Mar 01

Harbour Area Treatment Scheme Stage 2A - Wah Fu Adit

Harbour Area Treatment Scheme Stage 2A - Wah Fu Adit

The Company has been awarded the contract by Leighton-LNS JV to supply experienced supervision and skilled workforce and is currently mobilizing the personnel to execute the production phase, by drill and blast, for underground scope of works for the project at the Wah Fu Adit that will facilitate an interconnection tunnel between the Wah Fu intermediate PTW and the main sewage exchange tunnel when on line.

The whole contract includes a sewage exchange tunnel from Aberdeen to Sai Ying Pun on Hong Kong Island. The project is part of the Hong Kong Government's Harbour Area Treatment Scheme (HATS), a world-class sewage treatment project. When the project is finished the harbour basin in Hong Kong will be much cleaner and healthier. The contract includes project planning and driving of 7.5 km tunnel. Furthermore, 5 shafts with lengths from 70 to 120 meters will be constructed. Inside the tunnel, 2 oval pipes with diameters from 1.38 m to 1.65 m shall be cast. About 140 000 m3 of concrete will be used all together. The tunnel is partly below the sea and runs partly below buildings in Hong Kong.

The greatest challenge to this project is driving the tunnel below the large urban city. Very strict requirements have been set for sealing and water tightness of the tunnel being constructed using drill and blast method.

The project has now commenced and should be finished in December 2013.