Rise of smart motorways


Posted on: September 6, 2019 by Jennie Martin

Smart motorways have had a mixed press. Public conversations and mainstream media have questioned whether hard shoulders should be lost as permanent refuge areas. Evidence shows, however, that they are dangerous spaces not suitable for refuge for more than a few seconds.

There are, of course, other major challenges in managing and delivering the UK’s road infrastructure. Acquiring new land to build additional road capacity is costly and can be difficult. At the same time, the environmental impact of road vehicles must be managed.

Highways England’s Smart Motorways program started in 2006 with the M42 pilot. This was not a leap in the dark: the Dutch highways administration had been working on a similar concept that had itself evolved from early work by Highways England. Yet it was still a significant step, building on significant advances in detection and control technology, on the vastly improved reliability of vehicles since the English motorway design was conceived in the 1950s, and on the excellent safety record on UK roads. It was also driven by the need to increase capacity and traffic flow without expanding motorways themselves. While it is easy to see how these factors drove the smart motorway concept, it has taken visionary and determined management to make the first schemes happen and ensure the concept be permanently adopted.

Smart motorways at a glance

All forms of smart motorway depend on technology for their safe and effective operation. They are an excellent example of intelligent transport systems in daily use.

Smart motorways come in three types.

  • Controlled motorways, the original concept, which only uses mandatory variable speed limits to optimize the efficiency of the motorway; this was a significant innovation in its time
  • Hard shoulder running, which involves switching the hard shoulder in and out of general traffic use depending on traffic conditions and whether the hard shoulder is in use for an emergency; this was the concept first trialed in 2006
  • All lane running, the permanent conversion of the hard shoulder into an additional traffic lane, is the latest step. The lack of a hard shoulder is partly mitigated in that modern vehicles do not break down as often as they did when motorways started, and partly by the installation of refuges. In the light of concerns about access to refuges, there is a gradual move towards having them once a mile instead of every mile and a half.

Measurable benefits

Over the life of its smart motorways program, and in response to growing demand for road space and strong criticism of disrupted and unpredictable journeys, Highways England evolved and matured the M42 pilot into a permanent policy. Now, smart motorways have been in operation for so long that evaluation results are available.

Before smart motorways, congestion on the network caused 25% of accidents and the cost of congestion was estimated at £2 billion per year. By reducing congestion, smart motorways are reducing both figures. They have proved to be at least as safe as before, and on some routes there are fewer accidents. The current implementation plan will have added 400 miles of lane capacity when it is complete, making a significant inroad into congestion. Less publicized, but increasingly important, is that by making traffic flow smoother, smart motorways reduce emissions both from engines and from tire/roadway friction.

The smart motorway implementations by Highways England in their various forms demonstrate the capacity for innovation, even in the face of mixed public opinion. Highways England has faced demand for keeping the hard shoulder on questionable grounds of safety, and equally strong demands for not using up any additional land at all to create brand-new road space.

Pioneering intelligent transport systems

Highways England’s 2015-2020 Business Plan includes a total of 15 smart motorway schemes. At present, four are completed, five are underway and six are planned. The final outcome will be a significantly improved network in terms of congestion, safety and air quality, at much less financial and environmental cost than building new capacity from scratch.

The UK led the world in the early adoption of intelligent transport systems in the 1980s. While other countries have now caught up, the smart motorways scheme stands as an example of the kind of pioneering intelligent transport systems implementation that is ongoing in the UK.

A successful, safe and sustainable road transport network will continue to be a critical part of the country’s mobility mix. Innovative deployment of connected technologies and increased use of data, analytics and artificial intelligence will enable the UK to stretch capacity and minimize disruption while leveraging existing road infrastructure. Increased use of data from smart motorways, combined with smart technologies such as advanced telematics, the evolution of connected and autonomous vehicles, and urban and inter-urban traffic flow management will all be essential to meeting major environmental and cost challenges. Critically, a key benefit of continued technological innovation is that for drivers, passengers and pedestrians, a safer future will be secured.

Smart motorway technologies

  • Vehicle detection systems provide data on traffic flow which is processed into the automated or semi-automated setting of variable message signs and variable speed limit signs on the smart motorway. It is also used for other purposes such as traffic information and route planning. Highways England’s system uses inductive loops in the road (the traditional technology) and radar (a later development) to detect vehicle numbers, types and speed.
  • CCTV is an important part of the portfolio. The actual hard shoulder is 100% visible via CCTV to the control center and the rest of the motorway has good visibility, varying slightly according to location. The cameras are essential when opening a dynamic hard shoulder to general traffic, in order to check for obstructions, and helpful to operators at all times since we are not yet at the point of total automation of these processes.
  • Digital speed enforcement cameras cover all lanes of traffic with one camera, and automatically recalibrate to take into account changes in the variable speed limits.

Digital Vision for Mobility

This article is part of the Atos Digital Vision for Mobility opinion paper. We explore opportunities and challenges for transport and logistics providers in this rapidly evolving space, where transport and logistics are leading other markets in digital transformation.

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About Jennie Martin

Secretary General, ITS UK
Jennie joined ITS United Kingdom, the Intelligent Transport Society for the UK, in 1998.  Prior to that, she worked in the City Engineer’s Department at the Corporation of London, the local authority for the “Square Mile” financial district of London.  Jennie began her working life with the then British Rail in 1986. Jennie has a BA (Hons) from Kings College London, and an MA from the UK’s Open University.  She wrote her MA thesis on the institutional framework of the introduction of camera technology for traffic applications in London. She started with ITS (UK) as Membership Secretary and was promoted to Secretary General in 2004. Jennie is a past Chairman of the Network of National ITS Associations, an organisation of 28 European ITS associations.  She is active in various European and world-wide ITS projects and forums, and is a member of the British Standards Institute’s ITS Committee.  She was part of the host country committees for the ITS Congresses in London 2006, Dublin 2012 and Glasgow 2016. Jennie is originally from Sweden but is now a happily naturalised Londoner.

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