Induced traffic

By: J. David Chapman/February 3, 2022

When I ran for city council, the No. 1 issue was traffic. As I approach my last year in office, surveys indicate the No. 1 issue is still traffic. Glad I didn’t propose to “fix” the traffic as a campaign promise.

My experience in urban planning has taught me that we will never fix the congestion in our roads because we favor a model of analysis that prioritizes “mobility,” which increases the speed for moving vehicles, and the time that is saved as a result. While this may make sense on an intuitive level, it is a problematic measure today.

Making it easier to move cars around has led to an overemphasis on road construction that doesn’t seem to be working. Our research of 100 cities studied indicate that since 1994 congestion has gotten worse in all but one city when measured by their Travel Time Index. During that time, 92 of these 100 cities saw an increase in the amount of roadway miles per capita. Population in those cities outpaced roadway construction only slightly and should not have had an impact on the congestion.

What we are witnessing in these cities is called induced traffic – if you build it, they will come. More road-building to try to move vehicles faster often makes traffic worse. So, what should we be doing? Maybe we should try to consider the ends and not the means. Concentrate not on movement or mobility of vehicles, but, rather, the accessibility the system provides for people; whether it is getting to school, work, church, shopping, or recreation. I also would propose to consider whether traffic and congestion is really an issue.

Some argue that traffic is a good sign for cities and integral to how modern societies function. It is seen as an indicator of prosperity because it shows success in the economy. The increase in traffic may cause people to live closer to their jobs or compel businesses to locate closer to their workforce. Some may even, heaven-forbid, choose to take public transportation. It could slow drivers’ speed and actually make roads safer.

So, as a politician, if I can’t fix traffic and congestion, maybe I can convince my constituents that it isn’t a problem or even persuade them that it is a positive. I am kidding, but what I am serious about is that we need a new approach.

J. David Chapman is a professor of finance and real estate at the University of Central Oklahoma (jchapman7@uco.edu).