METRO Vancouver Commissioner Jerry Dobrovolny, releasing the preliminary findings of the circumstances surrounding the uncontrolled release of a large volume of water into the Capilano River on the afternoon of October 1, said on Thursday: “While the review continues, we can now confirm that the clearest contributing factor was human error related to programming of the control system for the spillway gate at the Cleveland Dam. Metro Vancouver takes responsibility for this mistake and our deepest sympathies go out to those affected by the tragic loss of life.”
Metro Vancouver said it is committed to ensuring that this type of event never happens again. As a result of this incident, it is implementing system enhancements including exploring the viability of implementing an improved public warning system and increasing monitoring downstream of the dam. Further, it is bringing in expert advisors, both consultants and peer reviewers, to assess current practices and procedures and provide independent advice on opportunities to further strengthen its already robust operations and maintenance systems.
Metro Vancouver said it will also be lowering the spillway gate, which will stay in the lowered position through the winter, with water from the lake flowing over the spillway and into Capilano River.
“Following technical recommendations by experts, Metro Vancouver upgraded the Cleveland Dam spillway gate from a mechanical to fully automated control system in 2002 and there have been subsequent upgrades. Metro Vancouver has not experienced a similar unintended release of water in almost two decades,” said Dobrovolny. “We are entirely compliant with all related WorkSafeBC orders and requirements.”
Metro Vancouver said the 2002 WorkSafeBC items recently featured in the news happened during the process of commissioning the new system, causing an unplanned high flow release, which was subsequently fully remedied.
Metro Vancouver said it conducts dam safety reviews every seven years, which include an assessment of public safety measures. This was most recently completed in 2016, and was performed by an independent technical expert as part of regulatory requirements of the Provincial Dam Safety Program. Earlier this year, a formal public safety assessment of the Cleveland Dam was completed, taking into consideration the nature of the dam and the river system, the geography of the space, and potential hazards considering downstream users and activities, and demonstrated consistency with industry best practices.