Bridge lane closures cause major commuter headaches

The sudden closure of the southbound lanes on the Mercier Bridge has had a domino effect on the island of Montreal, slowing up traffic on all the links to the south shore.

Civil engineering Professor Emeritus Saeed Mizra explains the structural problems on the bridge and why gusset plates are so key. He points out that plate failure led to the collapse of a bridge in Minnesota four years ago.