Shutterstock

Researchers in Denmark found that municipalities underestimate the economic and environmental impact of new roads.

Here's an all-too-common phenomenon - a city decides to build or expand a road to decrease traffic. The road is built. Traffic increases instead. This is called induced demand, whereby drivers avoiding the road because of congestion jump back onto it once the project is finished.

But municipalities often fail to properly account for this phenomenon, according to a new study of out Denmark.

The researchers found that "the traffic-generating effects of road capacity expansion are still often neglected in transport modelling." This can lead cities to make mistakes when assessing the environmental impact and economic vitality of proposed road projects.

As Streetsblog writes:

According to the study, completed by researchers at the Institute of Transport Economics and a Danish university, this leads to skewed cost-benefit analyses that call for new highways and road widenings of dubious benefit to the public.

Researchers reported that perceived time savings make up the largest portion — sometimes 85 percent — of the economic benefits assigned to prospective highway projects. But an unanticipated boost in traffic volume can turn many projects that would theoretically pass analytical muster into economic losers. Unless transportation agencies are carefully accounting for these effects, however, many of these projects get built anyway.

Photo credit: chaoss /Shutterstock

About the Author

Most Popular

  1. a photo collage of 2020 presidential candidates.
    Equity

    Will Housing Swing the 2020 Election?

    Among Democratic candidates for president, the politics of America’s housing affordability crisis are getting complicated. Just wait until Trump barges in.

  2. A person tapes an eviction notice to the door of an apartment.
    Equity

    Why Landlords File for Eviction (Hint: It’s Usually Not to Evict)

    Most of the time, a new study finds, landlords file for eviction because it tilts the power dynamic in their favor—not because they want to eject their tenants.

  3. A photo of an abandoned building in Newark, New Jersey.
    Equity

    The 10 Cities Getting a Philanthropic Boost for Economic Mobility

    An initiative funded by Bloomberg Philanthropies, the Bill & Melinda Gates Foundation, and Ballmer Group focuses on building “pipelines of opportunity.”

  4. A cat lays flat on a bench at a park on the outskirts of Tokyo.
    Life

    Why Don't Americans Use Their Parks at Night?

    Most cities aren’t fond of letting people use parks after dark. But there are good lifestyle, environmental, and safety reasons to reconsider.

  5. At an NBA game, a player attempts to block a player from the rival team who has the ball.
    Life

    NBA Free Agents Cluster in Superstar Cities, Too

    Pro basketball follows the winner-take-all geography of America as a whole, with free agents gravitating to New York, L.A., and other big cities.

×