Extreme weather events may give cause to rethink environmental due diligence systems

June 21, 2022 | Bryan J. Buttigieg

A recent heavy storm in Southern Ontario (labelled a “Derecho” by our meteorologists) caused extensive property damage over a wide swath of some of the most densely populated areas of the country. It served as yet another reminder of climate change predictions that extreme weather events are likely to increase in severity and frequency in the coming years. This in turn could well require a re-assessment of environmental due diligence systems to ensure that there is adequate assessment of and protection from foreseeable risks.

At the heart of our legal system prohibiting companies, officers, directors and other responsible persons from causing environmental harm is the expectation that due diligence must be exercised. In most cases, environmental liability can be minimised or avoided entirely if it can be shown that “all reasonable care” was exercised to prevent the particular event from occurring. Perfection in planning is not required. But planning that fails to account for what is “reasonably foreseeable” is not excusable. Due diligence systems cannot be static. They need to evolve and adapt to new information. Typically, we think of “continuous improvement” concepts as applying to learning from day to day operations, “near misses” and evolving industry knowledge. But this is by no means a closed list. New factors need to be considered as they become relevant.

So how should we think of an extreme weather event? On its face, one might be able to say that by being “extreme” the event is inherently unforeseeable. But as evidence mounts in support of the scientific predictions, what was once considered “extreme” may well become more common and thus foreseeable. If so, climate change and severe weather impacts will need to be considered when assessing the adequacy of an environmental due diligence program.

The implications for this are wide ranging. Building codes are already being revised to recognize that definitions of “100 year” and “10 year” storms are likely to soon become obsolete, if they are not already. Private interests will need to do the same.

Stormwater management is one obvious area of concern. Overflowing retention ponds could result in silt and sludge discharges that could impair the quality of watercourses and fish habitats. Septic systems may fail if groundwater levels change. Construction sites might need to reassess the adequacy of their run-off protection systems. All systems potentially impacted by heavy rain or flooding should be reviewed to assess whether they need to be upgraded to take into account any expected increases in quantity and frequency of rainfall. Failing to do so could well constitute a lack of due diligence.

Extreme wind events should be anticipated and appropriate measures put in place to minimize their potential damage.  These may result in dust and debris adversely impacting surrounding properties. The Supreme Court of Canada has ruled that fly rock from road blasting operations constitutes an environmental discharge that may cause an adverse effect. Would the same not apply to construction debris blown away during a severe wind storm? Is there now a duty to report this as an environmental “spill?” What steps were taken by the person with charge management and control of the site to ensure material was properly secured against such a storm? Again, due diligence requires evidence that the likelihood of such events was considered in advance and that reasonable precautions were taken to prevent the adverse effects from occurring.

Areas not previously considered at risk for forest fires should be reassessed. Can a facility be safely shut down in the event of a forest fire evacuation and will doing so create any risks of harm to the natural environment? Are any infrastructure upgrades advisable? If not, is there adequate evidence to document that the decisions made were reasonable in light of the most up to date information?

The possibility of lengthy power interruptions should not be ignored. Will sudden shutdown of equipment result in unacceptable emissions? Does pollution control and monitoring equipment need to be kept operational even during lengthy power failures? Is backup power generation required? Does that backup power create its own environmental concerns such as noise and other emissions? Will restarting equipment create any environmental issues?

Ultimately, responsible persons will need to review all aspects of their infrastructure and operations to assess whether existing due diligence is sufficient to deal with what is now clearly a foreseeable risk of more severe and more frequent wind, water and fire related weather events. What was once considered “extreme” may well no longer be so in the eyes of the law.


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