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We're excited about our new roundabout

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Re: We're excited about our new roundabout

#132
post #108

This is oddly timely. I'm travelling in Europe at the moment and have been covering a lot of area with a lot of roundabouts where they would be signaled or signed intersections in the US. They definitely make traffic flow smoothly and I've noticed a few areas where they are used to eliminate dangerous left turns at places like parking lots, you leave turning right, hit the next roundabout to "uturn" then head back th…

I'm living in Germany, where roundabouts are very popular with planners recently. I would say they definitely have their place, but they are also overused. The (smallish) city where I live has a bypass road where for some reason it was decided to use roundabouts (I suspect the same reason why it has so many tight curves - not wanting to purchase too much land). With the result that using the bypass is not much faster than driving through the town, so barely anyone uses it.

Re: We're excited about our new roundabout

#133

I live in the US now, but originally from Ireland. My least favourite part of US road infrastructure is the 4 way stop. They are just not good compared to a roundabout. Half the time the only way you can tell it’s an all way stop is by looking for the back of the stop signs on the perpendicular road. With a roundabout, you only have to look in one direction, and if it’s clear, you don’t even have to stop.

> With a roundabout, you only have to look in one direction

When being taught how to ride a motorcycle, one of the lessons is a series of extra checks that you're not taught when learning to drive a car. These are known as lifesaver checks.

Entering a roundabout is a left turn in Ireland (right turn in right hand drive countries) so you would check over your left shoulder to make sure nothing was on your left. This is performed after doing a normal right and ahead check for traffic already on the roundabout.

I have never caught anything with a roundabout lifesaver (I have in other situations) but I can see how it's useful on roundabouts with multiple entry lanes, or if something like a bicycle had appeared on your right.

Re: We're excited about our new roundabout

#134
post #21

Australian who lived in Washington state for 4.5 years. Very happy to see those kind of changes. Much better and safer than 4-way stop intersections and I hope American drivers will figure out eventually how to use them

Aside from one old lady that I saw doing laps a few years ago after our nearby roundabout first opened, it seems like most people figure it out pretty quickly. But they're too comfortable with it, and most people blast through without even hitting the brakes. That brings its own problems.

I did wonder that. The article says it "slows traffic" but looking at the picture it's basically just lines painted on the ground. Does it really slow anything? A proper roundabout with a fully raised centre not only slows people down but forces you round so any collisions that do happen are minor glancing ones rather than catastrophic perpendicular ones.

Re: We're excited about our new roundabout

#135

Earlier quoted context omitted.

Aside from one old lady that I saw doing laps a few years ago after our nearby roundabout first opened, it seems like most people figure it out pretty quickly. But they're too comfortable with it, and most people blast through without even hitting the brakes. That brings its own problems.

I did wonder that. The article says it "slows traffic" but looking at the picture it's basically just lines painted on the ground. Does it really slow anything? A proper roundabout with a fully raised centre not only slows people down but forces you round so any collisions that do happen are minor glancing ones rather than catastrophic perpendicular ones.

Generally, they are designed to naturally make the driver slow a little to see other cars on approach. Often it's paired with slight turns just before the intersection which also does the same thing partly. Some places (most?) actually put obstacles like trees to make it harder to see other cars from further away.

I suppose it depends on what is meant by traffic and I suppose it does depend on whether "slows traffic" means slowing down compared to just zooming past with a green, or drives at a slow speed. I would think that a) it slows traffic compared with zooming past and b) it's not that slower

On average, I suppose, smoothly moving traffic at slightly slower speeds will be more efficient than 3 lanes of stopped traffic and 1 of fast.

Re: We're excited about our new roundabout

#136
post #95

Earlier quoted context omitted.

Online I see this mentality that roundabouts are great no matter what and it seems really strange to me. It really depends on the design of the roundabout and the traffic conditions. Where I grew up there are a lot of roundabouts, but many of them are so dangerously designed I started actively avoiding them. It’s not that you can’t poorly design a four way stop, but it seems to be much less common, for whatever reaso…

My experience driving in rural France was that nearly every intersection was a roundabout and it slowed things down dramatically. Many, many times I was the only driver within sight. Surely one of the two directions is more used and a couple of putting stop signs the other way would make more sense. Roundabouts are great sometimes, but they aren’t a magic bullet. That said we have a nasty intersection in the area on…

That it slows things down significantly is a feature not a bug. Rural roads have a lot of accidents. In my country the most fatal ones. There are two main reasons for that: speeding and fail to yield. Often combination of the two. Roundabouts solve the issue as you have to slow down before the intersection.

Re: We're excited about our new roundabout

#138

Earlier quoted context omitted.

Painted roundabouts will be invisible when it snows.

People are generally driving significantly slower in snow though, so the need for a roundabout is lessened. And you can also install signage indicating a roundabout is there.

A roundabout requires signage in any case. At least in all countries I've seen one so far. Otherwise it's not a roundabout and may even have very different rules.

Re: We're excited about our new roundabout

#139

Earlier quoted context omitted.

I vastly prefer roundabouts, with a single exception. If traffic is heavy and dominated by the same entry and exit points, it can be hard to get a turn if you're coming from the side. Our nearest roundabout is this way. I once saw a roundabout with stop signs. I assume it was an attempt to address this situation.

In the UK, you get roundabouts with traffic lights at the entrances, sometimes only operational at peak times, and off most of the time. Works well

You do, but that means there is no roundabout when you need it the most.

The problem occurs mostly when the dominant flow is given multiple lanes.

A fairly common solution/workaround is blocking the view of the approaching traffic, forcing it to slow down. But again, this doesn't work well on large roundabouts that allow people to speed up to of 30+ mph.

Re: We're excited about our new roundabout

#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.

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