Crash prone 'modern roundabouts'

[jakeroot]

https://www.youtube.com/watch?v=T83ogwpkfLk

Remember this roundabout being proposed for I-35 and 51st Street in Austin?  Well the roundabout fully opened to traffic on June 14, 2018 and TxDOT released a video showing traffic circulating the new circle.  On August 1, 2018 TxDOT released another video of the roundabout in action and it appears that it has already been downsized from a 3x2 roundabout to a 2x2 roundabout (the spiral inner lane has been striped out).  I couldn't find any articles explaining why the roundabout was restriped but here are the videos TxDOT released:

https://www.youtube.com/watch?v=yuz33HHpq-A

https://www.youtube.com/watch?v=FW98z5LtylU

Interesting that they used used edge markings across that single-lane exit leg on the right. I've only seen that at this roundabout in Federal Way, WA: https://goo.gl/gsYTM9

As it exists now, the right lane to the approach is useless to do anything besides re-enter the frontage road. Which is odd, since they built a ramp for that already. At least before, the two lanes could go left at the roundabout. Now it's, effectively, a single-lane approach.

[jamess]

https://www.youtube.com/watch?v=T83ogwpkfLk

Remember this roundabout being proposed for I-35 and 51st Street in Austin?  Well the roundabout fully opened to traffic on June 14, 2018 and TxDOT released a video showing traffic circulating the new circle.  On August 1, 2018 TxDOT released another video of the roundabout in action and it appears that it has already been downsized from a 3x2 roundabout to a 2x2 roundabout (the spiral inner lane has been striped out).  I couldn't find any articles explaining why the roundabout was restriped but here are the videos TxDOT released:

https://www.youtube.com/watch?v=yuz33HHpq-A

https://www.youtube.com/watch?v=FW98z5LtylU

Every driver in the first video is using that 3rd lane incorrectly, so it makes a lot of sense that they killed it.

Crosswalks look good too. This is an example of a good roundabout Id say

[tradephoric]

^I personally don't foresee a high crash rage at that roundabout especially now that they removed that 3rd lane.  The benefit of the way they got it striped is that trucks can use that pavement area as a truck apron and drivers won't be forced to hop the curbing with their trailer... making it less likely you will see a truck tip-over at this roundabout.  Also interchange roundabouts naturally have simpler turning movements.  If you are exiting the freeway waiting to enter the roundabout, you know that any driver circulating the roundabout is going to continue circulating around it (since drivers can't exit the roundabout at that off-ramp leg... it's one-way).  This prevents the scenario where someone pulls out into the roundabout mistakenly believing that a circulating vehicle was about to exit the roundabout.   In addition, the leg servicing the freeway on-ramp has no drivers entering the roundabout... they can only exit on that leg greatly simplifying operations.  Really high crash rates just aren't seen at interchange roundabout very often (unless if there's some complexity involved like a service drive incorporated into the roundabout design). 

The only thing i don't like about the design is there is a damn retaining wall in the central island.  That wall could easily lead to a fatal crash if someone attempts to blow through the circle at high speed (this picture was obviously taken before the 3rd lane was striped out).  I would not be surprised if in a few years i'm posting a picture of a vehicle that plowed through that retaining wall...

[kphoger]

I personally don't foresee a high crash rage at that roundabout

None of us knows how to respond to this......

[Tonytone]

https://www.google.com/maps/@39.5168107,-75.6803003,1135a,35y,39.2t/data=!3m1!1e3

How will these roundabouts do when heavy traffic occurs? I have drove thru these roundabouts while the highway is not done yet and it's a little tight IMO,

[tradephoric]

https://www.google.com/maps/@39.5168107,-75.6803003,1135a,35y,39.2t/data=!3m1!1e3

How will these roundabouts do when heavy traffic occurs? I have drove thru these roundabouts while the highway is not done yet and it's a little tight IMO,

Those roundabouts have central island diameters of roughly 110 feet.  That doesn't seem that tight as there are many examples of single-lane interchange roundabouts with smaller central island diameters.  For example here is a single-lane roundabout off I-64 near Saint Louis with a central island diameter of just 65 feet:

https://www.google.com/maps/@38.6254184,-90.1345388,64m/data=!3m1!1e3

[tradephoric]

https://www.youtube.com/watch?v=u4oltdv0i9w
^Apart from the RV blowing through the middle of that Worthington Minnesota roundabout, there has been two other pretty major events at the roundabout over the past couple weeks.

Tanker hauling cream overturns in Worthington roundabout

http://www.dglobe.com/news/accidents/4356792-tanker-hauling-cream-overturns-worthington-roundabout


These little piggies almost didn't make it to market when a Minn. hog truck rolled

http://www.agweek.com/news/4350581-these-little-piggies-almost-didnt-make-it-market-when-minn-hog-truck-rolled

Cream trucks rolling over, hogs running around the highway, some RV driver thinking they are Bo Duke... these roundabouts really give the good people of Worthington Minnesota something to talk about!

Another vehicle vaulted over the Worthington roundabout on Sunday.  The driver sustained non-life threatening injuries.  This comes a month after an RV was videotaped launching over the roundabout in early November.

Minivan vaults over roundabout Sunday
https://www.dglobe.com/news/accidents/4375814-minivan-vaults-over-roundabout-sunday

There have been 2 truck tip-over crashes, an RV flying through the middle of the roundabout captured on video, a driver sustaining non life-sustaining injuries after his min-van flew through the middle of the roundabout, and now 4 reported crashes over a few hour period on Friday.  The roundabouts are doing a stellar job at reducing crashes in Worthington.. or maybe they are doing a worthless job.

Snowpacked roundabouts result in four crashes reported Friday
https://www.dglobe.com/news/4380839-snowpacked-roundabouts-result-four-crashes-reported-friday

Yet another semi-rollover happened at the Worthington roundabout Friday morning.

A roundabout rollover

http://dglobe.com/news/accidents/4475427-roundabout-rollover

Another semi loses his load at the Worthington roundabout on Tuesday.  This is at least the 4th semi to tip over/lose their load since October, 2017. 

Spilled grain in Worthington roundabout

http://www.dglobe.com/news/accidents/4479958-spilled-grain-worthington-roundabout

Another semi rolled over at a Worthington roundabout today (October 22, 2018).  One person was taken to the hospital with non-life threatening injuries.  In the past year there has been 5 documented cases of semi trucks tipping over/losing their load in Worthington roundabouts.  Maybe it's time for Worthington to consider ripping these roundabouts out as they just don't seem to be working out too well in their community!

Semi rollover in Worthington injures one
http://www.kkoj.com/news/local-news/semi-rollover-in-worthington-injures-one/

[jakeroot]

For example here is a single-lane roundabout off I-64 near Saint Louis with a central island diameter of just 65 feet:

https://www.google.com/maps/@38.6254184,-90.1345388,64m/data=!3m1!1e3

I can do you one slightly better. This new slightly-oval-ish roundabout in Kelso, WA with an average diameter of 63 feet: https://goo.gl/7sqJHC -- involves three separate freeway ramps.

There is also the Slater Road roundabouts in Ferndale, WA, built within the former grounds of the original freeway ramp terminii. Diameter of ~50-55 feet. They are mountable, near-mini roundabouts though: https://goo.gl/5oHxZQ

Both of these are actually quite nice because, in the event you miss them, you can mostly just sail right over them without hitting anything. Assuming you can maintain control after hitting a curb.

[kphoger]

average circumference

Never heard this term before.

Diameter 63 feet = ICD 20 feet
Am I doing my math right?

[jakeroot]

average circumference

Never heard this term before.

Diameter 63 feet = ICD 20 feet
Am I doing my math right?

*average diameter. Sorry.

[UCFKnights]

So I was debating where to put this post, but Universal Orlando is building new theme parks and the roadway/drainage plans were just released, indicating 2 multi lane roundabouts are going to be built. This obviously will get a load of tourists, tons from out of country, who seem to barely be able to drive as is. Wanted to see what people thought of the 2 roundabouts. One of them is elevated, and only connects 2 roads with the rest of the turning movements being at a signalized intersection below the roundabout, and even includes a bypass ramp to avoid the roundabout in one direction, so a simple ramp would have done a better job for sure, but I guess they want to look fancy?

The other seems to be a more traditional multilane roundabout, here's the plans released so far:

[jakeroot]

That is a very strange elevated structure. Since it only appears to be for one direction, I'm not sure it needs that 3/4-circle look to it; need to see other bits of the plan to be sure.

I see that Universal isn't necessarily going full-Disney and building interchanges at every single node.

[UCFKnights]

Universal doesn't have enough land to do that, there campus has generally been the "urban" version of suburban Disney.

I found a zoomed in image of the "elevated roundabout" and it turns out its not a roundabout at all, just an unneccessarily roundabout shaped ramp where not even all of it is usable. I think the northeast corner of it might be for buses only. Looking for one of the normal roundabout in the plans as well.

[kphoger]

tourists, tons from out of country, who seem to barely be able to drive as is.

In my experience, Americans are generally the least capable drivers on the road.

[webny99]

tourists, tons from out of country, who seem to barely be able to drive as is.

In my experience, Americans are generally the least capable drivers on the road.

I'd say laziest, which isn't quite synonymous with least capable. It's not that American drivers can't keep right on freeways, they just don't. It's not that they can't figure out how roundabouts work most efficiently, they just don't bother. And so on. Our culture is one that encourages laziness and in no place is that more evident than on the road (IMO).

[UCFKnights]

tourists, tons from out of country, who seem to barely be able to drive as is.

In my experience, Americans are generally the least capable drivers on the road.

Perhaps its not entirely based on capability, but the signs and markings are different so their muscle memory will be "wrong". Plus urban American drivers surely have a very different style from rural drivers, which are different from international drivers, creating tons of confusion and a terrible situation.

[jakeroot]

tourists, tons from out of country, who seem to barely be able to drive as is.

In my experience, Americans are generally the least capable drivers on the road.

Perhaps its not entirely based on capability, but the signs and markings are different so their muscle memory will be "wrong". Plus urban American drivers surely have a very different style from rural drivers, which are different from international drivers, creating tons of confusion and a terrible situation.

I'd agree. The lack of markings is definitely odd, especially compared to European countries. We rely heavily on signs, especially text-based ones, whereas Europeans will put a lot of stuff on the pavement (give way triangles, dashed lines for yielding or where to diverge or merge, destinations, etc). There's also right and left on red, which is definitely a foreign concept to everyone not from North America (and also really against all muscle memory). Being able to pass in any lane is also weird, as are the speed limits (usually too low); low limits are OK but seem odd when everyone is ignoring them.

[kphoger]

tourists, tons from out of country, who seem to barely be able to drive as is.

In my experience, Americans are generally the least capable drivers on the road.

Perhaps its not entirely based on capability, but the signs and markings are different so their muscle memory will be "wrong". Plus urban American drivers surely have a very different style from rural drivers, which are different from international drivers, creating tons of confusion and a terrible situation.

I'd agree. The lack of markings is definitely odd, especially compared to European countries. We rely heavily on signs, especially text-based ones, whereas Europeans will put a lot of stuff on the pavement (give way triangles, dashed lines for yielding or where to diverge or merge, destinations, etc). There's also right and left on red, which is definitely a foreign concept to everyone not from North America (and also really against all muscle memory). Being able to pass in any lane is also weird, as are the speed limits (usually too low); low limits are OK but seem odd when everyone is ignoring them.

American drivers disregard striping at a roundabout, or they flat out stop at one until there's nobody even remotely close to possibly heading towards them, because they are incapable of using common sense when confronted with something out of the ordinary.  Send an average American driver around the Arc d'Triomphe (which lacks striping, BTW) and it's a recipe for disaster.  I still maintain that foreign drivers are better equipped to handle unusual circumstances and make a good judgment call than we American drivers are.

[jakeroot]

I was referring to all roads, not roundabouts. In fact, roundabouts are typically the most well striped of any intersection type in the country. Many new striping standards were introduced with roundabouts.

[billpa]

We do have very lazy striping standards in much of the US. Roundabouts are the exception. But in many areas lines just 'end' at intersections, only to resume on the other side.
Lane assignments often come with painted arrows in turning lanes but are blank for lanes where you continue straight ahead.
Some highway exit neutral zones are filled in with chevrons, many are not, who knows what the reason is from one example to the next.

Pixel 2

[kphoger]

My observation is based on drivers from both countries with better signage (Mexico) and striping standards than ours and those with worse standards (western Europe).

[webny99]

I still maintain that foreign drivers are better equipped to handle unusual circumstances and make a good judgment call than we American drivers are.

I actually fully agree, but that isn't because we're incapable. Rather, it's because of the abundance of rules and standards governing our road network mean there rarely is any unusual circumstances. That is to say, the average driver probably won't encounter anything on their commute today they didn't encounter yesterday. Which makes them a bit inattentive after a while. Not so much in other countries, where standards are more lax and you're expected to make decisions on the fly. We don't have to do that here, largely because of the higher standards and very well-established expectations (probably too much so - leading to perceived inability to handle unique situations).

[jamess]

Just came back from Amman, which is packed to the brim with roundabouts...

American drivers are angels and scholars

[kphoger]

Just came back from Amman, which is packed to the brim with roundabouts...

American drivers are angels and scholars

Perfect addition to the discussion!
If you plopped 200 American drivers down in Amman, how many of them do you think would have a traffic accident within the first week?
That's what I mean by incapable.

[kalvado]

Just came back from Amman, which is packed to the brim with roundabouts...

American drivers are angels and scholars

Perfect addition to the discussion!
If you plopped 200 American drivers down in Amman, how many of them do you think would have a traffic accident within the first week?
That's what I mean by incapable.

If you plopped 200 off-the-street americans into an every day life of third world country, how many of them would make it till the end of the week? Doesn't make people incapable or unfit for life.

Jordan has 151 accident/year  per 100k vehicles vs 13 in US - about 12 times higher accident rate. Of course, NASCAR would have an even higher accident rate - and even more skilled drivers.. But for last  10 year I mostly drive to get from point A to point B in one piece...