LAND, PUBLIC WORKS AND UTILITIES
To serve the community, the department has pledged to attend expeditiously to complaints on drainage matters, such as blocked drains, and to promptly process applications for drainage connections for private developments.
Treatment and Disposal of Foul Water
The treatment and disposal of foul water, including domestic sewage and trade and industrial effluent, is based on standards, strategies and programmes drawn up by the Environmental Protection Department.
The projects on foul water disposal are broadly divided into three categories: sewerage or sewage treatment projects which were in the public works programme before the new strategy to combat water pollution evolved; 'sewerage masterplan schemes' which are territory-wide sewerage rehabilitation and improvement projects; and the 'strategic sewage disposal scheme' under the new strategy. The latter is a massive project to collect all the sewage from Hong Kong Island, Kowloon, Tsuen Wan, Kwai Chung and Tseung Kwan O into a deep tunnel, intercepting sewer system that will discharge the sewage, after treatment on Stonecutters Island and Mount Davis, through a long sea outfall into the Dangan Channel, south of Lamma Island.
Under the existing projects category, the largest project in hand was the Tolo Harbour Effluent Export Scheme. This will export the sewage effluent from the Sha Tin and Tai Po sewage treatment works, away from the enclosed Tolo Harbour, into Victoria Harbour, where it can be more satisfactorily diluted through tidal flows. The works comprise sewage pumping stations, rising mains, submarine pipelines and a sewer tunnel, of 3.2-metre in diameter and 7.5 kilometres in length, under Tsz Wan Shan. Stage I of the works between Sha Tin and Victoria Harbour will be completed in 1994 and includes the construction of the sewer tunnel. Stage II of the works between Tai Po and Sha Tin started in late 1992, for completion in mid-1995, and includes the construction of a one-metre diameter, six-kilometre long, steel rising main buried under the seabed of Tolo Harbour.
Other projects underway in this category included the construction of a sewage screening plant to serve a population of 1.2 million in the Tsuen Wan and Kwai Chung area, a sewage pumping station and intercepting sewer at Ap Lei Chau, and a sewerage system at Hung Hom. The Northwest New Territories Sewerage Scheme was commissioned in March.
Under the sewerage masterplan schemes, planning and design work was in hand to improve the sewage collection, treatment and disposal facilities in Tsuen Wan; Kwai Chung and Tsing Yi; North, South and Northwest Kowloon; Central; Western and Wanchai West.
Construction work was underway in the Southern district of Hong Kong Island. In Stanley, a sewage treatment works was being constructed underground, in a cavern, and is due for commissioning in mid-1994, along with the completion of other sewerage rehabilitation and improvement works in the Stanley and Tai Tam areas. The works in Repulse Bay and Shek O are expected to be completed towards the end of 1995. In East Kowloon, a system of new trunk sewers and pumping stations is expected to be completed in early 1994.
Engineering feasibility studies for the implementation of the strategic sewage disposal scheme were completed during the year. Detailed design work for the Principal Collection and Treatment System started and construction is planned to commence in mid-1994.
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