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TRANSACTIONS NEWSLETTER ONLINE

April-May 2009

East Span Construction Almanac 

With Skyway Complete, Region’s Attention Shifts to the Marquee Span and Tower

This will be a banner year for the new East Span of the San Francisco-Oakland Bay Bridge, as the structure’s marquee element starts to rise from the Bay waters: the daring and dazzling self-anchored suspension span, referred to as the SAS. MTC’s Bay Area Toll Authority (BATA) is one of three partner agencies overseeing the seismic safety project under the umbrella of the Toll Bridge Program Oversight Committee, which also consists of Caltrans and the California Transportation Commission. BATA also is financing the $5.7 billion project with bridge toll funds. Here’s an update of what’s happening, and how you can view the action.

It Takes a Massive Crane to Build a Monumental Bridge

The Left Coast Lifter steams past Yerba Buena Island on its way to the job site, visible just beyond the island: the gap between the already completed East Span Skyway and the Yerba Buena Island tunnel. (Photo: © 2009 Barrie Rokeach  www.rokeachphoto.com)

They don’t call it the “Left Coast Lifter” for nothing. The immense, barge-mounted crane that slipped under the Golden Gate in March will be used to help lift into place monstrous tower and deck sections for the self-anchored suspension span, referred to as the SAS.

The barge-crane combo is an engineering attraction in its own right, weighing in at a whopping 6,650 tons, reaching 328 feet into the sky when its apparatus is fully extended and capable of hoisting 1,873 tons.

And like the bridge it is helping to build, the “Left Coast Lifter” is international in its heritage, with the barge built in Portland, Ore., then shipped to China for fitting with the crane, which was custom built at Zhenhua Port Machinery Co. Ltd. (ZPMC) in Shanghai. In February the barge-mounted crane was placed on a ship for the month-long return trip to the “left coast” of the U.S. and its final destination at the East Span construction site.

The crane was put to work shortly after arriving at the Port of Oakland, unloading steel from China for the temporary support structures for the new signature span. This is just a warm-up for the heavy lifting it will do out in the Bay near Yerba Buena Island starting in mid-May, first hoisting temporary trusses, and eventually raising all 28 deck units of the new span’s permanent roadway  as well as the lower sections of the steel tower.
— Brenda Kahn & Karin Betts

Tricky Traffic Shift to Close Bay Bridge Over Labor Day Weekend

Crews are working round-the-clock to finish the traffic bypass, shown just to the right of the existing bridge. (Photo: Bill Hall, Caltrans)

The San Francisco-Oakland Bay Bridge will be closed in both directions over the Labor Day weekend in September 2009 to accommodate an operation critical to the construction of the bridge’s new East Span. Crews will use the opportunity to slice out a double-deck chunk of the existing East Span that is the length of a football field, and slide in a new double-deck piece that will shift traffic to a temporary bypass.

The maneuver echoes a similar deck removal and roll-in that took place over Labor Day weekend 2007.

“This is a massive operation,” said Caltrans spokesperson Bart Ney. “We’re talking about moving nearly 7,000 tons of steel, 150 feet in the air.” The traffic shift will clear the way for crews to eventually hook up the new East Span with the Yerba Buena Island tunnel.

Crews are currently at work seven days a week, 20 hours a day finishing the detour viaduct and building the temporary support structures that will be used to roll the old bridge truss out and the new one in over the holiday weekend. Over the months to come, the new tie-in truss section and a movable support system will take shape south of the existing bridge at deck level, 150 feet in the air. Most of the half-mile-long, double-deck viaduct detour is already observable to motorists on the bridge.

MTC is working with Caltrans and local public transit agencies to ensure mobility options for transbay travelers. BART will run all-night service to select stations over Labor Day weekend, and extra vessels will be deployed to expand ferry service on select routes.
— Karin Betts

As Labor Day weekend nears, MTC’s 511 phone service and 511.org Web site will be the official source for transit information and traffic conditions. Construction updates also will be posted on www.baybridgeinfo.org.

Bridge Views Galore

Now you can check progress on the new East Span tower section without leaving your desk and share the image with friends via e-mail or a text message.

If you’ve crossed the existing East Span of the Bay Bridge lately, you’ve probably caught tantalizing but frustratingly fleeting glimpses of cranes and construction activity on the new self-anchored suspension span (SAS). Now there’s a way to savor the experience, up close and virtually. A trio of stationary cameras are taking shots at regular intervals and beaming images to MTC’s Web site.

Not only can you view the construction live and in real-time, you can go back in time to view construction progress as of any day since early October 2008. A virtual joystick allows you to zoom in on the work and workers, and to pan across the image. You can toggle to a panoramic option that provides a nearly 360-degree view of the construction zone and the impressive sweep of the already completed East Span Skyway that stands expectantly, ready for the day when it will link to the SAS.
— Brenda Kahn

View at bata.mtc.ca.gov.

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