As the summer season winds down, it's appropriate to note that August marked the fifth anniversary of the tragic collapse of the 40-year-old I-35 West bridge in Minneapolis, which killed 13 motorists and injured 145. We suggested in this column the month after the tragedy ("The answer no one wanted to hear," September 2007) that maybe we finally had the answer to the question of what it would take to convince politicians that America faces an infrastructure crisis. That answer, of course, was Minneapolis.

At least, we thought we had the answer. At the time, it seemed reasonable to assume that the public outcry would force state and federal leaders to take long-overdue steps to remediate the problem of our nation's crumbling bridges. Sadly, we were wrong.

Here's what did happen: After a 15-month investigation of the I-35W bridge collapse, the National Transportation Safety Board (NTSB) reported its finding that the calamity was a one-time occurrence caused by a previously undetected engineering design error.

Not reported was the fact that Minnesota Department of Transportation officials had known of the design defect for years. According to Barry LePatner, author of Too Big to Fall: America's Failing Infrastructure and the Way Forward and a past DC Velocity Thought Leader, consulting engineering reports presented before the collapse noted the bridge's condition and recommended a repair plan that carried a price tag of $15 million—well short of the $235 million in federal funding eventually spent to replace the bridge. Obviously, acting on the recommendations before the collapse would not only have saved 13 lives, but would also have saved American taxpayers $220 million.

There may be more tragedy in the offing, LePatner warns. While the government treated the I-35W bridge collapse as a "one-off," he says, the reality is that many other bridges pose risks to the U.S. traveling public. He points out that as recently as Sept. 8, 2011, inspectors closed the I-64 Sherman Minton Bridge carrying six lanes of traffic across the Ohio River between Louisville, Ky., and New Albany, Ind. This bridge, like the I-35W bridge, had been rated structurally deficient. It, too, would have collapsed had serious cracks in the bridge not been discovered in time to avoid further tragedy.

The troubling fact is, in the five years that have passed since the I-35W bridge collapse, little has changed. Our government remains unable (or unwilling) to act to prevent future bridge failures. "Federal and state governments are hiding the true state of disrepair of America's infrastructure," says LePatner, "I, along with many other infrastructure leaders in the U.S., thought the I-35W collapse would be a wake-up call to the nation's leaders. But it quickly became clear that the policymakers and government agencies in charge of infrastructure were content to sweep it under the rug and move on."

In the meantime, the nation's bridges continue to deteriorate. According to a report from the Federal Highway Administration (FHA), 72,000 U.S. bridges are listed as structurally deficient. In the National Bridge Inventory, a database compiled by the FHA, 18,000 bridges are listed as fracture critical, meaning a bridge's design lacks support to hold up the bridge if a single component fails. Prior to its collapse, the I-35W bridge was deemed both structurally deficient and fracture critical. There are 7,980 bridges, an average of 160 per state, still in use today that also fall into both categories.

These facts are more than scary, and they won't go away simply because they're being ignored by our state and federal governments. How many more answers like the one we got in Minneapolis in the summer of 2007 do we need before action will be taken?