Saturday trips on the Tracer public transport system will be free until the end of June.

Free trips at certain times between October and December on Tracy’s five Tracer bus routes have been credited with an increase in customers this year.

“The results have been remarkable,” said Tracy Community Service Coordinator Arlene Roberts.

City transportation coordinator Johanna Ferriera on Thursday told parks commissioners that 7,675 trips were taken on Tracer buses last month — a new March record and a rise of 15 percent from last year.

Ridership in January was up 16 percent, and it was up 22 percent in February.

Ferriera told commissioners the city has built the first of 18 planned bus shelters, which will cost between $20,000 and $29,000 each.

The first shelter was built at the corner of Orchard Parkway and Grant Line Road near the new Chili’s restaurant. More shelters are planned at such destinations as the Tracy Branch Library, Sutter Tracy Community Hospital and the Boys and Girls Clubs.

The city spends no money on the Tracer system and relies instead on federal and state grants, according to Ferriera. About 15 percent of the funding comes from bus fares.

Daily fares cost $2.50 for adults, $2 for students and $1.25 for seniors.

Ferriera said $1.1 million will be spent to increase from eight to 16 the number of “slow-fill” compressed natural gas refueling stations at its natural gas facility on South Tracy Boulevard.

Buses filled overnight by slow-fill posts can run an entire day without refueling.

The city recently purchased two new natural gas-powered buses as part of a plan to phase out diesel-powered buses by 2010. The pair has been added to the existing natural gas-powered fleet of eight buses.

Deputy Director of Parks and Community Services Rod Buchanan said Thursday that the natural gas-fueled buses keep Tracy’s air cleaner than the diesel-powered buses.

To reach reporter John Upton, call 830-4274 or e-mail jupton@tracypress.com.