Riders can find out the results of the vote Wednesday evening by visiting the Winnipeg Transit website or by calling Telebus at 287-7433. (CBC)Winnipeg bus riders are again facing the threat of labour action by city transit drivers and maintenance staff, who are voting on a new contract on Wednesday.

If the membership of the Amalgamated Transit Union local 1505 reject the contract, a strike could happen as early as Thursday, which could lead to "a complete suspension of transit services for an indefinite period of time," city officials warned Monday in a release.

"We urge our customers to consider making alternate travel arrangements," officials said.

The outcome of the vote will be posted on the Winnipeg Transit website and on Telebus at 287-7433 Wednesday evening.

Winnipeg Transit expects that Handi-Transit service would continue as usual even if a strike occurs.

In late July, the union, which represents about 1,000 bus drivers and 250 maintenance workers in Winnipeg, refused to work overtime for several days, forcing the city to cut 15 to 20 transit buses each day, affecting mostly morning rush-hour service.

On Aug. 6, a special meeting of Winnipeg city council ratified a settlement with the Amalgamated Transit Union Local 1505. All contract matters were resolved by mutual consent, except for provisions dealing with Sunday shifts for drivers, which were to be referred to arbitration.

Initially, union leadership did not believe the contract required a membership vote for ratification, but they later learned a vote was required.

The new agreement would see drivers and maintenance workers receive general salary increases of 2.0 per cent this year, 2.2 per cent next year and 3.0 per cent in 2010.

Winnipeg Transit moves more than 130,000 people each weekday, city officials said. Almost 15 per cent of Winnipeg workers commute by bus, according to Statistics Canada.

The last transit strike in Winnipeg was in the winter of 1976. It dragged on for 1½ months.