Report says ‘unprecedented’ flood at root of Calgary bridge failure

The Transportation Safety Board says unprecedented flood water was to blame for a derailment and partial bridge collapse in Calgary last year.

CALGARY — The Transportation Safety Board says unprecedented flood water was to blame for a derailment and partial bridge collapse in Calgary last year.

The Bonnybrook bridge over the swollen Bow River gave way beneath a Canadian Pacific Railway train (TSX:CP) on June 27 as the city was trying to recover from high water that had washed over many neighbourhoods just days before.

Six tank cars carrying a petroleum dilutant teetered on the failing bridge. They were unloaded and removed over two days and never went into the river.

“Unprecedented flooding of the Bow River was a major factor in this bridge failure. The bridge handled several major floods for over a century, but the river was not to be denied last June,” said George Fowler, a civil engineer who conducted the investigation.

“Intense, unprecedented floodwater flow had attacked the shale, sandstone, bedrock and clay pier foundation – eroding and undermining it.”

Fowler said the bridge, which was built in 1897 and expanded in 1912, had been properly inspected by Canadian Pacific Railway.

“Inspections conducted on the Bonnybrook bridge exceeded regulatory requirements during the flood. Visual observations of the rail and track alignment, and service, would normally detect deviations. However, in this case, such inspections did not provide warnings of the sudden bridge failure,” said Fowler.

“This bridge has been around since 1897 and in that time it survived several significant flooding events,” he added. “There was no reason to believe this event would be any different.”

Fowler said the true extent of the damage to the foundation wasn’t known until repairs were underway two months later.

Railways fall within federal jurisdiction and are responsible for their own inspections. Fowler said CP has revised its bridge inspection practice and its inspector training program and is investing in research into early detection of erosion at railway bridges.

CP dismantled the Bonnybrook Bridge in the autumn of 2013 and work on a new span was completed in April of this year. The damaged bridge pier has been replaced and reinforced with a new foundation.

An official with CP Rail welcomed the final report. President and chief operating officer Keith Creel said he agrees with the safety board that the City of Calgary’s command structure worked well to get the site secure and to help remove the derailed cars.

“Our relationship with the first responders of the City of Calgary allowed us to co-ordinate efforts to work quickly and to safely remove the cars from the bridge,” said Creel.

“CP is grateful to the Calgary Fire Department and other first responders and thanks them for their skill, effort and commitment to public safety.”

Just Posted

Trudeau’s cabinet choices have domino effect on House of Commons work

OTTAWA — As Prime Minister Justin Trudeau settles on his choices for… Continue reading

Protesters say Alberta bill would make it harder to access some medical services

EDMONTON — Opponents of a private member’s bill that calls for more… Continue reading

Freeland’s imprint of foreign affairs remains even if she’s shuffled: analysts

OTTAWA — Whether or not Prime Minister Justin Trudeau shuffles her to… Continue reading

Saskatchewan government considers funding first supervised consumption site

SASKATOON — Saskatchewan’s health minister says the government will consider whether to… Continue reading

Thousands fill City Hall Park for Red Deer Lights the Night

With the flip of a switch, downtown Red Deer was filled with… Continue reading

Central Albertans help families during holidays with Christmas Wish Breakfast

It takes a community to help a community. And Sunday morning at… Continue reading

Your community calendar

Nov. 19 The Mountview Sunnybrook Community Association will hold its AGM at… Continue reading

‘Ford v Ferrari’ speeds to No. 1; ‘Charlie’s Angels’ fizzles

NEW YORK — “Ford v Ferrari” put its competition in the rearview,… Continue reading

Teen with cancer whose viral video urged Canadians to vote has died, uncle tweets

WINNIPEG — A terminally ill cancer patient who recorded a video from… Continue reading

Five things to watch for when Trudeau shuffles his cabinet this week

OTTAWA — Prime Minister Justin Trudeau is set to unveil his new… Continue reading

Closing arguments begin in B.C. case launched in 2009 over private health care

VANCOUVER — A framed iconic photo in Dr. Brian Day’s office shows… Continue reading

Rowing Canada, university investigate celebrated coach for harassment, abuse

VANCOUVER — Lily Copeland felt she had found her purpose in life… Continue reading

MacKinnon scores OT winner, Avs recover from blowing late lead to beat Canucks

VANCOUVER — Nathan MacKinnon scored his second goal of the game 27… Continue reading

White House urgently ramps up push for drug cost legislation

WASHINGTON — The White House is ramping up its push to get… Continue reading

Most Read