I've designed several roundabouts in place of road widening and turn lanes at subdivision and apartment entrances. The planning office was really bent on trying to put them in as many places as possible. So Forsyth county North Carolina can blame the planning department. Now, as I drive through that county I don't notice as many more new roundabouts at newer developments. In the right place at the right time, they work great, but that many lanes would barely work in the US. It would be a pile of wreckage and road rage.
And driving in any foreign country is a complete clown show compared to US roads. I don't think I've ever seen a stoplight obeyed in Mexico.
New York seems to be having a love affair with roundabouts lately. The problem is that as you say, they only make sense in the right place and the right time -- and those places and times are far fewer than the number of roundabouts they've been building.
A few months ago I had occasion to drive through some dinky little city that had four or five of them in a row on what passed for the main drag. In case the idiocy of that isn't self-apparent, remember that the traffic already in the circle has the right of way, and the traffic entering the circle has to yield. But what happens when the traffic at at a roundabout exceeds the traffic at the previous one? The answer is that the entering traffic backs up all the way into the previous circle.
In the best-case scenario, the drivers in the first circle would just, well, circle until they could exit, and all the other drivers would wait to enter the circle. The problem is that even assuming the best-mannered and most skillful drivers in the world, the circle itself blocks the view of the mess at the next roundabout, thanks partly to the planners' additional measure of idiocy as expressed in putting monuments in the middle of every roundabout. So drivers wishing to enter the traffic can't tell that the traffic from the next roundabout is backing up into the one they're about to enter.
On a more general note, I can't help but think that there's some graft involved in all this roundabout building. There's one about an hour from me that replaced a simple intersection of a county road coming off a state highway (County 357 and NY 28 in North Franklin, NY if you want to look it up). The county road terminates there and used to have a simple stop sign. For reasons that I can't even imagine, they decided to replace it with a roundabout.
It's just a simple roundabout and it doesn't create any problems. One would have to be an utter idiot to screw it up. It's just that it's completely unnecessary. County 357 is a lazy road with very little traffic at even the busiest hours. NY 28 is a bit busier during what passes for "rush hour," but it's still not exactly the Autobahn.
As far as I'm concerned, it looks to me like someone's brother-in-law needed the work. That's the only reason I can come up with for planting a roundabout there.
Rich
Pennsylvania is also seeing the roundabout as the solution to the worlds problems. Coming into KAVP they installed not one but two roundabouts. It’s hilarious.
