New Bay Bridge Span Nears End of Construction

Tue December 26, 2006 - Midwest Edition

OAKLAND, Calif. (AP) Seventeen years after the Loma Prieta earthquake collapsed a section of the Bay Bridge, work crews are approaching a milestone in the construction of the new eastern span.

The replacement span’s 1.5-mi. (2.4 km) skyway section will be nearly complete when work crews use cranes to install the last of 452 giant concrete slabs that make up its deck Dec. 8.

Approximately 300,000 drivers travel between Oakland and San Francisco each day on the 4.5-mi.-long (7.24-km) Bay Bridge, which was the world’s largest and most expensive when it opened in 1936.

The bridge’s 2-mi. (3.22 km) eastern span connects Oakland to Yerba Buena Island in the middle of San Francisco Bay. Bay Area commuters still use the original, seismically vulnerable span, which was fixed after the 1989 quake caused a 50-ft. (15.24 m) section of its upper deck to collapse.

At a Stockton construction yard, the final 780-ton (707.6 t), wing-shaped slab was lifted onto a barge Dec. 5 and sent through the Sacramento-San Joaquin River Delta to the Bay Bridge construction site. The prefabrication site was set up in 2003 to produce the slabs, which average approximately 85 ft. (25.9 m) wide, 25 ft. (7.62 m) long and three stories tall.

Once the last concrete slab is in place, the skyway portion will be about 96 percent complete. Over the next year, contractors will install cables to tie the slabs together, pave the roadway and attach a steel deck that will hold a bike path.

But Bay area commuters won’t be driving on the new span anytime soon.

While the twin viaducts are almost finished, work still hasn’t begun on the single-tower suspension bridge that will connect Yerba Buena Island to the skyway extending from the shores of Oakland.

Delayed by political disputes and cost overruns, the .5-mi. long (.8-km) suspension span and its 524-ft. (159.7-m) tower are not expected to be complete until 2013.