Bad urban planning: Curved intersections.

In August of 2005, I wrote that I’d be perfectly happy blogging about any number of things other than politics. Blogging about politics as an end, rather than a means, isn’t just boring, but I’m not sure that it’s particularly productive. So I’ve decided to make an effort to write more about the sort of things that politics aims to affect and improve. One of the things that I’d be very happy to write more about is urban planning.

The physical structure of our society is a topic that fascinates me. How we arrange our towns and neighborhoods and houses both says a lot about us and strongly affects how we relate to one another. As Charlottesville sprawls out and engulfs Albemarle County, something that I see a lot of is bad planning. Development patterns that discourage socialization, worsen our nation’s reliance on foreign oil, or endanger people’s lives. I intend to write about examples of this periodically.

The topic of today’s post is the new habit of curved intersection corners. One of the worst area offenders on the newly-widened Airport Road, just north of Charlottesville.

Airport Road is, itself, quite a problem. What was a two-lane road connecting Rt. 29 (a major, albeit urbanized, highway) to the tiny Charlottesville/Albemarle Airport is now a four- to six-lane monstrosity. The advertised purpose of this expansion is to create a new multi-modal passageway from the airport to the burgeoning population center right there on Rt. 29. It is, after all, the first road that people see when they fly into town. So there are bike lanes, sidewalks, and businesses are beginning to sprout up along the street. The whole affair is less than a mile long.

But the whole thing doesn’t make any sense. For starters, the 55mph speed limit. Who wants to walk along a sidewalk three feet from 5000lb SUVs whizzing by? Nobody, of course—it’s dangerous. Without lowering the speed limit, creating on-street parking (the line of cars serving as a safety barrier for pedestrians), and planting trees on the grassy strip between the road and the sidewalk (again, a safety barrier), few people are likely to feel safe or even comfortable on the stroll.

For the sake of argument, let’s pretend that pedestrians are going to take this route to Rt. 29. This is where the over-designed intersection comes in. Here are three photographs of where a side street intersects with Airport Road. The first photo is from the perspective of a pedestrian preparing the cross, the second from across the road at an angle, and the third head-on from directly across the road.

Intersection Photo

Intersection Photo

Intersection Photo

The strange thing, as you can see, is that this street corner has no actual corner. There’s only a pair of huge curves. The purpose of these curves are simple: to prevent cars from having to slow down. So on the one hand, cars are presented with a stop sign. On the other hand, the road is clearly engineered to allow them to round that corner at no less than 35mph. Why do people run stop signs? Because they don’t have to stop. Why should they, when all engineering signs point to keep going?

Pedestrians aren’t stupid. A pedestrian facing this street crossing thinks dang, I’m gonna get mowed down if anybody turns in or out of this road while I’m crossing. (Pedestrians who already feel unsafe walking along this road.)

The second problem with this huge curve is the daunting task of crossing it. Walking across a road is not safe. We teach toddlers that they need to be scared when crossing the road. Do so quickly, do so at the narrowest available point, and look both ways while crossing. This intersection shows all the symptoms of having been engineered with crossing in mind. There are crossing pads that are both lowered for wheelchairs, red in color for the visually impaired, and stippled for the blind. Looking at the first photograph, it’s clear that some thought went into the crossing location—pedestrians can’t continue straight down the sidewalk, across the intersection, and onward. Instead they have to curve to the right, cross at the pad, curve to the left, and carry on. Why is that?

Because the curve of the intersection is so huge that the pedestrian would have to spend a dangerously long time crossing the intersection straight through. I paced off this intersection. Crossing at the prescribed location is 21 paces, or about 63 feet. The width of the road itself, before it curves out? Just 9 paces, or about 27 feet. I didn’t pace off the width direct from sidewalk to sidewalk, but I estimate it’s 75 feet.

Engineering curves into this intersection, rather than traditional 90° angles accomplishes just things:

  1. It causes drivers to treat the “stop” sign as a “yield” sign, placing both drivers and pedestrians at risk.
  2. It requires pedestrians to walk 130%-180% farther in a dangerous intersection.

There are no benefits that come of curving the intersection.

So we have a street that pretends to be multi-modal but is clearly designed only for automobiles with intersections that pretend to be accessible and safe but are actually designed to be as dangerous as possible.

The solution? Intersections within the urbanizing areas of the designated growth regions of Albemarle should be required to have 90° corners. Street should be fit into a standard class of the street hierarchy (loop road, boulevard, street, alley) and be engineered accordingly.

Good urban planning isn’t innovative. It consists largely of creating neighborhoods, communities, and even intersections as they would have been designed fifty years ago. That’s not real hard to do.

Published by Waldo Jaquith

Waldo Jaquith (JAKE-with) is an open government technologist who lives near Char­lottes­­ville, VA, USA. more »

12 replies on “Bad urban planning: Curved intersections.”

  1. Waldo,

    I pass through that area regularly and watched closely its development. I also happen to be an urban planning enthusiast, but I take a slightly different take on the matter. I’ve been meaning to write about this particular intersection, so I’ll take the opportunity to elaborate here. The photograph appears to be of the round about near the airport, but it appears to be in the periphery. Am I correct about the location?

    The problem, as I see it, is that the roundabout is the right idea but it is executed poorly. Roundabouts are excellent devices for traffic calming, they are efficient, promote communication among motorists and operate without signal lights, which is most useful during power outages. Probably the largest benefit is that they are safer for motorists and pedestrians than traditional intersections (see

    For all these advantages, this particular intersection is boondoggled by two problems:

    1) excessive signeage — The litany of yields, arrows and miscellany on signs makes an otherwise obvious intersection confusing.
    2) size — It feels about 10% too small and is hard to round the bend. Traffic cricles in Europe are a bit larger and easier to negotiate.

    While I see a lot of value for traditional grid development, in rural areas I think traffic circles are a fine addition, but they need to enlarge them and reduce the visual clutter.

  2. The photograph appears to be of the round about near the airport, but it appears to be in the periphery. Am I correct about the location?

    Actually, it’s not the roundabout, though I can see how you’d figure that. (And I agree with your comments about the roundabout.) It’s just a run-of-the-mill side street, an oddly unnamed one, where one can turn off to go to the mail sorting facility or to a small, brick church.

  3. Here are some things I think are worthy of consideration with regards to the issue you raise:

    -How many pedestrians does that intersection really get?

    -Is there a city bus line that makes a run to the airport? Shouldn’t there be? and Wouldn’t that resolve some pedestrian issues with that intersection?

    -Does the area really get that much traffic?

    There are no benefits that come of curving the intersection.

    Well actually there is one. If you’re driving an overly long vehicle, like a truck or bus, it makes hanging the right hand turn a little easier.

    The observations you make about this intersection may be fair ones. Especially the one about the distance to cross the street. Now with this in mind, I’m thinking about the new “Albemarle Place” development housing/retail center and the distance it will take to cross 29 on foot from Albemarle place to shopping center on the opposite side of 29. There’s plenty of time still to affect change there and, personally I’d vote for an enclosed pedestrian catwalk over 29 as opposed to fighting the temptation to plow thru the jaywalker crossing against the signal, who will be holding up the traffic if a crosswalk were an option they decide on.

  4. How many pedestrians does that intersection really get?

    Presumably, none. Who would want to walk along a street so unsafe?

    Does the area really get that much traffic?

    A fair amount. Anybody going to town from Earlysville comes that way. As more subdivisions go in there, traffic climbs. And, of course, any vehicles going to or from the airport or any of the sizeable employers out that way — USPS, Crutchfield…and a couple of others whose names I can’t recall.

    But it’s hardly thick with traffic. It often was as a two-lane road. Hence the widening, I guess.

    Well actually there is one. If you’re driving an overly long vehicle, like a truck or bus, it makes hanging the right hand turn a little easier.

    Well, sure, in the sense that it makes the turn easier for any vehicle. That’s the problem. :)

  5. I used to bicycle through that intersection occaisionally. Making it easier to drive fast is a bad idea. What we have here is a highway spinning itself as a street, probably to 1) buy off that segment of a public that wants sidewalks, bikeways, etc. or 2) to qualify for funding that requires the installation of sidewalks, bikeways, etc. Or a combination of the two reasons.

  6. There’s a book waiting for someone to write it entitled Walking to the Airport. One of my minor hobbies is walking around in the vicinity of airports when I have a long stopover, and it’s kind of fascinating how different they can be from the pedestrian point of view. There are the huge ones like L.A. International that have been designed (and badly) for the supremacy of the automobile, and that make foot travel like Dante’s progress through the Inferno. There are other large ones like Las Vegas that have decent sidewalks in and out and accessible landscaping (in principle you can walk to the Strip from the airport without risking your life–I must have done about 1/3 of the distance once). I used to live within walking/biking distance of the small airport in Rochester, New York, and it was a reasonable proposition to get there without a vehicle.

    I remember a story about Steve Jobs overseeing the construction of a new house, and complaining when he discovered that the interior of an electrical breaker box had been left bare and ugly–he wanted it painted to match the exterior. The author offered the anecdote as a metaphor for his concern that every part of a design under his responsibility should be just right, no matter how small. The pedestrian/bicycle experience around an airport is that kind of indicator, maybe.

    (Heh. And this all reminds me that one of the least pleasant bicycle trips I’ve ever taken was a misguided ride from the Barracks Rd. area to the Earlysville/airport area way back in 1976 when route 29 was still two lanes in each direction. I’d done a ride up the Coast Highway from L.A. to San Francisco the previous year and thought “terror” meant being passed by a ‘Bago with six inches to spare, but discovered that was fun compared to riding on shoulderless central Virginia roads.)

  7. Okay so we’ve determined that the area isn’t one frequented by pedestrians. In fact for the most part pedestrians really don’t use that area. Not yet anyhow, and if they ever get to a point where they might.. then we will probably be looking at traffic lights (instead of stop signs) and crosswalk lights too.

    In any event thanks for addressing my questions.

    Now I’m going to invite you to focus on “albemarle place.” Where these sorts of issues still need to be addressed and are no less important, but where we still have a chance to shape what happens there. Especially in light of this post from the Hook’s blog ARB approves first phase of albemarle place.

    Now lets focus that attention where we still have a chance to make a difference.

  8. Anybody going to town from Earlysville comes that way.

    Actually, hardly anyone driving to C’ville from Earlysville takes this route. They take Earlysville Road (Rt. 643) to Hydraulic. From Earlysville, and areas beyond, if one were to hang a left at the new light (just past the now defunct Sunnyboy Gardens) and head for the roundabout, then turn towards 29, the result would be to insert oneself right into the worst part of northern Albemarle traffic. Even before all the ridiculous development at Forest Lakes, on the west side of 29, this was a bad route. Taking Earlysville Road all the way in to the Rock Store on the corner of Hydraulic & 643 is how Earlysville folks get to town.

    You’re 100% correct about that curved intersection. One of the beauties of C’ville is that it’s an excellent “walking” town. I used to walk from my home in the Fry Spring’s area to Barrack’s Road, Downtown, UVA — just about everywhere in the city. You’d think that the new “entrance corridor” road from the airport would’ve been more pedestrian friendly, what with all the retail & business development that’s sprung up around Forest Lakes and the big office park a little further north. I certainly wouldn’t want to walk along that road, so close to high speed traffic.

    Is it really 55? I can see 45, but can’t imagine how that road, as short as it is, could be rated for that speed.

  9. Rt. 743, not 643. We called it by the route number for lord knows how many years, until it started being known by an actual name? How quickly we forget.

  10. When I lived in California — two years with a car, three without — I was often the only pedestrian walking through many, many situations like this. I’ve seen sidewalks that end abruptly in the middle of a “block,” intersections that required me to walk 30 feet out of my way to cross, sidewalks that are near-impassable due to nearby sprinklers (for the 1-foot margin of plants between the sidewalk the wall of a gated community), etc. The Santa Clarita Valley got filled up with sprawl at an alarming rate, and it’s a terrible, alienating, ugly, dehumanizing, depressing place. Seeing the same thing happen to Albemarle County is a real shame.

    I agree that it’s not a tough problem to solve– building them like we did 50 years ago sounds about right to me.

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