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Risks of legal liability for stormwater management

Thousands of commuters were stranded in Toronto on July 8, 2013 after close to 140 mm of rain fell in just a few hours. Photo by mark.watmough via Flickr, CC BY 2.0.

By Laura Zizzo, Travis Allan and Alexandra Kocherga

The rise in extreme weather events and resulting strain on municipal infrastructure has brought increased attention to stormwater management. Recent class action lawsuits related to flooding, have been brought against municipalities, conservation authorities and the Province of Ontario, demonstrating the legal risk associated with stormwater management. These class actions alleged systematic problems.

It is important for governments and other stakeholders to consider potential legal liability concerns due to increased flooding risks, and to work towards minimizing liability where possible.

Many stakeholders including municipalities, conservation authorities and provincial government, make infrastructure investments, management decisions and operational policies that have a direct impact on the safe and effective management of stormwater. In the absence of a clear set of best practices and standards, many have important unanswered questions about the appropriate level of service that should be provided. This uncertainty is enhanced by increased municipal development and climate change, which may create new costs and technical challenges for existing systems. In some cases, the scientific and technical foundations upon which management decisions are being made may no longer be valid, due to development and climate change influences. Failing to account for these could lead to unanticipated, or unacknowledged, decreases in service levels.

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It is not only governmental authorities that need to be aware of legal risks. Contractors, private landowners and residents all have roles to play in the management of stormwater and potential legal liability. A better understanding of potential legal liabilities can assist those involved in stormwater management to ensure thoughtful and diligent management practices.

Beware of negligence

Legal obligations related to stormwater management are determined by both legislation and common law, which is judge made law determined through the courts. Legal changes in Ontario and some other jurisdictions mean that common law causes of action against municipalities relating to flooding, are primarily grounded in negligence.

In establishing negligence, a plaintiff must show, on balance, that the defendant owed them a duty, breached the applicable standard of care, caused the harm and could reasonably have foreseen the injury. These tests are determined on a case-by-case basis and could be impacted by climate change and other considerations.

A recently launched and subsequently withdrawn class action in Illinois, invited a court to consider whether municipalities were negligent in preparing for severe rainstorms in light of climate change. This action may signal the beginning of explicit references to climate change in these types of cases.

Governmental policies vs. operations

Since governments have to make tough decisions about budgeting resources and balancing priorities in the public interest, courts are reluctant to find negligence with respect to policy decisions. Courts generally see policy decisions as part of the democratic process, and defer to the judgment of elected officials. However, not all decisions are exempt. The courts have acknowledged that “operational” decisions, actions and inactions, can be subject to judicial scrutiny for negligence claims.

In order for a decision to qualify as “policy,” the decision maker must have specifically considered the issue at hand and made a conscious decision to act, or not to act, based on social, political and economic factors. Simply failing to consider an issue is unlikely to be considered a policy decision. An operational decision, by contrast, relates to how a municipality executes, or carries out, a given policy decision.

Governmental authorities can be held liable for flooding damage that results from a negligent operational decision. Changing information, including that related to climate change, could increase the number and size of lawsuits. For example, residents receiving stormwater management services are owed a duty. They may become more vulnerable, particularly if avoidable potential impacts of climate change are reasonably foreseeable. A valid policy decision, as opposed to an operational decision, can negate a finding that a duty of care exists and prevent a finding of negligence.

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  1. Big elephant in the room is: drainage water can not get to lake Ontario basin. Sad no one wants to address the blockages done by approved developments by municipalities and conservation authorities. No excuse 10 acres of once flood plains land filled and placed high rised condominiums .Right at the mouth of the Etobicoke Creek. Just one of many.


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