Tag Archives: cycle tracks

Monsere, Dill et al. — Not Yet a Review, But…

M. Kary, who prepared a review of the Lusk et al Montreal study, has had a preliminary look at the Monsere, Dill et al. study of barrier-separated on-street bikeways (“cycle tracks”) which the bicycle industry lobby PeopleforBikes is promoting as demonstrating their safety. Dr. Kary has given me permission to publish his comments here.

An Introduction To and Overview Of:
Monsere C, Dill J, et al. (2014) Lessons From The Green Lanes: Evaluating Protected Bike Lanes In The U.S. Final Report, NITC-RR-583

To begin with a platitude: traffic accidents are rare events. The totals are large only because the overall volumes of exposure are huge. Therefore, if considering safety in terms of outcomes rather than the underlying mechanisms of operation, any facility, no matter how poorly designed, will appear safe if examined over a short period of time.

But collecting data over a long period of time has its disadvantages too: not just cost and delay, but also the averaging, and therefore blurring, of the effects of various changing causes and circumstances. Nor does it work at all for facilities that are yet to be built. In response to these problems, engineers developed the methods of traffic conflict analysis. They can be seen as based on the following logical and kinematic necessities. First, in order for a collision to occur, the vehicles involved must eventually get on a collision course. Second, in order to get on a collision course, they must first get on a near-collision course. On the other hand, not all vehicles once on collision or near-collision course do end up colliding: their operators make course corrections and avoid that outcome. Such potentially dangerous but often ultimately safe trajectories, i.e. traffic conflicts, occur much more frequently than actual collisions, deaths, or injuries. If there exists a suitable relationship between the former and the latter, then conflict analysis can be used to study road safety at reduced cost, with better timing, and even via simulation modelling of facilities that have been designed but not yet built.

The theory and practice of conflict analysis for motor vehicles has been developed over something like a half a century of research. This has evolved to quantitative methods using not just traffic cameras, but also instrumented vehicles, automated data extraction, and theoretical concepts such as time to collision, gap time, gap acceptance, post-encroachment time, and many others. There is no such corresponding body of research for bicycles. Even if there were, it could never be as important to bicycle or pedestrian deaths and injuries as it is for the occupants of cars and trucks: for example, the latter vehicles never topple over at stops or just slip and fall, so that their occupants fracture an arm or strike their heads on a curb. In fact the majority of bicyclist injuries, even those requiring hospitalization, apparently involve only the bicyclist, making conflict analysis entirely or at least largely irrelevant to them.

On the other hand collisions with motor vehicles are major factors in cyclist deaths and injuries, and they are what cyclists worry most about. And even apparently bicycle-only crashes can be provoked by e.g. general fears or specific intimidations, or avoidance manoeuvres leading to loss of control. Thus there are also dimensions of traffic conflicts applicable to bicycling, but either inapplicable or less so to motor vehicle-only conflicts. Nor is every conflict visible or strictly kinematic: consider for example the effects of sudden and loud horn honking or engine revving.

With these fundamental limitations in mind, obviously traffic conflict analysis is a promising method for investigating important aspects of bicycling safety. The theory needs to be developed, so we can figure out what constitutes a high or low rate of conflicts, what types of conflicts figure what way into which accident types, and how vehicle operators and pedestrians cope with them, such as through hypervigilance, or avoidance of the area and thus diversion of problems to a different one.

Not only does the theory need to be developed, but also the methods of data extraction and analysis: the subjective review of traffic camera recordings, typically of low quality, is a mind-numbingly tedious, labour-intensive and error-prone task, that does not scale well.

The work of Monsere et al. (2014), Lessons From The Green Lanes: Evaluating Protected Bike Lanes In The U.S., should be considered a pilot project in this effort, although the authors themselves do not describe it as such.

Monsere et al. aimed to address six questions:

  1. Do the facilities attract more cyclists?
  2. How well do the design features of the facilities work? In particular, do both the users of the protected bicycle facility and adjacent travel lanes understand the design intents of the facility, especially unique or experimental treatments at intersections?
  3. Do the protected lanes improve users’ perceptions of safety?
  4. What are the perceptions of nearby residents?
  5. How attractive are the protected lanes to different groups of people?
  6. Is the installation of the lanes associated with measureable increases in economic activity?

Apart from noting that, as with most sociological research, their survey response rates were dismally low (23-33% overall, counting even only partially completed surveys as full responses), to produce a socioeconomically skewed sample (e.g. the bicyclists being 89% white, 68% male, 82% having at least a four-year college degree, and 48% with annual incomes over $100,000)— this overview of their work considers only the first part of their question No. 2.

Monsere et al. installed video cameras along short bicycle sidepaths (“protected lanes”, “cycle tracks”) constructed between approximately the summer of 2012 and the early summer of 2013 as part of the Green Lanes Project. These were in four U.S. cities, San Francisco (two 0.3 mile paths), Portland (one 0.8 mile path), Chicago (0.8 and 1.2 mile paths) and Washington (a 1.12 mile path; no cameras were installed in Austin, although sociological surveys were conducted there). They did their video recording chiefly at intersections, six in these four cities in the summer and fall of 2013. This was then presumably while the users were still in a cautious or exploratory state, as they got used to the new facilities.

Only 12-18, or in one case 20, independent hours of video were analyzed from each intersection. As each intersection examined was given a unique treatment, results cannot easily be pooled. These are very small numbers.

(This makes for substantially less than 120 hours total. The authors seem to say they analyzed 144 hours of video at intersections. This would mean that some of this total came from multiple cameras examining the same intersection at the same time. The authors do show frame captures from some of their cameras. This observer would find it difficult to correctly identify the conflicts from the views on display.)

As noted following the opening platitude, any facility, no matter how poorly designed, will appear safe if examined over a short enough period of time.

The six facilities examined were all so new (less than or little more than a calendar year old) that there were no injury or death data available for them. (For comparison, the entire city and island of Montreal, with all its thousands of intersections, averages of late about five cyclist deaths and 25-50 police-recorded serious cycling injuries per year.) Thus, there would not have been a way to use even many more hours of recording to examine for any relationship between the surrogate outcomes (conflicts, violations or errant behaviours) and the outcomes of most interest, deaths and injuries.

Further, as this was neither a before-after study nor a comparison with standard intersections, there is no way to know whether the numbers of observed conflicts, violations, or errant behaviours, were themselves high or low.

As to the actual results from this pilot project, the much touted headline was that there were only six minor conflicts found, out of nearly 12,900 bicycle movements through intersections. The most basic problems with this headline are:

1. It is the wrong comparison. The conflict rate has to be the number of conflicts divided by the number of occasions where at least two users capable of conflicting are present, e.g. a bicycle and at least one other bicycle, pedestrian, or motor vehicle. Thus the authors give figures of 7574 turning motor vehicles, but only 1997 turning motor vehicles with bicycles present. The corresponding conflict rates (which they normalize by the products of bicycle and motor vehicle movements, not by the numbers of bicycle movements alone) they give for the individual intersections therefore vary by factors of approximately 3 to 10, depending on which figures are used.

2. Six is the total of observed “minor” conflicts, not the total number of observed conflicts. There were also 379 “precautionary” conflicts with motor vehicles, 216 with pedestrians, and 70 with other bicycles.

3. Besides conflicts, there were numerous violations or other errant behaviours: e.g. 9-70% of bicycles and 7-52% of turning motor vehicles in the various intersection designs used the lanes incorrectly, 1-18% of turning motor vehicles in the various mixing zone designs turned from the wrong lane, 5-10% of motorists turned illegally on red arrows at intersections with bicycle-specific signals, and 7-23% of bicyclists disobeyed their signals.

4. Without any theory or model of how any of these occurrences or their frequencies relate to death, injury, or property damage, and without any before-after or non-sidepath comparison data— not to mention, with the very small numbers of observation hours— there are almost no safety implications, positive or negative. The only concrete result is that one of the local authorities apparently deemed the problem of motor vehicles turning from the wrong lane (18%), straddling lanes (another 17%), or entering the turn lane early (15%) to be so severe that they later removed the intersection treatment and replaced it with another design (at Fell and Baker in San Francisco).

5. The sociological surveys tell another story: one-third of all bicyclists surveyed said they had been involved in at least one near collision on the paths, while 2% experienced an actual collision. 23% had a near collision with turning cars, 1.8% an actual collision with turning cars; 19% a near collision with a pedestrian, and 0.4% an actual collision with a pedestrian.

In short: this is an interesting pilot project, whose methods are impractical for the amount of data collection needed for meaningful safety results. Even with better methods, conflicts are only one facet of the bicycling, and overall safety picture; while road designers and road users, whether bicyclists or motorists, have to consider more than just safety. Convenience, transit time, cost, and greenhouse gas emissions also matter. A cycle track that, like the downtown de Maisonneuve track in Montreal, lies largely dormant in the winter, but delays motor vehicle traffic in the winter and ties it up spring, summer and fall, will be of no help in reducing CO2 emissions. The much touted headline results from this study are selective, overblown, and misleading. Any facility will appear safe if examined over a short enough period of time, and surely 12 to 20 hours each is short enough

Godzilla’s toothpaste decorates Seattle bikeway

A new bikeway has recently opened on Broadway in Seattle, Washington state, USA.

Someone has posted a video of a ride on the newly-opened bikeway.

(To get a better view of the video, click on “YouTube” and open it up full-screen.)

This is an uphill ride, very slow in most places. Traffic was light on the street, and even lighter on the bikeway. It will be interesting to see how the situation develops when traffic is heavier.

The bicyclist who made the video is clearly aware of the hazards, as he or she repeatedly checks for turning traffic before crossing intersections. Others might be more naive.

What most catches the eye though about this installation is the “Godzilla’s Toothpaste” barriers between the bikeway and parking spaces — an artistic touch, to be sure, though also a collision hazard, and sure to be pummeled by cars pulling into parking spaces. The toothpaste is visible a few seconds from the start of the video and also later.

As described by Seattle cyclist Joshua Putnam, the installation of the bikeway followed from a series of events, like a chain of dominoes falling over, except that some the dominoes were bicyclists. The first of these events was installation of a light rail line in the street. Then, bicycle crashes became much more frequent.

Light rail lines in streets are a serious hazard for bicyclists, from wheels’ getting caught in the flangeway, and from bicyclists’ having to choose their line of travel to avoid that risk. The problem is worsened by the tracks’ curving over to the edge of the street at stops — necessary so there can be a raised platform and wheelchair access.

To address the hazard it created with the trolley tracks, Seattle installed a two-way, one-side-of-the-street bikeway, on this two-way street. Such bikeways pose problems anywhere, due to the increased number of conflicts and unusual movements at intersections — but also much of Broadway is steep, and bicyclists traveling opposite the usual flow of traffic on the bikeway are going downhill. Crossing an intersection or driveway from right to left on the near side has been well-established as highly hazardous.

Before the trolley tracks, before the bikeway, bicyclists could travel downhill as fast as the motor traffic. Now, the safe speed is hardly more than walking speed, and with repeated checks for crossing and turning conflicts. As is the usual practice, large swatches of green paint have been spread on the street to demarcate zones where bicyclists and motorists operating according to their usual expectations are concealed from each other until too late to avoid collisions.

Motorcyclists also are at risk from the trolley tracks, but they are excluded by law from the bikeway.

Danish story, video and comments on the Albertslund-Copenhagen “bicycle superhighway”

A reader pointed me to a news story on the politiken.dk blog about the Copenhagen/Albertslund “bicycle superhighway” which is getting attention and publicity. The reader’s comments on my previous post read:

Yeah, its kind of joke, but to be fair they are not called superhighways in Danish but Super bicycle tracks, and even then most agree that they are not really that super. There is a video of the entire route here if you scroll down a bit:

http://politiken.dk/debat/skrivdebat/ECE1615543/er-koebenhavns-nye-cykelsti-virkeligsuper/

The two next ones which will open are another story though, as they mostly have their own right of way, and use viaducts or bridges to cross streets.

So, better things may be on their way, but…I ran the article through the Google translator, and it appears in the link below in (sort of) English. The page includes the sped-up video of the entire route.

http://translate.google.com/translate?sl=auto&tl=en&js=n&prev=_t&hl=en&ie=UTF-8&layout=2&eotf=1&u=http%3A%2F%2Fpolitiken.dk%2Fdebat%2Fskrivdebat%2FECE1615543%2Fer-koebenhavns-nye-cykelsti-virkelig-super%2F&act=url

Here’s the video — warning, Shell diesel fuel ad at start, and you can only stop the video when you click on it, see the ad again and click on it to open a bigger ad! This workaround was needed to make the video visible on this page.

The one unifying factor of this route is an orange line painted lengthwise to identify it. The first part of the route is relatively tame. Barriers, unprotected intersections and other hazards pile up near the end.

Some representative quotes (I’ve translated from Googlish to English, thanks to an online dictionary and my knowledge of the neighbor language, German.):

From the article:

“I did not expect that I just had to detour on ordinary roads in residential neighborhoods. I did not see much of the green wave that is supposed to be in town. I do not think you can call it a super bike path,” the [politiken dk test rider] concluded.

From comments on the article:

- The section of tunnel under Motorring 3 is dark and miserably lighted. There are many riding schools (which, incidentally, should be forced to close and move out into a rural area!). The tunnel is usually filled with horse s***, and because you can not see in these tunnels due to poor lighting, you can only hope that you do not ride through any of it.

*****

- In the westbound direction, at the pitch-dark tunnels, you have to negotiate two sets of barriers. The point of these, other than to impede traffic, I do not know. But when you have to use all your mental energy to get through these, they constitute more of a hazard than a safety precaution.

*****

I have commuted between Roskilde and the northwest part of Copenhagen 2-3 times a week on a recumbent trike with an electric assist motor for 6 months (http://ing.dk/blogs/pedalbilen). When I used the “super path” the trip was about 3 km and 15 minutes longer. Especially the part of the route in Albertslund is very indirect and inconvenient. There are detours, barriers and ramps in most places, and it will for example not be possible to ride in a velomobile, as far as I can judge. The new route is comfortable and free of exhaust, but as commuter route it gets a failing grade compared with Roskildevej [a parallel, 4-lane divided but not limited-access highway with one-way sidepaths].

*****

- I didn’t see anything which shows that cyclists have priority over the other traffic. Unfortunately, the only thing new that I see is approximately 100 meters of new asphalt in two places near Rødovre, so that it is easy going. There are simply no real improvements for cyclists in relation to other road users! You can still find barriers, sharp turns, bumps and traffic lights. Why is there no new cycle path, e.g. along the western forest road, so you do not have to drive through neighborhoods with pedestrians and children playing? Why are barriers not turned 90 degrees, so users of the route have right of way?

Even if there were brand new asphalt on the entire route it would never merit the title “super”. Only when a route enables more or less continuous travel at high average speed (which motorists know from motorways) does it, in my opinion, deserve the massive marketing it is currently getting.

*****

…Bus passengers cross the bikeway. It seems quite unreasonable that there are no islands at bus stops where passengers have to wait when they get on and off. Thus cyclists must stop, and so, so much for the “super bike path”.

Such language!

The following are my comments on a post on P. M. Summer’s CycleDallas blog. I’d have liked to post my comments there, but they are longer than allowed by the software on Summer’s site.

Quoting Robin Stallings, Executive Director of the Texas Bicycle Coalition:

We have tried to answer your inquiry from a ‘legal’ point of view below.

Leslie Puckett, our legal fellow, prepared the answer with some input from Mark Stine and I. This should not be construed as legal advice. Consult an attorney for that.

The word “legal” in quotes — the nominative “I” as the object of a preposition — trivialities? Maybe, but on the other hand, grammatical errors can drastically alter the meaning of laws. Indeed, consult an attorney, but Stallings and his advisors didn’t!

The short answer of BikeTexas’ interpretation of the current law is that:

“If the bicycle lane is considered part of the roadway, then, TTC 551.103, which requires a cyclist to ride as far to the right on the roadway as possible, would seem to require a cyclist to ride in the bike lane (or paved shoulder) except when it is obstructed or when turning left, since the bike lane is usually on the right side of the roadway. The law is appropriately ambiguous and leaves discretion to individual cyclists to determine for themselves if the bike lane is obstructed and is usable.”

Stallings appears to be unaware that the bike lane, but not the shoulder, is part of the roadway. Also, Texas law requires a cyclist to ride as far right as practicable, not “possible”, and with additional exceptions he doesn’t mention. These are important distinctions in the light of the Reed Bates arrests in Texas. Stallings knows of these arrests.

I leave out the list of studies that Stallings cites — Summer has addressed that.

There are no examples of cities that we are aware of, in Texas or the nation, where the mainstream bicycle advocates regret the installation of, or are calling for removal of bike lane networks.

Bethlehem, Pennsylvania, to give an example…Stallings also changes the subject, “where is it legal to ride?” to “mainstream, knowledgeable (!) people like us support bike lanes everywhere and if you don’t, you’re a weirdo.”

However, protected bike lanes, also known as “cycle tracks”, are replacing bike lanes in many cities.

Stallings floats a topic that has nothing to with the original question — he gets to sound more authoritative to an uninformed audience, and to use the word “protected”. This originally applied in traffic engineering to, for example, a left-turn signal phase where the opposite-direction traffic has a red light, but now, instead, it is applied to a bikeway behind parked cars, with the attendant poor safety record due to crossing and turning conflicts and sight-line obstructions. It is a path — but calling it a bike lane lends it the aura of the familiar. The uninformed, or misinformed, will assume that it offers real protection. They are also introduced to a new buzzword, “cycle track,” which may have been unknown to them.

Sharrows are in use in many cities where there is not enough right way to accommodate bike lanes.

Shared lane markings, not the obsolete “sharrows” — are indeed used, but to refer to them and bike lanes as the only alternatives narrows the discussion, now doesn’t it?

Let me know if you have any more questions.

OK, then, why, Mr. Stallings, are you resorting to classic techniques of manipulative use of language? On that topic, allow me to recommend Prof. S. I. Hayakawa’s classic book Language in Thought and Action and to quote Robert Jay Lifton:

“The language of the totalist environment is characterized by the thought-terminating cliché. The most far-reaching and complex of human problems are compressed into brief, highly reductive, definitive-sounding phrases, easily memorized and easily expressed. These become the start and finish of any ideological analysis.”

Ciccarelli on cycle tracks

John Ciccarelli is a consultant on bicycling and a League of American Bicyclists-certified cycling instructor who specializes in teaching adults who have never ridden a bicycle before. His comments here are reprinted by permission, and are in response to an e-mail he cites.

Subject: Re: Making Cycling Irresistible: Lessons from the Netherlands, Denmark, and Germany
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Safe separation with the Copenhagen curb?

How does a Copenhagen cycle track make bicycling safer? By putting bicyclists behind a low curb, a curb which a motor vehicle with its big tires can mount, but a bicycle can’t. The curb increases safety for bicyclists the way a streetcar track does.

Copenhagen curbed cycle track

A cyclist rides on a Copenhagen cycle track. Google Street View photo.

Oh, but wait — a streetcar track is a hazard to bicyclists, isn’t it?

So, let’s try to figure out the logic behind the Copenhagen curb. I think that it goes something like this:

“Bicyclists are sort of halfway between pedestrians and motorists, so we’ll put them behind a little curb about half as high as the sidewalk.”

This is reasoning by analogy. Reasoning by analogy is perilous if the analogy doesn’t hold. This one certainly doesn’t, so let’s look a little bit deeper.
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