TRENTON – A multimillion-dollar Acadia National Park transit and visitor center proposed for a 369-acre parcel off Route 3 generated heated questions Wednesday night from some residents concerned that their traffic woes will increase, but their tax base will fall.

The center is designed to serve as a hub for the nearby park’s popular fleet of propane-powered Island Explorer buses, and it could attract day-trippers as well as Mount Desert Island workers who live elsewhere.

Planners hope the center will reduce traffic congestion on MDI, improve air quality and help share park and regional information with tourists before they cross the bridge to the island.

More than 70 people gathered Wednesday night at the elementary school to participate in the first public discussion of the proposed center.

“Transportation is not an issue specific to the town of Trenton,” said Selectman Jim Cameron. “It’s a regional issue. … And whether we like Acadia National Park or not, we need to agree that without Acadia National Park this wouldn’t be the region it is today.”

Some apparently frustrated residents suggested that officials from the park and the state Department of Transportation, among the project’s partner organizations, have made all the decisions about the proposed center and that what the townspeople want doesn’t matter.

“I’m going to suggest that this was a done deal,” said resident Michelle Woodbury. “We are just wasting our time by being here.”

Another resident, Ward Holder, said he didn’t appreciate how the project planners handled the presentation.

“All of your language tonight is that you’re here to tell us what you’re going to do,” he said as the crowd applauded. “I’m not happy.”

But such allegations and concerns, Cameron said, are unfounded.

“We are not trying to hide anything,” he said. “It is not a done deal … [Trenton] is going to maintain a very, very active presence in this process all along.”

Many in the crowd questioned the decision to locate the transit center in Trenton rather than on MDI, in Ellsworth or even in Bangor.

Officials responded by saying that years of studies and user surveys have showed that the so-called Crippens Creek parcel, a 369-acre swath of land just two miles north of the Hancock County-Bar Harbor Airport, is the right location.

“Our study … really pointed towards Trenton as the right place to build an intermodal facility,” said Ron Roy, director of DOT’s passenger transportation office. “For the bus system it allows more flexibility, and if our objective is to take day-trippers off the road, it’s very important to get them before they hit the bridge” connecting Trenton and MDI.

Officials stressed that they are at the beginning stages of planning and that they want to hear what Trenton residents would like to get out of the facility.

Traffic concerns were shared by some from the neighboring city of Ellsworth, which is working on streamlining Route 3 traffic through its congested business district.

“Everybody that comes through Trenton comes through Ellsworth,” Ellsworth City Councilor Gary Fortier said. “I worry that the increase of traffic coming through Ellsworth is going to erode the capacity that we are paying to put in.”

Fortier wanted to know if there might be money available for “upstream development” in Ellsworth.

While he had no immediate answers to that, Roy said that this is the right point for raising such specific concerns.

Roy said he believes the Trenton hub would be one the region can be proud of.

“Whatever gets built, if anything gets built, it’s going to be nice,” he said. “It’s not going to be a green DOT building … it’s not going to be a humongous parking lot. It’s going to be something that works for you. That’s why we need your input.”

Trenton resident Bob Gates said that it would be short-sighted for townspeople to take a “Not in My Backyard” approach.

“I can see several ways this project could be helpful to Trenton,” he said. “It could benefit us not just as parochial folks in Trenton, but as folks who live in the world.”

Questions or comments about the intermodal transit facility should be addressed to Tracy Perez of the Maine Department of Transportation at 624-3248 or by e-mail at tracy.perez@maine.gov.