New research published by the National Bureau of Economic Research measuring the social cost of damaged roads buttresses the case for prioritization of highway repairs.
“The rougher the roads are, there are substantial costs in terms of higher vehicle operating costs, longer travel times and less traffic safety,” says Margaret Bock, professor of economics at Goucher College. “Our estimates are a lot larger than previous estimates. We really need to be investing in fixing the roads.”
Bock’s paper, written with Alexander Cardazzi and Brad Humphreys, finds that even modest road damage slows average vehicle speeds by 11 percent and increases the likelihood of crashes. (Although slower travel makes individual car crashes less likely and less deadly, the researchers looked at aggregate speeds over the course of a month, and they think that explains the disparity; it also looks at highways, not local roads with pedestrians.)
The trio of researchers studied California’s highway system, because it is one of the largest and most geographically diverse in the nation. The state contains almost 400,000 road miles across a variety of climates, the second most expansive system in the nation (behind only Texas).
California already spends an astronomical amount on its highways. In 2018-2019, the state’s Department of Transportation increased spending on road maintenance from $421 million to $576 million, and road rehabilitation from $424 million to $994 million. (The larger number includes additional costs beyond pavement, like guardrail installation and repair.)
Nationally, in 2017, highway maintenance cost the country $51.4 billion. More than two times that amount was spent the same year on the construction of new roads.
In their paper, the authors argue that the wear and tear on our highway system has greater costs than were previously understood, “implying a need for more transportation infrastructure investment, especially for road maintenance.”
Do the authors have any faith that the infrastructure bill, and the way state governments put its prospective bounty to use, will get the balance right?
“Its really great Congress is proposing to shell out a lot of money for infrastructure repair,” says Bock. “But some more of the money that’s going towards new road construction could be devoted to repair. Based on our paper, a lot of the costs associated with pavement damage have been underestimated.”
David King, a professor of urban planning at Arizona State University, agrees with the conclusion that the country should have a fix-it-first mentality when it comes to highway spending. The infrastructure bill, however, still pushes a substantial amount of money to new road construction.
But the need for aggressive spending on new highways is not clear. King says that in many parts of the country, roadways are being abandoned or returned to gravel. The principle of induced demand, meanwhile, has proven that expanding heavily used roadways will not affect traffic in the medium term. If you build it, drivers will fill it.
“Road expansion is something that we do because there’s free money to do it,” says King. “There are forward-looking ways that cities, regions and states should be thinking about infrastructure spending [as opposed to policy] organized around road building to make sure that we’re set up for the 1980 economy.”
Cardazzi and Bock’s paper notes in passing that “efficient user fees” should reflect the actual costs of transportation infrastructure use. But in much of America, the upfront costs of roads are free, with tolls relatively scarce and congestion pricing non-existent. That means drivers and non-drivers alike pay on the back end in the form of taxes and publicly supported subsidies.
King says that there are myriad ways that user fees could be implemented. Much of the heaviest road damage is caused by large trucks, so a different fee structure for commercial and passenger vehicles makes a lot of sense.
“There’s research looking at the major determinants of road deterioration and trucks are the main drivers of this,” says Alexander Cardazzi, Bock’s co-author, who teaches economics at West Virginia University. “Maybe truck tolls should be more expensive, because those are the things that are really damaging the pavement.”
The oft-proposed vehicle miles traveled fee could target its sanctions to specifically make it more expensive for big rigs to drive on local roads, where they cause worse damage, as opposed to freeways. Congestion pricing or more highway tolls would also better reflect the actual cost of keeping roadways in good repair, support transit options, and incentivize people to drive less.
Although driving has become a cornerstone of American life, the negative externalities of a mass motorized nation are immense. In the U.S., transportation is the largest source of greenhouse emissions, pedestrian deaths have been rising and the downtowns of many cities and towns have been hollowed out by sprawling suburban development (which is also greenhouse gas intensive).
Because automobiles are a largely unexamined part of everyday life, the infrastructure that supports them is unthinkingly extended and changes are met with political backlash that few politicians wish to face. As a result, vehicle miles traveled taxes and other user fees (like congestion charges) are largely non-starters.
But an expert can dream.
“User fees are a wonderful way to not just raise revenue, but to reflect the overall cost to society of the travel choices people are making,” says King. “If we could really get a system of user fees, that should also influence how [policymakers] spend their money and how their priorities are set within the funding and within the infrastructure bill itself.”
