Executive Summary: Key Legal and Evidentiary Issues

• Appeal arose from dismissal of claims in negligence and nuisance over flood damage caused by a culvert failure.

• The appellant alleged the Public Guardian altered and obstructed Cherry Creek, damaging her downstream property.

• The trial judge misinterpreted expert evidence, wrongly concluding flooding was due to natural causes, not maintenance failure.

• The court failed to properly consider strict liability under the Water Act and misapplied the burden of proof.

• Lay witness evidence about the timing and cause of the culvert failure was largely ignored in favor of flawed expert assumptions.

• The appeal was allowed; the case was remitted for a full trial due to material legal and factual errors at summary trial.

Facts and outcome of the case

Background and property damage claims

Corine LeBourdais, the appellant, owns land downstream from a property administered by the Public Guardian and Trustee (PGT) of British Columbia. Both properties are located along Cherry Creek near Kamloops. In 2012, the PGT replaced a culvert on its property after a prior washout. On May 4, 2017, that culvert again failed and was displaced downstream, allegedly obstructing the creek and diverting its flow into the appellant's property.

The appellant claimed that this obstruction initiated a chain of events leading to severe erosion, creation of avulsion channels, and long-term damage to her land and structures. She brought a civil action in negligence and nuisance against the PGT, the Province of British Columbia, and the Thompson-Nicola Regional District. The claims against the Province were dismissed by consent, and those against the Regional District were dismissed by the court. The focus of the litigation became the liability of the PGT.

Summary trial and initial dismissal

At a five-day summary trial in August 2024, the Supreme Court of British Columbia dismissed the appellant’s claim. The trial judge found she failed to prove the PGT had acted negligently or caused a nuisance. Central to the judgment was expert evidence presented by the PGT’s engineer, who attributed the flood damage to record regional flows due to snowmelt and high temperatures—arguing the culvert’s failure was irrelevant to the resulting property damage.

The trial court accepted this expert view and dismissed the appellant's factual claims that the culvert’s displacement occurred before peak flooding. The court also rejected arguments that the PGT had failed in its statutory duties under the Water Act and the Water Sustainability Act.

Appeal and key findings

On appeal, the court determined that two critical errors warranted intervention. First, it held that the trial judge misapprehended the expert evidence. The PGT’s expert had provided peak flow estimates based on nearby streams, but under cross-examination admitted he lacked specific flow data for Cherry Creek on May 4, the day the culvert failed. Nonetheless, the trial judge treated the peak flow estimate as if it applied to May 4, and based key findings on that mistake.

Second, the court found that the trial judge failed to properly analyze the statutory claim under section 21 of the Water Act (and its successor provision under the Water Sustainability Act), which imposes strict liability on those altering stream flows. The judge incorrectly placed the burden on the appellant to prove that the PGT’s work failed to comply with the regulation, rather than requiring the PGT to prove it had exercised reasonable care.

The appellate court also observed that the trial judge failed to meaningfully consider uncontradicted lay evidence from the appellant and other witnesses, who testified that the culvert had failed and was obstructing flow prior to any significant flooding.

Outcome of the appeal

The court allowed the appeal, set aside the summary trial decision, and remitted the matter for a full trial. It concluded that the errors—both legal and evidentiary—undermined the trial judge’s core conclusions. No damages or costs were awarded as part of this appellate ruling, and the matter will now return to the lower court for proper adjudication based on a full evidentiary record.