Induced Demand is a term that comes up frequently in discussions about freeway projects. Simply put, it’s the idea that when you add freeway capacity, it attracts new users who previously hadn’t used the freeway (or used it at different times) and as a result congestion quickly returns to previous or even higher levels.
Rather than provide a detailed discussion of the mechanisms that drive (pun intended) this, we thought we’d point you to some existing videos that do the job nicely and only take a few minutes to watch.
The first video is a straight up description of why induced demand happens, the second is a more satirical look at how this plays out in the political space. Either way, enjoy!
We also hear the term “latent demand”. That’s a slightly different assertion, which is that there are folks who really want to or need to use a road, but don’t because it’s too congested. We think this is a difference without a distinction. The core principal is that more road capacity leads to more driving which leads to increases in greenhouse gases and air toxics production.
Our core point is that we need stop orienting our transportation investments on accommodating an essential endless desire for more road capacity that DOTs are fixated on and instead design a transportation system that meets all the needs of our society including access, mobility, equity, climate, environment and livability.