BATH, Maine — A Bath Iron Works spokesman on Thursday confirmed that the shipyard will lay off 118 workers effective Dec. 20.

The layoffs — including 50 preservation technicians (painters), 27 pipefitters and 41 shipfitters, were announced to Dan Dowling, president of Local S6 of the Machinists union, just after noon Thursday.

Dowling said approximately 300 union members have been laid off this year, and added that if these layoffs go as planned, “Seven to 8 percent of our membership will be on the street.”

“We hate to do this,” said Jim DeMartini, spokesman for BIW, which employs approximately 5,350 people. “It goes without saying that between now and the [20th], we will be looking to see if we can find jobs for some number of these folks.”

DeMartini said the layoffs result from “insufficient work for the people currently in those trades.” He added that the layoffs are not the result of automatic spending cuts, also known as sequestration, because current contracts are already funded. The layoffs have not delayed the delivery of any ships, he said.

The shipyard has made a number of layoffs over the last several months. It laid off 42 insulators and pipe coverers in October, and on Nov. 1 announced it would lay off 39 pipefitters effective Nov. 18.

On Nov. 7, BIW announced that 81 employees — 41 shipfitters, 12 preservation technicians, 16 outside machinists and two metal preparation technicians — would be laid off. Jobs were found for some of those employees, although DeMartini could not say Thursday exactly how many.

Also this week, the Department of Defense announced that Bath Iron Works was awarded a $73.9 million contract modification to provide design, planning and material support services for the maintenance and modernization of Arleigh Burke-class (DDG 51) guided missile destroyers and Oliver Hazard Perry-class (FFG 7) guided missile frigates.

The contract encompasses maintenance and modernization for both classes of ships, DeMartini said, noting that the modification “is not new work for us.” BIW has been the planning yard for the DDG 51 destroyers since the mid-1980s, according to DeMartini, and in the mid-1990s was designated as the planning yard for the frigates.

On Wednesday, Department of Defense Secretary Chuck Hagel announced that a $1 billion cut in the Pentagon budget between 2014 and 2019 would trickle down to jobs cuts and reductions in contracts with private companies, CNN reported.

“We’re not aware of any specific impact as a result of that [announcement],” DeMartini said. “What we’re concerned about is stability in ship procurement and our ability to predict and plan for the future.”