A 50mph speed limit will remain in place whilst contractors for Highways England test the technology before the first phase of the system goes live on a 7.5 mile stretch between junction 39 (Denby Dale) and junction 41 (Morley) on Saturday 12 December.
An extra lane will also open on the northbound carriageway between junction 41 and junction 42 (Lofthouse). Work is continuing between these junctions and a 50mph speed limit will remain in place until this phase of the smart motorway scheme goes live in the new year.
As part of the project, the latest technology is being installed to monitor traffic levels, provide traffic information to road users, and ease congestion by using variable speed limits on overhead message signs.
The hard shoulder will also be permanently converted into an extra lane between junctions 39 and 42 to provide extra capacity.
Contractors for Highways England have installed 6,172 road studs, put in nearly 7 miles of reinforced concrete barriers in the central reservation and resurfaced the same length on both carriageways. And they have also put in 10 gantries with 38 electronic signs as part of the full scheme.
Highways England project manager Tsuwun Bevan said:
Smart motorways are already proving successful in other parts of the country and we have now reached a stage where we can open this section of the M1 between junctions 39 and 41. By opening this extra lane it will help to reduce congestion during peak times for drivers by providing four lanes to ease the flow of traffic.
The overhead signs will display a mandatory 50mph speed limit for the first week while we test the technology but as from Saturday 12 December drivers will benefit from a variable electronic speed limit that will vary in response to the driving conditions.
Contractors will return to site in the new year to carry out some additional maintenance work such as bridge waterproofing and resurfacing of the carriageway. This will mean there could be overnight and weekend closures while this takes place.
By carrying this work out now it will mean that the network will not require any major maintenance work within the next 5 years, therefore improving the journey time and reliability for drivers in years to come.
For further information visit the scheme web page.
Members of the public should contact the Highways England customer contact centre on 0300 123 5000.
Journalists should contact the Highways England press office on 0844 693 1448 and use the menu to speak to the most appropriate press officer.