plus timetable and train order.

Dumbarton probably was never busy enough to, like highway draw bridges, stay closed (available for train traffic) until called (by radio or horn) for opening by marine traffic. Some draws Back East on the NE Corridor are like that, though.

One does wonder how the state managed to get the San Joaquin River permanently closed to water traffic, so I-5 would not need a drawbridge between Tracy and Lathrop. That seems like a rare event. The old drawbridges at that location are still in place, but no longer need to be operable. [www.google.com]