One of the first things I learned in a transportation policy class was that a road improvement didn't function in isolation.  Ceteris paribus, an improved road would allow the traffic currently using it to move more smoothly (doesn't matter whether its filling potholes or a new surface or more lanes or timed traffic lights).  But a good economist learns to think about consequences beyond the immediate, which, in the transportation community come under the rubric of diverted traffic (travellers who were avoiding the unimproved road who switch) and generated traffic (non-travellers who travel because it's less burdensome.)  Apparently, this Strong Towns post suggests, the infrastructure gurus are still short of enlightenment.  "With a growing body of research showing that building more roads and more lanes just encourages more traffic, officials are starting to pay attention to induced demand."  There's more detail at the post.
The increased awareness of induced demand is a very encouraging sign. This growing acknowledgement is a key component in changing the conversation. Once we admit that building more highway capacity isn’t a real solution to congestion, we can talk about things that can actually work such as congestion pricing or building strong neighborhoods and cities that do not require such a heavy reliance on congested freeways in the first place.
These ideas are so elementary I'm surprised the wizards of smart haven't grasped them.

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