Roundabout

Our area has gone wild with roundabouts in the last few years. Once I get used to one, it's no better or worse to me, so if there is a benefit overall, that's good. It is a bit disconcerting when I encounter a new one where I thought I knew the intersection.

That one isn't bad.?ÿ But you should see the one's they've built in NH.?ÿ Very tight circles, pretty much every tractor trailer has to ride up into the center, which might be the reason why it's sloped granite curb and concrete in the middle.?ÿ Still not right, in my opinion

Posted by: @jph

Very tight circles, pretty much every tractor trailer has to ride up into the center, which might be the reason why it's sloped granite curb and concrete in the middle.?ÿ Still not right, in my opinion

As someone who really does like roundabouts, I agree with this... Build 'em the right size or don't build 'em at all.

Do they teach roundabout rules in US driver's education programs these days? I don't remember learning about them.

Do they teach roundabout rules in US driver's education programs these days? I don't remember learning about them.

Silly Rover,

You're dating yourself.?ÿ They don't teach driver's ed anymore.

Southern roundabouts.

@jph Very minimal and tight ROW's in which to work within.?ÿ Many of those roads in NE haven't expanded much beyond their original traveled ways from 1700s

@ric-moore?ÿ

Generally true, but the ones I'm thinking of, just west of Keene on Rte 9, there's plenty of room.?ÿ

I'm picturing the design engineers with modelling software, squeaking out the exact necessary room for a tractor trailer to make the turn, giving no leeway or having real-world knowledge.

Attended a seminar once given by FHWA about ADA design, at that time they were pushing for more roundabouts, but admitted that they are NOT friendly insofar as ADA compliance. They showed a video where the pedestrians with different disabilities were having much difficulty navigating the roundabout, in some instances drivers would stop, get out and assist them.

@rover83?ÿ

I believe the philosophy is that if they are wide enough without the roll curb for large trucks to make the turn, then car drivers would ignore that they are, in effect, two lanes wide and just fly through them creating a hazard that the roundabout is meant to prevent. The same reasoning is why they put artworks and whatnot in the centers, they want the approaching drivers to look to the left at what's coming and not be concerned with vehicles all the way on the other side.

There are 3 roundabouts on Route 20 in Lake County, at Route 53, at Route 29 and a local intersection west of that. At first I thought it was weird to put a roundabout on a State Highway but now that the drivers are used to them they work very well.

@john-putnam?ÿ

Driver's education is offered through most high schools and is a big money maker for private firms.

Posted by: @rover83

As someone who really does like roundabouts, I agree with this... Build 'em the right size or don't build 'em at all.

I visited Providenciales a couple of years ago. They have little traffic circles with rolled curb. You should try maneuvering a roundabout at 55 mph on the left side of the road, yikes.

?ÿ

@dave-karoly?ÿ

Also one on Highway 49 in the huge metropolis of Plymouth California.

Posted by: @rover83

Posted by: @jph

Very tight circles, pretty much every tractor trailer has to ride up into the center, which might be the reason why it's sloped granite curb and concrete in the middle.?ÿ Still not right, in my opinion

As someone who really does like roundabouts, I agree with this... Build 'em the right size or don't build 'em at all.

Do they teach roundabout rules in US driver's education programs these days? I don't remember learning about them.

?ÿ

Roundabouts save money, eliminate T accidents (which are some of the worst for fatalities), do not lose power, have no lights to replace, calm the flow of traffic, etc.

I believe that they are the standard around here, to be preferred over lights. But, there isn't always a lot of room, so some are very tight. The rolled curb in the middle seems to work fine, I assume it is reinforced for truck use.

There is a variation in Seattle. They are using traffic circles almost exclusively for traffic calming all across the city. There are hundreds of uncontrolled intersections with no signage or anything else across the city's older residential neighborhoods. They have come in and put planters in the center of each intersection without any other improvements. This makes for a VERY tight circle. Also, it means that all sorts of monuments had to be reset, and it generally makes surveying a bit more difficult.?ÿ

?ÿ

I rolled into this sucker one morning on my way from the airport to my hotel, and did 3 or 4 circuits before I could get out of it (scared the crap out of me).

Fun Time at the roundabouts.....

Posted by: @jph

@ric-moore?ÿ

Generally true, but the ones I'm thinking of, just west of Keene on Rte 9, there's plenty of room.?ÿ

I'm picturing the design engineers with modelling software, squeaking out the exact necessary room for a tractor trailer to make the turn, giving no leeway or having real-world knowledge.

I won't speak for the highway engineers but I will for private site, land development civil engineers. They have the real-world knowledge. But when the municipality adopts DOT turn standards and the client wants that extra lease space, it doesn't matter. If the standard is insufficient, change the standard. They will advise their clients all day--but unless the municipality demands more, they'll be designing so that there's only an inch of play as per their client.

@jaccen?ÿ

I'll give you that.?ÿ Just if you saw some of these NHDOT ones, there's plenty of green space all around.?ÿ Then again, all land is owned by someone, so maybe that's the result when paying the abutters by the square foot for the takings

@mathteacher And I'm headed to the first NASCAR roundabout in February.?ÿ My wife and I love NASCAR racing, even if it ain't as good as it used to be.

Andy