FALLING BRIDGES:
THE NATION DOESN'T FACE A CRISIS

John R. Lott, Jr. and Maxim C. Lott*

CONGRESS this week held the first nationwide hearings in the wake of the deadly Minnesota bridge collapse, and most Americans seem to think we need to spend much more to fix what The New York Times calls our "crumbling bridge system." Even in advance of this week’s hearings on the issue, House Transportation Committee Chairman Rep. James Oberstar (D-MN) said: "If you are not prepared to invest an additional five cents in bridge reconstruction and road reconstruction, God help you."

In fact, our nation’s bridge system is far from crumbling — the number deemed "structurally deficient" has fallen every year since 1990, dropping by a total of almost 50 percent.

And fewer bridges are being listed as deficient for a simple reason: Real spending on maintenance is higher now than in any previous decade.

The I-35W bridge collapse was a heartrending tragedy, but emotions shouldn’t drown out reality in the debate about what to do.

Much reporting has focused on loaded terms such as "structurally deficient" bridges, with papers across the country publishing lists of all such bridges in their area. But the term simply flags a need for regular inspections and repairs or upgrades. As the United States Department of Transportation notes in its 2006 report of bridge conditions, "The fact that a bridge is ‘deficient’ does not immediately imply that it is likely to collapse or that it is unsafe."

By any measure, even "structurally deficient" bridges" are extremely safe.

The most comprehensive database of U.S. bridge collapses comes from the New York State Department of Transportation. Of the 1,500 U.S. bridge collapses from 1966 to 2005, some 400 were the result of collisions, overloading or fires — problems maintenance is unlikely to prevent.

The New York DOT estimates that fewer than 1,100 collapses were caused by poor construction, materials, age, wear or other "miscellaneous" factors. In fact, 80 percent of those collapses were caused by "scouring" — the removal of sediment from the water around the bridge’s pillars.

Those 1,100 collapses work out to 25 a year. Since the United States holds nearly 600,000 bridges; in the United States, the odds of any given bridge falling are only about one 240th of 1 percent. (Even if the collapsed bridges were all among the 72,264 deemed "structurally deficient," the odds rise only to less than a 30th of 1 percent.)

Every disaster brings a rush to judgment and a desire to pour money into the problem. Now New York’s Sens. Charles Schumer and Hillary Clinton are both calling for drastic increases in spending on bridge maintenance.

It would be nice if politicians could for once take a step back and carefully look at where spending more actually makes sense.

*John Lott is a senior research scientist at the University of Maryland; his latest book is "Freedomnomics." Maxim Lott is a student at the College of William & Mary.