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We're excited about our new roundabout

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Re: We're excited about our new roundabout

#291

Post by dsego »

btbuildem wrote: post #250
dsego wrote: post #233

Earlier quoted context omitted.

A four-way stop would be confusing for me, those don't exist in my country as far as I'm aware. I was also thought that a stop or yield sign means I'm on the side road and the other road implicitly has priority.

The concept of priority and side road was too complex for North Americans. Yield signs virtually don't exist here.

It can get complex for us here as well, one example is when the priority road doesn't go straight through the intersection, eg. L-shaped main road, and then the other two have a stop and a yield sing. A lot of people where I live wrongly think that the yield has priority over the stop sign, it's a widespread misconception (I'd say more people believe it than not). In reality the priority to the right rule applies between side roads and the only difference between yield & stop is that the stop sign requires you to actually stop the vehicle. And then there are plenty of T intersections in smaller towns and villages where people assume the road going straight is the main road, even though there aren't signs and the priority to right would apply. I guess drivers mostly rely on habits and intuition.

Re: We're excited about our new roundabout

#292

Post by zippothrowaway »

lupusreal wrote: post #262
Symbiote wrote: post #224

Earlier quoted context omitted.

I'm not sure why the four way stop "makes the most sense". In Europe one road (perhaps arbitrarily) would be declared the main road, and the other road gets yield signs, or even just yield road markings (triangles).

If one is obviously a main road then it's a two way. If neither is, then it's a four way. If the intersection is lightly trafficked then there's not any reason not to make it a four way because it won't cause meaningful delays anyway. When a county has several hundred country road intersections that get a few dozen cars or less a day through them, it doesn't make sense to even spend time studying each one. Just throw…

Or do what they do in the UK. For all of these, make them 'mini-roundabouts' which is literally a dot painted on the center of the road. You follow the rules of the roundabout without building one. Works just as efficiently as a four way stop with light traffic - actually more, since you don't need to stop if the intersection is empty.

Re: We're excited about our new roundabout

#293

Post by balfirevic »

ToucanLoucan wrote: post #271
sethammons wrote: post #153

Earlier quoted context omitted.

What does the stop provide that a yield does not? I am confused

A distressing number of people who don't understand roundabouts will just blow straight through them.

They don't have to understand roundabouts specifically, there is supposed to be a yield sign when entering a roundabout - do they not understand the yield sign?

Re: We're excited about our new roundabout

#294

Post by cameronh90 »

robjwells wrote: post #222
cameronh90 wrote: post #214

Earlier quoted context omitted.

Roundabouts not good for pedestrians and cyclists. In London we’ve been replacing roundabouts with other types of junction to improve pedestrian and cyclist safety. We don’t have four way stops though so instead it’ll be min/maj junction or traffic lights.

This is only true of typical UK-style roundabouts which are designed for motor vehicle throughput. It’s extremely common in the Netherlands to replace crossroads and T-junctions with roundabouts to improve safety, but Dutch urban roundabouts are designed with safety as the main priority. This is achieved through single lanes, sharp entries, limiting forward visibility, and pedestrian and cyclist priority (via what ar…

We should absolutely be deploying these where we can, but they do take up a lot of space relative to their traffic throughput, and are only really suitable for a fairly narrow range of traffic volumes.

NL seems to quite commonly have this kind of physically large but medium traffic suburban junction, but outside of Milton Keynes and the outskirts of some towns that got heavily developed in the 60s, it's hard to see many places where we could just drop it in.

Re: We're excited about our new roundabout

#295

Post by IneffablePigeon »

malermeister wrote: post #226
tmnvix wrote: post #140

Roundabouts get a lot of praise whenever they're mentioned, and from a traffic flow perspective that's understandable - if by traffic you mean motorised traffic. For pedestrians and cyclists they are worse than the alternative (lights - or even a simple intersection) in my opinion. > Making a roundabout for everyone ctrl-f "walk", "cycl", pedes". Nothing.

The Dutch roundabout design is amazing for cyclists. See here [0] for a more detailed explanation, but the tl;dr is: Second, outer ring that's a bike lane - motorized traffic has to yield so bikes never have to stop and lose momentum. [0] https://bicycledutch.wordpress.com/2015/10/13/explaining-the...

In Cambridge we have recently had both our first Dutch roundabout and our first few Cyclops [0] junctions and I have to say I actually prefer the cyclops. Yes, you lose momentum if you want to turn and the throughput doesn’t match a roundabout but you can use it as a normal cross roads if you want or use the protected turn with lights around the ring without worrying about whether cars have actually seen you and understood that it’s your right of way. My opinion might change if I lived somewhere where people were used to Dutch roundabouts.

[0] https://cities-today.com/uks-first-cyclops-junction-opens-in...

Re: We're excited about our new roundabout

#296

Post by tinodb »

lupusreal wrote: post #264
realityking wrote: post #248

Earlier quoted context omitted.

Or, in the absence of any signage, it'd just be "right before left". Relatively common in the outskirts of cities where there isn't one road that has significantly more traffic than the other one.

Right before left is how four-way stops work. Putting the signs up doesn't cost much, so why skip them?

No, that’s not the same. On a 4-way stop you have to completely stop. Also how I remember my year in the US (I’m from NL) is that the first to reach the stop has right of way, not the “left” one. But I might be wrong on that last one? Didn’t have a drivers license at the time (but was surprised - and turned off from - 4-way stops).

Re: We're excited about our new roundabout

#297

Post by tinodb »

cameronh90 wrote: post #294
robjwells wrote: post #222

Earlier quoted context omitted.

This is only true of typical UK-style roundabouts which are designed for motor vehicle throughput. It’s extremely common in the Netherlands to replace crossroads and T-junctions with roundabouts to improve safety, but Dutch urban roundabouts are designed with safety as the main priority. This is achieved through single lanes, sharp entries, limiting forward visibility, and pedestrian and cyclist priority (via what ar…

We should absolutely be deploying these where we can, but they do take up a lot of space relative to their traffic throughput, and are only really suitable for a fairly narrow range of traffic volumes. NL seems to quite commonly have this kind of physically large but medium traffic suburban junction, but outside of Milton Keynes and the outskirts of some towns that got heavily developed in the 60s, it's hard to see m…

I don’t think they do!

> That the Dutch roundabout, including the cycle tracks all around it, can be built in almost the same space of a traditional junction is the reason why so many are being converted.

From: https://bicycledutch.wordpress.com/2014/02/23/junction-desig...

Re: We're excited about our new roundabout

#298

Post by Symbiote »

lupusreal wrote: post #262
Symbiote wrote: post #224

Earlier quoted context omitted.

I'm not sure why the four way stop "makes the most sense". In Europe one road (perhaps arbitrarily) would be declared the main road, and the other road gets yield signs, or even just yield road markings (triangles).

If one is obviously a main road then it's a two way. If neither is, then it's a four way. If the intersection is lightly trafficked then there's not any reason not to make it a four way because it won't cause meaningful delays anyway. When a county has several hundred country road intersections that get a few dozen cars or less a day through them, it doesn't make sense to even spend time studying each one. Just throw…

And then every single car must stop. That's a huge waste of energy.

The European way requires half as many signposts, and at most half as much stopping and starting of cars.

Re: We're excited about our new roundabout

#299

Post by Symbiote »

ifwinterco wrote: post #178
Plasmoid2000ad wrote: post #170

Earlier quoted context omitted.

Roundabouts with traffic lights are a bit of a failure alright - and the larger ones are i'd argue not roundabouts at all - they just share the shape. I believe traffic lights are always trying to solve a capacity issue - where the roundabout has hit it's maximum capacity and is suffering some throughput issue, which tend to sort of get exponentially worse. With traffic light sequencing, particularily dynamically, th…

The issue that can happen is when one direction has significantly more flow than the other - in this case you end up needing traffic lights otherwise nobody can ever pull out from the minor direction at rush hour. The other issue in the UK is massive signalised roundabouts used for junctions where traffic volumes clearly justify a proper grade separated junction like a stack, purely to penny pinch. South Mimms A1M/M2…

Bridges take a lot of space (to make a gentle enough slope) and I think in many cases in Britain, that space isn't available.

Fixing one junction might just move the congestion to the next one, and if you continue fixing them you turn all the cities into jungles of concrete.

Re: We're excited about our new roundabout

#300

Post by Symbiote »

bigstrat2003 wrote: post #96
buffaloPizzaBoy wrote: post #57

Whats not mentioned in the article is that this particular intersection has a (15mph residential access road - top right) (25 mph farmland road - bottom) (50mph country highway - left and right) Previously, only drivers from the 15mph and 25mph roads had to stop! Visibility coming from the south would also be terrible to check for incoming highway drivers (left is blocked by foliage, right the road curves out of sigh…

> Previously, only drivers from the 15mph and 25mph roads had to stop! This is something which drives me crazy with a decent number of roundabouts that the Wisconsin DOT constructs. You have a rural intersection where a local road crosses a major highway, and the local road has a stop sign in either direction. Then the DOT slaps a roundabout in there, greatly inhibiting the highway traffic which is 95% of the traffic…

Fast traffic on rural roads can be a major cause of accidents. The roundabouts slow everyone down and keep them slightly more alert.

(Not sure if this is the reasoning Wisconsin would use though.)

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