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Rail — infrastructure
Rail — infrastructureDrainage upgrade, tunnel refurbishment

Balcombe Tunnel Drainage Works (as part of Brighton Main Line Upgrade)

Balcombe Tunnel, West Sussex, UK · 2019 (major works completed February 2019) · Part of £67m (Brighton Main Line investment)

The judgement call

Account-gated at launch

The drainage works were critical for improving the reliability and safety of the Brighton Main Line, a vital commuter route. - Highlights the ongoing challenge of maintaining and upgrading Victorian-era railway assets to meet modern demands. - The project demonstrates the importance of effective drainage for track stability and operational performance.

Key engineering challenges

Rebuilding and upgrading Victorian-era brick culvert drainage within an operational railway tunnel. - Addressing persistent issues of water ingress and build-up that damaged tracks and caused delays. - Working in a confined tunnel environment with limited access and strict safety protocols. - Minimising disruption to services on the busy Brighton Main Line during the works.

Project facts

Client / owner
Network Rail
Lead contractor
Lead designers
Project type
upgrade, refurbishment
Scale
Extensive drainage works; rebuilding Victorian brick culvert drainage.
Disciplines
civil; geotechnical; project management
Standards & frameworks
Network Rail standards

Sources: Network Rail Media Centre (Feb 2019, https://www.networkrailmediacentre.co.uk/news/brighton-main-line-welcomes-back-passengers-after-gbp-67-million-investment-over-9-days); New Civil Engineer (Mar 2022, https://www.newcivilengineer.com/latest/network-rail-engineers-patch-up-leaky-tunnels-rebuild-junction-and-create-underpass-on-brighton-main-line-upgrade-01-03-2022/); Rail Accident Investigation Branch (Jan 2013, https://assets.publishing.service.gov.uk/media/5a81879d40f0b62305b8f727/IR12013_130124_Balcombe.pdf)