Advocacy & Safety - Choker vs Speed Table

As congestion increases motorists look for alternative routes which often are our cycling routes. But in order for these routes to be a viable shortcut for motorists there is a need to exceed the speed limit which causes issues and concerns.

In order to address these concerns community's have been installing chokers which has alarmed a local cycling community as most feel that chokers make roads less bike friendly, additionally chokers are one of the lest effective measure to reduce motorists speed.
http://www.walkoaklandbikeoakland.org/downloads/Choker.jpg
Effectiveness: http://www.trafficcalming.org/effectiveness.html

Speed tables (long flat raised surface) on the other hand are effective at keeping speed near the desired limit without any significant discomfort to law abiding motorists or cyclists.
http://www.completestreets.org/images/PortlandHump.jpg

So I am curious how you feel.

[Edit: The last line of the poll s/b I like Chokers because they force cyclists to be apart of the traffic flow

They don't slow the fast drivers down, only the cautious ones.

wouldn't speed tables, especially ones made of rubber, be damaged by plows in the winter?

wouldn't speed tables, especially ones made of rubber, be damaged by plows in the winter?
There are ways of dealing with this but I can't speak that informatively on this as we don't get much snow locally.

"I like Chokers because they force cyclists to be a part of the traffic flow."
Italics mine because I assume this is the intended meaning. It doesn't make sense that chokers would force cyclists apart from other traffic. Unless the cyclist is expected to ride on the sidewalk.

Chokers integrate bicycle and motorized traffic. On a route commonly used by bicycles, chokers and bikes in combination would (do) reduce the speed of motorized traffic. Most motorists understand this and may choose to not use that route as a result, as they desire.

I have no experience with speed tables. But it looks like there should be a stencil of a bicycle right in the middle of the one pictured in the OP.


Speed tables (long flat raised surface) on the other hand are effective at keeping speed near the desired limit without any significant discomfort to law abiding motorists or cyclists.
For law abiding, competent motorists and cyclists; chokers should likewise cause no significant discomfort.

Speed tables are really annoying to residents in the area because of noise, with cars slowing for the speed tables then gunning their engines in between. Also, some cars and trucks, and trailers, will alwys rattle or clunk as they go over the humps. A friend lives on a street with speed tables and it's awful. In a couple of other cases the residents rallied to get them removed.

Chokers, OTOH, seem to encourage a more gradual slowing and accelerating. I'm not endorsing those either, but pointing out the problems with speed tables and speed humps.

I wish I could edit the poll, still trying to wake up I guess. So yes it should be A PART not apart.

And please do not confuse speed tables with speed humps, humps are noisy, speed tables are relatively quite quiet. (Edit: I'm having a day.)

I have thought of this. One road on my commuting route is used for a shortcut. The residents were unlucky enough that they built a wide street through their neighborhood. If traffic was driven back onto the main drag where it belongs, I wouldn't have any problem with chokers. I dislike them in general. Not sure about speed tables, I'd have to ride on one.

I did find out that bike lanes don't work to slow traffic, in fact they probably speed things up. Our town took out on-street parking and put in bike lanes. The road has very few houses, it has big fraternity buildings. The speed limit is 25, most traffic goes 35-50. They have warning bumps for the stop sign to make noise.

The most effective traffic calming I've ever seen is periodic enforcement of the speed limit. There is a road near my parents' house that goes from 40mph down to 30mph as it enters a residential area. Everyone goes under 35mph because every so often there'll be a cop car parked in a driveway hidden by on-street parking ready to ticket anyone above the 5mph tolerance.

Some of the roads I commute to work on connect several neighborhoods to more major roads. As such, they are often used as bypasses for the major roads. The speed limit on some is only 25mph yet traffic mostly moves above 40mph. Several stop signs, speed bumps, and even a choke point are present but they do nothing to significantly slow down traffic. I've seen one police car with a radar gun on those roads in the 5.5 years I've been using them. Oddly enough, I've had a few of the locals flip out at me on my bike for going 20mph on those roads (the usual slow cyclist sentiment).

Chokers and cutouts, like traffic circles, are insanity.
As someone who spent a lot of time and money in PA fighting irresponsible
development, I found "Traffic Calming" such as this, is used primarily to sell
huge developments to people where the increase in traffic of that area is a concern
to the citizens going to be assaulted with it. "Consultants"(?) have found this stuff
very easy to sell at zoning meetings, etc.

What about Chokers that 'float' out in the street, but leave the bike lanes undisturbed? (bike lane undercuts the choker)
Seen at least one like this, looks pretty good to me.


WTF is a speed table and how is that supposed to work?


Roundabouts are great fun; they help you to understand british humor.

Simply posting a sign reading "Speed limit enforced by concealed camera" (and actually having a concealed camera every now and again) would do wonders.

This might be held a violation of due process in some states, however.

What about Chokers that 'float' out in the street, but leave the bike lanes undisturbed? (bike lane undercuts the choker)
Seen at least one like this, looks pretty good to me.

You mean an island between the traffic lane and the curb?

It will tend to cause a "surprise appearance" of a cyclist for cross traffic and they will fill up with debris. (More expensive for the municipality to keep clear too.)

Dallas has a number of streets with speed humps, and they work well for cyclists. A surprise problem with them is that warning signs get swiped by nearby college students. Apparently it is quite the status symbol to have "speed humps ahead" posted above your bed. :rolleyes:

Wouldn't municipalities be exposing themselves to liability for causing a hazardous nuisance with chokers?

What about Chokers that 'float' out in the street, but leave the bike lanes undisturbed? (bike lane undercuts the choker)
Seen at least one like this, looks pretty good to me.


We have one of these on my street. It does collect debris, but is usually passable when there is no snow or ice.

I'm all for speed humps. Doofi drivers who haven't learned to drive the speed limit gas/brake like crazy - leaving cyclists free rein to smoke them. This way the aggressive are punished by spending more money on gas, plus the occasional lost oilpan.

However a few motorists have determined that if you just drive the limit, you can drive over the humps and save gas at the same time. At least they're not speeding :P

Measures such as this are a real pain for everyone...

As a cyclist, I've seen this stuff implemented in Oxford, UK and here in the USA. Regarding "Chokers" there is nothing worse than an unpredictable roadway edge that squeezes bikes and car together. I've even seen designs that force opposite directions to meet head-on.

As for speed humps... I see good, bad and ugly. Some are unrideable on a bike - I once crashed as a result of a bump, cycling well below the speed limit... and they punish the users of small cars more than those in large, less efficient vehicles. If the speed limit on a road is, say 30mph then why put speed humps that invariably slow traffic beneath that limit at intervals? Change the limit and do something sensible about enforcement if cars are travelling too fast.

OK, that's my 2p :)

Ed

WTF is a speed table and how is that supposed to work?
This may be of interest: http://en.wikipedia.org/wiki/Speed_table
But basically at designed speed a car "rests" on top before hitting the descent, faster and the car goes up and comes down hard missing the intermediate rest area. I witnessed a Jeep thinking he did not have to slow down for a speed table (doing ~35mph for a 25mph sped table) and he lost some stuff out of the open back area.



Roundabouts are great fun; they help you to understand british humor.

:roflmao2: I am soo stealing that quote.

The most effective traffic calming I've ever seen is periodic enforcement of the speed limit. ...

The problem in California, and perhaps several other states, is that the fastest 1/6 of all motorists determine the enforceable speed limits.

I haven't decided whether to vote #1 or #2, but in general I think I'm leaning away from supporting them. This is the first I've heard of them so I don't want to make a snap decision.

I don't know how far apart they are from each other, but it seems to me that there are basically two ways for cyclists to handle them. Their distance may determine whether the first or second is chosen by more cyclists.

First, unless they are very close together, most cyclists will probably try to stick to the right between the chokers, so they will have to merge back out into traffic to get through them, which there might not be good opportunity to do if a line of cars is passing at the time. A car might intentionally try to beat them to the choker, or just unintentionally underestimate the cyclist's speed.

Or, unless they are very far apart, the more educated and assertive cyclist may decide to just ride a straight line between chokers such that they don't have to change their lateral position when they get there, but motorists may not understand this reasoning and get annoyed that the cyclist is so far out into the lane between chokers.

I don't see either response as a good option for the cyclist. So, definitely #2, and maybe #1.

Wouldn't municipalities be exposing themselves to liability for causing a hazardous nuisance with chokers?

Chokers are part of FHWA accepted traffic calming road treatments http://www.fhwa.dot.gov/environment/sidewalk2/sidewalks209.htm :notamused:
But interestingly enough not part of the MUTCD

However, there are currently no plans to address humps, chokers, and other common traffic calming measures as part of the rewrite. Until the MUTCD is updated to include traffic calming measures, engineering judgment must prevail.
http://www.ite.org/traffic/tcsop/Chapter4c.pdf

I haven't decided whether to vote #1 or #2, but in general I think I'm leaning away from supporting them. This is the first I've heard of them so I don't want to make a snap decision.

I don't know how far apart they are from each other, but it seems to me that there are basically two ways for cyclists to handle them. Their distance may determine whether the first or second is chosen by more cyclists.

First, unless they are very close together, most cyclists will probably try to stick to the right between the chokers, so they will have to merge back out into traffic to get through them, which there might not be good opportunity to do if a line of cars is passing at the time. A car might intentionally try to beat them to the choker, or just unintentionally underestimate the cyclist's speed.

Or, unless they are very far apart, the more educated and assertive cyclist may decide to just ride a straight line between chokers such that they don't have to change their lateral position when they get there, but motorists may not understand this reasoning and get annoyed that the cyclist is so far out into the lane between chokers.

I don't see either response as a good option for the cyclist. So, definitely #2, and maybe #1.

The idea of supporting a design that either encourages cyclists or gives drivers the expectation that cyclists must play jack-in-the-box with traffic I find hard to stand behind.

As far as frequency of placement some cases it's just one you have to deal with in others the spacing is just far enough apart that drivers get really annoyed if you don't pull over and if you do you generally have to slow or stop for the next one in order to safely merge back into traffic (not enough space for a motorist to completely pass a cyclists.)

The problem in California, and perhaps several other states, is that the fastest 1/6 of all motorists determine the enforceable speed limits.

I highly doubt this is the case for all roads including neighborhood roads. Either way, while the speed limit is set at a certain point, it can be enforced at that point. The speed limit isn't ever changing based on increasingly higher speeds of traffic.

I don't know how to vote -

I suspect chokers work effectively only on the most traffic-calmed streets (European woonerfs or Tempo zones), or NA bike boulevards, or are part of what helps make streets that way.

Streets with EXTREME chokers work to calm traffic, IE no thru traffic at choke points.

Residential center planters, the mini traffic circle kind, affect traffic calming but seem to add to bike/car conflicts when both approach simultaneously.

chokers that incorporate bus stops as part of the cutouts can work allright for bike traffic along bike laned streets, but chokers lose effectiveness on any street approaching a neighborhood connector or arterial route- unless municipalities are looking to genuinely reduce traffic speeds and volumes....not dress up a high ADT roadway.

I'm all for speed tables versus chokers. Why not both?

Speed humps are annoying.
Chokers here don't look anything like that, so I don't want them.
http://img129.imageshack.us/img129/4070/img8391.jpg

This is a choker notice the middle median?

They also have what you have pictured above but there is a bike cut out for a bike lane/shoulder like my picture.


So yes I am opposed.

Speed humps are annoying.
Chokers here don't look anything like that, so I don't want them.
http://img129.imageshack.us/img129/4070/img8391.jpg

This is a choker notice the middle median?

They also have what you have pictured above but there is a bike cut out for a bike lane/shoulder like my picture.


So yes I am opposed.That thing is absurd. A bike laned road, that has a speed table for the bike lane, no speed table for the traffic lane, forces bikes to move right, forces motorist to swerve right and into the bike lane; and does nothing to actually slow motorist down. :notamused:

There are speed tables in part of my neighborhood that have cutouts that I can ride through but cars cannot. Another type of speed table is made of asphalt and easy to post over on my bike.

They work so well in slowing down traffic that several neighborhoods request them.

It's no accident that many subdivisions have lots of curvy roads and cul-de-sacs. It slows down traffic.

Narrowing the streets, either with new curbs or with giant concrete planter boxes, has changed a couple of would-be shortcuts for cars into near impassable roads.

Real and fake tv cameras also help. Real cops with radar guns do, too.

Dropping the speed limit helps.

In some neighborhoods, closing a street in the middle or at one end, turning the road into a dead-end, has solved the problem of being a speedy shortcut for motorists.

The problem in California, and perhaps several other states, is that the fastest 1/6 of all motorists determine the enforceable speed limits.

This is only true where the speed limit is not already set by statute, such as for a commercial strip (35 MPH), a residential street (25 MPH) a residential collector (30 MPH?), etc. Most roads and streets fall into such categories, leaving only a few where the limit is determined by an engineering study (and the limit set at the 85th percentile).

Road design is far more effective in controlling speeding than signs and radar guns.

With the exception of speed tables I am generally opposed to traffic calming. The obstacles impact cyclists just as much (and more so w/regard to safety) as other vehicles.
Some examples here:
http://www.tempe.gov/tim/PDFs/FifthStreet.pdf
http://www.tempe.gov/tim/PDFs/13thStreet.pdf

Traffic Calming Manual: http://www.tempe.gov/tim/Traffic/pdfs/STEPManual.pdf

There is also a tendency here to put the bike lane outside the choker, resulting in a death by right hook lane:
http://www.scottsdalepublicart.org/collection/images/TonaleaLandmarksbulbout_photoMargaretBruning.jpg

(http://maps.google.com/?q=tempe,+az&ie=UTF8&ll=33.425397,-111.951813&spn=0.000622,0.000905&t=k&z=20)

Al, I've seen similar schemes to the picture you posted here in Northern Cal. A stupid design indeed.

A further problem with all these measures is that no two parts of "town" ever get the same treatment, as the designs are constantly revised. I have never seen one design that I like - as a driver or cyclist.

Some of the most effective traffic calming I have seen are the electronic signs that flash your vehicle speed back to you. There's one on a road just outside Oxford, just as the speed limit changes from 50 to 30 mph. It flashes either "SLOW DOWN" or a smiley face according to your speed.

Cheers,

Ed

That thing is absurd. A bike laned road, that has a speed table for the bike lane, no speed table for the traffic lane, forces bikes to move right, forces motorist to swerve right and into the bike lane; and does nothing to actually slow motorist down. :notamused:

No it doesn't. It forces motorists to move left and get out of the bike lane. I really like that setup.

I don't understand this idea "traffic calming". Here in Los Angeles the only calming could come from a tranquilizer dart gun, and that only part of the time.
Road design generally RAISES the speed of the road, but seldom lowers it. Most of the streets and roads ARE subject to the survey.
Enforcement lowers it only after a large effort and visible presence and CONTINUING effort and presence.
Next week when the traffic cops are into another neighborhood, the drivers go back to racing like maniacs again.
dc

The idea of traffic calming is to reduce traffic volumes and/or average speed by making a road so miserable to drive on that people would rather take the nearby congested arterial instead of the residential 'short-cut' . Two problems:
One, cyclists are drivers too. The road will be more miserable for them as well, bumps, humps, additional stop signs, constant merging to avoid bulb outs and curb separated bike lanes, features that are hard to see at night even with a good headlight, cobblestones, etc.
Two, drivers (cyclist and motorist) will try to minimize the calming impact of the so called calming measures resulting in even less predictable and less safe driving by all.

With the exception of speed tables I am generally opposed to traffic calming. The obstacles impact cyclists just as much (and more so w/regard to safety) as other vehicles.


There is also a tendency here to put the bike lane outside the choker, resulting in a death by right hook lane:
http://www.scottsdalepublicart.org/collection/images/TonaleaLandmarksbulbout_photoMargaretBruning.jpg

(http://maps.google.com/?q=tempe,+az&ie=UTF8&ll=33.425397,-111.951813&spn=0.000622,0.000905&t=k&z=20)

Is that oak street?
One thing I noticed with Scottsdale, Oak street verified. Is that these are bike shoulders. So you don't need to ride in them.
Another problem with these is the thorny vegetation reaches out to you and you become trapped.

Look folks if ya wanna slow people down, obey the speed limits yourself and set an example. In addition, it forces speeders to pile up behind you, and what could be a more wonderful feeling? My suspicion is this is never seriously discussed in these forums because many of you are closet speeders (nasty nasty! :)) while you drive, for all ya ballyhoo about it when talking cycling.

Damn i forgot to pick up milk at the corner store (vroom vroom!) :)

roughstuff

I always drive the posted 25mph (or less if required for conditions) on the residential streets. It's not just setting an example, but it makes the short cut less desirable - these short cuts only work if folks can speed - the parallel 45mph posted arterials still move at about 25mph average or better in rush hour, so to beat that one has to speed on the short cut.
Actually I think the short cuts are still slower on average, but people would rather drive at a constant 30mph, roll thru the many 4-way stops instead of the alternate 45-55mph between lights and then waiting more than one light cycle at intersections. Also a narrow road with several turns feels faster at a lower actual speed than a straight wide arterial where one can see the traffic backed up at a light a mile away.

I'm not a closet speeder, I'm open about it. But I don't take shortcuts through neighborhoods at ridiculous speeds and other things that make no sense. That's the purpose of traffic calming. If a municipality is trying to calm arterials, they should try to get the traffic moving. Around here, they seem to try to do traffic calming on the arterials by making you stop at every light. This may reduce the average speed, but it isn't calming. It drives about 5% of the motorists insane. It also drives people into residential neighborhoods, because travel is faster, or at least no slower.

After I saw this, I realized the perfect place for a choker is the end of my street. It's a fairly long dead end street, but very wide. People turn down the street thinking it goes through. When the realize it doesn't go through the blast down to the end of the street, turn around, and blast back out. If there was a choker at the entrance to the street they probably wouldn't turn down it in the first place.

The problem in California, and perhaps several other states, is that the fastest 1/6 of all motorists determine the enforceable speed limits.

If by this you mean 85th percentile speeds, that is not correct. The slowest 85% determine the speed. The fastest 15% are ignored.

I always drive the posted 25mph (or less if required for conditions) on the residential streets. It's not just setting an example, but it makes the short cut less desirable - these short cuts only work if folks can speed - the parallel 45mph posted arterials still move at about 25mph average or better in rush hour, so to beat that one has to speed on the short cut.
Actually I think the short cuts are still slower on average, but people would rather drive at a constant 30mph, roll thru the many 4-way stops instead of the alternate 45-55mph between lights and then waiting more than one light cycle at intersections. Also a narrow road with several turns feels faster at a lower actual speed than a straight wide arterial where one can see the traffic backed up at a light a mile away.

+1 Nobody likes being in a sea of cars with a car, it feels like you are trapped or about to be trapped.

here is another view of traffic calming. Note the two types of chokers

http://maps.google.com/?ie=UTF8&ll=33.425509,-111.951818&spn=0.001117,0.001856&t=k&z=19

Portland has been building curb extensions on narrow arterials like crazy. They do nothing for cyclists. Here's what they do do:

1. Preserve a parking lane that could otherwise be converted for use by cyclists

2. Unnecessarily force cyclists out into traffic

Curb extensions are basically road hazards for cyclists as far as I am concerned.

Speed humps are annoying.
Chokers here don't look anything like that, so I don't want them.
http://img129.imageshack.us/img129/4070/img8391.jpg

This is a choker notice the middle median?

They also have what you have pictured above but there is a bike cut out for a bike lane/shoulder like my picture.


So yes I am opposed.


That thing is absurd. A bike laned road, that has a speed table for the bike lane, no speed table for the traffic lane, forces bikes to move right, forces motorist to swerve right and into the bike lane; and does nothing to actually slow motorist down. :notamused:


No it doesn't. It forces motorists to move left and get out of the bike lane. I really like that setup.Look at the left side of the picture, the choker is in the lane (basicly a concrete curb IN the lane. And you do not believe motorist will move right to get farther from that left sided curb??????

http://img129.imageshack.us/img129/4070/img8391.jpg

This design presents a very bad linear hazard for a cyclist.

Look folks if ya wanna slow people down, obey the speed limits yourself and set an example. In addition, it forces speeders to pile up behind you, and what could be a more wonderful feeling?

Agreed, that is satisfying :)

This design presents a very bad linear hazard for a cyclist.

right, this design gives good reason to use the full lane:

...as close as practicable to the right-hand curb or edge of the roadway, except under any of the following situations
3. If reasonably necessary to avoid conditions, including fixed or moving objects, parked or moving vehicles, bicycles, pedestrians, animals or surface hazards.
4. If the lane in which the person is operating the bicycle is too narrow for a bicycle and a vehicle to travel safely side by side within the lane. - check, the distance between the curbs is now to narrow to share.

Al

With the exception of speed tables I am generally opposed to traffic calming.

What about roundabouts and/or traffic circles?

What about roundabouts and/or traffic circles?

For matched designs, some are excellent some are terrible - depends where and why they were put into place.

Portland has been building curb extensions on narrow arterials like crazy. They do nothing for cyclists. Here's what they do do:

1. Preserve a parking lane that could otherwise be converted for use by cyclists

2. Unnecessarily force cyclists out into traffi

Curb extensions are basically road hazards for cyclists as far as I am concerned.

Curb extensions are these at the crosswalks? I think they are intended for pedestrians to cross the street.
http://www.tfhrc.gov/safety/pedbike/pubs/05085/images/fig205.jpg
Pedestrian facilities however annoying should not be looked down upon.

I also found the US gove traffic calming page.
http://www.tfhrc.gov/safety/pedbike/pubs/05085/chapt20.htm

I find it interesting to look at the difference in turning radius at intersections between these two designs. For me I think it is positive to decrease the turning radius as in Wheels pic but in Noisebeam's the turning radius looks to me to be increased, not a positive thing in my book not to mention coming off a mini sidepath just before that kind of intersection.

Which has me thinking there is a difference between taking the lane before an intersection (per Wheel's pic and standard VC practice) and taking the lane mid-block (per typical choker application) and then again at the intersection (for VC principles.) The later seems wrong, out of phase and just plain encouraging the wrong stuff in the wrong location.


Curb extensions are these at the crosswalks? I think they are intended for pedestrians to cross the street.
http://www.tfhrc.gov/safety/pedbike/pubs/05085/images/fig205.jpg
Pedestrian facilities however annoying should not be looked down upon.

I also found the US gove traffic calming page.
http://www.tfhrc.gov/safety/pedbike/pubs/05085/chapt20.htm


here is another view of traffic calming. Note the two types of chokers

http://maps.google.com/?ie=UTF8&ll=33.425509,-111.951818&spn=0.001117,0.001856&t=k&z=19

The only traffic calming devices that are bicycle friendly are traffic circles or closing off streets. Here in Miami, there are several very long two lane roads that run parallel to major arteries that cars were using during rush hour as an alternate to the congested main streets.

The county put traffic circles every few intersections on these roads and now they are barely used by cars, but have become great routes for bicycles. The cars avoid them because the roads are so narrow that it really is difficult getting around the traffic circles and they defeat the car's goal of speeding down the street.

And obviously, closing a street to car traffic is great because you can always get through the barrier on a bicycle.

Chokers are the most dangerous thing I have seen because they encourage cars to make unsafe passes to get in front of bicyclists before they reach the choke point and invariably squeeze the cyclist.

there is one road I ride on fairly frequently that has a choker, I mean pedestrian island, for the purposes of allowing pedestrians to cross the street. There is a nice bike path by the road except that you, of course, have to stop at every intersection; this is not the case on the road. Other than the pedestrian island, the road is plenty wide enough for shared traffic.

I was on a ride in New Jersey recently where a very small rural town had put up chokers. I thought it would be effective except that the targets of the chokers can be expected to perform suicidal moves so they could pass cyclists before the choker.

Pedestrian facilities however annoying should not be looked down upon.

Pedestrian facilities that negatively impact cylists should not be built in the first place. I have heard my share of stories from cyclists that ran into curb extensions, not expecting them to be there. Rule number one - do no harm.

We should not have to choose between hardscape that benefits pedestrians vs. benefits cyclists, if it doesn't benefit both, it should not be built.

They could paint those curb extensions in instead of pouring them in concrete, if they really wanted to.