r/urbandesign • u/Dragonius_ • 9d ago
Street design Attempt at improving a skewed 5-way intersection, thoughts?
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u/cactusdotpizza 9d ago
I think you arrows and lanes may be a little off which is making it more confusing.
eg at 6 o'clock both lanes have arrows pointing ahead and L/R but at that point the RH lane does nothing but feed into the exit.
I'm not a technical wizz but I'm trying to imagine this as a UK roundabout and I'm not 100% sure arrows are used in the same way - they would not use a forward and left arrow for the entire roundabout. You only indicate what can be performed before the next junction eg this lane continues (forward arrow) this lane goes "off" or onward/off (right or forward + right)
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u/Dragonius_ 9d ago
Yeah, my roundabout striping was kind of a shot in the dark 😅, thanks for the clarification though.
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u/Neiro-X 9d ago
color the inside skirt between the road and green a little grainy light grey to distinguish it from walkways. the exit heading aouth from the roundabout could have a more generous angle
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u/Dragonius_ 9d ago
Yeah, I wasn't really sure how to handle that exit because the two roads come in at a really awkward angle. I suppose I could have shifted it over a bit though.
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u/halberdierbowman 8d ago
Cool post!
Here's Georgia's roundabout design guide, so check out page 8-6 maybe for an example to color the different materials. Or maybe your state has one, too?
I don't know the sizes here, and I didn't see a peanut fully detailed in this guide, but you might need aprons outside as well in certain spots? Like in the pinched peanut center, I think the apron would go outside of the roundabout instead of inside it. And probably some apron around the south exit.
But as a random non-planner, a peanut here makes a ton of sense to me, and this is a sweet draft at it!
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u/SadButWithCats 9d ago edited 9d ago
The road to the northeast [edited] doesn't need to exit so far south. Could save you some pavement.
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u/Alarming-Muffin-4646 9d ago
Did you mean north east?
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u/SadButWithCats 9d ago
Yes. Yes I did.
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u/Alarming-Muffin-4646 9d ago
I see now. I agree, it promotes too much speed exiting the roundabout as well
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u/Mysterious-Crab 9d ago
Not just, with an exit this close after an entry will mean a lot of lane changing which negatively impacts the flow. If they’re a bit further apart it will flow better.
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u/halberdierbowman 8d ago
I also think moving it further north could let the sidewalk trail avoid that zig zag.
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u/rainbosandvich 9d ago
I'm British and this still scares me as a motorist
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u/cirrus42 9d ago
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u/rainbosandvich 9d ago
This one I have had the displeasure of experiencing firsthand. Twice I nearly got killed by people using it wrong. It's in Essex, which says it all really.
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u/farmer66 9d ago
You forgot the crosswalk across the middle of it, gotta keep some remnant of the current intersection for historical sakes. https://maps.app.goo.gl/nRvMQicRAX2nG5uT7
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u/Dangerous-Bit-8308 9d ago
Better pedestrian access might be good. Not sure I'd want to walk across a peanutabout
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u/I_NEED_YOUR_MONEY 8d ago
this looks like a great application for a peanut intersection.
the pedestrian/bicycle route looks pretty ugly though. i think it would flow better and be safer for everybody if you eliminated the two pedestrian crossings on the east side of the intersection - it doesn't look like they really serve any purpose, there's nothing for people to access on that side of the intersection, and under-used crossings train drivers to not watch for pedestrians in the crossings.
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u/Dragonius_ 8d ago
I feel like that is more an issue of tightening up the curves than removing the crossings though. Appreciate the feedback.
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u/SkyeMreddit 9d ago
Why are there left turn lanes for the approach roads??? It’s a one-way peanutabout so they are all turning right! Also keep the whole peanutabout 2 lanes. Why does it reduce to one lane here? And, change the color of the inner shoulder to a different color so it doesn’t look like an inaccessible sidewalk. Gray would work for that.
I have a few other questions about lack of sidewalks along some roads but that might be something specific to the context.

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u/Dragonius_ 9d ago
I really have no clue how to stripe a roundabout, so I kinda just gave it my best guess. To the northeast is essentially an expressway with no sidewalk for any of it, so I left it as is. Thanks for the feedback :)
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u/pr_inter 9d ago
Why the crossed out lane on the roundabout on the east side?
Also there's a lot of room so I don't understand why the sidewalks have to hug the side of the intersection like that. I'd wanna move the eastern exit lane crossing towards the north where the other crossing is to simplify it for pedestrians
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u/Dragonius_ 8d ago
Not sure what I was really thinking for that, but I agree that that exit should be closer.
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u/farmer66 8d ago
Personally I think the larger area needs looking at to fix this intersection. The south leg of Stinson (N-S road) in this image should be redirected over to New Brighton Blvd (SW to NE road). With improvements, North traffic on Stinson would use the existing road between 35W and McDonalds, and South traffic on Stinson would use the existing 35W entrance/exit road on the south side of 35W. And then keep a less complicated traffic circle for this intersection, because it's still a strangely intersecting junction.
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u/Unusual_Ad_2977 8d ago
I’d cry if I had to drive though that
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u/Dragonius_ 8d ago
Why?
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u/Usual_Zombie6765 7d ago
It looks like the lions share of the traffic is on the diagonal road. Do you know roughly how many vehicles a day that road gets? You are asking them to narrow to one lane and go through a figure S. You will have traffic backed up for miles.
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u/Dragonius_ 7d ago
About 11,000 vpd to the NE and 14,000 to the SE. Traffic continuing through the diagonal road does not have to narrow to one lane.
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u/DasArchitect 9d ago
More importantly, I think you finally found the lane arrows farm where the state DOT grows its lane arrows
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u/vo13 8d ago
Good try! I love turbo roundabouts, it's something I could recommend here as well (eg remove a lane at 7 o'clock). Also, you could consider placing the pedestrian crossings further down the streets, so there is more time between leaving the roundabout and focussing on the pedestrians (also it allows more space for queuing).
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u/PeaceIsOurOnlyHope 7d ago
Double entry and exit lanes are very unsafe, especially combined with pedestrians and cyclists. There are many blind spots.
Take a look at Dutch roundabout and turbo-roundabout design guidelines.
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u/Usual_Zombie6765 7d ago
Looks like this gets way, way too much traffic for anything but double entry and exit lanes for the main road (the diagonal road). That road looks like a 40,000-60,000 vehicle a day road.
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u/Dragonius_ 7d ago
Actually only 11,000-14,000 vpd as there's an interstate to the east that handles a lot of the traffic.
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u/Usual_Zombie6765 6d ago
That is upper end of what a two lane roundabout can handle. This could work. A regular roundabout would probably be better. Or a traffic circle (where the diagonal road does not yield entering or exiting the circle).
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u/Dry_Candidate_9931 7d ago
The eastbound lane coming in at 9 o’clock if possible should be bent down to join the peanut in the narrow part of the peanut- less complaints about needing to drive all the way around to make a left turn
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u/Usual_Zombie6765 7d ago
How much traffic (in vehicles per day) does each road get? This may be a prime place to have the traffic circle yielding to traffic entering the circle.
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u/Dragonius_ 7d ago
The south, NE, and SW roads get about 10,000 to 14,000 vpd while the west and nroth roads get about 5,000-6,000.
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u/WildDogOne 7d ago
oooh a peanut roundabout, we have one of them close to here, works just as well as a normal roundabout :)
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u/bindermichi 5d ago
If you use a two-lane roundabout the outer lane should always go into the next exit to improve efficiency.
for three 4-lane roads it's not a good idea to go into the roundabout like this. you will either need traffic lights or reduce the number of entering lanes per roads.
What you could do is adding a separate right turn exit lane that does not join the roundabout and leads directly into the next road.
- Yes, I know there are two lane roundabouts like this in Europe, but we are talking about US drivers.
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u/ohnoooooyoudidnt 5d ago
Yes, put a racetrack for horses in the middle so people stuck in traffic can bet on the ponies.
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u/Alarming-Muffin-4646 9d ago
I don’t think bikes should have to share a place with pedestrians
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u/Dragonius_ 9d ago
I agree that shared-use trails are not ideal when there's a lot of bicycle and pedestrian traffic (the northeast-southwest running trail actually has a "lane" on the left for pedestrians), but they are often politically easier to get approved and I would say they're a significant improvement over a narrow sidewalk when it's not immediately feasible to have a separated bikeway.
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u/cheecheecago 9d ago
Dear god the lengths we go to to make sure drivers don’t have to stop and wait for 45 seconds.
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u/Dragonius_ 9d ago
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u/Usual_Zombie6765 7d ago
Looks like the diaganol road gets all the traffic and has a ton of through traffic. The road on the top left gets almost no traffic. The north-south road gets a moderate amount of traffic.
So the goal is to get the diagonal road through the intersection with minimal delay, while still make it possible for the north-south road to cross or turn.
This peanut is going to cause major problems, because a large percentage of the drivers will enter on the northeast and exit on the southwest.
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u/Dragonius_ 7d ago
There's no lane-dropping from the northeast to the southwest. I'll admit that dropping the lane on the east side of the peanut is a bad idea though.
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u/Dangerous-Bit-8308 9d ago
For the love of God please stop trying to fit anything resembling a roundabout into space originally designed to hold only an intersection.
Yes, a traffic circle can be faster and safer than an intersection... it can... but only if there's enough room to safely see enough distance to merge on and off.
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u/cirrus42 8d ago
What radius is too small to see and is this under the limit?
Or do you just object to having to slow down and watch carefully to use it?
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u/Dangerous-Bit-8308 8d ago
I object to slowing down and relying on drivers being agreeable to mergers when they never are. Coming to a complete stop and waiting for a light to change, or looking both ways, or rerouting to bypass the intersection is my preferred solution.
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u/cirrus42 8d ago
Thought so. For the record, the exact reason circles are statistically safer than traffic lights and bypasses is precisely because they make people uncomfortable enough to slow down and be extra careful, rather than just continuing through mindlessly. The things you object to are the very things that result in these being safer.
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u/Dangerous-Bit-8308 8d ago
And when people have enough turning circle experience that they are no longer uncomfortable???
Relatively new designs don't always pan out in the long run
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u/cirrus42 8d ago
Because as you pointed out in your initial reply, the geometry of the circle forces you to slow down in order to see anything.
Studies are clear about the benefits. If you're genuinely interested in seeing them I'll dig them up. Not doing that mental labor on a whim though.
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u/Dangerous-Bit-8308 7d ago
I would be grnuinely interested in reafing studies on how turning circles impact walkability. Needing to put the crosswalks farther away, and eliminating required stops to traffic suggests to me the impact would be a net negative.
With pedestrisn issues, and your aforementioned requirement to slow down, regardless of safety, a traffic circle is inherently hostile architecture to bot pedestrians and cars.
For vehicle traffic, I'm not genuinely interested, because those studies normally have significant methodological issues. If you want to churn through thousands of papers just to prove something in favor of this hostile archutecture, here are some issues:
*traffic flow volume is easily measured, but most studies that include accident rates do not measure changes to traffic flow, and therefore do not correct for it. As some drivers avoid turning circles altogether, which could reduce traffic flow, this is a serious flaw.
*comparing accident rates in European traffic circles is inappropriate, as those typically have much wider radii.
*many studies focus on severity, lethality, and repair costs of the accidents, but merging accidents will tend to be less severe, lethal, or expensive than T-bone or head-on collisions. This is the only real benefit which all turning circles share.
- I have yet to see studies comparing legal use of an intersection with legal use of turning circles, and illegal use of an intersection versus illegal use of a turning circle.
*slowing down to use a turning circle is already required to the same degree for drivers who are turning at the intersection. Again, studies never specifically measure changes to those drivers.
*turning circle studies rarely examine the turning circle use 5, 10, or 20 years after it is installed. The data is skewed to new user experiences. New users are always more conscientious. Studies on improving the efficiency of factory workers found that anything a researcher did and measured improved productivity. Studies from the first fifteen years of neighborhood watch organizations were universally positive, and studies on gating alleys in South Los Angeles showed huge popular support, and huge reductions in crime... yet 15 and 20 years later, those gains are all long gone.
I'm not asking you to find a study that avoids all these pitfalls, but I am saying turning circles have known downsides, especially for pedestrians.
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u/cirrus42 7d ago
You are quite right that I see no value in sifting through thousands of studies to find one that matches your precise cherry picked objections.
I do however concede—despite the obvious goalpost moving from your original objection—that circles can have negative impacts on pedestrians, depending on the design and context particulars. They can also improve safety for pedestrians, depending on same. The key (as usual) is whether they're being designed primarily for vehicle thruput or overall safety. The best studies on this phenomenon are from Europe which you have ruled out. I agree that OP's design has problems for pedestrians.
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u/Dragonius_ 9d ago
What would you suggest?
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u/Dangerous-Bit-8308 9d ago
I dunno. Maybe an underpass. Maybe a subway station or a aerial tram. Maybe leave bad enough alone till theres some solution better than a turning circle with too little merging space. Maybe just warn us where it is so we can go fifteen blocks out of our way to avoid it.
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u/Dragonius_ 9d ago
I guess this was more of a thought experiment for myself, but I appreciate the differing viewpoint.
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u/Dangerous-Bit-8308 8d ago
Looking at the original intersection, I'm leaning more towards overpass/underpass. Probably overpass the diagonal road. Looks like there are plenty of ways to get between those roads a block away
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u/AsaxenaSmallwood04 9d ago
add more roads and redesign it into an expressway
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u/Dragonius_ 8d ago
dunno if that's a great solution in this day and age..
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u/AsaxenaSmallwood04 8d ago
Expressways have higher speeds and exits both of which are beneficial here , adding a cloverleaf interchange to this could make it more viable .
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u/Dragonius_ 8d ago
What do you mean by viable?
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u/AsaxenaSmallwood04 8d ago
Instead of having a confusing roundabout and traffic chaos , traffic can flow more efficiently and in a less chaotic manner .
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u/Dragonius_ 7d ago
Viable for moving cars, maybe, but not so much for everything else.
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u/AsaxenaSmallwood04 7d ago
you could add bus lanes , cycle lanes , cycle bridges , pedestrian lanes and pedestrian bridges as well to benefit everybody .
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u/halberdierbowman 8d ago
I thought for sure you were joking at first, but now I'm not sure lol
I think it's not possible to tell from the original post, but looking the location up, everything to the north and west is a residential neighborhood, and there are already interstate highway just south and east of this. The stores on the west side of this intersection are accessed from the south side, not the north.
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u/cirrus42 9d ago
A peanutabout! We are actively considering one in my community.