The B.C. NDP has announced it's moving forward with construction of a $1.37-billion replacement for the aging Pattullo Bridge.

Speaking at a news conference in New Westminster Friday, Premier John Horgan revealed the pricey project is going to be delivered solely by the provincial government, with construction expected to begin in summer 2019.

"This bridge was designed in the 1920s, built in the 1930 and is well past its best before date," Horgan told reporters. "It's been a long time coming, but after 80 years of service the Pattullo Bridge has done its bit for British Columbia, and it's time for a new bridge."

The funding, which was previously planned to be split with TransLink, will come from the province's three-year, $14.6-billion capital plan.

Taking over the project will ease the financial pressure on TransLink and its Mayors' Council, which have a number of other expensive transportation promises in their 10-year investment plan, including light rail in Surrey and the Broadway SkyTrain expansion.

It will be built with four lanes but designed to fit two additional lanes if needed.

"It's our view and the view of TransLink and the officials at the Ministry of Transportation that four lanes with an ability to go to six is appropriate," Horgan said.

Concrete on the Pattullo, which is decades past the 50-year lifespan it was designed for, began to crumble years ago, and the crossing was partially closed for months in 2016 to undergo crucial repairs.

Transportation Minister Claire Trevena said the bridge is riddled with safety issues, including lanes that are uncomfortably tight when driving side-by-side with big shipping vehicles.

"It is critical for the region and for the province, it is part of our trade network, but it is dangerously old," Trevena said. "It was not designed for the size of vehicles we have now, it was designed for the size of vehicles we had in the 1920s."

Despite those concerns, the Pattullo still sees around 68,000 crossings a day.

The replacement will be built to modern safety standards, with a centre barrier and wider lanes. It will also have separated walking and cycling lanes on both sides.

It is expected to open to traffic in 2023.