A large study of ‘low-traffic neighbourhoods’ in London shows that these LTNs reduce motorized traffic on streets within the schemes but, contrary to some claims that LTNs increase congestion on adjacent main roads, data analysis did not find an increase in motorized traffic. on “border” roads.
The study found that average decreases in motor traffic on highways within LTNs are nearly ten times greater than average increases in motor traffic on bordering highways, suggesting that LTNs are creating a substantial overall reduction in traffic. traffic.
Conducted by the University of Westminster’s Active Travel Academy, the study will be published in a peer-reviewed journal later this year.
The preliminary findings of the study were published in a report published on January 19 by the climate charity Possible, which also commissioned the research.
Data analysis found that the average average decrease in motor traffic on highways within LTNs was nearly ten times greater than the average increases in motor traffic on bordering highways.
In London, the average percentage reduction in traffic on streets within LTNs was 46.9%. This has resulted in more streets experiencing fewer than 1,000 motorized vehicles passing through them daily, implying that there may be a qualitative change in the local environment that has meant an increase in walking and cycling.
The study also analyzed the impact on border roads surrounding the LTNs. Overall, 47% of the border roads surrounding the LTNs experienced a decrease in traffic and 53% experienced an increase. Average motor traffic counts showed that traffic changed relatively little on border roads, with an average average increase of only 82 motor vehicles per day, an increase of less than 1% on the average average of 11,000 motor vehicles passing through the border roads on a typical day. .
Acknowledging this slight increase, the report authors note the importance of substantial variations, both in increases and decreases in traffic on bordering roads and between individual LTN schemes.
These variations, the report notes, are likely not caused by LTN alone, but could be caused by other contextual factors, such as major local works or broader underlying trends.
For example, the report notes that in Newham, increases in motor traffic may be due to Olympic legacy development, particularly increased motor traffic on border roads. This leads the report to conclude that with the installation of an LTN, an increase or decrease in motorized traffic on the bordering roads should not be expected.
The study’s lead author, Asa Thomas, Ph.D. Active Travel Academy researcher, said:
“This study finds that most streets within the LTN see reductions in most traffic, improving the walking and biking experience. Two-thirds of these now have vehicle flows below 1,000 vehicles per day, a rough threshold for a quiet, pedestrian-friendly street, compared to just two-fifths before. In addition, there are few indications of a systematic displacement of this traffic towards the bordering roads”.
Report co-author Professor Rachel Aldred, Director of the Active Travel Academy, added:
“Research indicates that there has been a general evaporation of traffic due to these schemes, as the average average reduction in motorized traffic on internal roads is about ten times greater than the average average increase on border roads, adjusting for traffic trends. bottom. This suggests that LTNs not only have substantial benefits within their boundaries, but may also contribute to broader traffic reduction goals.”
The report emphasizes the need to consider that border roads are still very likely to be contaminated, unsafe, or difficult to cross or bike. The removal of LTN is unlikely to alleviate these problems, said a statement from Possible, so it is “vital that local authorities consider measures such as expansion of low emission zones, road user charging, increase in the number of bus lanes and the provision of public transport, urban greenery, widening of sidewalks and [installing] protected bike lanes.”
Possible is also calling on local authorities to use the report’s findings to introduce more LTN and challenge what the organization says is misinformation about direct impacts on bordering roads.
They also call for more measures to address traffic on these border roads.
Hirra Khan Adeogun from Possible said:
“This report shows that low-traffic neighborhoods have a verifiable positive impact on the people who live on these streets. But more importantly, it shows that they don’t have a constant impact on bordering roads. In a climate crisis, we need our policymakers to make bold, data-driven decisions; this report gives you that information. What we need now is action to reduce traffic, make our cities happier and healthier, and directly address the climate crisis.”
On social media, LTN critics describe border roads as “sacrificial” because they claim LTNs push motorized traffic from smaller residential streets onto surrounding main roads, increasing congestion on these roads and creating more pollution. , which affects the residents who live in these. main roads
“These border roads are also where most of the active travel occurs and where people wait for buses, shop and work,” said Paul Lomax, an amateur traffic data expert who late last year caught errors in the statistics. Department of Transportation nationals that resulted in a correction
“There are eight times as many motor vehicle injuries on these sacrificed and often highly residential highways as there are on highways now within the LTNs,” added Lomax, a vocal critic of the LTNs.
Commenting on the study’s preprint, Lomax said: “While the report acknowledges that LTNs can increase traffic on bordering roads, this is dismissed as a ‘small change.’ Given that the border roads have ten times more traffic than the internal roads studied, this is not surprising: 100% displacement would result in similar percentage changes. This highlights the concern that these schemes improve the less problematic roads to the detriment of the roads that need help the most.”
Speaking to me over Zoom, Possible’s Adeogun criticized the description of border roads as “sacrifice.”
“Why aren’t they considered sacrifices when 11,000 cars pass them on average every day? Isn’t that already a sacrifice?
He added that the introduction of LTN is just one of the measures that local authorities must carry out to combat climate change.
“LTNs are not the only solution to all of our congestion problems, but they are a piece of the puzzle. We also need smart charging for road users, and we also need to invest in public transport and have protected cycle lanes.”
Lomax is open to traffic reduction measures, but does not believe that any studies have yet shown that LTNs reduce congestion overall.
“This latest report robustly analyzed fundamentally flawed data collected by councils that marked their own homework. Of the 96 schemes identified, only 46 are studied due to lack of data, which could be the result of survival bias with failed schemes being quickly withdrawn. Councils selected the locations to be monitored, often omitting key alternate routes for displaced traffic from their monitoring; It’s not just bordering roads that are affected. And because pneumatic tube traffic counters do not count traffic below 10 km/h as standard, due to accuracy issues, any increase in congestion could mask an increase in traffic flow or even show itself. as a reduction.
Critics often label the University of Westminster’s Active Travel Academy as biased, a claim Adeogun disputes.
“Academic scholars are transportation experts and their work is peer-reviewed in reputable journals. Questioning whether experts should specialize is like saying that someone who wants to beat the coronavirus should not be doing research on the coronavirus.”
The academy report mentions “potential drawbacks” to LTNs, including “possible impacts on travel time for those who have no choice but to drive, such as some disabled LTN residents, whose trips may become longer due to They have to leave their neighborhood via a different route.”
In our Zoom call, Adeogun from Possible said that LTNs could also benefit some people with disabilities:
“There are lots of disabled people trapped in our car-dominated landscape. People with disabilities are not homogeneous; They don’t have the same needs. Yes, for some disabled people cars help their mobility, but other disabled people cycle or benefit from wider curb space for wheelchairs. We must restructure our cities to ensure they work for everyone, including people with disabilities.”
Adeogun added: “To people who say that the main roads are sacrificial roads, I would say yes, they are heavily polluted, so please join us and help and help alleviate the problem.”