UK's Network Rail Completes Waterproofing and Reinforcement Works on Four Railway Tunnels in Liverpool

en.Wedoany.com Reported - On November 7, UK's Network Rail completed reinforcement and waterproofing works on four underground tunnels on the Merseyrail Northern Line in Liverpool, with the Northern Line resuming normal operations after a 27-day construction closure. The project involved an investment of £3.5 million, covering the underground railway section between Brunswick Station and Liverpool Central Station. In addition to tunnel structural repairs, the third-rail power supply control systems on the Northern Line and the Wirral Line were also upgraded simultaneously.

The works commenced on October 11, 2026, with more than 50 construction workers participating in the implementation. All four tunnels were built during the Victorian era and have long served the Merseyrail trains traveling to and from Liverpool city center. As water seepage through the underground tunnel walls could affect the operation of the third-rail power supply system, the project focused on repairing aging structures, preventing water from entering the tunnels, and improving drainage conditions in the track area.

The tunnel structural works began with the removal of 92 square meters of aged concrete, followed by concrete repairs. The waterproofing works adopted a drilled grouting process, with workers drilling 6,500 holes into the tunnel walls and injecting waterproof resin into the wall interiors, which cured to form a waterproof barrier. A total of 1,688 square meters of tunnel wall waterproofing was completed.

Drainage facilities were also upgraded accordingly. Workers drilled 115 weep holes into the tunnel walls to channel water seeping into the walls to the track bed drainage system, reducing the impact of standing water on the track structure and power supply facilities. The above waterproofing and drainage measures primarily address the long-term water seepage problem in the underground tunnels, preventing water from entering the third-rail power supply area and causing electrical faults.

In addition to the tunnel civil engineering works, Network Rail also used this closure window to upgrade the power supply control systems on the Merseyrail Northern Line and Wirral Line. The modifications involved third-rail power supply sectioning control equipment and related control systems, enabling maintenance personnel to remotely isolate power to designated sections more quickly, narrowing the scope of power outages during planned maintenance or unexpected faults, and improving equipment maintenance conditions.

After 27 days of intensive construction, the Merseyrail Northern Line resumed operations on November 7, with trains running again between Hunts Cross and Liverpool city center. During the closure, Network Rail and Merseyrail arranged replacement buses and adjusted train service plans to maintain public transport connections for the affected sections.