Travel Counts

If people feel it is safe, they are more likely to walk or cycle. Pedestrian and cyclist count data offers an objective alternative to the subjective evaluations of field surveys.

We analysed pedestrian and cyclist count data from automated counters in a US city. To isolate the effect of light from other parameters (purpose and destination) we compared pedestrian/cyclist numbers for a certain hour in the few days before and after daylight savings clock change. This hour tended to dark before clock change and to light after clock change (and vice versa) and was compared with control hours (permanently light or dark before and after clock change) using an odds ratio.

The results show significantly fewer people tend to walk or cyclwhen it is dark.

Uttley J, Fotios S. Using the daylight savings clock change to show ambient light conditions significantly influence active travel. Journal of Environmental Psychology 2017; 53: 1-10

To validate the findings, the travel count data were analysed using an alternative method of analysis which considered pedestrian and cyclist counts across the whole year rather than just those days near to the clock change.

These results also show that significantly fewer people tend to walk or cycle when it is dark.

Fotios S, Uttley J, Fox S. A whole-year approach showing that ambient light level influences walking and cycling. Lighting Research and Technology 2019; 51(1): 55-64.

In this study the travel count method was extended to investigate the impact on light level on cycling numbers. This was done by plotting the ambient light level odds ratio for each location against a measure of light level at that location.

Uttley J, Fotios S, Lovelace R. Road lighting density and brightness linked with increased cycling rates after dark. PlosONE 2020; 15(5): e0233105.

If the numbers of cyclists and pedestrians reduces after dark, what are they doing instead? There could be a change in travel mode (e.g. to drive rather walk) or there could be a decision to not travel at all. In this paper we investigated the change in numbers of motorised vehicles after dark alongside those of pedestrians and cyclists. The investigation again found a reduction in walking and cycling, but did not reveal any impact on the numbers of motorised vehicles.

Fotios S, Robbins CJ. Effect of ambient light on the numbers of motorized vehicles, cyclists and pedestrians. Transportation Researcjournals.sagepub.com/doi/10.1177/03611981211044469 h Record 2022; 2676(2): 593-605.