Calgary Alberta - After blasting the federal government and Canadian Pacific in a train derailment and partial bridge collapse in Calgary last year, Mayor Naheed Nenshi is welcoming a report released Wednesday that blamed unprecedented flood water for the incident.
 
Railway Investigation Report R13C0069 by the Transportation Safety Board of Canada (TSB) indicated the Bonnybrook bridge over the swollen Bow River gave way beneath a Canadian Pacific Railway train on 27 Jun 2013 as the city was trying to recover from high water that had washed over many neighbourhoods just days before.
 
Six tank cars, of which four were carrying highly explosive, toxic liquids, 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.
 
During the incident, Nenshi had strong words for the rail giant and for the federal government.
 
He questioned whether layoffs decreasing the number of inspectors with CP Rail had played a role.
 
He had also called for improved regulations on trains through the city, and noted that municipalities are powerless to regulate railways, as they fall under federal jurisdiction, yet "it's my guys down there risking their lives to fix it."
 
But in an e-mailed statement issued Wednesday after the report was released, Nenshi said he was pleased to now have "clear data" about what led to the bridge failure and train derailment.
 
He also thanked the TSB for its "careful analysis of the bridge, inspection procedures, and the unified response from the City of Calgary Fire Department and CP."
 
"Despite the frustration and danger the situation represented for our community, I am pleased to know that the TSB is confident that the work of our fire department was top-notch during the emergency," Nenshi added.
 
"I am also pleased to know that, while CP's inspection practices prior to the incident exceeded Transport Canada requirements, CP has revised its bridge inspection practices and inspector training program, and that it is investing in research to better inspect aging rail bridges."
 
Ward 9 Coun. Gian-Carlo Carra, who represents that area of the city, had similar comments about the report.
 
"I'm pleased to hear that the CPR was exceeding standards with regards to inspections and that they've subsequently raised the bar even further," Carra said in a statement.
 
"I'm deeply gratified with the TSB's confirmation that Calgary's emergency response was second to none."
 
Fowler said inspections conducted on the 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 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.
 
In addition, Bonnybrook is one of five bridges that has been outfitted with a new SENSR automated technology, which provides real-time data to CP Rail's control centre on load, vibration, and impact at any given time, said spokesman Martin Cej.
 
"We've been using that for the past 12 months or so. The roll out has been so successful, we will be rolling out to eight more bridges," Cej added.
 
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."

Bill Graveland.