…or perceived safety and objective safety of the cycle tracks

A study on Toronto and Vancouver (Canada) from [4]: the risk of bike infrastructure separated of traffic is under-estimated. Note the result carried for the cycle track is an aberrant and irrelevant one for reason explained in [8]

Usually, Urban segregated bike lanes (cycle tracsk) are perceived as safer than non segregated one, by many cycle advocates and public alike. Alas most accident statistics say otherwise, and most scientific studies conclude, consistently overtime, that segregated bike lanes impair safety by ~20% ([1] summarizes and complete previous studies, see also a list of studies at [9]), some older studies putting this number up to 4 time higher [2].


    Of course, it is possible to find some studies saying otherwise, but usually those studies show significant methodology shortcomings. To focus only on recent Canada centric examples: [5] draws conclusion on cycle track from a field study conducted in cities not having such infrastructure per sei, as seen in [8] and obvious selction biais discredit results from [3] (more critics here and there):

Montreal, QC: In (3), a separate bike path in a one lane residential street (rue Brebeuf) is compared to an up to 6 lanes thoroughfare (rue st Denis) on a 1km section (Rachel to Laurier), where St Denis has more intersection, and higher speed limit than Brebeuf...to conclude that separates bike lane improve cyclist safety! (no indication of motor traffic volume is provided) -

    The most recent study extended to the USA by the same authors, [10], seems to suffer similar flaws [11].


In urban area, most of the cyclist accidents are due to conflict with motor vehicles (85% in French cities according to the OSNIR), and most of them occur at intersection: In Canadian cities, 50% of fatal accidents and 72% of accidents resulting in serious injury occurred at intersections [12].

Thought, that a separated bike lane can remove potential conflicts along a road, and is recognized to reduce risk in such cases, it makes matter worse at intersections: This is mainly due to the fact cyclists, not on the road, tend to be overlooked by other road users, generating conflict at road intersections. The increased risk for cyclist is illustrated below:

According to some study, the cyclist could be up to 4 time safer on the right side of the street - credit photo (6)CycleRisk

According to (2), the cyclist could be up to 12 time safer on the right side of the street - credit photo (6)

Aware of this fact, Some transportation professional organizations don’t recommend separated bike lane: it is the case for the AASHTO in the USA, or the CERTU for urban area in France. A position supported by numeorus cyclist organizations, be in France (FFCT, Fubicy) or Germany (ADFC), which have been at best rather neutral on the development of segregated cycle track, in some case opposed, and consistently advocating against the mandatory use of it. That eventually became the case for most of the french cycle track, circa 2000. For this later purpose a new road sign has been introduced, and Germany is following track:

B22a_PisteCyclable_obligatoire

The cycle in a blue square sign has been introduced circa 2000: it indicates a recommended cycle track. The cycle in a blue disc indicate a mandatory cycle track ... except of course in UK Which has not ratified the Vienna convention on road sign, from which those signs are derived

An issue is that motorists tend to ignore the difference, and harass cyclists not using the cycle tracks

Traffic engineers, on their side, sometimes eager to remove cyclist of the road for their “good”, have worked to increase the safety of separate bike lane:

Reintroduction into general traffic at intersection

Rennes, France: Bike paths merging in general traffic at intersection, and resuming after it


bikeLaneEntranceBdArmorique Rennes, France (Armorique Bld): Cycle track merging in general traffic at intersection, and resuming after it

Treating cyclist as pedestrian at intersection

MapHongKongBikeLaneIntersec

Hong Kong (Along Ting Kok Rd, Kong Kong NT): Cyclists are expected to walk their bikes to the cycle track... and dismount at every intersections...what by the way is seldom respected in despite of the British style staggered pedestrian crossing! -credit photo left (16), right, Google

Cycling Commuters are generally not impressed by those treatments, which are just slowing down their commute, even when the obligation to walk the bike at intersections (Hong Kong case), is obviously widely disregarded by cyclists using such facilities.

The Copenhagen’s Treatment: Blue cycle crossings

Copenhagen, DK: An intersection where potential conflict zones are highlighted in blue

Copenhagen, DK: An intersection where potential conflict zones are highlighted in blue – credit photo (13)

It has been “invented” in Copenhagen in 1981: The basic idea is to mark the area of conflict between motor vehicles and cyclists so road users pay more attention to this conflict and cyclists have a lane marking through the junction area. Alas, while it is found effectively reducing the number of accidents (and injuries) with one line, it increases it with 2 lines or more, according to [13].

A reason for that is that, it becomes too much solicitation for the motorist than he can process – resulting in an increase of rear ending collisions and red light runnings; and provides a false “sense of safety” to the cyclists, becoming more complacent- not doing head check or using hand signals according to [14]- what is consistent with the “naked street and risk compensation theories.

…and more often that not:

Separated bike lanes come with a panoply of restrictive sign

All, in the name of cycling safety of course…

Left, Bideford UK; center, Harlow UK (now dismantled); right Vancouver, CA - credit photo resp (5),(unknown),(16)

But at the end, it is sometimes better to give-up

…than to cut the trees:


ClosCourtelOld

Rennes, France (Clos Courtel Street): A once mandatory segregated bike lane, has been replaced by a painted bike lane, allowing much better visibility of cyclists by other road users - credit photo Google

Should we be Against the separated bike lane?

or…Should we support the helmet law under evidence of greater safety provided by the helmet

Both generate passionate debates, and unfortunately, both generate biased scientific literature too.

  • Supporters of the helmet laws are because they are concerned by the safety of existing cyclists, they will be obviously against separated bike lanes for the same reason. Not surprisingly, most of the anti cyclist lobbyist will fell in this category
  • Supporter of the helmet laws supporting separated bike lane are not logical with themselves and probably grossly misinformed
  • Opponent to the helmet laws, will explain that, while the safety of existing cyclists is important, it is not paramount- One have to take a more holistic view to assess the benefit/drawback of such safety tool than the existing cycling population- and opponent to the helmet laws, without necessarily denying the positive safety effect of the helmet on an individual, will oppose to a law on the ground that it discourages sufficiently cycling to have a general negative effect for the society.
    Same logic apply to the cycle tracks: there is no need to deny their negative effect on road safety, or to produce biased studies to try to counter evidence, to support them: that is only conductive of complacency with poorly designed cycle tracks which do no good for cycling. Former Vancouver Planning Director, Brent Toderian was able to implicitly recognize the safety issue and supporting it [17]: What is important is to produce evidence that the positive effect they induce outweigh their negative ones

  • [1] Traffic safety on bicycle paths – results from a new large scale Danish study, ICTCT workshop Melbourne, 2008

    [2] Signalreglerade korsningars funktion och olycksrisk för oskyddade trafikanter – Delrapport 1: Cyklister. Linderholm, Leif, Institutionen för trafikteknik, LTH: Bulletin 55, Lund 1984

    [3] Risk of injury for bicycling on cycle tracks versus in the street, Anne C Lusk, Peter G Furth, Patrick Morency, Luis F Miranda-Moreno, Walter C Willett and Jack T Dennerlein, Injury Prevention, February 2011. doi:10.1136/ip.2010.028696.

    [4] Route Infrastructure and the Risk of Injuries to Bicyclists: A Case-Crossover Study, Teschke K, Harris MA, Reynolds CC, Winters M, Babul S, Chipman M, Cusimano MD, Brubacher JR, Hunte G, Friedman SM, Monro M, Shen H, Vernich L, Cripton PA., American Journal of Public Health: December 2012, Vol. 102, No. 12, pp. 2336-2343.

    [5] Safe Cycling: How Do Risk Perceptions Compare With Observed Risk?, Meghan Winters, Shelina Babul, H.J.E.H. (Jack) Becker, Jeffery R. Brubacher, Mary Chipman, Peter Cripton, Michael D. Cusimano, Steven M. Friedman, M. Anne Harris, Garth Hunte, Melody Monro, Conor C.O. Reynolds, Hui Shen, Kay Teschke, Injury Prevention, Canadian Journal of Public Health , Vol 103, No 9, 2012

    [6] Bicycle Quaterly

    [7] Gary James

    [8] Conclusion of both [4] and [5] are drawn from a study carried from May 2008 to Nov 2009 in Toronto and Vancouver. To the bets of our knowledge, it was no “cycle track” in Toronto, and the only ones able to qualify in Vancouver, were an experiment started on July 2009 on Burrard Bridge, with no intersection along the ~1km cycle track segment, and a ~300m segment in one direction on a quiet street (Carral street) with ~300 cars at peak hour with only one very quiet intersection (Keefer street) featuring ~120 car at peak hour (From City of Vancouver’s 2006 traffic count) what is barely representative of a typical cycle track: The result provided for the cycle tracks is hence certainly irrelevant, and that is the reason it stands as an outlier.

    [9] Bicycle Infrastructure Studies review by Ian Brett Cooper

    [10] Bicycle Guidelines and Crash Rates on Cycle Tracks in the United States, Anne C. Lusk, Patrick Morency, Luis F. Miranda-Moreno, Walter C. Willett, Jack T. Dennerlein, American Journal of Public Health, July 2013

    [11] [10] draws conclusion by comparing current crash rate on some cycle tracks with some numbers collected, sometimes in specific situation- like a study on Boston’s bike messengers- more than 10 years ago, without correcting them of external factors, like significant general crashes reduction rate in the last decade, and well documented safety in number effect affecting more particularly the cyclists. Furthermore, one could argue that the “crash rate” is a very poor, if not uncorrelated, proxy, to qualify the safety of a road infrastructure: Roundabout are well-known to increase the rate of crashes, vs a signaled intersection, but they are also well recognized to reduce the risk of serious injuries, most of the crashes being limited to fender-bender type. In other word, a crash rate ratio is not representative of the safety social cost of an infrastructure…what ultimately matter. More awkward [10] suggests that “The AASHTO recommendations may have been influenced by the predominantly male composition (more than 90%) of the report’s authors” without being able to substantiate this assertion, showing that we have here more a opinion paper: attacking the gender of authors to disqualify their works, seems pretty petty at best!

    [12] Vulnerable Road User Safety: A Global Concern, Transport Canada, 2004.

    [13] Safety effects of blue cycle crossings: A before-after study, Søren Underlien Jensen, Accident Analysis & Prevention, Volume 40, Issue 2, March 2008

    [14] Evaluation of Blue Bike-Lane Treatment in Portland, Oregon. Hunter,W.W., Harkey, D.L., Stewart, J.R., Birk, M.L., Transportation Research Record 1705, 2000

    [15] The finding of [13] seems in fact to suggest that the increase in accident and injuries are mainly among motorists, and eventually moped: so that in fact the blue line could effectively be not than “unsafe” for cyclists. Unfortunately, the paper doesn’t provide detailed break down of the injuries according to the transport mode. In any case, the measured global effect is a negative one

    [16] www.vivendesign.com

    [17] Vancouver Embraces Bikes, Adds Lanes, Tim Newcomb, Planning;, Vol. 77 Issue 2, Feb2011

    Park Avenue

    May 21, 2010

    Avenue [ˈævɪˌnjuː] from the old french arrival, has eventually got a different meaning in english, as well as in current french, due to the current usage we give to it nowadays.

    Here after is a very simplified history of it:

    XVIII century

    At the eventual difference of other roads or streets, avenues were usually work of urban planning, and primarly designed as radial promenade at the edge of the city with function to great in a ceremonial way the arriving visitor

    Avenue du Mail, Rennes, France. concept plan from the XVIII century. the leisure aspect is the dominant factor, at the expense of the mobility one. credit photo (1)

    XIXcentury

    Though that not matching to the original vision, the primary promenade function is still well respected.

    The same location at the turn of the century. The leisure aspect of the promenade is still well alive

    XX century

    The advent of the automobile and other social change will involve deep cultural shift:

    • Urban people will eventually prefer spend their free time elsewhere than lingering on the street becoming less pleasant due to the surrounding roaring motors and gas smell (we don’t speak to much pollution those day).
    • the free space is then occupied by the new mobility device

    With the advent of the automobile, the promenade change of function! (it is still Avenue du Mail, lately renamed Mail Francois Mitterrand, Rennes France)

    XXI century

    Another relative cultural shift appears in the 80s, eventually learning of the american experience: it appears very apparent that the adaptation of the European city to the car has no future: and a better use of the scarcely city’s available real estate need to be devised. the LRT, trams in Europe, will be part of the solution, and the large French avenues, will be ideal Right of Way candidate. The vision of the future century is then eventually represented by this artist rendering:

    the future Starsbourg tram, line F, riding on what used to be a parking lot...at least in the recent history. credit photo (5)

    One will note, it is pretty seldom to see modern tree lined trams, eventually for the following reasons:

    • the tree roots system could compromise the integrity of the trackbed
    • the tree branches could interfere with the overhead wires
    • the falling tree leaves could grease the rails, compromising the acceleration/braking capabilities of the train

    In the Strasbourg F-line case, those aspects are mitigated by the integration of the bike path along the tram ROW. the integration of the bike path is an addition to the late LRT project.

    Obviously, the vision is a significant progress on the current situation, in the sense it returns to a pleasantly greenish aspect of the avenue.

    The park and ride model

    Where we should not give more credit to the french than they deserve is here:

    • In most of the case the space allocated to the automobile traffic is not compromised, and the Strasbourg example shown above is basically no exception to the rule: while that the parking space is removed at the benefit of the trams, there is no reduction in automobile traffic lanes benefiting then of a freer flow, since not impeded by car looking for or negotiating parking spot
    • there is no increase of space for pedestrians, and the leisure and social interaction aspect, like lingering on the street, is not part of the picture either

    The removal of parking space could be considered as a progress, but usually, a french tram projects barely means reduction of parking space either, but rather relocation of it according to the well known park and ride model.

    The picture below feature one P&R in Bordeaux having 603 stalls [6], more than at the Canada line Bridgeport one [7]. Bordeaux has 14 other structures like this along its 3 trams lines…


    park and Ride in Bordeaux, france. Notice the state of the track's lawn as soon as you get out of Downtown. credit photo (6)

    One can clearly suspects that the motivation to introduce trams in the french cities has not been to challenge the general car centric culture, but was more guided by more pragmatic space constraint requiring a P&R model in order to preserve good vehicular movement on the city arteries and accessibility of the city to an ever greater number of people, including by car.

    In that aspect, it has been a more successful model than the US one, eventually due to the greater scarity of

    • downtown parking stall
    • road access

    and,

    • the preserved heritage specificity of the European cities could have contributed to maintain the attractiveness of their downtown in despite of access impediment
    • the short length of the European trams line, typically not venturing much farther than 5km from he town center, allow for short trip time, in despite of relatively low average speed [4], the later allowing good integration in the urban fabric

    All those factor, in addition of social one going beyond the scope of this post, could have saved the middle size European city to know the fate of their American sister cities, in term of Downtown life.

    But, if one considers the public transit market share in 14 french urban areas with LRT; 11% (for weekday trip) [8]; it is hard to speak of a successful strategy, to be emulated.

    At the end of the day, the avenue original vision, which cheer size was to provide “park” space for people, devoided to be “park” space for transportation device, has not been restored. Indeed it is now used to “segregate” space according to transportation modes (in a vision where “lingering” is also a “commercialized” activity at the benefit of the sidewalk coffees).

    It is a progress on the dictatorship of the automobile reign, and it is possible that the LRT has been an ingenuous tool to legitimate the displacement of the cars toward the outer edge of the city, but is the result the most efficient allocation of the city surface space? or in other term, is it the best we can do?


    [1] from archives municipales de Rennes, France

    [4] Average speed of european trams is usually below 20km/h, 18.5km/h in the above mentioned case of Bordeaux

    [5] from Tram-Train/Tram F, Strasbourg-Bruche-Piémont des Vosges, June 2008

    [6] Picture and number from le tram de Bordeaux”

    [7] Bridgeport park has 600 stall for Canada line rider according to Translink

    [8] Transportation mode share of 14 metropolitan area with tram in France, from “Les deplacements a Nantes metropole Etude N 80, decembre 2009, Insee Pays de Loire, France citing “enquêtes nationales transports et communication 1993-1994, transports et déplacements 2007-2008″, Insee, SOeS and Inrets.

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