We're excited about our new roundabout
wsdotblog.blogspot.com
wsdotblog.blogspot.com
Where I grew up in a rural part of the US, we had one terrible 4-way intersection between two undevided highways. Over time they added lights, then experimented with different signaling systems, but every day it would back up for several miles in a couple directions, and add up to 30 minutes to some commutes. Then there were the inevitable accidents as people tried to rush it, making things worse all around.
They replaced it with a roundabout about a decade ago, the population in the area also has increased dramatically in those years as farms turned into suburbs, but the backup is entirely gone. Theres no need any longer to maintain lights and switching systems, and the accidents are almost nil. Nobody has died there in years. People complained at first because it was "weird" then they realized they were complaining at home a half hour ealier than they would have been, so they stopped.
They've since added a few more in the area and have even gotten very experimental with a double diamond interchange that's also done a lot of good. There's something in the water at the planners office. Seeing that transformation though and the immediate benefits has turned me into a lifetime fan of the roundabout.
Where I live some of the locals treat a newly-built roundabout like the Daytona Speedway. It's almost as if their mentality is that you must NOT slow down, and they won't hesitate to express their displeasure at you if you happen to be "in their way" going the 15mph speed limit through the roundabout.
About 5 years ago my wife an I were doing a California road trip. At one point on a relatively rural road -- I think it might have been Dry Creek road heading into Napa but cannae mind exactly -- we got stuck in traffic for around 45 minutes. We thought there must have been some huge accident or roadworks closing the road. But got the the end and nope... 4 way stop essentially letting one. car. through. at. a. time.
I distinctly remember exclaiming "why the f wasn't that a roundabout" after clearing. Funny that it is now one of my strongest memories of that trip haha.
I think one of the reasons a 4-way stop might be introduced is to improve safety where there was previously a 2-way stop (that people would blow through). I came across this in Canada recently. All I can say is the UK has drastically lower traffic-related deaths than Canada [0] and I think I've seen 2-3 stop signs in my entire life. I imagine North America's pedestrian hostility is a piece of this puzzle.
Don't get me started on North American highway interchanges. The UK's roundabout junction system is far superior, in my opinion.
[0]: https://en.wikipedia.org/wiki/List_of_countries_by_traffic-r...
Four way stops are also common when two country roads of relatively equal weight intersect. There are so many roads like that, so many intersections, that the local government can't possibly afford lights or circles on all of them. If one of the roads is known to get substantially more traffic than the other than a two-way stop is usually used, but if it isn't obvious then a four way stop is the safe default. In these situations, pedestrians aren't a factor at all because the intersection is five miles away from a town and it's farmland on both sides of both roads. Virtually nobody is walking there, not even people walking their dogs (unpaved access roads are better for that anyway.)
In Europe one road (perhaps arbitrarily) would be declared the main road, and the other road gets yield signs, or even just yield road markings (triangles).
The European way requires half as many signposts, and at most half as much stopping and starting of cars.
Throwing a red octagon at every single intersection of two roads is lazy and absurd. It encourages people to break the rules (just run the stop sign) and cause accidents (zone out, stop and go without actually looking).
When turning right, I and a lot of people barely bother slowing down. It's always a bit frustrating when someone does what the sign (and the law of course) says when the don't need too from a pragmatic point of view :-D.
That said, if there's a huge bias towards cars coming from one direction (or out one direction), that can be very difficult to cross. And it has impacts on the roundabout's throughput too, and means that a roundabout might not be the most ideal. Similarly to how a roundabout that gets backedup into can fail catastrophically (you have to make sure there's negative pressure!)
For these use cases there's the turbo roundabout[0]. Depending on how you design it you can give certain directions slightly more priority, though they don't solve the pedestrian issue either.
[0]https://en.wikipedia.org/wiki/Roundabout#Turbo_roundabouts
They make slow or medium traffic flow smoothly. If the traffic is heavy, roundabouts make everything worst.
The West connection is to/from highway, so it has most traffic. People arriving from North/East/South want to leave on the West. And this causes massive jams, as the constant supply of traffic going from South entry to the West exit (i.e. doing left turn, and passing all ramps) essentially blocks all the other traffic.
Roundabout are great, they increase safety of dangerous intersections. But sometimes a controlled intersection is just a better idea.
What usually happens is the roundabout gets traffic lights.
1. https://en.wikipedia.org/wiki/Magic_Roundabout_(Hemel_Hempst...
Indeed, the junction in the headlined article is a slight variation on a quite common U.K. junction type: the double mini-roundabout. We can point to loads of them, such as this one in Bridgeyate (https://www.openstreetmap.org/#map=19/51.457696/-2.462268) for just one random example.
All of the WSDOT's points, about how large vehicles traverse them and how they are shaped like that because the staggered junction or slightly askew cross-roads that they replaced has space restrictions, apply to double mini-roundabouts.
And as bane said, the research in the U.K. back in the 1970s when double mini-roundabouts were a new thing showed a significant reduction in accidents over the prior staggered junctions and askew crossroads, at less cost than enlarging the junctions.
So the response is not to perplex the United Statians with Hemel Hempstead, but to welcome them to the shiny new future of 1970s road systems. And perhaps warn them that by the 1990s the road markings will have become a bit worn and scuffed by all of the HGVs driving over the centre. (-:
With a roundabout, you only have to look in one direction, and if it’s clear, you don’t even have to stop.
IMO all smaller 4 way stops should become what I've described as trash can roundabouts. Small island to circle around. So much better than stop signs.
And it rarely snows in the UK these days. And I would hope you would be driving extremely cautiously if there were snow on the ground (in the UK) as it's such a rare event.
Roundabouts are engrained into UK road culture, you'd seldom find a driver in the UK that cant figure out how one works, even if they may not have great lane discipline on the larger ones.
Too many people remain at the stop sign until the roundabout completely clears, so it becomes an excruciatingly slow 4-way stop. And there's not much traffic there.
A few miles from that one, there's a high traffic roundabout that works very well. The heavily used right turn lanes are divided and don't enter the roundabout. There are very clear markings on the ground. And there are yield signs at the entrances, so people know what to do. Traffic flows great through it, with the heaviest direction of travel naturally getting more throughput.
https://www.google.com/maps/@37.7004641,-120.976448,3a,75y,1...
So, if you were making a sarcastic joke: then yup, they managed to convert a round about into a 4-way stop with a (giant, view obstructing) island. But if you were arguing that no one would do such a thing as put stop signs at the entrances to a round about, I regret to inform you that they absolutely would.
Also, I'm now curious about the existence of "4-way stop with an island". Why would someone build that? It seems strictly worse than a regular 4 way stop.
Your state is doing it wrong then. Almost every four way stop I've ever seen in the US has a little sign beneath the big octagon which says "4-way".
Anyways, I have nothing against roundabouts. But I do have issue with some states (looking at you, Wisconsin) which are obsessed with tearing out perfectly good stop signs (as in, it's a low volume intersection or it's only a two way stop with a highway going through) and replacing them with roundabouts. It's just a waste of taxpayer money.
That being said that looks like a pretty decent and standard setup for a set of roundabouts, certainly wouldn't look out of place in the UK and would be vastly superior to a whole host of stop signs and red lights. It probably could've been simplified slightly by turning the two middle ones into one long oval roundabout, those are pretty common on motorway junctions in the UK.
The Beaconsfield junction on the M40 is a randomly selected example of this very setup in the U.K.: https://www.openstreetmap.org/#map=16/51.59432/-0.62779
Or the junction of the A5 and the A442 in Telford: https://www.openstreetmap.org/#map=16/52.67883/-2.43871
I see people complain about roundabouts with traffics lights and how it negates some of the reasons for the roundabout. The thing is, these aren’t just put in for fun, usually they’re in areas with extremely heavy traffic where merging can get extremely difficult which leads to long backups (or in cities, accidents that can shut down traffic).
Roundabouts can be great when used well, but they’re hardly the silver bullet that online discourse often portrays them as.
I like them, but it is a mistake to blindly install them anywhere possible.
When Cycling and approaching a roundabout move to the middle of the lane and follow the same routes as a car. Yes you slow the cars a bit but they are supposed to be going slowly anyway. If you don't want to do that, you can get off your bike and cross as a pedestrian would.
Maybe you haven't seen the worst ones, then. For instance, one by my house had traffic lines which gave people the wrong impression about the right of way within the roundabout, leading to every vehicle treating driving like that. I actually drove like that as well for a long time - when you're spending every day driving the exact same way that the hundreds of other cars surrounding you are driving, and the lines on the road suggest that it's correct way to drive, it's easy to mistakenly think this is what you're supposed to be doing.
Then it hit me one day - this isn't how right of way works in a roundabout at all. I talked to others in the area, who were surprised when I brought it up. That's what the lines implied, that's what everyone _did_, but that's not how it was supposed to be used. Everyone was driving through this incorrectly. And it was a major roundabout, that had some of the heaviest traffic in the city.
Maybe it didn't matter because everyone was driving incorrectly, which worked most (but not all) of the time? But when it wouldn't, the accident would be a T-bone, so we can't say that roundabouts eliminate those.
Years later someone in the city seemed to realize it, and changed the design of the roundabout. It's better now, but there are still a few areas they overlooked that have the potential to cause accidents.
You seem to have misread my post. Everyone drove wrong. I seemed to be the only one to notice it, and started avoiding that roundabout, because driving with the correct right of way rules during busy times would lead you to t-boning another car. Other people I talked to said "no, that's just how you're supposed to drive on that roundabout" (it wasn't, and the signage was eventually updated many years later).
If _everyone_ is driving through it incorrectly doesn't make it a bad roundabout, than I suppose no roundabout can be bad. If it's always the fault of the drivers and never the design, you can't really say 4 way stops are any worse in this regard either.
I’m trying to say that everyone driving through it incorrectly is not a great metric to judge bad roundabout. If everyone does it wrong and it’s still safer than a regular intersection, then is a success.
Of course I don’t know the numbers involved, so I can’t say if that’s the case here.
Or to visualize it another way - if you can image those intersections where there are two right turn only lanes, and one lane to the left of them that's right turn or go straight. Now imagine if all three lanes were right turn or go straight, and everyone made right turns - but if someone in the far right lane is going straight, they're plowing into the cars turning in the other two lanes.
After years they eventually fixed it and made the two outer circle lanes right turn only, which is what they should have done at the beginning. But even there they screwed up, because there's a street that enters the circle right after the right turn only signs, so if someone is entering from that direction and isn't familiar with the circle it's possible for them to ram into the other cars.
There are variations on this, sometimes, B can only go straight so that C can also go straight. C can also be used for a fully controlled U-turn. In fact, C is has the markings such that one can just go around and around and around forever in if one chose to do so.
All of the roundabouts here have overhead signage leading up to them that indicates which lanes are for each direction of travel. There are also lines on the roads themselves have solid and dashed lines. Never cross solid lines, optionally cross dashes. We get snow so lines aren't always visible.
I've been through many different roundabouts countless times and there is occasionally someone that doesn't get it right but the traffic is moving slowly enough that it unusually only leads to honking.
One strategy is to watch the faces of other drivers, people will be looking in the direction they will be turning.
After the neighbourhood complained, it's now a roundabout with 4 stops (not ideal, but not dangerous either).
The feature that seemed to be missing from the roundabout in the original post was any kind of signage. Normally in the UK, roundabouts have a sort of map view as you approach them, then on the islands are signs telling you where to exit.
I am from the UK and it makes me wonder why road design in the US is so bad. Just one minute of thinking about this as a lay person would reveal the problem with the design.
Is there some structural reason in the US that would cause it? Perhaps some lack of standards or approval process? Perhaps iteration speed is slower so they don’t get better? Some other incentives going on?
No, they don't, at least not in America. When you let American traffic engineers design a roundabout, you get this: https://www.google.com/maps/@38.8643875,-77.2755474,583m/
An actual roundabout DOES solve the tbone issue.
https://osm.org/go/eu8S4TeKc?way=50459468
(right-hand drive)
I think they're a bad design as they encourage drivers to go fast with the sweeping corners etc. Ideally, a roundabout should be designed to slow traffic joining it to reduce collisions and their severity. Trying to keep vehicles moving quickly at junctions is just asking for trouble.
Here's one of my favourite hybrid "roundabout" junctions:
https://www.openstreetmap.org/search?query=Boughton%20Heath%...
American traffic engineers would apparently disagree with you.
We don’t have four way stops though so instead it’ll be min/maj junction or traffic lights.
It’s extremely common in the Netherlands to replace crossroads and T-junctions with roundabouts to improve safety, but Dutch urban roundabouts are designed with safety as the main priority. This is achieved through single lanes, sharp entries, limiting forward visibility, and pedestrian and cyclist priority (via what are effective zebras).
For more information see eg: https://bicycledutch.wordpress.com/2015/10/13/explaining-the...
(Edit: fixed wrong link)
NL seems to quite commonly have this kind of physically large but medium traffic suburban junction, but outside of Milton Keynes and the outskirts of some towns that got heavily developed in the 60s, it's hard to see many places where we could just drop it in.
> That the Dutch roundabout, including the cycle tracks all around it, can be built in almost the same space of a traditional junction is the reason why so many are being converted.
From: https://bicycledutch.wordpress.com/2014/02/23/junction-desig...
I'm with you on how some will still be dangerous, and can require traffic stops. But it's still better than going back to a plain stops IMHO, and it's usually in portions where it was already dangerous before putting in the roundabout. In practice I've never seen a reversal of a roundabout to get back to a plain intersection.
The number of bad roundabouts is pretty common here, though. But it wouldn't entirely surprise me (based on other things I've seen) if there was a level of local incompetence that went beyond the norm. You're right that they can be improved, but (I mentioned this in another reply), sometimes that takes years or decades for whatever reason (and even then, they don't fix all of the issues).
Roundabouts are great sometimes, but they aren’t a magic bullet.
That said we have a nasty intersection in the area on a highway that they’re going to redo, which absolutely no one could have foreseen 10 years ago when they first put it in.
The 3 options were j-turn or roundabout soon, or a full on overpass type system in another 10 years.
J-turns are awful, so while that was their first idea it was thankfully put down. It would have been even worse as it leads into a school and most buses in the area would have needed to do U-turns on the highway, as well as new teen drivers. In Minnesota.
Old people complained about roundabouts because even though they’re used quite a bit in the area apparently they don’t drive and don’t understand them.
So, 10+ million dollar overpass for a town of 2,000 it is, in 10 years. Let’s hope not too many more people die before then, eh?
Yes, that is by design. Slowing traffic down, also in relatively low-traffic areas, is one of the use-cases for roundabouts in France. Mostly around villages and/or industrial areas.
If you think roundabouts slow you down (they don't really), just wait until non-rush hour at one of these "roundabouts" when you're the only car waiting on several sets of red lights, or during rush hour when the lights have failed and it's totally gridlocked where traffic simply cannot pass.
All four way stops are badly designed. Roundabouts are not always the best options, but they're always better than four ways stops.
No matter how terribly designed, it's hard to entirely miss a roundabout. You basically need to be incoherent.
That said, I agree with your points, and I personally prefer roundabouts to queuing stops. They flow so much better, and really help to improve congestion/bottlenecking.
I think COVID really kicked the enshittification of drivers here into a new realm. That spat where driving tests were suspended in so many places and driving school wasn't workable has let a couple years worth of drivers onto the road who had almost no practical instruction, and it fucking shows. And it's not like most people were good before that. For the vast majority, driving is a chore and you can tell that by the absolutely bare-minimum efforts put into it.
When being taught how to ride a motorcycle, one of the lessons is a series of extra checks that you're not taught when learning to drive a car. These are known as lifesaver checks.
Entering a roundabout is a left turn in Ireland (right turn in right hand drive countries) so you would check over your left shoulder to make sure nothing was on your left. This is performed after doing a normal right and ahead check for traffic already on the roundabout.
I have never caught anything with a roundabout lifesaver (I have in other situations) but I can see how it's useful on roundabouts with multiple entry lanes, or if something like a bicycle had appeared on your right.
I suspect there isn't enough room for a roundabout, and we also don't tend to construct roundabouts on hills (I'm not sure why they're any worse than other junctions there). There's a steep gradient going uphill from South to North.
Normally it would be a two way stop, and I sometimes wonder why that wasn't chosen here. Likely because visibility is bad (trees, walls, curves - it's worse than it looks in the satellite image) and cars coming from the east and west can't completely tell that it's safe to enter the junction.
The other side may have a stop sign, but are they stopping?
Its sort of useless to know if you have the right of way or not when you drive defensively. Just assume you don't and only go if you actually see someone yielding/preparing to yield to you.
It's frustrating riding with certain other American drivers in other countries. I've met numerous folks now that seem upset that they have to actually pay attention to their driving and the traffic. Meanwhile I'm horrified that they're apparently just ... completely on auto-pilot in the US.
WSDOT has been encouraging them for a few years now, and my town has several new roundabouts as a result -- and lots of other cities across the state are using them. They've made navigating those intersections way easier, reduced traffic "waiting times", and generally improved safety versus a lighted intersection. I'm glad they're continuing to find ways to make them work.
It seemed when I was growing up in NJ, the state DOT was taking out the giant roundabouts that they were famous for, and now in Washington, they're having a huge resurgence.
It also does not help that NJ is the only state in the US that does not have a consistent rule about roundabout traffic priority.
I still get confused at the big roundabout in Kent, after coming off Highway 167 at Willis Street, but most others I've encountered are fine, despite the drivers who still want to stop before proceeding onto them even when there's no other traffic.
Roundabouts are a waste of space, disrupt traffic, and take more brain processing than I care to afford if I can help it. This particular example isn't even round.
In terms of brain processing, you get used to it and it becomes second nature. It is a skill.
Ones with multiple layers stress me out, there are more ways to screw up and more demands on your defensive-driving attention.
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=O============O=Ours is much simpler, with a round-a-bout on either side of a regional highway. One of the difficult parts about it is everybody is already jacked the fuck up (on account of 2 of the 5 input/outputs being extremely steep grade to enter/exit a river-crossing, with speeds averaging 65-70mph ["55mph" posted, oklol).
That wouldn't raise an eyebrow here in the UK, it's very normal for highway junctions to have on/off ramps that end in 2-3 lane roundabouts, one each side of the highway.
Yeah, if my driver’s ed class (both content and classmates) are any indication, a four way stop is anything but intuitive or brainless.
There’s a lot of time spent covering the right of way order, and a lot of people failing their driving test on it.
Roundabouts are only disruptive because of a lack of familiarity… the only way to build that familiarity is with practice. Sucks that you have to learn a new concept after a decade or two or four ~~in the industry~~ on the road, but seems necessary for progress.
I once saw a roundabout with stop signs. I assume it was an attempt to address this situation.
The problem occurs mostly when the dominant flow is given multiple lanes.
A fairly common solution/workaround is blocking the view of the approaching traffic, forcing it to slow down. But again, this doesn't work well on large roundabouts that allow people to speed up to of 30+ mph.
Here the situation is uneven road size, through traffic on the highway and odd angles. Perfect roundabout application.
Also, keeping your navigation display "north up" is much better than having one that will probably be laggy in a roundabout, confusing you on which exit to take.
If all else fails, look at the signage; I remember driving and a passenger not sure if the roundabout exit I was taking was correct, I said "Well there's a big sign there that says this way to our destination."
I've also seen a trio of 3 of them be adjusted (by changing lane markings and signage -- nothing of grand expense) in a way that was much more sensible and easier to follow than the original design.
It seems to me that a lot of the issues with them could be eliminated by having a bail-out path that is both safe and acceptable.
Logically, it seems like this ideally means providing the opportunity to simply go 'round again and do it over.
Or where that's not possible and there must be a lane with an irrevocable default exit, then: That exit should be low-cost and provide an opportunity nearby to safely stop and spend as much time as it takes to re-evaluate a second attempt.
It should never dump a driver into an unexpected 9-mile-long Pavlovian clusterfuck.
The lanes are painted to "spiral" so that if you take the furthest left hand, by the time you get to the 3rd exit, it's the outermost lane.
Led to quite a bit of ribbing from the passengers so perhaps this is a PEBKAC after all.
The (presumably) final markings[0] make things less confusing.
[0]: https://www.google.com/maps/place/High+Rock+Rd,+Washington+9...
1: https://titanww.com/what-is-a-pup-trailer/
3: https://www.youtube.com/watch?v=mU5L_2TMjKc (sorry, terrible handheld video)
I was looking at the markings that are there, and they made it seem like traffic approaching the roundabout would have priority over traffic already on it.
The map/diagram helps people not familar, the only really complicated thing is making sure you get in the right lane, and keeping an eye on those around you.
Then I started paying attention to the displayed layout. This helped me with the bearings and lane positioning. At least, that's one item off my list when I'm in the roundabout.
Then there is the less obvious stuff that happens multiple times per hour, like entering in the wrong lane given the desired exit (even though it is marked), vehicles inside the roundabout yielding to vehicles entering the roundabout (even though there is signage), or vehicles entering the roundabout failing to yield to vehicles inside of it (same signage).
As for non-standard roundabouts, those can confuse just about anyone since people often don't realize that it is a roundabout.
Ideally the sign would be 1) Rotated so that the driver proceeds from the base towards the top or sides. 2) Clearly depict the LOGICAL layout (bent slightly towards the physical) of what flow patterns _do_ during the roundabout from that input. 3) Also clearly depict which exits go where.
There should really be two signs actually, one before the diagram that lists (locally relevant roads / landmarks) by lane for sorting (if there's more than one lane in).
PS: The route map should also add a YIELD sign in mini next to the entrance with an according broken line. The interior lanes of roundabouts always have priority and all inputs are yield merges in.
https://wiki.openstreetmap.org/wiki/Tag:roundabout%3Dturbo
https://en.wikipedia.org/wiki/Roundabout#Turbo_roundabouts
https://www.arcadis.com/en-us/knowledge-hub/blog/united-stat...
https://en.wikipedia.org/wiki/Magic_Roundabout_(Hemel_Hempst...
Only fourth? Pssh!
The "turbo roundabout" might make this explicit, but it's not different.
I didn't say or imply this. The rule works for non-symmetrical roundabouts without issue. To phrase it differently:
If your exit is to the right of a hypothetical line extending across the roundabout in your direction of travel upon entry into the roundabout, go in the right lane. Otherwise, left lane.
> In scenarios like this you will inevitably have to switch lanes in some scenarios.
No roundabout I've ever driven through in the UK has required lane switching, unless I was in the wrong lane to begin with.
E.g. a standard 2-lane by 2-lane roundabout intersection may just as well look like this https://i.imgur.com/jqhMxW4.jpeg. Note the entrance markings allowing all lanes to go straight with 1 alternative turn direction per lane choice, the exit markings allowing dual lane exits in all directions, and internal markings allowing u-turns (the roads in this case have medians farther out). It has some of the downsides you mention but also some upsides in exchange for allowing slightly more lane flexibility. Regardless, you're definitely not supposed to follow the turbo's rules in that roundabout.
Now you could "no true Scotsman" it and say all the other roundabout types aren't roundabouts because they are supposed to be like turbo roundabouts to be so... but that still leaves needing the distinction in types, for which everyone calls one a turbo roundabout and other variations different types of roundabout.
> Drivers going northbound on SR 203 traffic may need to yield twice – once when entering the roundabout and again if traffic is passing between the two islands. If you think about it, that’s just following the same rules a second time.
The one key difference from the average (American) roundabout is the second yield. After you've waited your turn and entered the roundabout, you're required to yield again within a few feet. Obviously this is not an impossible task, but the signage leading up to the roundabout from northbound SR 203 doesn't at all indicate the shape of the roundabout. The navigation sign at the entrance only shows a single roundabout.
The second yield point is indicated with the standard yield sign and triangle markings on the road. But judging by the amount of detritus scattered on the ground, as well as the recent addition of "YIELD" text painted on the road and orange flags attached to the yield sign (both not present at any other entrance to the roundabout), the yield-twice pattern is not obvious to everyone.
Plus, the topology of the roundabout isn't conducive to seeing this from the ground, either; the relatively sharp right turn leading into the roundabout places the second yield sign out of your forward vision when you're approaching the roundabout, and the whole intersection itself is very slightly tilted away from the northbound entrance, making it really tricky to see and understand it when approaching.
---
Anecdotally, almost every time I've driven through here while there is simultaneous traffic from northbound SR 203 and northbound 203rd St. SE, the northbound 203rd St. SE traffic ends up being cut off by drivers failing to yield at the second entrance.
> Making a roundabout for everyone
ctrl-f "walk", "cycl", pedes". Nothing.
Caveat: this is for simple, single-lane roundabouts. Multi-lane roundabouts are gnarly for cars and worse for cyclists.
My preferred roundabout is separate bikepath that joins the road just before and is a part of the same surface, usually found in bike friendly places.
[1] 60000+ km throughout Europe
Here is an example of the kind of thing I had in mind: https://maps.app.goo.gl/mexZWJ9ZP1yvEJ7k7
As you can see, they are building a pedestrian overbridge on the north side, but consider what you would have to do to traverse in any other place as a pedestrian (or get across anywhere currently). Here's a suggestion from Google (i.e. just pretend you're a car): https://maps.app.goo.gl/AiBoyWk4Z7bFr21z5
The above is in one of the busiest parts of this city. It's not like there are no people wanting to walk. In fact I found myself in exactly this position here not too long ago. I wanted to get from the mall side to a cafe on the opposite side. I gave up and ate a sad meal in the mall :(
Edit: Here's another example (with Google's hilariously impractical suggestion): https://maps.app.goo.gl/pati5dBBTnSgxZ1m9
Although ideally the crossing on a roundabout should be set back so far they arguably aren't even on the roundabout... so space is an issue.
I know all those speed bumps are annoying when you are driving but elevated crossings and bike paths are great traffic calming solution as screaming your engine between speed bumps soon gets very old and tiring and even the most aggressive drivers just end up staying between 12 and 20mph (20-35kph) in the sections that involve pedestrians and cyclists.
As a cycling Dutch I prefer a roundabout to a traffic light. As a roundabout doesn't force a fullstop and takeoff again. Also because stopping/get going again is more difficult for elderly/injured people.
[0] https://www.google.com/maps/@51.9970826,4.3550136,195m/data=...
[0] https://bicycledutch.wordpress.com/2015/10/13/explaining-the...
[0] https://cities-today.com/uks-first-cyclops-junction-opens-in...
Cars turning right at an intersection are an order of magnitude more dangerous.
The roundabout forces drivers to slow down in any case, so they are already reducing speed.
Social norms is another thing, but if every driver is in asshat mode you are going to have traffic problems regardless of infrastructure.
Want to see it work? Visit Carmel, Indiana.
I suppose it depends on what is meant by traffic and I suppose it does depend on whether "slows traffic" means slowing down compared to just zooming past with a green, or drives at a slow speed. I would think that a) it slows traffic compared with zooming past and b) it's not that slower
On average, I suppose, smoothly moving traffic at slightly slower speeds will be more efficient than 3 lanes of stopped traffic and 1 of fast.
"Drivers going northbound on SR 203 traffic may need to yield twice – once when entering the roundabout and again if traffic is passing between the two islands. If you think about it, that’s just following the same rules a second time." [my emphasis.]
Firstly, of course, if you are new to it and have not heard about it in advance, you won't have much time to think about it. Secondly, if your mental model of a roundabout is "yield to enter, then you have right of way", this will seem counter-intuitive. I hope they put up a yield sign and corresponding road markings at that point, but the latter are not there in the accompanying aerial photo.
I am also curious as to how navigation systems will tell drivers how to negotiate this roundabout. They have trouble with a somewhat similar roundabout in Kingston NY, at the intersection of Albany ave., Broadway and Colonel Chandler drive.
Update: The accompanying video shows there will be yield lines at the point I am concerned about, but it is also ambiguous about how the rules of the road apply there: "The circulating roadway goes around and between both central islands... Those drivers already in the circulating roadway have the right-of-way."
>The new roundabout needed to be built in the same space as the old intersection. To the east is a steep hill. To the southwest there are protected wetlands. There wasn’t space or budget to mitigate the potential impact in either direction.
Budget to fix the hill yes, it's a real life thing, but one can still wish they had been able to allocate things to do it right. As far as the wetlands... https://i.imgur.com/x0WGHXa.jpeg how many lives is a small part of that narrow strip of wetlands between a farm and 2 roads worth? Easy to change? No... but the right thing to have changed? I think so. Now that they've done neither the intersection is still not very safe (IMO, time will tell) and the limited budget was consumed in doing so.
Solely focused on dealing with "what sounded like the easiest and cheapest intersection to put in" I think they did a decent job, I just wish they had been able to do more. Intersections like this not only remain unsafe but give a bad public taste to roundabouts that are able to be properly done - "Oh I HATE roundabouts, I can't ever tell when to yield or where the lanes go. I don't want one in town" when really it's just a horrific roundabout they went through.
Waiting a few months to see what happens with real traffic...
When asked why, the answer is reducing “points of conflict”, which is a static variable. There aren’t actually studies being done before or after to see if makes the flow of traffic better.
They are also adding them in walkable areas with the express intent of “traffic never stopping” which doesn’t go well with pedestrians crossing the street.
I think we can find better ways to spend money… including the salaries of the people dreaming up bizarre applications for these things.
Traffic gets much heavier and we'll need stop signs at our roundabout near my house. During rush hour it has predominantly one flow of traffic and nobody slows down below 30-35 mph so getting into the roundabout can be difficult. A stop sign would defeat some of the point of a roundabout but it may become necessary to enforce safety.
Roundabouts are great, but they should probably be round. In this case, it seems that it'd be easy to navigate if the two roads were brought into a single, simple roundabout intersection like you see at any other location.
Whether or not it works or is a good idea is not something on which I'm opining.
Imagine the main road going North-South, and you're entering via East to go South.
Because of never-ending traffic going North-South you just don't get to enter.
https://maps.app.goo.gl/v76ajKvXhzfAdGZ29
Or you can also have dedicated lane that only go to the nearest exit:
Even UK drivers struggle a bit with this one!
An other baffling design I've encountered in the UK is a roundabout with traffic lights half-way through.. Wasn't the concept based on removing traffic lights to fluidify traffic..?
As a whole, if designers come up with far-fetched designs where drivers struggle to understand what's going on, they are doing something very wrong. Assuming the average driver is already barely in control (phone distraction, screaming kids, lack of sleep, medication, subpar vehicle control, etc), the last thing you want to do is remove even more situational awareness by coming up with over-complicated designs that require serious thinking.
The argument that people will slow down because they don't understand what is happening is a fallacious one. Yes, they will slow down, but then, under stress, they will probably default to some instinctive basic reaction which has a high probability of being incorrect, leading to accidents. An illustrative example can be made with traffic videos of American roundabouts.
https://www.youtube.com/watch?v=Xu0VJ7Vo5pg
So in conclusion: Keep It Simple Stupid. (KISS)
I believe traffic lights are always trying to solve a capacity issue - where the roundabout has hit it's maximum capacity and is suffering some throughput issue, which tend to sort of get exponentially worse. With traffic light sequencing, particularily dynamically, there is always a way to even out the flow - prioritize a flow that is backing up undesirable or give a particular entrance fair chance to enter the roundabout.
Though once there are traffic lights on every entrance, plus traffic lights mid roundabout and some/all exits, and explict lane markings and merges I think it's not a roundabout.
Slowing down is important though, as it give drivers time to think and react. Whether they choose to use that time correctly is a problem, but hopefully some or all of the other drivers can use patience and avoid an accident. Where accidents happen, I see it's often from mistakes from two drivers, and it's relatively low speed. Better still, accidents are at shallower angles, so injuries are rare. I've heard an statistic that could well be fake that roundabouts have more accidents, but significantly better outcomes overall.
The other issue in the UK is massive signalised roundabouts used for junctions where traffic volumes clearly justify a proper grade separated junction like a stack, purely to penny pinch. South Mimms A1M/M25 junction is a good example, or the M2/M25 junction where they eventually had to put in free flowing slips eastbound to northbound because the roundabout was constantly congested.
That's not really a problem with roundabouts per se though, it's just bad design choosing an inappropriate junction design purely to avoid having to pay for bridges
Fixing one junction might just move the congestion to the next one, and if you continue fixing them you turn all the cities into jungles of concrete.
I fully agree, and I also think that the "original" roundabout design serves that purpose well, although throughput might different than with dynamic traffic lights.
The point I was trying to make was that slowing down traffic through added complexity could be a dangerous approach to take. It's a switch from a low cognitive load approach by simple design -slow down to a stop/almost stop, look to one side, give way if necessary-, to a slow down of higher cognitive load -slow down, figure out how to navigate a more complex (new) intersection, and maybe remember to give way-. So where in the first approach cognitive load is used to assess how to give way, in the second approach some of that load is used to deal with a more complex/unfamiliar situation. And for some users, I argue, that could already push them more towards accident territory as less cognitive capacity is available to properly assess the traffic situation. Sometimes less is more.
This is indeed a weird one from a US perspective.
The way to think about it is not as a roundabout with traffic lights, but as a light-controlled intersection in the shape of a roundabout.
A roundabout-shaped intersection can handle more variations than a normal intersection, you can have more than 4 roads, or roads entering at odd angles.
As for what the advantage is of having lights on the roundabout as opposed to on the approach, I have no idea.
One example of where this has been an ongoing issue for decades is the Black Cat Roundabout on the A1 (https://en.wikipedia.org/wiki/Black_Cat_Roundabout). It's gone through numerous changes to improve things, with lights at various points being one of them. Finally now though its being completely redeveloped to a grade-separated junction as traffic has massively outgrown the roundabout.
Most people here actually prefer roundabouts to traffic lights because you keep moving (although this is partly selection bias- traffic lights are deployed at junctions where a roundabout would fail to evenly arbitrate the different flows )
There are two skills you need to pick up to deal with any roundabout system. The first is judgement of how distant other vehicles need to be before you can enter. As a learner I used to irritate the drivers behind me by being far too cautious; on a busy roundabout you can't expect an enormous gap, so you need to know what length of gap the other drivers will expect you to take advantage of. This you can only learn from experience.
The other is to plan your route, because you need to choose your entry lane based on where you want to go. These days your navigation app will probably tell you the best entry lane.
https://en.wikipedia.org/wiki/Magic_Roundabout_(Swindon)
(To be clear I like roundabouts)
(15mph residential access road - top right) (25 mph farmland road - bottom) (50mph country highway - left and right)
Previously, only drivers from the 15mph and 25mph roads had to stop!
Visibility coming from the south would also be terrible to check for incoming highway drivers (left is blocked by foliage, right the road curves out of sight), so getting the highway drivers to slow down is a welcome improvement here.
There is also not enough space to add at the intersection here either, its seemingly bordered entirely by private land.
A roundabout was the correct choice.
This is something which drives me crazy with a decent number of roundabouts that the Wisconsin DOT constructs. You have a rural intersection where a local road crosses a major highway, and the local road has a stop sign in either direction. Then the DOT slaps a roundabout in there, greatly inhibiting the highway traffic which is 95% of the traffic going through that intersection. That is not a good use case for a roundabout! But for some reason they insist on doing them anyway. It's terrible road design.
(Not sure if this is the reasoning Wisconsin would use though.)
I think the same is true of roundabouts. One part of the experience that seems almost never to be mentioned is the experience for a passenger when encountering a series of roundabouts. Let’s say you had some bad oysters and are resting your head in the back of the car on a pillow and praying you can make it home before you upchuck your dinner. Perhaps some road engineer decided to put 5 or so roundabouts consecutively to “optimize traffic flow” then somewhere around spin number 3 you lose your stomach on the backseat. Perhaps the trip was not “optimal” for you.
Driving in Morocco is a very special experience. Some roundabouts follow the 'priority on the right', which is a default if the junction doesn't indicate priority, in much of Europe (especially France). This means you give way to those approaching the roundabout, as they are on your right. But there are also roundabouts where you have priority on the roundabout. The only way to tell are to look at the road markings which help to indicate the priority.
> the sheer lack of education around how to navigate one makes for a very unpleasant experience in most cases.
If we're talking about the United States, then the problem is the lack of driver education in general.
And so the lack of experience continues on forever.
Come on, man, people will figure it out.
There will always be the dashcam vid of the yokel who tries to make a left into one despite the obvious signage and directional nudges, but dashcam youtube has shown us there's always people out there who have no common sense and should not have a license. Just pop some popcorn and continue scrolling.
Mini-roundabouts are commonplace in the UK, e.g.:
https://www.google.com/maps/@51.4072632,-0.2739497,3a,29.6y,...
It's not quite the middle of nowhere, but definitely quite rural. I wouldn't expect to find pedestrians out there.
like in a normal roundabout you always yield to the people in the roundabout basically assuring things won't get "stuck" if one road has much more traffic then another
but on the picture it looks (through the lines) as if the people in roundabout have to yield
in which case it wouldn't technically be a roundabout but just a 3 way intersection which separated and lanes to archive some traffic flow optimizations and calming as necessary (as such the sharp edges might angels might be very much intentional)
and I agree it looks confusing but it also looks like it will slow down traffic in all but one of the directions
EDIT: Photos on google maps have much more sane lane markings and it resolves the question if you have to yield when entering it (yes you have). It generally looks much less confusing there.
Features two lanes and five exits, as well as a pass-through bridge for a highway. When you drive on the highway, you don't even see it.
https://i.prcdn.co/img?regionKey=W3NBJc2RmiFQ3sgVAHxBDg%3D%3...
https://www.openstreetmap.org/search?#map=17/50.841903/6.016...
https://www.openstreetmap.org/search?#map=17/51.404972/5.502...
https://www.openstreetmap.org/search?#map=17/51.982028/5.978...
And I raise you the double highway fly over: https://www.openstreetmap.org/#map=17/52.056112/5.122311
My my local pet peeve of horrible roundabouts, you got cycling paths, a tram line, a bus line with different exit and cars. (the hexagonal cycling path with internal car circle causes the cars to not see a lot of the cycling paths making accidents frequent): https://www.openstreetmap.org/#map=19/51.996997/4.354979
All the roundabouts around me I wish they would just get rid of, I can navigate them just fine, but they are way too small, over congested, and dangerous because the 5 seconds you have to read the signs as you approach to know whats going on is too much for anyone non-local which makes them unpredictable and nervous drivers.
I'll take it any time over a typical highway exit; if you miss it, or uf you take a wrong one, it's usually dozens of miles before you have a chance to take any corrective action at all.
This roundabout is perfectly fine in practice.
I'm not a fan of roundabouts, but the recent WSDOT roundabouts I'm subjected to have gentle curbs, at least for now, so that part isn't so bad. The part where I actually need to look left and right simultaneously to see if there's room for me to join the flow, and also watch for pedestrians (if present) isn't so great.
And I'm really not a fan of the unbounded wait when there is a large flow that crosses my entrance, which could result in a very long wait when the large flow comes from rush hour conditions or a ferry offloading.
Of course this could just be banter, in which case: absolutely not, we tout our motors through circular-wirculators just like anybody else!
https://en.m.wikipedia.org/wiki/Traffic_circles_in_New_Jerse...
"Larger vehicles may drive over the center islands for tight turns."
But for multi-lane ones I absolutely lose my shit and freak out when I get into one. Many decades of driving experience, but when in Europe (France, Italy, Spain) i encounter a multi-lane roundabout, every time it feels extremely confusing and unpredictable. People moving in all directions, cars, scooters, you need to calculate which lane you need to get into, and get out of, and do all that while accommodating crisscrossing neighboring vehicles who are all also trying to maneuver in every direction. Having to turn the entire time makes it feel very fast and dangerous, always paranoid about crushing some scooter that I didn't spot from one of the many angles while turning. Doesn't seem to get easier with time for me either, unlike all other driving. Glad we don't have multi-lane roundabouts in CA.
There are major cities in those countries with a few exceptionally gnarly ones, though. I don't blame if you're traumatized if you ever found yourself circling Arc de Triomphe in Paris, for example.
When done properly, multi lane roundabouts can be quite efficient. They are common in Europe as an alternative to just having a lot of traffic lights at any junction. Some of the bigger ones can also have traffic lights.
A good guideline is that if you need to go 3 quarters around, you probably want to be in the left most lane when you enter and move right as you progress. In case of doubt, just go around a second time. If you are too far right, merging left is something you want to be careful with and not necessarily legal in some places. But it's not that different from sorting into the wrong lane for a crossing. You kind of commit to where you exit before you enter. Usually the signage should help.
The most annoying thing about roundabouts is the navigation endlessly going "At the roundabout take the second exit" (i.e. go straight on), which gets really annoying if you are on the ring road of some city that has roundabouts every few hundred meters. Which accurately describes a lot of smaller cities across Europe these days. Safe and efficient. But also tedious. If in the Netherlands, beware of your right hand dead angle and be on the lookout for scooters, e-bikes, etc. when you exit a roundabout. You are supposed to yield to them and they can really come out of nowhere.
The centers of roundabouts are typically overgrown wastes of scraggly grass mixed with litter. Each a tiny sacrifice zone. They remain that way because nobody goes there on foot. We just see the mess from our cars.
A roundabout takes what could have been a village green and turns it into something just barely less terrible than a highway cloverleaf.
...
So I actually read the article and am not really proven wrong. They do this insipid
> Making a roundabout for everyone
thing, like laying pavement is the Civil Rights Movement, but "everyone" seems to only mean "vehicles", a word I see several times, together with "drive", but never "walk". I see no crosswalks, no pedestrian flashers, and no bike lanes. And the center island has been designed so larger vehicles can drive over it; I understand their reasons, but that also means it provides less protection to anyone seeking refuge there as they try to get across.
Sometimes traffic isn't a problem to be solved. It's the universe telling you that there are already too many cars.