Advocacy & Safety - Speaking of traffic calming...

In another thread, SBHikes wrote regarding John Forester:


The group that hired him is against traffic calming...

To my personal frustration, many cycling advocacy groups and individuals are against traffic calming projects. Many times, it's local cyclists who completely derail traffic calming efforts. The most effective tools in a traffic calming 'toolbox' are unloved by activist cyclists: traffic circles, bulb outs, on-street parking, narrow lanes and so forth. That leaves engineers with almost useless traffic calming measures such as stop signs and speed bumps -- studies show that motorists actually drive faster between these measures!

I personally like traffic calming engineering in neighorhood streets -- I look at streets as a system with multiple users, and anything that adds interest is good for the safety of all street users, even in the United States.

Examples that I'm personally aware of:

Atlanta cyclists killed East Wesley Road traffic calming project (2007)
Silicon Valley Bicycle Coalition advocates removal of Mary Avenue bulb out (2007)
In Longmont, Colorado, cyclists worked with motorists to remove 'dangerous' traffic circles on Mountain View Avenue (2005)


RFM

To my personal frustration, many cycling advocacy groups and individuals are against traffic calming projects. Many times, it's local cyclists who completely derail traffic calming efforts. The most effective tools in a traffic calming 'toolbox' are unloved by activist cyclists: traffic circles, bulb outs, on-street parking, narrow lanes and so forth. That leaves engineers with almost useless traffic calming measures such as stop signs and speed bumps -- studies show that motorists actually drive faster between these measures!
Amen.

The inverse of traffic calming is traffic "uncalming", measures that cause traffic to "speed up", which "bike advocates" often support:


removal of onstreet parking
adding a painted buffer at the edge of the road (a.k.a "bike lanes")
road/lane widening
dedicated turn lanes

I find many traffic calming devices/designs to be cycle unfriendly and while some do slow traffic, they don't neccessarily calm it or cause drivers to be more aware of other road users.

Here is a start at one cities attempt to catalog traffic calming designs and rate them for how they impact a wide range of roadway users:

http://www.tempe.gov/traffic/NTMPDraft_1.22.07.pdf

I very much recommend anyone wanting to discuss traffic calming designs read section 4.

Al

http://www.tempe.gov/traffic/NTMPDraft_1.22.07.pdf

Thanks for pointing to that. I've seen similar documents. The chart at the begining of Section 4 is a good one.

The point is that effective traffic calming often seems to increase bicycle and pedestrian traffic, in the U.S. as well as Europe. Berkeley, California, for example, removed bike lanes when they narrowed Milvia Street, and bicycle traffic DOUBLED. The street became much more cyclist (and pedestrian) friendly because traffic moves closer to bicycle speed. I see the same thing every day on University Avenue in Palo Alto.

The bulb-out in Sunnyvale I mentioned earlier is understandable -- Mary Ave is not part of a comprehensive traffic calming project. The city added a bulb out at one intersection and called it good. The result is that traffic still moves too quickly, but now cyclists have to merge into that fast traffic to get around the choker. Traffic calming is not easy, but when it's done right it works very well.

One solution I've seen is a median that's like an inverse bulb-out -- instead of forcing the cyclists to merge into the car lane, the median forces the motorists to merge toward the right of the road. Motorists at this location must wait for cyclists in the bike lane.

RFM

fritz, is your avatar a photo of you waiting on a bike in traffic next to a clear bike lane? seems you might want to get out of your 'bicycle driving' paradigm and use a bike like it is a bicycle....

The most effective tools in a traffic calming 'toolbox' are unloved by activist cyclists: traffic circles

The traffic circle they built on my commute route recently isn't very well loved by myself or any other cyclist - the greenery they planted actually reduced visibility of the other traffic as compared to the old intersection, and the drivers blow through the thing with no concept of ROW. 4 cyclists were hit in the first 3 months as compared to only one in the entire previous year. I like traffic circles, but introducing poorly designed circles in an area where the drivers are not used to them, combined with stupid shrubery tricks, can be a recipe for disaster.

Bike advocates in my area are not against traffic calming. We believe in making our streets safer for all users. It's the car advocates in my area that are against traffic calming and they use "dangerousness" to bicycles as a ruse to get people to be sympathetic to their cause, especially when it comes to mini traffic circles and bulbouts. We cyclists counter that those devices are supposed to reduce your speed to something closer to bicycle speed so that there should be no safety issues for cyclists. The only danger comes from those who insist on going 40mph through the calming devices.

fritz, is your avatar a photo of you waiting on a bike in traffic next to a clear bike lane?

Nope, no bike lanes on that street (U.S. 287 through Longmont, Colorado). Its taken from a left-turn lane. Full size is below.

Back on topic: This is a U.S. Highway and arterial through a commercial part of the city, so lots of traffic calming is probably not appropriate for this street. Unfortunately, there also isn't much in the way of good north-south bike routes in this city. I only rode on Main Street if my destination was actually on Main Street.

FWIW, I suggested bike lanes for this street (http://www.masoner.net/photos/bike/bikeseye/Commute-04-SunsetAvenue.jpg) and the city considered restriping for three lanes (one in each direction plus middle turning lane) after they repaved it.


http://www.masoner.net/photos/bike/bikeseye/Commute-06-MainAt3rdLeftTurn.jpg

Bike advocates in my area are not against traffic calming.

I'm very glad to know that. I hope to see more of this kind of thinking as we move forward.


(regarding traffic circles) 4 cyclists were hit in the first 3 months

Was this a traffic circle, or a roundabout? Roundabouts are indeed dangerous for cyclists, but these are used to move car traffic through an intersection more quickly. Also, I can imagine that poorly designed traffic circles can be more dangerous.

The only cycling advocacy group that I know of that supports the use of traffic circles is the San Francisco Bicycle Coalition.

RFM

Amen.

The inverse of traffic calming is traffic "uncalming", measures that cause traffic to "speed up", which "bike advocates" often support:


removal of onstreet parking
adding a painted buffer at the edge of the road (a.k.a "bike lanes")
road/lane widening
dedicated turn lanes



I definitely favour onstreet parking - there's many a road that could benefit from that. However, I'm referring to parallel onstreet parking - diagonal onstreet parking is a cycling nightmare! I used to ride past a few blocks of on-street diagonal parking to work (in the dark too).

Why would cyclists (or pedestrians) advocate for dedicated turn lanes? Anything that allows/encourages cars to turn at high speeds is incompatible with cyclist/pedestrian safety, with the attendant lane changing or traffic crossing that is required.

One highly effective traffic calming measure that works in my neighbourhood in toronto are traffic humps (i.e. speed bumps that allow cars with a good suspension to take at speeds of 20mph [30km/h] or less). The only disadvantage for cyclists is there is an increased chance of the cyclist rear-ending a car that freaks out suddenly when they encounter a speed bump (that'll teach me to draft cars!).

I definitely favour onstreet parking - there's many a road that could benefit from that. However, I'm referring to parallel onstreet parking - diagonal onstreet parking is a cycling nightmare! I used to ride past a few blocks of on-street diagonal parking to work (in the dark too).
I was speaking of parallel onstreet parking. Diagonal parking can be a problem for cyclists, but it's easy to deal with - just move further left. Also, back-in diagonal parking is an interesting alternative.


Why would cyclists (or pedestrians) advocate for dedicated turn lanes?
It allows for the beloved bike lane to the left of the right turn only lane, for one. It also provides a refuge for left-turning cyclists who are uncomfortable stopping in a left-or-straight lane.


Anything that allows/encourages cars to turn at high speeds is incompatible with cyclist/pedestrian safety, with the attendant lane changing or traffic crossing that is required.
Logic and reason rarely form the basis for "bike advocacy".

The only disadvantage for cyclists is there is an increased chance of the cyclist rear-ending a car that freaks out suddenly when they encounter a speed bump (that'll teach me to draft cars!).
They do get annoying to go over on bicycle every 100yrds. They don't slow one down, they don't cause any impact, but the cumulative efffect of going over a sequence of 8-10 of them is annoying, especially on a hot summer day going home.

The other annoyance is that they slow cars down to 15-20mph, who then speed up to 30-35 between them, often resulting in the car traveling at a near or slightly slower average speed than me on bicycle. So like you point out you catch the car at the humps, use brake to slow down (overtaking will just result in being overtaken again after bump) repeat, repeat.

Al

What I like best is streets where they only allow you to exit at one end and enter/exit at the other, yet are two way as no sign of a one way. Of course bikes have a special curb to enter on.

Or streets with barriers to stop short cuts.

It allows for the beloved bike lane to the left of the right turn only lane, for one. It also provides a refuge for left-turning cyclists who are uncomfortable stopping in a left-or-straight lane.

Around here, right turn lanes are seen by cyclists as simply part of the shoulder to use to travel down arterial roads without getting in the way of motorists. I've been yelled out by a cyclist (driving his car, but I know he's a cyclist because I've rode with him) for not using the turning lane to go straight, putting myself in the middle of a busy road (his words paraphrased). I guess the turn lanes are seen as a win-win for cyclists and motorists. I personally see the discontinuous shoulder as the big nuisance though. I'd rather it just be removed (I could go either way on the right turn lanes themselves) which, as I've seen on a perpendicular street setup this way, makes for a much better cycling experience.

Nothing wrong with removing parking. It makes it easier for everyone to see.

Nothing wrong with removing parking. It makes it easier for everyone to see.

And thus to drive faster, and allows for that wonderful process of driving around for 15 minutes to try and find a parking spot.

Under certain conditions - particularly when there is a lot of fast straight traffic, and no right turning traffic, and the outside lane across the intersection is wide enough to be shared - I will go straight from the right turn lane. I'd do the same if driving a very slow moving motoroized vehicle, like a tractor.

But I encounter those "certain conditions" fairly rarely... maybe once a week.

Streetsblog posted a story today about "second generation" traffic calming at an intersection in New York (http://www.streetsblog.org/2007/02/12/the-seed-of-a-revolution-in-red-hook/). A "mental speed block" -- a sculpture in the middle of the road -- was erected in Brooklyn. The intent of this kind of traffic calming is to create "intrigue and uncertainty" along the roadway.


"The reason great intersections work is because of the creation of a pedestrian realm where the cars know this. When streets become unsafe, it is almost always when the pedestrian realm does not exist."

In the name of mobility, transportation planners have forgotten to create and support destinations, and have instead often degraded existing destinations along the way. Mobility may be increasing, but we are accomplishing less and less while moving around more and more.

As far as East Wesley Rd in Atlanta goes, it appears you're incorrect. This from the local neighborhood newsletter:

<begining>

From: GH Town Crier
Sent: Feb 10, 2007 5:49 PM

Subject: East Wesley - latest development

Greetings from the Garden Hills Town Crier

On Friday afternoon, Commissioner of Public Works David Scott informed Councilman Howard Shook that the City has decided that the East Wesley project would be completed as originally designed (with bulbouts and no particular provision for cyclists) and approved. The Commissioner said that we should expect to see full-scale work resume on Monday morning.

An alternate bicycle route through Garden Hills (not yet completely agreed-upon by staff) would be shown on a revised official Atlanta Bicycle Route plan. The said newly-designated route would not legally require and therefore does not contemplate special on-site signage, striping, or parking prohibitions.

<end>

Personally, I think traffic calming is a bass ackwards way of dealing with the problem. Attempts at engineering the roads to psychologically persuade people to behave only work for a short while.

What we need is driver education. It's a proven fact that driver education drastically reduces the number of collisions. It's a long term solution, and it is the only solution that works everywhere, all the time.

Az

driving a tractor, or riding your bike, helmet? i figured you as a once a week bike commuter.


sorry, this is about traffic calming. there are ways to mix bicycling and traffic calming measures effectively. there are also ways to stripe roads to the benefit for all public space users.

using a road diet to rework existing 4 lane roads into pedestrian, traffic calmed 2 lanes+center turn lane+bike laned roads can have positive effects on public rights of way. road diets can increase ADT, increase pedestrian safety, increase bicyclists visibility, AND calm streets.

Under certain conditions - particularly when there is a lot of fast straight traffic, and no right turning traffic, and the outside lane across the intersection is wide enough to be shared - I will go straight from the right turn lane. I'd do the same if driving a very slow moving motoroized vehicle, like a tractor.

But I encounter those "certain conditions" fairly rarely... maybe once a week.

How would you handle a series of right turn lanes (where the other side of the intersection begins as a merge lane)? What if these intersections saw relatively frequent merging traffic (turning right onto roadway to go the same direction as you) but not much right turn exitting traffic?

you know the anwser to that, joey!

you know the anwser to that, joey!

Hey, I'm just curious. I might learn something new. You should try it sometime ;)

from the great armchair cyclist? naw, he's a bit timid in traffic.

How would you handle a series of right turn lanes (where the other side of the intersection begins as a merge lane)? What if these intersections saw relatively frequent merging traffic (turning right onto roadway to go the same direction as you) but not much right turn exitting traffic?
The default is to eschew the right turn lane for going straight. I would only do so in the exceptional case, where not only was there no right turning traffic from my direction, but also a lot of straight traffic, and the sight lines are good enough to rule out your concern - right turning traffic coming from the right.

The default is to eschew the right turn lane for going straight. I would only do so in the exceptional case, where not only was there no right turning traffic from my direction, but also a lot of straight traffic, and the sight lines are good enough to rule out your concern - right turning traffic coming from the right.

Thanks for the response. I probably should have clarified that the road I have in mind is two lanes each direction if that makes a difference to you.

Any input Bek? My current practice is similar to HH's which can be, at times, unpopular. How do you deal with the situation of fast straight traffic which you've been riding to the right of but then encounter a turn lane? Screaming for a road diet is not an option :)

from the great armchair cyclist? naw, he's a bit timid in traffic.
The great armchair tractorist is more like it.

Personally I have no problem with traffic calming. It bothers me not at all. Most people drive way too fast. I don't. So it doesn't bother me.

What I do object to is when people who are against traffic calming try to appeal to people's fears about riding their bikes. They like to claim that the traffic calming devices force vulnerable cyclists into the paths of drivers and force drivers to have to swerve to avoid killing them.

This, of course, is folly. If people would just slow down, there would be no swerving needed.

I'm sure that HH opposes traffic calming because he's linked to the American Dream Coalition and those people are paid to come and speak against anything that stands in the way of total automobile domination of the roads.

The traffic circle they built on my commute route recently isn't very well loved by myself or any other cyclist - the greenery they planted actually reduced visibility of the other traffic as compared to the old intersection, and the drivers blow through the thing with no concept of ROW. 4 cyclists were hit in the first 3 months as compared to only one in the entire previous year. I like traffic circles, but introducing poorly designed circles in an area where the drivers are not used to them, combined with stupid shrubery tricks, can be a recipe for disaster.
I can see the potential for that happening, Chip. I'm grateful ours are well-planned. When I was still driving a car, they sure had their intended effect on me - I slowed the heck down! As a cyclist, I don't see visibility decreased in any way, but obviously your experience shows that isn't always the way. Hey - any chance you could get a pic of yours?

I took this photo of a traffic circle in Boulder, Colorado. I think you'll like it.

http://farm1.static.flickr.com/30/59548945_3f650606e0.jpg (http://www.flickr.com/photos/bike/59548945/)

now, there's some traffic calming that works for bikes. nice one, richard.

i believe traffic calming can be bicyclist friendly. And restriping roads with road diets can have the effect of calming streets, while improving traffic ADT, increase pedestrian safety ,increase visibility of cyclists AND provide traffic calming.

it all depends on how the lines are drawn, where the changes are made.

(joejack, i know what i do. This thread has nothing to do with dat chestbeat. who cares about your unwavering adoration for HH's lane position?)

What I do object to is when people who are against traffic calming try to appeal to people's fears about riding their bikes. They like to claim that the traffic calming devices force vulnerable cyclists into the paths of drivers and force drivers to have to swerve to avoid killing them.

This, of course, is folly.

I agree. But many real cycling advocacy groups are against many street calming projects. These are not motorists groups in disguise -- these are genuine advocacy groups, many with a strong anti-car bias. The people in these groups may agree in principle with the purpose of road diets, but when the rubber meets the road they often don't like the results.

Conversely, I've also seen groups that start out against traffic calming measure who change their minds after discussion on the issue. As several people in this discussion have noted, a major problem is traffic calming engineering 'done wrong,' so to speak.

RFM

(joejack, i know what i do. This thread has nothing to do with dat chestbeat. who cares about your unwavering adoration for HH's lane position?)

Do you ever answer a question directly? The reason I asked both you and HH is that I was a little surprised to hear that HH would use a turn lane to go straight (hence why I asked for clarification). I'm shocked that you haven't used this oppurtunity to blast him for not following the rule book. I'd also honestly like your opinion on the subject but I realize it's a stretch since you never answer any direct questions. If you don't feel like responding, just say so.

They recently put traffic circles on my neighborhood streets. They placed them at intersections. The City addressed the visability issue by only allowing certain types of plants to be planted which do not restrict visability. They seem to have stopped the drive 60 mph through the neighborhood people. The people who drive fast between circles probably were the ones that drove 60 before so at least it slowed them down some. My only beef with them is that at least half the drivers that take lefts don't go around them.

We also have on street parking. In the three years I've lived here, I've seen several parked cars sideswiped/hit by inattentive drivers.

Traffic calming is also you and me driving at no more than the speed limit on these streets.

Part of my ride home calms a few blocks of residential streets.

My drive home yesterday from the bike shop, took the back way during 5:30 rush hour - all 25mph streets, I kept it at 25mph, quickly cars built up behind me, a long string.

The issue here is arterials are full, motorists choose the backways and push their speed 35-40mph. Its a different mentality - the need to get fast and the need to be minimally delayed so as to do better than if they had choosen the main route.

Having other slow moving vehicles using these routes will make them much less desireable for the 'cutters'

Al

and what if you're on your bike doing the same, al? do you block the traffic and get honked at, or let the drivers go 35 or 40 on those side streets.

I rather like the picture of Boulder's traffic calming. very nice.

Traffic calming is also you and me driving at no more than the speed limit on these streets.

Part of my ride home calms a few blocks of residential streets.

My drive home yesterday from the bike shop, took the back way during 5:30 rush hour - all 25mph streets, I kept it at 25mph, quickly cars built up behind me, a long string.

The issue here is arterials are full, motorists choose the backways and push their speed 35-40mph. Its a different mentality - the need to get fast and the need to be minimally delayed so as to do better than if they had choosen the main route.

Having other slow moving vehicles using these routes will make them much less desireable for the 'cutters'

Al

D'oh! that was you? man, that was annoying. we all hated you. ;)

and what if you're on your bike doing the same, al? do you block the traffic and get honked at, or let the drivers go 35 or 40 on those side streets.

I rather like the picture of Boulder's traffic calming. very nice.
I do the exact same car and bike on these 25mph streets - hence both the bicycle and car examples.

I was aggressively passed twice and honked at once during my drive home on a 4mi stretch of 25mph street from the LBS yesterday.

There is no need on a bike to block traffic on these streets - except approaching intersections, or passing the occasional parked cars. I manage the aggresive drivers fine, not by any unusual aggressiveness on my part, but my just riding along in a lane position needed for my desitination, and give the occasional car that approaches from rear the slow down signal.

Al

D'oh! that was you? man, that was annoying. we all hated you. ;)
I was going south on College (25mph posted) and then east on Alemeda (also 25mph posted)
Driving my car at 25mph I ended up with a line of vehicles 9 long behind me at the McClintock crossing.
As I said above it resulted din one truck passing the line of me and two other cars behind us, honking as they passed me. Another pass later on - which resulted in me catching up to them at every speed hump, I kept a constant 25mph, they went 35mph between humps and slowed to 15 over them.

Al

and what if you're on your bike doing the same, al?

In other words, a one man Critical Mass.

Increasing cycling and pedestrian presence on a street also has a traffic calming effect. Make the street seem safer for cyclists and pedestrians, you'll increase the number of these other users, resulting in more traffic calming for that street.

Guerrilla Street Calming

In my previous neighborhood in Colorado, the street was your typical 40 foot right of way in a new subdivision. Nominally 25 mph speed limit, but the wide street is engineered for 40 mph. The road provided access to the middle school at the end of our street, so we had lots of traffic in the mornings and afternoon.

We put a temporary barrier in the middle of the block -- not a complete barricade but something in the middle that drivers had to manuever around, and we also moved this barrier around. We also purposely left toys in the the middle of the street. Stuff like that works really really well. People learn about permanent structures and adjust their driving so that they don't get slowed as much, but random stuff like balls, scooters, bikes and portable hockey goals are things the drivers have to watch for in that neighborhood.

RFM

On streets designed for high throughput longer distance travel (i.e. arterials) I cooperate greatly with other drivers as nearly all of them are permitted and able to go much faster than me. This means moving over when safe to allow faster traffic to pass.

My more 'political' riding comes on 25mph streets - especially those in my neighborhood. Of course I'll cooperate with considerate drivers, even those wanting to go over limit, or get ahead of me with care even if intersection is not so far off. But those who abuse these residential streets and treat them as shortcuts, made only shorter by racing thru - I get a bit agressive with them - giving slow signal to driver with engine roaring up behind me obviously gong 10-15mph over limit, etc. I do the same in my SUV. If more folks, including residents, of these hoods that want traffic calming drove more calmly, then fewer cutters would find benefit in using residential streets.

Al

richard, that guerrila street calming sounds similar to how the dutch institutionalized woonerfs and the extreme traffic calming these provide.
the Dutch in a city NOT amerdam literally and physically reclaimed the streets over 40 years ago with a guerrila tactics. long since institionalized in the national legislature, what's it called?


toys in the street, good one. isn't that the way most drivers see bicyclists? ;)

I rather like the picture of Boulder's traffic calming. very nice.
I don't - with the bike lane in a door zone too.
The cyclist should already be in primarly lane to go thru constriction long before the bike lane stripe ends. Seems the stripe ended and the sign are much too late.

Al

Al, i'm real happy for your criticisms, but i bet that works remarkably well. richard?


Al, just get off your high horse and realize if you rode there, you'd take advantage of any facility you found appropriate, and leave one you didn't. NOT ALL REDESIGNS of public roads are %100 perfect, nor do all attempts at traffic calming advantage all users.

If that intersection becomes a problen, redesign will be implemented. if it works for the populace, it will not.

that street likely works better than your poorly designed road redesigns in AZ, as there is free traffic mixing according to the cyclists' verve. or swerve, depending on how you look at it.

are you just an anti facilities chestbeater, Al? on the auto-centric bandwagon that serves to limit greater cycling in your community? why predicate your demands on what likely encourages even greater bicycle use in Boulder?

I'm none of that Bek and on no high horse either.

I'm not against the design from Boulder, sure it slows traffic and sure it integrates cyclist, but the implementation could be better. Like that big sign further back from the merge. Sure it works well as is, but I'd bet most if not all cyclist leave that BL before it ends.

I like to explore and learn about the best cyclist facilities to meet a range of cyclist needs and for the type of road layout where I live (high speed arterials on 1mi grid w/frequent intersections bounding a maze of residential streets) that WOLs are the best facility. I'm also fine with the aesthetic improvements being made to canal routes here, of little use for me, but make for good interconnect for recreational and unique cases of transportational cycling.

If intersections (of all kinds) were far less frequent (i.e. every 1mi or so) I'd be fine with BL striping on faster and well maintained roads as long as the stripe ended 200' before any intersection where there is not a RTOL.

Al

Was this a traffic circle, or a roundabout? Roundabouts are indeed dangerous for cyclists, but these are used to move car traffic through an intersection more quickly. Also, I can imagine that poorly designed traffic circles can be more dangerous.

Sorry for my ignorance, but what is the difference between a traffic circle and a roundabout?

Sorry for my ignorance, but what is the difference between a traffic circle and a roundabout?
http://www.azdot.gov/Roundabouts_Common/images/ctoon_cowboy.gif
http://www.azdot.gov/CCPartnerships/Roundabouts/faq.asp

"What is the difference between a Traffic Circle and a Modern Roundabout?
Modern Roundabouts are different than traffic circles in the following ways
Traffic circles can involve stop signs or stop signals
Traffic circles can be very large or very small
Traffic circles can operate at higher speeds and often require motorists to move from one lane to another
Some traffic circles still exist in the USA, however safety and operational problems caused many of them to fall out of favor in the 1950s and 60s.

Modern Roundabouts are not Traffic Circles
Modern Roundabouts follow a yield at entry rule, which requires approaching vehicles to wait for a gap in the circulating traffic before entering the Roundabout
Modern Roundabouts involve low speeds for traffic entering and driving through the Roundabout
Modern Roundabouts use deflection to slow entering traffic and enhance safety
Vehicles in the Modern Roundabout have the right of way "

Hey, thanks noisebeam.

Some of you guys know each other too well ...

Another thing that is unclear, is the cycling advocacy groups' disinclination for traffic calming. As a city resident, it is easy to convince me that people drive too fast. My wife was run over by a van at the intersection by our apartment and we drive less than the average family. But it seems like something advantageous for cycling in particularly dense areas.

Is it the case that despite the name "traffic calming" such measures make drivers more aggressive like the situation described the previous post that described traffic on streets with numerous speed bumps?

There is a residential area in a DC suburb with small roundabouts. For those familiar with the area, it is in Arlington between Wilson Blvd and Route 50. Anyway, my understanding is that people used to cut through the neighborhoods often. At some point, several connecting roads were blocked and speed bumps and small roundabouts were installed. It appears to me, the occasional visitor, to work well despite the population boom in the last ten years. Would this be an example of traffic calming?

http://www.azdot.gov/Roundabouts_Common/images/ctoon_cowboy.gif
http://www.azdot.gov/CCPartnerships/Roundabouts/faq.asp

"What is the difference between a Traffic Circle and a Modern Roundabout?

I wasn't aware of this nomenclature of "Modern Roundabouts." I learned something new. I was using 'roundabout' for the big, high speed traffic circles, and 'traffic circle' for the small "modern roundabout" designed to deflect and slow traffic.

Regarding invisiblehand's comment: Speed bumps are considered almost obsolete. Nobody likes them: they damage cars and they create a lot of noise. Speed bumps result in increased speeds between the bumps. Same with stop signs that are placed for 'traffic calming' purposes instead of to determine right-of-way.

RFM

There is a residential area in a DC suburb with small roundabouts. For those familiar with the area, it is in Arlington between Wilson Blvd and Route 50. Anyway, my understanding is that people used to cut through the neighborhoods often. At some point, several connecting roads were blocked and speed bumps and small roundabouts were installed. It appears to me, the occasional visitor, to work well despite the population boom in the last ten years. Would this be an example of traffic calming?
That's the kind of traffic calming I'm familiar with.

they've used and are increasing use of 'planter circles' in the middle of intersections to add traffic calming in residential areas in seattle with effectiveness. and they work!

Anyone else in here familiar with the citizen guerilla work in Holland in the town of Delft and the subsequent nationwide implementation of traffic calming in that country known as 'woonerfs' very interesting story.

In the mid 70's, after the third child had been run over in a residential neighborhood in Delft and the authorities refused to take action, citizens armed with picks and shovels literally tore up a road overnight and put in their version of traffic calming.

when the bulldozers arrived with police in tow, the citizens held their ground. this led to 'woonerfs'- living yards- being given legal basis for implementation in the Netherlands in 1976 and changes in traffic rules in 1978.

a far cry from autocentric views held in the US and propogated by a true anti-cyclist, john forester, The underlying and basic principle of a woonerf is that a street is a valuable public space and should be shared by all users.

credit due "the End of the Road; Wolfgang Zuckerman, lutterworth press, 1991