Why Can't We Solve the Modern Traffic Jam?

Air pollution inside your car during rush hour may be twice as high as previously thought. B137/Wikimedia Commons

The modern plague known as traffic congestion has been driving us crazy for decades. At some point during the week, many of us are stuck in our cars, going nowhere. In addition to the in-the-car misery, the grind of gridlock raises environmental concerns, and there’s also the problem of lost productivity.

Despite all of the technological advances that make our lives easier, we’ve yet to come up with a definitive answer to the traffic congestion conundrum, and it doesn’t seem like the problem is going to get better anytime soon.

In February, drivers in Los Angeles attempted to avoid gridlock traffic by driving through a field of sand — only to get stuck there, according to Jalopink. Last year, The Star declared that traffic congestion in Toronto is just as bad as it was in cities like New York, Los Angeles and Boston. In addition, the traffic congestion along the busiest stretch of Toronto highways could add 36 minutes to a 60-minute commute, translating to an annual total of 3.2 million driver-hours in delays.

These are just two recent examples, but the issue of traffic congestion is nothing new. So how are we supposed to tackle this problem?

Causes of traffic

Many of us are quick to blame traffic congestion on other drivers. If just those few drivers ahead of us would pay closer attention, then we could breeze by and arrive at our destination with (relative) ease. But as drivers, we’re all part of the problem.

Of course, there are many factors that are out of our hands: There's not enough supply (roads) to meet demand (traffic flow, given the number of cars); there's road work, out-of-sync traffic lights and even the presence of pedestrians — though putting any blame on pedestrians isn’t the answer.

There are lots of factors we need to take into account, including that everyone behind the wheel if a vehicle is a factor.

Is it that we're all terrible drivers who have no respect for others on the road? In some cases, yes. But, a lot of it has to do with other issues — like not having the necessary reaction time needed to keep traffic flowing steadily or an inability to control the distance between cars.

Reaction time and traffic lights

How human reaction time and distance between cars play a part in traffic congestion is illustrated in a video produced by CGP Grey.

To begin with, let’s think for a moment about reaction time as it relates to traffic lights at intersections. When waiting at a light, the light turns green and all the cars begin to accelerate and move forward, but they don’t do so at the same time. The first car goes, then the second, then the third, and so on before eventually one car isn’t able to make it through the light and stops. As humans we aren’t all able to react quickly enough to accelerate simultaneously, and that means there isn’t enough time for a large number of drivers to get through a light.

Since the number of cars that can get through a traffic light is limited, there will inevitably be an instance where at least one driver gets caught in the intersection (because someone at some point didn’t react quickly enough), which creates gridlock.The more intersections there are, the more traffic lights there are, which means more opportunity for congestion.

Highways and phantom intersections

traffic jam
Traffic on interstates can quickly back up if just one vehicle slows down. Kichigin/Shutterstock

So, now let's think about highway traffic.

The main idea behind a highway is that it's supposed to keep traffic at a steady flow because no one has to stop at intersections. We already know that more intersections and more lights create more traffic, so in theory, we should all be able to hit the freeways with little interference from traffic congestion. Unfortunately, that's not how it works.

For one, there are other types of intersections as people enter or exit the highway. The number of intersections is definitely less than on a main road, but the intersections are there nonetheless.

But, even if there were no intersections, we still wouldn’t even be able to avoid traffic. This is where the idea of the phantom intersection comes into play.

To explain phantom intersections, let’s consider what would happen if a chicken were to cross a one-lane highway.

In this case, drivers have been traveling smoothly along the highway with no intersections to impede the flow of traffic, and then a chicken decides to cross the road. The driver who sees the chicken must momentarily slow down to avoid hitting the chicken, which ultimately causes every other driver to have to slow down as well. It may not happen immediately, but at some point, a driver is going to have to come to a complete stop. Given the fact that humans don’t have the greatest reaction time, every driver is going to be breaking and slowing down at different speeds, which means there's no longer steady traffic flow.

Even though the chicken crossed the road a long time ago, it created a phantom intersection because everyone had to slow down as if an intersection were present. It’d be nice to think that phantom intersections are only created by chickens crossing over a one-lane highway, but multilane highways with no chickens are just as vulnerable (if not more so) to phantom intersections.

When drivers cross highway lanes too quickly, that causes the drivers behind to have to react and then slow down to avoid a collision. Drivers move through multiple lanes all the time (in every direction), which means all of us are constantly slowing down and speeding up, which creates unsteady traffic flow.

The best way to remedy the traffic caused by phantom intersections is for every driver to stay equidistant between the car in front of them and the car behind them. But, that’s pretty much impossible to do.

Self-driving cars

Google self-driving car
A Lexus RX450h retrofitted by Google for its driverless car fleet. Steve Jurvetson/Wikimedia Commons

This is one reason why many people are proponents of self-driving cars. Drivers aren’t able (and most likely not willing) to consistently monitor the distance between themselves and other cars, but self-driving cars can easily monitor that distance. Not only can self-driving cars tackle the distance issue, but they’re able to react much more quickly than humans to changes in traffic. You may question if self-driving cars are the best way to make sure human error doesn't play a role in traffic, but that's one of the big reasons people advocate for self-driving cars.

Self-driving cars seem like a viable option for reducing traffic, but there's much more we can do. Since we are nowhere near a consensus at this point, it's worth exploring some of these options.

Adding more lanes

Since one major traffic cause is simply that there are too many cars on the road, adding more roads and widening roads doesn't seem like such a bad idea. While in some cases it probably helps, adding more lanes can sometimes be ineffective, reports Phys.org.

In certain cases, when more lanes are added to a road, drivers who previously didn't use that road then begin to take it, and then you have even more traffic than before. This isn't to say that more lanes should never be added to a road, but it does show that it can create some complications — not to mention all the construction.

Roundabouts and diverging diamond interchanges

aerial view of highways
Utah State Route 201 and the Utah State Route 154 form a diverging diamond interchange. Supercarwaar/Wikimedia Commons

Roundabouts have been shown to improve steady traffic flow with little congestion, reports The Washington State Department of Transportation and The U.S. Department of Transportation Federal Highway Administration.

Roundabouts do away with the need for traffic lights at intersections, which we already know can be detrimental to a smooth traffic flow. Of course, building a roundabout requires lots of construction, and there are portions of cities where it isn't practical to build them, but it's something to consider if the location permits.

Smart technology in cities

Implementing smart technology in cities can help reduce traffic congestion, reports Geotab.

Some cities have already started to make use of Vehicle-to-Vehicle technology (V2V) and Vehicle-to-Infrastructure technology (V2I). V2V technology is essentially vehicles communicating with one another on the road, which is how self-driving cars work. V2I technology allows vehicles to send and receive information to surrounding infrastructure like traffic signals and weather alert systems. The vehicle can send information to the infrastructure and vice versa.

For example, Columbus, Ohio, is using V2I technology to create adaptive traffic signals to improve the timing of traffic lights, reports Statetech. The technology helps officials study how long cars sit at lights, and what the traffic flow is like at certain times of the day.

In Texas, utilities and public energy authorities have been using drone technology to handle certain day-to-day tasks that would normally be carried out by field workers driving bucket trucks, reports Worktruck.

The basics

Of course, there's always the most basic ways to help combat traffic. Walking or cycling instead of driving is never a bad idea; it takes cars off the roads and offers an opportunity for exercise. Also, you can try carpooling to and from work or taking advantage of public transportation. Since one major cause of traffic is the number of cars on the road, anything you can do to help limit that number is a step in the right direction.

There doesn’t seem to be any one way to fight the perennial problem of traffic congestion, but it's never a hopeless endeavor to think about solutions. And if you need some fuel to push you to reach the same conclusion, just consider a couple of our most memorable traffic jams.

Interstate 45, Texas, 2005

traffic jam I-45
Traffic backs up for miles on Interstate 45 near Galveston, Texas as people evacuated for Hurricane Rita. Ed Edahl/FEMA/Wikimedia Commons

When Hurricane Rita hit Texas in 2005, residents were asked to evacuate on Sept. 21. About 2.5 million people evacuated, which caused a 100-mile queue on Interstate 45. The congestion went on for 48 hours, leaving some drivers stranded for 24 hours. Even though the traffic jam was intense, many lives were most likely saved.

Beijing 2010

In Beijing in 2010, there was a traffic jam that stretched 62 miles and went on for 12 days. It took up to three days for some drivers to travel across the Beijing-Tibet expressways simply because there were too many cars on the road. The oddest part of the story is that a large group of trucks carrying equipment for road work played a big role in the congestion.

Bethel, New York, 1969

Bethel New York 1969
Youths and adults walk along roads choked with traffic on the way to Woodstock. Hulton Archive/Getty Images

In addition to Woodstock Music & Arts Festival featuring "three days of peace and music," it was also accompanied by a traffic jam that stretched over 20 miles. Many eventually abandoned their cars to attend the festival.