[WestSylvanian]

I agree about terrorism. People on the bridge reported hearing jackhammer-like sounds before the collapse. Multiple explosions of charges under the supports? Even earthquakes don’t cause this much damage all at once.

[finnman69]

People on the bridge reported hearing jackhammer-like sounds before the collapse

Probably the sound of steel beams and connections ripping apart.

[capt. norm]

I agree about terrorism. People on the bridge reported hearing jackhammer-like sounds before the collapse. Multiple explosions of charges under the supports? Even earthquakes don’t cause this much damage all at once.

I have a friend who has retired from the demolition business and he says all it would have taken to do this would be some shaped charges, as close to the water level as possible. When they detonate, they are not very loud, and they make a "clean cut" like what happened this afternoon.

[sten]

my thoughts exactly. relayed charges detonated in sequence

i'm just hoping the homeland security types are thinking paranoid and put some divers in the water at the base of the dam (both sides).. and quickly

i'm not sure if there is anything else in the area that would add to the tragedy

[null and void]

People on the bridge reported hearing jackhammer-like sounds before the collapse. Multiple explosions of charges under the supports?

Or more likely the sound of rivets popping one by one. As soon as a critical rivet failed and dumped it's load onto surrounding rivets the whole structure would start to unzip.

I think terrorism is unlikely as a terrorist would run the risk of anyone on the construction crew spotting something amiss, and would do his dirty work in a less observable location.