What are low traffic neighbourhoods and modal filters?June 13, 2020 0 COMMENTS
A low traffic neighbourhood (LTN) is a very simple idea: it’s protecting a group of residential streets from through traffic (rat runs). It works best for an area up to 1km2 because it is walkable, so no longer than a 15 minutes walk. LTNs are usually bordered by main roads or natural lines (river, trainlines, etc…).
This is achieved with a combination of modal filters (planters, bollards, alternated one way streets, bus gates – where buses are the only motor vehicles allowed -, school streets) placed in several locations within the area. This prevents motor traffic from using residential streets to bypass the main road near by. This ‘short cut’ phenomenon has worsened recently because of phone apps such as Waze which identify, in real time, quieter and congestion-free areas and tell drivers to go there instead of staying on the main road.
With quieter streets, local residents are safer to walk or cycle around their neighbourhood and people living there, as well as their visitors, can still access every address by car. Access is enabled by going around, instead of through.
There are some misconceptions about low traffic neighbourhoods, here is a myth buster from A Guide to Low Traffic Neighbourhoods by Rosehill Highways, London Living Streets and London Cycling CampaignMyth-Buster-LTNs
A study of emergency services response times was published following the implementation of low traffic neighbourhoods in Waltham Forest and evidence shows that response times have actually improved not surprisingly since this is a measure that is effective at reducing traffic.
Low traffic neighbourhoods are highly effective in reducing pollution, road danger and cutting congestion. By also enabling active travel, LTNs lead to noticeable improvements to residents’ health. Businesses and retailers, within the neighbourhood, also benefit as it is well evidenced that shoppers visiting on foot, cycling or by public transport spend and average of 30%-40% more than those coming by cars.
With regards to fears over traffic displacement, this study by Professor Rachel Aldred shows that traffic does not behave like water and that drivers will adapt by either changing their habits (for instance, instead of going to a shopping mall, people may start using their local shops more, therefore not needing the car) or swapping transport modes. This is known as traffic evaporation and it usually leads to a 15% reduction in motor traffic.
Sustrans have just produced an An introductory guide to low-traffic neighbourhood design to help communities with improving their own neighbourhoods. This guide contains practical advice from making the case for a LTN to a method on prioritisation.
Sylvia is the current Brent Cycling Campaign Coordinator. She is a Cricklewood resident and a cargobike mum of two.