Earlier this year, the Harvard Business Review blog briefly featured a study that compared a neighborhood of suburban Woodinville to one in urban Ballard. The blue lines in the graphic above illustrate the 1 kilometer reach of a pedestrian walking from the red dot in the center. This so-called walkshed is an important measure of ability from one to get from point A to B and helps us explain why one who lives in Ballard is more likely to walk to the grocery store or the local park than one in Woodinville.
The graphic also explains to us why transit ridership in Ballard is likely to be much higher than ridership in Woodinville, and why Woodinville has more driving. The study notes that those who live in communities like the Ballard neighborhood above drover 26% fewer miles than those in cul-de-sac-based communities.
Some cul-de-sacs are better than others, of course. Some suburban communities have cut-throughs that allow pedestrians and bicyclists to reach arterial streets and other roads efficiently. Most frequently, however, the paths available to pedestrians in suburban communities are the same twisty, maze-like roads that cars navigate. When developers don’t afford pedestrians an efficient means of getting around, it’s no surprise that many suburbs turn to auto-dependency.
We’ve spoke about the benefits of the urban street grid (and its political effects) before. Other reactions on the walkshed study are available at Infrastructurist and Human Transit.
55 Replies to “The Damaging Effect of Cul-de-sacs on Walkability”
So the question is: as walkability advocates, what can we do about it?
We’re not going to get developers to change their policies by education alone: cul-de-sacs layouts often support more buildable lots and also raise property values: most people seem to feel that they are safer and their kids are safer on a street with less traffic. (They’re probably even right from a narrow standpoint: in a community with arterials and cul-de-sacs, cul-de-sacs are much less trafficked. Compared against a grid system, I’m not so sure)
Could we lobby suburban governments? Would Redmond, for example, see it as being in their interest to mandate a grid for future developments? What about a less developed suburb, say, Marysville?
I’m not sure that cul-de-sac’s generate more lots, but there’s an easy fix regardless.
All that needs to happen is to lay over a cul-de-sac layout pedestrian/bicycle connections from each dead end to the next street. A well connected network can be accomplished that encourages walking and biking, while maintaining the actual (or perceived) benefits of street discontinuity reducing through traffic.
Is there a walkshed map of a cul-de-sac community with these connecting paths? I would like to see that.
Reminds me of being a little kid in the suburbs of St. Louis taking shortcuts through the yard of that cranky guy who spent his days glaring at children. I wish I could go back in time and tell him I was just improving my home’s walkshed…
Might not be that clear from this overhead map
But this is a typical neighbourhood in Sweden. At the end of each street there is a small paved path for pedestrians and bikes.
This is more or less standard for building housing in Sweden. We very seldom build in squares and we have almost always paths for pedestrian. On the left side of the map just to the right of the road named Korpardalsvägen you can make out a playground which is also common for these types housing areas in Sweden. A large part of the idea is to get children of the streets with large amounts of traffic.
To that effect there are also lots of bike paths next to many of the larger roads in Sweden. One can be spotted next to Korpardalsvägen, in that case it goes all the way into the center of the town. Almost all the crossings for that bike path have traffic lights to help make the crossings more safe.
This works really really well, as there is no auto traffic to ruin the bicycle pedestrian interaction, and the connectors are short so there are minimal issues with bicycles and pedestrians sharing the same space.
Eugene OR did this with blocking streets off and forcing autos to turn and let bicycles through. Auto traffic becomes one way, which is safer for pedestrians and calmer for bicycles. Yet on a bicycle you can cut miles off the route by not having to wind around in the roads.. on the auto side though, it’s rougher driving cross town through a neighborhood.
Having lived in both models, the cul-de-sac results in small front yards and huge backyards. It tends to isolate neighbors behind walls and fences, resulting in a polite nod each day as we all headed for the car in the driveway.
It’s a bit of a fallacy that cul-de-sacs (CdS) are safer. Because of the lack of external traffic there are fewer eyes to see a robbery in the middle of the night, and the end of a CdS is dangerous for children, many are hit by cars backing out from neighboring driveways.
Until public perception and demand for CdS change it won’t matter, because any rational builder is going to construct when he/she can sell the easiest for the most orofit.
Exactly, developers build on the cheap; that’s why we have surface parking lots instead of structured ones
More importantly (from a safety standpoint), teens have to drive everywhere on highways or relatively high-speed arterial collector roads, as opposed to walking, biking, or taking transit to school, work, and parties.
You are kidding right? All the houses face each other. Neighbors are looking at roughly 4 to 5 other houses and any strange car in the Cul deSac is instantly noticed. Our neighborhood robberies have all been out on the main drag.
Human Transit’s Jarrett Walker will be in Seattle July 29-31, and speaking on the 29th. Details at humantransit.org
You say that the grid is more “walkable” but you also say Griddlers use a lot of transit.
Transit isn’t walking.
And walking isn’t the only exercise. Kids in cul de sacs can be seen biking, running, and playing…safely with minimal automobile traffic.
While cul de sacs are not “carfree” what they do is minimize the number of cars coming throught the street. Only those cars in the cul de sac, enter the cul de sac.
This means the area in front of the house is a play ground.
And walking for adults might mean jogging at night, or riding a bike or doing things that don’t necessarily involve going to a store and spending money.
Another thing you never examine in these walkability studies is the mall. Yes, people drive to the mall, but inside they do quite a bit of walking.
Overall a study that is published under the banner “Back to the City” is not to be trusted, because it must have too many preconceptions.
One thing that journalists should explore though, is the unceasing polemic of “urban” living that seems to be driven mostly by high density real estate developers and people who want the middle class to cede property and become rat moles in overpriced cubby hole condos. The usual criminals are indicted.
I find walking to be more fun if it’s part of my commute, but since I work downtown it works out very well. I only drive to Aurora Village if I start work early (via the first 358 of the day) and walk to the bus stop at all other times. It’s comforting to not have to worry about parking.
No one said that transit is walking. But a better walkshed (a consequence of an orderly street grid) puts a greater number of people within walking distance of a bus stop or transit station, helping reduce the number of SOVs on the roads.
“Overall a study that is published under the banner ‘Back to the City’ is not to be trusted, because it must have too many preconceptions.” This is a logical fallacy called “poisoning the well.”
there’s one other thing: woodinville sucks, as does the east side. that whole area is a big mess of development pushed by the masterbuilders (who owned the King County Council and still do) who push these [expletive] developments. and now there’s no way to fix it. [expletive]
That’s not at all constructive. There are plenty of ways to fix it, and John hints at one.
It’s culs-de-sac, not cul-de-sacs or cul-de-sac’s.
Wrong. That’s a highly formal take on usage. The latter two are perfectly acceptable in common practice. Check any dictionary.
Both are accepted – culs-de-sac maintains the morphological structure from the original French, but most of the time when we borrow words from other languages we treat them like a single morpheme and stick them in English morphological structure. If I had to guess, I’d say that eventually we’ll say cul-de-sacs and no one will say culs-de-sac. Even now, culs-de-sac gets about 304,000 hits on google when cul-de-sacs get about 17 million.
I’m confused. You replied to me, but we agree!
Even if the plural form “cul-de-sacs” is acceptable, there’s no universe in which that apostrophe would be.
“The cul-de-sac’s neighbors got together for a BBQ.” :-)
Even if? Merriam-Webster’s isn’t sufficiently authoritative for you?
As to the possessive, I’d certainly restructure the sentence to avoid it if editing a manuscript for publication, but complaining about it here seems like nitpicking—these folks aren’t professional journalists, they’re unpaid, and yet they manage to put out one of the best transit blogs in the country while going to school, pursuing careers, and raising families. The fact of the matter is that if it is acceptable to treat it a single word for the sake of the plural it is not a stretch to treat it as a single word for the sake of the possessive.
Just call it a Dead End or, better yet… Freedom Street :=
You don’t suppose there was any bias in choosing a Woodinville “neighborhood” that is bordered on two sides by the freeway instead of say all the apartments and condos on the east side of town. Anyway, The northwest corner of the area they chose is a trailer park and I’m pretty sure that it’s actually City of Bothell. The area to the west is a steep bank that’s unbuildable. The large “empty” area to the northeast is wetland. Terrain precluded building a grid in this area unless the developer had taken a Denny Regrade approach to pushing through the roads. But it wouldn’t have made a hill of beans difference to transit because this area is to far from major density and jobs to support all day transit anyway.
As for commuting this whole area is walking distance to the bus stop on the ramp to 522 which gives you great access to the entire system. For non motorized transport in Woodinville you ride a bike, not walk (although from the area they chose walking to the HS is pretty good). It’s an easy bike ride to Bothel P&R or Woodinville P&R or directly to UW/Cascadia. Bikes are many times more efficient than walking and I’d much rather ride in east King County than Ballard. And if you do ride through Ballard you don’t use the back streets with parked cars and uncontrolled intersections.
Expanding on what Bernie said above, the Woodinville location is on a hill, while the Ballard location is on a gentle slope. One could point out that Ballard has better pedestrian connections than the Woodinville neighborhood is because Ballard is flatter. Also, the study chose a suburban location next to the freeway. Maybe if the urban location chosen for the study at I-5 through the U-District, we would see (slighty) different results.
Now, i’m not disputing the idea that the urban grid is better for pedestrians than cul-de-sacs, because clearly the urban grid is better. I just don’t think the Woodinville location is a good choice as a test subject. However, this study does show that freeways break connectivity, as mentioned on this blog numerous times.
I’m on the south slope of QA in Seattle. It’s a very steep slope and we stairs where the roads end because it’s too steep. We also have buses on the few streets that go through. So I think a modified grid pattern can work on any slope where houses can be built.
Bernie, my comment below was meant to respond to yours. I thought I clicked “reply to this comment”, but I guess not… oops! :)
I don’t think your assertion re: biking in Ballard is valid. I live in in between Fremont and Ballard, and when I bike, I specifically try to avoid major arterials, in favor of collectors and/or residential streets. Instead of Stone Way, I take Woodland Park Ave. Instead of the Ave, I take Brooklyn. Et cetera.
In Seattle, the speed limit on residential streets is 25 mph. Roundabouts (and other traffic-calming devices) exist to bring actual speeds down closer to that level. I don’t know about you, but I certainly don’t bike at a sustained pace anywhere near 25mph…
As others have been saying, this is one of the reasons that grids are so nice. With a street hierarchy, everyone is eventually forced onto major arterials, which are never that suitable for non-motorized traffic. With a grid, it’s trivial for different types/speeds of traffic to segregate onto nearby streets.
The grid has advantages for cars too. If one street is congested, you take the next street. People generally choose a street close to their origin/destination, so they aren’t all bunching up on the same street. With cul-de-sacs, there’s only one road in and out of the neighborhood. Which is why there’s worse neighborhood traffic all over the suburbs and exurbs than in Seattle.
None of the routes you mention (except may Woodland, I don’t know that street) are the backroad neighborhood “alleys” with cars parked on both sides and enough room for just one car to squeeze through which is what most of this supposedly connected grid amounts to. Bellevue is roughly 8 block spacing (county grid = 1/2 mile) for through streets. The street layout isn’t the problem; it’s what Bellevue does/doesn’t do with those streets that’s the problem. Kirkland west of 405 is bad but that’s largely because of the terrain. On the bright side Kirkland and Redmond have done a much better job of making streets safe for cycling than Bellevue.
Central Bellevue has superblocks, which may be good for cars but are frustrating for pedestrians. But east of 164th Ave NE or south of I-90, it’s all cul-de-sacs. And residential streets between the superblocks are random and don’t go through, which makes them similar to cul-de-sacs. Like cul-de-sacs they’re easy to get lost in. Unlike cul-de-sacs, at least there are exits on both ends of the street.
Have you tried to walk around DT Bellevue lately. The City has done a great job of providing pedestrian access. Pedestrian paths are much nicer to walk along than through streets (granted bike access is still lacking). There’s no need for a bus route every block so why would through streets on a two block grid be bad for transit. In fact, less intersections which make it better for cars do the same for transit since buses are victims of the same traffic woes as cars.
The city is laid out on a grid, you’ve got a house number, Avenues run north/south, Streets run east/west. Through streets (the ones without no through access signs) are about every 8 blocks. How do you get lost? If you’re just looking for a cut through route well, guess what, that’s why the streets don’t go through. Residential neighborhoods are for the residents, not commuters looking for a faster way home.
Toward Lake Samamish is harder but it’s on a steep bank roads were put in to work around that and to try to make the best use of the lots when sub dividing. Same thing for Sommerset. But again, if you don’t live there, don’t have and business there, why do you care? Just don’t go there and everybody’s happy.
I lived there for twelve years growing up. Yes, downtown Bellevue has through streets in between (NE 2nd, 102nd through Bel Square, and the pedestrian path on NE 6th). Yes, the grid numbering makes it easy to know where a house should be. Yes, buses can negotiate superblocks fine. The problem is mainly for pedestrians and east of 405. It’s not just residents who go into the neighborhoods. People visit other people. People go to the businesses on NE 20th/Northup Way which has skeletal bus service. Here are three real trips I’ve made multiple times:
1) Start at NE 8th/124th or NE 8th/132nd (bus 230/253). Walk north to NE 20th/130th. In the rain. I sometimes go to events at a martial arts school and a user group meeting in an office park.
2) Start at NE 8th/140th (there’s a church there). Walk east to Crossroads, or north to the Safeway on Bel-Red Rd.
3) Start at NE 8th/Northup Way. Walk northwest to NE 20th/148th. There used to be a movie theater across from the Fred Meyer, with late night shows, and no bus to get to them. (And Northup Way had no streetlights then — scary.)
The cul-de-sacs and random streets east of 405 cause problems for both peds and cars, when going to somebody’s house and you’re unfamiliar with the neighborhood. Is it 10th Street or 10th Place? Where does 10th Place start? Hopefully you have a good map with you.
There’s lots more mid-block walking paths to the pedestrian network in DT Bellevue. Anyone complaining about not being able to walk somewhere DT either hasn’t done it or is just a whiner.
The 520 bike trail covers this exact route. It’s a bit strange that there isn’t better bus service though to the NE 20th/130th intersection at least mornings/evenings since Metro uses it as the return to base route. OTOH, there’s not much there (church with 3 acres of parking up the hill, mostly empty office park, abandon Shell station, 7-11 and a lumber store); unless you connected with a bus on 140th. NE 20th is Luxury Auto Row. There’s little there (or on Northup) to generate ridership. It would just be more empty buses driving around the eastside.
That’s way the heck out in single family home neighborhood. It’s an easy 1 mile bike ride to Crossroads (or down hill to East Lake Samm.). If you live off the beaten path then there should be no expectation of front door transit service. Back in the days they were showing Rocky Horror Picture Show there wasn’t much in the way of bus service anywhere on the eastside. 520 at that point ended at 148th and there was a gravel P&R. The idea there should be transit home from a midnight movie on a weekend? That’s a stretch just about anywhere.
The speed limits on many suburban residential subdivision streets are 25 mph as well. However, most cars are parked off-street which leaves a 30-foot wide speedway where vehicles can zoom by at 30-40 mph. When there’s a parent meeting at the nearby school both sides of the street are filled with parked cars, which narrow down the street and greatly calms traffic (likely more so than other devices).
With all this talk of walk-sheds, we seem to be ignoring another huge benefit of grids, which is legibility.
In my experience, one of the biggest obstacles to getting people to walk and/or use transit is that they feel it’s too complicated. They already know how to drive out of their cul-de-sac, and the arterials are arranged on a grid with lots of easy-to-read signs telling you where to turn, so it’s never hard to get somewhere in the car. (I must admit that I find it funny to hear people arguing so fervently against grids, when the arterials that make street hierarchies possible are so perfectly regular.)
In the fused-grid model, there would be lots of extra pedestrian passageways, but using those would require learning where they all lead. For a lot of people, that’s just too much work.
A related problem is that, in my experience, people who live in street-hierarchy-based subdivisions tend to value the feeling of safety more than average. Nothing makes you feel unsafe like walking in an unfamiliar territory where no one else is around. If you get lost on pedestrian-only paths in a subdivision, where the houses all look similar and there are no landmarks or easy directional clues, you’re not going to be eager to repeat the experience.
With a perfect grid (e.g. Midtown Manhattan-style), if you know how to drive somewhere, you already know how to walk there. And it’s almost not possible to get lost, since virtually wherever you are, you can get anywhere with only a single turn.
I’ll stop now, because I’m basically just repeating Jarrett Walker’s arguments (see http://www.humantransit.org/2010/06/on-standard-street-grids.html and http://www.humantransit.org/2010/02/the-power-and-pleasure-of-grids.html). Suffice it to say that, while connected streets are better than cul-de-sacs, I’m not ready to give up a real grid quite yet. :)
Boy you’d have to be a real dolt to get lost walking from your house in suburbs; it’s not like you’re in the deep woods or something although the cliff dwellers might feel that way. If it’s “too much work” to figure out how to get there then that person’s not a candidate for walking anyway. LOTS of people walk and jog on the trails in my neighborhood and very few people want to take the same route everyday so you quickly learn the access routes. The city also puts up signs, often with milage to the 1/10th of a mile.
I don’t think it’s valid to dismiss the “lost” argument so flippantly. Yes, you’d have to be an idiot to not know how to get home, etc. etc. But what if the route from your house to the grocery store takes you through someone else’s subdivision? And what if their subdivision happens to have the curvy streets arranged in such a way that if you don’t know to turn left at the second intersection, you’ll end up walking in a giant circle? And what if it’s at night, so you can’t even see the limited landmarks you might be familiar with?
The fact is, people do get lost. That’s why GPSes sell. And, all things being equal, a more complicated street network means there are more chances to make a wrong turn and fewer chances to recover.
As far as trails go, it’s much less important to know precisely where you are when you’re out on a recreational walk/jog. Detours are part of the fun, as long as you can get home when you’re done. (Most urban/suburban trails that I’ve seen tend to be linear, which means that when you feel tired, you just have to turn around and you’ll get home.) By contrast, if you’re walking to the grocery store, going 2 miles out of the way is not most people’s idea of a good time.
It’s also important to note that people are more open to new experiences when they’re less stressed, and people tend to be less stressed when they aren’t in a rush. In my experience, people tend to be less rushed when they don’t have a destination in mind. I know lots of people who are happy to go on 90-minute strolls through their neighborhood, but who will drive to the grocery store even though it’s only a 15-20 minute walk away.
Of course, people don’t jog or take a stroll carrying bags of groceries and a half rack of beer. Most homes in Bellevue aren’t within a 20 minute walk of a grocery store and it wouldn’t make any difference if all of the streets were connected in a perfect grid. There’s not enough density to support a super market every eight blocks and the old mom & pop corner store model just can’t survive on the 2-3% margins grocery stores work on. OTOH, there are plenty of homes, condos and apartments that are withing walking distance of stores. Loads of people walk from the apartments and condos along 148th Ave NE to the Safeway and Fred Meyer. It’s also clear that most are immigrants to this county and come from a culture where walking is just something you do rather than sit around and find excuses not to. It’s funny though, if you go into the Pro Club you’ll find it full of second and third generation Americans that drive there to use the treadmills, elliptical traniers, etc. Go figure, maybe it’s because they don’t have to worry about getting lost on the treadmill :=
I’m not sure I agree that a “grid” is somehow better than an irregular street pattern. I think the key is connections, regardless of how those connections are dispersed. For example, check out this map:
Venice is quite obviously a great walking city and it does not have an identifiable grid.
I also think that legibility is relative. Yes, when looking at a map, it is easy to understand a grid pattern. But when it comes to actually finding those streets when walking it can be quite difficult because they are all set up the same. A good example of this is the constant confusion between Pike and Pine on Capitol Hill. Myself along with numerous friends have constantly had difficulty remembering which places were on which street. This is the reason why many city streets are numbered, an unfortunate fact which undermines culture, history, and urban identity.
Finally the street hierarchy system is useful in funneling traffic to major streets. If the side streets simply don’t go through, they are sure to remain calm and quiet, certainly a valuable thing in an urban place. You can also focus traffic mitigation measures on the arterials instead of spreading the resources aimlessly.
“Venice is quite obviously a great walking city and it does not have an identifiable grid.”
Have you ever been to Venice? You seem to be describing it as a place that is easily legible without a grid. It is a great city to walk around and let yourself get lost, but is notoriously difficult to navigate.
The graphics are really revealing of how walkability can be so affected and circulation of the community can really be impacted by cul-de-sacs. Really interesting article all-around.
Cul-de-sacs are pretty common anywhere that you see roads put down after about 1960. It’d be prohibitively expensive to tear them out and put a new lay out…
But I wonder if we could afford to/have the right to/could get support to purchase just enough of the land to have cut throughs – make sure there were straight ways available only to bike/ped. It’s be cheaper than a path the whole way through and it would greatly improve walkability.
What it wouldn’t do is create the commercial-near-residential you get in Ballard (three blocks to Cupcake Royale? LETs GO!) but it’d be something and it’d get kids to school faster without hurting the traffic calming on the cul-de-sacs as they exist.
All it takes is a city policy encouraging cut-throughs. In many neighborhoods, the kids already know the ways through, or sympathetic neighbors allow them to cross their property. If a few cut-throughs are successful, more will come. The main problem is where there’s absolutely no room for a cut-through without chopping somebody’s yard significantly. That’s where you wish the cities had planned for cut-throughs in the first place.
It is interesting to note that the planned community which arguably introduced the cul-de-sac to 20th-century America was meticulously designed with pedestrian through-routes and common park areas (the latter spaces were presumably memorable enough to prevent the “getting lost” problem):
Of course, later suburban developers borroed the cul-de-sac concept, did away with the pedestrian through-paths and common areas, and left us with the mess we now enjoy.
Have you ever thought of organizing a protest march against Cul-de-sacs?
The marchers would just end up trapped on a landscaped dead-end street with nowhere to go.
It’s interesting that Wikipedia defines cul-de-sac as any dead-end street. To me, a cul-de-sac is a short dead-end street with an enlarged end like a bulb.
If cul-de-sacs continue to be built, then adding walking/biking paths connecting cul-de-sac neighborhoods should be a requirement for builders and city planners.
Bernie touched on this earlier, but I wanted to talk more about it. In a lot of suburban developments in our wet and hilly Puget Sound region, which has comparatively stronger environmental requirements for development than a good portion of the country, a lot of developers are constrained as to where they can put a road (or even trail) by things like wetlands and steep slopes, which are generally regulated under the Sensitive Areas Ordinance. Also, development regulations generally differ between municipalities, and the line between Bothell and Woodinville goes right through the middle of the area pictured. It is unlikely that the original developments went across those lines. Back when they put down the grid pattern in Seattle, no environmental regulations existed, and I imagine building codes weren’t that existent.
I don’t know the facts about the history of neighborhood development in Seattle. There’s info about downtown, and that one of the three founder’s grid plans won out over the others, but not much info about how the newborn city managed to regulate that the grid pattern be followed. It may just be that the land was all divided into rectangular lots based on portions of the Section-Township-Range by the owners of the land, and since there were no regulations otherwise affecting the development of the parcel, building in a grid made sense. I can’t imagine developers in the early 1900’s were any less greedy than developers now. Developers in the early 1900’s also had absolutely no compunction about altering the land to fit their needs, draining wetlands and leveling hills as were convenient (See Denny Hill and the fact that Greenwood is on top of an old bog).
Suffice to say, I imagine it’s pretty darn hard to get a big hunk of land on which you don’t have to care about environmental or political boundaries these days.
My point being, that 150-some years ago were very different times in terms of the way land was bought and sold (particularly in terms of quantities), and what you could and couldn’t do on a bit of land, so I don’t think you can effectively compare these two areas. I’d be interested to hear more about how communities have strived to be walkable given modern restraints on development. There can’t be much done about environmental constraints, but I do think a lot could be done to overcome some of the political boundaries and doing more large-scale planning that would better connect different developments to each other.
And in defense of cul-de-sacs from a biological perspective, more roads are generally bad for wildlife, which a grid system as pictured generally creates. Cul-de-sacs can often be used to maximize the number of lots without having to bisect a wetland or other biologically important area many times. All the dead end cul-de-sacs empty onto one collector road, which crosses the environmentally sensitive area to the next piece of development (or arterial). The idea is to leave the largest uninterrupted natural area possible. There is more to it, but that is the basic idea.
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