Just the Facts Please! A Discussion of Limitation Periods for Environmental Claims

  • April 06, 2023
  • Talia Gordner, partner, Ralph Cuervo-Lorens, partner, and Andrea Arbuthnot (summer student), McMillan LLP

From having their own special limitation period exception to the distinct risks associated with continuing environmental torts, environmental claims are in a class of their own. The uniqueness of environmental claims arises in part from the fact that the subject matter of the loss or damage is often literally hidden beneath the surface of the land and requires expert investigation to not only discover the contaminants but to delineate them, determine their source and assess the extent of their impacts. This means that environmental contamination and consequential impacts may be discovered years, if not decades, after the initial contaminating incident. This circumstance is further complicated by the fact that often the responsible parties are long gone by the time a party realizes they have suffered damage.

While all claims are subject to limitation periods of some kind providing a deadline by which a party must commence a legal proceeding, the uniqueness of environmental claims requires special consideration and discussion. This Bulletin considers how limitation periods apply to environmental claims in Ontario and how to reduce the risk of missing one.

Limitation Periods in Ontario

The Ontario Limitations Act, 2002 (the “Limitations Act”) provides a basic two year limitation period to commence a legal proceeding after a claim is “discovered” (see more on this key term below) and a fifteen year ultimate limitation period from the day on which the act or omission on which the claim is based took place.[1] However, there are several exceptions to the ultimate limitation period.

One of these exceptions is found in section 17 of the Limitations Act, which provides that “there is no limitation period in respect of an environmental claim that has not been discovered”.[2] Why does this exception exist? It is very common for contamination to remain hidden below the surface before it is discovered years (even decades) later. The legislature determined that it would be unfair for parties impacted by such hidden contamination to be unable to recover their losses from the party who caused them harm because they did not know about or could not find the contamination (or its source) for over 15 years. As a result, recently discovered “legacy” contamination from decades prior is often the subject of environmental proceedings.

While environmental claims will not be automatically statute-barred if the contaminating incident or events occurred over 15 years earlier, thanks to section 17 the two year basic limitation period will start to run when a claim is discovered.