A member of BART’s board wants to roll back fare increases that have already been approved, insisting that higher ticket prices will chase more riders away from the transit system.

Director Debora Allen of central Contra Costa County is lining up support to stall a 5.4% hike planned for January, which would add about 40 cents to a long trip from Antioch Station to Embarcadero — producing $25 million a year for the struggling agency.

“If I’m a private business and I’m not serving my customers to their satisfaction, I can’t raise my prices because people will look for other alternatives,” Allen said.

The same holds true for BART, she added, pointing to the transit system’s flagging approval rating and the steady drumbeat of complaints about grime, drug use and panhandling.

Allen said she will make a motion at the June 13 meeting to pull next year’s fare increase from the current budget and reconsider it next year. She’ll also request that the board postpone its vote on a subsequent batch of fare hikes, which would raise the price about 16 percent between 2022 and 2028, generating funds for major infrastructure to carry more people through the Transbay Tube.

She says that if BART keeps ticket prices stable and focuses on cleaning the system, it may stanch a ridership bleed-off that has cost the agency 3.4 percent of passengers since 2016. And it may eventually lure back people who’ve turned to ride-hail services or ferries for a more comfortable rush-hour commute.

“I think it’s unfair to keep raising fares when we’re struggling to keep riders, and we’re struggling to maintain quality of life on the system,” Allen said. “I’m not sure how much riders will take.”

But the idea alarms transit officials, who note that BART would lose funding for new rail cars and other infrastructure if its board pulls the plug on next year’s fare hike. The agency aims to run longer, more frequent trains through its Transbay Tube, boosting capacity from 27,000 passengers per hour to 39,000.

Subsequent fare hikes would go toward a mix of capital projects and day-to-day operations, such as janitors or police officers. The increases would reap about $400 million over eight years, said Assistant General Manager Pamela Herhold, providing vital nourishment for a system that’s limping along on old equipment.

Most of the capital projects that BART tied to the fare increases “are already well under way,” Herhold said. In 2012 the board signed a $2.5 billion contract to purchase 775 rail cars from Bombardier, and BART officials hope to award a train control system contract in December. Funding for the project already looks precarious: BART sought a $1.25 billion grant from the Federal Transit Administration, but its application has languished in Washington for 18 months.

If the board turns off another funding spigot, BART would have to find the money elsewhere.

“Right now we don’t have a backstop,” Herhold said.

The issue is stirring tension among board directors as Allen tries to rally a five-vote majority. Known as the board’s conservative voice, she represents the needs of suburban commuters who complain they are being shafted as BART evolves from being a commuter rail to an urban metro.

In some senses, attitudes appear to be shifting in Allen’s favor. Other directors have raised questions about BART’s tanking approval rating and its ability to manage irritants like drug use and panhandling.

Director Liz Ames, in particular, is skeptical of fare hikes. Like Allen, she’s perturbed by the slump in ridership at a time when demand should be escalating. The Bay Area’s economy is growing, and more people need to commute from the East Bay to jobs in San Francisco. The boom has showered more sales tax and property tax money on BART as the system expands farther into the East Bay and inches toward Silicon Valley. Over the last two years it opened new stations in Warm Springs and Antioch, and it is planning an extension into San Jose.

Yet the average number of weekday riders dipped during that period, from a high of 440,000 in 2016 to 425,000 last year.

“I don’t feel comfortable increasing fares at a time when ridership is dropping,” said Ames, who represents the Fremont and Warm Springs areas. “Debora (Allen) and I are in alignment on this.”

Other directors stress the importance of financial stability. In the past, BART would wait for years to raise ticket prices, then jolt riders with dramatic bumps. The agency jacked up fares by 30 percent in 1986, then by 45 percent between 1995 and 1997. It wasn’t until 2006 that officials saw the importance of slow, predictable increases to keep up with inflation.

Since then, BART has gradually squeezed riders, taking an approach that allows managers to do long-term planning. It’s also impressed the credit rating agencies on Wall Street. BART has a “very strong credit rating,” Herhold said, which could be imperiled if the board directors don’t stick to the fare hike program.

That element of financial uncertainty disturbs board President Bevan Dufty, one of the key officials Allen hopes to persuade. He said the unstable pricing methods of the past — coupled with other bad decisions — caused BART to slide into its current dilapidated state.

“If we start delaying fare increases, that could call our financial health into question,” Dufty said. “And I’m just not inclined to go down that road. I understand riders are frustrated, but I think our responsibility is to bring them a world-class system.”

Director Robert Raburn, of Oakland, called Allen’s motion “a noble goal that would require a whole slew of cuts” — possibly to train service, custodians or police officers. He was also wary of sending BART’s credit rating down the tubes, given that the board is set to issue hundreds of millions in bonds on June 13, the same day it weighs the fare hikes.

Allen’s motion is likely a long shot if she can’t turn Dufty or at least one member of the board’s more urban, progressive wing. But she’s already put together another pitch: she and Ames will ask the board to divert $35 million from big infrastructure projects, and instead use it to make a more secure environment for customers.

Namely, they want to raise railings throughout the system and put the elevator inside at Coliseum Station, to block transients and fare cheats from coming in. Additionally, they want to take $2 million from the operating budget and devote it to scrubbing.

But even that plan will likely hit opposition. Raburn recoiled at the idea, saying BART’s budget is too tight to start swapping money from one project to another.

Dufty agreed.

“I’m not going to ghost the unglamorous, important work to do something that sounds snazzy in the moment,” he said.

Rachel Swan is a San Francisco Chronicle staff writer. Email: rswan@sfchronicle.com Twitter: @rachelswan