Can low traffic neighbourhoods reduce overall car use?

Acknowledging this small increase, the report goes on to note the importance of the substantial variations, in regard to both increases and decreases in traffic on boundary roads, between individual LTN schemes. These variations, the report points out, are not likely to be primarily caused by LTNs but could, instead, be caused by other contextual factors such as major local works or wider background trends. 

For example, the report notes that in Newham increases in motor traffic may well be due to Olympic legacy-related development, particularly increasing motor traffic on boundary roads. This leads the report to conclude that with the installation of an LTN, there should be no expectation of an increase or decrease in motor traffic on boundary roads.

Low emission zones

The report emphasises the need to consider that boundary roads are still highly likely to still be polluted, unsafe, or difficult to cross or cycle on. Removing LTNs is unlikely to alleviate these issues so it is vital for local authorities to consider other measures that could. For instance, expanding low emission zones, road user charging, increasing the number of bus lanes and public transport provision, urban greenery, widening pavements, and protected cycle lanes could all make a contribution.

Possible is calling on local authorities to use the report’s findings to introduce more LTNs and to challenge misinformation about the direct impacts on boundary roads. They are also calling for further measures to address traffic on these boundary roads.

“This suggests that not only do LTNs have substantial benefits inside their boundaries, but they can also contribute to wider traffic reduction goals”

“This study finds that most streets within LTNs see reductions in most traffic, improving the experience of walking and cycling,” said Asa Thomas, PhD researcher at the Active Travel Academy, University of Westminster and lead author of the study. “Two-thirds of these now have vehicle flows below 1,000 vehicles a day, a rough threshold for a quiet pedestrian friendly street, compared to only two-fifths before. What’s more, there is little indication of systematic displacement of this traffic to boundary roads."

Professor Rachel Aldred, director of the Active Travel Academy at the University of Westminster and co-author of the study, added: “The research indicates there has been overall ‘traffic evaporation’ as a result of these schemes, as the mean average reduction in motor traffic on internal roads is around 10 times higher than the mean average increase on boundary roads, adjusting for background trends.

“This suggests that not only do LTNs have substantial benefits inside their boundaries, but they can also contribute to wider traffic reduction goals.”

Possible is a UK-based charity that brings people together to take positive, practical action on climate change. The Active Travel Academy is a research centre based within Westminster University’s School of Architecture and Cities.