US bridges

Why Many US Bridges Are On The Verge Of Collapse

Hundreds of thousands of bridges across America do not comply with the standards they were designed for.

According to the Federal Highway Authority (FHA), there are more than 600,000 bridges in the country. More than 100,000, or 16% of them, are considered to be deficient, meaning they’re not up to the FHA standard.

Of those deficient bridges, 71,880 are considered “functionally obsolete,” which means that they don’t meet current design standards, and/or carry a level of traffic that exceeds the level it was built for.

The remaining 28,800 are considered “structurally deficient,” meaning important bridge elements have deteriorated and carrying capacity may have been reduced. The FHA says this “does not imply that a bridge is unsafe,” but adds that these bridges need significant maintenance to remain in service, and need major rehabilitation or replacement in the future.

Save our Bridges, however, an organization advocating  for infrastructure overhaul of US bridges, says there are 7,980 bridges that have been deemed structurally deficient and “fracture critical,” which the FHA defines as having at least one “steel member in tension, or with a tension element, whose failure would probably cause a portion of or the entire bridge to collapse.”

Which bridges near you are dangerous?

Using FHA information, Save our Bridges has compiled a map of all of these bridges, which includes information such as when the bridge in question was built and how many people cross it on a daily basis. The map is available as an iPhone app.

Meanwhile, look out for local efforts, such as this app from Michigan state with which users can share the locations of dangerous bridges in the state.


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Ole Skaar