The Roundabout (Page 2): I figure that I've spent about a year driving in the UK and Ireland. Roundabouts are ubiquitous, ranging from small ones to huge ones at busy interchanges...

therwol Loc: USA

jerryc41 wrote:

What got me to post this is the cartoon that someo... (show quote)

I figure that I've spent about a year driving in the UK and Ireland. Roundabouts are ubiquitous, ranging from small ones to huge ones at busy interchanges, typically where roads feed into a motorway in urban areas. The large ones can be regulated by traffic lights that turn green in sequence around the circle. There can be considerable backup to get into one during rush hour.

The lanes leading up to one can have the desired exit or exits painted on the roadway so that you can be in position for your exit once you enter. There are two problems I encountered with that. If traffic is heavy, the line of cars in front of you obscures those painted directions. Second, they may be absolutely wrong, sending you to the wrong exit or around in circles until you can manage to change lanes, which isn't easy going around in a circle in bumper to bumper traffic. I almost crashed into another car several times.

Ireland had a unique problem. This was before GPS was common. Your desired destination might be indicated in one roundabout, say Dun Laoghaire, you'd take that exit, and it wouldn't be an option at the next one, making you have to stop and pull out a printed map and cross your fingers. I once ended up in the Dublin Town Center trying to get to Dun Laoghaire.

SteveR Loc: Michigan

We had one in Dallas. It was the source of a significant number of accidents, so it was done away with.

RiJoRi Loc: Sandy Ridge, NC

Ollieboy wrote:

Let's not forget the "jughandle" which is very famous in New Jersey. I think it was invented to eliminate left turns and keep the main road narrower since there is no left turning lane.

As an ex-Long Islander, I believe that the jughandles were invented to confuse and/or amuse the rest of the country. How do the unknowing interpret "USE RIGHT LANE FOR LEFT TURN"? 😱 Does that mean I need to cut across several lanes of traffic to make a left?
😁

--Rich

alexol

SteveR wrote:

We had one in Dallas. It was the source of a significant number of accidents, so it was done away with.

Had one what, in Dallas?

RiJoRi Loc: Sandy Ridge, NC

I also see a traffic circle as a modified T intersection on a divided highway. Green arrows show direction of traffic. The two vertical lines are small, 2-way streets. The curvy lines are for making U-turns.

--Rich

DirtFarmer Loc: Escaped from the NYC area, back to MA

RiJoRi wrote:

I also see a traffic circle as a modified T intersection on a divided highway. Green arrows show direction of traffic. The two vertical lines are small, 2-way streets. The curvy lines are for making U-turns.

--Rich

Hope the turnarounds are far apart. Most divided highways are 2 lanes each way so after using the turnaround you have to cross 2 lanes of traffic to get to the cross street. If you want to go from one cross street to the other you have to do that twice.

Flyerace Loc: Mt Pleasant, WI

The Wisconsin Department of Transportation went on a bender a few years ago. They put these things everywhere they could. The big problem, they didn't plan big enough for 18wheelers to make the trip. Every truck ended up with part of his rig near the center, thus stopping everyone until they cleared.

They also put two or three of them together to make it nearly impossible to go from A to B without covering half the alphabet. Everyone was pretty worked up about it.

The DOT then told one group of homeowners, businesses that a round a bout would be going in their intersection. This would take down 3 houses, a gas station and a 50+year old Italian restaurant. The restaurant owner started a petition, that was signed by every single customer that visited. He contacted the Governor (Scott Walker) and hand delivered the petition. He explained about the total chaos that would be visited in this neighborhood. Finally he pointed out that the intersection affected had no history of accidents.

The Governor changed how things were done. He said if people didn't want the round-a-bouts, they could contact his office and the DOT and they would not disrupt their neighborhoods. The construction stopped quickly. Now, it is notified of the intent and the people can comment if they wish.

SteveR Loc: Michigan

alexol wrote:

Had one what, in Dallas?

Take Julie's advice and go back to the very beginning, a very good place to start.

https://www.youtube.com/watch?v=drnBMAEA3AM

RiJoRi Loc: Sandy Ridge, NC

DirtFarmer wrote:

Hope the turnarounds are far apart.

😉 That's why I didn't show any distances! 😁 It's a "perfect model" to be the basis of a "real world" model. As the old saying goes,
"In theory, there's no difference between theory and practice.
In practice, there is." 👍

DirtFarmer wrote:

Most divided highways are 2 lanes each way so after using the turnaround you have to cross 2 lanes of traffic to get to the cross street. If you want to go from one cross street to the other you have to do that twice.

Sure, but this was to show the similarities between the double-T and the traffic circle. Make the divided road into a single road, and squish the turn-arounds together, and you get

 
   |
-——O——
   |

ye olde traffick cirkle! (in ASCII graphics, no less!)

--Rich
P. S., Deauville Boulevard in Copiague, NY, is a divided road, 1 lane each way.

fantom Loc: Colorado

alberio wrote:

Yes, a smaller roundabout takes up less space, but the only way something like this works is much larger, ask the Europeans.

Cheese

jerryc41 wrote:

What got me to post this is the cartoon that someo... (show quote)

Traffic intersections work well when streets are arranged in a grid like NYC. Older European cities, and cities like DC, are often arranged in a spoke-and-hub pattern where multiple streets feed into the roundabout. Roundabouts also speed up traffic flow because there are typically no red lights to hold you up when there is no cross traffic.

Take a look at the roundabout around the Arc de Triomphe. Can you imagine a traffic intersection working here! And for those who think European drivers are more polite, check out the traffic inside the roundabout in the picture!!

(Download)

Laramie Loc: Tempe

In the seven miles between The Village of Oak Creek and Sedona, AZ, the state put in eleven, maybe more, roundabouts. Don't go that way to Sedona on a weekend. They have made it impossible.

Bob Smith Loc: Banjarmasin

A bit too technical for Americans

jerryc41 Loc: Catskill Mts of NY

RiJoRi wrote:

As an ex-Long Islander, I believe that the jughandles were invented to confuse and/or amuse the rest of the country. How do the unknowing interpret "USE RIGHT LANE FOR LEFT TURN"? 😱 Does that mean I need to cut across several lanes of traffic to make a left?
😁

--Rich

Good point.

cbabcock

I remember the Kingston roundabout. The arrow that shows straight ahead or right being permitted looks like it is on a single lane part of the road, the right lane having previously been required to exit.