One of the presentations at last month’s London Cycling Campaign Seminar Series was from Ian Garrard of Brunel University. Ian was one of the authors – along with Ian Walker and Felicity Jowitt – of a paper examining the influence of a cyclist’s appearance on overtaking distance. The paper is freely available here, and well worth a read.
One of the standout findings is that 1-2% of the thousands of overtakes measured came within 50cm of the ‘trial subject’ (Ian himself) – and this on roads that included 60mph limits – and that this was consistently the case, regardless of the clothes he was wearing. It seems that a minority of drivers just don’t care, and will continue not to care, regardless of who they are overtaking, what they look like, and what they are wearing.
But I was most interested by this slide from Ian’s presentation.
Compared to 1979, British drivers – on average – now get 34% closer to people cycling while overtaking. (This is in just one region – the region in which the study was carried out – but likely to be reflected across Britain).
What’s the explanation? Are British drivers of today that much worse than those of 1979? That seems unlikely – there’s no standout reason why British drivers of the 1970s would have been trained any better, or behaved any better.
Ian Garrard’s (speculative) hypothesis is that motor traffic volume has substantially increased since 1979, which raises the risk of being on the receiving end of a close overtake. With lower traffic levels, it’s much easier to overtake correctly, as there’s less chance you will encounter a cyclist while there is oncoming traffic. With higher traffic levels, the ‘windows’ of an empty oncoming lane are more scarce, and the option of just ‘squeezing through’, instead of waiting patiently, becomes increasingly tempting.
The hypothesis is plausible, and worth examining in more detail – doubtless the closer overtakes would correspond to the busier roads, with the wider overtakes occurring on the quieter ones. I’ve observed – anecdotally – how easy it is form a misleading impression of continental drivers, based on the fact that British people cycling in Europe will generally be doing so in low traffic areas, at off-peak times – on holiday.
This issue of overtaking distance cropped up again, around about the same time as that LCC seminar, in a musing from Carlton Reid that Dutch drivers might give more overtaking distance – suggesting that Ian Walker use (or lend someone!) his proximity test in that country to find out whether that is true. My immediate instinct is that such a test would be fairly meaningless. For a start, on roads that carry significant volumes of motor traffic – above about 3-4000 PCU/day – it is almost always impossible for Dutch drivers to overtake closely to people cycling.
Roads that carry high volumes of motor traffic, or where motor traffic is travelling at higher speeds, form part of a system where cyclists are catered for separately. They don’t have to share these roads, as a matter of design principle. And they won’t be overtaken closely, because it’s just impossible.
Of course, the remaining parts of the Dutch road network are places where Dutch cyclists will share with drivers, but these parts of the network are places where there is very little motor traffic; almost always below that 3-4000 PCU/day threshold. And so these are places where (Dutch) drivers will find it much easier to overtake properly – for the reasons discussed above.
These roads and streets will, for the most part, serve access purposes only; to residential areas in towns and cities…
or to link up properties in rural areas.
These rural roads will only be used by local motor traffic, because faster roads have been provided for drivers, and/or they are restricted as through routes. Consequently, there will be very little oncoming motor traffic, and very little opportunity to do crappy overtakes. Indeed, a basic rationale of Dutch sustainable safety is to remove the opportunity to perform a crappy overtake entirely.
The consequences of driver error, and driver stupidity, are slowly being designed out of Dutch roads and streets. So, really, measuring driver overtaking distance under this kind of system – sadly so very different to the prevailing conditions on British roads – would tell you very little about Dutch driver behaviour. It would be almost equivalent to measuring the distance with which British drivers overtake pedestrians.
Note – the one way in which a legitimate comparison might be made is to examine overtakes on two equivalent segments of road, in Britain and the Netherlands, of the same approximate width, carrying the same approximate volume of motor traffic.