WorldLux

(I release that I'm getting OT here)

Are you referring to this

or turbo roundabouts?

Turbo roundabouts are even easier to navigate through. You select the lane for the direction you want to go to, obey the signs/traffic lights and stay in your lane.

bibbju

Ah yes, the Canary Wharf roundabout! (or one of them - there's one at each entrance to the Wharf with the same "art installation"). The one in the photo's okay. It's the other one (by Westferry Circus) that can catch you out occasionally

Cloudship

No, they were up near Halifax. Maybe it was a turbo roundabout. In any case, I certainly had enough to deal with without having to worry about coming to a stop in the middle of it.

emma69

No, I don't think they are talking about turbo roundabouts, but of the older spiral roundabouts which were built to be regular roundabouts, then something happened to increase or change traffic flow, and they had to insert traffic lights, so that people didn't get stuck forever! You still have to change lanes as you go around (the better ones have markings that help) but there are random red lights mid way around as well (the one I used to drive had lights on each road entering, and at 2 points on the actual roundabout itself, so if you were going all the way around (back on yourself) you would enter at 6 (imagining a clock face) once those lights go green, get stopped by another set of lights at 10, and another set of lights at 3 before exiting again at 6.

Cloudship

Yes, that is what I am talking about. lights on the roundabout itself.

I did look up the turbo roundabout. That would result is mass casualties if they tried to do that here.

ajGoes

The first one in the UK opened in the summer of 2014. It had had no accidents from that time till July '15. I don't know how it's fared since.

MissJ

Seriously, all of the USA would be a barren wasteland of wrecked cars and bodies if turbo roundabouts were everywhere.

WorldLux

There are very easy actually. You would just need to install 1) traffic lights and 2) physical separators to get people used to the idea. After that it's a piece of cake.

Cloudship

So anotherwords, make a regular intersection?

WorldLux

Not exactly as it allows drivers to drive "around each other". It's essentially mixing the advantages of intersections and roundabouts. Two opposing roads leading into the roundabout can drive simultaneously in all directions.

And while turbo roundabouts (especially versions with 3 or 4 lanes in the roundabout) usually look scary and strange on paper, they are very easy to navigate and help reduce congestion as they eliminate the fears of many drivers "that they won't be able to get out of an inner lane".

It works miraculously in roundabouts where the outer lane would usually be full, while nobody uses the inner lanes. Drivers start to use all 3 or 4 lanes and hence reduce congestion.

MissJ

Where I live, people would get in the wrong lane and then just stop. Or plow over the barriers because they didn't pay attention.

We got a few diverging diamond intersections when I lived in ATL and it was like Mad Max for a while. People just drove through multiple lanes, even encountered cars on the wrong side of the road a few times.

Cloudship

The problem I see with Turbo roundabouts, at least in the US case, is that it assumes everyone knows what turnout they are going to be using and which lane to get in, it also assumes that people would let the person who is getting off at say the third exit over into the outer lane. Those types of things don't happen here.

The US actually does have a fair number of rotaries in parts of the country. One we have near me got those same markings a few years ago as the turbo rotary (without the rigid traffic control devices). Needless to say it is a mess. nobody knows what lane to e in, people cross lanes, people dont see cars in the outer lane and just drive into the rotary and people from the inner lanes cut others off trying to get to their exit. By now the markings have worn away and nobody even pays attention to them, so it is getting better.