A recent paper in Nature Climate Change says climate change is costing the U.S. billions of dollars in unnecessary road repairs each year. Most road miles in the U.S. are in rural areas, meaning states, counties and small towns are making repairs that some of them can ill afford.
The problem is old data. Engineers consult weather models to see what kind of pavement can best withstand the local climate. But the temperature data for those models runs from 1964 to 1995, and local weather is often different now.
"Using data from the Bureau of Transportation Statistics, Shane Underwood of Arizona State University and his colleagues show that road engineers have selected materials inappropriate for current temperatures 35 percent of the time over the past two decades," David Trilling reports for Journalist's Resource, a service of the Shorenstein Center at Harvard University. Other findings from the study:
Failing to adapt to warmer temperatures is adding three to nine percent to the cost of building and maintaining a road over 30 years.
The authors use two models of predicted warmer temperatures, which suggest between $13.6 and $35.8 billion in extra or earlier-than-normal repairs will be required for roads being built under the current models. In the lower-temperature warming model, this translates to an annual extra cost of between $0.8 billion and $1.3 billion; in the higher-temperature warming model, it is an annual extra cost of between $0.8 billion and $2.1 billion.
A road built to last 20 years will require repairs after 14 to 17 years under these models.
In some cases, government transportation agencies are paying too much for materials to withstand cold temperatures that do not currently (and perhaps no longer) exist.
Because municipal governments in the United States work on tighter road-maintenance budgets than state and federal transportation departments, the extra financial strain will largely impact cities and towns.