Source: CROW-Fietsberaad, Verkeerskunde

The Netherlands has a system in place which categorises the width of cycle paths, from sufficient width in relation to traffic volume, through to substandard and too narrow. Recent analysis has explored national cycling volume data and accident data, drawing parallels between cycle path width and numbers of cycling accidents.

A notable statistic is that over 80% of seriously injured cyclists are injured in accidents that do not involve a motor vehicle, and that single-bicycle accidents are particularly common. Traffic engineers’ platform Verkeerskunde highlights that this is precisely the type of accident in which infrastructure – and specifically cycle path width – may play an important role.

CROW-Fietsberaad, the Dutch government’s knowledge centre for cycling policy, and consultancy firm DTV investigated the occurrence of accidents in conjunction with data on cycling volume and the system of cycle path width labelling. The labels range from A and B, representing sufficient path width in relation to cycling volume, usage and the mix of cyclists, through to C to F, which indicate widths from substandard to severely too narrow.

Data on the location of single-bicycle accidents comes from the Database of Registered Accidents in the Netherlands (BRON). To account for the fact that the database does not include many accidents which have not been officially registered by the police, the data has been supplemented with details from a panel survey of self-reported bicycle accidents.

Data on cycling volume and width labels was taken from the National Road Traffic Safety Data Portal, which provides figures on both peak-hour and raw 24-hour cyclist volumes. The analysis included all inner-city segregated cycle paths longer than 10 metres.

The study demonstrates that cycle paths which are too narrow for the volume of traffic experience significantly more accidents. The combination of data sources used in the study represents an important step in developing bicycle safety policy, with the width labels proving useful as Safety Performance Indicators (SPIs) and enabling the identification of high-risk locations. This gives road authorities the necessary information for effectively determining where the widening or modification of cycle paths will yield the greatest safety gains.