A river is not simply a unidirectional flow of water from the sources to the estuary. On the contrary, it comprises all its branches flowing from the sources into the ocean, as well as its network of interconnections with the groundwater system. In addition, the land of the whole catchment area and the river itself are intertwined physically, chemically and ecologically. The river course and estuary, together with the land of the river basin, form a whole river.
If we ignore the fact that a river and its land are closely linked and focus only on the channels when river problems arise, we will not be able to effectively eradicate their root causes. For example, when we see a decline in water quality, it may not be caused only by polluted water being discharged directly into the river, but also due to the removal of vegetation that prevents the land from effectively filtering the pollutants. In the event of worsened floods, it may not be because the river is narrower than before but because the extensive development of the river basin increases the amount of impermeable surfaces that do not absorb the excess surface runoff during heavy rain storms.
A river and its basin environment are closely related. Thus the conservation of a river must include proper management of its basin. This means appropriate planning of land uses plus stronger enforcement of the law to stop environmentally damaging acts. For instance, a large area of agricultural land in Shek Lau Po Village has become an open storage yard and poorly managed vehicle workshops on the river banks often discharge polluted water directly into the river. Such activities within the basin must be halted as soon as possible. Also, illegally widened roads must be restored and vehicles carrying garbage, construction and demolition materials must be forbidden to use sections of the Tung Chung Road within Tung Chung River Valley. In the long run, the government could acquire private lands in the valley and limit land uses to those compatible with the conservation intention to adequately protect Tung Chung River.
Future extension of Tung Chung New Town must be done according to the “river basin management” principles, taking Tung Chung River and its entire basin into account in its planning to preserve "the whole river” so that Tung Chung River can continue to provide its ecosystem services. To achieve the above, the following principles must be followed:
Most of Tung Chung River is still in its natural state and has not been extensively modified. With the “river basin management” principles upheld, it has the potential to become the new model for urban planning in Hong Kong, avoiding the fate of other rivers that were simply seen as drainage channels. To avoid the various environmental problems of the old model, we have the following suggestions: