LAND, PUBLIC WORKS AND UTILITIES
and a sewer tunnel of 3.2-metre diameter and 7.5 kilometres in length under Tsz Wan Shan. The sewer tunnel was broken through in June 1992 and construction for the whole of the works is scheduled for completion in two stages in 1993 and 1995.
Other projects which are being implemented under this first category include the construction of a sewage screening plant to serve a population of 1.2 million in the Tsuen Wan and Kwai Chung area, a secondary sewage treatment plant to serve the rural public housing in Peng Chau and the upgrading and extending of the existing Tseung Kwan O sewage treatment plant. In late 1992, the government completed the construction of the Ha Tsuen sewage pumping station, the San Wai sewage treatment works, and the rising main between them, which together form part of the North West New Territories Sewerage Scheme. The extension of Yuen Long sewage treatment works was also completed in 1992.
Under the second category, projects are being implemented to improve the sewage collection, treatment and disposal facilities in the areas of Tsuen Wan, Kwai Chung, Tsing Yi, Yuen Long, Kam Tin and Port Shelter. Design works are being carried out for these projects and construction works are scheduled for commencement either in 1993 or 1994. In East Kowloon and the southern district of Hong Kong Island, works to improve sewage disposal facilities have already started.
Under the third category, engineering feasibility studies were carried out to study the details for the implementation of the strategic sewage disposal scheme. The studies have provided useful information for the design of this massive sewerage scheme involving a system of deep sewer tunnels.
Stormwater drainage
For stormwater drainage, the Drainage Services Department is responsible for the formulation of strategies, standards, project planning and implementation. Past records indicate that the North and North-West New Territories are particularly vulnerable to flooding. Further to an initial territory-wide study carried out by consultants in 1989 to review rainfall, stream flow and flooding prediction, the department has commissioned another study with the aim of drawing up basin management plans for the main rivers in the North and North-West New Territories and to examine in more detail what local flood mitigation measures can be taken. In addition, pamphlets giving advice on what to do and what not to do in a flooding situation have been widely distributed through District Offices to people living in flood-prone areas.
Among structural measures, which the government has already put in hand, are the construction of main drainage channels in the North-West New Territories flood plains and local works to protect low-lying villages. Construction of 6.5 kilometres of channels for the Tin Shui Wai hinterland has been completed and design has already been put in hand for another 14 kilometres of channels in Yuen Long, Kam Tin and Ngau Tam Mei with a view to starting work on site in 1993. As an associated measure, flood water pumping systems have also been constructed to mitigate the impact of flooding in low lying villages. About a dozen, mainly in the New Territories, are currently in operation and more are planned for construction in the future.
The ground work for the creation of a Land Drainage Ordinance has been completed and a Land Drainage Bill is being prepared. The bill, when enacted, will empower the government to access and maintain important watercourses running through private land, or through government land but surrounded by private land.
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