SAN FRANCISCO (CBS SF) — A controlled, underwater implosion just after noon on Saturday took out a massive support pier of the old Bay Bridge eastern span.

Caltrans said the blast used some 8,000 pounds of explosives and the process — part of a years-long dismantling effort — took about three seconds.

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Another pier was imploded last November and Caltrans claimed no fish were killed in the blast, demonstrating that a “bubble curtain” of air blown around the pier proved successful in protecting marine life from the blast of about 400 small explosives set in concrete.

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After this October’s implosions, there will be 13 remaining pier structures that need to be removed.

Six will be removed by next fall, Caltrans said, the rest will be removed in 2018.

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Pier Implosion View from Treasure Island

The blast viewed from Treasure Island. (Caltrans)

Old Bay Bridge Pier Implosion

An animation
showed how explosive charges will bring down the old Bay Bridge pier. (Caltrans)