Skip to content

National Center for Sustainable Transportation Explains New Induced Travel Calculator

Confused about how building highways could end up creating more traffic congestion? This webinar can help
National Center for Sustainable Transportation Explains New Induced Travel Calculator
Adding a lane won't reduce this congestion. Photo: Wikimedia
Note: GJEL Accident Attorneys regularly sponsors coverage on Streetsblog San Francisco and Streetsblog California. Unless noted in the story, GJEL Accident Attorneys is not consulted for the content or editorial direction of the sponsored content.

The National Center for Sustainable Transportation will host a webinar later this month to discuss research that shows that building new and wider roads is at best a temporary fix for congestion. Most studies show that adding roadway capacity in congested areas ends up increasing the amount of travel over the entire network, negating any initial congestion relief.

The concept is called “induced travel.” Transportation planners, including at Caltrans and the Southern California Association of Governments, have resisted the notion, which seems to fly in the face of the logical response to congestion: widen the road, giving travelers more room. But studies show that increasing roadway capacity by ten percent leads to between six and ten percent more overall travel–and that’s on an entire network, not just the one expanded project.

New rules under the California Environmental Quality Act call for planners to measure this effect for many projects, and Caltrans is developing guidelines for how to do so. A 2013 law, S.B. 743, called for an end to using traffic congestion as a measure of the environmental impact of a project, since that took into account only the impact on driver delay, and left out other important impacts like safety and the number of new vehicle miles traveled (VMT) a project would likely produce.

It’s also simpler to measure VMT than it is to estimate delay. Planners are more accustomed to the latter, however, so researchers working with the NCST have developed a web-based calculator to make it even easier.

The webinar, on May 23, will discuss the concepts underlying induced travel and summarize current research on the topic as well as talk about how measuring VMT more closely reflects environmental impacts from travel. Then it will introduce and discuss the new VMT calculator, with input several experts including Chris Ganson from the Governor’s Office of Planning and Research.

More info is available here.

Comments Are Temporarily Disabled

Streetsblog is in the process of migrating our commenting system. During this transition, commenting is temporarily unavailable.

Once the migration is complete, you will be able to log back in and will have full access to your comment history. We appreciate your patience and look forward to having you back in the conversation soon.

More from Streetsblog California

Buffy Wicks Pushes Legislation to Cut Red Tape for Transformational Bicycle and Pedestrian Projects

April 2, 2026

The Week in Short Videos

April 2, 2026

Thursday’s Headlines

April 2, 2026

Talking Headways Podcast: Civil Rights, Civic Transport

April 2, 2026

Study: How Capping Vehicle Sizes Could Help Save the World

April 1, 2026
See all posts