Risks of legal liability for stormwater management


Standard of care constantly evolving

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. Click to enlarge.
Toronto received more than 4,700 basement flood complaints during and after the July storm, totaling over $850 million in insurance claims across the GTA.

Toronto received more than 4,700 basement flood complaints during and after the July storm, totaling over $850 million in insurance claims across the GTA.

A negligent act, or omission, is one that breaches the required standard of care. The standard of care applicable to the design of infrastructure is likely to be the standard of care at the time of the design. That said, it is possible and perhaps more likely, that actions other than the “design” of infrastructure will be subject to a claim of negligence.

In one case where the deficiencies of the stormwater system were well documented, the defendant-municipality chose to avoid major infrastructure upgrades. It did, however, implement a bylaw requiring that downspouts be disconnected from the municipal sewer system. The municipality then failed to enforce the bylaw and was found liable for flooding, due to a failure of the municipal system. In that case, the failure to enforce the bylaw was found to be the inaction that determined negligence.

Since inspections, maintenance, repairs and other process decisions may be ongoing, they can be judged against a more recent standard of care. This may include considerations of changing information and climate change. Relying on outdated standards or processes can be negligent, if new information suggests that they should be reconsidered. This is the case even if the standards and processes were not negligent before the new information came to light.

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This does not mean that decision makers need to change all possible standards and processes and upgrade their entire infrastructure in light of climate change information. After considering the risks, it is acceptable to determine that a particular action or investment is not worth the cost. Such a determination is the essence of a policy decision. To minimize risk, however, governmental authorities should at least “turn their minds” to stormwater related standards, processes and infrastructure. This is particularly important if information suggests that there may be increased risk to persons or property.

An important tool for showing that the standard of care has been met is demonstrating that a defendant has met the standard practiced by similar parties. Simply following the actions of others will not necessarily prevent a finding of negligence. Coordination between parties with stormwater management responsibility, could assist in mitigating risk by setting a clear industry standard. In other words, it may be in the best interests of municipalities and other governmental bodies to work together and develop industry standards. These could be pointed to as evidence of the appropriate standard of care in future flooding cases.

Working towards legal risk management and minimization

Establishing processes for collecting and sharing new information can minimize the liability risk for governmental authorities. Information suggesting that there may be a risk to people or property should not be ignored or avoided. Authorities should ensure active, valid policy decisions are being made and documented with respect to stormwater management decisions and systems. Even where the authority decides that proposed upgrades or changes are too costly given identified risks and current resources, that decision should be documented. This demonstrates that the government authority had turned its mind to the matter. They should also consider policies and decisions that enhance flood control, including lot-level controls and homeowner education.

Lastly, they should work with consultants and other service providers to ensure they are considering the best information available, and develop best practices and industry standards with other stormwater management stakeholders.

A shared responsibility with shared risks

From a legal risk perspective, stormwater management is a shared responsibility. Municipalities, conservation authorities and provincial government can all impact the effective management of stormwater through their decisions, policies and procedures.

Since all levels of government can be sued for negligence in relation to their operational decisions, each has a strong incentive to consider its existing procedures and systems. Governments cannot escape liability for negligent actions of their employees, or contractors. Therefore, processes and practices for sharing relevant information should be in place. Service contracts can also include appropriate considerations related to climate change risk.

Additionally, consultants, engineers and other design professionals are all subject to legal liability for failure to take relevant information into account, or adapt to current, foreseeable conditions. Professionals who provide stormwater management services can potentially be sued by those who suffered harm and/or by governments that relied on their advice and actions. All parties involved in stormwater management have an interest in ensuring that sound, defensible decisions are being made and appropriate actions are being taken.

Private stakeholders also have roles to play in the management of stormwater and can be subject to legal liability, if they act negligently. Courts have determined that residents can be expected to participate in stormwater management, for example, by reporting known problems to authorities. In addition, it is possible that individual residents would potentially share in liability if they negligently contributed to the problem. This could include altering site grading so run-off flows toward, rather than away from basement foundations. However, governmental authorities cannot escape liability for making negligent operational decisions, just because property owners were also negligent.

Flooding-related class actions have the potential to bring multiple claims before a single court, conceivably resulting in large settlements, or cost awards. This highlights the need for governmental authorities to actively and collaboratively manage legal risks and work towards shared solutions where stormwater management is concerned. Taking appropriate action to identify and make suitable decisions based on risk is particularly important in light of predicted changes in our climate.

This article is provided for discussion and information purposes only and should not be considered legal advice.

Laura Zizzo, Travis Allan and Alexandra Kocherga are with Zizzo Allan Professional Corporation. This article appeared in ES&E’s July/August 2014 issue.

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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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