'Mistakes can happen': Human error to blame for Île-aux-Tourtes bridge closure

Transport Minister Francois Bonnardel can't say when the Île-aux-Tourtes bridge will reopen, but on Friday he acknowledged that human error is to blame for the structural issues that led to its shutdown a day earlier. 

Dozens of steel rods meant to reinforce the aging structure were damaged during regular maintenance work.

One of those rods was severed on April 30 and a lane was closed as a result.

"Mistakes can happen," the minister said. "I don't want to blame anyone, but we're working with humans."

Another rod was damaged on May 12, leading to a second lane being closed. Inspections revealed that about 40 rods were in bad shape.

Following a series of meetings held earlier this week, the Transport Ministry decided to close down the bridge.

The Île-aux-Tourtes bridge is a vital link for commuters, connecting Montreal's West Island to Vaudreuil-Dorion via Highway 40. In peak times, about 87,000 vehicles use the bridge daily, including 10,000 trucks. The closure is causing traffic nightmare for drivers.

Bonnardel apologized for the inconvenience "that they are experiencing since last night, and they will continue to experience for a few days." 

He did not provide a more specific timeline.

"I remain an eternal optimist, and I can't imagine the bridge being closed long term," Bonnardel said. "[But] it is true that currently, we cannot give you a specific timeline."

For now, traffic is being diverted by Highways 20 and 30. Until the bridge reopens, the ministry is cancelling the toll on Highway 30 and rides on the Vaudreuil-Hudson Exo line will be free. 

"Closing the bridge was the only responsible decision that could be taken," the minister said. "What I can tell you right now is that work will be carried out 24/7."

The minister insists the bridge is safe, and there is no risk of it collapsing. 

The structure, built in 1965, has had to undergo costly repairs in recent years. By 2018, the government had already injected $87 million to maintain the bridge and another $45 million was expected to be spent by 2028.

The Quebec government is planning to replace the bridge by 2027.

'Could have been avoided,' expert says

It is "very rare" for human error to be blamed for damage to critical infrastructure, said Lan Lin, a professor of engineering at Concordia University who has extensive practical experience in the design of buildings and bridges.

There have been cases where human error has led to disaster, she said, citing the 2007 collapse of the  I-35W Mississippi River bridge that killed 13 people and injured 145 others.

"I believe for this situation we should feel kind of lucky somehow because no one has been injured," said Lin.

Damaging load-bearing rods on the Île-aux-Tourtes bridge is a serious mistake, and closing the bridge for a careful investigation was the only option, she said. 

"I believe it could have been avoided," said Lin, estimating it will take at least a month for crews to carry out inspections and repairs.

The Île-aux-Tourtes bridge's design life may have been 75 years, Lin said, but with proper maintenance, such bridges can last 100 years.

"For any bridge, if it's well designed and well maintained, the service life will be beyond its design life," she said.