w You Kom Tau Treatment Works with a capacity of 0.16 million cubic metres per day to augment the supply to Tsuen Wan and Tsing Yi was completed in 19

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14 w You Kom Tau Treatment Works with a capacity of 0.16 million cubic metres per day to augment the supply to Tsuen Wan and Tsing Yi was completed in The Sheung Shui Treatment Works with a capacity of 0.1 million cubic metres per day was commissioned in 1986 for the supply to the Sheung Shui/Fanling New Town. A small treatment works with a capacity of cubic metres per day was built in 1989 at Cheung Sha for southern Lantau Island. The Stage I of the Au Tau Treatment Works with a capacity of million cubic metres per day was completed in 1992 increasing the supply to Tuen Mun, Yuen Long and Tin Shui Wai New Towns. Stage II works bringing the total capacity to 0.33 million cubic metres is under construction. Sheung Shui and You Kom Tau Treatment Works are also undergoing expansion to uprate their capacities to 0.2 and 0.25 million cubic metres per day respectively. Perhaps the most significant of the new projects is the Pak Kong Treatment Works located at the southern end of the eastern route in Sai Kung. Completed in 1992, the plant with a capacity of 0.8 million cubic metres per day is the second largest in Hong Kong. In addition to meeting local demand and supplying the Tseung Kwan O New Town which has a projected population of , the plant also relieves the demand on the Sha Tin Treatment Works which supplies a major part of Hong Kong Island and Kowloon in addition to the Sha Tin New Town. Supply to the New Airport In October 1989, the Government decided to construct a new airport at Chek Lap Kok together with associated residential, industrial and port developments on North Lantau. As a much longer lead time is required to provide a permanent water supply system, a temporary system has been built to meet the requirement of the construction activities for the new airport and other infrastructural projects. This $60-million temporary system was commissioned in The existing fresh water systems on South Lantau the Shek Pik Reservoir and the Silvermine Bay Treatment Works have little spare capacity, after supplying the western part of Hong Kong Island and the outlying islands. It is therefore necessary to bring in water from outside Lantau Island in order to provide a permanent water supply to North Lantau. An aqueduct will be constructed for transferring raw water from Tai Lam Chung Reservoir to feed a new treatment works near Siu Ho Wan together with the associated water transfer and distribution systems. The permanent water supply system with an ultimate capacity of 0.3 million cubic metres per day is being implemented in stages, the first stage to be substantially completed by 1996 at a cost of $1 700 million. This stage comprises a new treatment works, a service reservoir, three pumping stations, about six kilometres of tunnel and about 23 kilometres of submarine and land pipes to provide a capacity of 0.15 million cubic metres per day. The remaining stage valued at $1 500 million is programmed to be carried out in the 2000's. 11

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18 Corrigendum P. 15 (line 2 in paragraph 3) with a combined capacity of 3.53 (NOT 3.73) million cubic metres per day.

19 Treatment Works By 1939, with the exception of the Shouson Hill area, all water on the Island and in the Kowloon urban area was filtered. The original filters were all of the slow sand type, requiring large areas of level ground, which is scarce in Hong Kong. The Eastern Treatment Works built in 1949, for instance, was situated below Tai Hang Road near Jardine's Lookout. It occupied more than 1.2 hectares and had to be formed at two levels with expensive retaining walls. In the early days, the difficulty in finding suitable sites on the Hong Kong Island resulted in a system of separate small filters spacing out along the hillside at Bowen Road, the Albany and the Jardine's Lookout, interconnected by a conduit rather than one single filtration plant. Since these early beginnings, many more treatment plants have been built and by end there were 19 with a combined capacity of 3.73 million cubic metres per day. The Water Treatment Process Raw water comes either directly from China or from one of the storage reservoirs by gravity or via pumps and goes through large diameter pipelines and tunnels to the treatment works. In the treatment works the water first passes through the clarifiers or accelators which are used for settlement, forming the first stage of the water treatment process. To enable large quantities of water to be treated efficiently in a compact plant, sulphate of alumina is added to the incoming water to assist the suspended solids to coagulate into large particles which settle on the floor of the clarifiers in the form of sludge. The sludge is collected, thickened and dumped as waste. The water goes from the clarifiers to the filtration plant where more finely divided suspensions are retained on sand filters when the water passes through the filter media to clear water tanks. Colour and turbidity in water, which are normally caused by solids in suspension, are removed by the filtering process. Thus the filtered water is clear, but it is acidic because of the sulphate of alumina which has been added. Hydrated lime is used to neutralise this acidity and to give the water a slightly alkaline characteristic to reduce corrosion of water pipes and fittings. The water is dosed with chlorine in solution for disinfection and a fluoride compound is added for dental care. After these processes, the water meets the required standard and is ready for distribution to the consumers. Each filter bed in a treatment plant has to be cleaned regularly by passing air and water sequentially through the bed in a reverse direction to the normal flow of water. Wash water at the principal stations is collected after use and channelled back into the main inlet point to mix with the raw water for processing by the clarifiers. This cycle continues, thus reducing the quantity of water running to waste. At Sha Tin Treatment Works, for example, the amount of wash water used ranges from to cubic metres a day-approximately one per cent of the inflow to the plant. 15

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32 w The Department and the Customers Organisation The principal function of the Water Supplies Department is to plan water resources and to design, construct, maintain and operate water supply systems in order to provide a satisfactory supply to meet the demands of the territory. The powers necessary for the operation of the waterworks are contained in the Waterworks Ordinance. The department is headed by the Director of Water Supplies, who is the "Water Authority'. He is responsible for the overall control and coordination of all government activities concerning the provision of potable and flushing supplies throughout the territory. The Deputy Director of Water Supplies is responsible for the day-to-day business of the department and for the operations needed to enable the functions of the Director of Water Supplies to be carried out. The Director and the Deputy Director are supported by six Assistant Directors, the Business Manager and the Departmental Secretary. They head the operating branches, accounts division and the secretarial section, each having intimate knowledge of his/her own sphere of operations, and being responsible to the Deputy Director for the effective management of the department. The establishment by the end of 1992 comprises nearly employees, with about 300 professional officers, technical officers, 800 general grades (accounting, executive, clerical and secretarial) staff, and about skilled, semi-skilled and junior staff. Customer Relations and Services The Water Supplies Department is not only a government department but also a public utility. Hence in addition to its normal operational and developmental functions, the department has also made rapid strides in improving its customer relations. Due to the fast growth in the number of registered consumers (1.9 million as at 1992) and growing consumer awareness, the need to improve the channels of communication between the public and the department has become more essential. The department now handles approximately about one million enquiries a year, which almost doubles the figure five years ago. Customer enquiries and complaints usually come under two major categories-account oriented or technical oriented. The former includes issues like high water bills and change of consumership while the latter is mostly related to poor water quality and interruption of supply. A manned telephone enquiry centre handles account oriented enquiries during office hours. It is also installed with a 24-hour enquiry hotline to provide recorded messages on common topics such as how to deal with a high water bill, how to change a consumer title and how to obtain a refund of water deposit. On the technical side, two complaint centres - one in Hong Kong (Java Road Depot) and the other in Kowloon (Argyle Street Depot) - have been established to accept calls regarding poor water supply and other problems. These centres are manned 24 hours a day. 28

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