• The largest, longest, and deepest sub-sea road tunnels in Hong Kong

  • Our project team awarded “Innovation in Design & Delivery Award” in the NCE (New Civil Engineer) Tunnelling Awards 2018

  • Project team members received the Prevention of Pneumoconiosis Best Practices Award (Excellence Award) and Innovative Improvement Measures Award from the hands of a government official in March 2018

  • Awards received at the Construction Industry Safety Award Scheme 2016/2017 Award Presentation Ceremony: Civil Engineering Sites Category Gold Award, Outstanding Performance in Work-at-height Safety Prize and Safety Teams Category Merit Award

  • Hong Kong’s deepest, largest, and longest sub-sea road tunnels.

  • Entrance of the sub-sea tunnel

  • Cross passages excavated using a pipe jacking technique

  • Excavation of cross passages using mini TBMs – a FIRST in the city

  • The world’s largest TBM – 17.6m in diameter

  • Northern Landfall – Aerial view of reclamation area – August 2018

  • Unique caterpillar-shaped launching shaft was formed using a diaphragm wall, eliminating the use of strutting which maximized both cost and operational efficiencies

  • TBM tunnel breakthrough under water in November 2015

  • World’s largest scale changeover of TBM cutter head from 17.63m to 14m

  • Internal view of Northbound Tunnel – November 2018

  • Northbound Tunnel – Demolition of temporary tunnel lining inside south ventilation shaft – June 2018

  • Northbound Tunnel – Installation of parapet – November 2017

  • Northbound Tunnel – Installation of precast panel for overhead ventilation duct – August 2017

  • Aerial view of Southern Landfall – October 2018

  • Concreting for base slab of South Approach Ramp – November 2018

  • Southern Landfall – General view of cut and cover tunnel – October 2018

  • Southern Landfall – Removal of internal structure installation gantry from Southbound Tunnel – July 2018

  • Internal view of southbound tunnel – May 2018

  • Southbound Tunnel – Installation of precast panel for overhead ventilation duct – January 2017

  • Precast Yard – Storage yard for precast overhead ventilation duct panel – January 2018


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


View Project Website


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 will run 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 are used to construct the road tunnels. These state-of-the-art machineries are equipped with in-house innovations – namely MOBYDIC, SNAKE and TELEMACH – which enable 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 is the key challenge of this project. The project team has proposed to use a saturation technique for maintenance works on the TBMs’ cutter heads, which will maximise the health and safety of workers, while also enhancing work efficiency.

Sustainable measures are 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 will attain a Hong Kong BEAM Plus Gold rating upon completion. Wind turbines will 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


Year of Commencement 2013
Video Tuen Mun-Chek Lap Kok Link