LAND, PUBLIC WORKS AND UTILITIES
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seabed pits at East Sha Chau, which also houses an empty marine sand borrow pit for contained disposal of contaminated mud.
The Public Filling Sub-Committee of the FMC co-ordinated the public filling activities for the beneficial use of construction and demolition (C&D) materials. In 1999, about 5.9 million cubic metres of pubic fill were used in reclamations. A study was conducted on the establishment of C&D material sorting facilities with. a view to improving the quality of public fill and to minimise the amount of such materials to be disposed of at landfills. As a result, the first sorting facility will begin operation in 2000. The study also recommended the establishment of a network of public filling barging points in the urban area in order to minimise impacts arising from long haulage to public filling areas by road. Three temporary public filling barging points located at the waterfront of Quarry Bay, Sai Ying Pun and Tseung Kwan O Area 137 respectively were put into operation in December.
In connection with the management of Hong Kong's fill resources and mud disposal capacity, the CED, on behalf of the FMC, continued to undertake a series of geotechnical, environmental and ecological studies and monitoring to examine the effects of the dredging and disposal activities, and to investigate possible ways to avoid or minimise adverse effects on the marine environment.
Hydraulic Studies
Large reclamation projects may affect the flow of water, sediment transport and wave activity in the harbour. To minimise any adverse effects, the Civil Engineering Department employs sophisticated hydraulic models to analyse the likely effects of proposed schemes to ensure that they are within acceptable limits. The models are used for reclamation layout planning, design of marine structures, waterway studies and assessment of future maintenance dredging requirements. The models comprise computer-based mathematical models and a large physical model housed in the Harbour Laboratory at Tuen Mun.
A number of hydraulic studies have been carried out to investigate the impact of major coastal engineering projects. These major projects included the Green Island Reclamation, Tonggu Waterway, Siu Lam Typhoon Shelter, and Tang Lung Chau Dangerous Goods Anchorage. In view of the deterioration in the wave condition in the inner part of the Victoria Harbour, a new type of seawall capable of absorbing wave energy has been developed, and is being built at the new seafront of the West Kowloon Reclamation for trial purposes.
Water Supplies
Water from Guangdong
Guangdong rivers are Hong Kong's major source of raw water. This arrangement dates from 1960, when a scheme was formulated for receiving a piped supply of 22.7 million cubic metres a year.
In 1989, a long-term agreement was concluded with the Guangdong Provincial Authority for a reliable water supply. As a result of the expected decrease in demand for raw water from Guangdong due to heavy rainfall in recent years and the declining demand from industry, an agreement was reached with the Guangdong Provincial