Ray Delahanty | CityNerd
4 HN mentions · mentioned in 3 months, 2022–2024
12:05 · 100K views · Dec 16, 2021
CityNerd explains why traffic congestion grows nonlinearly as more cars use a road network, and why adding road capacity tends not to fix it. It covers the consequences for drivers, bus riders, cyclists and pedestrians, and discusses alternatives such as true bus rapid transit.
HN commenters cite it when arguing that congestion is an exponential, feedback-driven problem so widening roads or removing a few cars behaves counterintuitively.
4 comments from Hacker News
This is a straw man argument, where you’re using a worst-case scenario for buses. A quick rail line could get you to the office in under an hour, and would beat traffic if it was designed well. Hell, buses ought to skip traffic via dedicated lanes since they’re carrying so many more people than a car. But it’s important to note that only takes 2-3 hours because public transit doesn’t get the investment it needs to be good . And even when cars do get an extreme amount of investment, it still takes you an hour to go 25 miles. It should be clear at this point that driving is not a scalable, general solution for quick, effective transit in areas with lots of people. The pretty simple reason is that traffic congestion is an exponential problem ( this video ). As a result, investing in car infrastructure is actually not a good way to improve your commute time. It may seem backwards, but since more car infrastructure encourages more drivers, and since more drivers increase congestion at an exponential rate , more car infrastructure tends to (at the best case) not improve the situation at all. This is why people like myself really try to push for investment in other forms of transit. If you have multiple, high-quality transit options, some people will pick the train, some will pick a bike, and others will pick a car. If biking and taking the train or bus is good enough that it gets a few drivers off the road, that makes the experience significantly better for you, as we are now decreasi
Traffic congestion increases nonlinearly[1]. i.e. the 10th car on a road has a smaller effect than the 100th car on the road. Accordingly, the cost of increasing a bus' size and decreasing its speed pales in comparison to the value derived by removing 5-20 cars from the road. this video
ah yes, "traffic enforcement fixes traffic" That's why there exists no traffic in all of the places with traffic police. It's not at all like it's a positive feedback loop where one person messing up parking causes downstream effects for the rest of the day... this video
Here's a video on the topic: ("Why Traffic Congestion Grows Exponentially, Why It Matters, and What To Do About It") this video