Modern Roundabout!
Modern Roundabout, Freiberg, Germany
I’ve written before of my love for “modern roundabouts”—the thinking man’s alternative to the dread traffic circle—but this was largely a theoretical proposition since we don’t have very many in the United States. So I was very excited when our bus drove around one in Freiberg.
The basic underlying idea is that instead of trying to use signals to create a false sense of security in an inherently dangerous situation, you need to design the road so as to psychologically demonstrate to everyone the need to drive in a calm, careful, and relatively slow manner. With everyone moving a bit slower, traffic as a whole can still proceed at a reasonable speed and you sharply reduce the kind of accidents that both kill people and produce severe congestion.
60 Responses to “Modern Roundabout!”
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September 21st, 2009 at 1:32 pm
Well, that’s true, but another main point of a roundabout is to eliminate 4-way intersections in favor of simple 3-way intersetions with at least one of the 3 roads a one way street. That simplifies the traffic patterns a lot.
September 21st, 2009 at 1:37 pm
The roundabouts I’ve ridden on in Europe must not be the newfangled “modern” type, cuz the traffic on the ones I’ve seen is crazy, something like a scene from Monty Python’s Twit of the Year contest.
DC’s traffic circles certainly are no advertisement for the set-up — anything that could improve those would be good.
September 21st, 2009 at 1:39 pm
Traffic in Shanghai was unbelievable. It was slow but the key thing is that for the most part everyone yielded. The obverse is that most everyone was not an aggressive jerk. I was in one cab and he wanted to be the aggressive jerk. He insisted on trying to get ahead of a bus as our left hand lane was ending and the bus banged the right rear quarter.
September 21st, 2009 at 1:40 pm
some reading for while you’re away
September 21st, 2009 at 1:50 pm
Building on this, why not change the majority of stop signs to yield signs? If there’s someone else in the intersection before you, you yield to him. If not, you slow down and continue moving. We would save a lot of gasoline, a lot of time, and a lot of carbon emissions. And I don’t think it would be all that dangerous.
September 21st, 2009 at 1:51 pm
As I commented following Matt’s previous roundabout post, we love the single-lane roundabout that was installed to replace a 4-way stop adjacent to our subdivision last year. It has delivered in every way promised: less rush-hour congestion, fewer accidents, and less severe accidents. Some people still treat the yield signs as stop signs, and a few have utterly ignored me while I was in the roundabout, but those are mere frustrations.
September 21st, 2009 at 1:52 pm
I don’t know that I get what makes that roundabout different from any other that I’ve seen?
Generally I think roundabouts are vastly superior if the traffic level’s right. In practice, people are so poorly educated about their proper use that it leads to disaster in the States when sparsely implemented. No clue how it’s all that hard to grasp the only applicable rule – if you’re in the circle, you have the right of way – but that’s how it is.
What’s infuriating is suburbs implementing micro roundabouts (I’ve even seen chicanes; it’s incredible) for the purpose of slowing down irresponsible teenagers.
September 21st, 2009 at 2:01 pm
Wow, a roundabout… That’s so … unremarkable… Yawn…
September 21st, 2009 at 2:06 pm
“If you’re in the circle, you have the right of way” conflicts with the other, better-known yield rule: when two people arrive at an intersection at the same time, the one on the right has the right-of-way.
In Massachusetts, what one did was left up to individual towns, so no one knew what the right thing to do. Finally, a state law was passed, and signs were posted on all the rotaries (roundabouts).
I think about roundabouts whenever I am forced to sit at an otherwise empty intersection and wait for a red light to change.
Roundabouts/rotaries take up more space than a straightforward intersection, however.
September 21st, 2009 at 2:06 pm
It’s not been my experience, and it seems rather unpleasant, but OK. If that’s what the studies say, that’s what the studies say.
September 21st, 2009 at 2:11 pm
I once had occasion to drive around a bit in England in a left hand drive vehicle. The round a bouts seemed especially whirly in that circumstance for some reason
September 21st, 2009 at 2:15 pm
I wouldn’t generalize too much about Chinese drivers based on rapier’s description of traffic in Shanghai. I spent a year in Taiwan and the roads there were absolutely dominated by aggressive jerks. To take just one example: taxies, when approaching a traffic light, would routinely cut into the oncoming lane even on very busy 4-lane urban roads.
When I was shopping for a motorcycle, the one thing that was non-negotiable was that the horn had to work. Driving on a motorcycle in Taiwan without a horn would get you killed. At night you had to hit the horn as you approached each and every intersection because otherwise you were likely to get hit by someone running a red light. It was nuts.
This was in the early 90s. It’s possible things have changed since then.
September 21st, 2009 at 2:17 pm
In practice, people are so poorly educated about their proper use that it leads to disaster in the States when sparsely implemented.
There’s definitely a degree of bootstrapping required, and signage can play it’s part. And the ones built recently near me have plain concrete for the centre circle, when I think it’s smarter to have greenery, as is common in most places that use them, and as seen in the photo. That’s part of the psychology, to make the point that it ain’t part of the road. (I remember seeing cows grazing on them in New Delhi.)
But, seriously, it’s not like learning to drive a grand prix car. I’ve been alongside American drivers in Europe who went from being intimidated by the things to mastering them in the space of a single trip.
September 21st, 2009 at 2:21 pm
We don’t have many in the United States? You went to school in Massachusetts, for god’s sakes!
And they’re called rotaries
September 21st, 2009 at 2:22 pm
What this really proves is just how poorly Matt knows his own back yard. Had he traveled, oh, 30 miles north of his own home, to Howard County Maryland, he’d see lots of traffic circles. Still too many lights as far as I’m concerned, but still.
It’s this kind of “authoritative” reporting that tells me that Matt is really an expert on everything that’s within about 2 blocks of his DC apartment. Beyond that, his map of the US must read “there be dragons”…
September 21st, 2009 at 2:22 pm
The UK has always relied heavily on them and take them for granted. They don’t work so well with heavy traffic, but that is easy enough to solve: revert to controlling the junction with traffic lights in rush hour.
September 21st, 2009 at 2:23 pm
We have a string of roundabouts (5 of em) along a fairly busy suburban road, and as far as I can tell, they work great. Compared to the normal “shit-can it to 50 for 1/4 mile, stop at red light, shit-can it to 50 for 1/4 mile, stop at red light, shit-can it to 50… etc” suburban drive, I much prefer them.
I’d guess that they work well when you have a main thoroughfare with small intersecting residential streets or restraunt/strip mall parking lots, and not a lot of pedestrian traffic. I could see having two busy, big intersecting streets in a roundabout causing more trouble though.
September 21st, 2009 at 2:23 pm
@pseudonymous in nc
I agree that it’s not that hard and that good signage helps. There’s one in a high-traffic (pedestrian and vehicular) intersection in Towson, MD that’s well-signed and, despite being a pretty complex traffic pattern, works alright – http://marylandonmymind.wordpress.com/2009/03/28/towson-roundabout/ – the only problem there is that drivers get confused and ignore the pedestrian crosswalks, but that’s part of a broader failure to communicate to Maryland drivers that pedestrians have the right of way in marked crosswalks. The Towson roundabout only really works because traffic is usually so slow that people have time to read the rules, though.
September 21st, 2009 at 2:25 pm
Had a roundabout in my hometown. My brother and his crazed high school friends held the record, 115 continuous circuits in one day!
September 21st, 2009 at 2:25 pm
@James
Given that there’s a handful of well known traffic circles and a few smaller roundabouts in DC, I don’t get what you’re complaining about. I’ve sat at thousands of lights that’d be better served by roundabouts in my lifetime… it’s not that they don’t exist, just that there aren’t enough of them.
September 21st, 2009 at 2:25 pm
Roundabouts may be better for cars, but they are much worse for pedestrians (in part because of the fact touched on by dm@9 – they take up more space).
September 21st, 2009 at 2:29 pm
Works fine @ Chevy Chase circle…
September 21st, 2009 at 2:31 pm
Building on this, why not change the majority of stop signs to yield signs? If there’s someone else in the intersection before you, you yield to him. If not, you slow down and continue moving. We would save a lot of gasoline, a lot of time, and a lot of carbon emissions. And I don’t think it would be all that dangerous.
Right, but then what would anti-cyclists yahoos complain about? Your idea is just cruel.
September 21st, 2009 at 2:33 pm
I’m all for fewer electronic traffic signals; I agree with this post. However, roundabout vs traffic circle is just what they are called regionally. Not all traffic circles have stoplights.
I was driving through Upperville on US 50 recently I noticed some traffic calming measures in place (medians and raised crosswalks).
It’s not just driving in cities and towns; I think people aren’t calm enough on highways. If people would just leave a safe following distance, they wouldn’t need to hit the brake so much when in turn causes more braking behind them.
September 21st, 2009 at 2:35 pm
Roundabouts may be better for cars, but they are much worse for pedestrians
That’s not really true if they’re done properly. The DOT specification show the importance of traffic islands where pedestrians can stop in the middle of the road. Roundabouts also generally allow narrower roads, because you don’t need separate lanes for left turns, which makes crossing easier.
As I’ve mentioned before, I’ve lived near six- or eight-lane drags where there’s no pedestrian crossing phase to the signalling, which means that getting from one side to the other becomes a chicken run for pedestrians.
September 21st, 2009 at 2:40 pm
#20 – my point is, there’s a growing trend toward building roundabouts in the US. Matt seems utterly oblivious to that, but given his hatred of all things non-mass-transit, that’s not a huge surprise.
September 21st, 2009 at 2:58 pm
Why does this rational driver argument make me think of the faith-based efficient market theory that serves us so well?
September 21st, 2009 at 3:04 pm
It isn’t just psychological; look at that road as it enters the circle. Look at the radius of the corner. It’s like a T-intersection, and anyone entering the circle has to come very close to stopping in order to make the turn.
But traffic circles, except the very smallest ones (the ones, like in Seattle, where they put a small circle in the middle of an intersections and don’t change the curbing at all), are just no good for pedestrians.
September 21st, 2009 at 3:14 pm
No, there’s a difference. It’s called “deflection” – the angle of the turn a driver approaching the traffic circle must make to enter it.
Rotaries were designed so that a car approaching the circle didn’t have to slow down, or hardly slow down, to enter, traverse, and exit the circle. The roadway approaching a rotary splits well before it gets to the circumference, and becomes a gradual curve, like taking an exit ramp off a highway. Picture a rotary as being like a clock. If you are approaching at the 6, you gradually drift right, and you enter almost at the 4, already turned about 70 degrees from your original angle. The act of entering the flow of traffic is like merging onto a highway from a ramp; the cars in the circle are coming up from behind you, rather than perpendicular to you. Then, the exit you take to go out at the 12 of the clock is about at the 2, and is once again like an exit ramp.
Roundabouts, on the other hand, are designed so that you have to slow way down to enter. The approaching road has little or no deflection, so that you actually have to take a right turn of almost 90 degrees to enter and exit the circle. Believe me, when you’re just about stopped, and the traffic ahead of you is zipping along at 20-30; and when you need to make a turn into the circle, while the cars in the circle are passing in front of you as if you are stopped at a light and the cross-street traffic is moving, it’s pretty easy to figure out who is supposed to yield.
September 21st, 2009 at 3:16 pm
Why is that tree wearing a metallic breastplate? It it performing in a Wagner festival? Is that a reflector to deter drivers who might otherwise slam into it at night?
September 21st, 2009 at 3:17 pm
What this really proves is just how poorly Matt knows his own back yard. Had he traveled, oh, 30 miles north of his own home, to Howard County Maryland, he’d see lots of traffic circles.
No, what this really proves is that Robertson doesn’t know the difference between a modern roundabout and a traffic circle.
September 21st, 2009 at 3:17 pm
Matt.
Traffic circles (small. slow) at uncontrolled side-street intersections as part of traffic calming
versus
traffic circles as a way to control otherwise stopped-signed or lighted intersections (larger. faster) are different things.
Yes there is overlap but they stem from different circumstances and goals.
But otherwise your emphasis on psychology is quite correct.
September 21st, 2009 at 3:17 pm
Matt.
Traffic circles (small. slow) at uncontrolled side-street intersections as part of traffic calming
versus
traffic circles as a way to control otherwise stopped-signed or lighted intersections (larger. faster) are different things.
Yes there is overlap but they stem from different circumstances and goals.
But otherwise your emphasis on psychology is quite correct.
September 21st, 2009 at 3:21 pm
It’s because you were north of the equator.
September 21st, 2009 at 3:31 pm
September 21st, 2009 at 3:38 pm
They are proliferating here in the Denver area. They mostly suck because people don’t know how/refuse to learn how to drive through them. People are very clear on the stop sign/stop light rules, and we don’t have problems with people running lights like some areas do. But when you go into a roundabout here you take your life in your hands because you never know what the other drivers are going to do.
September 21st, 2009 at 3:48 pm
It’s really not that hard; you just put a Yield sign at each entrance, and maybe Yield Ahead signs a couple hundred feet back.
September 21st, 2009 at 3:51 pm
Sedona, Arizona has some of the most beautiful roundabouts you will see anywhere.
In the Village of Oak Creek section of Sedona (population 5000), a recent improvement project has replaced every single traffic light with roundabout. The result is fantastic and really adds to the beauty of the place.
September 21st, 2009 at 3:55 pm
joe from Lowell Says:
September 21st, 2009 at 3:48 pm
It’s really not that hard; you just put a Yield sign at each entrance, and maybe Yield Ahead signs a couple hundred feet back.
======================================================
Oh, we’ve got those. Doesn’t seem to matter
September 21st, 2009 at 4:07 pm
My only regret in life is that I did not become a roundabout designer. They are coolest things ever. Of course, when I growing up, they, the evil powers that be, did not offer Roundabout Studies.
The only way you could be anti-roundabout is if you enjoy staring at red lights. If that’s your thing, staring at a red light when you are at a dead stop, then that is your thing. I won’t argue.
September 21st, 2009 at 4:20 pm
These roundabouts are a great way to cut down on traffic issues, but I don’t think they can completely replace traffic lights.
September 21st, 2009 at 4:47 pm
Winooski (near Burlington Vermont) installed a big roundabout and it’s been great.
You can see it here:
http://www.youtube.com/watch?v=40gbqXE80VE
September 21st, 2009 at 4:52 pm
Give it six months. People aren’t used to them. There were similar problems when the on-ramp was introduced.
September 21st, 2009 at 4:59 pm
You want roundabouts, come visit Indianapolis’s north suburb of Carmel. They’re even having a roundabout conference.
September 21st, 2009 at 5:01 pm
joe from Lowell Says:
September 21st, 2009 at 4:52 pm
Oh, we’ve got those. Doesn’t seem to matter
Give it six months. People aren’t used to them. There were similar problems when the on-ramp was introduced.
=================================================
Seriously, I’m sorry to say that this doesn’t reflect well on Colorado drivers, but I know a couple of roundabouts here that have been in place for a couple of years and it doesn’t seem to matter.
In a previous job I used to visit the Boston area frequently, and am familiar with the rotaries there. I used to be a little paranoid about those (and had a couple of close calls) because Boston drivers are extremely aggressive.
Here people aren’t aggressive drivers, they just seem clueless. FWIW we had some in a town in California where we used to live, and people there couldn’t seem to figure them out either.
I cringe when I go through them now, because half the time people just ignore the yield signs.
September 21st, 2009 at 5:46 pm
Campy,
Another problem is that they are still rare enough that people who move to or visit a new area are often encountering them for the first time.
September 21st, 2009 at 5:51 pm
Roundabouts are for pussies. What we need are these.
September 21st, 2009 at 6:05 pm
It’s worth repeating that traffic circles and rotaries and “modern roundabouts” are not the same. One of the biggest obstacles to acceptance of modern roundabouts is that people are confused about what they are and have had experiences with poorly-designed traffic circles and rotaries.
The link above provided by jimBob is worth reading. There is a really good website out there somewhere by a civil engineering firm that designs modern roundabouts—I can’t recall it, but it’s worth looking for.
I drive very little and don’t bike and certainly don’t walk around neighborhoods (I’m disabled with a mobility impairment) and so I really have little personal interest in all these transportation issues and definitely have no strong emotional investment in all this stuff which tends to cause people to be passionate and angry. Also, where I live, there are no roundabouts or traffic circles or anything of the kind, anywhere. So I hope that my endorsement of the wisdom of the “modern roundabout” (which is a result of merely reading about them and discovering their benefits as proven by lots of research) will mean something to those on the fence.
September 21st, 2009 at 6:26 pm
I hate the traffic circle I have to go through every day.
It has a weird entrance that allows vehicles leaving a commercial development to enter the circle by cutting in front of the normal entrance/exit on the south side of the circle at a ninety degree angle. The rest of the circle works just fine but this fifth entrance is dangerous and unnecessary since the commercial development already has one regular entrance/exit on the west side of the circle.
September 21st, 2009 at 6:48 pm
The problem with roundabouts is that with a standard traffic light, no matter how heavy the traffic is, you will eventually get your turn to go. But when the traffic gets to a certain density, side roads entering a roundabout can be completely blocked off for an hour or more.
September 21st, 2009 at 6:57 pm
joe from Lowell Says:
September 21st, 2009 at 5:46 pm
Campy,
Another problem is that they are still rare enough that people who move to or visit a new area are often encountering them for the first time.
=========================================================
I much agree – there aren’t enough for people to get used to them
September 21st, 2009 at 7:10 pm
With everyone moving a bit slower, traffic as a whole can still proceed at a reasonable speed and you sharply reduce the kind of accidents that both kill people and produce severe congestion.
I believe someday all cars will be required to have powerful processors that will communicate and interact with centralized sensors, computers, satellites — and other cars — in order to permit the type of situation Matt describes on a universal basis. In essence, cars will drive themselves (or more properly, the network will drive your car) and so optimal speed will be maintained, and crashes and traffic jams virtually eliminated. You may not hit 75mph on the interstate headed into work in the morning. You may not get above 50mph. But the absence of traffic jams means you’ll average say, a pretty steady 45mph — and get to work more quickly than in the pre-netwok days when traffic jams reduced your average speed down to 30mph.
September 21st, 2009 at 7:16 pm
Sounds insanely safe, but Italy provides a counterexample. Roundabouts and safety are independent.
September 21st, 2009 at 7:35 pm
There is an upper-limit on what roundabouts can handle. Beyond that, you’d have to put in an old-fashioned, multi-lane rotary to process that much traffic.
Roundabouts are not not intended for truly massive traffic volumes. They’re a tool, not a magic bullet.
September 21st, 2009 at 10:27 pm
One of the reason that roundabouts work particularly well in the UK is that they drive on the left but also the law is to yield to traffic coming from the right like in this country. Therefore you naturally yield to traffic already in the roundabout. Here we drive on the right but also yield to the right which always leads to confusion, especially if the roundabout is not clearly signposted. I would change the law to make here so that the ‘default’ position in countries driving on the right is to yield to traffic on the left.
September 22nd, 2009 at 9:21 am
http://www.amazon.co.uk/Roundabouts-Great-Britain-Kevin-Beresford/dp/1843308541/r
September 22nd, 2009 at 11:51 am
People were freaked out when the city was planning this rounda about here in Indiana:
http://www.k-state.edu/roundabouts/ada/photos/bloomington.htm
The intersection prior to this was always backed up eight to ten cars deep, now it’s never backed up. Everyone loves it. We’ve built two more in other sections of the city and others are planned. Once people got used to it, it becomes a no-brainer. The intersection definitely has to be appropriate for it though. No more than three busy inputs – ideally two busy inputs – and having more than four total inputs is asking for trouble unless the roundabout becomes excessively large.
September 22nd, 2009 at 10:33 pm
Lots of roundabouts in Australia and I’m not a fan. Within the Australian rules at least, pedestrians have absolutely no rights at a roundabout. By contrast, they have significant rights at giveway signs and stop signs (not that car drivers tend to obey these rules on giving way to pedestrians, nor do the police and road traffic authorities seem to even try to enforce them.) The Australian rules for roundabouts that I dug up went for pages and included detailed discussion of who had right of way when you were riding a horse… but absolutely no mention of pedestrians at all.
September 22nd, 2009 at 11:27 pm
While they might not be classified as modern roundabouts, I can think of some Massachusetts rotaries that approach the design; they tend to be the ones that work best, too.
The worst ones tend to be damaged somehow, by the addition of signals or through lanes or extra ramps to try (generally unsuccessfully) to accommodate higher traffic or new roads. Timothy J. Mahoney Circle in Revere is probably the worst one I can think of; there are two major roads that share the same pair of on- and off-ramps, so that to go from one to the other, you drive all the way around the rotary as if you were making a 180 and then weave around on the short multilane offramp. On top of that, it’s got a signal-controlled lane cutting straight through it, and the signs are tiny and well-hidden. It’s a horror. Definitely not a modern roundabout.
Some other really problematic ones are the little rotaries that meet high-traffic roads tangentially with almost no deflection; incoming drivers think they’re in a through lane and just will not yield to traffic in the rotary, regardless of the law. But others don’t have this problem, and have high enough deflection that they generally work properly. Just in Arlington, Mass. around Mystic Valley Parkway there are examples of both types.
September 26th, 2009 at 8:41 pm
I’m writing this from Austria and our town has three excellently deployed roundabouts, and I love them. But not everyone does.
Here’s a pretty passionate and well-argued case against roundabouts, by a minor league baseball player no less:
http://discohayes.mlblogs.com/archives/2009/08/fan_mail_friday_august_28th.html