Location

Hong Kong

Client

Drainage Services Department, HKSAR Government

Contract Value

HK$4 billion

Construction Period

2009 Q3 - 2013 Q4

The contract, which forms a main part of the Harbour Area Treatment Scheme (HATS), comprises the construction of three deep tunnels to collect and convey the preliminarily treated sewage along the north of Hong Kong Island and under the Victoria Harbour to Stonecutters Island for chemical treatment. It also involves the construction of eight shafts.

The three tunnels, totalling 12 kilometres in length and up to 165 metres in depth, were constructed using drill and blast techniques.

To enhance safety of the project, a specialised Tunnel Personnel Tracking System was developed. Electrically powered equipment was also selected for the tunnelling operation to enhance the working environment. Other advanced equipment used on the project included computerised drilling jumbos and computerised grouting injection systems.