Veolia, a company under TransDev, shuttles people living in the South Shore communities of Ste-Julie, St-Constant, Ste-Catherine, Delson and others.
The communities affected by the strike called in a private company to replace the Veolia drivers who shuttle people between the South Shore and Montreal.
Buses are supposed to be running on those lines during rush hour times. Earlier on Wednesday, some union members formed picket lines to prevent buses from leaving stations.
Police intervened at the Delson station around 6 a.m. Wednesday to allow the bus to leave.
In Ste-Julie, workers on strike are causing minor delays to the bus routes but are allowing buses to exit the station.
Stéphane Lacroix of the drivers’ union said the issue is wages.
"There’s a 10-15 per cent difference between the workers of TransDev and Veolia compared to the other workers who are doing exactly the same job elsewhere on the South Shore," Lacroix said.
Service to and from Montreal is supposed to continue as usual, but service between communities on the South Shore may experience delays.