Friday marks ten years since the de la Concorde overpass in Laval collapsed, killing five and injuring six more.

On September 30, 2006, the de la Concorde Bridge over Highway 19 fell. The 40-year-old structure was later destroyed and rebuilt, as was another nearby overpass that suffered from the same structural problems.

An inquiry learned that signs of the collapse had been spotted an hour before the viaduct came down.

At 11:25 a.m., the Surete du Quebec learned that a piece of concrete fell from the de la Concorde overpass.

Traffic reporters were advised at 11:35 a.m., the transport department made a visual inspection just before noon and police reported a second fallen chunk at 12:33 p.m.

No one mentioned anything to drivers.

At 12:37 p.m., a 20-metre section of the structure collapsed onto the highway below, crushing several vehicles down to the level of rescuers' ankles.

Jean Charest was Quebec’s premier at the time, and appointed one of his predecessors, Pierre Marc Johnson, to head up a public inquiry into the disaster.

Johnson dropped a bombshell even before he tabled his report, when he announced in the summer of 2007 that 135 bridges and overpasses needed to be demolished or urgently repaired.

His final report in October 2007 found that the de la Concorde overpass was poorly designed, with concrete that couldn't withstand freeze-thaw cycles or road salt.