Roundabouts have the unfortunate property of smoothing throughput from a sequence of chunks and gaps to a constant dribble. That's fine on limited access roads with overpasses and parallel feeder roads for local traffic or where overall throughput is always low enough to still comfortably cut in from a lower rank junction. On everything in between (enough traffic to make turning difficult, but still having direct junctions with access roads) you are better off with the occasional traffic light that will as a side effect serve gaps to meet rank junctions downstream.
I hate roundabouts. I live in France, and we have them everywhere. They're a huge clusterfuck that does not win any time, and when misused can be a lot more dangerous than a properly planned intersection. Of all the accidents I've driven past on my daily drives, all of them happened on roundabouts. I hate them.
> Of all the accidents I've driven past on my daily drives, all of them happened on roundabouts.
In localities with few/no roundabouts, the vast majority of accidents still happen at intersections. Intersections of roads are the most prone to accidents (for fairly obvious reasons), with or without roundabouts.
I believe there is research showing roundabouts are actually quite a bit safer in general, but it's possible it depends on various things. But anyway, accidents happen mostly where two roads intersect, either way.
> People, bikes, buses, trucks: all face difficulty or death in their presence.
Roundabouts make my bicycle commute way faster. This in The Netherlands where we cycle a lot. Difficulty or death is entirely incorrect. Suggest to compare the designs across countries, maybe there's a huge difference in the design?
I think the issue comes when people try to circumvent the give-way priority - which gets worse when there are multiple lanes and multiple exits.
It certainly seems to be a people problem rather than a roundabout deign issue from my experience?
People trying to "beat" people out onto the roundabout rather than giving way, people not using proper lane discipline and squeezing/cutting into other lanes etc..
> They're a huge clusterfuck that does not win any time
Research shows the opposite. They can handle more traffic within a given timeframe. The bit about accidents seems strange. Not sure why you'd think that. I'm wondering if your roundabouts have some kind of design flaw.
Well, having driven on France on holidays, the problem seems to be with the driving culture. The roundabouts are very busy, and likely as a result drivers dart out in the shortest possible gaps in traffic. If you decide to play it safe, then the backed up traffic behind you starts honking at you, increasing the pressure and pushing you to make a bad decision. I found it very stressful indeed! (Perhaps all of France is not like this).
The Place Charles de Gaulle Étoile (Arc de Triomphe) in Paris is a gigantic roundabout, with the peculiar feature that traffic entering the system has priority ; traffic already on the roundabout must yield. This would lead to perpetual gridlock were there no traffic lights controlling access to the roundabout. This kind of junction used to be common in cities.
Out in the countryside roundabouts in France operate in the "normal" way : approaching traffic yields to traffic already in the system, with the usual triangular "yield" sign making priority clear.
It's possible that your experience of French roundabouts is related to driver confusion between these two systems.
The research I've seen suggest roundabouts do indeed cause accidents, but they're always low-speed accidents where people don't die. Intersections on the other hand are more likely to cause deaths because speeds can be much greater.
They take space for anything at reasonable size I'd guess.
Strangely enough though it's one of the few things I miss about the city I grew up in (Jeddah, Saudi Arabia) - lots of outdoor art and sculptures because they had lots of very large roundabouts (check Google images to see what I mean about the outdoor art).
America cities have too many oversized streets and major intersections. Keep the streets small and you don't need as many intersections and you can invest more in the ones you have. This is what they do in the Netherlands.
Wisconsin has become one giant series of roundabouts across the state over the past decade; they’re everywhere after new construction and being retrofitted whenever the opportunity arises. Sometimes 2 and 3 roundabouts connected at times.
> In cities, they are death traps for pedestrians and cyclists.
I haven't experienced that for the many roundabouts we have in The Netherlands. Throughput is higher (can easily be measured), plus waiting time is lower thanks to roundabouts.
Not exactly sure what you mean with "burbs" though it doesn't matter as they're heavily used in cities here.
I ride my bike through rotaries (as we call them here in Mass.) all the time. It's not that hard. It is advisable to try to ride as fast as possible, but the key is to signal clearly all movements in and out of the lane and the circle.
