Bay Bridge East Span Tower Reaches New Heights

October 25, 2010

Early this morning, crews on the new East Span of the San Francisco-Oakland Bay Bridge began a multiday operation to lift and install the second tier of segments for the span’s signature tower. The painstaking process involves tilting each leg from horizontal to vertical on a specially-designed barge positioned at the tower’s base, and then hoisting the legs 300 feet into the air before securing them in place.

The first leg reached vertical between noon and 1 p.m. today, and at 3 p.m. was in the process of being raised above the deck level. Each of the four legs that make up this second "lift" will take 16-20 hours to tilt, lift and bolt. Caltrans plans to work non-stop, running back-to-back 12 hour shifts, until all four legs are in place.

Bridge enthusiasts can view the operation in real time via the webcams at bata.mtc.ca.gov.

October 22, 2010

Beginning Monday, October 25, crews will hoist into place the second “lift” of tower legs for the new East Span of the San Francisco-Oakland Bay Bridge, bringing the tower construction into full view for Bay Bridge drivers. Once in place, these sections will loom more than 10 stories over the Bay Bridge, giving motorists a front-row glimpse of construction progress. Bridge enthusiasts can view the operation in real time via the webcams at bata.mtc.ca.gov.

Made up of four independent legs, each of which is composed of five vertical sections, the tower will eventually rise to 525 feet and will help give the bridge its unique design, which calls for a single cable to anchor into one side of the span’s eastern end, drape over the tower, wrap around the west end, and go back over the tower to anchor back into the eastern end.

The bottom section of the tower – which now rises to 165 feet above the water level – was installed on its foundation in July. The second set of four tower sections arrived in the Bay Area on October 9. They are 107 feet tall, each weighing 617 tons, or 1.2 million pounds. With the placement of these sections, the tower will be 272 feet tall, a little more than halfway toward its ultimate height.

Crews will work around the clock, using two 12-hour shifts, to erect all four tower shafts. It takes approximately 16 hours to lift, place and bolt each one.

The arrival of the third group of tower sections is expected in December 2010.

The East Span project is being overseen by the Toll Bridge Program Oversight Committee (TBPOC), made up of MTC’s Bay Area Toll Authority (BATA), Caltrans and the California Transportation Commission.