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by ghobs91 2479 days ago
Road traffic is caused by two main things: congestion and bottlenecks.

Congestion is solved by properly designing cities and their transit systems so that there's an optimal ratio of car/bus/train/bike use.

Bottlenecks are solved by properly designing the road network itself so that you don't have situations where 5 lanes become 2, or highway onramps/off-ramps that are too short and cause an entire lane to be backed up by people entering and leaving.

Yes adding more lanes by itself doesn't solve the problem due to induced demand, but refusing to expand highways while simultaneously neglecting to have transit keep up with growth is even worse.

I personally think that all new housing should have a state "transit expansion" tax per unit of housing it introduces, to allow the system to keep up with growth.

2 comments

> I personally think that all new housing should have a state "transit expansion" tax per unit of housing it introduces, to allow the system to keep up with growth.

Why not just tax the transit use directly? That way you remove the complexity of determining which new housing is reducing traffic (by letting people commute less) and which housing is increasing traffic by how much.

Taxing transit use directly is called a bus ticket.

However when you provide unmetered road usage you also need to provide subsidies to persuade people to use transit, which is what transit taxes do.

There are other ways to do road pricing: odometer taxes, toll roads, even fuel taxes.
> Congestion is solved by properly designing cities and their transit systems

Redesigning a city/system won't eliminate congestion because it can form even in straight-line conditions:

https://www.youtube.com/watch?v=6ZC9h8jgSj4

It all starts when a single car slows down, causing the car behind slow further, the chain reaction continues until all traffic stops. The phenomena can be seen as waves in the video. However, breaking is not the cause of the problem because this situation wouldn't exist if individual cars were able to accelerate at the same time as those in front. The answer are smart vehicles capable of accelerating with zero reaction time.

I don't think congestion is a problem by itself as long as there are no traffic waves and no bottlenecks ahead. Just imagine congested traffic moving uniformly at high speed.