“Many studies of bicycle tracks have been undertaken in Northern Europe. A meta analysis of 11 studies shows a reduction of 4 percent in crashes, and the crash reduction is almost the same for pedestrians, bicyclists and motorists respectively.”
The meta-analysis being referenced there is from, “The handbook of Road Safety Measures,” by Rune Elvik. Meta-analyses are useful because they take a broader consensus from numerous studies, minimising the effect of any flaws or limitations in individual studies by looking for overall trends in the body of work as a whole. Picking a single piece of research which agrees with your own opinion whilst ignoring the wider consensus offered by the body of literature is called “Cherry-picking,” and is generally frowned upon.
The study compares the numbers of cycle*-car and cycle-pedestrian crashes on roads with cycle tracks and with cycle lanes, to predicted crash figures based on figures for unaltered roads which have been altered to factor in the alteration to traffic volume and composition. The crash figures for junctions and straight road sections are treated separately, and the study finds that on roads with cycle tracks, cyclist crashes are decreased by 13% on straight sections, whilst at intersections they are increased by 24%. Overall, crashes involving cyclists increased by 10%.
This is the oft-cited percentage increase when discussing Dutch-style segregated cycle facilities with those who are vehemently opposed to them, and it is interesting to see how it is calculated; previously cyclist injuries at junctions had been measured as 353. After the installation of cycle tracks, the number of cyclist injuries at intersections was measured as 285, a reduction of 19% in absolute figures. However, the 24% increase figure is calculated from a predicted number of crashes figure for the after period, based on the changes to the traffic volume and mode composition, which predicted that at unmodified intersections with the same increase in cyclists, decrease in motorists and subject to pre-existing crash trends seen at the intersections which had been modified with cycle tracks, there should be 230 cyclist crashes. This is the figure which is used to generate the eye-catching 24% increase in crashes figure. The author of the paper also states that:
“The construction of bicycle tracks resulted in a 20 percent increase in [bicycle] traffic mileage and a 10 percent reduction in motor vehicle traffic mileage on those roads, where bicycle tracks have been constructed.”
Taking intersections and straight sections together gives a figure of a 10% increase in crashes involving cyclists overall versus the predicted figures on un-altered junctions for the same traffic mode/volume composition (broadly speaking, a 10% reduction in motor traffic and a 20% increase in cycle traffic), a composition which is arguably only achievable where segregation is applied. The actual before and after numbers show a decrease in the absolute numbers of cyclist crashes of 29%. It is important to consider the effects of any pre-existing downward trend in crashes which could be contributing to this number, but also important to consider that this effect is seen contemporaneously with an increase in cyclists’ mileage of 20% on these facilities.
“The bicycle facilities effects on traffic volumes are rather large. We do not know for sure whether these effects are a result of changes of route choice or transport mode choice or both. The magnitude of the changes in traffic volumes on the reconstituted streets, and the traffic volumes on parallel streets, however, do indicate that thousands of travellers in total must have changed their choice of transport mode. We do not know who have shifted mode – children, middle-ages or elderly, women or men, beginners or experienced, etc.”
It is also interesting to note the large effect which the presence or absence of car parking restrictions on the adjacent road has on the number of collisions and injuries for cyclists and pedestrians which occur at intersections. Where parking restrictions were in place, there were more collisions due to the effect of motor vehicles parking on minor roads instead, resulting in more turning thus collisions.
At the beginning of this post, I stated that the safety effect of Dutch-style segregated cycle facilities is actually rather unimportant. Cycling, even on our hostile road network is actually a very low risk activity. A lot of people have invested a lot of time in trying to convey this message, that cycling is actually very safe, low risk and that the benefits from cycling hugely outweigh the risks a person is exposed to by cycling. It also featured as a common theme on the Cyclechat thread too, demonstrations of the statistically low risk which comes from in motor traffic and links to works such as the study discussed above (ignoring the wider consensus offered by the overall body of literature, which are even discussed in the introduction of this particular study).
Generally, the body of research shows that Dutch-style segregated infrastructure moderately decreases the risk to which cyclists are exposed, despite expanding the demographic itself from what is largely a small minority of experienced and vigilant hardcore cyclists under a vehicular approach, to include such disparate groups as teenagers chatting as they ride together or riding alone with earphones in, older people, parents with their children (either on their own bikes or on the parent’s bike), children cycling to school without the need for supervisions and boozy revellers returning home from a pub or club by cycle. Despite the incredible broadening of the demographic, safety is still increased.
However, all of this is missing the point. Surprisingly, the main benefit and purpose of implementing Dutch-style segregated cycle infrastructure isn’t just to reduce risk, it is to reduce fear. Increasing people’s sense of subjective safety is a huge part of making the bicycle seem like an attractive and viable mode of transport to them. Another important factor is convenience. Both the need to feel safe whilst cycling, and the need for it to be convenient are provided where there are Dutch-style segregated facilities (and the extra options it opens up for reducing the speed, volume and permeability available to motorised traffic). All the statistics demonstrating the low-risk of vehicular cycling isn’t going to change the average person’s mind as long as it doesn’t feel safe to them. People don’t work that way
“Making these bicycle facilities must have contributed to benefits due to more physical activity, less air pollution, less traffic noise, less oil consumption, etc. […] The positive benefits may well be much higher than the negative consequences caused by new safety problems.” (My emphasis)
*In the study, numbers for cycles and mopeds limited to 30 km/h (which are legally permitted to use cycle tracks in Denmark) are bundled together. Make of this what you will.
1) We’ll never get segregation on every street.
2) There isn’t room on British streets for separate cycle facilities.
3) People need somewhere to park their cars.
1) We’ll never get segregation on every street
In The Netherlands (and Denmark for that matter) they don’t even come close to having separate facilities for cyclists on every street. Instead they have specific guidelines for how much separation is required in a given location (Separation Principles) based on factors including the importance of said route as a main commuting route for cyclists, the volume of motorised traffic on said route and the speed of motorised traffic on said route. The degree of separation increases with all of these factors, from zero segregation on a quiet service road up to wide separated cycle lanes all red traffic signal phases at functions to allow cyclists and pedestrians to turn in whichever direction they wish at junctions, or roundabouts with radial exits and legal priority for cycle traffic.
An advantage of this type of infrastructure is its calming effect on motor traffic, due to the reduction in motor traffic capacity. This has obvious benefits for pedestrians without bringing cyclists and motorists into conflict in the way that conventional lane narrowing does, as it is usually implemented without any serious consideration for the needs of cyclists.
2) There isn’t room on British streets for separate cycle facilities.
Now that we have addressed the myth that Dutch-style infrastructure means putting a separate cycle lane on every street, we have gone a long way to addressing canard number two. The roads which most unattractive and unsafe for cyclists at present are the very same roads which have require the very highest level of separation of cycle and motor traffic under the rules of the Separation Principles. These roads are the widest and fastest roads we have, roads which are easily capable of accommodating Dutch-quality separate infrastructure for cyclists. In Manchester, good examples of roads matching this description include Upper Brook Street (A34), Oxford Road (B5117), Princess Road (A5103), Chester Road (A56) & Regent Road (A57), to name a few. Reducing the speed and volume of motor traffic reducing road capacity on these streets has wide-ranging benefits to pedestrians and the local community in which these roads are situated.
Unlike current approaches to tackling motor traffic speed and congestion through road capacity reduction and lane narrowing, using the space taken away from motor traffic to build Dutch-quality infrastructure does not necessitate bringing cyclists and motor traffic into conflict and so enhances the attractiveness and convenience of cycling rather than further diminishing it.
3) People need somewhere to park their cars.
Ignoring for now the obvious oddity that is the widely accepted phenomenon that is the routine storing of personal property on the public highway, in addressing canard number two, we have gone a long way to tackling this one too. The streets I named are generally of the kind which have either blanket parking bans, or at least have peak-hours parking bans along most of their length. The biggest roads are the roads where parking is already prohibited all the time, and where it is not prohibited all the time, it definitely should be (I’m looking at you, Upper Brook Street).
Even if implementing Dutch-style infrastructure did mean displacing some established car parking, I don’t see why this should be regarded as a problem. It is a very depressing prospect that the safety of vulnerable road users be regarded as a lower priority than the publicly-subsidised storage of personal property on the public highway. Streets are primarily intended for people and movement, not storage.
Recycling in the 1990s was possible, but it required individuals to think about their domestic waste and make the conscious effort to elect to take their waste to centralised recycling facilities. The more destructive option of not recycling waste which could have been recycled was the convenient and easy choice because it didn’t involve individuals to elect to change their behaviour. Most people didn’t particularly care about the issue of recycling and thought nothing of throwing all their domestic waste out in the same bin. Less than twenty years in 2011, almost everyone recycles the majority of their recyclable domestic waste.
In 2011, do the majority of people care about the issue of recycling? The answer is still a resounding “No.” People recycle because it in 2011 it is easy and convenient for them to do so, so it is the natural choice. Rather than continuing to promote elective behavioural change to increase recycling rates, councils have changes the waste collection infrastructure to make recycling the natural and convenient option. Separate bin facilities are provided for different sorts of waste, often different categories of recyclable waste in addition to a general waste bin for non-recyclable material. For those choosing not to separate waste so it can be recycled, life is made inconvenient by a reduction in general waste capacity through reducing the frequency of general waste collections. Overall capacity is maintained or improved through additional collections for recyclable waste, making recycling a convenient and attractive option. Mass recycling was brought about not through elective behaviour change but through subtle coercion; changes in the waste collection infrastructure were made so that recycling became attractive and convenient, whilst not recycling became a less attractive and less viable option.
Those who wanted to promote recycling realised early on that an approach based mainly on elective behavioural change was inherently limited in its ability to deliver significant gains in recycling rates. Elective cycle training, “Be nice,” and “Mutual respect,” campaigns directed at both motorists and cyclists, and things like Bike Week are all similarly limited. A few weeks after the end of “Can collection month,” I had a bag of cans I wanted to recycle, but because the waste collection infrastructure was based around not recycling, and I was too young to take them to the recycling centre myself, I ended up throwing them into the bin and I forgot about the issues and importance of recycling. In 2011, at the end of Bike Week, there will be the same realisation and people will get back into their cars and forget about cycling for another year, because approaches based extensively on conscious, elective behavioural change are inherently very limited in their ability to bring about significant long-term results.