An eight-lane steel bridge on interstate 35 collapsed during evening rush hour. Dozens of cars plummeted 60 feet into the Mississippi River. Ten people died, and more than 50 were seriously injured. The bridge was being repaired because it was found to be structurally deficient; it needed to be reinforced. Like many bridges throughout America, the bridge was built more than 40 years ago. Traffic was much lighter then. Nowadays, cars, buses, and big trucks cross the bridge steadily, even late at night.

“I heard a terrific boom. It was like the loudest thunder I ever heard,” said one witness to the disaster. She ran out of her car to see what was happening. She saw cars falling into the river and heard people screaming. She heard the loud cracking sounds of the bridge collapsing and splashing sounds as bridge sections and vehicles hit the water. “It was horrible,” she said.

Engineers had no explanation for the collapse. They said the bridge had been inspected recently. The report said that, although it was structurally deficient, the bridge was not unsafe. Since the report did not declare the bridge unsafe, the decision was to simply reinforce it at strategic locations.

Americans were shocked that an American bridge could simply collapse. The news was all over TV, radio, and most newspapers. One newspaper investigation revealed that almost 10 percent (about 59,000) of America’s bridges were structurally deficient.

Initially, some people speculated that terrorists might have rigged a bomb to the bridge. Others noted that all the pigeon poop on the bridge’s support rails might have eroded the steel. One blogger wrote that, before he drove over another bridge in America, he would make sure that a life jacket was in the front seat next to him.