A bus system that serves the city of Columbia in Howard County -- and that looked like it was rolling toward extinction because of a lack of funds -- will be on the road for at least two more years.

The Columbia Council, which directs the Columbia Association, a quasi-governmental entity that manages much of the town's affairs, has agreed to help pay for the continued existence of ColumBus, a system that serves about 650 passengers a day in the sprawling city between Washington and Baltimore.

Service will continue through June 1987 so taxpayers and voters can quiz candidates for the Howard County Council and county executive about the need for a county subsidy, Columbia Association President Padraic Kennedy said last week.

Kennedy said the association wants the county to pick up the tab for the local cost of ColumBus -- $89,000 of the $492,000 budgeted for the service this year -- because ColumBus riders are county taxpayers.

The remainder of the cost is paid by state and federal subsidies.

County Executive Hugh Nichols, who cannot seek reelection, refused to add the bus service as a recommended budget item and told Columbia Association members last year that a special taxing district should be formed in Columbia to pay the cost.

Kennedy said the association, which collects an annual fee from Columbia's 56,000 homeowners and has helped pay for the bus system since 1967, decided in March to continue underwriting the service until election time so that voters can choose candidates based on their support for the system.

"It should be an issue," Kennedy said. "And we wanted to give people a chance to decide the importance of the service."

With its decision to continue service, the Columbia Council also agreed to extend the service to the village of Columbia known as King's Contrivance. That service will begin in August, Kennedy said.

Most of the system's daily riders use the service to shop and to commute to work and school, said Jeff Barnett, director of transportation for the association.

About 12 percent of the riders are elderly, he said.

"The Columbia Council really just decided these people needed the service," Barnett said.

"And it was a decision that the Columbia Association is supportive of public transportation," Barnett added.