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SAN FRANCISCO (KTVU) - BART officials say it's one of the biggest Transbay shutdowns ever planned in its history.
Starting Saturday at 6 a.m., there will be no BART trains running between San Francisco and the East Bay, as BART crews shut down the Transbay Tube for a major maintenance project.
That means riders will need to take ferries, buses or cars, which BART officials say could cause congestion and delays for anyone out on the roads.
On weekend days, BART trains shuttle about 80,000 to 100,000 riders across the Bay.
"It's going to put a hardship, especially this weekend. I was heading down into the city, so I'm not going to anymore," said Roxanne Hernandez, who regularly rides BART from her home in Walnut Creek.
"Having BART shut down on Saturday, Sunday, that's going to be a big problem," said Chase Sinai of San Ramon. He added jokingly, "I'm going to have to probably swim."
Signs have been posted at stations to warn riders about this weekend's closure from 6 a.m. Saturday through Sunday night. A second closure is planned for Labor Day weekend.
Alicia Trost, a BART spokeswoman, said they chose those weekends because there were the least number of major events in the area. She says the work on the Transbay Tube is critical.
"We are replacing a very essential component to our track. It is really one of the most important sections of track in the entire BART system," Trost said.
BART crews will be replacing an interlocking crossover on the Oakland side of the tunnel, which allows trains to switch over to a parallel track if there is a delay inside the tube. Right now, trains must come to a stop and wait, causing more delays because the crossover is too worn down to use.
The West Oakland BART station also will be shut down during the weekend. Riders will be able to take a shuttle from there to Oakland's 19th Street station, which will serve as the East Bay hub for BART's bus bridge.
BART officials say 94 buses are ready to transport riders from there across the Bay to San Francisco's temporary Transbay Terminal. From there BART riders can walk or catch a free Muni ride two blocks to the Embarcadero Station.
"It's got to be done. It's going to be an inconvenience to some folks, but I'd rather be safe instead of stuck in a tunnel somewhere," said David Collinge of Oakland.
BART officials say they will be using the closure to perform other maintenance work, cleaning, and other repairs.
For riders, there will be extra ferry service, more frequent BART trains system wide, and AC Transit buses will have Transbay service.