"We encourage everyone to plan ahead and allow more time to get where they need to go," Bay Bridge spokesman Andrew Gordon said.
BART spokesman Jim Allison urged the public to "do a little research ahead of time" so no one has to wait in line to buy tickets. He said BART expects very busy ridership while the bridge is closed, especially today, Friday.
Caltrans has closed the bridge in both directions to complete additional work that must be finished before the new eastern span can be opened to the driving public. Caltrans tentatively is planning to re-open the bridge at 5 a.m. Tuesday but there's a chance it could re-open before then if the work is completed early.
However, Gordon said Caltrans cannot promise that the span will open early, saying, "The bridge will open when it's ready."
Allison said BART is trying to fill part of the gap caused by the bridge closure by running longer trains today and having 24-hour service at 14 stations.
However, BART won't provide overnight service from Monday night into Tuesday morning because it needs to close its tracks for a short period to perform maintenance work and inspections and it's expecting the bridge to be reopened by that time, Allison said.
He said the transit agency's overnight trains are operating hourly on a modified schedule from Concord and the East Dublin/Pleasanton stations. All trains are meeting at MacArthur Station in Oakland, where passengers may transfer to reach any of the 14 stations that will be open around the clock.
He said BART expects its ridership to increase significantly because its ridership has surged by up to 30% during past Bay Bridge closures.
AC Transit spokesman Clarence Johnson said the bus agency isn't able to provide transbay service while the span is closed so its transbay buses instead will stop at four BART stations to drop off passengers going to San Francisco and pick up passengers coming from San Francisco. Those stations are MacArthur, the Oakland Coliseum, West Oakland and North Berkeley.
He said many local buses operated by AC Transit, which serves parts of Alameda and Contra Costa counties, are also bringing riders to BART stations as part of their regular service.
San Francisco Bay Ferry spokesman Ernest Sanchez said his agency has also increased its service while the Bay Bridge is closed. There is expanded service from San Francisco Bay Ferry's terminals in Oakland, Alameda Main Street, Harbor Bay in Alameda, Vallejo and San Francisco.
He said there also will be direct service between Alameda Main Street and San Francisco and Oakland and San Francisco. Normally Alameda Main Street and Oakland share a boat.
"We're staffed and ready to go," Sanchez said.