Drainage improvement works in the urban areas meets a different kind of construction problems. In Hong Kong, most of the utilities such as electric cables, telephone lines, TV cables, gas pipes, water pipes, etc., are all laid underground beneath the public roads and pedestrian footways. Construction of the large-size drainage network will unavoidably induce disruption to the traffic and inconvenience to the public.

Traffic disruption due to road opening works

Drainage improvement works at Nelson Street (PDF format, 261KB)

In view of the disruption caused and the numerous constraints in carrying out road opening works in old urban areas such as the lack of space, traffic and utility diversion problems, innovative improvement options are now being considered under the Stormwater Drainage Master Plan Studies to minimize these effects. The options include the following:

(i) application of no-dig technology to eliminate road opening works;

(ii) provision of underground storage tanks ;

(iii) pumping of flood water from low-lying areas;

(iv) application of tunnel technology.

In the urban West Kowloon areas, drainage improvement works are currently being implemented and estimated to cost HK$4.2 billion.

Drainage Tunnels

Flood Storage Pond