Explaining Induced Traffic

Eric Jaffe at The Infrastructurist explains the non-intuitive reason why often removing freeways means less traffic.

1 minute read

June 7, 2011, 7:00 AM PDT

By Tim Halbur


Jaffe turns to a study by two economists from the University of Toronto, Gilles Duranton and Matthew Turner:

"Duranton and Turner analyzed loads of data on traffic, infrastructure, and travel behavior from metropolitan regions across the United States and found that 'vehicle-kilometers traveled increases proportionately to roadway lane kilometers for interstate highways.' For those who don't care for either academic abstracts or the metric system, the authors then parse their conclusion in pithier terms: 'roads cause traffic.' The basis for this confusing reality, write Duranton and Turner, is a three-pronged 'fundamental law of highway congestion' that explains why road construction can never keep pace with road congestion..."

Monday, June 6, 2011 in The Infrastructurist

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