Network Rail Creates Digital Twin of Historic Severn Tunnel, Revolutionizing Maintenance

• 6 December 2025
• Construction Focus
• 1268 Views

Network Rail has successfully deployed a comprehensive, multidisciplinary digital twin of the historic Severn Tunnel, a vital 7-kilometer rail link connecting England and Wales since 1886.

This innovative move leverages modern technology to dramatically improve the maintenance and management of the 137-year-old structure, which currently sees over 32,000 trains pass through it annually.

The Severn Tunnel presents significant maintenance challenges, including constant water leaks, harsh working conditions, and the unavoidable wear and tear of time.

To address these issues and ensure the tunnel’s safe and reliable operation for years to come, Network Rail engineers used a suite of Bentley applications. Tools such as MicroStation, OpenRail Designer, ProjectWise, Bentley iTwin platform, and iTwin Experience were utilized to tackle challenges in different areas of work.

This federated digital twin consolidates disparate information, including an accurate 3D model of the tunnel lining, track, signaling, drainage, and overhead line equipment, into a single source of truth accessible through the Bentley iTwin Platform. ProjectWise was implemented as the common data environment (CDE), linking over 30,000 asset images to the models.

These tools helped minimize disruption and improve safety within the project. The firm achieved a 50% reduction in physical site visits and a 70% decrease in manual surveys. Besides, the project led to a 60% improvement in document management, facilitating faster access to critical information and more seamless collaboration across teams. Furthermore, by completing the complex 3D rail asset model in-house, Network Rail achieved a saving of £350,000.

The successful deployment of the Severn Tunnel digital twin is a key driver for Network Rail’s broader digital railway initiative, which plans to extend this approach across 250 miles of track and major stations.

• iTwin
• ProjectWise
• MicroStation
• Bentley Systems
• OpenRail