A proposed 12-mile light rail extension to the Bridgeport Village mall now faces a $400 million funding gap, TriMet officials said this week, after planners cleaved tens of millions in potential spending in an attempt to address the financial issue.

But even cutting an estimated $62 million from the preliminary budget leaves tough decisions before the elected officials and transportation leaders who sit on TriMet’s steering committee tasked with overseeing the massive project.

If the light rail project extends all the way to Bridgeport Village, a key issue for Washington County’s commission and Tualatin officials, just eliminating some aspects of the project won’t be enough to fill the yawning budget hole. The region will still need to ask for more money.

According to multiple scenarios presented to a community advisory group, the project may need to find another $200 million in cash.

TriMet has said it doesn’t believe it could receive more than $1.25 billion from the federal government. Some $850 million is expected to be included on the 2020 Metro transportation package.

Roberta Altstadt, a TriMet spokeswoman, said where the $200 million may come from “remains to be seen.”

“Other project partners are well aware of the current cost estimate and gap in funding identified thus far,” she said in an email. “More discussions will be had with jurisdictions and partners.”

As of last month, the light rail project was projected to cost $2.87 billion to build by the time it opened in 2027. The agency now says it could cut about $62 million from the total price tag by reducing the amount of stormwater infrastructure through the area, buying up fewer properties to widen the road in some spots and creating fewer special sections of track called “crossovers” where trains can switch from one set of tracks to the other.

“Partners are working together to explore potential cost reduction strategies and keep the project on schedule,” TriMet officials wrote in a document posted to the light rail project’s website this week. “The magnitude of the cost gap means the team must find significant ways to reduce the amount of infrastructure the project will build, and potentially increase funding.”

The project is more than just light rail. It includes miles of bike lanes, pedestrian crossings and sidewalks in and along Barbur Boulevard in the hilly Southwest Portland neighborhoods and beyond. Planners are banking on receiving a combined $2.525 billion from the federal government, a 2020 Metro transportation funding package and local governments like the city of Portland.

Bringing the train all the way to Bridgeport Village remains the top option, but it’s also the costliest.

According to draft plans presented to a community advisory group Thursday night, TriMet estimates it could save $200 million on Barbur by doing the following:

-Diverting the trains to run along Interstate 5 in some areas, instead of down the middle of Barbur.

-Reducing Barbur to one travel lane in either direction between Barbur Transit Center and Southwest 30th Avenue, between Southwest 30th Avenue and 19th Avenue and between Southwest Capitol Highway and Brier Place.

Tigard’s mayor last month said it was critical to retain two travel lanes on Barbur, even on areas that are within the city of Portland. Washington County officials had said they would not pay their share of the project, $75 million, if the light rail line doesn’t go all the way to Bridgeport Village.

TriMet also presented three additional options to cut costs.

The transit agency could build a light rail line that ends at the Bonita or Upper Boones Ferry station and save $200 million. Couple that option with reducing travel lanes on Barbur and routing the train along I-5 would eliminate the need to raise another $200 million from local sources.

Another option – ending the route at Bonita or Upper Boones Ferry while maintaining all current travel lanes on Barbur – would leave a $200 million funding gap.

The third option, ending the route at Southwest Hall Boulevard, would save the full $400 million. That option would mean the light rail line would open with 10 stations instead of 13. Plans indicate the project could be “phased in” down the line.

The agency plans to present a more thorough traffic analysis of what the lane changes would mean on Barbur at the upcoming Steering Committee meeting Sept. 23.

-- Andrew Theen

atheen@oregonian.com

503-294-4026

@andrewtheen

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