(Bloomberg) -- Despite threats of U.S. auto tariffs and heated trade talks, it’s full steam ahead for Canada on a new bridge between the two countries.

The contract to build and operate the Gordie Howe International Bridge connecting Detroit and Windsor was finalized Friday with an estimated lifetime cost of C$5.7 billion ($4.4 billion). The consortium includes Toronto-based Aecon Group Inc. and the Canadian units of Madrid-based Actividades de Construccion y Servicios SA and Texas-based Fluor Corp.

It would bring a new 1.6-mile, six-lane bridge across the Detroit River -- the busiest corridor in Canada-U.S. trade, particularly for the auto sector. The bridge is being financed by the Canadian government and isn’t scheduled to open until 2024, but is nonetheless a bet that trade tensions will pass.

“There will always be a trading relationship between Canada and the United States,” said Dwight Duncan, board chair of the Windsor-Detroit Bridge Authority and former Ontario finance minister. He said they “never” considered delaying the project, pending trade talks. “Whatever glitches happen in the next six hours, six days, six months, there will continue to be a need for this crossing, there will continue to be trade.”

The bridge project is exposed to several fronts of the trade fight between the U.S. and Canada. The American owners of an existing, rival bridge are pressuring President Donald Trump -- who is currently frustrated with Canada -- to revoke a key waiver for the new one. Trump has threatened tariffs on Canadian auto imports, which would upend traffic and toll levels. A potential collapse of the North American Free Trade Agreement could sap trade between the nations.

Despite that, the bridge has support from a wide range of U.S. and Canadian political leaders of various partisan affiliations.

Duncan declined to say whether he has assurances the Trump administration won’t intervene, saying the president praised the project in a joint statement with Canadian Prime Minister Justin Trudeau last year.

“My job’s to get the bridge built and the bridge is going to get built,” Duncan said. “This is an important reminder of our commitment to the ongoing relationship between our two great countries.”

The bridge will be built with North American steel, primarily sourced within Canada. Tariffs on steel applied by both the U.S. and Canada are “not a big issue” for the project, Duncan said.

Tolls, Traffic

The public-private partnership contract includes C$3.8 billion to build the project and C$1.9 billion to operate it for 30 years. The price is higher than initially estimated, but Duncan said the previous Canadian government “grossly” underestimated the cost and timeline for the large-scale project.

The owners of the existing Ambassador Bridge said traffic levels have been falling -- raising the prospect of a bridge growing in cost and hoping for a split share of declining toll revenue to pay itself off. Duncan brushed that aside, saying “it’ll be all recouped” and that traffic levels are falling in part “because of the poor condition of the other border crossings.” He didn’t say which. Traffic historically “trends up and it will continue to trend up, particularly on the commercial side,” he said.

The builder consortium raised C$446.4 million in bond sales last week. S&P Global Ratings assigned the project a preliminary A- rating last month, which it said “reflects the strength and experience of the highly integrated consortium.” The project will create 2,500 construction jobs, the Windsor-Detroit Bridge Authority said in a statement.

To contact the reporter on this story: Josh Wingrove in Ottawa at jwingrove4@bloomberg.net

To contact the editors responsible for this story: Theophilos Argitis at targitis@bloomberg.net, Stephen Wicary

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