What's next for a new I-5 bridge between Washington and Oregon

A new Interstate 5 bridge over the Columbia River is expected to begin construction in 2026, after the project recently snagged a $600 million federal transportation grant .

Why it matters: The current I-5 bridge connecting Oregon and Washington carries more than 130,000 vehicles a day . But it isn't built to modern standards and could collapse in an earthquake.

Friction point: The bridge also causes major traffic backups when its moveable span rises to let boats pass beneath.

• Project officials say the river crossing between Portland and Vancouver is the only part of I-5 from Canada to Mexico where vehicles must stop at a red light.

The big picture: The recent $600 million grant from the U.S. Department of Transportation is enough to cover about 8–12% of the project's estimated cost of $5 billion to $7.5 billion.

Yes, but: Combined with other money already identified, the project is somewhere between half and two-thirds of the way toward being fully funded.

• Washington and Oregon have each committed about $1 billion, while another $1.2 billion is expected to come from tolling revenue, per a presentation made to the bridge project's executive steering group on Tuesday.

Caveat: A new cost estimate for the bridge is expected this summer, which may change the overall price tag.

• Project officials are seeking up to $2.5 billion in additional federal money to cover the remaining gap.

What they're saying: "The $600 million federal grant is a crucial step towards starting construction in 2026 because it sets us up for additional funding from the federal package in the next few months," Oregon state Rep. Susan McLain (D-Hillsboro), who co-chairs the Legislature's Joint Transportation Committee, said in a written statement.

Catch up quick: The new bridge is expected to have wider vehicle lanes, a light rail line and a new path for pedestrians and bicyclists.

• Beyond that, however, its design is in flux as the project undergoes a lengthy environmental review process.
• "This is going to be a bigger bridge than currently exists — we know that," bridge program administrator Greg Johnson said at Tuesday's steering group meeting. "It's going to carry more types of transportation."

Zoom in: Project officials are still comparing three different configurations.

• Two options, a double-level bridge or a wider single-level bridge, wouldn't rise to let boats through, avoiding the problem of freeway traffic backups.
• Either option is expected to be much taller than the current bridge, providing an estimated 116 feet of vertical clearance for boat passage, compared to 72 feet under today's bridge when it's not raised.
• A third option would include a moveable span allowing boats up to 178 feet tall to pass through. The U.S. Coast Guard has pushed for this, and the current bridge accommodates it when it's lifted.

What's next: The bridge program plans to release a draft environmental impact statement sometime this spring, which will kick off a 60-day public comment period.

• After that, Johnson said, his team would recommend one of the three bridge configurations, with a final decision expected late this year or early in 2025.

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