Motorway speed limit restored to 70mph

THE 60MPH speed restrictions on the M1 and M6 will be removed after National Highways admitted that air pollution will “ultimately be solved at the tailpipe”.

Since 2021, drivers have been forced to slow down at the M1 at Rotherham and the M6 at Witton, in the Midlands, in a bid to establish if driving more slowly helps reduce emissions.

The restrictions were only supposed to last between 12 and 15 months with National Highways promising that data showing if the schemes were working would be available last spring.

Yesterday, the body said the sections would return to the national speed limit of 70mph, after pollution had fallen in the area, but could not say whether this was because of the trials or due to more electric and hybrid cars on the road.

Angela Halliwell, National Highways’ head of Carbon and Air Quality Group, said: “There is an overall trend that air quality is improving across our network. Removing 60mph speed limits from sections of the M1 and M6 where air quality has improved is a positive step. Ultimately, air quality will be solved ‘at the tailpipe’ by vehicle manufacturers and changes in vehicle use.”

A new report released by National Highways this week shows that nitrogen dioxide levels fell in the Rotherham speed restriction zone from 39 micrograms per square metre (g/m3) to 35g/m3.

The analysis showed there was no real change in average speeds following the introduction of the 60mph speed limit on the M6, as average speeds were already close to 60mph. Nitrogen dioxide levels were at 32g/m3.

National Highways said it was “highly unlikely” that the pollution limits would exceed the legal limit if restrictions were removed, but could not say how it had come to that conclusion.

It said it would continue to monitor both locations and was continuing to assess whether the scheme had actually been successful.

However, the report also shows that some areas with speed restrictions have seen pollution levels increase, including the trial site at the M602 at Eccles, and the M4 at Hillingdon, while nitrogen dioxide levels have remained the same at the M5 at Oldbury.

Motoring groups have previously warned that speed restrictions could increase congestion and may make pollution worse.

The AA has argued that the most polluting vehicles, such as large lorries, were already limited to 60mph anyway, while police forces often allowed 10 per cent plus 2mph leeway to the speed limit, meaning drivers could still be driving near 70mph during the trials.

‘As no results have been published, one can only assume the evidence does not support the reductions’

An AA spokesman said: “Removing the 60mph zones will allow traffic to move at speeds for which the roads were designed, thus improving journey times and the efficiency of the network. Where there are speed limits with no obvious reason, you lose the understanding and support of the driving public – eventually leading to anger.”

National Highways said that air quality was influenced by multiple factors and that building work near the speed restriction areas may have been a factor.

Earlier this week, National Highways refused an FoI request by asking to see the latest modelling and analysis for the 60mph zones, claiming that the experts need a “safe space” to carry out their work.

Although National Highways accepted the information was within the public interest, they said: “While this issue is live, a safe space is needed to think, continue with the ongoing analysis, and make decisions about the information.

“At this time, releasing part of the analysis may lead to a misunderstanding of the facts and impacts. This would not enable a reasoned and informed discussion to be held, either with internal stakeholders nor members of the public as to whether speed limits introduced for air quality should or should not be retained.”

But motoring groups said if there was no modelling or analysis to show whether the schemes were working then they should all be scrapped.

Bob Bull, of the Alliance of British Drivers, said: “The practice of 50 and 60 mph limits on motorways on air pollution grounds appears to be worthless but causes frustration and bunching.

“As no results have been published, despite promises that they would be available a year ago, one can only assume the evidence does not support the arbitrary reductions.”

The lowering of the speed limit was introduced based on modelling that claimed it would significantly reduce the annual mean nitrogen dioxide concentrations in the affected zones.

National Highways drops M1 and M6 60mph restrictions after pollution study draws a blank