Lessons in Freeway Widening

The lesson is simple: don't widen freeways if you want to reduce congestion and auto-dependence.

1 minute read

August 26, 2017, 7:00 AM PDT

By James Brasuell @CasualBrasuell


Joe Cortright offers a collection of case studies on the futility of highway widening projects.

Cortright is offering these lessons in opposition to a proposal "to spend upwards of a billion dollars on three freeway widening projects" in the region around Portland, Oregon.

According to Cortright, the idea of widening freeways to lessen congestion has been "thoroughly debunked." In fact, writes Cortright, "[e]conomists now talk about the 'Fundamental Law of Road Congestion'–each incremental increase in highway capacity generates a proportionate increase in traffic, with the effect that congestion quickly rebounds to previous levels–accompanied by more sprawl, longer trips and increased pollution."

As examples to counter the argument of Oregon's highway widening project proponents, Cortright lists Houston (specifically, the 23-lane Katy Freeway), Dallas (i.e., the decision to cancel the Trinity Parkway), Louisville (the infamous Spaghetti Junction and Ohio River Bridges Project completed earlier this year), and Rochester (which began removing the Inner Loop freeway in late 2016).

Wednesday, August 23, 2017 in City Observatory

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