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by UncleEntity 1544 days ago
Phoenix area added a bunch of roundabouts a while ago and last I heard they were in the process of taking them out.

Problem is if people are used to them they work well but if you rarely see them people don’t really understand the concept and just kind of blast through them without yielding.

Almost got taken out a few times when I was a cabbie, people just go full speed into them without looking.

The new hotness seems to be intersections where the traffic crosses over to the other side and left turns are uncontested(?).

2 comments

>Problem is if people are used to them they work well but

(un)friendly reminder that this goes for the people in the city plannign department first and foremost.

You can't just dump one in at every intersection and expect them to work out. It only works out when there's similiar traffic volumes on the intersecting streets.

Of course people just drive on through when the volumes are such that that's the prevailing flow.

Not that I have anything against 2-way stops but that's basically what you create a lot of when you start carpet bombing your town with roundabouts because they're trendy.

Britain has mini-roundabouts, which are a good alternative to many smaller junctions. It's just a painted white dot, about the size of a small car, in the middle of the junction.

Since the "circle" is so small, you yield to approaching vehicles on the junction, but also to a vehicle waiting at the entrance to your right¹, i.e. the vehicle that is waiting in the direction you're looking in anyway for traffic on the "circle".

If there are no other cars, you barely need to slow down.

In most cases, even if the junction is busy, a car trying to enter from an uncommon direction will quickly be able to go as someone in the main direction will need to yield.

¹ Driving on the left in Britain, of course.

2-way stops often feel stressful or unsafe if there is any significant traffic. Roundabouts seem like an improvement with the much lower chance of being t-boned.
> intersections where the traffic crosses over to the other side and left turns are uncontested(?).

Diverging diamond interchange[1]?

[1]: https://en.wikipedia.org/wiki/Diverging_diamond_interchange