The project will help reduce congestion and improve journeys for drivers around Gaydon in Warwickshire.
The work was announced by the Chancellor in the 2012 Autumn Statement, and is scheduled for completion in spring 2016.
Transport Minister John Hayes said the start of work at this busy location was great news for drivers.
This new scheme will help cut queuing, boost safety and improve journeys, while unlocking potential economic growth in the area. It’s great news for the local community, local businesses and anyone who uses this junction that work is underway.
As part of the scheme, the Agency will lengthen the southbound exit slip road, install traffic lights on the junction and improve the northbound entry and exit slip roads.
It is expected that construction will take 12 months to complete.
Highways Agency project manager, Shah Hussain, said:
Junction 12 of the M40 is currently very busy, especially at peak times. It’s not uncommon to see queues forming in the morning – and this is something we want to tackle with this scheme.
Our work will boost the flow of traffic around this junction, reducing queues and improving journeys. We’re looking forward to delivering noticeable improvements.
The Agency said it had planned its work to cause minimum disruption.
We’ve focused our approach to this scheme on keeping traffic flowing,” Shah Hussain added. “We won’t start work until after the morning peak, and we will finish well before the evening peak.
We don’t anticipate that the construction work will have a great effect on traffic – but we will be monitoring the effects throughout and speaking to local people and businesses to check.
There will be temporary traffic lights and some reduced speed limits: these are necessary to help keep traffic flowing, and ensure our workforce stays safe as we carry out this project.
Work at the junction, in particular on the slip roads, will take place before 06:00am and after 09:00am on weekdays, and will finish by 4pm, to mitigate the effect on peak traffic. The Agency will also work through weekends.
The Highways Agency scheme to improve junction 12 will be complemented by work to create a dual carriageway on the B4451, being undertaken currently by Warwickshire County Council.
There will be speed limit restrictions for the duration of the works on the M40 and the B4451 Gaydon Road.
The joint effect of these schemes will be to greatly add to the capacity of local roads, and help support the growing local economy.
The Agency will publish regular updates on the work to keep drivers informed about the likely effect on their journeys.
For more information on the scheme, visit: the project pages.
Members of the public should contact the Highways Agency Information Line on 0300 123 5000.
Journalists should contact the Highways Agency press office on 0844 693 1448 and use the menu to speak to the most appropriate press officer.