Do Wider Highways Worsen Urban Traffic?


Shane Phillips, who created the above chart, thinks so:

[I]magine this scenario: you live 20 miles outside the city and want to get downtown, so you take the freeway there. The highway part of your trip used to take 30 minutes, but thanks to the new lanes it now only takes you 20 minutes. The last mile of your trip has slowed since there’s a bit more local traffic, but it only increases from three minutes to five. All told, your trip time has decreased from 33 minutes to 25–great!

Now imagine you live in the city, five miles from the city center. It used to take your bus 20 minutes to get downtown, but unfortunately as a city resident you don’t reap many benefits from the additional highway capacity. Instead, your trip is entirely on local roads, so all those extra cars coming into the city only slow you down. The trip that used to take you twenty minutes now takes thirty. The suburban visitor/commuter saved about ten minutes, and the city resident lost about ten, and all it cost was a few hundred millions dollars in construction and millions more in demolished buildings and businesses that are no longer producing revenue for the city. Money well spent, right?

(Hat tip: Angie Schmitt)