British Columbia·Video

Human error 'clearest contributing factor' in deadly Cleveland Dam incident: preliminary report

A preliminary report has found human error was "the clearest contributing factor" in a deadly incident at the Cleveland Dam in North Vancouver, B.C., on Oct. 1, the regional district said Thursday.

2 people downstream were killed when dam unexpectedly released torrent of water into Capilano River on Oct. 1

The Cleveland Dam was down to a trickle on Oct. 5 after a sudden surge of water killed several anglers downstream several days earlier. (Yvette Brend/CBC News)

A preliminary report has found human error was the "clearest contributing factor" in a deadly incident last week at the Cleveland Dam in North Vancouver, B.C., the regional district said Thursday.

Two men, a father and son, were killed downstream when the spillway gate opened unexpectedly during maintenance on Oct. 1, releasing a freezing torrent of water into the Capilano River.

"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 commissioner Jerry Dobrovolny said in a statement.

"Metro Vancouver takes responsibility for this mistake and our deepest sympathies go out to those affected by the tragic loss of life."

The man, who was an artist, and his son, 27, were among five anglers who were swept away by the gush of water after the dam opened without public warning. The father's body was discovered later that day, but the remains of his son have not been found.

The other three anglers escaped the river on their own or were rescued.

The river had risen by more than three metres in a matter of minutes, surging through the popular fishing spot. One witness who was having lunch on a viewing platform over the water said the scene of fishermen scrambling for the banks was like "all hell" breaking loose.

WATCH | Witness recounts watching torrent of water rush down the Capilano River: 

Witness recounts watching torrent of water rush down the Capilano River

4 years ago
Duration 1:07
'Sounds like a thunderstorm': William Joseph recorded video from the shore as water from the Cleveland Dam rushed down the river.

Alarm idea previously nixed

The report's findings come amid calls for Metro Vancouver to make the dam safer. There is no siren or alarm system to warn people if the dam malfunctions.

Such a warning system was never installed because of concerns the noise would annoy residents in the Glenmore and Grouse Woods neighbourhoods less than 400 metres away, according to engineering reports from the early 2000s.

"That's ridiculous," said Mike Hanafin, a hiker who saw the water surge and anglers scramble from a viewing platform above the river. 

Anglers fish along the banks of the Capilano River one day after the Cleveland Dam released an unexpected rush of water that sent many people who had been fishing running for their lives. (Ben Nelms/CBC)

Hanafin said he wants to see warning sirens strategically placed throughout the canyon that would sound if the dam were unexpectedly opened, rather than for controlled releases. He said a siren likely could have prevented the tragedy last week.

 "If it annoys local residents once every 20 years, that's not a big price to pay," he said.

Geoff Kershaw, who regularly fishes at the Capilano River, said an alarm would help, but more should be done.

"There has to be some fail-safes in place that would at least require some form of human intervention before the dam is ever opened that quickly or that wide," he said.

History of malfunction

The dam, built in 1954, has a history of malfunctioning. Inspection reports from WorkSafeBC detail two errors that left people in danger in 2002.

In one instance that year, four fishermen were left stranded on a shrinking island in the middle of the river after the level of the waterway suddenly rose by more than a metre. In the other, a valve controlling the dam's gate opened by mistake while a film crew was working directly below. The Workers' Compensation Board said the crew could have been killed.

On Thursday, Metro Vancouver said the 2002 errors happened while the district was in the process of upgrading the spillway gate. The gate was upgraded from the old mechanical system to a new, fully automated control system later that year.

Dobrovolny said the inadvertent opening this month was the first since the upgrade.

The district said Thursday a formal public safety assessment of the dam was finished earlier this year, taking into consideration the hazards that come with people using the river downstream. The statement said the review found the dam "demonstrated consistency with industry best practices."

With files from Yvette Brend and Micki Cowan