A long-discussed plan to bring more transit service to Southwest Portland and job centers in Tigard and Bridgeport Village moved another step closer to reality Thursday.

The Metro council unanimously approved the preferred route for an estimated $2.6 billion to $2.9 billion light-rail line project, which would extend the transit service 12 miles through an underserved and growing part of the Portland region.

The council’s vote comes on the heels of similar approvals from Portland, Tigard, Tualatin and Washington County elected officials in recent weeks, and it marks the final approval needed from a local government before planners can begin refining the design and conduct a final environmental impact statement.

A final environmental impact statement is expected in late 2019, and Metro will likely include the light-rail expansion on a planned 2020 transportation bond package. The project is contingent not only on local funding, but also on an eventual 50 percent funding share from the federal government. If everything goes according to plan, the project could be under consideration for federal funds in 2023, and the first trains could roll in 2027.

A map of the proposed 12 mile light rail line from Portland to Bridgeport Village.

Metro planners have estimated the 12-mile route, which would end at Bridgeport Village, would draw up to 43,000 riders by 2035. The so-called Southwest Corridor, which largely centers around Barbur Boulevard, would include 13 stations and seven park and ride stations.

The multibillion-dollar price tag includes miles of new sidewalks, protected bike lanes and other safety improvements throughout the 12-mile corridor. It doesn’t include several critical infrastructure projects along the route, such as reconfiguring the Ross Island Bridge’s on- and off-ramps on the west side, a projected $80 million to $150 million project which would transform the surrounding neighborhood.

Projects to replace two aging viaducts at Newbury and Vermont streets are also critical to the light-rail plan. Oregon Department of Transportation officials did not immediately provide cost estimates to replace those bridges.

-- Andrew Theen

atheen@oregonian.com

503-294-4026

@andrewtheen