BAR HARBOR – The Island Explorer bus service plans modest, new services this summer while awaiting word on whether the federal and state governments will fund eight new buses for the burgeoning transportation system.

If approved, the new buses would allow year-round service not only on Mount Desert Island, but also from MDI to Ellsworth, Bangor and as far east as Milbridge and Cherryfield, according to Island Explorer planner Tom Crikelair.

The buses would carry MDI workers to jobs in Ellsworth and Bangor and bring workers from those areas to the island to work for The Jackson Laboratory and other island businesses.

“We’ve got a program that’s really working,” he said. “We’re carrying way more people than we ever thought we would.”

For now, the summer bus service will offer an extra morning run from Southwest Harbor to Bar Harbor, arriving at 7:20 a.m. and 8:20 a.m. Also, the half-hour runs from Acadia National Park campgrounds will be extended daily to 7 p.m., rather than 6 p.m.

After 7 p.m., the buses will run every hour.

The Island Explorer, owned by Downeast Transportation, also is considering leasing extra buses for the peak summer traffic from the last week of July through mid-August, Crikelair said.

“The bigger changes are ahead,” Crikelair said.

If the service gets the eight new – and bigger – buses through federal and state transportation programs, it would put four of them on the campground routes, which have some of the heaviest ridership; add another bus to the Southwest Harbor route; and free up the smaller buses to increase the frequency of runs on the Sand Beach, Jordan Pond, Blackwoods and Brown Mountain routes, he said.

The 17 buses now in service seat 28 people each. The new buses would accommodate 38 each.

Crikelair said the proposed operational budget for the new year is just over $570,000, of which $306,000 is covered by Acadia and another $150,000 comes from federal transportation money in an ongoing annual grant.

This year’s grant was announced this week by members of Maine’s congressional delegation.

The island communities pay about 10 percent of the cost, or $59,000, with Bar Harbor paying the most at $30,000.

“I think definitely there is a lot of interest in town for expanding the Island Explorer service,” Bar Harbor Town Manager Dana Reed said. “For what the town pays for that service, I think $30,000 is a really good bargain.”

The bus service also recognizes that patrons, businesses and communities supporting the service want the runs extended from Labor Day to Columbus Day and eventually to provide year-round service, Crikelair said.

“When the service needs to expand, we have to get the federal and state governments to cover the cost,” Crikelair said. “Except for cost of living adjustments, we really do not intend to come back to the [communities] and ask for big increases.”

The Island Explorer gets little criticism, except that some people think it should charge riders a fee. Crikelair said he and others think a fee system would only discourage use, which would be counterproductive to the goal of the service.

Crikelair noted that riders who take the buses to Acadia pay an entrance fee there, and a portion of that money is used to finance the service.

Also, the Explorer gets about $10,000 a season in voluntary fares from riders. And businesses that get front-door service chip in a total of $31,380 for the bus service.

The bus service began in 1999 with projections of 1,000 riders a day. One day last summer, at the peak of the tourism season, 5,004 people rode the buses.

The average daily ridership, after just three summers, is 4,000 to 5,000, a 75 percent increase from the inaugural season. Crikelair said if there were more buses, there would be more riders still.

Paul Haertel, Acadia superintendent, said park officials are gratified that the buses are filled to capacity, something that helps eliminate traffic, improve air quality and protect wildlife and natural resources in the park.

Haertel said he also expects an expansion of service in the future. He said he’s optimistic that the federal transportation department would fund four new buses, “but I still want to wait for that piece of paper.”

Haertel said the park will track visitors better than ever this summer with new technology provided under a federal pilot program. Although the park is rated No. 2 in the nation for visits, at about 3 million a year, Haertel said that figure includes multiple visits by the same people.

The park cannot say for sure how many cars enter the park annually. The new traffic counters should be able to provide a more accurate accounting.