The Drainage Services Department has adopted an innovative interception concept in constructing HKWDT, the largest scale drainage tunnel in Hong Kong. It was completed in August 2012. The tunnel is 10.7km long, from Tai Hang to Cyberport, with diameter up to 7.3m and 34 intakes. It intercepts stormwater from uphill at Mid-Levels for direct discharge to the sea, thus alleviating the flooding risk in the downstream urban areas of northern Hong Kong. This concept avoids road opening in congested roads and considerably reduce the disturbance to the public and traffic.
HKWDT embodies many innovative approaches and technical firsts in Hong Kong’s construction industry including the first to systematically use raise boring method to excavate underground dropshafts. This can greatly reduce the dust and noise nuisance.
