"Someone needs to be held responsible," said New Democrat transport critic Olivia Chow.
"The federal government shouldn't wash their hands of it and the (Transportation Safety Board) is not the right venue. It really is Transport Canada."
Four petrochemical-laden rail cars derailed on a bridge over the Bow River last week when a Canadian Pacific Railway freight train was passing over the span. A preliminary investigation has determined one of the four piers that support the bridge sagged when the river swelled during heavy flooding.
CP (TSX:CP) said it inspected the bridge 18 times after the flooding began, but it was unsafe to send divers down to check below the water's surface.
"We would normally have probably put divers in to inspect, but the current was too fast," CP CEO Hunter Harrison said last week. "It's so murky, you couldn't do an appropriate inspection.''
Harrison said it would have been "jeopardizing commerce'' to hold back trains until divers could get in.
Calgary Mayor Naheed Nenshi and Conservative MP Deepak Obhrai, who represents the riding where the bridge failed, expressed anger with CP.
Chow said the federal government needs to investigate the failure under provisions of the 2011 Railway Safety Act, which came into force last May. Companies that break the rules can be fined up to $1 million and executives can be fined $50,000 or face jail time of up to six months.
Chow said the act requires the government to ensure railways are doing a proper job of monitoring safety procedures.
"Under the (safety management system), they're supposed to investigate if the company is following the rules or not and of course there should be an investigation," she said.
"But that requires investigation. That requires more staff. It requires a government willing to take its responsibility seriously."
"Any time the safety management system is broken, there need to be consequences. There needs to be punishment. If not, then it's not worth the paper it's written on."
Transport Canada spokeswoman Karine Martel said the government will wait for the findings of a Transportation Safety Board investigation into the accident.
"Once they have completed their investigation and released their report, Transport Canada will not hesitate to take appropriate action," she said.
A Transportation Safety Board spokeswoman said the board won't conduct its investigation specifically in light of the new legislation.
"We do not intend to review changes made in the 2011 Railway Safety Act," said Julie Leroux.
"That being said, if we find actions taken or not taken that contributed to the Bonnybrook bridge pier foundation failure, we will identify (them) as inadequate or a safety deficiency."
Board investigations often take longer than a year.
Transport Canada has issued an emergency directive for all CP trains to restrict their speed to 17 kilometres an hour over bridges that might have been weakened by flooding. The directive holds until the structures have been fully inspected.
Last week's accident was safely resolved without injury to rail crews or harm to the river.
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