In Cambridge MA, Rt 2 is a 4 lane limited access 55 MPH highway that comes down a large hill. At the bottom of the hill it dropped from 4 lanes to 2, and then went into a rotary with Rt 16 which caused no end of problems. Many years ago they turned it into a lighted interchange.
Towson, MD.
A couple of years ago, California got its first “turbo roundabout”, at a previously signalized intersection which saw a lot of fatal t-bone collisions. The intersection is heavily used by lots of huge trucks on their way over to Interstate 5 in the central valley.
The roundabout has eliminated fatalities and major t-bones, but has increased minor fender-benders. It’s an initially confusing roundabout, but after you’ve driven through it once or twice it becomes clear how it works. But newbies and inattentive drivers ignore the main trick, which is to know what lane to be in before you approach the roundabout, and then once they’re within the “pinwheel” they try to fix their mistake by changing lanes where they shouldn’t.
This article in a local paper shows a good overhead map of the turbo roundabout.
Last month my wife and I visited a friend who lives on the South Island of New Zealand. While there, he drove us on a tour of the island, where we drove about 1500 miles. Believe me, there are a LOT of roundabouts in NZ, and everybody knows how to navigate them. (Even though they drive on the wrong side of the road…)
One thing he told us is the unwritten rule about signaling when entering a roundabout. If you are exiting on the first exit (a right turn in the US), use your right signal. If you are exiting on the second exit (going straight), don’t signal at all. And, if you are exiting on the third exit (a left turn), use your left signal. Seemed to make sense to me.
But as was mentioned above by @LSLGuy, using one’s signal just before exiting makes sense as well. That’s what I’ve been doing in the past 20 years since two roundabouts were installed at the interstate exits in my small town.
Will your group call it morning driving through the sound and in and out the valley?
Well?
The red light laws in the states I’ve driven in are clear: your sole responsibility is to not enter the intersection on the red. You have no obligation to be out the other side when the opposing direction turns green. If your light is still yellow at the instant your nose crosses the magic line, then you are 100% in the right.
Now the three people who taillgate behind you into the intersection? They are in the wrong and deserve a prompt roadside shooting.
Blocking the box is illegal in nearly all jurisdictions, and in many you are not allowed to be idle in the intersection even on a green.
Good point. Thanks for the improvement.
I was assuming there’s no obstacle to the person who entered on the extreme late yellow getting out the other side at normal driving speed. You’re right there’s more to it: don’t enter unless you reasonably expect to be promptly out the other side.
My larger point was that if you are waiting at a red and as it turns green there are still cars crossing in the intersection, it is not valid to call them red light runners. They might be, but they probably are not. It seemed to me that @Nyvaak was making that wrong assumption.
You may well be right, although if they’re still in the intersection by the time my light turns, there’s a good probability that they are. My main point is that they’re usually not a great hazard. Once the light turns green for me I ought to be able to move, sure, but I don’t have anything like the acceleration to make a collision likely between me and those who were just a tiny bit late in the intersection.
True red-light-runners, as I said originally, are uncommon (thank goodness).
Idiots who fail to yield appropriately in traffic circles are far more common in my experience. Traffic lights are pretty clear cut. Traffic circles rely on the judgment and courtesy of many drivers. A recipe for frustration at the very least.
Quite.
The latest fad in this part of England is the hamburger roundabout. They can be a bit confusing for people not used to them. Normally at a roundabout, if you wanted to turn right, you’d be in the right hand lane. But with these, you need to be in the left hand lane. I encountered one in Nottingham a few years ago, and now they’ve spread to my home county of Essex.
No, no, it’s a debate group, we get into circular arguments…
Ref Wickenburg AZ upthread. Here’s Cordes Junction AZ:
If you zoom in appropriately you’ll notice two artful traffic circles at the highway on- & off-ramps.
Only problem was they made them smaller than can be negotiated by 18-wheelers. Who are the predominant users of those exits. The townlet’s population is nothing compared to the transient traffic visiting the truck stops. Which results in high-centered truck/trailer combos blocking the circles rather often. If the northern one gets blocked, no one can enter or leave the town on Hwy 69. There are no other routes to it.
In some of those with lights, the signals are only on during rush hour. They revert to ordinary roundabouts at other times. Of course rush hour may be 5 hours long …
Thanks.
Hey! Isn’t that Jane the Cane’s old haunt? If so, no wonder she welcomed the move to West Virginia.
Which I would argue is a worthwhile tradeoff.
Let me summarize a few points that have been covered/linked, but I think are worth reiterating.
First, I understand that “yield to the right” was one of the OG rules of the road, but we’re talking like pre-WWII when they were first figuring all this out and porting over rules from horses and buggies. It’s gradually been whittled away as we’ve learned that it actually sucks as an across-the-board rule for motor vehicles and modern road design. It still applies to uncontrolled intersections, and to 4-way stops where two vehicles arrive at the same time. It works there because it clears the intersection faster (the vehicle on the right only has to get halfway across the intersection before the vehicle on the left can go, whereas if the vehicle on the left goes first then it has to clear the entire intersection before the vehicle on the right can go). Where yield to the right doesn’t work is for highway ramps, slip lanes, general lane changing, T-intersections, and rotaries/traffic circles/roundabouts. It should not apply to the latter because at any amount of traffic volume will lock up the circle since entering traffic has right-of-way over circulating/exiting traffic.
So that brings us to the old style rotaries and traffic circles that are prevalent in New England especially. Those often have poor geometry/visibility, they were originally built for yield-to-right, and the circle is often way too large leading to high circulating speeds. The geometric qualities are difficult to retrofit without a full rebuild, but at the very least the yield rules can be fixed to keep it from locking up. Roundabouts on the other hand (or modern roundabouts built after 1990 in the US if you want to be extra pedantic) have very specific geometric design constraints and signage best practices to make them safe and functional.
Sometimes you do see “neighborhood roundabouts” which are minimal constructions within an existing 4-way intersection that is otherwise unmodified. They may have just a painted circle, a planter bed, or a small raised platform that can be driven over (especially when turning left) but is enough of a bump to make most drivers deflect around it if possible and slow down. That is mostly a traffic calming device.
Many town squares in the US have also had their corners rounded off to turn them into something more like a roundabout, though often to the detriment of the square itself as a public space. Carthage, NC is one example where they just rounded off the inner courthouse square without doing any other design work. In Troy, OH they went all-in on reengineering it for traffic purposes, but now it’s only a place for cars and nothing else. Pittsboro, NC is something in between. It’s a mostly engineered roundabout, but the courthouse still lives in the middle. All of these were square squares originally though.
I’m mostly all-in on roundabouts being positive, and older style rotaries and traffic circles should be reengineered as much as possible to modern standards. The primary issue I see is just “old man yells at cloud” pearl clutching. Also (we) Americans are idiots in general and don’t understand yielding. Most people seem to think it means “bludgeon your way into traffic and good luck everybody else” instead of “stop for traffic that has the right-of-way.”
I also think that while they are better for traffic flow and traffic calming, and they are better for preventing serious or fatal collisions, any increase in fender benders causes people’s car brain to short-circuit. Whether they’re better for pedestrians and cyclists is much less certain, and they may even be somewhat worse because it requires vehicles to yield to them, and like I just said yielding is for some reason incomprehensible to a lot of people, especially when it comes to crosswalks and bicycles.
One interesting issue roundabouts can cause when you have a lot of them is that the continuous flow of traffic can make it more difficult for side street and driveway traffic to get onto the roads because of a lack of gaps. Traffic signals create platoons of impenetrable traffic, but they also leave gaps that can be useful especially for left turning or crossing vehicles and pedestrians at the minor intersections in between. I don’t know if there’s much data on this though.
:: chortle ::
Okay, explain NJ traffic rules (sorry, trick question, that’s impossible!); three of four circles that I can think of there have the major road having right of way & traffic already in the circle yielding to the entering traffic. If (at least) one state does it differently, & only some of the time how the 'ell is someone supposed to know what rules to follow?
-* three of those four are on one road, about a mile between all three of them, in order they are:
- Traffic in circle yields
- Traffic entering circle yields
- Traffic in circle yields
While driving on right-left combo of turns, one is not only looking for any car in your blind spot but where you want to be, divining where the other cars may want to be as well as cars that may be entering, while simultaneously looking to see if you have the yield or the entering car does.
These are older traffic circles, predating the invention of the modern roundabout. They haven’t been modernized (yet). New Jersey and New England, especially Massachusetts, had more of them than other states, although there were some elsewhere.
Note that the Yield sign was only invented around 1950, so traffic engineers before that time didn’t have a mechanism to override the yield-to-the-right default rule of traffic. Not that they used it for that purpose very much. Once they had that tool, many early traffic circles were optimized for traffic between two specific legs and all the others and vehicles within the circle had to yield or stop for that traffic.
There should be a yield sign either facing the entering road or facing the circle, even better some pavement markings too.