It’s Part II of our two-part series on traffic congestion! This time: why adding more lanes doesn’t make congestion go away.

Framing traffic congestion as primarily a “street capacity” problem has led practitioners to seek solutions by adding more lanes and miles of streets and roads. This has the unintended (but predictable) consequence of generating more traffic. This phenomenon is exceedingly well known but continually ignored among the professionals who can do anything about it.

Let’s talk about it.

Links:

Want to learn more on this episode’s topic? Here’s just a short list of interesting resources:

• Traffic Jam? Blame 'Induced Demand.' - Bloomberg
• Transportation For America More highways, more driving, more emissions: Explaining "induced demand" - Transportation For America
• The Fundamental, Global Law of Road Congestion (from City Observatory)
• Reducing Traffic or Inducing It?
• What's Up With That: Building Bigger Roads Actually Makes Traffic Worse | WIRED
• Induced Demand: An Axiom of Biology — Human Transit
• Questioning Congestion Costs | City Observatory
• Induced demand - Wikipedia
• Reducing congestion: Katy didn't | City Observatory
• Reduced demand is just as important as induced demand | CNU
• The Problem with HOV Lanes
• Opinion: Filth, Automobiles, and Our Misguided Obsession With Traffic
• Calculating induced demand at the Rose Quarter | City Observatory
• Generated Traffic and Induced Travel – VPTI (PDF)
• Your Navigation App Is Making Traffic Unmanageable | Institute of Transportation Studies
• SHIFT Calculator
• Book: Walkable City by Jeff Speck (public library)

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