About Us

Island Division

The Island Division is responsible for geotechnical control of all building developments and civil engineering works on Hong Kong Island. One of the recent projects that requires high professional and technical inputs of the Division is the construction of Central-Wan Chai Bypass (CWB) mined tunnel underneath ex-Wan Chai Public Cargo Working Areas, the Cross Harbour Tunnel (CHT) approach section and Causeway Bay Typhoon Shelter. The CWB mined tunnel consists of three closely spaced road tunnels: the 3-lane Westbound (WB) and Eastbound (EB) tunnels and the 2-lane Slip Road 8 (SR8) tunnel. The mined tunnel is about 11 m high, 153 m long and has a combined span of approximately 50 m. The geotechnical works of the project comprise construction of a “two-pass lining” for the mined tunnel. The first pass temporary tunnel supports are installed concurrently with the multiple headings for the large span tunnel excavation, and the second pass permanent undrained tunnel linings of cast-in-place reinforcement concrete are installed subsequent to the completion of excavation.

Protection measures for tunneling beneath the CHT structure are provided prior to excavation. Other major geotechnical works of the project include temporary reclamation and construction of cut and cover tunnels to depths over 40 m at the east and west of the mined tunnel.

Excavation of EB Tunnel (Outer Bound) and SR8 Tunnel
Excavation of EB Tunnel (Outer Bound) and SR8 Tunnel
Excavation of EB Tunnel (Inner Bound)
Excavation of EB Tunnel (Inner Bound)
Top Heading of EB Tunnel (Outer Bound)
Top Heading of EB Tunnel (Outer Bound)
Permanent lining of SR8 Tunnel Completed
Permanent lining of SR8 Tunnel Completed

Completion of Temporary Tunnel Support at Western Portal
Completion of Temporary Tunnel Support at Western Portal

General View of the Site
General View of the Site

Other major projects with substantial geotechnical input from Island Division include:

  • Ocean Park Redevelopment Project
  • Shatin-to-Central Link of MTR
  • South Island Line of MTR

In addition to the above, this division is responsible for carrying out slope maintenance audit to assist maintenance departments to improve their performance in discharging their slope maintenance responsibility. It also manages the system for certification of permanent prestressed ground anchors used in Hong Kong.

If you wish to obtain more information about the work of Island Division or have comments relating to our services, please contact Chief Geotechnical Engineer/Island :

Tel.: (852) 2762 5266
Fax.: (852) 2714 0214
Email: chrischlam@cedd.gov.hk