Municipal leaders and rail advocates offered ideas Wednesday night for extending passenger train service south to New York City and north to Augusta, Auburn, Bangor and Montreal.

But the existing Downeaster service between Brunswick and Boston must be improved before any expansion will be possible, said Patricia Quinn, executive director of the Northern New England Passenger Rail Authority, which runs the service.

“It is a trunk of a tree,” she said of the Brunswick-Boston route. “If we have a strong tree, that supports limbs and branches.”

The issue was raised during a public hearing on the 20-year plan for Amtrak’s rail service. The planning study, funded largely from a $600,000 grant from the Federal Rail Administration, is required by the agency to justify requests for capital funding for service improvements.

Although it received the funding in 2011, the rail authority held off on the study until service was established between Portland and Brunswick. That service began in late 2012. The study is expected to be completed in June.

At Wednesday’s hearing at Portland City Hall, attended by about two dozen people, a range of ideas were raised for improving or extending passenger train service in Maine.

At times, advocates for extending service to Auburn and Lewiston appeared to be competing with those who want to bring the service to Augusta.

Auburn Mayor Jonathan LaBonte noted that the Lewiston-Auburn area is the second-most densely populated area in Maine, and that half of the households in downtown Lewiston don’t have cars.

“They would love the chance to have mobility,” he said.

Richard Rudolph, representing the Maine Rail Group, advocated for extending passenger service to the east side of Augusta, noting that it would be a relatively short trip from Brunswick on an abandoned rail line the state already owns.

“It is our belief that this is the next logical step,” he said.

TrainRiders/Northeast, the citizens group that led the petition drive nearly 25 years ago that led to the start of the Downeaster service, has long advocated for extending the service north. It is now also lobbying to extend passenger service to New York City through Worcester, Mass., instead of Boston.

The rail authority’s board of directors voted in January to study the idea, which is also popular in Worcester. Quinn said the route is worth pursuing because the biggest draw for the service now is Boston, which is the departure point or destination point for 86 percent of all Downeaster passengers.

“Connecting to a large population is important,” she said.

But before the service is extended, Quinn said, it is critical to improve the speed and frequency of the existing service.

Rather than increase the trains’ top speed of 79 mph, she said, the trip could be shortened by improving sections of track where the speed limit is now 60 mph.

It now takes two hours and 30 minutes for a Downeaster train to travel between Boston and Portland, while stopping at eight stations along the way. A bus or car can usually make the trip in less than two hours.

The rail authority could add a daily run between Portland and Boston with its current train equipment, Quinn said.

The service now offers five round trips daily between Portland and Boston, leaving long gaps between trains that make the service inconvenient for many people, she said.

Quinn said the authority is looking at the possibility of adding a trip without having to acquire additional equipment.

While the train station in Portland is favorably situated near Interstate 295 and the Concord Coach Lines station, Quinn said, it is removed from Portland’s downtown, creating a barrier for tourists and residents. She said improved public transportation is needed between the station and downtown.

Tom Bell can be contacted at 791-6369 or at:

tbell@pressherald.com