species biodiversity
  • Contaminated Benthos

Current Status & BUIs

All remedial actions have been completed and all beneficial uses have been restored.

Nipigon Bay is now being proposed for delisting. Environmental monitoring has confirmed that restoration targets have been achieved and beneficial uses have been restored. The final action is to confirm community support of the restoration of the AOC.


BUIs are currently identified as not impaired.

Tainting of fish and wildlife flavor (1995), restrictions on dredging activities (1995), fish tumours or other deformities (1995). degradation of fish and wildlife populations (2016), degradation of benthos (2016), eutrophication or undesirable algae (2016), degradation of aesthetics (2016), loss of fish and wildlife habitat (2016).

Work Completed to Date

The Nipigon Bay RAP program is now being facilitated by Lakehead University under the supervision and guidance of Environment Canada, the Ontario Ministry of the Environment, and the Ministry of Natural Resources. The Remedial Action Plan Team and Nipigon Bay Public Advisory Committee (PAC) is currently in the process of reviewing the remedial actions implemented to date and assessing the status of the remaining ecological impairments.

Over the past 30 years, many programs have been implemented at the Nipigon Bay AOC to enhance fish and wildlife communities, and to rehabilitate degraded aquatic and terrestrial habitat. Some of the major efforts undertaken include:

  • Improvements to the Township of Nipigon and Township of Red Rock’s municipal wastewater treatment, with the former bringing a secondary treatment facility into operation in 2012 and the latter completed in 2021.
  • Industrial changes to comply with stricter federal and provincial pulp and paper regulations in the mid-1990s, which led to improvements in water quality.
  • Enhancing fish populations, naturalizing aquatic habitat and creating additional spawning, nursery and feeding habitat through the following actions: naturalizing river flow near hydroelectric dams, restoring former wetlands and historic spawning grounds in the lower Nipigon River, rehabilitating Clearwater Creek to restore a severely degraded brook trout habitat, creating fish and wildlife habitat in the Township of Red Rock’s marina, and renaturalizing Kama Creek.


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