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National Boards => General Highway Talk => Traffic Control => Topic started by: jakeroot on April 19, 2014, 05:39:28 PM

Title: Largest signed roundabouts in the US/Canada
Post by: jakeroot on April 19, 2014, 05:39:28 PM
I've always been strangely interested in humongous roundabouts, even though they are functionally useless.

I found 3 huge roundabouts in Jupiter, Florida, but unlike the ROTARIES in the Northeast, these are signed prior to entry as roundabouts.

Weirdly, they were all built post-1990, so after the modern roundabout was introduced to America (near Las Vegas).

From North to South

Somewhat reasonable
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fi.imgur.com%2F0KTWins.png&hash=e64c9e50b01a7f2d4266dc82df21cd1019b590e0)

Pretty ridiculous
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fi.imgur.com%2F8kxwoD7.png&hash=a8f37df30c9b87b21297c1a303380fe2ca09b18a)

Do the engineers think they are funny?
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fi.imgur.com%2Fv2oCYvh.png&hash=43721abb08dc7801f0562e5c227381e94334368e)

And they are all signed properly
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fi.imgur.com%2FJp3LrBu.png&hash=88d6a0340ed7e6137ee1312927ce6dd44887b267)

But the pavement markings indicate that exiting from the inside lane is not suggested (solid white line typically is not prohibitive, at least not here in Washington), so I guess it's not a perfect roundabout(s).


Does anyone know why some of the northeastern states don't repaint their rotaries to at least look acceptable? So many rotaries are still unsigned--no wonder they are unpopular.


Do other people know of, more or less, "proper" roundabouts that are needlessly huge? Of course, only North America, because I know England has some monsters.
Title: Re: Largest signed roundabouts in the US/Canada
Post by: xcellntbuy on April 19, 2014, 06:29:16 PM
There are several large traffic circles in Hollywood, FL on FL 820 (Hollywood Blvd.).  They were designed as the city was being laid out and built as early as the 1920s.
Title: Re: Largest signed roundabouts in the US/Canada
Post by: Zeffy on April 19, 2014, 06:40:13 PM
QuoteDoes anyone know why some of the northeastern states don't repaint their rotaries to at least look acceptable? So many rotaries are still unsigned--no wonder they are unpopular.

Here in New Jersey, most of our rotaries (we call them traffic circles) have little to no pavement markings inside of them. For example, this circle, has no lane striping while inside the rotary...

(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fmaps.google.com%2Fmaps%2Fapi%2Fstaticmap%3Fcenter%3D40.5024044%2C-74.8534456%26amp%3Bsize%3D450x450%26amp%3Bzoom%3D18%26amp%3Bmaptype%3Dsatellite%26amp%3Bsensor%3Dfalse&hash=22aa72bc0f776cdbbf1558dced731737a3e189ea)

...but this one, closer to where I live, definitely does have lane striping, and that is only because this circle was a notorious death trap even after US 202 got a flyover.

(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fmaps.google.com%2Fmaps%2Fapi%2Fstaticmap%3Fcenter%3D40.5756083%2C-74.6289544%26amp%3Bsize%3D450x450%26amp%3Bzoom%3D18%26amp%3Bmaptype%3Dsatellite%26amp%3Bsensor%3Dfalse&hash=197db72e57dfaa8dcd167e4d1fa41ace91e46cbd)

However, some of our circles are being converted to the safer roundabout, because if you're new to driving and you see this

(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fmaps.googleapis.com%2Fmaps%2Fapi%2Fstreetview%3Fsize%3D350x350%26amp%3Blocation%3D40.574027%2C-74.628307%26amp%3Bheading%3D7%26amp%3Bfov%3D15%26amp%3Bsensor%3Dfalse&hash=5009e79350c3526bb4f308a3652a7dc4edadb2b9)

you'll probably remember your parents telling you to avoid circles at all costs and realize you're officially screwed.

Title: Re: Largest signed roundabouts in the US/Canada
Post by: froggie on April 20, 2014, 08:24:30 PM
Despite signage to the contrary, I'd argue the three Florida circles in the original post are traffic circles and not roundabouts.  Namely, the radius of the circle.  Roundabouts, by design, have fairly tight radii.  These Florida examples do not.
Title: Re: Largest signed roundabouts in the US/Canada
Post by: mhh on April 20, 2014, 09:21:59 PM
This one in Sterling Heights, Michigan isn't large in diameter but it's large in width; it's three lanes wide!

https://goo.gl/maps/BtSMA
Title: Re: Largest signed roundabouts in the US/Canada
Post by: Brian556 on April 21, 2014, 02:16:43 AM
Fort Worth, Texas:
https://maps.google.com/?ll=32.717815,-97.442368&spn=0.006328,0.012392&t=h&z=17 (https://maps.google.com/?ll=32.717815,-97.442368&spn=0.006328,0.012392&t=h&z=17)
This one is horribly signed. No roundabout signage; no BGS diagram sign either. US 377 and SH 183 pass through.
The worst thing is that traffic already in the circle has to yield to SB SH 183 traffic entering the circle. It is a very awkward angle to yield at, and it is hard to look at that angle for gaps in traffic. It would be even harder for truck drivers since they don't have back windows.
Title: Re: Largest signed roundabouts in the US/Canada
Post by: roadfro on April 21, 2014, 06:40:25 AM
Quote from: froggie on April 20, 2014, 08:24:30 PM
Despite signage to the contrary, I'd argue the three Florida circles in the original post are traffic circles and not roundabouts.  Namely, the radius of the circle.  Roundabouts, by design, have fairly tight radii.  These Florida examples do not.

Add to that the inner pavement markings that seem to suggest that lane changes are required to exit from the inside circulating lane. A properly designed roundabout should allow for an eventual exit from the inner lane if you follow the markings.
Title: Re: Largest signed roundabouts in the US/Canada
Post by: AsphaltPlanet on April 21, 2014, 07:52:10 AM
Quote from: mhh on April 20, 2014, 09:21:59 PM
This one in Sterling Heights, Michigan isn't large in diameter but it's large in width; it's three lanes wide!

https://goo.gl/maps/BtSMA

Ontario has a couple of three lane roundabout as well.  The newest is at the bottom end of the 406:

(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fwww.asphaltplanet.ca%2FON%2Fhwy_404-406_images%2F406_rbt_EastMain_east_Mar13_forum.jpg&hash=b82930ab34313fc3ff237ba24870102347aa43d9)

(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fwww.asphaltplanet.ca%2FON%2Fhwy_404-406_images%2F406_cl_25_northwest_Mar13_forum.jpg&hash=f73b6d4d2f0102a983478c9530f06ec0944f1c6a)
Title: Re: Largest signed roundabouts in the US/Canada
Post by: jakeroot on April 21, 2014, 02:15:25 PM
Quote from: roadfro on April 21, 2014, 06:40:25 AM
Quote from: froggie on April 20, 2014, 08:24:30 PM
Despite signage to the contrary, I'd argue the three Florida circles in the original post are traffic circles and not roundabouts.  Namely, the radius of the circle.  Roundabouts, by design, have fairly tight radii.  These Florida examples do not.

Add to that the inner pavement markings that seem to suggest that lane changes are required to exit from the inside circulating lane. A properly designed roundabout should allow for an eventual exit from the inner lane if you follow the markings.

Here is my extremelly rough sketch as to how you could feasibly fix the roundabout. This design would be useful if they didn't want to lower the number of circulating lanes:

(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fi.imgur.com%2FF2DhjRA.png&hash=6761b008749020b686a9e317850ef522e51c570f)
Title: Re: Largest signed roundabouts in the US/Canada
Post by: jeffandnicole on April 21, 2014, 03:26:24 PM
Quote from: Brian556 on April 21, 2014, 02:16:43 AM
Fort Worth, Texas:
https://maps.google.com/?ll=32.717815,-97.442368&spn=0.006328,0.012392&t=h&z=17 (https://maps.google.com/?ll=32.717815,-97.442368&spn=0.006328,0.012392&t=h&z=17)
This one is horribly signed. No roundabout signage; no BGS diagram sign either. US 377 and SH 183 pass through.
The worst thing is that traffic already in the circle has to yield to SB SH 183 traffic entering the circle. It is a very awkward angle to yield at, and it is hard to look at that angle for gaps in traffic. It would be even harder for truck drivers since they don't have back windows.

New Jerseyians would feel at home with a circle like this!  :spin:  Heck, at least that circle has bypass lanes and such.  In NJ, the business driveways provide direct access to & from the circle!
Title: Re: Largest signed roundabouts in the US/Canada
Post by: roadfro on April 23, 2014, 12:42:38 AM
Quote from: jake on April 21, 2014, 02:15:25 PM
Quote from: roadfro on April 21, 2014, 06:40:25 AM
Quote from: froggie on April 20, 2014, 08:24:30 PM
Despite signage to the contrary, I'd argue the three Florida circles in the original post are traffic circles and not roundabouts.  Namely, the radius of the circle.  Roundabouts, by design, have fairly tight radii.  These Florida examples do not.

Add to that the inner pavement markings that seem to suggest that lane changes are required to exit from the inside circulating lane. A properly designed roundabout should allow for an eventual exit from the inner lane if you follow the markings.

Here is my extremelly rough sketch as to how you could feasibly fix the roundabout. This design would be useful if they didn't want to lower the number of circulating lanes:

(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fi.imgur.com%2FF2DhjRA.png&hash=6761b008749020b686a9e317850ef522e51c570f)

You've kind added to the circulating lanes and exiting lanes here, but the concept behind the markings you propose is more akin to a roundabout. The MUTCD has a variety of marking patterns as examples for a variety of situations, including 2-lane roundabouts with 1- or 2-lane exits.
Title: Re: Largest signed roundabouts in the US/Canada
Post by: jakeroot on April 23, 2014, 12:46:05 AM
Quote from: roadfro on April 23, 2014, 12:42:38 AM
the concept behind the markings you propose is more akin to a roundabout.

Isn't that what it is? I don't believe rotaries/traffic circles deserve less attention just because they are big. And yes, I did add a few new lanes to the southern leg. That wasn't intentional.  :-D
Title: Re: Largest signed roundabouts in the US/Canada
Post by: jakeroot on April 23, 2014, 12:49:14 AM
Quote from: AsphaltPlanet on April 21, 2014, 07:52:10 AM
Quote from: mhh on April 20, 2014, 09:21:59 PM
This one in Sterling Heights, Michigan isn't large in diameter but it's large in width; it's three lanes wide!

https://goo.gl/maps/BtSMA

Ontario has a couple of three lane roundabout as well.  The newest is at the bottom end of the 406:

IMAGES (https://www.aaroads.com/forum/index.php?topic=12156.msg293939#msg293939)

I was just reading about that roundabout. It appears, as usual, people are up in arms because they refuse to learn a new technique. You Canadians are better about change than us Americans though.
Title: Re: Largest signed roundabouts in the US/Canada
Post by: roadfro on April 23, 2014, 01:08:52 AM
Quote from: jake on April 23, 2014, 12:46:05 AM
Quote from: roadfro on April 23, 2014, 12:42:38 AM
the concept behind the markings you propose is more akin to a roundabout.

Isn't that what it is? I don't believe rotaries/traffic circles deserve less attention just because they are big. And yes, I did add a few new lanes to the southern leg. That wasn't intentional.  :-D

My original post in this topic was stating that the intersection originally depicted here was more like a rotary than a roundabout, but that your alteration makes it more like a roundabout (or pretty much one).

That second post was meant to point out that this intersection can be striped like a roundabout now, without adding any lanes to any part of the existing roadways. You'd just need to apply appropriate lines, as depicted in the MUTCD.
Title: Re: Largest signed roundabouts in the US/Canada
Post by: jakeroot on April 23, 2014, 01:26:56 AM
Quote from: roadfro on April 23, 2014, 01:08:52 AM
Quote from: jake on April 23, 2014, 12:46:05 AM
Quote from: roadfro on April 23, 2014, 12:42:38 AM
the concept behind the markings you propose is more akin to a roundabout.

Isn't that what it is? I don't believe rotaries/traffic circles deserve less attention just because they are big. And yes, I did add a few new lanes to the southern leg. That wasn't intentional.  :-D

My original post in this topic was stating that the intersection originally depicted here was more like a rotary than a roundabout, but that your alteration makes it more like a roundabout (or pretty much one).

That second post was meant to point out that this intersection can be striped like a roundabout now, without adding any lanes to any part of the existing roadways. You'd just need to apply appropriate lines, as depicted in the MUTCD.

Ah, I see. Maybe next time, I'll learn to read.  :pan:
Title: Re: Largest signed roundabouts in the US/Canada
Post by: jakeroot on September 24, 2020, 03:55:02 PM
Glad to see I already started a topic on this.

Found a couple of absolutely gigantic roundabouts (https://www.google.com/maps/@39.2729387,-94.6591554,993m/data=!3m1!1e3) in KCMO:

They are all signed as roundabouts and use spiral markings. Satellite photo research shows they were modified in late 2011 or early 2012 to become roundabouts with spiral markings, instead of the earlier traffic circles they were originally built as (sometime in the 1980s I believe).

The largest of the two:
(https://live.staticflickr.com/65535/50380057116_26c488386b_o.png)

The "smaller" of the two:
(https://live.staticflickr.com/65535/50380057016_bbb39e91e6_o.png)
Title: Re: Largest signed roundabouts in the US/Canada
Post by: ethanhopkin14 on September 24, 2020, 04:56:17 PM
I would like to see a roundabout that encompasses a small town so that the roundabout is the bypass.  Hahaha!
Title: Re: Largest signed roundabouts in the US/Canada
Post by: hotdogPi on September 24, 2020, 05:06:32 PM
Quote from: ethanhopkin14 on September 24, 2020, 04:56:17 PM
I would like to see a roundabout that encompasses a small town so that the roundabout is the bypass.  Hahaha!

Dothan, AL
Title: Re: Largest signed roundabouts in the US/Canada
Post by: STLmapboy on September 24, 2020, 07:07:39 PM
Quote from: 1 on September 24, 2020, 05:06:32 PM
Quote from: ethanhopkin14 on September 24, 2020, 04:56:17 PM
I would like to see a roundabout that encompasses a small town so that the roundabout is the bypass.  Hahaha!

Dothan, AL
Dothan's has to be one of the tightest, neatest circles I've seen.
Title: Re: Largest signed roundabouts in the US/Canada
Post by: jakeroot on September 24, 2020, 07:44:33 PM
Quote from: STLmapboy on September 24, 2020, 07:07:39 PM
Quote from: 1 on September 24, 2020, 05:06:32 PM
Quote from: ethanhopkin14 on September 24, 2020, 04:56:17 PM
I would like to see a roundabout that encompasses a small town so that the roundabout is the bypass.  Hahaha!

Dothan, AL
Dothan's has to be one of the tightest, neatest circles I've seen.

For what it is, definitely. Most routes of that kind can get pretty jagged.

But as to the road itself: obviously that's just a ring road, not really a roundabout. Even if locals call it the "Circle".

Closest thing you might be looking for, ethanhopkin14, would be one-way motorways like in Osaka, Japan.
Title: Re: Largest signed roundabouts in the US/Canada
Post by: CardInLex on September 24, 2020, 08:33:18 PM
Quote from: STLmapboy on September 24, 2020, 07:07:39 PM
Quote from: 1 on September 24, 2020, 05:06:32 PM
Quote from: ethanhopkin14 on September 24, 2020, 04:56:17 PM
I would like to see a roundabout that encompasses a small town so that the roundabout is the bypass.  Hahaha!

Dothan, AL
Dothan's has to be one of the tightest, neatest circles I've seen.

See: New Circle Road in Lexington, KY
Title: Re: Largest signed roundabouts in the US/Canada
Post by: STLmapboy on September 24, 2020, 09:31:27 PM
Quote from: CardInLex on September 24, 2020, 08:33:18 PM
Quote from: STLmapboy on September 24, 2020, 07:07:39 PM
Quote from: 1 on September 24, 2020, 05:06:32 PM
Quote from: ethanhopkin14 on September 24, 2020, 04:56:17 PM
I would like to see a roundabout that encompasses a small town so that the roundabout is the bypass.  Hahaha!

Dothan, AL
Dothan's has to be one of the tightest, neatest circles I've seen.

See: New Circle Road in Lexington, KY
Guess I just forgot about that one since it's totally been swallowed up by the city.
Title: Re: Largest signed roundabouts in the US/Canada
Post by: Finrod on September 27, 2020, 01:40:49 PM
Newton Grove, North Carolina calls theirs a circle:

https://www.google.com/maps/@35.2454002,-78.3544757,287m/data=!3m1!1e3

There's even a Circle Street that makes a large hexagon around it.
Title: Re: Largest signed roundabouts in the US/Canada
Post by: jakeroot on September 30, 2020, 07:29:05 PM
Quote from: Finrod on September 27, 2020, 01:40:49 PM
Newton Grove, North Carolina calls theirs a circle:

https://www.google.com/maps/@35.2454002,-78.3544757,287m/data=!3m1!1e3

There's even a Circle Street that makes a large hexagon around it.

It does have "roundabout ahead" (W2-6) signs approaching the "circle" (https://goo.gl/maps/dFvNeUgk8dNpPFaC8), so while they call it a circle (as it was built prior to the term "roundabout" becoming a thing), they recognize it, and its operation, more as a roundabout.

Still, cool example. Definitely quite large.
Title: Re: Largest signed roundabouts in the US/Canada
Post by: CoreySamson on September 30, 2020, 11:30:32 PM
Not a roundabout, but it is named a traffic circle, and it is quite large:

Masonic Circle in Alexandria, LA  (https://www.google.com/maps/@31.2740535,-92.4695278,1083m/data=!3m1!1e3)
Title: Re: Largest signed roundabouts in the US/Canada
Post by: jakeroot on October 01, 2020, 01:04:53 AM
Quote from: CoreySamson on September 30, 2020, 11:30:32 PM
Not a roundabout, but it is named a traffic circle, and it is quite large:

Masonic Circle in Alexandria, LA  (https://www.google.com/maps/@31.2740535,-92.4695278,1083m/data=!3m1!1e3)

That may be the largest circular intersection in the US without anything in the middle. Very cool!!!
Title: Re: Largest signed roundabouts in the US/Canada
Post by: MCRoads on October 17, 2020, 11:11:18 PM
Quote from: jakeroot on October 01, 2020, 01:04:53 AM
Quote from: CoreySamson on September 30, 2020, 11:30:32 PM
Not a roundabout, but it is named a traffic circle, and it is quite large:

Masonic Circle in Alexandria, LA  (https://www.google.com/maps/@31.2740535,-92.4695278,1083m/data=!3m1!1e3)

That may be the largest circular intersection in the US without anything in the middle. Very cool!!!

That isn't a circle, that's a rounded square!

Also, anyone got any pictures of NJ rotaries? Are they as bad as the road around Arc De Triumph?
Title: Re: Largest signed roundabouts in the US/Canada
Post by: kphoger on October 20, 2020, 02:20:08 PM
Quote from: MCRoads on October 17, 2020, 11:11:18 PM
Are they as bad as the road around Arc De Triumph?

I think you might have to go to India to find a traffic circle as bad as that.