Editing M1 motorway (section)

=== Smart Motorways ===
==== M1 widening and variable speed limits, junctions 6A to 10 (M25 to Luton South) ====
Work began on the {{convert|10|mi|km|adj=on}} section between the [[M25 motorway|M25]] and Luton (J6A-J10) in 2006 and opened in 2009, which included the construction of new parallel [[Local–express lanes|collector-distributor lanes]] between junctions 7 and 8.

The [[M10 motorway (Great Britain)|M10]] spur was built as a motorway because it inevitably led to the M1, but as non-motorway traffic could now travel between the A414 at Hemel Hempstead and Park Street Roundabout without having to access the M1, the M10 was downgraded to an [[Great Britain road numbering scheme|A road]], and designated as part of the [[A414 road|A414]] to allow for this. The work also included widening or replacement of 11 underbridges on one or both carriageways, and replacing seven overbridges<ref>{{cite web|title=M1 Jct 6a to 10 Widening|url=http://www.highways.gov.uk/roads/projects/4478.aspx|url-status=dead|archive-url=https://web.archive.org/web/20090916021803/http://www.highways.gov.uk/roads/projects/4478.aspx|archive-date=16 September 2009|publisher=Highways Agency}}</ref> at a total cost of £294&nbsp;million.<ref>{{cite web|title=9 Mar 2009 : Column 10W—continued|url=https://publications.parliament.uk/pa/cm200809/cmhansrd/cm090309/text/90309w0003.htm|work=Hansard}}</ref> A [[Smart motorway|variable mandatory speed limit]] system was installed, making this the first [[smart motorway]] scheme on the M1.

==== M1 dynamic hard shoulder running, junctions 10 to 13 (Luton South to Milton Keynes South) ====
Work to introduce [[Smart motorway#Dynamic hard shoulder running|dynamic hard shoulder running]] on approximately {{convert|15|mi|km}} of motorway between Luton and Milton Keynes (J10-J13) was completed in December 2012, at a total cost of £327&nbsp;million.<ref>{{cite web|title=M1 Junctions 10–13 Improvements|url=http://www.highways.gov.uk/roads/road-projects/m1-junction-10-13-improvements/|url-status=dead|archive-url=http://webarchive.nationalarchives.gov.uk/20140207102850/http://www.highways.gov.uk/roads/road-projects/m1-junction-10-13-improvements/|archive-date=7 February 2014|publisher=Highways Agency}}</ref> This made the hard shoulder available to be opened as a traffic lane where additional capacity was necessary. Modifications were made to junctions 11 and 12,<ref name="HA5">{{cite web|title=M1 Jct 10 to 13 Improvements|url=http://www.highways.gov.uk/roads/projects/4482.aspx|url-status=dead|archive-url=https://web.archive.org/web/20120629032930/http://www.highways.gov.uk/roads/projects/4482.aspx|archive-date=29 June 2012|publisher=Highways Agency}}</ref> to allow for four lanes running through each junction, and the [[A421 road|A421]] from junction 13 to the [[Bedford]] southern bypass was also upgraded to two lanes each way during this period.<ref>{{cite web|title=A421 Bedford to M1 Junction 13|url=http://www.highways.gov.uk/roads/projects/4584.aspx|url-status=dead|archive-url=https://web.archive.org/web/20110605115952/http://www.highways.gov.uk/roads/projects/4584.aspx|archive-date=5 June 2011|publisher=Highways Agency}}</ref> The scheme will likely be converted to [[Smart motorway#All lane running|all lane running]] at some point in the 2020 decade, alongside all other dynamic hard shoulder running schemes. This was because a Government review into smart motorways found dynamic hard shoulder running was too confusing for drivers, leading to plans to convert all dynamic hard shoulders into permanent running lanes.<ref>{{cite web|last=|title=Action plan announced to boost smart motorway safety|url=https://www.gov.uk/government/news/action-plan-announced-to-boost-smart-motorway-safety|access-date=19 June 2020|website=GOV.UK}}</ref>

==== M1 widening and variable speed limits, junctions 25–28 (Nottingham to Mansfield) ====
Work to widen the {{convert|15|mi|km|adj=on}} section from Nottingham to [[Mansfield]] (J25-J28) to four lanes each way began in October 2007 and was completed in May 2010, at a cost of £340&nbsp;million.<ref>{{cite web|title=M1 widening J25-28: work to reduce congestion and improve safety starts in earnest|url=http://www.highways.gov.uk/news/newsroom.aspx?pressreleaseid=156326|url-status=dead|archive-url=https://web.archive.org/web/20110605130555/http://www.highways.gov.uk/news/newsroom.aspx?pressreleaseid=156326|archive-date=5 June 2011|access-date=20 January 2008|publisher=Highways Agency}}</ref><ref>{{cite web|title=£340m M1 contract to MVM consortium|url=http://www.emcbe.com/january-constructive-article6.html|url-status=dead|archive-url=https://web.archive.org/web/20160117183458/http://www.emcbe.com/january-constructive-article6.html|archive-date=17 January 2016}}</ref> A 50&nbsp;mph limit, enforced by [[Traffic enforcement camera|average speed cameras]], was imposed for the period of construction, but it proved to be so effective that a permanent variable mandatory speed limit system was installed.<ref>{{cite news|date=3 January 2010|title=M1 works speed cameras will stay|work=BBC News|url=http://news.bbc.co.uk/1/hi/england/nottinghamshire/8438375.stm|quote=Temporary cameras installed for widening road works between junctions 25 and 28 have proved so effective they will stay, it has been confirmed.}}</ref> In 2023, following a previous debate on the issue, local MPs [[Mark Fletcher (politician)|Mark Fletcher]] and [[Lee Anderson (British politician)|Lee Anderson]] called on the government to upgrade junction 28, describing it as a "pinch point" disadvantaging local residents and businesses.<ref>[https://www.chad.co.uk/news/transport/mps-to-gather-in-westminster-to-call-for-improvements-to-m1-junction-near-mansfield-4142811 MPs to gather in Westminster to call for improvements to M1 junction near Mansfield] ''Chad'', 16 May 2023. Retrieved 27 December 2023</ref><ref>[https://www.bbc.co.uk/news/uk-england-derbyshire-67661397 M1: New plans for junction 28 upgrade to be sent to government] ''[[BBC News]]'', 11 December 2023. Retrieved 27 December 2023</ref>

==== M1 widening and variable speed limits, junctions 13–16 (Milton Keynes South to Northampton West) ====
National Highways converted the existing {{convert|23|mi| adj = on}} section of the M1 between Milton Keynes and Northampton (J13-J16) into an all-lane-running (ALR) smart motorway consisting of four lanes running in both directions without a hard shoulder, with the project's cost being £373{{nbsp}}million. Construction began in January 2018, with the scheme opening in stages until 9 March 2023, when the project was fully complete.<ref>{{cite web |url=https://nationalhighways.co.uk/our-roads/east/m1-junction-13-to-junction-16-smart-motorway/#documents |title=M1 junction 13 to junction 16: smart motorway |publisher = National Highways |date = 9 January 2023 |access-date = 22 January 2023}}</ref>