Passengers board the Island Explorer next to the Village Green in 2014.

BAR HARBOR, Maine — Mount Desert Island’s fare-free bus service says its 2018 season is off to a good start.

From the beginning of their season, June 23 to July 3, Island Explorer buses have carried 66,276 passengers around the island, including cruise ship tourists visiting Acadia National Park. That number is about 4 percent, or 2,418 passengers, above the 63,858 passengers carried between those dates last year, said Paul Murphy, the service’s executive director.

The increase comes at an interesting time for Bar Harbor. Pressed by residents to relieve traffic congestion, town officials plan to turn a former ferry terminal into a multiuse marina that officials hope will eventually be used to better manage traffic, while Acadia National Park leaders are working on a plan to improve the park’s traffic flow.

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The bus service’s passenger increase is likely attributable to good weather, continued expansion of the cruise ship industry and a good economy, but it’s unclear whether the trend will sustain itself the end of Island Explorer’s season on Columbus Day, Murphy said.

“We could get two weeks of rain that could bring us right down again,” Murphy said. “If it [the increase] holds, it mirrors a trend we have seen for the last several years that more people are coming to Acadia and coming to Maine.”

Island Explorer carried 581,305 riders in 2017, which was 1 percent above 2016, 9 percent higher than 2015 and 16 percent higher than 2014. The summer average in 2017 was 6,591 riders per day. The one-day peak in 2017 was Aug. 9, with 9,887 riders, according to the service’s website.

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Island Explorer’s propane-powered fleet of 30 buses is funded by public and private entities, including Acadia, several Hancock County towns and L.L. Bean, which has given the service $1 million grants annually for the past five years.

Acadia funds about 60 percent of the service’s $2.3 million budget, Murphy said.

Jeff Small, the service’s Bar Harbor supervisor, said that this year’s increase in traffic was noticeable. On June 26, a cruise ship deposited about 3,000 people in Bar Harbor.

“It’s unusual to have a ship with that many people here this early in the season,” Small said. “The peak of the season is usually the second week of August.”

The bus system was established in 1999 and is estimated to have carried a total of more than 6 million passengers over the past 17 years. Officials with Downeast Transportation, which operates the service, and Friends of Acadia say the system gets about half a million passengers each summer.

They also have said it has reduced private vehicle trips through the park by nearly 2.3 million, eliminated more than 32 tons of smog-causing pollutants and resulted in a reduction of more than 21,000 tons of greenhouse gases.

BDN Writer Bill Trotter contributed to this report.

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