TransLink will scale back a proposed $100-million rehabilitation of the aged Pattullo Bridge, saying the projected cost of bringing the crossing up to seismic standards is becoming “prohibitively expensive.”

Fred Cummings, TransLink’s vice-president of engineering and infrastructure management, said it would likely cost another $20 million for the proposed upgrade and TransLink would instead focus on the doing the minimum needed on the bridge deck to extend the life of the crossing until a replacement is built.

Cummings warned TransLink directors on Friday that a new bridge can’t come soon enough, noting the agency can’t keep plowing money into the 78-year-old link between Surrey and New Westminster.

“It’s very critical,” he said. “A lot of money has been put into this bridge to keep it limping along. If we don’t come up with money to replace it, we won’t have a crossing to depend on.”

TransLink had planned major closures on the Pattullo Bridge, starting in mid-2016 and running for 18 months, as part of its $100-million rehabilitation project, which was expected to focus on seismically upgrading and repairing the bridge deck, whether by milling and replacing the concrete on some sections or bringing in pre-cast sections.

The work follows a succession of temporary closures in the past decade for repeated patch jobs on the bridge deck to keep it maintained until a new crossing is built.

But Cummings said new information suggests there would also need to be massive work to the bridge’s bearings, approaches and structural foundation, which includes timber piles, to make it structurally sound.

He wouldn’t say when the Pattullo Bridge would be unsafe to use, but guessed it would be “10 years on the outside.”

“We can’t find a technical solution to maintaining the life of the bridge,” he said. “We’re making recommendations to the board that we focus on the truss sections of the bridge itself to reduce the scope and the cost.”

The decision to reduce the project was heralded as good news by mayors of Surrey and New Westminster, who were concerned about traffic disruptions on the bridge, which was slated to be closed to all traffic during nights and weekends if the upgrade went ahead.

The scaled-back project, expected to cost just $25 million, will only take five months and keep two lanes on the four-lane bridge open at all times. About 75,000 vehicles use the Pattullo daily, mainly because many drivers don’t want to pay the $3 toll on the new Port Mann Bridge.

“I never did like the idea of spending $100 million on a bridge that was too old and needed to be replaced,” Surrey Mayor Linda Hepner said.

New Westminster Mayor Jonathan Cote agreed, saying the money is better spent designing a new bridge, which he hopes can be finalized next year. A new $980-million, four-lane crossing, with the potential to expand it to six lanes, has long been a priority in TransLink’s 10-year plan but the transportation agency must come up with its share of the funding, which is to be split three ways with the provincial and federal governments.

Cummings estimated that if TransLink had the money today, it could design and build a new bridge in five years.