AUBURN — Passenger rail advocates made a pitch Thursday to reuse the former Grand Trunk Railway between Portland and Auburn for a new, battery-powered passenger service.

In a presentation to the Portland to Auburn Rail Use Advisory Council, convened by the Maine Department of Transportation, the rail advocates said they envision the “Grand Trunk Flyer” making daily roundtrips, eventually extending to the Ocean Gateway terminal in Portland.

The dormant route follows the St. Lawrence and Atlantic line, which has also been the subject of a popular proposal to create a multiuse “rail trail” along the line.

Proponents of that plan have said the rail trail would not interfere with efforts to add passenger rail between Portland and Lewiston-Auburn because a rail service could use the parallel Pan Am Rail Line, which would take passengers to the Portland Transportation Center near Thompson’s Point.

However, those behind the “Grand Trunk Flyer” proposal argued Thursday that the St. Lawrence and Atlantic line is an “irreplaceable asset” that could be used for interurban light rail at a cost far lower than previous studies have estimated.

Tony Donovan, a Portland realtor and director of the Maine Rail Transit Coalition, said there’s a perception that railroad tracks, owned by Maine citizens, “cannot be used for trains.”

He said the team behind the “flyer” proposal has determined that light rail could operate on the track close to its current condition.

Al Fazio, an engineer with BRT Services and former deputy chief engineer for Amtrak, said a 2019 report that looked at passenger rail between the regions had several errors. He said many places across the country have seen redevelopment around light rail corridors that can provide zero-carbon transportation, “getting people to work even if they can’t afford a car.”

BRT is a professional firm in Havertown, Pennsylvania, specializing in support to railways with high volume services, according to its website.

According to a news release on the proposal, reaching downtown Portland would require rebuilding the trestle traveling across from the former B&M Baked Beans property to the east end of Portland. They envision stations at the incoming Roux Institute, as well as in Falmouth, downtown Yarmouth, Yarmouth Junction, the Pineland Farms campus in New Gloucester, and the Auburn-Lewiston Municipal Airport in Auburn.

The release said the Maine Rail Transit Coalition is preparing for a demonstration of the new train, which would operate between Presumpscot Street and Yarmouth, as early as next year.

Donovan and Fazio said “people need to see it and touch it,” and the demonstration could show people that the technology can work on the line.

“This railroad, and all state railroads, are available right now to provide equitable access to housing, jobs, and services,” Donovan said. “It must be used to address the immediate crisis we have in climate change.”

Asked who might eventually operate the service, Fazio said it would likely not be Amtrak, but that there could be a “cross-platform” connection at the Yarmouth Junction to the Amtrak service that runs between Brunswick and Boston.

In 2021, Lewiston partnered with Portland to fund a study looking at passenger rail between the regions.