CALGARY — Calgary’s mayor has a lot of serious questions for CP Rail after a bridge across the Bow River failed and railcars carrying oil products derailed.

Naheed Nenshi said during a news briefing THursday he wants to know why the bridge was last inspected on Saturday when water on the river was still at record levels.

"Certainly once this crisis is over, I'll be looking for a lot of answers from a lot of people," he said Thursday at an update on the bridge collapse.

"When was that bridge inspected? Why was it not inspected after Saturday? Remember on Saturday the Bow River was still running higher than anyone had ever seen in their lifetimes," Nenshi said.

"I'll be very blunt. I'll probably get in trouble for saying this. We've seen a lot of people lose their jobs at CP over the last year. How many bridge inspectors did they fire?"

Railways are under federal jurisdiction and Nenshi said that’s been a point of contention for municipalities who are powerless to regulate them.

"I will tell you that this has been a constant frustration for every municipal politician in this country forever."

The mayor said the bridge in question is old and was not built into the bedrock — "something I didn't know until today" — whereas all the city's bridges are. He said all the municipal bridges had been inspected three times since the flood and were solid.

Emergency crews were undertaking a delicate operation to secure the derailed cars and empty them before they fell into the water.