Crash prone 'modern roundabouts'

[jakeroot]

I know of roundabouts that have rumble strips in advance, but they're all in rural locations.  Here's an example on US-50 in Kansas.

Not aware of any in urban settings.

Interesting. I wish the rumble strip was placed a little later, though (and a bit more often, rather than just once). Speed limit 55, with only one rumble strip, doesn't seem adequate.

There is more than one set of rumble strips.  Go west two or three mouse clicks, and you'll find another one.  And the speed limit along US-50 is 65 mph, by the way.  55 is just the reduced speed limit approaching town.

Oh, I found them. Didn't think there'd be more in that direction. Still would like to see more closer to the actual roundabout.

According to this sign, placed opposite a 65 mph speed limit for southbound traffic (heading away from the roundabout), the limit approaching the roundabout is 55: https://goo.gl/LPGY55

[billpa]

You can joke about seeing blood everywhere but Cassi Lam isn't laughing.

What's wrong with you?
I was commenting on the video you posted, nothing else.

SM-T230NU

[jakeroot]

You can joke about seeing blood everywhere but Cassi Lam isn't laughing.

What's wrong with you?
I was commenting on the video you posted, nothing else.

In a last ditch effort to win over the more easily-influenced of us, tradephoric has turned to the Helen Lovejoy, "think of the children" style of arguing.

All engineers have blood on their hands. Even the safest of intersections have probably had a bad accident at one point, where someone was hurt. You can prevent 99% of collisions, but there will always be that 1% that you just have no control over. I'm not saying Cassie Lam's accident is one of those cases, but you just can't take these things personally.

[kalvado]

You can joke about seeing blood everywhere but Cassi Lam isn't laughing.

What's wrong with you?
I was commenting on the video you posted, nothing else.

In a last ditch effort to win over the more easily-influenced of us, tradephoric has turned to the Helen Lovejoy, "think of the children" style of arguing.

All engineers have blood on their hands. Even the safest of intersections have probably had a bad accident at one point, where someone was hurt. You can prevent 99% of collisions, but there will always be that 1% that you just have no control over. I'm not saying Cassie Lam's accident is one of those cases, but you just can't take these things personally.

There should always be a balance between taking too much personal responsibility vs. ignoring personal aspect at all. From my perspective, we shifted toward too much of chapter 11 when CEO walking out of the window or eating bullet would be more appropriate due to total clusterfuck on their watch. For example, Katsuaki Watanabe - chairmen of Toyota during "sticky mat" fiasco,  still works for Toyota.

I don't know if I would be able to sleep well if something I designed would result in a fatal accident - but apparently any car/airplane/traffic designer knows that will happen, sooner or later. Then statistics may come to help - if there will be less of those events, it should be sort of OK.
Now, looks like numbers don't add up for some of those circles... And I am not sure how designers should feel in such situation. "I was just doing my job"? Oh, well...

[billpa]

Now, looks like numbers don't add up for some of those circles... And I am not sure how designers should feel in such situation. "I was just doing my job"? Oh, well...

It depends. Not all crashes are created equally. There's a lot of distracted driving these days and I'm not convinced that's not playing a role in some of what's being offered here.
I've not read every post in this thread but I've seen some links to stories of drunk drivers or speeders. The OP likely wouldn't blame the design of a four-way traffic controlled intersection if a drunk driver blew through a functioning red light.



HTC6525LVW

[kalvado]

Now, looks like numbers don't add up for some of those circles... And I am not sure how designers should feel in such situation. "I was just doing my job"? Oh, well...

It depends. Not all crashes are created equally. There's a lot of distracted driving these days and I'm not convinced that's not playing a role in some of what's being offered here.
I've not read every post in this thread but I've seen some links to stories of drunk drivers or speeders. The OP likely wouldn't blame the design of a four-way traffic controlled intersection if a drunk driver blew through a functioning red light.

And these are probably the worst possible excuses for the engineer to make. But oh, well, Roger Boisjoly is dead - and probably forgotten. And Toyota still sells.

[jeffandnicole]

I don't know if I would be able to sleep well if something I designed would result in a fatal accident - but apparently any car/airplane/traffic designer knows that will happen, sooner or later. Then statistics may come to help - if there will be less of those events, it should be sort of OK.
Now, looks like numbers don't add up for some of those circles... And I am not sure how designers should feel in such situation. "I was just doing my job"? Oh, well...

There's a huge difference in a design flaw that killed someone, and an accident that just happened to kill someone in an intersection you designed.

Design flaw: Car approaches an intersection with driver who can't see the traffic light. Runs red light. Kills innocent motorist. Bad design.

Not a design flaw: Car approaches intersection with driver high on meth and cocaine. Runs red light.  Kills innocent motorist. Bad driver.

If you can't go to sleep at night over the latter, you would need to find another line of work.

[cjw2001]

Nice to see some sanity in the thread.   Meanwhile the city of Carmel continues to open new roundabouts at a rapid pace, with lots of happy drivers from reduced congestion and no mass carnage. 

[tradephoric]

Nice to see some sanity in the thread.   Meanwhile the city of Carmel continues to open new roundabouts at a rapid pace, with lots of happy drivers from reduced congestion and no mass carnage. 

Carmel drivers are guaranteed to experience some delay when traversing through a roundabout.  That's not the case with traffic lights.  Last night I literally drove 40 miles without getting stopped at a signal — driving through 122 consecutive green lights.  Zero delay while traveling through 122 green lights.  That could never happen at roundabouts. 

[kalvado]

I don't know if I would be able to sleep well if something I designed would result in a fatal accident - but apparently any car/airplane/traffic designer knows that will happen, sooner or later. Then statistics may come to help - if there will be less of those events, it should be sort of OK.
Now, looks like numbers don't add up for some of those circles... And I am not sure how designers should feel in such situation. "I was just doing my job"? Oh, well...

There's a huge difference in a design flaw that killed someone, and an accident that just happened to kill someone in an intersection you designed.

Design flaw: Car approaches an intersection with driver who can't see the traffic light. Runs red light. Kills innocent motorist. Bad design.

Not a design flaw: Car approaches intersection with driver high on meth and cocaine. Runs red light.  Kills innocent motorist. Bad driver.

If you can't go to sleep at night over the latter, you would need to find another line of work.

Sure, dehumanizing coupled with ignorance in statistics can go a long way..

[billpa]

I looked up the Cassie Lam case.

"Child found that Lam stepped into a crosswalk at the last second without signaling her intent to cross and without giving the driver time to stop. The empty bus was not speeding."

SM-T230NU

[tradephoric]

^^Cassi was just one of two girls to get hit in the crosswalk shortly after the Homer Watson/Block Line roundabout opened... the other being an 11 year old girl who was hit while riding her bike in the crosswalk.  Everybody knows you aren't supposed to ride your bike across the crosswalk so we can ignore her injury crash too.  Of course if we ignore every crash where someone was found to be at fault, then there wouldn't be a crash problem at these roundabouts.  Hmmm... I think you just solved the problem!  Just ignore all these crashes. 

Maybe I'm humanizing these crashes because you seem to ignore the cold hard facts.   The fact is the Homer Watson/Block Line roundabout had 435 crashes over a 5 year period - a whopping 257 more crashes than the next closest intersection in the region.  The fact is the Homer Watson/ Block Line roundabout averaged 10.2 injury crashes per year, about the same average injury crashes as the most dangerous signalized intersection in the region (even as the signalized intersection carried much higher traffic volumes than the roundabout).  The fact is the Homer Watson/Block Line roundabout was deemed the most dangerous intersection in the region of Waterloo with an average excess social cost of $271,780.

[billpa]

You cannot blame a roundabout for a teen walking right in front of an oncoming bus. You chose to raise this case to further your argument and to take a dig at me. No one forced you to point out the Cassie Lam story.

SM-T230NU

[kalvado]

You cannot blame a roundabout for a teen walking right in front of an oncoming bus. You chose to raise this case to further your argument and to take a dig at me. No one forced you to point out the Cassie Lam story.

SM-T230NU

As someone who had to cross a road by roundabout a few times:
you SHOULD blame roundabout for any pedestrian accident. Moreover, roads SHOULD be driven - and  designed - with irresponsible kids in mind.
I remember a video they showed during mandatory pre-license class: what kind of unexpected road hazards driver has to anticipate. Kids, pets, animals running into the road are a big issue - and if you see them roadside, keep an eye on them.
And to add insult to injury - roundabouts don't allow that monitoring, in fact view to the other side is often deliberately blocked, hence they are part of the problem.

[Rothman]

If all roads were designed with irresponsible kids in mind, then they would all be fenced off and have a speed limit of 10. You can't eliminate incidents due to stupidity.

No, the roundabout is not at fault when a kid just steps out in front of a vehicle.

[kalvado]

If all roads were designed with irresponsible kids in mind, then they would all be fenced off and have a speed limit of 10. You can't eliminate incidents due to stupidity.

No, the roundabout is not at fault when a kid just steps out in front of a vehicle.

If roads were not designed with stupid kids in mind, we would have speed limit of 65 on city streets.
Roundabout may not be the cause of that kid action; but it creates certain traffic - vehicular and pedestrian - patterns, and certain (in)visibility areas. One isolated accident may - or may not - occur with traffic light instead of roundabout; this is all about statistics.

[Rothman]

By your logic stemming from the kid getting by the bus, crosswalks should be done away with as well.

[jeffandnicole]

One isolated accident may - or may not - occur with traffic light instead of roundabout; this is all about statistics.

That's what we've been saying all along.

[kalvado]

By your logic stemming from the kid getting by the bus, crosswalks should be done away with as well.

Did you ever use crosswalk by the round about? If you want, I invite you participate in a test on a local one.  PM me for phone number, we can meet and try out the funny one in Albany.  I'll  do my best to ensure you survive that experience, although that is definitely not a given.

Roundabouts and crosswalks just don't match, like party balloons and sewing needles.

[kalvado]

One isolated accident may - or may not - occur with traffic light instead of roundabout; this is all about statistics.

That's what we've been saying all along.

Yep, and numbers show roundabouts are heavily overrated.

[tradephoric]

You cannot blame a roundabout for a teen walking right in front of an oncoming bus. You chose to raise this case to further your argument and to take a dig at me. No one forced you to point out the Cassie Lam story.

Neither a signalized intersection or roundabout is immune to drunk drivers, distracted drivers or kids running out into the crosswalk.   All i know is we have been told that roundabouts are suppose to reduce injury crashes.  When that doesn't happen i question why.  Cassi Lam's injury happened in 2011 and the 2016 region of Waterloo collision report analyzes crash data from 2012-2016.  Even without her injury analyzed, the Homer Watson/Block Line roundabout was the most dangerous intersection in the region over the past 5 years.  There are literally hundreds of signalized intersections in Kitchener and Cambridge (which makes up the region of Waterloo) yet the title for the most dangerous intersection goes to a roundabout.  What a prestigious award!

In addition to the Kitchener roundabout, a published report out of Minnesota looked at six 2x2 roundabouts and found that INJURY crashes increased by 6.3%.  In addition PDO crashes increased by 212.5%.  That's pretty much in line with what i have been arguing throughout this thread.  For all this time we have been told roundabouts reduce injury crashes, recent studies are starting to dispute that common believe in regards to these complex roundabouts.  It doesn't appear all types of roundabouts reduce injuries (and they sure as hell don't reduce PDO crashes!.. those go through the roof). 

[billpa]

Neither a signalized intersection or roundabout is immune to drunk drivers, distracted drivers or kids running out into the crosswalk.

But you don't bang on about those. 
For you, if someone gets hit crossing at a light it's the fault of the driver or the pedestrian or a combination of the two. 
If they get hit crossing at a roundabout then it's the roundabout's fault.

[kalvado]

Neither a signalized intersection or roundabout is immune to drunk drivers, distracted drivers or kids running out into the crosswalk.

But you don't bang on about those. 
For you, if someone gets hit crossing at a light it's the fault of the driver or the pedestrian or a combination of the two. 
If they get hit crossing at a roundabout then it's the roundabout's fault.

There is a so-called "swiss cheese model" for accidents: https://en.wikipedia.org/wiki/Swiss_cheese_model
Any accident in a properly designed system is a result of multiple failures. That is, of you stack a few slices of swiss cheese - chances are you are not having any through holes. Or the holes may align..

In case of pedestrian-car accident, there are driver who should pay attention, pedestrian who should pay attention, road design which should favor proper behavior of both, police presence to help those folks behave, speed limits which increase time to react and reduce injury, deformable car exterior which absorbs collision energy and reduces injury - and so on.
A fatal accident means too many of these issues came up at the same time. And we must examine role of each and every factor. Kid not paying attention? check. Driver not paying attention? Possibly. Roundabout inflicting lower speed? check. Roundabout preventing driver from seeing pedestrian? check.  Bus not responding properly to collision? possibly - etc.

Saying roundabout (signalized intersection, crosswalk layout) is not relevant to the accident is plain wrong. It may worked as designed - or not worked as designed; but you need to crunch the numbers to be certain. If intersection A does better than intersection B - if other factors are equal - then it is about design.
Since no structures are truly equal, it boils to more statistics and analysis.. Yet that is the overall logic

[TheHighwayMan3561]

What exactly is the continued purpose of this thread? Will posting enough articles about roundabout accidents somehow prevent future ones from being built? What actions are you guys taking other than cruising google for articles that fit your views and saying it proves you right? Do you deliberately avoid any roads that have them in use?

[kalvado]

What exactly is the continued purpose of this thread? Will posting enough articles about roundabout accidents somehow prevent future ones from being built? What actions are you guys taking other than cruising google for articles that fit your views and saying it proves you right? Do you deliberately avoid any roads that have them in use?

Well, what is the purpose of any internet discussion?  Same here.

Talking for myslef: no, I cannot avoid roundabouts - I cannot get easily from home without driving through one (other options are cutting through corner gas station or 5 miles of back roads to next highway exit, about 10 minutes extra drive). The only entry to work is through roundabout; my wife has to navigate at least 2 - and up to 6 - to get to her. We both believe traffic lights would be a better solution for the area.

Single crashes reports are moot; but there is enough higher level analysis posted here to question unrestricted roundabout ideology.

As for what else can be done.. Maybe not related - but the party which pushed for local flood roundabouts lost some local offices after forcing through a quite controversial batch. Although that didn't make NY battleground state as Trump wanted - county voted red last year. Is that related? Maybe yes, maybe not. But no new roundabout construction is planned..