The U.S. economy is a $20.5 trillion behemoth — and the nation’s infrastructure is the scaffolding upon which it depends. In many parts of the country, however, years of neglect have left critical transportation infrastructure in a state of serious, often dangerous, disrepair.

The effects of deteriorating infrastructure range in severity, from potholes adding unnecessary wear-and-tear to personal vehicles to catastrophic failures, like the I-35 bridge collapse that killed 13 people in Minneapolis in 2007. According to some estimates, delays due to roadway congestion — which are often caused by inadequate infrastructure — take a more than $120 billion toll on the economy every year.

Though the U.S. economy has grown at a steady pace over the past century, infrastructure spending has not kept up. Federal, state, and local governments invested the equivalent of 4.2% of GDP in infrastructure projects in the late 1930s, according to a report published by Congressional Research Service, the policy research arm of the U.S. Congress. As of 2016, infrastructure spending totaled just 1.5% of GDP.

Today, state and local spending account for the vast majority of infrastructure investment, and some states are doing a better job than others at maintaining roads and bridges. Using data from the Federal Highway Administration, 24/7 Wall St. reviewed the share of bridges that are structurally deficient and the share of roadway that is unserviceable to identify the states that are falling apart. 

While well-maintained roads and bridges can go a long way in improving safety conditions for motorists and passengers, they are only a small part of the equation — and the states with the worst roads are not necessarily the same as the states with the most dangerous roads. 

Additionally, though road maintenance and repair is funded largely through taxes on the sale of gasoline, high gas taxes do not necessarily translate to better road conditions. Of the 10 states with the smallest share of roadway in poor condition, Florida is the only one to also rank among the states with the highest gas taxes.

Click here to see the states that are falling apart
Click here to read our methodology