Traffic Congestion2017-10-24T11:02:30-07:00

Traffic Congestion: A Blessing in Disguise?

A typical opening to traffic congestion stories reads something like:

“Traffic congestion continues to exact a huge toll on our region’s economic vitality and quality of life. The average driver loses X hours a year to traffic, at a total cost to the economy of Y. Despite promises that project A and increased funding for B would reduce traffic, congestion seems to be getting worse.”  

Here at the UCLA Institute of Transportation Studies we grapple with the complexity of traffic congestion on a regular basis, and we think journalists would relish going deeper into this issue. On that note, we offer three core ideas to keep in mind when covering congestion:

Idea #1: We are stuck in traffic because the road is free.

The things we don’t charge for are the things we run out of. Both the car and the gas we put into it are not free, and that price plays the key role in why we don’t run out of cars or gas. But since space on roads is free, we regularly run out of it.

This lack of an adequate pricing mechanism isn’t just a clever frame for economists that has little bearing on the complicated real world. Precisely the opposite is true: pricing is the only concept worth grasping in order to understand traffic congestion.

Now, it might seem like basic fairness comes into play here- after all, roads are public space and it seems only right that all people should have equal access. But the very equality of access is what leads to overuse and eventual degradation of the road’s usefulness. When we make the choice not to create the kind of market for roads that would prevent overuse and allow for a higher degree of mobility, we are effectively choosing traffic over mobility as a preferred policy outcome.    

Road pricing in the form of tolls has recently gained momentum in several places, including Los Angeles. Since the unpredictability of traffic is one of the most stressful parts of congestion, the feature that makes HOT lanes most attractive to all drivers is the consistent availability of a swift travel lane as an option. HOT lanes are often tarred as “Lexus lanes’ for the well-off, but research on toll lane equity reveals little evidence that HOT lanes harm low-income drivers– the low-income food service worker late for a child’s school play also appreciates the “emergency option” feature of HOT lanes.

Idea #2: In the absence of pricing, the economy plays a larger role in congestion than other factors.

Traffic is often cast as a drag on the economy, but congestion would be more accurately described as an expression of the economy: as the economy improves, more people drive to work, more people buy cars and gas, and we see an increase in travel to all kinds of places. When the economy falters, people travel less because they cannot afford to do everything they were doing before. Ask Youngstown, Flint, or Reno: the only thing worse than terrible traffic congestion is none at all.

Additionally, while it appears that traffic congestion exerts a profoundly negative influence on our ability to move around the region, this again becomes a matter of perspective. Some people are infuriated by traffic as the economy improves, but other people are happy to be driving (in traffic) to a new job or making trips to stores for purchases they couldn’t previously afford. Most costs of congestion also usually fail to account for the much wider array of economic and social opportunities on offer in congested cities. If a company needs access to a top-notch music producer or a person seeks a date with a lawyer who likes cats and jazz music, they can find more options more quickly in a crowded city, even one that is congested.

Idea #3: Attempts to relieve congestion without addressing pricing are bound to fail.

Traffic congestion persists despite expensive projects such as adding new lanes on freeways and expanding rail transit systems. The expectation that these efforts will relieve congestion mistakenly assumes that the current amount of traffic represents the finite amount of driving we would like to do on our roads.

For an example, we can look closer at the number of drivers on the 405 freeway at 6 pm on an average weekday. These drivers are only a portion of the people who would like to drive on that road at that time of day. Another significant category of would-be “405 at 6 pm” drivers can be classified into three sub-groups: (a) drivers currently traveling earlier or later on the 405 to avoid congestion, (b) drivers using either alternate roads or alternate modes (rail, bus, bicycling) to the 405 at 6 pm, and (c) potential drivers who are not traveling at all at 6 pm despite a desire to do so. Any improvement in speeds on the 405 at 6 pm will therefore attract people from each of these three groups of travelers and congest the road again.

“Latent demand” is one of the firmest behavioral laws in the field of transportation. Any effort to increase speeds in congested cities will have only temporary success because there is so much latent demand for road space that almost any form of supply will be devoured by new drivers. This goes for public transit as well as added highway lanes: when the BART train opened a new passage between Oakland and San Francisco in the Bay Area, car congestion on the Bay Bridge briefly improved as people flocked to the train. But within months traffic congestion on the bridge was back to previous levels.

Final Thoughts:

Each of these three ideas is worth keeping in mind when the next report is issued about the extraordinary time and money Americans lose every year due to traffic congestion. Congestion was a problem in ancient Rome, and it was a problem in US cities long before cars were even invented. There are many untold behavioral stories lurking within the travel landscape, and they go far beyond who might start taking a new train or whose commute has become an even lengthier burden. Figuring out how to tell the story of pricing might be the biggest scoop of them all.

UCLA Lewis Center Contacts:

Brian Taylor, Director of the Lewis Center and the UCLA Institute of Transportation Studies

Martin Wachs, Professor of Urban Planning

Donald Shoup, Professor of Urban Planning

Michael Manville, Assistant Professor of Urban Planning

For reporters on deadline:

Will Livesley-O’Neill, Communications Manager
424-625-8468 /

Additional Resources:

There’s only one way to fix L.A.’s traffic, and it isn’t Elon Musk’s tunnels. We need tolls — lots of them

Traffic Congestion is Counter-Intuitive, and Fixable

Congested Development: A Study of Traffic Delays, Access and Economic Activity in Metropolitan Los Angeles

Rethinking Traffic Congestion

Moving Los Angeles: Short-Term Policy Options for Improving Transportation

Reducing Traffic Congestion and Improving Travel Options in Los Angeles

The Political Calculus of Congestion-Pricing

Just Road Pricing