Crash prone 'modern roundabouts'

[kalvado]

Not disagreeing that intersections should be designed to facilitate the movement of driver's of all backgrounds. But drivers of all backgrounds are more readily familiar with the most common types of intersections, of which the roundabout is not one. Signals are a part of nearly all communities across the US, so pretty much all licensed American drivers know how they work because they see one every day. That is not true for roundabouts. Carmel has tons of roundabouts, but Indianapolis has almost none. Any non-Carmel-based driver in Carmel is going to drive through a roundabout, and for our sake, let's hope they can figure out how they work. They'd understand them better if they were used to seeing them. It doesn't take a genius to work that out.

And as I said in my post, roundabouts may not be a realistic solution for all intersections. And if the plan is to slow down how many roundabouts are being installed, we should probably abandon the concept altogether. There are still too many Americans who never see them, and who might be confused or just unphased by the intersection style (and enter in such a way as to unintentionally cause as much carnage as possible -- drifting across lanes, failing to yield, etc). Signals generally work well because they are familiar. Not straightforward. Plenty of signals have bizarre layouts or curves. DDIs, for instance, or Michigan Lefts, but most work OK because drivers are familiar with RYG indications.

You know, there is one fundamental difference between roundabouts and traffic lights: traffic lights mostly provide positive right of way for most traffic. Left turns or rights on red is when you don't have positive right of way - and both are moves that are associated with elevated risk. Mostly because those require quick analysis of oncoming traffic and a quick action. I saw drivers who refuse to turn on red, and many of them have gray hair.  Moreover,  multilane roundabouts, ones which our friend Trade really hates, require looking at multiple lanes of traffic, which can flow out of tune. Possibility of a costly mistake becomes even higher... 

There are other situations where drivers have to yield without an option - stop signs, highway entrances - but stops are usually associated with low speed and/or low traffic volume, and same people who avoid turns on red also responsible for "avoid freeways" option in Waze. Roundabouts are often hard to avoid.

So, where I was heading? Ah, ok, the message is: roundabout brings yield issues and associated stress and possibility of mistake where design can eliminate those issues, especially on busy roads. And, if you ask me, it is often too much stress for too little gain overall.
Roundabouts, by design, are a gamble - would that car exit? Would this car stop (as it should, or driver assumed I am exiting)? Do I have enough room? Is there a pedestrian behind that nicely obscuring vegetation on the island (obscuring the view by design)? THis is all OK with 5 cars a minute intersection, but roundabouts a build to handle 10x that traffic.
I would say I am in my best years right now, and I can handle the issue - but I still don't like it. Would I be able to handle this when I am in same age group as uncle Tom currently is? We will see. I would be swearing even more than today, that's for sure.

[kalvado]

Now, are these DOT's going off false information? It certainly seems that way! But to tie into my previous post (most of which you seem to have ignored), the safety records of roundabouts could very well be tied to driver unfamiliarity. Of the 165 crashes at the Sterling Heights roundabout (above), how do we know they weren't all drivers who had never seen a roundabout? Your argument is that signals work well because drivers understand them. My argument is (potentially) the same for roundabouts: they would work well if more drivers were familiar with them. Not just the ones who use it every day: all drivers. That's only conceivable if roundabouts become as common as signals. If that's not conceivable, we need to stop installing them immediately.

Frankly speaking, who would work as an engineer who's biggest achievement in a career is rebuilding an intersection according to 50 year old buleprints? That seems to be the case for many NYSDOT folks. I suspect there are few, if any, people able to design things based on knowledge and experience, not on "just because".

As for drivers.. assuming a newcomer has 100x higher chance  of crashing (which is generous), and a ballpark design target of 1 crash per 1 million vehicles, those 1000 crashes in Trade's table should be enough to ensure that 10 million drivers are now familiar with roundabouts. Since it one year data only, this thread goes on for a few years, and there are few more states having high event count on roundabouts - there should be no problems effective tomorrow as everyone in US now had a chance to meet the miracle and narrowly avoid an accident - or participate in one....  Would you bet $20 on that?

[skluth]

But drivers of all backgrounds are more readily familiar with the most common types of intersections, of which the roundabout is not one.

I deleted the rest of the quote because this line stuck out like a DDI in rural Kansas.

Why do you think roundabouts are an uncommon intersection? I've seen them since I was a kid and I'm 62. I didn't see them often when I was first driving, but I had seen a few, mostly in parks and bigger cities. I thought they were fun when my dad drove through them and loved how easy they were from the first time I used one. I enjoyed their utility when I was stationed in Spain. I think most of the people who hate them are the same get-off-my-lawn types who don't turn right on red even if you can see no vehicles for blocks.

Are there badly designed or misplaced roundabouts? Sure. I've been on a few. But they're common enough that people need to accept that knowing how to drive in one should be a requirement for driving. They're far more common now and when properly done greatly improve both safety and traffic throughput. I think the main problem is some whiny drivers don't want to think at all when driving or are too busy doing something else, and roundabouts aren't very forgiving of those types.

The only reason you might think they're uncommon is they aren't around you. By that logic, a citizen of Houghton MI could claim freeways were uncommon because the nearest is about 200 miles distant. But there's a roundabout in Marquette. Not close, but a lot closer than any freeway. You can go a lot of places and find roundabouts. Not any less uncommon than freeways.

[tradephoric]

According to data from the Indiana State Police included in the article below, the Carmel roundabouts at 116th @ Illinois and 116th @ Pennsylvania have crash rates of 13.5 MEV and 16.28 MEV respectively.  Considering the average crash rate of signalized intersections is about 0.8 MEV, these Carmel roundabouts are seeing 16x to 20x more crashes than that what a typical signalized intersection would.  In addition, these roundabouts are well inside the city limits of Carmel meaning that drivers would have had to circulate through other Carmel roundabouts before circulating through the crash prone roundabouts along 116th.  I don't believe the high number of crashes at these Carmel roundabouts can be excused away by driver unfamiliarity.  Maybe some drivers in Carmel still don't know what the hell they are doing even after driving through hundreds of roundabouts in the city, but i don't believe they are unfamiliar with them (ie. never drive through them).  Even Indianapolis residents who rarely visit Carmel should have some experience driving through roundabouts as there are currently about 10 modern roundabouts in Marion County (including a multi-lane roundabout right next to Indianapolis Motor Speedway). 

Top 4 intersections for accidents all in Hamilton County
https://www.wishtv.com/news/i-team-8/top-four-intersections-for-accidents-all-in-hamilton-county/1273973180

I do think driver education is needed.  When you think about it, it's actually pretty complicated to teach drivers how to properly drive through a roundabout, especially for east coast drivers who are use to driving around large traffic circles.  In a traffic circle the circle is the main roadway and a "straight arrow" would mean to continue around the circle... in a modern roundabout the circle acts as an intersection, and a straight arrow means to exit the circle.  To most drivers a circle is a circle.. and some modern roundabouts have large diameters that mimic large traffic circles.  In that case how is a driver to know when they are driving through a modern roundabout and when they are driving a traffic circle?  As long as drivers get confused with the meaning of something as simple as a "straight arrow" sign, crashes will inevitably continue.

[tradephoric]

Below is an updated roundabout database which includes roughly 6,000 roundabouts in America.  There will be 10,000 roundabouts in America within 10 years assuming they continue to be built at their current pace (ie. about 400-500 per year).

http://www.mediafire.com/file/ashf2dt18zac1ly/Modern_Roundabouts_%282018-Aug%29.kmz/file

[jakeroot]

So, where I was heading? Ah, ok, the message is: roundabout brings yield issues and associated stress and possibility of mistake where design can eliminate those issues, especially on busy roads. And, if you ask me, it is often too much stress for too little gain overall.

Yielding is still an inherent part of traffic lights. The flashing yellow arrow has become immensely popular over the last ten years, due to its ability to reduce wait times and reduce collisions associated with those long waits. I'm sure if you asked Trade, he would not be for protected-only left and right turns across our road network (if yielding is too much for drivers to handle).

I would not say that they're a useless feature, but sometimes, black-and-white road regulations can create disobedient drivers who feel like the government is trying too hard to control them, or that the government doesn't know what's best. California has by far the worst red-light-runners that I've ever seen, and it just so happens that virtually all left turns in California are protected only. Coincidence? I think not.

But drivers of all backgrounds are more readily familiar with the most common types of intersections, of which the roundabout is not one.

Why do you think roundabouts are an uncommon intersection?

I don't know how many traffic lights there are in the US. The only way I could figure it out was guessing based on the limited data I have available:

There are 3035 signalized intersections in Chicago proper, with its population of 2.705 million. That works out to one traffic light for every 891 residents. Dividing that by the population of the US (325.7 million), and you get 365,544 signals. That's very sketchy math, but it's the best I can do right now. According to Trade, there are about 6000 roundabouts in the US.

So,

365,544/6000 = 60.7 signals per roundabout. I think a fair conclusion, from that very basic math, is that roundabouts are nowhere near as common as signals. Obviously, the most common intersection is the stop sign, but at intersections that warrant a some form of four-way traffic control beyond stop signs, you're far more likely to encounter a signal than a roundabout.

Of course, in some states, some cities over-represent roundabouts. I don't know how many roundabouts are in Indiana, but I bet about 90% of them are in Carmel. If roundabouts were spread out a bit more, there might be better opportunity for drivers to practice them.

As it just so happens, you are correct: I have very few roundabouts near me. But I live in a metro area with a population of 3.7 million. How many of us never regularly encounter a roundabout? Probably most. When we do run into one, usually out in the country, we don't have much of any practice or experience to go off. So we just have to do our best. Sometimes, that is asking a lot of drivers.

[kalvado]

So, where I was heading? Ah, ok, the message is: roundabout brings yield issues and associated stress and possibility of mistake where design can eliminate those issues, especially on busy roads. And, if you ask me, it is often too much stress for too little gain overall.

Yielding is still an inherent part of traffic lights. The flashing yellow arrow has become immensely popular over the last ten years, due to its ability to reduce wait times and reduce collisions associated with those long waits. I'm sure if you asked Trade, he would not be for protected-only left and right turns across our road network (if yielding is too much for drivers to handle).

I would not say that they're a useless feature, but sometimes, black-and-white road regulations can create disobedient drivers who feel like the government is trying too hard to control them, or that the government doesn't know what's best. California has by far the worst red-light-runners that I've ever seen, and it just so happens that virtually all left turns in California are protected only. Coincidence? I think not.

Of course, there are yields around, and we do fine with them. 
Basically the question is when yield-controlled option  is feasible, and when mandatory yield-controlled move is feasible.
Trade's message effectively is that yield to 1 lane is OK,  yield to 2 lanes is acceptable, yield to 3 lanes is a no-go. Do you think there are any FYAs with 3 lanes of oncoming traffic?

My message is a bit more tricky. For an intersection with unequal arms (What I have in mind is a pair of circles on a local  EW arterial near interstate exit, circles are placed  where NS side collectors join arterial) yielding becomes unnecessary more involved. Let me try to elaborate....
With light (or side road stop) controlled  intersection, through traffic (WE and EW) clearly goes into separate no-yield group. And that EW is a majority group given the traffic distribution. Any yielding/yield to traffic is clearly identified by position on the road (and blinkers, although that is less certain); especially with dedicated turn lanes.
In case of roundabout, separation becomes much less certain - and through EW traffic  should be prepared to yield to oncoming through WE traffic. I am actually somewhat a victim of this, as I make a left turn (Westbound>south) on one of those circles - and invariably oncoming WE drivers expect me to continue straight like 95% of traffic does. At least twice a week someone has to step on brakes to let me use my right of way - and I slow down in case their brakes  are not as good as they think. I really think that is the highest accident probability on my commute.
Opposite problem - but another side of the same coin - is WE drivers stopping and yielding to straight-through EW traffic when there is no conflict. But there is a 5% chance that driver is making a turn... 

This wouldn't be an issue on a bigger circle, but intense desire to shoehorn them everywhere is also a part of a problem. 

[jakeroot]

Of course, there are yields around, and we do fine with them. 
Basically the question is when yield-controlled option  is feasible, and when mandatory yield-controlled move is feasible.
Trade's message effectively is that yield to 1 lane is OK,  yield to 2 lanes is acceptable, yield to 3 lanes is a no-go. Do you think there are any FYAs with 3 lanes of oncoming traffic?

Oh my god, yes. They're everywhere around here. More than a few across four lanes (such as here: northbound WA-99 @ WA-509). Kennewick, WA has a double left FYA against three lanes (here: Hildebrand Blvd @ Plaza Way). From the data I've read (I can provide links), they both work very well. Vancouver (BC) also has one identical to the Kennewick intersection (here: northbound Main St onto the Dunsmuir Viaduct). BC is full of permissive lefts across three lanes, many without any protected phasing.

Part of the reason these seem to work well is that they reduce overall delay, so drivers aren't as pushy or risky as they might otherwise be. Another part, at least compared to roundabouts, is that drivers have seen permissive left turns before, so they usually have a good idea of what to do. Not everyone, obviously, as crashes are a part of all intersections, but overall available data seems to suggest fairly high levels of understanding (particularly in the case of the FYA, which apparently is so well understood, the FHWA didn't see the need for a nationwide supplemental sign).

My message is a bit more tricky. For an intersection with unequal arms (What I have in mind is a pair of circles on a local  EW arterial near interstate exit, circles are placed  where NS side collectors join arterial) yielding becomes unnecessary more involved. Let me try to elaborate....
[clipped]

This is a serious issue with small roundabouts. Roundabout traffic models, from the few I've seen, show drivers entering and exiting the roundabouts along the arterial, having barely slowed down at all (seemingly knowing exactly what every other car is going to do), but when a car actually does turn left, suddenly that entry leg slows down to allow them to make their left turn, before proceeding again at-speed. The problem, of course, is that drivers don't actually do that; everybody looks left, I think, but perhaps are caught off-guard when a car actually starts to head towards them, since they (apparently) weren't expecting it. So drivers sometimes have to brake hard or awkwardly (certainly not smoothly). I could see collisions happening this way, especially outside lane vs circulating traffic, since the outside lane's visibility of the circle is worse than the inside lane, and drivers might be tempted to just follow drivers through (also an issue at permissive left turns, but I can think of several ways to fix this).

This wouldn't be an issue on a bigger circle, but intense desire to shoehorn them everywhere is also a part of a problem.

True. If circles were larger, it would be very clear who you are supposed to yield to. You could basically ignore all traffic on the other side, since they're 5+ seconds away from being a worry. But for some strange reason, agencies seem hell-bent on these tiny roundabouts with low speeds. We should really consider dropping the "low speed" requirement for "modern roundabouts".

[kalvado]

(clipped with huge scissors)

My impression is that the main difference between us here is that a glass is half-empty for me, but half full for you. You believe yield issues can be resolved - I believe they shouldn't be created to begin with; you believe that small roundabouts are a problem of agencies - I think the problem lies with the concept of rebuilding smaller intersections where there is not enough footprint available (and I mentioned few pages back how roundabouts are a dead end in reconstruction sequence)...

As for FYAs and multilanes.. WOuld be interesting to see how things would look like once there is more statistical data...

[DaBigE]

We should really consider dropping the "low speed" requirement for "modern roundabouts".

I can almost guarantee that will never happen. There is a direct relationship between speed and amount of injury. Lower speeds and traffic "calming" have been high on the list of benefits of modern roundabouts since the beginning. Raise the speeds and your pretty-damn close to the rotaries that many are trying get rid of.

Overall, there's still a huge educational gap with roundabouts, especially multilane versions. FYAs aren't much different in that regard, but are arguably more intuitive to the new user. Consider this: there are 19 states that do not require formal driver education, according to the Washington State Legislature. We have new drivers in 19 states largely basing their driving habits on their parents or guardians and what they see in GTA. Even in the states that do require formal driver education, roundabouts still aren't necessarily part of their DE's manuals.

[kalvado]

Overall, there's still a huge educational gap with roundabouts, especially multilane versions. FYAs aren't much different in that regard, but are arguably more intuitive to the new user. Consider this: there are 19 states that do not require formal driver education, according to the Washington State Legislature. We have new drivers in 19 states largely basing their driving habits on their parents or guardians and what they see in GTA. Even in the states that do require formal driver education, roundabouts still aren't necessarily part of their DE's manuals.

I don't buy that. I am from the state where pre-license course is mandatory. Roundabouts were discussed in my class, which was way before current construction fever. As I said, I have about 2-3k/year, or a total of 10,000+ passes through roundabouts as a driver by now; I have seen 1 (one) total screwup. No accident, though. Most cases of confusion are with people who err on the side of undue caution (yielding while in circulating lane, mostly) and would not lead to accidents. There is a noticeable amount of "f#ck you and your right of way" folks - but that is more or less consistent with what I see on busy stop signs in quantity and driving style. Overall you may assume that drivers know the rules, but sometimes caught with unexpected traffic. Local media also did its part in educating drivers,
Yet we do have some accident prone roundabouts, though... 

[tradephoric]

There are 3035 signalized intersections in Chicago proper, with its population of 2.705 million. That works out to one traffic light for every 891 residents. Dividing that by the population of the US (325.7 million), and you get 365,544 signals. That's very sketchy math, but it's the best I can do right now. According to Trade, there are about 6000 roundabouts in the US.

Your estimate sounds pretty close Jake.  In 2007 the FHWA estimated that there were about 311,000 traffic signals in America and at that time there were about 301 million people in America.  That turns out to be one traffic light for every 967 residents.  Assuming that same ratio, at 325 million people there would be about 336,000 traffic signals today.  The FHWA might estimate the total number of roundabouts at 4000-4500 as they probably wouldn't consider all the private subdivision roundabouts in that database i linked; and rather focus on city, county, and state roundabouts.  Out of 100 traffic signals, if one or two of them are converted to roundabouts that seems reasonable and nationally that's the ratio we are seeing.  But you look at a place like Carmel, where 90% of the traffic signals are being converted to roundabouts, they are coo coo for cocoa puffs. 

[tradephoric]

Saying that a roundabout forces drivers to slow down is as silly as saying that a red light forces drivers to stop.  Yes, someone can post videos of drivers blowing through red lights too, but a driver blowing through a roundabout without slowing can be extremely dangerous.  WARNING!  These are graphic videos of serious roundabout crashes.

https://www.youtube.com/watch?v=Piqjlwh3qR4

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

[jeffandnicole]

Saying that a roundabout forces drivers to slow down is as silly as saying that a red light forces drivers to stop.  Yes, someone can post videos of drivers blowing through red lights too, but a driver blowing through a roundabout without slowing can be extremely dangerous.  WARNING!  These are graphic videos of serious roundabout crashes.

https://www.youtube.com/watch?v=Piqjlwh3qR4

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

Looks like everyone walked away from the truck accident.

You're seriously trying too hard now to posts these accidents.

[tradephoric]

Saying that a roundabout forces drivers to slow down is as silly as saying that a red light forces drivers to stop.  Yes, someone can post videos of drivers blowing through red lights too, but a driver blowing through a roundabout without slowing can be extremely dangerous.  WARNING!  These are graphic videos of serious roundabout crashes.

https://www.youtube.com/watch?v=Piqjlwh3qR4

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

Looks like everyone walked away from the truck accident.

You're seriously trying too hard now to posts these accidents.

You are right Jeff, it was reported that nobody was seriously injured in the accident and the victims were taken to hospital with only cuts and bruises. 
https://www.newsflare.com/video/206128/crime-accidents/motorcyclists-escape-death-after-truck-smashes-into-traffic-island-and-flattens-them

In researching the crash i had accidentally typed "May 15 2008 Cambodia roundabout crash" (instead of May 15, 2018 which is the timestamp in the video).   The first google result was a news headline about a bus in Hong Kong that lost control in a roundabout in 2008 and killed 18 people.  According to the article it was the worst traffic accident in Hong Kong in 5 years.

A bus driver was being held for questioning by police last night after Hong Kong's worst traffic accident in five years left 18 people dead and 44 injured - including a dozen who were fighting for their lives.  The bus, carrying worshippers to the monthly gathering of a religious sect, went out of control at a Sai Kung roundabout, flipped on its side and rammed into a noise barrier. The roof was crushed and seats bent, trapping the dead and injured.
https://www.scmp.com/article/636047/speeding-blamed-bus-crash-kills-18

https://www.youtube.com/watch?v=l1ALGjaVyOE

[jakeroot]

To summarise the two sides here:

- You can fuck up at a signal and get away unscathed, but
- You can't fuck up at a roundabout and get away without at least some property damage.

There are 3035 signalized intersections in Chicago proper, with its population of 2.705 million. That works out to one traffic light for every 891 residents. Dividing that by the population of the US (325.7 million), and you get 365,544 signals. That's very sketchy math, but it's the best I can do right now. According to Trade, there are about 6000 roundabouts in the US.

Your estimate sounds pretty close Jake.  In 2007 the FHWA estimated that there were about 311,000 traffic signals in America and at that time there were about 301 million people in America.  That turns out to be one traffic light for every 967 residents.  Assuming that same ratio, at 325 million people there would be about 336,000 traffic signals today.  The FHWA might estimate the total number of roundabouts at 4000-4500 as they probably wouldn't consider all the private subdivision roundabouts in that database i linked; and rather focus on city, county, and state roundabouts.  Out of 100 traffic signals, if one or two of them are converted to roundabouts that seems reasonable and nationally that's the ratio we are seeing.  But you look at a place like Carmel, where 90% of the traffic signals are being converted to roundabouts, they are coo coo for cocoa puffs. 

Rarely is my "estimation" math correct, so I'm glad I was on the right track here.

[kalvado]

To summarise the two sides here:

- You can fuck up at a signal and get away unscathed, but
- You can't fuck up at a roundabout and get away without at least some property damage.

The main selling point is different, though
- You can fuck up at a signal and get away unscathed, or your dead body may be hauled from the accident scene. but
- You can't fuck up at a roundabout and get away without at least some property damage, but chances are you will live to report that to your insurance

[jakeroot]

To summarise the two sides here:

- You can fuck up at a signal and get away unscathed, but
- You can't fuck up at a roundabout and get away without at least some property damage.

The main selling point is different, though
- You can fuck up at a signal and get away unscathed, or your dead body may be hauled from the accident scene. but
- You can't fuck up at a roundabout and get away without at least some property damage, but chances are you will live to report that to your insurance

Very true.

[DaBigE]

The main selling point is different, though
- You can fuck up at a signal and get away unscathed, or your dead body may be hauled from the accident scene. but
- You can't fuck up at a roundabout and get away without at least some property damage, but chances are you will live to report that to your insurance

Depends on your definition of fuck up. Is fucking up using the incorrect lane or is it attempting to go straight thru the central island? Can "near misses" be classified as fuck ups? Based on those definitions, I'd say it is possible to fuck up at a roundabout and get out unscathed.

[jeffandnicole]

The main selling point is different, though
- You can fuck up at a signal and get away unscathed, or your dead body may be hauled from the accident scene. but
- You can't fuck up at a roundabout and get away without at least some property damage, but chances are you will live to report that to your insurance

Depends on your definition of fuck up. Is fucking up using the incorrect lane or is it attempting to go straight thru the central island? Can "near misses" be classified as fuck ups? Based on those definitions, I'd say it is possible to fuck up at a roundabout and get out unscathed.

If you don't live, tradephoric will find the news story and publish it here!

[kalvado]

To summarise the two sides here:

- You can fuck up at a signal and get away unscathed, but
- You can't fuck up at a roundabout and get away without at least some property damage.

The main selling point is different, though
- You can fuck up at a signal and get away unscathed, or your dead body may be hauled from the accident scene. but
- You can't fuck up at a roundabout and get away without at least some property damage, but chances are you will live to report that to your insurance

Very true.

Maybe yes, maybe no. Roundabout under my window had 0 fatalities in 10 years before being built, and 1 - or may be 2 - in 10 years since built.

[jakeroot]

To summarise the two sides here:

- You can fuck up at a signal and get away unscathed, but
- You can't fuck up at a roundabout and get away without at least some property damage.

The main selling point is different, though
- You can fuck up at a signal and get away unscathed, or your dead body may be hauled from the accident scene. but
- You can't fuck up at a roundabout and get away without at least some property damage, but chances are you will live to report that to your insurance

Very true.

Maybe yes, maybe no. Roundabout under my window had 0 fatalities in 10 years before being built, and 1 - or may be 2 - in 10 years since built.

I'm just saying, that is indeed the reasoning. The "few" crashes that would potentially occur, would be relatively low impact. Just seems that, there weren't many fatal crashes at most signals before anyway. And roundabouts are by no means immune for fatalities.

[jakeroot]

The main selling point is different, though
- You can fuck up at a signal and get away unscathed, or your dead body may be hauled from the accident scene. but
- You can't fuck up at a roundabout and get away without at least some property damage, but chances are you will live to report that to your insurance

Depends on your definition of fuck up. Is fucking up using the incorrect lane or is it attempting to go straight thru the central island? Can "near misses" be classified as fuck ups? Based on those definitions, I'd say it is possible to fuck up at a roundabout and get out unscathed.

(Didn't see this)

Fucking up, in my context, was not being aware of one's surroundings while approaching a junction. If you don't take evasive maneuvers when approaching a roundabout, it's nearly impossible to avoid hitting the central island. Even if you walk away without injuries, there's a good chance you car will have sustained a least a few scuffs. Or you could hit one of those statues like they have in Europe, and be guaranteed a collision. With a signal, you could (theoretically) pass through the junction, just like you would any unsigned/unsignalized junction, without hitting anything or anyone.

We should really consider dropping the "low speed" requirement for "modern roundabouts".

I can almost guarantee that will never happen. There is a direct relationship between speed and amount of injury. Lower speeds and traffic "calming" have been high on the list of benefits of modern roundabouts since the beginning. Raise the speeds and your pretty-damn close to the rotaries that many are trying get rid of.

Overall, there's still a huge educational gap with roundabouts, especially multilane versions. FYAs aren't much different in that regard, but are arguably more intuitive to the new user. Consider this: there are 19 states that do not require formal driver education, according to the Washington State Legislature. We have new drivers in 19 states largely basing their driving habits on their parents or guardians and what they see in GTA. Even in the states that do require formal driver education, roundabouts still aren't necessarily part of their DE's manuals.

How solid is the evidence that rotaries are more dangerous than modern roundabouts? I keep seeing this comparison, between rotaries of yore and modern roundabouts, but the biggest issue with so many of those was the lack of [good] lane markings, poor signage, weaving, and uneven yielding (sometimes yielding in circle, usually not). Besides, even the largest rotaries (like the one in Revere, Mass) only allow maybe 55 mph (speeds could be reduced there by signalizing it). And that's at the top end. One of the better rotary-turned-roundabout's is certainly Latham Circle, in NY. Great markings certainly make it operate much more safely than before, even though it's still quite large.

Perhaps more importantly, how many rotary crashes are/were related to speed?

[kalvado]

Perhaps more importantly, how many rotary crashes are/were related to speed?

Any flipped truck within roundabout is a combination of uneven surface and speed - albeit possibly very low - being too high.

[ET21]

What is known as the Suicide Circle, this roundabout is currently undergoing a big face-lift. I drive through it everyday now since I moved and this project is pretty expansive. It involves completely redoing the roundabout to more safer standards, turning a local business street (Broadway) into a boulevard, and redoing the intersection of Broadway street with Northwest Highway (US-14) to the south.

OG roads before construction: https://www.google.com/maps/@42.0527219,-87.9097305,376m/data=!3m1!1e3

Plan for the circle (Before and after): http://hbmengineering.com/blog/transportation-design/cumberland-circle-roundabout/