Dam Failure Case Study: Cleveland Dam (British Columbia, 2020)

Cleveland Dam is a concrete structure located in North Vancouver, British Columbia, Canada. The 300-foot-high dam impounds the Capilano Reservoir, one of three major Metro Vancouver sources of drinking water for the Greater Vancouver region. On Thursday, October 1, 2020, in the early afternoon, the dam’s drum gate unexpectedly started to lower, releasing a torrent of water into the Capilano River. Members of the public located downstream were enjoying recreational activities such as hiking, fly fishing, picnicking, and visiting the local fish hatchery. No public warning was issued, and the population at risk was affected within minutes. There are reports that people had to self-rescue, and at least five individuals were swept downstream. One person was killed, and the body of a second person was never recovered.

After an investigation by the dam owner (Metro Vancouver), the primary contributing factor was deemed to be human error related to the programming of the control system for the spillway gate at the dam. Three workers were fired, a public education campaign was started, and an interim warning system was installed. A free public emergency mobile app for smartphones that can receive alerts from Metro Vancouver was also implemented. Public education is ongoing, and tests of the interim warning system are performed on a regular basis. The design of a long-term public warning system is now underway and is planned to be installed in 2025.