A38 Saltash Tunnel modernisation plans announced

National Highways has announced the commencement of the second phase of a significant modernisation project for the A38 Saltash Tunnel, set to begin later this autumn. 

This initiative is part of a ‘generational’ refurbishment aimed at upgrading the tunnel’s infrastructure, which has been in operation for 36 years.

The tunnel forms a key route for those coming from Plymouth and Ivybridge into Cornwall. 

The upgrade will enhance the Tunnel and Traffic Control System, including improvements to electrical distribution, new LED lighting, ventilation fans, and electronic signage. 

This essential £25 million programme comes as the tunnel accommodates approximately 40,000 vehicles daily and is noted for being the only tunnel in Europe operating under tidal flow conditions.

Julian Mitchell, National Highways’ Tunnel Manager, said: “The tunnel is safe but it is essential that we replace our systems which have been operating for 20-plus years, to make the tunnel fit for now and for the future.”

The existing tunnel and lane control system, nearing the end of its operational life, will be replaced to ensure ongoing safety, reliability, and efficiency for road users. 

Initial preparatory work has already begun, with old cabling being stripped out in parallel with a recent speed reduction scheme that lowered the limit from 70mph to 50mph between the tunnel and Carkeel roundabout. 

New average speed cameras have also been installed to enforce a 30mph limit through the tunnel and surrounding diversion routes.

Key elements of the upgrade include:

• Renewal of the tunnel control and traffic management system.
• Installation of energy-efficient LED lighting.
• Implementation of a modern electrical power distribution system featuring fibre cabling.
• Upgraded ventilation control to enhance air quality management.
• Replacement of existing sensors for improved air quality monitoring.
• Installation of traffic signals and automatic barriers for enhanced safety.
• Improved information signage and easy-access cable duct covers.

Work is scheduled to commence in late November and will take approximately 12 months to complete. 

During this period, the tunnel will be closed overnight on weekdays from 8pm to 6am, with drivers advised to use the B3271 and North Road diversion routes.

From late November until spring 2025, the inner westbound lane of the A38 will also be narrowed to facilitate the installation of sign foundations. #

Following spring 2025, the tunnel will operate with fixed lanes rather than tidal flow, with clear lane designations for traffic.

Mr Mitchell added: “We appreciate the scheme will have some impact on road users and Saltash residents, but we’re keeping the closures to an absolute minimum, and we thank all drivers and residents in advance for their co-operation and patience ahead of starting work on this generational upgrade.”

For further details on the modernisation project and other initiatives by National Highways in the South West, visit National Highways.