Maybe you haven't heard, but due to a snapped cable during yesterday's evening commute, the Bay Bridge is closed today. And possibly tomorrow. It's closed indefinitely. Anyway, 511 has a list of Bay Bridge alternatives.
BART: will run long trains tonight and end service at normal times. Will run longer trains all day on Wednesday, October 28, beginning at 4 am.
AC Transit For the Wednesday morning commute, AC Transit will run regular weekday service, however buses will detour to four East Bay BART stations so that passengers can continue to San Francisco on BART. 800 All Nighter service will will operate on its regular schedule, but will go over the San Mateo bridge with the last bus leaving at 4:00 am Wednesday morning. AC Transit will operate as close to schedule as possible, but the re-routing may cause some delays.
Alameda/Oakland Ferry: will run ferries every 30 minutes from 6 am - 8:45 pm on Wednesday, October 28.
Alameda Harbor Bay Ferry: will run regular schedule on Wednesday, October 28.
Golden Gate Transit (Ferries): will have one extra high capacity ferry from Larkspur after 7 am on Wednesday, October 28.
Golden Gate Transit (Buses): will continue normal service and operate as close to schedule as they possibly can, given projected traffic.
Vallejo Baylink Ferry / Bus: bus 200 will be re-routed over SR 37/San Rafael Bridge.
Muni: route 108 to Treasure Island is running normal service.
Amtrak and Capitol Corridor
Amtrak: will operate a shuttle between the San Francisco and Martinez Stations for Coast Starlight and California Zephyr passengers. Advises San Joaquin and Capitol Corridor passengers to connect with BART at Richmond.
Caltrans Bay Bridge Bike Shuttle Service canceled Wednesday, October 28. Consider taking BART and locking your bike at the BART stations, as trains are likely to be crowded.