Since its establishment in September 1989, Drainage Services Department has been deploying concerted efforts to relieve the flooding problem in the territory. At that time, serious and frequent flooding was experienced in the low-lying flood plains of the North and Northwest New Territories. To combat the flooding problem, the Department has undertaken a number of consultancy studies and initiated a flood protection programme in the areas.

The programme includes a series of major river training projects that provide the primary drainage network to alleviate the flooding problem by improving the Shenzhen River, Ng Tung River, Shan Pui River and Kam Tin River. Besides, the programme also incorporates a number of flood protection schemes at the low-lying villages. Protective bund is built for enclosing the village area to prevent external flood water from entering into the village, whereas rainwater falling within the village area will be brought over the protective bund by pumping station to the nearby channel.

During the course of the Stormwater Drainage Master Plan Studies, a number of drainage improvement options have been identified for the existing system. These can be categorised as follows:

The choice of improvement options depends upon the characteristics of individual catchment area. We need to take into account of the various constraints such as the configuration of the drainage system, land requirements, environmental consideration, traffic impact, interface with other projects, the location of major utilities and underground structures, etc.

Consequently, we formulated the most cost effective first aid and long term improvement measures to meet the current flood protection standards and future needs. First aid measures were carried out immediately after the study to provide immediate relief to the flooding problem. Long term improvement measure will upgrade and extend the existing drainage system such that after their implementation, the problem of flooding will have generally been resolved.