Over 7000 roundabouts in America

[tradephoric]

Here is a Google Earth KMZ file that contains over 6000 modern roundabouts in America.

http://www.mediafire.com/file/j6zcvi91whg3j2u/Roundabouts+%282019-02-12%29.kmz

[NWI_Irish96]

Only half of those are in Carmel, IN.

[kphoger]

They're all crash-prone.

[TechZeke]

I can deal with roundabouts; it's the other idiots that can't seem to figure out how to properly yield that make them unpleasant for me. I have to pray that I don't get cut off from when another car approaches when I'm already in the roundabout.

[abefroman329]

I can deal with roundabouts; it's the other idiots that can't seem to figure out how to properly yield that make them unpleasant for me. I have to pray that I don't get cut off from when another car approaches when I'm already in the roundabout.

Come to Chicago, where they installed roundabouts as traffic-calming measures on certain streets, but didn't provide any signage on how to use them, and consequently, many drivers make a left-hand turn by turning left at the roundabout.

[froggie]

^ Some of that could also just be Chicago/Illinois drivers.  You guys tend to be arseholes on the road....almost as bad as mAss or DC drivers...

[abefroman329]

^ Some of that could also just be Chicago/Illinois drivers.  You guys tend to be arseholes on the road....almost as bad as mAss or DC drivers...

Nah, this is a total Maryland driver move.

[kalvado]

^ Some of that could also just be Chicago/Illinois drivers.  You guys tend to be arseholes on the road....almost as bad as mAss or DC drivers...

Yeah, US drivers seem to be much worse than average american driver.
And drivers on planet Earth are mostly crazy...

[tradephoric]

There are currently about 50 triple-lane roundabouts in America and roughly half of those are found in Wisconsin.  Green Bay alone has 10 triple-lane roundabouts.  Does anybody have any safety numbers out of Green Bay?  The city must keep track of the most dangerous intersections in the city (whether it be total crashes or a list weighted by severity).

[kphoger]

Come to Chicago, where they installed roundabouts as traffic-calming measures on certain streets, but didn't provide any signage on how to use them, and consequently, many drivers make a left-hand turn by turning left at the roundabout.

Actual roundabouts, or just little bitty islands in the middle of the intersections?

[Ben114]

A good chunk of those are in Cape Cod.

[sparker]

.............and another sizeable chunk out in the rural areas of CA (CA 43, CA 154/246 junction, etc.).  Not particularly beloved by truckers, to be sure!

[Super Mateo]

Come to Chicago, where they installed roundabouts as traffic-calming measures on certain streets, but didn't provide any signage on how to use them, and consequently, many drivers make a left-hand turn by turning left at the roundabout.

Actual roundabouts, or just little bitty islands in the middle of the intersections?

Tiny islands. 110th and Talman, for example.

[kphoger]

Come to Chicago, where they installed roundabouts as traffic-calming measures on certain streets, but didn't provide any signage on how to use them, and consequently, many drivers make a left-hand turn by turning left at the roundabout.

Actual roundabouts, or just little bitty islands in the middle of the intersections?

Tiny islands. 110th and Talman, for example.

Well, assuming that's the type abefroman329 had in mind, then I don't see what's wrong with turning left in front of the little island.  I probably would.  The intersection you linked to, in fact, has stop signs on two approaches–just like a normal intersection.  That's not a roundabout, so why would people be expected to treat it like one?

[Super Mateo]

Come to Chicago, where they installed roundabouts as traffic-calming measures on certain streets, but didn't provide any signage on how to use them, and consequently, many drivers make a left-hand turn by turning left at the roundabout.

Actual roundabouts, or just little bitty islands in the middle of the intersections?

Tiny islands. 110th and Talman, for example.

Well, assuming that's the type abefroman329 had in mind, then I don't see what's wrong with turning left in front of the little island.  I probably would.  The intersection you linked to, in fact, has stop signs on two approaches–just like a normal intersection.  That's not a roundabout, so why would people be expected to treat it like one?

If there's no traffic, I don't see the problem cutting through on a left turn.  There isn't that much traffic at this location, anyway.  There are roundabout signs on the approaches, but even then, I just treat it like a normal intersection.

[kphoger]

Ah, I see the warning signs now.

Technically, warning signs don't tell you what to do, just what to watch out for.  I'm struggling to come up with any guidance in the Illinois Vehicle Code on what to do at a roundabout or traffic circle, so it's possible it's actually a legal loophole.

[froggie]

A good chunk of those are in Cape Cod.

Rotaries ≠ roundabouts

While both operate similarly in that traffic in the circle has right-of-way, rotaries in Mass are a noticeably larger radius than a roundabout.

[kalvado]

A good chunk of those are in Cape Cod.

Rotaries ≠ roundabouts

While both operate similarly in that traffic in the circle has right-of-way, rotaries in Mass are a noticeably larger radius than a roundabout.

Frankly speaking, there is no maximum roundabout diameter defined by FHWA. There are  minimum and recommended values (only for 4-leg 90 degree intersection), and mention of larger dimensions for high speed situations.  Larger diameters "should generally not be used", which is a pretty weak limit. 

[kphoger]

These definitions are actually irrelevant to the topic at hand.  The 6000 figure posited by the OP came from a file with a specific data set.  Ben114's reply about a good chunk of them being on Cape Cod is therefore either objectively true or false.  If the data set doesn't include a sizable number of entries from Cape Cod, then he's wrong.  If it does, then he's right.

And more to the point of rotaries... if they are included in the data set, then they're part of the 6000.  If not, then they aren't.

[MantyMadTown]

Manitowoc, WI is also planning a roundabout at the intersection of WIS 42 and Maritime Dr. That one's not on the map.
https://projects.511wi.gov/waldo/full-project-overview/

[jakeroot]

^ Some of that could also just be Chicago/Illinois drivers.  You guys tend to be arseholes on the road....almost as bad as mAss or DC drivers...

I've never got the impression that District drivers were dickheads. What's the common arsehole move that you've seen?

My mother's primary complaint has been that drivers dilly-dally too much. Taxi's in particular.

[froggie]

Oh where should I start...

- Flagrant illegal parking
- Flagrant red light and stop sign running, despite the District having red light cameras.
- Flagrant speed.  While I'll agree that the DC area freeways could stand to have their 55 (or in the District's case, 45 or 50) limits reviewed, far too many drivers consider city streets their personal dragstrip and will rush upwards of 50 in a 25-or-30 in order to "beat the light".

Much more prevalent on the DC/MD side of the Potomac than on the Virginia side, though there are plenty of hotheads in Northern Virginia as well.

[Road Hog]

Are there any freeway roundabouts? I could see this concept work in rural areas with lots of room for a wide radius to keep speed. Would save on overpasses and flyovers.

[kalvado]

Are there any freeway roundabouts? I could see this concept work in rural areas with lots of room for a wide radius to keep speed. Would save on overpasses and flyovers.

not exactly, but close: NY85 - divided 4-lane 55 MPH, 3 roundabouts within 1 mile stretch.
https://www.google.com/maps/@42.6444845,-73.8563279,1384m/data=!3m1!1e3

[tradephoric]

Are there any freeway roundabouts? I could see this concept work in rural areas with lots of room for a wide radius to keep speed. Would save on overpasses and flyovers.

This triple-lane roundabout in Wisconsin replaced a trumpet interchange about 10 years ago:

https://www.google.com/maps/@44.9210291,-91.3805333,156m/data=!3m1!1e3