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Smart motorways: what are they good for?

Image credit: Brett Critchley | Dreamstime

The Department for Transport (DfT) has recently proposed plans to ensure the safety of ‘smart motorways’ – but will they be smart enough to prevent further loss of life on our roads?

A desperate 999 call makes for harrowing listening – it’s from a father whose family car has broken down in a live lane of traffic on the M6 near Knutsford just before a lorry smashes into the back of them. “Oh shit” are the last words the emergency operative hears before the gut-wrenching sound of crunching metal.

Amazingly, the parents and children all survived – they believe a boot stacked full of Christmas presents softened the impact.

This incident happened in 2017 on a stretch of motorway which didn’t have a hard shoulder because of road works – it was being converted into a smart motorway at the time.

This year, a mother, whose eight-year-old son was killed in 2018 after a truck piled into his grandfather’s car which was marooned on the live lane hard shoulder on the M6, has criticised the government’s handling of smart motorways. Why, she asked, was a scheme rolled out before correct technology to protect motorists and driver awareness was in place? In February, a woman and her father-in-law were killed when a lorry smashed into their car on the M25 in Essex. They were sheltering behind a safety barrier, but a hard shoulder or refuge area would have saved them, the judge ruled – although the lorry driver was also convicted of careless driving.

As outrage grows against smart motorways – in which the hard shoulder is turned into a live lane – work is at a standstill and the government awaited results of a delayed review (now published) of a nationwide programme to convert hundreds of miles of traditional motorway. Works on the M27 and elsewhere around the country are standing idle, but smart motorways on the M1, M4, M6 and M62 remain running.

But if all lane running motorways – which sees the hard shoulder permanently converted into a live lane – were implemented with adequate technology and crucially more safety areas, would they be as safe as conventional motorways?

Opponents say the concept is flawed, with cars forced to swerve around broken down vehicles. But motorist groups agree the hard shoulder isn’t a safe place either. One in 12 fatalities occur on a hard shoulder says Highways England, and 90 per cent of stops are unnecessary. A permanent hard shoulder increases danger – people stop illegally for toilet breaks, drive along it when they shouldn’t or drift into it when their concentration lapses. Highways England argues removing the hard shoulder removes these risks.

“Motorways are the safest type of roads,” says transport specialist Christian Wolmar, who points to the lack of a hard shoulder on A roads and dual carriageways. “So anything that increases capacity – and stops drivers taking rat runs through cities or even A roads means, in theory, they are safer. But unless you have like-for-like statistics, you can’t compare safety.”

There’s no doubt hard shoulders are scary places, says Peter Eccleson, managing director of Smart Video & Sensing. But he recently crawled to a halt on an A road, and admits the sight of a lorry rushing up behind with no hard shoulder was terrifying.

“Smart motorways have done what they set out to do which is increase capacity,” he says. “But it’s widely agreed they don’t have enough emergency refuge areas.” And that, say drivers’ groups and campaigners, is a scandal.

Smart motorways were first floated as a concept in 2005 – the hard shoulder would convert into a live lane at busy stretches, with variable speed limits displayed on overhead gantries. Congestion costs an estimated £2bn a year – a quarter of that from traffic incidents, says Highways England, the government company charged with running the country’s roads. They allow an increase in road capacity for less money, and without breaching the existing footprint and building on new land. “They’re just as safe – often safer,” says the agency on its website.

Variable speed limits ease traffic flow. If a car breaks down, a mix of technology - radars only on the M25, CCTV, vehicle detection technology and the drivers themselves - can raise the alarm. Motorists are alerted via a red cross above a lane signalling its closure.

Early tests were successful, says Highways England – smart motorways were first trialled on part of the M42 in 2006, with research showing accidents causing injury more than halved, and journey reliability increased. But when they were rolled out more widely, misgivings grew.

Scanning radar which detects when vehicles have stopped has only been installed on two four-lane stretches of the M25, and is currently being retrofitted on a smart stretch of the M3. But it hasn’t been installed anywhere else. And – shamefully, say campaigners - emergency areas are far further apart than they should be.

In the last five years, 38 people have been killed on smart motorways, some victims struck by moving traffic, a BBC Panorama investigation found. The same programme also revealed a 20-fold increase in near-miss incidents on one stretch of the M25. Five people have been killed on two stretches of the M1 in the last year, says the AA. “We feel they could have been avoided if there had been more emergency refuge areas, though Highways England doesn’t agree,” says Jack Cousens, head of roads policy at the AA, which is calling for numbers of safety areas to be doubled. 

Currently, these refuges are at a maximum 1.5 miles apart – and on average 1.25 miles across the all lanes running network, says Highways England, which means at 60 miles an hour, a driver would pass one every 75 seconds. But the AA calls for spacing of just three-quarters of a mile apart and says the current distance was decided by Highways England in 2012 with no public consultation. This spacing is also much wider than on the original M42 trial, where refuges were 500 to 800m apart, with a risk rate of 32 per cent, whereas 1.5 miles has an estimated risk of 85 per cent (against a benchmark 100 per cent risk of a conventional motorway). In 2018, Highways England said they would reduce this to a mile on new stretches, though this could now change.

“It’s the same theory that Disney theme parks had with litter bins,” says Cousens. “If you can see one you will put your rubbish in it rather than drop it. If you spot a refuge, you will limp into it, but if not, you will panic and stop where you are.” Earlier this year (1 February) The Times reported that Highways England – the Highways Agency as was – even considered having no roadside refuges on stretches of smart motorways, but decided against it partly due to concerns about its own reputation.

And the AA has discovered that breakdowns over approximately two years (August 2017 to October 2019) on a 13-mile smart section of the M3 between Junction 2 – 4a has caused some 945 hours of traffic jams – and more than 2,200 breakdowns in that time forced lane closure after drivers couldn’t reach a refuge area. Highways England says this stretch has increased capacity by a third and made overall journeys more reliable.

A map of the UK's smart motorway system built from publicly available data of constructed and planned smart motorway systems, created by car insurance company Keith Michaels Insurance PLC

A map of the UK's smart motorway system built from publicly available data of constructed and planned smart motorway systems

Image credit: Smart Motorways UK | Keith Michaels Insurance PLC

If there’s no radar, it takes too long to spot an incident and send help, says the AA. Traditionally it takes 17 minutes for a control room to identify a breakdown using CCTV alone, three minutes to close the lane and reduce the speed limit, and further 17 minutes for breakdown cover to arrive. The AA and other roadside assistance won’t attend an incident unless police or traffic officers have successfully closed a lane. 

“And that’s 37 minutes sitting in a live traffic lane,” says Cousens. “Highways England’s own research showed in one case it took one hour to spot a stopped car in a live lane using just CCTV.”

Cameras can pan, tilt and zoom and cover the whole of the smart motorway network, but they can see only what the eye can see and have a limited range, says Eccleson – so CCTV will struggle in thick fog, heavy rain and at night. And the AA says it could have blind spots, depending on positioning. “If you’re downstream of a camera until it turns around, it won’t see you,” says Cousens. “We need to ensure there’s 100 per cent of coverage, 100 per cent of the time and that those cameras are constantly monitored in the control centres. 

Several cameras feeds at a time are monitored in seven Highways England regional control centres around the country. If one control centre becomes overloaded in case of multiple incidents, other control centres can watch the feeds instead, says Highways England, but it’s not possible to monitor every camera around the clock.

A network of road sensors – electromagnetic induction loops – have been in use for years in the UK’s motorways. This MIDAS system (motorway incident detection and automated signalling) detects the speed and length of a vehicle and feeds information into outstation units and automatically sets variable speed limits on motorways and major roads. Highways England traffic officers can also set speed limits. In theory, MIDAS detects breakdowns but doesn’t work as well when traffic is light, as a stopped vehicle might not affect the speed of others. But it’s then that cars will be driving faster, potentially towards a stopped vehicle, says Cousens.

“But the technology is 35 years old and ultimately will be replaced,” says Eccleson, whose company represents Smartmicro radars used on the continent in tolls and for traffic enforcement. “One of the biggest sources of failure is the metal loops which can cost £12,000 to £15,000 each to replace.” Radars could replace these carriageway loops more cheaply he argues, and potentially with more functionality. “It could feed straight back into an office, so if there’s a breakdown it could prompt human intervention sooner.”

Radar technology used on the two stretches of the M25 (J5-7 and J23-27) and being retrofitted on the stretch of the M3 is made by Navtech – who declined to comment – whose award-winning scanning radar ClearWay monitors a 500m stretch in each direction. This detects stopped vehicles and triggers an alert within 10 seconds, giving the exact stoppage location – and it works in all weather and lighting. “Radar overcomes a lot of weather issues, especially in this country,” says Eccleson.

Radar should be installed throughout the smart motorway system, says Cousens. But the technology does have limitations, he says – with stopped vehicle detection throwing up false alarms, particularly in high traffic flow with more stop-start traffic – meaning staff might waste their time investigating rather than spotting a real emergency.

Once alerted, control centre staff will switch a red X to close a lane via a sign on an overhead gantry. But drivers don’t always heed warning signs. Awareness of what this sign means has increased among drivers after campaigns by Highways England, but a frightening 180,000 drivers have already been issued with warning letters since the summer after being spotted driving in lanes marked as closed, and police plan to issue fines shortly. With more cameras and more variable speed limits, drivers are more likely to get fined. Even when variable limits aren’t in place, cameras can catch speeding motorists, and serious speeding can now prompt fines of up to £2,500 on motorways.

Smart motorways can be found in countries around the world, but no other nation has such ambitious expansion plans for smart motorways, says Cousens – but the UK does have exceptionally busy roads.

In the future, smart, connected cars should be able to “talk” to the nearest gantry and advise that it has stopped, set a red X and request help. “But the reality is that here and now, smart motorways are live - and we cannot afford to wait,” says Cousens. 

As well as more ERAs, retrofitted where possible, the AA has called for latest stopped vehicle detection systems on all stretches of smart motorway as soon as possible. It also calls for an end to dynamic hard shoulder motorways – switching to permanent live lanes instead – if numbers of ERAs and radars are increased – which comes down to budgets.

Better driver awareness combined with better use of the red X signs after an accident would increase safety – as would penalties for drivers who ignore the signs. “Safety cannot nor ever should be a compromising factor,” says Cousens.

Technology alone isn’t the answer “however utopic its promises” says Eccleson. “It now has phenomenal capability but needs more backroom development.”

Last month, transport secretary Grant Shapps released an ‘action plan’ to improve the safety of smart motorways. Indeed, this long-anticipated review – which was called in October 2019 but pulled in January after transport secretary Grant Shapps called for a more thorough assessment – has kept industry and campaigners on tenterhooks, with speculation that forthcoming smart sections due to open shortly might be abandoned.

“We look forward to the stocktake [already been published] and stand ready to implement its recommendations,” says a spokesperson from Highways England. “Any death on our roads is a tragedy.”

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