Smart motorway

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A smart motorway (formerly managed motorway) is a section of motorway in Great Britain which 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 flows, more reliable journey times, fewer road traffic collisions, and reduced noise and harmful vehicle emissions.[1][2] The term controlled motorway is used for schemes that use variable speed limits without hard-shoulder running (for example, the M25 from J27 to J30).

History[edit]

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 trialed 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]

Operation[edit]

The Highways Agency, Transport Scotland and Traffic Wales are responsible for the schemes in England, Scotland and Wales respectively.

Complete schemes, with variable speed limits and part-time hard-shoulder running, are in operation as follows:

Variable speed limits without hard-shoulder running are in operation on:

Variable speed limits with the hard-shoulder converted to a permanent running lane are in operation on:

Under construction[edit]

The following schemes are under construction:

Planned[edit]

The following schemes are due to be implemented during the 2010s:

Effectiveness[edit]

In 2007 it was estimated that ATM could be introduced within two years at a cost of around £5-15 million per mile[33] as opposed to 10 years and £79 million per mile for widening.[34][35]

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.[36] 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.[36] 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.[36] 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.[37]

The Highways Agency surveyed drivers, stating that 84% felt confident using the hard shoulder, 68% felt better informed about traffic conditions and that around 60% wanted the scheme expanding to other roads.[36]

Criticisms[edit]

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] The Highways Agency 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.[38]

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.[35] The Highways Agency rejected this concern based on the 5,000 miles of dual carriageway which doesn't have a hard shoulder.[39] 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.[39] 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.[35]

References[edit]

  1. ^ "M20 Junctions 4 - 7 Controlled Motorways". 
  2. ^ "Highways Agency - Our Road Network". 
  3. ^ "unknown". Highways Agency. 
  4. ^ "70mph speed limit on the M42 Active Traffic Management pilot". Highways Agency. Retrieved 2008-12-10. [dead link]
  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. ^ a b "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. ^ "M1 Jct 10 to 13 Improvements". Highways Agency. 
  13. ^ a b "M4 J19-20 and M5 J15-17 Managed Motorways". Highways Agency. 
  14. ^ "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. 
  15. ^ "Birmingham Box hard shoulder running goes live". 2009-12-01. 
  16. ^ "M62 J25 to J30 Managed Motorway". Highways Agency. 
  17. ^ "M1 Junctions 6A - 10 Controlled Motorway". Highways Agency. 
  18. ^ "M1 J25-28 Widening Scheme - Background information". Highways Agency. 
  19. ^ "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 
  20. ^ http://www.traffic-wales.com/AttachFiles/1275/M4%20Junction%2024-28%20Variable%20Speed%20Limit%20-%20Your%20Questions%20Answered.pdf. Traffic Wales. 
  21. ^ "M20 Junctions 4 - 7 Controlled Motorways". Highways Agency. 
  22. ^ "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. 
  23. ^ "M62 J25 to J30 Managed Motorway". Highways Agency. 
  24. ^ "M25 Junctions 5-7 Managed Motorways". Highways Agency. 
  25. ^ "M25 Junctions 23 to 27 Managed Motorways". Highways Agency. 
  26. ^ "M6 Junction 10A - 13 Managed Motorway". Highways Agency. 
  27. ^ "Intelligent Transport Systems". Transport Scotland. Retrieved 23 Oct 2012. 
  28. ^ "M60 Junction 8 to M62 Junction 20: Smart Motorway". Highways Agency. 
  29. ^ "M1 J28-31 Managed Motorways". Highways Agency. 
  30. ^ "M1 J32 to J35a Managed Motorway". Highways Agency. 
  31. ^ "M1 J39 to J42 Managed Motorway". Highways Agency. 
  32. ^ "M3 J2-4a Managed Motorway". Highways Agency. 
  33. ^ Cleland, Gary (2007-12-26). "No hard shoulder driving on M25". The Daily Telegraph (London: Telegraph News and Media). Retrieved 2007-12-31. 
  34. ^ 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. 
  35. ^ 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. 
  36. ^ a b c d Highways Agency (2007-10-25). "M42 Active Traffic Management Results –First Six Months" (PDF). Department for Transport. Retrieved 2007-12-31. [dead link]
  37. ^ 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. 
  38. ^ "How does it affect the environment?". M42 Jct 3a - Jct 7 Active Traffic Management. Highways Agency. Retrieved 2007-12-31. 
  39. ^ 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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