The Golden Gate Bridge reopened Sunday evening more than six hours ahead of schedule after crews installed a moveable concrete and metal barrier.
Golden Gate District spokeswoman Priya David Clemens said the bridge reopened at 9:30 p.m., six and a half hours early.
The bridge had been closed since midnight Friday night and was scheduled to reopen at 4 a.m. Monday so construction crews could install the 11,500-foot, $30 million barrier, which is intended to prevent head-on collisions.
During the closure, crews installed more than 3,500 individual units, each weighing 1,500 pounds that are pinned together to form a chain.
David Clemens said the barrier will be used to manage traffic flow, similar to the plastic pylons that have been used on the bridge since 1962.
"Zipper trucks" will shift the barrier to create the appropriate lane configuration, which will continue in their usual pattern, David Clemens said in a statement.
David Clemens said crews may continue to train with the zipper truck overnight but the bridge will be set up with a four-lane southbound and a two-lane northbound configuration for the Monday morning commute.
In addition to installing the metal and concrete barrier, crews modified the merge in the southbound lanes of U.S. Highway 101 on the Waldo grade, from the Waldo Tunnel approaching the bridge, David Clemens said.
Drivers will now merge right to left, instead of left to right, she said. The speed limit has also been lowered from 55 miles per hour to 45 miles per hour