Caltrans blows up Bay Bridge pier on live TV
SAN FRANCISCO (KTVU) - It lasted a few seconds, but what a sight! Caltrans blew up a large concrete pier of the old eastern span of the Bay Bridge Saturday morning.
Caltrans had announced the implosion would occur at 7:03 a.m., but the implosion happened at 7:17 a.m., live on KTVU's Mornings on 2.
The six-second implosion was said to occur mostly underwater, but it did create a giant splash. Traffic was stopped before the implosion, as a safety precaution.
California Highway Patrol officers set up rolling traffic breaks on both directions of the new eastern span of the Bay Bridge.
"This is an active demolition site and we want to encourage the public to steer clear, stay away. We will have opportunities for you to see whatever there is to see on a live feed," said Caltrans.
"This is a highly orchestrated event with years of planning that have gone into it, and were looking at a successful completion tomorrow," said Leah Robinson-Leach of Caltrans.
Boats near the bridge were diverted to about 1,500 feet from the area.
A wall of compressed air bubbles helped muffle and lessen the shock of the implosion of the old main pier that once held up the eastern span of the Bay Bridge. 600 strategically placed explosive charges, 25 to 35 pound each, will take just six seconds to bring the massive five-story underwater structure down.
There were concerns that the implosion would cause slight delays to BART riders, as BART said it would hold trains at the Embarcadero and West Oakland stations for safety precautions as well.
Although the underground Transbay Tube is not in danger of sustaining damage as a result of the implosion, Caltrans will be collecting vibration data from within the tube during the event, BART officials said.
In the rare event that significant vibrations are detected within the tube, BART officials will conduct the same procedures and inspections they would in the event of an earthquake, according to BART.
A heavy mat will be placed on top of the pier to contain any possible debris. Fine particles will form a cloud-like plume in the water as a result of the implosion and may be visible for hours afterward, Caltrans officials said.
Caltrans chose November for the implosion because that's when there is the least impact on fish and mammals because many species, such salmon, herring and nesting birds aren't around, according to Caltrans officials.
Noisy active deterrent devices will scare birds away from the blast zone. "Passive" noise devices. which make annoying under water sounds, will ward off sea mammals such as seas, dolphins and whales.
"If a mammal did, in fact, come up, then there would be a time frame in which to determine if that mammal was out of the area, Or, if it was in that area, then a decision would be made as to whether we would move to our second window of opportunity," said Robinson-Leach.
Although many fish species will most likely be killed during the implosion, officials with the San Francisco Bay Conservation and Development Commission said it would cause less environmental damage than other methods of demolishing the pier.