The city of Orillia and the union representing its firefighters are headed to arbitration to settle a years-long labour dispute.

Members of the Orillia Professional Firefighters' Association have been working without a contract since December 2017.

Association President Ian Nicholson says an arbitration hearing is set for April 12. It comes after many rounds of negotiations and recent mediation.

Nicholson says wages and benefits are the sticking points.

While he would not get into specifics, Nicholson says what Orillia's firefighters are after is in line with what other Ontario fire services employees get.

Nicholson says it's "unfortunate" to have to go to arbitration to settle what he feels should have been resolved through negotiation.

The union's last labour fight with the city was also resolved by an arbitrator.

On Saturday, Mayor Steve Clarke said only that the process is used quite frequently across the province.

Clarke's comments came on the same day 58 city employees working for departments including water, wastewater, road and winter maintenance went on strike.