Motorways through the West Midlands could be covered by tunnels or canopies to protect communities from dangerous levels of pollution, Highways England has announced.

The agency responsible for Britian’s motorway network has been monitoring the high levels of pollution on the M6, M5 and M42 in the West Midlands, as well as several other UK hotspots, since last year.

And now in its new Air Quality Strategy has revealed it is talking to Dutch roads officials who have been testing pollution catching canopies there.

It also trialled a six metre high barrier alongside a 100m stretch of the M62 in Manchester designed to absorb dangerous car and lorry emissions.

The strategy states that Highways England is “investigating if we can reduce the costs to construct a canopy, which is a tunnel-like structure designed to prevent vehicle emissions reaching our neighbours”.

Heavy traffic on the M6

Highways England said it would consider implementing such barriers across its network of England’s motorways and major A-roads.

Poor air quality is linked to 1,500 premature deaths through respiratory disease a year in the West Midlands, 40,000 across the country.

The Government, under threat of legal action, has been warned to reduce the problem by 2021 - and last week it unveiled plans including a ban diesel and petrol cars by 2040.

The Government also handed Highways England £100 million to develop pollution busting measures. Plans include encouraging electric car use by putting a charging point every 20 miles on the motorway network.

They also plan to work with HGV operators, by far the biggest polluters, to make it easy for them convert their fleets to lower emission fuels.

West Midlands is one the UK's pollution hotspots

A Highways England spokesman said: “The best solution to accommodating the extra traffic on our roads without negatively impacting on air quality is cleaner low-emission vehicles.

“In the meantime, we are investing £100 million to test new ideas including less-polluting fuels and road barriers which can absorb harmful emissions.”

The RAC has issued a note of caution over the canopies warning of the impact of the trapped pollution on the people in vehicles.

Spokesman Nick Lyes said: “The solution should be about reducing levels of pollution by accelerating the transition to ultra-low and zero emission vehicles and encouraging better traffic flow through variable speed limits - something Highways England has started doing on smart motorways.”