Ellieb wrote:So. What has been the effect of the growth in Cycling infrastructure on cycling KSI stats? That, surely is the important question.
It depends on the type of infrastructure. For example the injury rate at junctions (which is where accidents mainly occur) can be up to 12 times higher on a "wrong way" cycle track i.e. The direction on a two way track that goes against the flow of the adjacent motor lane. (See figure from a Swedish study of the relative accident risks at a junction)
See the figure, but don't you dare look at the rather difficult-to-obtain 1987 study from Lund University which doesn't really support this blanket (ab)use of those figures against all infrastructure.
The most thorough and detailed "before/after" study done around the construction of a new cycle track and lane in Copenhagen found
"The safety effects of bicycle tracks in urban areas are an increase of about 10 percent in both crashes and injuries. The safety effects of bicycle lanes in urban areas are an increase of 5 percent in crashes and 15 percent in injuries. Bicyclists’ safety has worsened on roads, where bicycle facilities have been implemented."
Yes, let's quote a bit and not link to the study http://trafitec.dk/sites/default/files/ ... 0lanes.pdf
which shows that those percentages are against the researcher's expectations (an approach that even the author calls a "second-best methodology" and I feel that second is ranking it a bit high) and not the pre-implementation figures.
Interestingly a significant part of that increase was found to be from the increased number of cars turning across the cycle facility to look for side street parking because parking was reduced on the road to accommodate the facility
That is interesting but just goes to show what many activists have always said, that it's all connected. There's often no good reason to reduce parking when building a cycle facility: that's a choice of the highway designers and it's unfair to scapegoat the cycleway for it.
The London experience has not been good either. Bothe the Bloomsbury and Royal College Street segregated cycle facilities have suffered excessive accident rates at junctions.
Prove it. Last time I remember that claim being made in viewtopic.php?p=864724#p864724
there seemed to be no evidence for RCS.
But overall safety should not really be a consideration, although it's usually the reason given for why they are needed, as either way it's still very safe.
I agree that overall safety shouldn't be a reason for them and I don't think it is by most people who engage their brain. TfL proposes its "superhighways" (I agree, they're misnamed, but marketing is part of the battle) primarily to "provide a clear and convenient route for cyclists" along with a raft of secondary reasons such as "to encourage the large numbers of people who would like to cycle, but currently feel unable to" and to "draw cyclists away from other routes in central London which are less suitable for them".
Anyway, I would like to thank TonyR for the continual exhortations that infrastructure is necessary but not sufficient
and again invite anyone to show anywhere that has a modal shift to cycling without cycling-friendly infrastructure of some sort.