Fixing City Traffic - Civil Engineering Hack


Thinking about how to fix traffic congestion during rush hour in cities. Is it possible to have a 1-way street that switches direction? If so, instead of having alternating 1-way streets, we could have groups of 3 streets leading into and out of a city. In the morning, 2 of 3 streets point toward the city for people going to work. In the evening, 2 of 3 streets point away from the city for people going home.

Other than this being potentially dangerous because of people getting confused, could this be a viable solution? It might require more self-driving cars to really work well.



I feel like that is a great idea in theory, but as you said many people would likely get very confused… but yes I think with more self-driving cars this could certainly work well, especially when there are only self-driving cars (if that ever comes, which I feel it might).

If they were clearly marked and it was announced months in advance with enough publicity then it could perhaps work, though there will undoubtedly people who don’t understand or forget etc.

Interesting thought though!



Announcements would help but I think prominent digital signs would be necessary to clearly mark the direction of a street and deter people from going down the wrong way.



I agree, but having worked with digital signage I can say that they do not do well in sunlight… They would be very expensive and need to be well made to last long enough to be feasible - but as tech moves forward that would become more easily doable.



Is electronic paper like the tech used on Kindle screens a viable option here? I believe these screens are energy efficient but the initial cost might be prohibitive. Also, the black and white limitation is not very desirable. Color might be necessary.



E-Ink screens are indeed very energy efficient and only require energy to change the contents, not to maintain it. If one could be built large enough for a reasonable cost then yes I believe that could work well!

I think coloured e-ink is also being worked on.

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I wonder if there is a city with enough traffic and street design that would be conducive to this idea. I live in SF but I don’t think it would work here. Freeways would be a bottleneck that might make the solution pointless in the evenings.



Yes it is! That’s what people have to do in such crowded, small city like Hanoi. It’s like a sneak attack on people though because the rules of when the streets become one-way or two ways or one-way the other way change all the time, very much confusing people. Traffic cops also take advantage of this by “hiding” behind stop signs and jumping out of no way to catch people who didn’t know about the switch beforehand.

I agree! More transparency and machines don’t lie (most of the time).

Lastly, here’s a loop video of traffic in Vietnam :joy:

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In DC we have a parkway that is one way in the morning and switches in the afternoon, but is only one way for that rush hour window.



Nice. How do they deal with the sign problem? I think a bad solution would be a sign that says One-way from 4-5pm M-F Those signs are just confusing and overly complicated. I assume they use complicated signs along with a traffic cop to solve the problem.

We’ve talked about the possibility of using digital signs. Mechanical signs could be another option. Those simple black and white arrows could pivot and point the other direction. Maybe this could be coordinated with street lights to give a section enough time to clear before pivoting.



They do have cops that do the switch over. It’s also interesting to see on the bridges with the modular barriers, a huge machine moves it over to give one side another lane in rush hour. The combination of way more people on the road plus distracted driving makes traffic so bad around here. I think the lights need to be timed better as well, to give priority to people heading in or out of the city.



Just been looking at road rules in Canada for an upcoming holiday and found this:

It would seem they already do this? Perhaps this can be used as a reference for anyone wishing to encourage this :slight_smile:



Around Vancouver (Canada) we have the George Massey Tunnel to the south and the Lions Gate Bridge to the North, both of which switch lane directions according to rush our demands.

First they switch the X signals, then they flop the lane guard rails, and finally they send across a friendly soft bumpered traffic plow to clear the way.