For the second time in a month, a mysterious power surge knocked out numerous BART cars Wednesday — puzzling agency officials who thought they had the problem under control the first time around, and making life miserable for commuters packed into shortened trains.
BART was able to repair some of the 25 or so cars that lost their propulsion systems on the Pittsburg-Bay Point line, but not all of them — raising the likelihood that many trains will be short of cars for the Thursday morning commute.
BART engineers worked into the night trying to find an answer for what is becoming a major problem for the aging rail system.
When the first round of problems began in late February, BART focused on a new electrical substation that had been installed a few months earlier near the Oakland end of the Transbay Tube. Wednesday’s problems, however, happened far from there — between the North Concord and Bay Point stations.
“It’s the same symptoms,” said BART spokeswoman Alicia Trost. “But we don’t know if it’s the same cause.”
About 80 cars had their propulsion systems damaged by power surges near the West Oakland Station from Feb. 20 through early March, including 40 in a single day. For days, the transit agency ran nine or eight cars on what are normally 10-car trains. BART eventually turned off the new substation, and the situation seemed to get better.
But Trost said that, in fact, the problem continued for a brief time after the substation was disengaged — leading officials to suspect there may have been another trigger.
Trost said it was too early to tell what caused Wednesday’s train-car knockouts or to say whether they were related to the earlier problem.
Wednesday’s power-surge problems forced BART to shut down train service between North Concord and Bay Point and to transport riders via a bus bridge. BART said the service between the stations is expected to stay down during Thursday morning’s commute. Delays plagued the system throughout the day.
“It was actually more crowded than usual,” said Nicole Anthony, 19, who was riding at the normally off-peak time of 11 a.m. By the time she got to the West Oakland Station, she said, “in the other trains there, it was standing-room only.”
BART maintenance crews were able to get some of the damaged cars back online Wednesday, and test trains were running on the problem section of track.
However, other knocked-out cars were still in the shop, and Trost said BART was having to strip parts from its fleet to make the fixes.
Compounding BART’s problems: It’s running out of spare parts.
“The supply is definitely an issue and a concern, and we will have to deal with that,” Trost said.
Even before Wednesday’s problems began, BART was running 16 trains during the commute hour that were short one car each, Trost said. That “likely will be worse (Thursday), since we have more damaged cars,” she said.
With a single car able to carry about 150 passengers, it’s certain to be a tight squeeze for many riders.
“This is not an insignificant problem,” said Joel Keller, a BART board member from the East Bay whose constituents include many riders of the Pittsburg-Bay Point line.
No details on problem
Keller said BART directors had received a “brief” report on the first round of power surges, but had yet to get any details on the cause.
“Enough time has gone by, by now,” he said. “If they don’t know, then we should tell the public that as well.”
BART’s latest bad news came even as officials this week welcomed the arrival of its first new train cars in years. The cars will be put into service for testing before full production begins next year.
San Francisco Chronicle staff writer Jenna Lyons contributed to this report.
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