Crash prone 'modern roundabouts'

[tradephoric]

I heard there are upwards to 60,000 vehicles per day driving through the Clearwater Beach roundabout during spring break.  That's entirely too much traffic to push through a roundabout in my humble opinion.  You are asking 60,000 drivers to find a safe gap in traffic to enter the roundabout and not screw up.  Here is some great high definition drone footage of the heavily traveled Clearwater Beach roundabout.

[vimeo]https://player.vimeo.com/video/210932002[/vimeo]

[jakeroot]

I heard there are upwards to 60,000 vehicles per day driving through the Clearwater Beach roundabout during spring break. That's entirely too much traffic to push through a roundabout in my humble opinion.  You are asking 60,000 drivers to find a safe gap in traffic to enter the roundabout and not screw up.  Here is some great high definition drone footage of the heavily traveled Clearwater Beach roundabout.

https://player.vimeo.com/video/210932002

There are times when a roundabout may not seem to be a great idea (such as from a technical standpoint), but is the best decision for other reasons. In the case of the Clearwater Beach roundabout, the alternative would be a large signalised intersection that would have to include U-turns (due to the various two-lane intersecting roads). You'd have several signals strung or mounted overhead, creating overhead "visual pollution", and it wouldn't be particularly inviting for pedestrians (not without grade-separated crossings at least).

This may all sound like total rubbish, but when your city exists because of tourism, you have to consider more than just the technical operations of an intersection.

[tradephoric]

There are times when a roundabout may not seem to be a great idea (such as from a technical standpoint), but is the best decision for other reasons. In the case of the Clearwater Beach roundabout, the alternative would be a large signalised intersection that would have to include U-turns (due to the various two-lane intersecting roads). You'd have several signals strung or mounted overhead, creating overhead "visual pollution", and it wouldn't be particularly inviting for pedestrians (not without grade-separated crossings at least).

This may all sound like total rubbish, but when your city exists because of tourism, you have to consider more than just the technical operations of an intersection.

Yeah that's true.  The city was probably more concerned about creating a grandiose entrance to their beach than anything else.  It's just ironic that within a few years of building that grandiose statue in the middle of the roundabout they ripped it out.  While the city may lack foresight, they definitely don't lack money if they can afford to keep revamping the roundabout.

[kalvado]

This may all sound like total rubbish, but when your city exists because of tourism, you have to consider more than just the technical operations of an intersection.

As if half a mile of traffic backup is a better welcome..

creating overhead "visual pollution",

[jakeroot]

This may all sound like total rubbish, but when your city exists because of tourism, you have to consider more than just the technical operations of an intersection.

As if half a mile of traffic backup is a better welcome..

Well, last I checked, most signalised intersections have at least one approach stopped at all times, so a signal wouldn't necessarily be a massive improvement. A major issue here is the number of vehicles, period. There isn't a visually-appropriate option for this junction that would also improve traffic flow. My suggestion? Improve non-vehicle access (being done right now with bus lanes).

At least, with the roundabout, the line of cars is always moving. And, since all the cars (that aren't crashing) are moving relatively slow, you don't have vehicles very loudly pulling away from an intersection (when the light turns from red to green).

There are times when a roundabout may not seem to be a great idea (such as from a technical standpoint), but is the best decision for other reasons. In the case of the Clearwater Beach roundabout, the alternative would be a large signalised intersection that would have to include U-turns (due to the various two-lane intersecting roads). You'd have several signals strung or mounted overhead, creating overhead "visual pollution", and it wouldn't be particularly inviting for pedestrians (not without grade-separated crossings at least).

This may all sound like total rubbish, but when your city exists because of tourism, you have to consider more than just the technical operations of an intersection.

Yeah that's true.  The city was probably more concerned about creating a grandiose entrance to their beach than anything else.  It's just ironic that within a few years of building that grandiose statue in the middle of the roundabout they ripped it out.  While the city may lack foresight, they definitely don't lack money if they can afford to keep revamping the roundabout.

Well, if their statement about maintenance costs is to be believed (fountain being too expensive), that may not necessarily be true. And all things considered, not much has changed at this roundabout for over a decade. Even the out-of-date markings remain from the early 2000s. I see some new signalised pedestrian crossings. Perhaps this may help meter the entrances.

[kalvado]

Well, last I checked, most signalised intersections have at least one approach stopped at all times, so a signal wouldn't necessarily be a massive improvement. A major issue here is the number of vehicles, period. There isn't a visually-appropriate option for this junction that would also improve traffic flow. My suggestion? Improve non-vehicle access (being done right now with bus lanes).

At least, with the roundabout, the line of cars is always moving. And, since all the cars (that aren't crashing) are moving relatively slow, you don't have vehicles very loudly pulling away from an intersection (when the light turns from red to green).

Looking at things from the other perspective - with traffic light, you have a guaranteed time to go through the intersection in terms of queue length and cars per cycle - if there are no downstream problems. Roundabout has no guarantee whatsoever. You can end up waiting tens of minutes (my personal record is 15 minutes being 3 car in line ).  And from my experience , traffic lights handle high traffic better than roundabouts.
Alternatives - I have no idea about traffic pattern, so no opinion about bus lanes. But looking at the satellite photos, sardines in a can have plenty of space compared to that area. My only drive around Tampa area was... well, NYC can be worse on a bad day...

[jakeroot]

Well, last I checked, most signalised intersections have at least one approach stopped at all times, so a signal wouldn't necessarily be a massive improvement. A major issue here is the number of vehicles, period. There isn't a visually-appropriate option for this junction that would also improve traffic flow. My suggestion? Improve non-vehicle access (being done right now with bus lanes).

At least, with the roundabout, the line of cars is always moving. And, since all the cars (that aren't crashing) are moving relatively slow, you don't have vehicles very loudly pulling away from an intersection (when the light turns from red to green).

Looking at things from the other perspective - with traffic light, you have a guaranteed time to go through the intersection in terms of queue length and cars per cycle - if there are no downstream problems. Roundabout has no guarantee whatsoever. You can end up waiting tens of minutes (my personal record is 15 minutes being 3 car in line ).  And from my experience , traffic lights handle high traffic better than roundabouts.

Traffic lights handle high volumes better than roundabouts. I agree with that. But, you can improve the flow of a high-volume roundabout by changing a few things, like metering an entrance.

[Tarkus]

The geniuses behind the MLK Pkwy/Hayden Bridge Road roundabout in Springfield, Oregon that averages ~40 wrecks per year are back at it . . . they're stuffing 5 roundabouts on Franklin Boulevard between I-5 and the Willamette--a road they appear to have cherry-stem annexed.   

On the plus side, they're only 2x1s, unlike MLK/Hayden Bridge, but that second one that seems to intersect absolutely nothing next to the easternmost one (McVay Highway) seems completely pointless.

[ftballfan]

This three-roundabout system at US-23, Old US-23, and Lee Rd in Brighton, MI looks like an accident waiting to happen: https://www.google.com/maps/@42.5062722,-83.7593041,941m/data=!3m1!1e3?hl=en

[jakeroot]

This three-roundabout system at US-23, Old US-23, and Lee Rd in Brighton, MI looks like an accident waiting to happen: https://www.google.com/maps/@42.5062722,-83.7593041,941m/data=!3m1!1e3?hl=en

We've posted about this one before. They're scaling it back, if I recall correctly. One of the older 3-lane roundabouts.

[tradephoric]

This three-roundabout system at US-23, Old US-23, and Lee Rd in Brighton, MI looks like an accident waiting to happen: https://www.google.com/maps/@42.5062722,-83.7593041,941m/data=!3m1!1e3?hl=en

Those roundabouts are accidents that have already happened.  The Lee Road roundabouts had 40 injury crashes from 2011-2016, which is the most injury crashes of any intersection in Livingston County during that six-year time period.  As a comparison, the SPUI at US-23/M-59 carries more traffic than the Lee Road roundabouts yet that intersection didn't even crack the top 5 worst intersections for injury crashes.  As Jake alluded to, they are going to downscale the Lee Road roundabout at a cost of $1.1 million.  Let's just hope the reduced roundabout capacity doesn't cause traffic to back up onto the freeway.

Livingston County's worst intersections for injury crashes
https://www.livingstondaily.com/story/news/local/community/livingston-county/2017/02/10/livingston-countys-worst-intersections-injury-crashes/97607006/

$1.1M project will change crash-prone Lee Road roundabout
https://www.livingstondaily.com/story/news/local/community/livingston-county/2018/01/08/1-1-m-project-change-crash-prone-lee-road-shrinking-3-lane-roundabout-lee-road-reduce-crashes-confus/988173001/

[tradephoric]

The geniuses behind the MLK Pkwy/Hayden Bridge Road roundabout in Springfield, Oregon that averages ~40 wrecks per year are back at it . . . they're stuffing 5 roundabouts on Franklin Boulevard between I-5 and the Willamette--a road they appear to have cherry-stem annexed.   

On the plus side, they're only 2x1s, unlike MLK/Hayden Bridge, but that second one that seems to intersect absolutely nothing next to the easternmost one (McVay Highway) seems completely pointless.

This is somebody getting a hard on for roundabouts and trying to stuff as many as possible in their project.  I agree with you that the roundabout just west of the McVay roundabout seems totally unnecessary.  In the concept picture the roundabout doesn't service any drives so I'm really at a loss the purpose of that roundabout.

[tradephoric]

The Northland and Richmond roundabout in Appleton opened on September 1.  According to Appleton Police there have been 25 reported crashes between August 31st and October 10th.  At the current crash rate, there will be 228 crashes at the roundabout in the first year of operation.  Compare that to 27 crashes in all of 2014 when it was a signalized intersection (the highest crash intersection in Appleton that year).  On the project website, the stated reason the roundabout was selected was to address the high rate of crashes that were occurring at the signaled intersection.  This is the design they came up with.



So after 25 crashes in just 40 days, does anyone still think the roundabout will do a good job at reducing crashes at the intersection moving forward?  While there probably won't be 228 crashes per year, this roundabout could easily see 100+ crashes per year.  Their baseline is 27 crashes, and 100+ crashes is about 4X worse than that.  As long as this roundabout remains a complex 3x2 roundabout next to a busy commercial district, crashes will remain a problem.  But fear not, they will study the roundabout and throw hundreds of thousands of additional dollars to "fix"  the roundabout that they just completed.  Good job.

Crash numbers increase in new roundabout
http://fox11online.com/news/local/crash-numbers-increase-in-new-roundabout

After 155 days of opening, there have been 77 crashes at the new Northland and Richmond roundabout in Appleton (compared to 27 crashes/yr before the roundabout).  At the current crash rate there will be 181 crashes in the first year of operation.  The city is already attempting to "fix" the 155 day old roundabout by adding new signage.  Doubt it will be too effective...my prediction is that in a year or two, the city will eliminate a circulating lane inside the roundabout at a significant cost to the people of Appleton. 

Crashes continue in Appleton roundabout
http://fox11online.com/news/local/crashes-continue-in-appleton-roundabout

Here is drone footage of the newly opened Richmond/Northland roundabout in Appleton.  The complexity of crossing through this roundabout might be equivalent to completing level 1 of Frogger.  Ask 40-50k people (roughly the traffic volume of this roundabout) to complete level 1 of Frogger and see how many misjudge the "gap" and end up with a dead frog.

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

[cjw2001]

What's to learn?  Yield to traffic to left.  Simple as that.   The video shows smoothly flowing traffic.

[Brian556]

Notice the strange yellow markings in this roundabout:
https://www.google.com/maps/place/Weeki+Wachee,+FL/@28.8433589,-82.0165501,93m/data=!3m1!1e3!4m5!3m4!1s0x88e820349a7e9b51:0x3ee81b3447a5426c!8m2!3d28.5155513!4d-82.5728769

[MNHighwayMan]

Looks like the roundabout itself was built for two lanes east/west, but that's it. The western approach definitely can only fit a single lane.

[DaBigE]

Notice the strange yellow markings in this roundabout:
https://www.google.com/maps/place/Weeki+Wachee,+FL/@28.8433589,-82.0165501,93m/data=!3m1!1e3!4m5!3m4!1s0x88e820349a7e9b51:0x3ee81b3447a5426c!8m2!3d28.5155513!4d-82.5728769

Looks like an older roundabout design (or a newer roundabout created by an inexperienced designer), where the central island is kept perfectly circular, despite having an unbalanced number of lanes. The paint is there to [awkwardly] take up the extra space. Here's one of a similar design -- one that falls into the older roundabout category: https://goo.gl/maps/Eq6FqzdHn1K2.

If they were adamant about keeping a perfectly circular central island, they should have left the yellow hatching off and instead pulled the splitter islands inward, creating a more natural path for the single-lane entries.

This is more like what an unbalanced 2x1 should look like: https://goo.gl/maps/C8MFZxqwzaE2

[jakeroot]

This is more like what an unbalanced 2x1 should look like: https://goo.gl/maps/C8MFZxqwzaE2

Of course, if enough asphalt was laid to support a 2x2 layout, marking styles like this would also be appropriate:

[Brian556]

Notice the strange yellow markings in this roundabout:
https://www.google.com/maps/place/Weeki+Wachee,+FL/@28.8433589,-82.0165501,93m/data=!3m1!1e3!4m5!3m4!1s0x88e820349a7e9b51:0x3ee81b3447a5426c!8m2!3d28.5155513!4d-82.5728769

Looks like an older roundabout design (or a newer roundabout created by an inexperienced designer), where the central island is kept perfectly circular, despite having an unbalanced number of lanes. The paint is there to [awkwardly] take up the extra space. Here's one of a similar design -- one that falls into the older roundabout category: https://goo.gl/maps/Eq6FqzdHn1K2.

If they were adamant about keeping a perfectly circular central island, they should have left the yellow hatching off and instead pulled the splitter islands inward, creating a more natural path for the single-lane entries.

This is more like what an unbalanced 2x1 should look like: https://goo.gl/maps/C8MFZxqwzaE2

Its relatively new. I'd say it no more than 10 years old

[tradephoric]

Studies of single-lane roundabouts reported reductions in injury and overall crashes, which typically occur at a slow speed and include side swipes and fender benders and greatly reduce the chance of deadly head-on or T-bone accidents. However, non-injury crashes are sometimes more frequent on multi-lane roundabouts, due in part to driver confusion.
https://www.lmtonline.com/local/article/Statistics-show-roundabouts-safer-than-12816432.php

More fake news.  It's not just about what they report, but what they decide to leave out.  When looking at available crash data, every 2x2 or higher roundabout constructed in America has seen increases in total crashes.  And many of these complex multi-lane roundabouts have also seen increases in INJURY crashes!  Several Dual Lane Roundabouts analyzed in a recent Minnesota study found a 6% increase in injury crashes.  This sentence would have been less propaganda, and more reality. 

"However, non-injury crashes are oftentimes more frequent on multi-lane roundabouts, and sometimes lead to increases in injury crashes" .

[jakeroot]

Smelly incident in Lacey, WA today. Manure truck tipped over in the Pacific Ave/Marvin Road roundabout. Apparently there was a mechanical failure which, combined with the G-forces of the roundabout, caused it to lose its load.



https://twitter.com/theolympian/status/984547950561902592

[tradephoric]

A motorcyclist was killed in Lawrence, Indiana early today after failing to negotiate a roundabout.

Motorcyclist killed in roadway roundabout traffic accident
http://fox59.com/2018/04/13/motorcyclist-killed-in-east-side-roundabout-traffic-accident/

[kalvado]

A motorcyclist was killed in Lawrence, Indiana early today after failing to negotiate a roundabout.

Motorcyclist killed in roadway roundabout traffic accident
http://fox59.com/2018/04/13/motorcyclist-killed-in-east-side-roundabout-traffic-accident/

Seriously, this is just one of 100 fatal accidents which happened yesterday.
Posting statistics makes sense; somewhat special accidents (like manure truck  ) make some sense. Routine crashes... we know that they happen..

[MNHighwayMan]

Posting statistics makes sense; somewhat special accidents (like manure truck  ) make some sense.

It took shitting on roundabouts to a whole new, literal level.

[kalvado]

Posting statistics makes sense; somewhat special accidents (like manure truck  ) make some sense.

It took shitting on roundabouts to a whole new, literal level.

Actually an idea - how about "unusual accidents" thread?
Two candidates in this thread - manure and tar spill; I vague remember accidents involving lots of bees; pigs; coins....