Tuen Mun-Chek Lap Kok Link – Northern Connection Sub-sea Tunnel Section

Completed Project

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As Hong Kong’s deepest, longest and largest sub-sea road tunnel, this project has the largest contract sum ever awarded in Hong Kong, a reflection of the project’s scale and complexity.

This dual two-lane sub-sea tunnel runs between the western New Territories and Lantau Island. The world’s largest Tunnel Boring Machine (TBM) of 17.6 metres in diameter and two identical mix-shield TBMs of 14 metres in diameter were used to construct the road tunnels. These state-of-the-art machineries were equipped with in-house innovations – namely MOBYDIC, SNAKE and TELEMACH – which enabled real-time geological mapping of rock faces, and robotic detection of damaged components on the cutter head to reduce manual inspections under hyperbaric conditions.

Working under a compressed-air environment was the key challenge of this project. The project team had proposed to use a saturation technique for maintenance works on the TBMs’ cutter heads, which maximised the health and safety of workers, while also enhancing work efficiency.

Sustainable measures were in place during and after construction, such as recycling excavated materials from the north reclamation as backfilling of the launch shaft or returning it as public fill. The two ventilation buildings attained a Hong Kong BEAM Plus Gold rating upon completion. Wind turbines also be built in both buildings for renewable power generation.

Client Highways Department, Hong Kong Government
Project Design and construction of a dual two-lane sub-sea tunnel of about 5km and reclamation of about 16.5 hectares of land
World’s largest TBM 17.6m in diameter
HK’s deepest sub-sea road tunnels up to 60m below sea level
HK’s longest sub-sea road tunnels Approximately 5km long x 2 tubes
HK’s greatest no. of cross passages for road tunnels 52


Construction period 2013 – 2020