NTSB: Driver heard 'horrendous boom' then Skagit bridge collapsed

NTSB: Driver heard 'horrendous boom' then Skagit bridge collapsed
A portion of the Interstate 5 bridge is submerged after it collapsed into the Skagit River dumping vehicles and people into the water in Mount Vernon, Wash., Thursday, May 23, 2013 according to the Washington State Patrol. (AP Photo/Skagit Valley Herald, Frank Varga)

WASHINGTON, D.C. - The driver of the truck that struck the I-5 Skagit River Bridge - causing it to collapse - says he heard a "horrendous boom" when he made contact with the bridge truss.

The driver's account is included in a voluminous National Transportation Safety Board report on the bridge collapse on May 23, 2013.

William Scott was driving the oversize truck-tractor and flatbed trailer that struck the underside of the truss just before the span collapsed. He told NTSB investigators he moved to the right when a passing truck crowded him.

From the NTSB transcript, dated May 25, 2013:

"I remember the truck, the other truck, being right there, like on my window. And he never stopped, right. When the - when things went wrong, I got on the brake pedal trying to stop it, and it wasn't - it was slowing down, but it just was hard to hold on and do everything, right?

"And then we coasted out the other side of the bridge. And I coasted out, came to a stop on the shoulder where the truck is now. And there was an older fellow stopped with his car and his wife, and came back and said we had just made it. And I said, just made what? And he said the bridge fell back and there's people in the water."

Two passenger vehicles fell from the bridge deck into the Skagit River. There were no fatalities.

Scott told investigators  the other truck "squeezed" him as he was approaching the bridge. He said he moved over, but had no indication the bridge clearance was too low to safety clear the bridge.

Again, from the NTSB transcript:

"And we were into the bridge and all of a sudden it - was just a horrendous boom and things were - it was violent in the cab. And you can see the inside of the cab. I'm not a messy guy, but my stuff was everywhere in there."

Scott told investigators he was well rested and in good health at the time of the collision.