A popular summer trolley tour of the Bath Iron Works shipyard has been canceled for at least a year because of safety and security concerns as the military shipbuilder plans to build four destroyers and a new outfitting hall.

Amy Lent, executive director of the Maine Maritime Museum in Bath, which has been conducting the behind-the-scenes tours since 2006, said the cancellation will be a letdown for many visitors.

“It’s a huge disappointment not to be able to operate that tour,” she said. “They’re extremely popular – every tour sells out.”

BIW, a subsidiary of the Virginia-based defense and aerospace firm General Dynamics, is scheduled to begin work this year on a $32 million project to build a new outfitting hall. The project will include demolition of various older buildings and upgrading other shipyard facilities.

In addition, work on four ships will be going on simultaneously in the yard: two Zumwalt-class destroyers and two Arleigh Burke-class Aegis destroyers, the company has said.

BIW spokesman Matt Wickenheiser said that is simply too much work going on at once to guarantee that both tourists and company employees would remain safe.

“Our main concern is that we’re going to be ripping up the shipyard and doing a lot of work,” he said.

BIW representatives said it was too soon to know whether the behind-the-scenes tours could be resumed as early as summer 2015.

The shipyard tours are a centerpiece of the nonprofit museum’s summer programming and a major source of its revenue, Lent said. However, another tour is being developed as an alternative, she said.

It is likely that the replacement tour would involve visiting several historic sites in Bath and focus more on the city’s long history of shipbuilding, Lent said.

Information about those tours will be posted on the museum’s website, MaineMaritimeMuseum.org, as soon as it is finalized, she said.

In addition, she said the museum’s Kennebec River cruises will be adjusted to provide added emphasis on BIW, particularly the massive DDG-1000 Zumwalt destroyer currently sitting in the water at the shipyard’s edge.

“The DDG-1000 is an amazing ship, and seeing it from the water is astonishing,” Lent said.

Prices for this year’s tours have not been finalized, she said. In 2013, the museum charged $35 to nonmembers for the 90-minute BIW shipyard tour and $25 for the 60-minute Kennebec River cruise.

Tours generally run from May through October, Lent said.

J. Craig Anderson can be contacted at 791-6390 or:

canderson@pressherald.com

Twitter: @jcraiganderson