Catchwater Divertig the River

The broad Kam Tin River basin has formed an extensive and fertile alluvial plain in the Kam Tin area, which and attracted people to settle and farm. By the 1960s, urbanization had resulted in significantly higher demand for drinking water. A catchwater was built from Shek Kong to Tsat To River, diverting all upstream tributaries of Kam Tin River in the southern drainage basin to Tai Lam Chung Reservoir. As a result, water flow into Kam Tin River was drastically reduced, harming the river ecology and altering the hydrology.


Tai Lam Catchwater


The riverbed under Tai Lam Catchwater is dry

Water Pollution

Recently, agricultural production has fallen, and people have abandoned the farmland around Pat Heung, Kam Tin and Shek Kong. Only few fields and pig remain; large areas were transformed into storage facilities and car parks. The domestic waste, livestock waste and industrial wastewater from extensive areas all enter the middle course of Kam Tin River. Solid waste, grease, faeces, chemicals and food waste all pollute the river, seriously affecting the river ecology.


Wastes pile up besides Kam Tin River

Water pollution is severe at the middle course of Kam Tin River

Exotic Fish Species

From the 1960s', there were many fishpond operating at the middle to the lower course of Kam Tin River, the fish species kept are mainly exotic, e.g. Big Head Carps (Aristichthys nobilis), Grass Carps (Ctenopharyngodon idellus) and Tilapias (Tilapia sp.). These exotic fishes, with higher adaptability, escaped from the fishponds expelled native species from the Kam Tin River, further modifying the river ecology.

Abandoned fishpond at Lut Chau

Hillfire

Hillfires frequently occur at the east and north watershed of Kam Tin River – Tai To Yan and Kai Kung Leng. The soil loses moisture, and without the vegetation it becomes readily eroded, thus, landslides are likely to occur and the landscape has been modified. Ash deposited in the rivers will deteriorate the water quality.

The river valley was dried up by the hillfire

Channelization

With the increasing demand for land, areas near the Kam Tin River basin were developed. To avoid flooding affecting residents, the government implemented large river training projects along Kam Tin River; starting along the middle course of Kam Tin River, the river channel was widen and straightened. The government opted to create a new drainage channel by breaking through the fishponds in Nam Sang Wai that merged with Shan Pui River before entering inner Deep Bay.

Because of river channelization, the natural landscape of Kam Tin River was lost; likewise, the fish ponds, wetlands and mangroves of the lower course were also lost, destroying habitats of animals and plants. Luckily, many ecological compensatory measures were implemented. Many mangroves were planted at the new channel of the lower course of Kam Tin River, and some estuarine animals such as the Bluespotted Mudskippers (Boleophthalmus pectinirostris) and fiddler crabs (Uca sp.). During winter, many migratory birds come here to feed.

The channelized Kam Tin River at Pat Heung
The planted mangrove at the river mouth of Kam Tin River

Copyright 2010 by Green Power All rights reserved.