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> If you have more cars traversing the same road with the same commute time, you have increased throughput Yes and then more cars appear. > Improving their qu

> If you have more cars traversing the same road with the same commute time, you have increased throughput Yes and then more cars appear. > Improving their quality of life while holding the quality of life of current drivers constant is a good thing. Sure absolutely people need to go places and we need to get them there. However we have neglected to consider the negative externalities of induced demand and the quality of life of everyone else who isn't a car driver. The geometric realities are such that induced demand can only be satisfied by growing the size of the road network. This has incredible costs and significant negative impacts on the community and environment. There are other alternatives that achieve the same goals. While there may be "efficiencies" to be found they cannot make up for the fixed dominant variables, the geometric reality of ever increasing SUV size, and fixed road sizes. As soon as any efficiencies open up free road space the amount of cars will simply increase, quickly closing that free road space again. So this doesn't mean that efficiencies can't be found, it just means that we need to understand the limits of efficiencies and we should not expect this to be a core solution to our traffic problems or as a key part of our broader transportation strategy.

jjk166 2y ago
> Yes and then more cars appear. This is after those cars appeared. > The geometric realities are such that induced demand can only be satisfied by growing the size of the road network. We are explicitly referring to increasing the capacity of the road network without growing its size. > s soon as any efficiencies open up free road space the amount of cars will simply increase, quickly closing that free road space again. Again, we're not looking to increase free road space, the additional cars filling that space are the benefit. There is some absolute limit on throughput where the road is completely packed full of cars all moving at maximum speed, and the only way to further increase throughput is expansion. But most road networks are no where near that limit. When you are in bumper to bumper traffic on a 60 mph highway moving at 5 mph, that road is carrying about 1/12th or 8% of its maximum capacity. That's an immense opportunity for improvement.

jjk166 2y ago

> Yes and then more cars appear. This is after those cars appeared. > The geometric realities are such that induced demand can only be satisfied by growing the size of the road network. We are explicitly referring to increasing the capacity of the road network without growing its size. > s soon as any efficiencies open up free road space the amount of cars will simply increase, quickly closing that free road space again. Again, we're not looking to increase free road space, the additional cars filling that space are the benefit. There is some absolute limit on throughput where the road is completely packed full of cars all moving at maximum speed, and the only way to further increase throughput is expansion. But most road networks are no where near that limit. When you are in bumper to bumper traffic on a 60 mph highway moving at 5 mph, that road is carrying about 1/12th or 8% of its maximum capacity. That's an immense opportunity for improvement.