Roadway Configuration / Reversible Lanes

The Golden Gate Bridge has 6 roadway lanes. Northbound and southbound traffic are separated by a moveable median barrier, which permits the number of lanes allocated to north or southbound traffic to be changed to accommodate heavy demand in either direction, to respond to unusual traffic conditions, and to balance lane availability with real-time traffic demand to the extent possible. This ability to change the number of lanes serving a given direction is called reversible lanes. Reversible lanes were inaugurated on the Golden Gate Bridge roadway on October 29, 1963.

MORNING COMMUTE PERIOD: During the weekday morning commute period, Bridge traffic is predictably heavy in the southbound direction and light in the northbound direction. The roadway is generally configured with four (4) roadway lanes for southbound traffic and two (2) roadway lanes for northbound traffic.

AFTERNOON/EVENING COMMUTE PERIOD: During the weekday afternoon commute period, balancing lane availability to match demand is more challenging. Northbound commute traffic is more variable and spread out over a longer period of time than the morning commute, while southbound traffic during the PM commute has increased over the last several years. Lanes will be configured as followed:

  • Mondays: Three (3) northbound and three (3) southbound lanes.
  • Tuesdays/Wednesdays/Thursdays/Fridays: Four (4) northbound and two (2) southbound lanes from 4:00 p.m. to 4:30 p.m. (Note: because it takes 30 minutes for the zipper trucks to complete a lane conversion, the process begins 30 minutes prior to 4:00 p.m.—at 3:30 p.m.—and concludes 30 minutes after 4:30 p.m.—at 5:00 p.m.) At other times, lanes are configured three (3) northbound and three (3) southbound.

Motorists should know that unexpected changes to this configuration may be necessary, based on emergencies, accidents, or unusual traffic conditions. Deviations from these patterns will be sent via Twitter notifications from @GGBridgeAlerts. We will carefully monitor impacts on southbound traffic and will evaluate the effectiveness of these measures regularly.

WEEKENDS: On weekends, traffic volumes can often be very high in both directions at the same time requiring a three (3) lane configuration for each direction.