The new, "super-sized" Port Mann Bridge will be finished in 2012 -- a year ahead of schedule, according to provincial Liberal leader Gordon Campbell.

Campbell made the announcement during a tour of the construction sites of the Port Mann and the Pitt River Bridges during day four of the B.C. election campaign.

"We're building this new, 10-lane bridge to improve travel on one of the Lower Mainland's busiest transportation corridors, cut travel times for thousands of commuters every day, bring transit back for the first time in two decades, and reduce the congestion costs our economy $1.5 billion each year."

The Pitt River Bridge connecting Pitt Meadows and Coquitlam will also be open early, with construction finishing several months ahead of schedule.

Campbell says demand for the expanded Port Mann, which connects Surrey to Coquitlam, is bigger than ever.

"People living south of the Fraser want to see this bridge built; Lower Mainland commuters want to see this bridge built; B.C. businesses want to see this bridge built; and the BC Liberals are building this bridge," he said.

In February, the B.C. government was forced to take over the entire $2.4-billion cost of the Port Mann Bridge project after plans for a partnership with a private consortium fell through.

Drivers will pay a $3 toll each way to use the new bridge. The cost of the tolls will rise depending on inflation and could be in place for up to 40 years.

The new bridge replaces the 45-year-old structure, and will include $50 million in cycling infrastructure.

The Port Mann bridge project also includes widening the Trans-Canada Highway from Vancouver to Langley and upgrading interchanges along the route.