4 HN users recommended this explainer4 months2021–2023score 4.5
Years with an HN recommendation, 2007–2026
HN points to it as a clear introduction to why widening roads fails and why transit-only lanes matter.
Not Just Bikes explains the Downs-Thomson paradox using Amsterdam and Toronto: road widening doesn't fix congestion, and buses stuck in traffic make transit slow. It argues for giving transit its own priority infrastructure.
“NotJustBikes has a good introduction to it” (HN, 2022)
Please, please watch the videos I linked. Especially the Not Just Bikes channel. For example, this one [this video] can quickly explain why a transport system flooded with autonomous cars and poor public transit would make the overall system worse for everyone . There is also another video that talks about microcars for people with disability and reduced mobility: [link] No rational person can watch those videos and conclude that the best course of action to solve urban transportation requires self-driving cars. Getting FSD cars is just a rich nerd fetish which will not solve anything and likely contribute to make suburban sprawl worse.
Why autonomous cars with poor transit make the system worse
Train fans will always still take the train, and for good reason (they are a better experience in some ways), but the fundamental issue of whether we can address car traffic and congestion is about whether other forms of transit can be faster. [this video] and [link] are great overviews
Correct, The Downs-Thomson paradox [1] is a known issue in urban planning stating basically unless you improve public transportation car congestion will continue to get worse. > the equilibrium speed of car traffic on a road network is determined by the average door-to-door speed of equivalent journeys taken by public transport. NotJustBikes has a good introduction to it [2] [1] [link] [2] [this video]
The less you invest in public transportation, the more people will drive. The more people that drive, the slower traffic gets. If you just widen the road, all you do is increase the amount of cars that drive. If people can't get to where they are going via public transportation, then they are going to drive instead, increasing congestion. Would recommend watching this video on it: [this video]
Explains why road widening does not fix congestion
To reduce congestion you need to speed up and expand the slowest alternative, public transport. That is the only proven method to reduce congestion. The peak demand for car travel is way beyond the infrastructure which is possible to construct and maintain. More info: [this video]
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