Implementation of the Median Barrier on the Golden Gate Bridge
The Golden Gate Bridge was closed to vehicle traffic this past weekend for the installation of new safety system to address crossover collisions. The Moveable Median Barrier (MMB) system includes about 13,340 feet of barrier consisting of 12-inch wide and 32-inch high steel clad units filled with high density concrete tightly pinned together to form a semi-rigid median barrier. The system also includes two barrier transfer machines, aka “zipper” trucks. The installation of the one-foot wide MMB should virtually eliminate crossover collisions.
The project budget is estimated at $30.3 million with funding coming from three sources: $20 million (76%) from the Metropolitan Transportation Commission via the State of California; $1,379,200 (5%) in federal funds; and $5,120,800 (19%) from Golden Gate Bridge toll revenues.
A new driving experience after installation
With the installation of the moveable median barrier comes a new and different driving experience across the Golden Gate Bridge. Today, plastic tubular pylons are used to separate opposing lanes of traffic on the Bridge. The new barrier system will provide a safer and more efficient system of dividing opposing lanes of traffic.
The barrier was installed on the 1.7-mile-long Bridge and on the approach portion of Highway 101, north of the Golden Gate Bridge, starting at Alexander Avenue. Using transfer machines, the barrier will be moved several times a day to create more lanes in a particular direction to accommodate variable traffic demands such as the morning and evening commutes.
A new merge will be very different for southbound vehicles. Where drivers current merge from left to right, the new merge will be from right to left. In addition, the speed limit will be dropped to 45 miles per hour from the current 55 miles per hour on the descent down the Waldo Grade. Lastly, with the installation of the barrier, the two inside lanes will lose 6-inches of width. Getting used to driving next to the barrier may take some adjustment for some drivers, and the District advises motorists to take it slow and get used to the new driving conditions.
This new moveable median barrier system will enhance safety by reducing the potential for cross-over collisions and will allow the Bridge District to more efficiently reconfigure lane changes to optimize traffic operations on the bridge.
To view an animation of the new driving experience, click here.
For more information on the Moveable Median Barrier project, click here.