On the morning of September 14, 2023, at approximately 9:45 AM, Gerald Thompson was walking along the public sidewalk on 124th Street in Edmonton when he fell into an uncovered excavation trench that extended partially across the pedestrian pathway. The trench, measuring approximately 1.2 metres deep and spanning nearly the full width of the sidewalk, had been dug the previous afternoon by Westbrook Utilities Ltd., a contractor engaged by the City of Edmonton to repair a damaged water main beneath the roadway. At the time of the accident, no barriers surrounded the excavation, no warning signs had been posted, and the orange safety pylons that workers had placed the day before had apparently been displaced overnight, whether by wind, vandals, or some other cause unknown. Thompson, a 67-year-old retiree who walked the same route each morning to purchase his newspaper from a convenience store two blocks away, sustained a fractured hip, multiple contusions, and a torn rotator cuff in his right shoulder when he fell forward into the trench and struck the exposed pipe fittings at the bottom. He now seeks compensation from Westbrook Utilities Ltd., asserting that the contractor's failure to secure the excavation site constituted actionable negligence. Before the court can consider whether Westbrook breached any applicable standard, whether that breach caused Thompson's injuries, or whether Thompson is entitled to damages, it must first answer a threshold question that governs the entire claim: did Westbrook Utilities Ltd. owe Gerald Thompson a duty of care in the first place?
The duty of care inquiry stands as the gateway to every negligence action in Canadian common law, and its proper resolution determines whether the defendant can be held legally accountable for the plaintiff's loss at all. A finding that no duty existed terminates the lawsuit before any examination of the defendant's conduct, the causal chain, or the magnitude of the plaintiff's injuries. Conversely, establishing that a duty did exist opens the door to the subsequent elements of negligence analysis but does not, standing alone, establish liability. This lesson examines how Alberta courts determine whether a contractor performing excavation work in a public space owes a duty of care to members of the public who may encounter the work site, with particular attention to the legal tests, precedents, and policy considerations that shape this determination.
The modern Canadian framework for establishing a duty of care derives from the Supreme Court of Canada's landmark decision in Donoghue v Stevenson, as subsequently refined and adapted through Anns v Merton London Borough Council and, most significantly for Canadian purposes, Cooper v Hobart. In Cooper, the Supreme Court synthesized decades of jurisprudential development into a two-stage test that now governs duty of care analysis across all Canadian jurisdictions, including Alberta. At the first stage, the court asks whether the circumstances disclose a relationship of sufficient proximity between the plaintiff and the defendant such that, in the reasonable contemplation of the defendant, carelessness on its part might cause damage to the plaintiff. If proximity is established at this first stage, the court proceeds to the second stage, where it asks whether there exist residual policy considerations that ought to negate or limit the scope of the duty, the class of persons to whom it is owed, or the damages to which a breach may give rise. Understanding how these stages operate in practice is essential for anyone seeking to advise parties to construction-related injury claims or to manage the risk profile of excavation and similar work.
The first stage of the Cooper analysis itself divides into two branches, depending on whether the case before the court involves a category of relationship previously recognized as giving rise to a duty of care or whether the plaintiff is asking the court to recognize a novel duty. When the case falls within an established category, the proximity analysis is straightforward: the court simply confirms that the relationship between the parties fits the recognized pattern, and the duty is established without extended inquiry. When the case involves an arguably novel duty, the court must engage in a more robust proximity analysis, examining the full range of factors that might establish the closeness and directness of the relationship between the parties. The practical importance of this distinction cannot be overstated, because successfully fitting a claim within a recognized category eliminates significant uncertainty and litigation expense.
The relationship between a contractor performing excavation work on or adjacent to a public right-of-way and members of the public who travel on that right-of-way has long been recognized in Canadian and English common law as giving rise to a duty of care. This principle traces its origins to nineteenth-century decisions involving construction hazards on public roads and has been consistently affirmed in Alberta jurisprudence. The Alberta Court of Appeal's decision in Chicken v Hamilton provides early authority for the proposition that those who create hazards on public ways owe duties to travelers who may be imperiled by those hazards, and subsequent decisions have repeatedly applied this principle to contractors, property owners, and municipalities engaged in various forms of construction and maintenance work. In the contemporary framework established by Cooper, this body of precedent confirms that the contractor-pedestrian relationship in the context of excavation work fits within an established category of proximity, thereby simplifying the first-stage analysis.
Even where a case falls within a recognized category, it remains useful to understand the factors that originally led courts to recognize proximity in that category, because such understanding illuminates the boundaries of the duty and assists in analyzing cases that may approach those boundaries. The central proximity factors at work in the contractor-pedestrian relationship include the foreseeability of harm, the defendant's creation of a risk, the vulnerability of the plaintiff class, and the plaintiff's reasonable expectation that the defendant will take care to avoid causing injury. When Westbrook Utilities Ltd. excavated a trench that extended across a public sidewalk, it was manifestly foreseeable that pedestrians would approach the excavation, potentially without advance warning, and could fall into it if no protective measures were in place. The company directly created the risk that materialized: absent the excavation, the sidewalk would have remained passable and safe for ordinary pedestrian traffic. Pedestrians walking on public sidewalks occupy a position of inherent vulnerability relative to contractors who alter the physical environment of those sidewalks, because pedestrians cannot be expected to anticipate unexpected hazards and may lack the specialized knowledge to recognize construction-related dangers even when they become partially visible. Finally, members of the public reasonably expect that those who perform excavation work in public spaces will take basic precautions to protect passersby from falling into open trenches, an expectation grounded in common sense and reinforced by widespread industry practice and regulatory requirements.
The concept of foreseeability merits particular attention in the duty of care context because it plays a role at multiple points in the negligence analysis, and confusion about these distinct roles can lead to analytical error. At the duty of care stage, foreseeability is assessed at a relatively general level: the question is whether the defendant ought reasonably to have foreseen that carelessness on its part could cause harm to persons in the plaintiff's position. This is not an inquiry into the precise mechanism of injury, the exact identity of the plaintiff, or the specific magnitude of the loss. Rather, it asks whether harm to someone like the plaintiff was a reasonably foreseeable consequence of the defendant's activity if conducted carelessly. In the trench scenario, the foreseeability inquiry at the duty stage asks whether Westbrook ought reasonably to have foreseen that failing to secure an excavation on a public sidewalk could result in injury to pedestrians using that sidewalk. The answer is almost self-evidently yes: the risk of pedestrians falling into open excavations is precisely why safety barriers, warning signs, and covering plates exist as standard features of responsible excavation practice. It would strain credulity for a professional contractor to argue that pedestrian injuries from uncovered trenches lie outside the realm of reasonable contemplation.
Beyond the core proximity factors, courts sometimes examine whether the defendant assumed responsibility for the plaintiff's safety or whether the plaintiff reasonably relied on the defendant to exercise care. These factors, while more prominent in certain categories of duty (such as those involving professional services or voluntary undertakings), can reinforce the duty analysis in construction hazard cases as well. When a contractor obtains permits, establishes work zones, and undertakes excavation in a public space, it implicitly assumes a degree of responsibility for maintaining safe conditions within the area it has disturbed. Pedestrians who observe construction activity and proceed through or around a work site implicitly rely on the contractor to have implemented reasonable safety measures, particularly when no warnings indicate otherwise. This reliance may be especially pronounced when, as in Thompson's case, the pedestrian is following a habitual route and has no reason to anticipate that conditions have changed since the last time they traversed the area. The assumption of responsibility and reliance factors thus operate to strengthen, rather than merely duplicate, the proximity analysis grounded in foreseeability and risk creation.
Once proximity is established through the first stage of the Cooper analysis, the court proceeds to the second stage, where it considers whether residual policy considerations ought to negate or limit the duty that proximity would otherwise support. At this stage, the defendant bears the burden of demonstrating that compelling policy reasons warrant withholding the legal protection that the first stage would otherwise afford the plaintiff. Residual policy considerations are those not already accounted for in the proximity analysis; they involve broader concerns about the effect of recognizing a duty on the legal system, on other parties not before the court, or on society at large. Examples of residual policy considerations that courts have found persuasive in other contexts include the spectre of indeterminate liability to an unlimited class of potential plaintiffs, the interference with other legal regimes or legitimate social activities, and the potential for a flood of litigation that would overwhelm judicial resources. These considerations are evaluated not in the abstract but in light of the specific duty proposed and the class of persons to whom it would extend.
In the context of contractor liability to pedestrians injured by construction hazards on public ways, residual policy considerations do not operate to negate or limit the duty. The class of potential plaintiffs is inherently limited to those persons who physically encounter the hazard and suffer injury as a result, eliminating any concern about indeterminate liability to an open-ended population. Recognizing this duty does not interfere with any competing legal regime; on the contrary, it aligns with and reinforces the regulatory obligations imposed on contractors by the Alberta Occupational Health and Safety Act, the Alberta Building Code, and municipal permit conditions that routinely require barricades, signage, and covering of excavations. There is no spectre of uncontrollable litigation, because the factual requirements for recovery—actual injury caused by an actual construction hazard—naturally constrain the volume of claims. The legal system has absorbed duty claims of this nature for well over a century without adverse systemic consequences, and there is no reason to believe that continued recognition of such duties would produce different results now. For these reasons, the second stage of the Cooper analysis does not displace the duty that the first stage establishes.
Alberta courts have applied these principles in numerous decisions involving construction-related injuries, and the body of precedent provides substantial guidance for claim managers and legal practitioners evaluating potential liability. In decisions involving excavation and trenching work specifically, courts have consistently held that contractors owe duties of care to persons lawfully present on adjacent public ways and have not hesitated to find such duties established at the summary judgment stage when the facts support a straightforward proximity analysis. The existence of a prior contractual relationship between the contractor and a project owner or municipality does not displace or diminish the duty owed to third parties such as pedestrians; the contractor may owe concurrent duties to multiple parties, and the scope of each duty is determined by the nature of the relationship that grounds it. This point is sometimes misunderstood by contractors who believe that their obligations run only to the party that engaged them, but the common law has never accepted such a limitation on tortious duties arising from the creation of physical danger.
A related question that sometimes arises is whether the duty owed by a contractor performing work on behalf of a municipality differs in character or scope from the duty owed by an owner performing work on its own property. The answer, in most circumstances relevant to the trench scenario, is that the duty is substantially the same. While municipalities may owe certain non-delegable duties to maintain public ways in safe condition—a topic explored in related areas of tort law—contractors do not escape personal liability by pointing to the involvement of a public authority. The contractor remains directly liable for hazards it creates, irrespective of whether a municipality may bear concurrent or vicarious liability under a separate legal theory. This principle reflects the common law's focus on the conduct that gives rise to risk: one who creates a danger cannot avoid responsibility by observing that another party also had obligations to prevent it.
The temporal dimension of the duty of care deserves attention as well, particularly in cases like the one under consideration where the excavation was created on one day and the injury occurred the following morning. The duty of care that attaches to the creation of a hazard is not discharged merely by the passage of time; rather, it continues so long as the hazard persists and persons remain exposed to the associated risk. When Westbrook Utilities Ltd. excavated the trench at approximately 4:15 PM on September 13, 2023, and left the site at approximately 5:30 PM with the intention of returning to resume work the following morning, the duty of care remained operative overnight and into the next day. The overnight period was, if anything, a time of heightened rather than diminished concern, because reduced visibility during darkness and the potential for safety measures to be disturbed created conditions in which pedestrian injury was especially foreseeable. The duty that Westbrook owed Thompson at 9:45 AM on September 14 was precisely the same duty it had owed to any pedestrian from the moment the trench was excavated: the duty to take reasonable care to protect users of the public sidewalk from the risk of falling into the excavation.
Understanding the nature and content of the duty of care is essential not only for litigating or defending individual claims but also for managing operational risk in the excavation and construction industries. Contractors who appreciate that they owe an immediate, personal duty of care to pedestrians and other third parties from the moment they begin work are better positioned to design and implement site safety protocols that will both prevent injuries and reduce liability exposure. This understanding should inform training programs for site supervisors and workers, contractual allocation of risk between general contractors and subcontractors, and insurance procurement strategies. From the perspective of a claim manager reviewing a file like Thompson's, the relevant inquiry at the duty stage is whether the contractor's operations brought it into a relationship with the injured party of the kind that law has traditionally recognized as carrying obligations of care. Where, as here, the contractor created a physical hazard in a space to which the plaintiff had lawful access and which the plaintiff could reasonably be expected to traverse, the duty analysis will almost invariably favour the plaintiff.
In synthesizing the foregoing analysis, the following conclusions emerge for claim managers and practitioners evaluating potential claims arising from excavation-related pedestrian injuries in Alberta. First, the relationship between a contractor performing excavation work on or adjacent to a public way and members of the public who use that way falls within a well-established category of proximity, such that the first stage of the Cooper analysis is satisfied without the need for novel duty reasoning. Second, the proximity factors that ground this established category include the manifest foreseeability of harm to pedestrians, the contractor's direct creation of the risk, the vulnerability of pedestrians relative to the contractor's superior knowledge and control, and the reasonable expectation of pedestrians that those who disturb public ways will take precautions for their safety. Third, no residual policy considerations at the second stage of the Cooper analysis operate to negate or limit the duty; the class of potential plaintiffs is inherently circumscribed, no competing legal or social interests are jeopardized, and the legal system has long absorbed claims of this nature without adverse systemic effects. Fourth, the duty persists throughout the period during which the hazard exists and persons remain exposed to it, including overnight periods when work is not actively underway. Fifth, the duty is personal to the contractor and is not displaced by the involvement of a municipal or other public authority that may bear concurrent obligations. On the facts of Thompson's claim against Westbrook Utilities Ltd., the duty of care element of his negligence action is established: Westbrook owed Thompson a duty to take reasonable care to protect him from the risk of falling into the uncovered trench. With this threshold element satisfied, subsequent analysis can proceed to examine whether Westbrook's conduct breached the applicable standard of care, whether that breach caused Thompson's injuries, and what damages, if any, Thompson is entitled to recover.