Official: Low bridge death toll a ‘miracle’

First lady visits the site
Minnesota transportation officials spent another day dealing with scrutiny arising from a series of reports and inspections over the years that raised alarm about the bridge, including rust-eaten steel beams, missing bolts and cracks in the welding that held load-bearing parts together.

A consulting company that thoroughly examined the bridge noted that one possible fix — steel plating of fractures — carried a “relatively high cost,” according to a January report. Transportation officials deny that cost pressures swayed their decisions.

President Bush was scheduled to visit Saturday, and first lady Laura Bush toured the scene Friday morning. She praised the rescuers who rushed to the bridge in the chaos after the collapse — a sentiment echoed by the fire chief in explaining why more people didn’t die. Because the bridge was located near the heart of downtown, several emergency crews and residents were close by.

“We could not have done it as firefighters alone. It took more people than we had. It was organized. It was pretty calm,” Clack said.

'A lifesaving feature'
Authorities and engineers were in agreement that the truss-style design of the bridge played a big role in saving lives. The steel that supported the bridge was below the structure — as opposed to above the span in more traditional bridge designs.

“I think that was a lifesaving feature,” said Schofer. “They had this huge advantage. They weren’t crushed by steel.”

Clack said that even though the collapse occurred during rush hour, the heavy traffic was an advantage because the cars were almost stopped and didn’t have much momentum. Because of that, the collapse was less likely to hurl moving cars into the river.

“They didn’t have forward velocity,” he said, “so when they bridge fell, they went straight down.”

While the entire span covers 1,907 feet, only 458 feet is directly over water, supported by giant pylons. The rest of the bridge rises over sloping banks and tidal flats of the river channel.

The irregular slope of the riverbank on the south side of the bridge turned out to be a good thing. When that portion of bridge snapped at the middle, the support pylons held, and the roadway only had a short distance to fall until it was caught by a drop-off just before the river.

'A raging torrent'
On the north side of the bridge, however, the bank slopes down in a steady angle to a broad tidal flat. As a result, when that portion of the bridge crumpled, there was nothing to catch it.

That was evident to Dr. John Hick, assistant medical director for emergency medical services at Hennepin County Medical Center, who noticed that injuries on the north end of the bridge were much more grave.

Another factor that may have limited the death toll is the behavior of the river itself.

Mark Rosenker, chairman of the National Transportation Safety Board, said investigators were particularly interested in learning why a part of the bridge’s southern span shifted as it collapsed. That was the only part of the bridge that shifted, and it could help pinpoint the cause.

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Scott Bratten, who regulates locks and dams on the river for the local district of the U.S. Army Corps of Engineers, said that because of the drought currently affecting Minnesota, the water at the time of the collapse was flowing at just a third of its normal speed.

That may have made it easier for people in cars to escape them, and it almost certainly made it easier for rescuers to make their way into the water and help the dazed and injured.

“During the spring it’s a raging torrent in there and it would be a very dangerous place,” said Whitney Clark, executive director of Friends of the Mississippi River. “The low water I’m sure was a factor in not making currents very much of an issue ... If this had happened during the spring snowmelt or something it would have been a much different situation.”

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