Smart motorway

A smart motorway (formerly managed motorway and active traffic management), also known in Scotland as an intelligent transport system, is a section of motorway in the United Kingdom (primarily in England) that employs active traffic management (ATM) techniques to increase capacity through the use of MIDAS technology including variable speed limits and occasionally hard shoulder running and ramp metering at busy times. They were developed at the turn of the 21st century as a cost-effective alternative to traditional carriageway widening, with intended benefits ranging from more reliable journey times to lower vehicle emissions. However, despite the risk of a collision occurring between two moving vehicles being found to be decreased, there has been an acknowledged rise in the incidence of collisions involving vehicles where at least one was stationary in the first few years following the widespread removal of the hard shoulder on the country's busiest sections of motorway. Smart motorways garnered intense criticism from politicians, police representatives and motoring organisations, particularly from 2020 onwards, after a surge in near miss incidents and dozens of fatalities were revealed.
The term controlled motorway is sometimes used for schemes that use variable speed limits without hard-shoulder running (for example, the M25 London Orbital between junction 27 and junction 30).
History.
The traffic management technique, including hard shoulder running, was first used in its full specification in the UK on the M42 motorway in the West Midlands in 2006. A higher speed limit of was trialled on the southbound carriageway between junctions 4 and 3A from 2008 (a increase on the previous maximum permissible speed).
In 2007 plans were announced by the then secretary of state for transport, Ruth Kelly, to extend the scheme to two sections of the M6 motorway near Birmingham (4-5 and 8a-10) by 2011 at a cost of £150 million. The emergency refuges were to be extended to every on the roll out. A study into the use of ATM on the M1, M4, M20 and M25 motorways was also announced, however the Department for Transport had decided to proceed with a scheme to widen sections of the M25.
A £2 billion contract was announced to extend the scheme to sections of the M1, M4, M5, M6, M60 and M62 in February 2010 with a further announcement by the new government in October 2010. The contract was awarded to four delivery partners Balfour Beatty, Carillion and joint ventures BAM Nuttall/Morgan Sindall Group and Costain Group/Serco. In January 2012, Carillion won the contract for M6 junctions 5 - 8 near Birmingham for £126 million.
From 2013 the current term "smart motorway" was used by the Highways Agency (now Highways England) to promote the technology to road users.
In January 2018, the contracts previously awarded to Carillion were taken on by Kier, following its entry into compulsory liquidation.
In April 2021, the government announced that new smart motorways would include radar, to detect vehicles which had stopped, and additional cameras to aid the detection (and subsequent prosecution) of motorists using lanes which are marked as being closed. The government stated that existing smart motorways would have these additional safety features installed by September 2022.
Map.
The map to the right visually represents the operational and under construction elements of the UK's smart motorway system as of June 2017.
Effectiveness.
In 2007 it was estimated that ATM could be introduced within two years at a cost of around £5-15 million per mile as opposed to 10 years and £79 million per mile for widening.
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 of journey times of up to 27%. 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 minutes 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. The report also indicated a fall in the number of accidents from over 5 a month to 1.5 per month on average. 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. The report also stated that there had been a 10% fall in pollution and 4% fall in fuel consumption. The report also indicated a compliance rate of 98% to the indicated speed limits when using the hard shoulder. 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.
Criticisms.
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. 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.
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. The Highways Agency rejected this concern based on the of dual carriageway that does not have a hard shoulder. 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. 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.
The scheme has attracted criticism from motoring organisations such as the AA, who in 2018 reported that many members were concerned that speed limits were being imposed without good cause in situations where traffic was light. In response, Highways England stated that they had "started a comprehensive review of how variable speed limits are set, including the amount of time they are visible to drivers".
A campaign "Smart Motorways Kill" was set up in 2019 after the death of Jason Mercer and Alexandru Murgeanu on the M1 northbound near junction 34. They were killed when a heavy goods vehicle collided with their stationary vehicles, after they had pulled over following a minor accident. The lane they were in was not closed until after they were killed. The campaign is bringing a judicial review against Highways England to have smart motorways banned and they have also reported H.E to the police for criminal manslaughter. They are also looking at bringing a disability discrimination complaint and class action.
In January 2020, it was announced that a review was planned after freedom of information requests showed that near misses had increased up to 20-fold, and that 38 people had died. The emergency refuge areas (ERA) were placed apart on the M42 pilot scheme, but can be apart on stretches of the M25. Only 9% of drivers feel safe while using smart motorways. Some of the extra capacity is negated by drivers terrified to drive on the inside lane and not using them. 
A BBC "Panorama" aired on 27 January 2020 alleged that smart motorways had caused multiple deaths in the UK, and that the conversion of part of the M25 to "all-lane running" yielded a 2000% increase in hazardous "near misses".
On 28 January 2020 Police Federation of England and Wales chief, reported "The Times" newspaper, John Apter said he "did not like the term 'smart motorways'" because it infers that they are a good idea. "They’re anything but" and "a recipe for disaster. It’s a death trap. It’s inherently dangerous and putting lives at risk."
In January 2020, all "Smart Motorways" were put under review to address safety concerns and determine an action plan. No new such motorways would open until this review was published. On 12 March 2020, the review and action plan was published. It stated changes to the standards for new smart motorways (ones which had not started construction) such as a reduction from upto 1.5 miles to 1 mile between Emergency refuge areas (or other qualifying areas) and Stranded vehicle detection radars to be installed as part of the project. Other actions it required to be taken is for all Dynamic Hard Shoulder Motorways to be converted into All-Lane-Running by March 2025, Stranded Vehicle Detection radars to be installed on all Smart Motorways within 36 months & a potential national programme to install more ERAs on current smart motorways.
In 2021, Labour Police and Crime Commissioner from South Yorkshire Alan Billings criticised smart motorways. The same year, the government announced the retrofitting of the entire network with radar and improved cameras, and paused the construction of any more smart motorways until this was implemented.
Specifications.
Early systems used dot matrix signs on gantries to display short text messages, with smaller variable signs above each lane and to the sides of the carriageway. Current smart motorway systems often use the "MS4" sign type which can include pictograms from the Traffic Signs Regulations and General Directions.
In 2017, Highways England trialled a new type of emergency area on the M3 that would be more visibly obvious to motorists. A new sign accompanied the trial which is similar in design to European emergency area signs. These changes have subsequently been trialled on the M5 and M25 with the signs being authorised by the Department for Transport for further use.
Operation and variants.
Highways England, the South Wales Trunk Road Agent (there are no motorways in North Wales), Transport NI (Northern Ireland) and Transport Scotland are responsible for the construction and maintenance of smart motorways in their respective countries.
Controlled motorway.
Variable speed limits with the hard shoulder operating as it would on a conventional motorway. They have most often been installed where a motorway has previously been widened but with a discontinuous hard shoulder to incorporate existing bridges, therefore using the hard shoulder as a running lane is ruled out. Existing gantries are upgraded to support signals capable of displaying a mandatory speed limit and speed cameras.
Dynamic hard shoulder running.
Variable speed limits with the hard shoulder selectively opened as a running lane during periods when traffic levels are too high for only three lanes of running traffic. When activated, vehicles can use the hard shoulder as a running lane. All lanes are limited to a maximum of 60 mph, but these can be lowered further.
In October 2019, the chief executive of Highways England told MPs that the company has no plans to introduce the configuration to any further section of motorway, after admitting that motorists found the setup 'too confusing' to use. A study conducted in the previous month found that more than half of motorists surveyed would not drive on a hard shoulder even if it was open.
A stocktake taken in March 2021 confirmed that all DHSR smart motorways will end the use of them by March 2025 by converting all current DHSR to ALR. 
All lane running.
Variable speed limits with the hard shoulder removed and converted to a permanent running lane.
Through-junction running.
Isolated stretches on a smart motorway where the hard shoulder becomes a permanent running lane through a junction and immediately surrounding the slip roads.
Under construction.
The following schemes are under construction:
Withdrawn schemes.
The above sections of motorway were included in the first five-year road investment strategy published in December 2014, however they have been removed from the second and current strategy. Sections of the M1 in Leicestershire and Yorkshire are billed to receive undescribed 'capacity improvements' in the third road period beginning in 2025.
The M4 between junctions 24 and 28 near Newport in south Wales had its variable speed limit replaced with a permanent average speed camera-enforced 50mph limit in early 2021. The Welsh Government believed that changing to a fixed limit would better reduce congestion and improve the quality of the air in the town.
Fatalities.
In September 2018, 22 minutes elapsed before warnings of a car breakdown were communicated to following traffic. In the meantime, a fatality occurred. Total fatalities in the UK number at least 38.