Watch Part of the Old Bay Bridge Implode
— TransportationAgency (@ca_trans_agency) November 14, 2015
Just after a lovely sunrise, a series of muffled booms shot across the San Francisco Bay, and a plume of water swallowed a huge chunk of the old Bay Bridge.
The chunk was once the E3 pier, a 20 million-ton concrete strut that reached from the water’s surface to the a foundation 50 feet below. At 7:18 am this morning 60,000 pounds of dynamite crumbled it into a hollow cylinder encased in Bay mud.
And the crowd went…well, not quite wild. It seems many of the spectators—more than 50 cars were parked along the shoreline—were under the impression that this implosion would be some of the arching steel spans still suspended high above the Bay. When I pointed out the E3 Pier, barely distinguishable from the pair of low, flat barges on either side of it, to Kurtis and Pam Hebel of Alameda, they seemed shocked. “Everybody here came to see the old bridge come down. This is bullshit,” said Kurtis.
Those two barges were a key part of the joy-killing efforts to conserve local wildlife. A series of hoses deployed from each sprayed the underwater portion of the pier in bubbles. “The bubble curtain is to contain the shock wave from the implosion,” said Leah Robinson-Leach, CalTrans’ spokesperson for all things San Francisco Bay Bridge. To further spoil the fun (or protect people and structures safe from flying debris, again, depending on your perspective), the 80-by-140 foot rectangular top of the pier was covered by a huge steel and wood mat.
Taking down a bridge, or even a piece of it, is a huge friggin’ hassle. Besides the Coast Guard and Sheriff maintaining perimeter patrol, dozens of scientific survey boats made sure fish and wildlife were clear of the blast zone. After the dust settles (should be about 24 hours), they’ll do some diving to make sure all the concrete made it safely down into the caisson hole in the mud.
In all, the E3 Pier cost $20 million to implode. (Demolition costs for the whole bridge crest $190 million.) This project was unique, not just because E3 was the largest of the old Bay Bridge’s supports. CalTrans and its partners in destruction will look at wildlife impacts, water pollution, and how far the sound propagated underwater to determine whether to use explosives to remove the rest of the old Bay Bridge’s 21 remaining piers. “The scientists and engineers will be evaluating the results over the next week,” says Robinson-Leach.
Even if all that protection kept the crowd from seeing a Las Vegas-style hotel collapse, they still got some water spouts worthy of Pirates of the Caribbean. And some spectators had arrived with lowered expectations. “We learned earlier this week that we would probably see nothing,” said Randolph Trasviña, who—along with his friend Chip Fong—woke up at 3am to drive to Treasure Island from Sacramento. So, why bother? “We’re retired,” said Fong with a shrug.