A Montreal truck driver was killed Thursday morning when his tractor-trailer veered off Highway 40 and plunged into Lake of Two Mountains.

According to SQ Sgt. Joyce Kemp, police are examining the theory that 48-year-old Sylvain Brunet fell asleep at the wheel.

"We don't know yet what caused the loss of control," said Kemp.

Witnesses told police the truck started drifting to the right at it approached the Ile-aux-Tourtes bridge in Vaudreuil-Dorion at 5:20 in the morning

The truck crashed through the guardrail at the start of the bridge and then careened down the embankment into the lake.

The trailer was torn loose, while the cab smashed into a concrete support at the base of the bridge then burst into flames.

Police closed the bridge, and it took nearly three hours for S�ret� du Qu�bec officers to find the driver.

Traffic was closed in both directions on the bridge, with westbound lanes re-opening at 6:30 a.m., and two eastbound lanes opening shortly after.

However the damage was done, and the closures left traffic snarled for much of the day.

Complicated removal

Hauling away the wreckage from the truck crash is complicated because the ground by the lake is so soft.

Glen Comeau of West Island Towing is one of the people building a temporary gravel road to support the weight of heavy equipment.

"We will slide the trailer up onto dry ground, unload the load into containers, up-right the trailer and get both units out ," said Comeau.

Trucking regulations

Given the theory that Brunet fell asleep while driving, Quebec Trucking Association president Marc Cadieux says driver hours are closely monitored to make sure they stay alert behind the wheel.

"There's no reason in today's ways of working that you should push your driver more than the allowed hours by law," said Cadieux.

Truck drivers are allowed to work for a maximum of 13 hours a day, with a mandatory two hours in breaks.

They must have eight hours between shifts, and trucks that operate in Quebec are now restricted to 105 km/h.

"It seems to have helped with the trucks being regulated with speed," said Cadieux. "We've noticed in our industry that it's... these accidents are down a little bit."

Police are also investigating whether the driver may have had a medical emergency or whether mechanical trouble could have contributed to the crash.

Brunet worked for Alexcalibur Transport of Dorval