Two Metro Vancouver mayors fear safety and congestion issues could arise on the Pattullo Bridge after tolling begins on the Port Mann Bridge at the end of the year.

The 75-year-old Pattullo Bridge connecting Surrey and New Westminster is well known for its age, dangerously narrow lanes and deadly crashes. Surrey's Mayor Dianne Watts and New Westminster's Mayor Wayne Wright are concerned the bridge's problems could be exacerbated when it becomes the free alternative to the tolled Port Mann Bridge.

Watts says the infrastructure doesn't exist for the extra volume.

"The diversion of traffic is significant for us. We've got the expansion at Deltaport, there's the Surrey Fraser Docks down there, we've got the second-largest border crossing in the country," she said. "The Pattullo Bridge does not have the capacity to carry on the traffic for two bridges."

Wright shares these concerns, and adds safety is a serious consideration when it comes to increased traffic on the aging bridge.

"What's going to happen with the bridge when they get cars and trucks pounding on it more than there is now?" he asked.

The Ministry of Transportation says it has to provide a free alternative to the Port Mann Bridge, and that the Pattullo Bridge is the best option. While the ministry is expecting more traffic on the latter, it says once people realize how much faster the Port Mann Bridge is, they will travel on it and pay the $3 one-way fee.

Watts isn't convinced this will be the case.

"If we look at, historically, what has occurred with the Golden Ears Bridge, people aren't using it because the tolls are too high," she said.

Both mayors are rehashing the idea of tolling all bridges to even out demand while financing future projects, although provincial policy allows the tolling of only major new projects.

"I think most of the mayors on either side of the river are of the same mind. We all want a transportation system that works for everybody. Nobody wants to pay more than anybody else," Wright said.

TransLink wants to replace the Pattullo Bridge by 2018, which would eliminate it as a free alternative.

With a report from CTV British Columbia's Penny Daflos