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Safer roundabouts are replacing traffic signals (2023)

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11–20 of 85 posts

Re: Safer roundabouts are replacing traffic signals (2023)

#11
post #6

No HN discussion of roundabouts is complete until someone has posted the Magic Roundabout. There are several in the UK, this is the one nearest to me. And yes it's as insane to drive on as it looks, but safer as everyone is terrified and drives slowly. https://en.wikipedia.org/wiki/Magic_Roundabout_(Hemel_Hempst...

That is nuts!

The weirdest thing we have here (unrelated to roundabouts) is the hook turn which cars must obey at many intersections in the city:

https://en.wikipedia.org/wiki/Hook_turn

Re: Safer roundabouts are replacing traffic signals (2023)

#12
post #3

Trying to explain how roundabouts work to someone who doesn't get them is extremely frustrating. The rules are simple, but for some reason a lot of folks are vastly overthinking it. The thing is, I like roundabouts, but I'm somehow not surprised that the metrics focus on accidents involving death or injury. I think that because people have to slow down, it must improve those metrics. But there's a particular glut of…

> But there's a particular glut of bone-headed people who power right into the roundabout without anything resembling yielding

Near my house are roundabouts that I have to drive in all the time. My number of near-collisions from people barreling through is ridiculous. Now if I'm in the roundabout I lay on my horn if I see cars approaching because they just don't pay attention.

It's sad they're so dangerous because of oblivious idiots. Those intersections are so much more efficient as roundabouts than if they were traditional four way stops.

Re: Safer roundabouts are replacing traffic signals (2023)

#13
Carmel, Indiana has over 150 roundabouts and they are building more. I believe we have less than 5 traffic light intersections now but I'm not 100% sure.

The movement around Carmel is remarkable compared to driving next cities (Indy, Fishers, etc). Fishers and Westfield are building more roundabouts as well.

As for one person who commented about high traffic locations - Carmel would make an overpass for those intersections though they are not many.

Re: Safer roundabouts are replacing traffic signals (2023)

#14

Carmel, Indiana has over 150 roundabouts and they are building more. I believe we have less than 5 traffic light intersections now but I'm not 100% sure. The movement around Carmel is remarkable compared to driving next cities (Indy, Fishers, etc). Fishers and Westfield are building more roundabouts as well. As for one person who commented about high traffic locations - Carmel would make an overpass for those interse…

https://eri.iu.edu/erit/case-studies/carmel-indiana-roundabo...

https://www.carmel.in.gov/government/departments-services/en...

https://www.carmel.in.gov/home/showpublisheddocument/21496/6...

https://youtu.be/SIS6mdfu8Lw

https://www.ite.org/technical-resources/ite-talks-transporta...

They intend to replace the last 14 of 15 traffic signals remaining with roundabouts, leaving the last one (located at Main and Range Line) for historical purposes, as it was the first in the state and one of the first in the country.

https://readthereporter.com/the-first-will-soon-be-the-last-...

https://web.archive.org/web/20240713203110/https://www.youar...

Re: Safer roundabouts are replacing traffic signals (2023)

#15

I live in a country where roundabouts are common. They're great for relatively low traffic intersections as you can often get through much faster than lights. They are a liability when traffic levels are high enough - say during peak times - when one inbound direction is blocked by another. Wondering why Americans loathe them?

I don’t think Americans loathe roundabouts. They’re just unfamiliar. So when someone says “would you like to add an unfamiliar section of road design in our town?” most say no.

Re: Safer roundabouts are replacing traffic signals (2023)

#16

Having looked at some of the links in the article, I just realized that one extra feature of roundabouts is that they allow U-turns (which is not always the case at an intersection).

They even allow you to do a couple turns until you decide next action (although my wife hates it).

Re: Safer roundabouts are replacing traffic signals (2023)

#17
post #3

Trying to explain how roundabouts work to someone who doesn't get them is extremely frustrating. The rules are simple, but for some reason a lot of folks are vastly overthinking it. The thing is, I like roundabouts, but I'm somehow not surprised that the metrics focus on accidents involving death or injury. I think that because people have to slow down, it must improve those metrics. But there's a particular glut of…

But do you have to explain? Isn’t it part of the studies one do in order to obtain a driving license in us?

Re: Safer roundabouts are replacing traffic signals (2023)

#18
Anecdotally, I also think the way roundabouts get built in the US is better now than a decade or two ago. It used to be that roundabouts (being unfamiliar) were just treated as a cookie-cutter object to plunk into the roadspace blindly.

Nowadays I often see the designers making conscious decisions like:

* what radius?

* what angle do we need so it doesn't even make sense to try to turn left?

* hard curb or drivable curb?

* central pit, flat center, or raised center?

* full roundabout, or teardrop-shaped (common on both sides of a highway bridge)? Apparently peanut-shaped is also a possibility though I haven't seen one.

* one-lane, two-lane, or a mixture (potentially including partial three-lane) depending on what part of the circle (common when there's a "major" road meeting a minor one)?

This is all of course ignoring the fact that drivers are also more aware of how to use them nowadays.

Re: Safer roundabouts are replacing traffic signals (2023)

#19
post #10

I spend a lot of time near Manchester, VT where there are a handful of roundabouts including two in quick succession, one of which is as small as it is busy. The problem, based on my observations, is that many Americans have no idea how to use roundabout, nor how to signal through them. I feel unsafe every time I'm in the roundabout and have nearly been T-boned multiple times by people feeling they have the right to…

It’s a chicken and egg scenario. Until they’re more common, people won’t learn. Hopefully we’re just in that awkward middle phase.

There's a path to that though: start with single-lane or turbo roundabouts with a turn at each entrance and you're golden.

Re: Safer roundabouts are replacing traffic signals (2023)

#20
post #6

No HN discussion of roundabouts is complete until someone has posted the Magic Roundabout. There are several in the UK, this is the one nearest to me. And yes it's as insane to drive on as it looks, but safer as everyone is terrified and drives slowly. https://en.wikipedia.org/wiki/Magic_Roundabout_(Hemel_Hempst...

...WTF.

The Wikipedia article doesn't even give any explanation as to why.

Why on earth did they build a circle of six roundabouts, rather than simply a single roundabout with six entrances/exits?

I'm baffled.

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