PORTLAND — The Casco Bay Transit District Board has agreed to accept an arbitrator’s findings in its contract dispute with 31 workers and now it’s up to the union to decide whether to sign a deal after two years without a contract.

The board voted unanimously to accept the arbitrator’s report on salary, insurance, pension and minimum pay matters, but the findings are non-binding. The arbitrator’s report will not be made public until mid-April.

The contract with United Marine Division Local 333 expired two years ago, said Hank Berg, a spokesman for the district, which provides ferry service between Portland and several islands in Casco Bay, as well as tour, cruise and charter services.

The union represents 23 boat captains and deckhands, Berg said. Eight shoreside employees are also in the union and covered by a separate contract, but those contract provisions mirror the ones for the captains and deckhands, he said.

Under Maine state law, arbitration is required when contract negotiations between a public employer and employees reach an impasse. Berg said if the union does not accept the arbitrator’s report, the two sides will go back to negotiations but the district could declare an impasse and impose its last contract offer.