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A Primer on Wetland Offsetting in Ontario

Practices, Policies and Resources

Mer Bleue Bog, Ottawa © National Capital Commission CC BY-NC-ND 2.0


Ontario has lost more than 72 percent of wetlands south of the Canadian Shield, and the losses continue. Furthermore, according to the 2021 Ontario Auditor General’s report on the environment, the Government of Ontario has quietly abandoned the Wetland Conservation Strategy for Ontario 2017–2030. A key threat to Ontario’s remaining wetlands is land conversion for development, with the practice of wetland offsetting emerging as an increasingly popular strategy to compensate for wetland destruction or degradation.

Wetland offsetting is risky business. It is seldom successful in fully compensating for wetland loss. While it may make sense in situations where damage is unavoidable, it should always be considered only as a last resort and approached with extreme caution. Currently, however, local planning authorities are operating in the absence of provincial guidance on offsetting, and in many cases without a clear sense of the risks inherent in the practice.

Sifton Bog Environmentally Significant Area, London © Noah Cole

This primer will introduce the basics of wetland offsetting practice and policy, including additional resources for those who want to learn more. It is organized into four sections:

1. Laying the Groundwork

This page provides a “crash course” on what wetland offsetting means and the key risks associated with it.

Least bittern © Caleb Putnam

2. Evaluating Policy

This page introduces a ten-point framework to evaluate the strength of wetland offsetting policies based on recommendations and considerations from a range of experts.

Black tern © Brian Baquial

3. Exploring Policy Examples

This page links to four offsetting policies created by conservation authorities in Ontario, highlighting their significant strengths and opportunities for improvement.

Greenbelt © Tim Hagen

4. Expanding Your Horizons

This page provides resources to delve even deeper into the topic of wetland offsetting.

Milburn Wetland © Paul Heaven