A smart motorway (formerly managed motorway) is a section of motorway in Great Britain that uses active traffic management (ATM) techniques to increase capacity by use of variable speed limits and hard shoulder running at busy times. Benefits include smoother traffic flow, more reliable journey times, fewer road traffic collisions, and reduced noise and harmful vehicle emissions.[1][2] The term controlled motorway is sometimes used for schemes that use variable speed limits without hard-shoulder running (for example, the M25 from J27 to J30).


The technique was first used in the UK on the M42 motorway in the West Midlands in 2006.[3] A higher speed limit of 60 miles per hour (97 km/h) was trialled on the southbound carriageway between junctions 4 and 3A from 2008 (a 10 miles per hour (16 km/h) increase on the previous maximum permissible speed).[4]

In 2007 plans were announced to extend the scheme to two sections of the M6 near Birmingham (4-5 and 8a-10) by 2011 for £150 million.[5] The emergency refuges were to be extended to every 800 metres (0.50 mi) on the roll out.[6] A study into the use of ATM on the M1, M4, M20 and M25 motorways was also announced,[5] however the Department for Transport had decided to proceed with a scheme to widen sections of the M25.[7]

A £2 billion contract was announced to extend the scheme to sections of the M1, M4, M5, M6, M60 and M62 in February 2010[8] with a further announcement by the new government in October 2010.[9] In March 2012 the government indicated that was considering a trial of higher 80 mph speed limit on some Managed Motorways[10] although proposals for higher speeds on motorways were met with caution on a number of grounds by both motoring and road safety organisations.[11]


Highways England (formerly known as the Highways Agency), Transport NI, Transport Scotland (who promote the technology as Intelligent Transport Systems)[12] and Traffic Wales are responsible for the schemes in England, Northern Ireland, Scotland and Wales respectively. In the following table, schemes are classified into 3 types:

  • Controlled motorway: Variable speed limits without hard-shoulder running
  • Dynamic hard shoulder: Variable speed limits with part-time hard shoulder running, where a demarcated hard shoulder still exists but messages on MS4 signs indicate whether it can be used as a lane or for emergencies only.
  • All lane running: Variable speed limits with the hard shoulder converted to a permanent running lane
  • Through junction running: On older schemes this referred to when a dynamic hard shoulder is maintained on a carriageway through a junction with MS4 signs indicating if it may be used or not. Newer schemes have no hard shoulder through junctions, even if there is a dynamic one between them.

As of April 2016 the following schemes are operational, under construction or planned:

Road Section Type Status
M1 J6a-J10[13] Controlled motorway Operational
M1 J10-J13[14] Dynamic hard shoulder Operational
M1 J16-J19[15] All lane running Operational
M1 J25-J28[16][17] Controlled motorway Operational
M1 J28-J31[18] All lane running Operational
M1 J31-J32 Controlled motorway Operational
M1 J32-J35a[19] All lane running Operational
M1 J39-J42[20] All lane running Operational
M3 J2-J4a[21] All lane running Operational
M4 J19-J20[22] Dynamic hard shoulder Operational
M4 J24-J28[23] Controlled motorway Operational
M5 J4a-J6[24] All lane running Operational
M5 J15-J17[22] Dynamic hard shoulder Operational
M6 J4-J10a[25] Dynamic hard shoulder Operational
M6 J10 Through-junction-running Operational
M6 J10a-J11a Controlled motorway Operational
M6 J11a-J13[26] All lane running Operational
M20 J4/J5-J7[27] Controlled motorway Operational
M25 J2-J3[28] Controlled motorway Operational
M25 J5-J6[29] All lane running Operational
M25 J6-J7 counter-clockwise[28] Controlled motorway Operational
M25 J6-J7 clockwise[29] All lane running Operational
M25 J7-J23[28] Controlled motorway Operational
M25 J23-J27[30] All lane running Operational
M5 J4a-J6[31] All lane running Operational
M25 J27-J30 Controlled motorway Operational
M40 J16-M42 J3a westbound Controlled motorway Operational
M42 J3a-J7[32] Dynamic hard shoulder Operational
M42 J7-J9 Controlled motorway Operational
M62 J18-J20[33] All lane running Operational
M62 J25-J26[34] All lane running Operational
M62 J26-J28[34] Dynamic hard shoulder Operational
M62 J28-J29 Controlled motorway Operational
M62 J29-J30 eastbound[34] Dynamic hard shoulder Operational
M62 J29-J30 westbound[34] All lane running Operational
M90: M9 J1a-J3, including bus lane from J1a and J2a[35] Dynamic hard shoulder Operational
M90 Queensferry Crossing[35] Operational
M1 J23a-J25 Controlled motorway (J23a-J24)

All lane running (J24-J25)

M4 J3-J12[36] Construction
M6 J2-J4[37] All lane running Construction
M6 J16-J19[38] All lane running Construction
M23 J8-J10[36] All lane running Construction
M27 J4-J11[36] All lane running Construction
M60 J8-J18[33] Controlled motorway Construction
M1 J13-J16 Planned
M1 J19- J23a[39] Planned
M3 J9-J14[36] Planned
M6 J13-J15[39] Planned
M6 J21a-J26[40] Planned
M20 J3-J5[36] Planned
M25 J10-J16 (Upgrade of controlled motorway)[36] Planned
M40 J16-M42 J3a[39] Planned
M42: M5 J4a-J3a(Birmingham Box: phase 4 smart motorway)[39] Planned
M53 J5-J11[40] Planned
M56 J6-J8[40] Planned
M60 J1-J4[40] Planned
M60 J24-J27[40] Planned
M62 J10-J12[40] Planned
M62 J20-J25[40] Planned


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

The map to the right visually represents the operational and under construction elements of the UK's current smart motorway system.[41]


In 2007 it was estimated that ATM could be introduced within two years at a cost of around £5-15 million per mile[42] as opposed to 10 years and £79 million per mile for widening.[43][44]

The M42 scheme was initially run as an experiment and a Highways Agency report into the first six months of the scheme showed a reduction in variability journey times of up to 27%.[5][6] The journey time statistics can be broken down to show that northbound journey times were reduced by 26%, equating to an average reduction of 4 minute as compared to the period when the variable speed limits were on but the hard shoulder was not being used and 9% southbound (equating to 1 minute) during the afternoon rush hour.[45] The report also indicated a fall in the number of accidents from over 5 a month to 1.5 per month on average.[5][6] The Agency did state that normally accident statistics should be compared over a 3-year period, so the initial results should be treated with caution. They also stated that no accidents had been caused by hard shoulder use as a normal lane.[45] The report also stated that there had been a 10% fall in pollution and 4% fall in fuel consumption.[5] The report also indicated a compliance rate of 98% to the indicated speed limits when using the hard shoulder.[45] For comparison before the introduction of mandatory speed limits at road works, the compliance rate was 10% as opposed to 89% afterwards, showing a similar effect.[46]


The Campaign for Better Transport argued that whilst it would reduce the need for widening schemes, it did nothing to reduce traffic and CO2 emissions. Friends of the Earth criticised the scheme as "widening on the cheap" and also pointed to a possible increase in vehicle emissions.[5] Highways England argue that ATM reduces the environmental impact in regards to widening as it is carried out within the existing boundaries of the motorway as well as a possible improvement in local air quality due to smoother traffic flow.[47]

The RAC cited a study in the Netherlands that showed drivers using the hard shoulder when they were not permitted, increasing the risk of a collision for vehicles stopped. The Royal Society for the Prevention of Accidents also expressed concern that emergency services would take longer to reach an incident.[44] The Highways Agency rejected this concern based on the 5,000 miles of dual carriageway that does not have a hard shoulder.[48] Disability groups were concerned that some drivers would not be able to access the emergency phones or even exit their vehicles, leaving them at increased risk.[48] Ruth Kelly, former Secretary of State for Transport stated that these schemes were useful, but that motorway widening would still be considered where it was appropriate.[44]


  1. ^ "M20 Junctions 4 - 7 Controlled Motorways". 
  2. ^ "Highways England - Our Road Network". 
  3. ^ "unknown". Highways Agency. 
  4. ^ "70mph speed limit on the M42 Active Traffic Management pilot". Highways Agency. Archived from the original on 2008-08-06. Retrieved 2008-12-10. 
  5. ^ a b c d e f "'Extra lane' plan to be extended". BBC News. British Broadcasting Corporation. 2007-10-25. Retrieved 2007-12-31. 
  6. ^ a b c Meikle, James (2007-10-26). "Kelly extends experiment to let drivers use hard shoulder". The Guardian. London: Guardian News and Media Limited. Retrieved 2007-12-31. 
  7. ^ Milmo, Dan (2007-12-24). "Plan to open up hard shoulder on M25 to ease traffic shelved". The Guardian. London: Guardian News and Media Limited. Retrieved 2007-12-31. 
  8. ^ "£2 Billion In Managed Motorway Schemes Starts On UK Highways". GovMonitor. 2010-02-18. 
  9. ^ "Transport Secretary gives the go-ahead to 24 New Schemes and announces over £600M of further funding". Department for Transport. 2010-10-26. 
  10. ^ "80mph speed limit trial on managed motorways". Local Transport Today. 
  11. ^ "Motorways to get 80mph speed limit despite claims they are 'not safe enough' to cope". Daily Mail. London. 2012-05-14. 
  12. ^ "Technology and Traffic Scotland - Intelligent Transport Systems". www.transport.gov.scot. Transport Scotland. Retrieved 18 August 2016. 
  13. ^ "M1 Junctions 6A - 10 Controlled Motorway". Highways England. 
  14. ^ "M1 Jct 10 to 13 Improvements". Highways England. 
  15. ^ "M1 J16 to J19 Smart Motorway". Highways England. 
  16. ^ "M1 J25-28 Widening Scheme - Background information". Highways England. 
  17. ^ "Smoother, more reliable and safer journeys on the M1 in the East Midlands". Road users will benefit from improved journey time reliability and safety as new congestion-tackling variable mandatory speed limits are introduced to maximise the benefits of the widened M1 in Nottinghamshire and Derbyshire from Wednesday 18 May 2011 
  18. ^ "M1 J28 to J31 Smart Motorway". Highways England. 
  19. ^ "M1 J32 to J35a Managed Motorway". Highways England. 
  20. ^ "M1 Junctions 39-42: Smart Motorway". Highways England. Retrieved 10 February 2015. 
  21. ^ "M3 J2-4a Managed Motorway". Highways England. 
  22. ^ a b "M4 J19-20 and M5 J15-17 Managed Motorways". Highways England. 
  23. ^ "M4 J24 to J28 Managed Motorway" (PDF). Traffic Wales. Retrieved 22 December 2014. 
  24. ^ "M5 Junctions 4a to 6 Smart Motorway". www.highways.gov.uk. Highways England. Retrieved 15 January 2016. 
  25. ^ "Minister welcomes delivery of M6 Managed Motorways scheme". Vehicles travelling on the busy 6.7-mile stretch of the M6 between junction 8 and 10A are now able to use the hard shoulder as a traffic lane during busy periods. This is the second successful section of hard shoulder running that consulting and business services Group Mouchel and contractor Carillion has supported the Highways Agency to deliver on the M6 in the last 18 months. This latest section follows the successful opening of the Managed Motorways scheme on the M6 between junctions 4 and 5 in December 2009. 
  26. ^ "M6 Junction 10A - 13 Managed Motorway". Highways England. 
  27. ^ "M20 Junctions 4 - 7 Controlled Motorways". Highways England. 
  28. ^ a b c "M25 speed limit work in Surrey comes to end". BBC News. 2011-04-16. The clockwise carriageway between junction nine at Leatherhead and junction 10 for the A3 will be closed from 2200 until 0600 BST on Sunday. The road has been closed each weekend since 29 January to allow installation of eight new overhead gantries. It is part of a project to extend the M25 controlled motorway system. The system, already in place between junctions 10 and 16, uses variable speed limits to reduce stop-start congestion during busy periods. 
  29. ^ a b "M25 Junctions 5-7 Managed Motorways". Highways England. 
  30. ^ "M25 Junctions 23 to 27 Managed Motorways". Highways England. 
  31. ^ "M5 Junctions 4a to 6 Smart Motorway". www.highways.gov.uk. Highways England. Retrieved 15 January 2016. 
  32. ^ "Birmingham Box hard shoulder running goes live". 2009-12-01. 
  33. ^ a b "M60 Junction 8 to M62 Junction 20: Smart Motorway". Highways England. 
  34. ^ a b c d "M62 J25 to J30 Managed Motorway". Highways England. 
  35. ^ a b "Intelligent Transport Systems". Transport Scotland. Retrieved 23 Oct 2012. 
  36. ^ a b c d e f "Major roads investment in London and the south east". Gov.uk. Department for Transport, HM Treasury. Retrieved 3 April 2015. 
  37. ^ "M6 J2-J4 Smart Motorway". Highways England. 
  38. ^ "M6 Junctions 16-19: Smart Motorway". www.highways.gov.uk. Highways England. Retrieved 29 February 2016. 
  39. ^ a b c d "Major roads investment in the Midlands". Gov.uk. Retrieved 3 April 2015. 
  40. ^ a b c d e f g "Major roads investment in the North West". Gov.uk. Retrieved 10 February 2015. 
  41. ^ "Smart Motorways UK Smart Motorway Map". Keith Michaels PLC. Retrieved 2017-07-03. 
  42. ^ Cleland, Gary (2007-12-26). "No hard shoulder driving on M25". The Daily Telegraph. London: Telegraph News and Media. Retrieved 2007-12-31. 
  43. ^ Webster, Ben (2007-10-25). "Hard-shoulder driving lies ahead for motorways in effort to reduce congestion". The Times. London: News International Limited. Retrieved 2007-12-31. 
  44. ^ a b c Strange, Hannah; Ben Webster (2007-10-25). "Hard shoulder scheme cut journey times on motorways". Times Online. London: News International Limited. Retrieved 2007-12-31. 
  45. ^ a b c Highways Agency (2007-10-25). "M42 Active Traffic Management Results –First Six Months" (PDF). Department for Transport. Archived from the original (PDF) on 2008-03-06. Retrieved 2007-12-31. 
  46. ^ Murray, Louise (2005-10-26). "Smooth-flowing traffic is on the way". Society - The Guardian. London: Guardian News and Media Limited. Retrieved 2007-12-31. 
  47. ^ "How does it affect the environment?". M42 Jct 3a - Jct 7 Active Traffic Management. Highways Agency. Retrieved 2007-12-31. 
  48. ^ a b Sturcke, James; Agencies (2006-08-31). "Motorway hard-shoulder use 'could cost lives'". Guardian Unlimited. London: Guardian News and Media Limited. Retrieved 2007-12-31. 

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