Complaints of no one using a light-rail line after it is built are familiar to Jim Mills, chairman of the San Diego Mass Transit Development Board.

Ten years ago, the board was a lone supporter of light rail in its community. Among its opponents were city hall and various chambers of commerce."The critics said you can build what you want to, but in San Diego people drive cars," Mills told a group of local government officials, engineers, planners and others Friday at a Utah Transit Authority's symposium on mass transit and land use planning.

Mills recollection brought grins to the faces of those gathered at the luncheon speech who have heard the same dire predictions for UTA's proposed light-rail line in Salt Lake County.

"It's an easy argument . . . that people are in love with their cars. Maybe they are, but maybe we haven't given them a choice," Mills said.

In short, Mills and the transit board he created as a California legislator proved the critics wrong. Ridership exceeded projections its first week of operation, he said.

"Now, the support is enormous. The only dispute now is who gets the next line."

Mills commended UTA's strategy of purchasing an existing railroad right-of-way for the rail route, and beginning its system with one light-rail line that buses will feed, then branching out where it will work.

He said San Diego followed the same plan. Purchasing an existing rail track reduced the cost of negotiating with hundreds of landowners to purchase a right-of-way. And transit operators saw bus ridership "skyrocket," particularly routes that intersected with the rail, after the first 15-mile line started operating.

Light rail works in some areas and won't work in others, so planners must determine the corridors that are best served by either rail or bus, Mills said. "If there is a corridor that warrants only lousy bus service don't provide any service."

Concerning the election UTA must hold in Salt Lake County to raise its share of sales tax by a quarter cent, Mills recounted his agency's campaign to increase its tax revenue by a half cent in 1987.

He said transit officials avoided radio and television advertising in its campaign so that the media wouldn't be obligated to broadcast opposing points of view.

Instead supporters used direct mail, customizing its mailings to address the impact mass transit would have on specific communities.

"We had 1 percent of the tax increase going toward bicycle routes, which bought us more than 1 percent of the vote," Mills said.