In June 2025 Devon County Council commissioned M Group to start construction on the A382 Major Road Network improvements and a new Jetty Marsh link road at Newton Abbot, with the aim of achieving a low carbon highway using changes in materials, design and processes.
Client: Devon County Council
Project value: £32 million
Duration: September 2025 – autumn 2027
Situation
Historically, the A382 had poor alignment and visibility, while lacking pedestrian and cycle access. Its collision rate was higher than both the national and Devon County Council’s A-road average.
Challenge
The two-year project awarded to M Group includes two phases of improvements: building a link road at Jetty Marsh in a current floodplain and completing further road widening and realignment at Forches Cross.
As part of our commitment to safer, greener transport, M Group is working with Devon County Council alongside Exeter University, Department for Transport and ADEPT as part of the LiveLabs 2 project, with the aim of achieving a low carbon highway.
Our teams are trialling new methods and materials, and we’ll share any lessons that we learn on reducing carbon, both across our business and with the wider construction industry.
Accelerating carbon reduction and carbon initiatives into this scheme will provide valuable learning for the industry as a whole, as well as providing the opportunity for Devon County Council, Exeter University and M Group to showcase their green skills and capability in the southwest of England.”
Tom Morris, A382 Project Manager at M Group
Solution
Phase 1. Jetty Marsh
At Jetty Marsh, our teams have overcome the challenges of building a road on marshy ground and are:
- Constructing a link road on a new five-metre-high embankment in a current floodplain, with two large culverts to allow water to run through.
Embankment progress April 2025
- Reusing the material excavated on site to construct the embankment and create a new flood compensation area.
- Building a new roundabout where the old junction stood.
Roundabout kerbs being fitted
- Excavating to lower the ground by five metres to tie in with the current A382, with material being used to fill a landscape bund at Forches Cross.
Our teams worked alongside South West Water who were also on site, diverting high pressure water mains under the new roundabout. This work is now complete.
Phase 2. Forches Cross
At Forches Cross our teams will be:
- Working collaboratively with South West Water, Wales and West Utilities, National Grid, BT Openreach, Airband and Open Fibre Networks to implement extensive service diversions.
- Reducing the brow of the hill by a further three metres to allow for better visibility on approach to the new roundabout.
- Constructing a new roundabout on a three-metre-high embankment and crossing facilities at the current junction with Staplehill Road.
- Widening and realigning the road.
- Creating a new shared foot and cycle path using part of the old road.
Extensive engagement with local businesses and residents has been paramount during this project, due to the location of the road and its links into and out of Newton Abbot. A difficult decision to close the road means the project will take a year less than the three years that were originally planned.
The decision was a result of using state-of-the-art traffic modelling technology available and has allowed for traffic to flow more efficiently than if the road had remained open.
Result
Jetty Marsh roundabout is on track to be completed ahead of time and on budget by summer 2026. Forches Cross will then be closed to allow for the second phase of works, with the new Jetty Marsh link road and Forches Cross roundabout set to be opened to the public by autumn 2027.
These improvements will not only make the A382 safer, they’ll benefit local residents, businesses and visitors by easing current congestion, opening up the area to new growth and providing new cycling and walking links towards Dartmoor.
As we work towards completing a low carbon highway, here are some of our achievements and valuable learnings for reducing carbon to date:
- The highest carbon savings come from reducing and avoiding, which also reduce cost and in some cases programme. By closing the road, we’ve saved one year off the programme, and the preliminary costs associated with the one year saving conservatively equate to 1000Tco2e!
- By using responsibly sourced HVO, we’ve reduced the carbon of the fuel on site by 90 per cent. As hydrogen fuel usage becomes more readily available, we’re looking to reduce our carbon even further in future.
- Air source heating in the main project office has reduced the projected electricity usage by more than half, and our client commented that it was ‘the warmest site office’ they’ve ever been in. We’ve reused felled trees, using a local sawmill to create high-quality materials for the project. We’ve also replaced them with trees grown in a nursery, which are a larger size than would normally be planted in a highway scheme.
- The production of biochar has worked well, and we’ve had some valuable learning for M Group, Devon County Council and the specialist contractor Terrafix on how to make the process even more efficient in the future. We’re now working with our landscaping sub-contractor to develop a method of utilising the biochar as part of the soil decompaction process prior to planting.
