The countdown to the four day closure of the Bay Bridge is on.
Caltrans crews have been working all summer to get ready for the Labor Day event that will affect tens if not hundreds of thousands of people beginning Thursday evening Sept. 3 at 8 p.m. The bridge is not scheduled to reopen until Tuesday, Sept. 8 at 5 a.m.
The closure has been in the planning stages for years. Signs as far away as San Jose are already lit warning drivers they can't use the bridge on the holiday weekend.
The massive construction project, which has been happening just off the current Bay Bridge span, is aimed at increasing the seismic safety of the eastern span. In a matter of days, a chunk of the bridge will cut out and a new section will be added.
The project has been described as a high-wire act 150 feet in the air that will involve thousands of tons of concrete and steal with mere inches to spare.
During the closure, crews will cut out a 300-foot long, 3,300-ton section of the bridge and replace it with a slightly heavier section that will serve as a temporary connector ramp.
The detour will last three to four years and will reroute traffic around construction to the new span on Yerba Buena Island.
The project is so precarious there is a small chance it could get pushed by a week if the weather doesn't cooperate. High winds would make it impossible for the engineering marvel to become a reality.
Caltrans has hired a production crew to shoot the weekend project so you will be able to get an up close look at everything that is happening.
Once the work is complete, drivers will immediately experience two big changes. One is driving on the new stretch of road. The other is a new speed limit which will be reduced to 40 mph. So get ready to keep your eyes open and slow down starting in September.