PORTLAND, Ore. - The plan to tackle traffic across the Columbia River between Portland and Vancouver, Wash., is expected to move one step forward Monday night as the Vancouver City Council casts a vote on the design it prefers.

Current plans call for replacing the six-lane Interstate 5 bridge with a 12-lane toll bridge, light-rail extension to Vancouver and bicycle and pedestrian improvements.

Vancouver officials are the first of eight local, state and federal entities to weigh in on the Columbia River Crossing project. The project's sponsors are trying to get all of them to agree on a locally preferred alternative by August.

The Portland City Council along with transit agencies for both Portland and Vancouver are expected to also vote on the project this week.

The news comes as The Oregonian reported Monday that a new study shows that even if the $4.2 billion project is completed, traffic could be back to the same levels by 2030.

And the new bridge does nothing to relieve the bottleneck at the Rose Quarter as southbound drivers approach downtown Portland.

Supporters of the bridge agree that it's not a perfect solution. But they say doing nothing will result in even more congestion.

- The Associated Press contributed to this report