Construction projects are weakening the Champlain Bridge in Montreal, prompting a ban on trucks carrying heavy loads.

Starting Monday, the St. Lawrence River bridge connecting Montreal to boroughs on the South Shore, was deemed off limits to any trucks hauling more than 66 tonnes.

“For us, targeting those excess loads ensures that we can keep that safe transit for commuters that use the bridge … every day, and for those trucks that carry the economic vitality of Montreal,” said Julie Paquet, a spokesperson for the Champlain and Jacques-Cartier bridges.

The concern is the volume of trucks that are carrying bulldozers, steel beams and concrete structures to the city’s major construction sites.

Marc Cadieux, president of the Quebec Trucking Association, said the ban has the trucking industry concerned over the higher cost of transporting goods.

“It certainly will impact on cost of carrying those merchandise, those pieces of equipment and those structures that need to be crossed through Champlain Bridge they will have to go by alternative ways,” Cadieux told CTV Montreal.

Those with the heaviest loads will require a special travel permit from the Societe de l’assurance automobile du Quebec to travel over the Champlain Bridge.

It’s estimated 2,000 heavy trucks rely on crossing the Champlain Bridge, so banning them will be expensive.

Cadieux says the problem is that options are limited for the heaviest loads. The Jacques Cartier Bridge is off-limits, as is the Mercier Bridge southbound, leaving few options: barges across the river or the Lafontaine Bridge-Tunnel, which is several kilometres out of the way.

That means for delays for truck drivers, who say they are losing at least one hour a day getting into Montreal.

“Everywhere there’s traffic,” says truck driver Alex Simionov.

The ban, which is in effect until a new bridge opens at the end of 2018, is inconvenient but necessary as the infrastructure nears the end of its lifespan.

Until then, the bridge corporation is expecting to spend $100 million per year to keep the existing one standing.

With files from CTV Montreal’s Annie DeMelt