Questions emerge about safety of U.S. bridges

? In a strategic plan laid out in 1998, the Federal Highway Administration set a 10-year goal of shoring up the nation’s nearly 600,000 federally funded bridges so that fewer than 20 percent would be classified as deficient.

But Wednesday’s stunning rush-hour collapse of a 600-foot bridge span along Interstate Highway 35W in Minneapolis served as a reminder that the vision fell short: More than one in four of those bridges are still rated “structurally deficient” or “functionally obsolete.”

“We have a national bridge problem,” said Rep. James Oberstar, D-Minn., chairman of the House Transportation and Infrastructure Committee. He said that 79,523 federally funded bridges are rated “functionally obsolete,” meaning they need replacing.

The tragedy also heightened attention on bridge-inspection standards, which already had drawn scrutiny. Last year, a Transportation Department audit of 43 bridges in Massachusetts, New York and Texas found that bridge inspectors routinely miscalculated the load capacity of structurally deficient bridges, posting weight limits that allowed vehicles exceeding the safety threshold or failing to post limits at all.