Commuters will be slugged with long delays on Tuesday as hundreds of bus drivers strike for 24 hours in Melbourne and regional Victoria.

The stoppage will affect 49 bus routes in Melbourne and 25 in Ballarat and Geelong, from the last service on Monday evening until the first scheduled trip on Wednesday.

Melbourne routes affected are in the west, inner east and southeast.

The Transport Workers Union (TWU) said more than 500 members would take part in the protected action as part of an ongoing pay dispute.

Members are calling for a 4 per cent raise and 1 per cent superannuation increase.

Passengers should allow for extra travel time or make alternative arrangements on Tuesday. Train, tram and bus services not operated by CDC will not be affected.

TWU said 90 per cent of members voted to take protected action after negotiations stalled with a “disrespectful and insulting offer”.

“Drivers are insulted and angry at the companies [sic] latest sub-standard EA offer – a fixed wage increase less than what TWU members have averaged for at least the last 12 years,” the union said.

CDC apologised for the “significant disruptions” expected on Tuesday and defended the enterprise agreement rejected by TWU.

A spokesperson told The New Daily previous increases were pegged to the Australian Bureau of Statistics wage index model.

“During the mining boom, those increases were high,” the spokesperson said.

“With the wage index now somewhat sluggish, CDC has offered fixed increases which is higher than the average increases that our drivers have received over the period of our last [four-year] EBA, as well as increases to superannuation – this will make our wages 25 per cent higher than the equivalent rate under the Modern Award.”

CDC offered paid parental leave and family and domestic violence leave, as well as permanent part-time options for workers transitioning into retirement or returning to the workforce.

“We believe that our offer respects the important work of our bus drivers in delivering a vital community service and is fair and reasonable.

“It is an offer designed to reflect the demands of the modern workforce and enhance our reputation as the preferred employer of bus drivers in Victoria.”

CDC was unable to predict the number of passengers affected on Tuesday.

“We are still firming up the plans to best service the bus routes during the industrial action and minimise disruptions to our customers, who have no choice than to access our services.”

Public Transport Victoria (PTV) CEO Jeroen Weimar said the stoppage could have a “significant impact” on commute times.

“This is a disappointing development, which has the potential to cause real inconvenience to many of our bus passengers, particularly as people travel during school and university holidays,” Mr Weimar said in a statement on Saturday.

“We are working with CDC Victoria to maximise the amount of services for passengers on Tuesday, but there could be a significant impact.”

He called on the operator and TWU to exhaust all avenues to resolve the dispute.

Union picket lines will be in place at Wyndham, Ballarat, Geelong and Oakleigh. Sunshine members will join the Wyndham picket.