VANCOUVER -- The "clearest contributing factor" to a B.C. dam release that swept away at least five people and killed at least one was "human error relating to programming the spillway at the dam," a Metro Vancouver official says.

Jerry Dobrovolny, Metro Vancouver's chief administrative officer, told a committee meeting Thursday that the regional government has started an investigation into the torrent of water that swept down the Capilano River in North Vancouver last week, but said early results show it is related to a computerized system that was responsible for several uncontrolled water releases in the early 2000s.

“While the review continues, we can now confirm that the clearest contributing factor was related to programming of the control system for the spillway at the Cleveland Dam,” Dobrovolny told Metro Vancouver board members at the Water Committee.

“Metro Vancouver takes responsibility for this mistake,” he said, “And our deepest sympathies go out to those affected by the tragic loss of life.”

A CTV News investigation earlier this week documented a series of dam releases going back to the 1970s that stranded fishermen, swept people out to sea and may have been connected to the death of an eight-year-old girl.

In 2002, a Worksafe BC report into an uncontrolled release ordered Metro Vancouver to do a risk assessment and put in various safety measures, including an alarm system to warn people about any rising water levels.

Last week, Dobrovolny said there had been no alarms put on the dam.

“There have been reports in the media about similar incidents in the early 2000s,” he said, adding that when the dam was first built, a mechanical system was used to operate the gate. After some concerns with that system, it was replaced with a computerized one.

“When the computerized system was commissioned around 2002, we had several events of uncontrolled release as that new system was being commissioned," he said. 

“It’s now been almost two decades since we had a large uncontrolled release similar to this."

He said he believed that Metro Vancouver was in line with WorkSafeBC orders and with the most recent inspections of the dam.

“One that has been discussed is a public warning system to address and monitor downstream flows,” he said. “A decision was made not to for a number of reasons. The river can be quite high often during the winter months.”

He said the agency will lower the level of the Capilano Reservoir and leave the gate down during the winter months and will be locked off.