What is a smart motorway, amid claims that tech leaves drivers at risk?

 (Jonathan Brady / PA)
(Jonathan Brady / PA)

A recent BBC Panorama investigation has found that the equipment supporting England's smart highway network frequently malfunctions.

According to data made available by the programme in response to Freedom of Information requests, there were 397 instances of smart highway power outages between June 2022 and February 2024, making it challenging to identify when a car has broken down.

Of these, 174 were power outages that occurred in the six months preceding February 2024 – or about one every day.

The agency in charge of National Highways has denied that its motorways are unsafe.

The UK still has many kilometres of installed smart motorways.

But what is a smart motorway and are they dangerous?

What is a smart motorway?

A smart highway is a segment of a motorway that, in very congested sections, uses traffic-management techniques to boost capacity and lessen congestion.These techniques include setting variable speed limits to regulate traffic flow and using the hard shoulder as a running lane.By minimising the need to create extra lanes, Highways England (formerly the Highways Agency) developed smart motorways to manage traffic in a way that minimises the impact on the environment, construction costs, and construction time.

There are three types of smart motorways: all-lane running, dynamic hard shoulder, and controlled motorway.

There are 193 miles of "all-lane-running" motorways, which means that an additional lane has been created by permanently removing the hard shoulder.

Are smart motorways dangerous?

They lack a hard shoulder, therefore, many people believe that smart motorways are riskier than traditional motorways.

The most recent data from National Highways indicates that you have a three-times higher chance of dying or suffering severe injuries if you break down on a smart motorway without a hard shoulder than if it has one.

Due to financial and safety issues, the Government declared last year that it was stopping the construction of smart motorways.It is not planning to reinstate the hard shoulder, but is spending £900m on technology to make the current network safer.

The Government also pledged in 2020 to construct more emergency refuges, or safety laybys that drivers can use in an emergency, as part of its upgrading strategy.

Just 13 of the 150 that were expected to be constructed by the next year have been finished, though.

National Highways said an additional 34 refuges are under construction.