Evaluating the impact of low traffic neighbourhoods in areas with low car ownership: A natural experimental evaluation
Journal of transport & health 2023 ; 101658: .
Xiao C, Sinclair N, Saunders L, Panter J
DOI : 10.1016/j.jth.2023.101658
URL : https://www.doi.org/10.1016/j.jth.2023.101658
Abstract
Background
Improving the environment, including the streetscape, can enable walking and cycling, which impacts health. The aim of this study was to measure the impact of modal filters implemented as part of Low Traffic Neighbourhoods (LTNs) in Southwark, a borough with low car ownership located in Inner London, on driving, walking, and cycling levels.
Methodology
Three neighbourhoods (Brunswick Park, North Peckham, East Faraday) introduced modal filters which restricted motorised traffic through-movement but not walking and cycling. Intervention areas were matched to control neighbourhoods with no street changes. Daily traffic, walking, and cycling counts and traffic speeds were collected using automatic counters and video monitors in all neighbourhoods at baseline and one year. In each neighbourhood we delineated ‘project’ and ‘boundary’ streets to capture potential displacement of traffic. We used a difference-in-differences analysis to estimate the effects of the LTNs by calculating the change in travel behaviours in intervention areas relative to control areas.
Results
Daily traffic counts decreased on ‘project’ streets in the intervention areas relative to controls by 860 (95% CI 409, 1312) in Brunswick Park, representing a 56% decrease (IRR 0.44, 95% CI 0.28, 0.68), and by 937 counts (95% CI 328, 1546), representing a 61% decrease (IRR 0.39, 95% CI 0.26, 0.71) in North Peckham. Traffic volumes did not significantly change in East Faraday. Across all three intervention project areas, traffic speeds decreased. Traffic levels remained unchanged on ‘boundary’ streets, with the exception of Brunswick Park, where there was an uplift in traffic levels during weekdays and peak hours. In general, there were no significant changes in daily walking and cycling counts.
Discussion
Findings from this study demonstrate that modal filters can reduce traffic speeds and volumes on ‘project’ streets. Although these measures can offer a safer, less polluted, and more inviting environment for pedestrians and cyclists, areas with low car ownership may need further initiatives to boost walking and cycling.
Lay Summary
The study was conducted in Southwark, London, an area with low car ownership. The goal of the study was to see how modal filters, which are part of Low Traffic Neighbourhoods (LTNs), affected driving, walking, and cycling. Three neighbourhoods (Brunswick Park, North Peckham, and East Faraday) implemented modal filters, which restricted motorized traffic from passing through but not walking or cycling. The intervention areas were compared to control areas that did not have any street changes. Daily traffic counts, walking and cycling counts, and traffic speeds were collected using automatic counters and video monitors in all neighbourhoods at the beginning of the study and one year later. The findings of the study show that modal filters can reduce traffic speeds and volumes on project streets. In Brunswick Park, there was a 56% decrease in traffic counts, and in North Peckham, there was a 61% decrease. Traffic volumes did not change significantly in East Faraday. Traffic levels remained unchanged on boundary streets, except for Brunswick Park, where there was an increase in traffic levels during weekdays and peak hours. There were no significant changes in daily walking and cycling counts. The study's findings suggest that modal filters can be an effective way to reduce traffic and create a safer and more inviting environment for pedestrians and cyclists. However, more initiatives may be needed in areas with low car ownership to boost walking and cycling.