Highway Safety
Report Reveals Trouble With UK's Smart Motorways
The U.K.'s all-lane running smart motorways eliminated hard shoulders to add live traffic lanes, with emergency shoulders spaced about 1.2 miles apart.
Photo courtesy National Highways
A year after the U.K. government halted the expansion of so-called "smart motorways," pressure is growing to reintroduce emergency hard shoulders on nearly 200 miles of national highways. A new BBC probe identified significant failings in the technology designed to alert drivers to blockages in live traffic lanes.
To increase capacity without building new highways, the U.K. government in the last decade has converted the hard shoulders on around 260 miles of motorways into live lanes.
Around 80% of these are all-lane running (ALR) with no hard shoulders. On the rest, "dynamic" hard shoulders are activated only during periods of congestion. In ALRs, emergency areas are spaced generally at 1.2-mile intervals. Without hard shoulders, these smart routes rely on technology to detect and warn of stalled vehicles.
But according to freedom of information data secured by the BBC's Panorama program, there were 392 occasions between June 2022 and February 2024 when the technology lost power, sometimes for long periods. In the six months ending in February, there was a recorded outage almost every day, according to Panorama.
While National Highways' data shows smart motorway to be safer than conventional ones, officials concede the system creates public unease. According to a survey last year by the car breakdown and insurance service company, RAC Ltd., 69% of respondents wanted the hard shoulder to be reinstated on existing ALRs.
Map courtesy National Highways"While heralded as a cost-effective way of increasing capacity ... a colossal amount of public money has since gone into trying to make them safer," says RAC's head of policy Simon Williams.
Since the government halted new smart motorways last April, the highways agency has been investing more than $1.1 billion on improving technology and increasing the number of emergency areas on the network.
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The government "should either convert existing all-lane-running smart motorways to ‘dynamic’ ones ... or repaint the white line and reintroduce a permanent hard shoulder," adds Williams.
But while parliament’s Transport Select Committee called for a halt to ALRs early in the program eight years ago, the lawmakers do not support wholesale reinstatement of hard shoulders. In their most recent report in 2022, the lawmakers endorsed the government’s safety upgrade work.
