BART set to turn down the volume on screeching trains

Quieter BART trains are coming, BART engineers predicted on Wednesday, and the key is the simple trick of shaving about 2 millimeters of metal from the wheel of every car in the system.

The new wheel design, which BART developed with computer models, could reduce noise by as much as 50 percent when the reconfigured trains begin rolling this fall, according to BART engineering manager Ben Holland.

Holland is in charge of an ambitious project to regrind the wheels on all 669 cars in the transit agency’s fleet after models and tests revealed that doing so would lower noise by improving wheel-to-rail contact and by reducing the amount of track rippling, or corrugation, that BART cars cause when they roll down the track. The rippled track is largely responsible for the maddening high-pitched and high-decibel screeches. When the track becomes sufficiently misshapen, BART crews must regrind the damaged sections.

The change in wheel design, Holland said, is “extremely subtle.” BART wheels are now cylindrically shaped at the point that they make contact with the rails. The new design introduces a slight conical tapering into the wheels, imperceptible to the naked eye.

The design has led to noticeably quieter operation on a prototype train that BART is running on a stretch of test track in Hayward, Holland said.

The plan, Holland said, is to retrofit all existing cars with the redesigned wheels over the next two years.

BART engineering manager Ben Holland stands next to BART trains being retrofitted at the maintenance facility in Hayward. BART engineering manager Ben Holland stands next to BART trains being retrofitted at the maintenance facility in Hayward. Photo: Lea Suzuki, The Chronicle Buy photo Photo: Lea Suzuki, The Chronicle Image 1 of / 10 Caption Close BART set to turn down the volume on screeching trains 1 / 10 Back to Gallery

At the BART maintenance yard in Hayward, workers are preparing to install the new grinding apparatus onto its existing equipment. In all, more than 21,000 wheels will be modified at BART yards in Hayward, Richmond and Daly City.

In addition, the 775 on-order replacement cars for BART’s “fleet of the future” will be equipped with the redesigned wheels.

BART riders could begin experiencing the new serenity as early as December, depending on whether they are lucky enough to board a retrofitted car.

Noise, Holland said, is major complaint from long-suffering BART patrons who were promised a “swift, virtually noiseless and vibration free” system in ballot language when BART originally won approval from voters in 1962.

In other BART developments, the long-delayed Warm Springs/South Fremont Station should open in October, BART spokeswoman Alicia Trost said.

In addition, construction on the Antioch eBART extension is ahead of schedule, and that diesel-powered line from Pittsburg to Antioch could premiere months earlier than the 2018 opening previously announced.