The Myth of the Falling Bridge

Are American bridges actually falling? Is the U.S. underinvested in infrastructure? 

There's more than a touch of Chicken Little in common arguments for more infrastructure spending. "The bridges are falling, the bridges are falling!"

Every four years, the American Society of Civil Engineers issues the U.S. an infrastructure "report card." And, just as predictably, it says that U.S. infrastructure is decrepit and needs expensive new investments. The latest one, released last month, gave the nation a D+ grade and recommended an extra $1.6 trillion in spending by 2020.

Are American bridges actually falling, though? Is the U.S. underinvested in infrastructure?

Maybe it's going too far to say, "The U.S. is doing just fine, thank you very much." The nation would benefit from reordering its infrastructure priorities -- away from new highways, for example, where we are already overbuilt and usage is falling for the first extended period on record. And we'd do well to take advantage of low interest rates and idle construction resources to knock out all of our future infrastructure needs.

But the idea that the U.S. has an infrastructure crisis? No. A broad, permanent increase in spending is unwarranted.

How much does the U.S. spend on infrastructure compared to the rest of the world?

It's in the middle of the pack. Between 2001 and 2011, annual public investment averaged 3.3 percent of gross domestic product, according to the Organization for Economic Cooperation and Development. The average OECD nation spent 3 percent of GDP over the same period.

A 2011 study by Marco Percoco, a professor at Bocconi University in Italy, shows that U.S. public investment has tracked the OECD average since at least 1970. Developed nations invest between 2 percent and 3.5 percent of GDP. The U.S. is about where it should be -- close to peer nations such as Canada, Germany and Australia. Nations that spend substantially more tend to be in a phase of catch-up growth, such as South Korea and Poland.

Is the U.S. reducing its infrastructure spending?

It's been pretty steady. Total public construction spending has varied between 1.7 percent and 2.3 percent of GDP for the last 20 years, according to the U.S. Census Bureau. By the Congressional Budget Office's slightly different measure, infrastructure spending has been between 2.3 percent and 3.1 percent of GDP since 1956.

Is the quality of infrastructure worsening?

Just the opposite. Believe it or not, infrastructure has improved significantly over the last two decades. In its report for 2010, the Federal Highway Administration said that 57 percent of all vehicle-miles were traveled on federal highways with ratings of "good" or higher -- according to a measure of road quality pleasingly known as the International Roughness Index. That was up from 48 percent in 2000. The percentage of roads in bad condition has also declined: In 1989 6.6 percent of rural and urban interstates were rated "poor"; now only 1.9 percent of rural interstates and 5.4 percent of urban ones earn that grade.

Despite warnings from President Barack Obama, America's bridges have never been safer. The highway administration rated 21.9 percent of its bridges "deficient" in 2009, as compared to 37.8 percent in 1989. And contrary to Obama's implication, the word "deficient" does not mean unsafe, at least as the highway administration uses it. A bridge is "deficient" when it would benefit from expansion and renovation in line with usage.

Traffic congestion has diminished. In 1989, 52.6 percent of urban interstates were rated "congested" according to a comparison of peak volume to planned capacity. In 2009, the figure was 26.3 percent.

Now, advocates for more infrastructure spending might believe that no road should have a pothole or ever be congested. But there's a big pothole in that reasoning, called trade-offs. Timing aside, America seems to be spending about the right amount on infrastructure, just as it always has, just like most other developed nations.

This column does not necessarily reflect the opinion of Bloomberg View's editorial board or Bloomberg LP, its owners and investors.