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03

Jun

2026

Crowborough Tunnel Drainage Renewal

Image representing Crowborough Tunnel Drainage Renewal from ASH Construction Group Ltd

Crowborough Tunnel Drainage Renewal🚧

Another successful possession delivered by the ASH Construction Group Civils team, bringing the Crowborough Tunnel Drainage Renewal project to a successful close in partnership with SRE.

This scheme was designed to address long-standing drainage issues at the country end of the tunnel, improving water management and enhancing the long-term resilience of the railway infrastructure.

Over a series of 27-hour, 52-hour and final 72-hour possessions, the team completed:
🔹 250m of Down Cess drainage excavated to 1.8m depth, including 100m through a challenging 700mm-thick mudstone layer
 🔹 200m of Up Cess drainage excavated to 1.5m depth
 🔹 50m of 6ft drainage installed, including 3 catchpits
 🔹 50m of Up Cess concrete channel drain installed
 🔹 Reprofiled crest drain with a precast headwall and 20m of HDPE trench lining bedded on C10 Gen 1 concrete
 🔹 2 x 7.2m UTX crossings installed using ductile iron pipes due to reduced depth, encased in C30 concrete

Despite challenging ground conditions and high temperatures, the works were delivered safely, with zero incidents, zero operational issues, and a high-quality finish.

Projects like this demonstrate the value of careful planning, strong collaboration and dedicated delivery teams working together to improve the railway for the future.

A huge thank you to SRE, Readypower, and everyone involved in planning and delivering these works. 

Completing the final phase of a project and seeing the positive impact of the finished scheme is always something to be proud of.

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