A union representing the licensed captains and officers who work on the state ferry system have rejected a tentative contract agreement.

The International Organization of Masters, Mates and Pilots voted down the proposal by mail-in ballot. Union representative Ron Bressette said he's been with the union since 1992 and has never seen a tentative agreement rejected.

Bressette declined to discuss the final tally. The union represents about 100 workers.

Bressette told KTOO that many members felt the negotiated wage increases were inadequate. They included no raise the first year, a 1-percent raise in 2015 and a 2-percent raise in 2016.

Next-step options include negotiating a new agreement and arbitration. Bressette said the union hasn't ruled out a strike.

Two other unions also have tentative agreements in place, pending ratification.