Skip to main content

Why do we sit in traffic jams so frequently

Posted: March 6, 2011 - 7:21PM
Author: Don Bain
The simple answer to why drivers sit in traffic jams so frequently is we all want to use the same piece of interstate at the same time causing the demand for space on the freeway to exceed the capacity. Given this, there are forces at work that can be explained by human nature and an analogy drawing upon particle motion.


In years past, the phenomenon was easy to understand – everyone worked in the city and lived in the suburbs and since we all worked the same hours, everyone ended up on the freeway going the same way at the same time daily.

In those days, the savvy commuter avoided the crowds by simply living in the city and working in the suburbs, thus avoiding the throng going the other way.

Nowadays, it’s not that simple. People live all over and work all over, not to mention all different shifts and hours. You’re likely to encounter crowds over a much greater area of your city and a wider range of times.

The folks at the Car Insurance Guide have released a scientific study of traffic jams revealing fascinating insights into not only traffic patterns but perhaps human nature itself.

Though their findings will be shallow comfort when your sitting behind a sea of red tail lights, it might help to have someone to blame for your condition – as long as it isn’t you.

Half of all traffic slowdowns and jam-ups occur from periodically recurring traffic patterns – everyone going the same way at the same time. The other half are caused by traffic incidents, construction zones and weather related events.

The further analysis is where it resembles wave or particle physics.

In something called The Butterfly Effect a driver makes some simple maneuver, such as a lane change, surprising another driver who taps their brakes, slowing slightly. Nearby drivers, seeing a flash of red in their periphery, tap their brakes causing a ripple to move through the flow.

Once created, this ripple effect continues to move through traffic until the numbers on the freeway dissipate.

Another theory simply states that because the use of thoroughfares is free, people use them as much as they like, causing congestion resulting from either poor planning or some form of herd behavior.

Solutions are said to include ramp signals, which are already in widespread use yet the problem persists.

Perhaps more effective would be bus lanes, which would keep their erratic movement from affecting through traffic.

Doubtless the most effective solution is highways with signal reversible lanes, so the number of lanes going a particular direction could be increased at specific times to handle the load.

This seems to be the best solution, but the recent number of incidents involving drunken drivers going the wrong direction on clearly divided highways has a sobering effect on such thinking.

If there are drivers on the road so incapable of following clearly marked directional indicators – who don’t even notice everyone else going the other way – this solution could well be a recipe for modern disaster.

The best solution is not really practical for most of us – it involves living closer to where you work and shop. Such is the world we live in.