You Can’t Just Blow Up Every Retired Bridge. Deploy the Barges!
In 1936, the newly-minted eastern span of the San Francisco-Oakland Bay bridge was the longest bridge in the world. The two miles connecting Oakland and Yerba Buena Island took three years to build, and used up 6 percent of the country’s steel.
Nearly a century later, the country is getting its investment back. Kinda. California’s Department of Transportation is in the midst of a years-long dismemberment plan, carefully removing the bridge’s steel so it can be reused. Yesterday it began one of the most impressive feats, using pulleys to lower the first of five 504-foot-long trusses onto two floating barges hundreds of feet below.
Each of these trusses has about 2,500 tons of steel in it. Simply dropping them into the water below is not an option. For one, it would be incredibly dangerous—it would be a hold-my-beer moment to end all others if the drop went awry and somehow conked into the new bridge. Somebody would also have to figure out a way to recover the span from the soft mud. And last (and certainly not least), the whole idea is a terrible, awful, environmental disaster.
So CalTrans dreamed up this pulley situation. It’s a two-day ordeal. First order of business on day one was making sure the truss latched securely onto the pulley hooks. Then ironworkers cut the truss free from the massive piers, and it spent the rest of the day in a slow motion elevator ride.
Today is all about getting the truss secured on the barges and shipping it off to Oakland for disassembly. Each day lasts anywhere from 12 to 14 hours, and high winds or heavy rain could set things back. But yesterday was pretty sunny, and the work went as planned.
Yesterday’s operation was the start of Phase II of the old Bay Bridge removal. After CalTrans removes these five 504-foot trusses, it will take out fourteen 204-foot trusses that formed the bridge’s final approach to Oakland. After that, CalTrans will move on to Phase III: Blowing up the bridge’s remaining underwater foundations. Late last year, CalTrans finished up Phase I when it blew up—or rather, blew in—the massive E3 pier in a six-second implosion.
The state is sending most of the bridge’s discarded steel to recycling plants, where it will be melted down and used to make new engineering marvels. However, 450 tons of the stuff is set aside for local Bay Area artists, who will have a hell of a time hauling it away to Burning Man.
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