The bridge that collapsed May 23 on Interstate 5 north of Seattle had been struck by a truck hauling an oversize load, authorities said.
"The size of the load he was carrying appeared to create a problem, causing him to strike the bridge," Washington State Patrol Chief John Batiste said, according to Reuters.
Just two days before the collapse, the Seattle section of the American Society of Civil Engineers said the state's transportation infrastructure had "significant needs."
"Bridges were awarded a C-, in part due to the nearly 400 structurally deficient bridges in Washington State," it said, adding that "36 percent of Washington's bridges are past their design life of 50 years."
State Secretary of Transportation Lynn Peterson told reporters the bridge (at left) near Mount Vernon, Wash., was built in 1955. It was not among the more than 150 spans the state Department of Transportation listed as "structurally deficient" in 2011.
That was the year the American Society of Civil Engineers rated the nation's overall infrastructure a "D," with bridges receiving a "C." Of the country's nearly 600,000 bridges, 11.5 percent were rated "structurally deficient," according to Federal Highway Administration figures that year. Despite billions of dollars in annual federal, state and local funds for bridge maintenance, it was estimated that nearly $71 billion was needed to address the backlog of work needed.
Click ahead to see the states with the highest percentage of structurally deficient bridges from that 2011 report card. Washington state was the sixth-best among the 50 states and the District of Columbia that year.
Posted: 3 Nov. 2011 and updated 24 May 2013