4-way stops vs. roundabouts: which is more efficient? Mythbusters tests both (vid)

[brucey]

Originally Posted by MetroMPG

Funny!

Maybe suspicion about roundabouts is a side-effect of general wariness (in some quarters of the U.S.) about things "European".

I think you're right. Many people I know would love them if they were labelled "American inventions". Nationalism is still alive and well here.

[jakobnev]

Freedom circle.

[euromodder]

The utter madness of the US 4-way stop is that you ALWAYS have to stop.
Even when there's no-one else around ... but a copper hidden somewhere behind a bush or sign.
So everyone has to come to a full stop.
Always.

Mythbusters obviously tested the roundabout in what is its LEAST efficient operating mode : when there's lots of traffic coming from all directions.
In this case, traffic on the roundabout tends to hinder traffic getting onto it.
That's when they usually get additional traffic lights in Europe, if the road authority is smart, these only work during peak hours.

[euromodder]

Originally Posted by cbaber

I wonder if traffic sensing stop lights would make a difference for the 4-way.

It surely would, if it means you won't have to stop when there's no cross-traffic.

But they still make people stop.

Unless traffic is pretty dense, you can time the arrival of another car on a roundabout, and adjust your speed to sneak in behind it, or in between 2 cars.

[euromodder]

Originally Posted by t vago

Was a bit unhappy earlier, because I could not see the YouTube video because OpenDNS (which I WAS using) blocked it as being a "video sharing website".

Must be something else I'd say.

I'm using OpenDNS name servers as well.
No issues seeing the YT vid
(OSX 10.8.5 , using Safari 6.0.5)

[darcane]

Originally Posted by cbaber

I wonder if traffic sensing stop lights would make a difference for the 4-way.

We have those all over (western Washington) and... no. Typically, the lead cars heading towards a red light will have to slow down and often stop before the sensors are triggered and the light turns to green.

In Anchorage, AK, they have timed lights and the prevailing traffic heads one direction through many intersections (basically, N-S south of downtown and E-W east of downtown). Because of this, they time the lights so you hit green lights at every intersection as you go through the city along the primary route. This works very well (probably even better than roundabouts)... until you try to take one of the side streets.

I love roundabouts, and we are starting to see them show up in Washington. Near my old house, there was one traffic light that I had to wait at for about 20 minutes a day as rush hour traffic slowly filtered through it (1+ mile backup every day). Once it was replaced with a roundabout, there was NEVER any delay.

[jeff88]

When I went to England/Scotland, there seemed to be a lot of round abouts and in the well-poulated areas they had street lights. I *think* they only turned on at peak hours.

I like overpasses. Here in San Jose, most of the expressways are 50MPH. There are intersections, but when two E-ways cross, there is almost always an over/under pass. Then to transfer roads, there are auxillary roads to exit one and merge onto the other, usually in a 'U' fashion, but not a hairpin turn. They work really well, keeping traffic flowing at a steady pace. The nice thing about the auxillary roads is they give you a good excuse to have an office building or restaurant or similar.

[t vago]

Originally Posted by euromodder

Must be something else I'd say.

Windows XP Pro SP3, running Firefox 24 and Chrome 30.0.1599.69, over a WNR3500L with DD-WRT, and an OpenVPN pipe to Canadia.

Nope, definitely was OpenDNS. It was an OpenDNS page that informed me of the blockage, the video was still blocked when I rebooted my router two different times, and once I went to Google's public DNS servers, the problem itself went away and I could see that video above.

I'm now using OpenNIC.

[320touring]

Originally Posted by jeff88

When I went to England/Scotland, there seemed to be a lot of round abouts and in the well-poulated areas they had street lights. I *think* they only turned on at peak hours.

Roundabouts can be damn effective-but that relies on the people using it correctly

Over here (Glasgow), there's a myriad of roundabouts with full time lights..

at peak times this means significant tailbacks on approach to the roundabout

classic example here
http://goo.gl/maps/JEjwF

this frequently backs up on to the m74 motorway, and approx a mile up the a725 at peak times-hardly a beacon of efficiency

At other times the lights often means stopping for no reason (like a 4 way stop)

so they aint flawless

[jeff88]

320touring, that's why, although roundabouts are effective at times, I prefer overpasses with auxillary roads. The only traffic congestion possibility is where you merge onto the next E-way, but the auxillary road is usually long enough to not effect the traffic on the first e-way if the line to merge gets too long.

I'll post a screenshot of the two expressways I'm talking about like you did as soon as I get home.