CONCORD, Calif. — Bay Area Rapid Transit officials believe metallic dust is to blame for mysterious power surges that knocked out nearly 24 cars in the East Bay April 14, and two similar incidents in 2016, the San Jose Mercury News reported.
BART workers first started noticing problems with the cars at around 10:30 a.m. April 14 between the North Concord/Martinez and Pittsburg/Bay Point stations, said spokesman Jim Allison. The agency ultimately switched to shuttle trains at 1:30 p.m., after the power surges had disabled 22 cars.
It’s not the first time that voltage spikes disabled BART cars. The agency dealt with similar problems in late February 2016 near the West Oakland station, and again in mid-March 2016 between the North Concord and Pittsburg stations.
The power issues afflicting the 22 cars appear to be the result of a combination of factors, Allison said. One issue is the buildup of metallic dust on the underside of cars impacted by the electrical surging, he said.
BART generates metallic dust from rail grinding, Allison said. The dust can conduct electricity, which becomes susceptible to flashes as the cars draw power from the track’s third rail.
To address the issue, Allison said BART is in the process of purchasing magnets, which will sit on cars that aren’t carrying passengers to pick up the metallic dust left in the rail grinders’ wake, a solution that could be implemented by next month.