ENG-1991 — Page 264

LAND, PUBLIC WORKS AND UTILITIES

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The office continues to upgrade the level of services available for land and marine ground investigations and geophysical surveys. Ground penetrating radar was among the new technologies examined during the year. A series of marine investigations was completed to enable an assessment to be made of the reserves of marine sand to be found in Hong Kong waters for use in planned reclamation works.

Water Supplies

Water from China

The supply of water from China is now the major single source of supply for Hong Kong and it is from this source that all future increases in demand will be met. This dates back to 1960 when a scheme was first formulated for receiving a piped supply of 22.7 million cubic metres a year. Today, the annual supply from China stipulated under the agreement has increased to 570 million cubic metres and this will continue to increase in stages to 660 million cubic metres by 1994-5. Apart from the fixed quantities of supply stipulated in the agreements, there are provisions to purchase additional supplies from China in years of low rainfall in Hong Kong. In 1991, the quantity of the additional supply was 140 million cubic metres. The concept of seeking a supply from China and steps taken by the Water Supplies Department of Hong Kong to realise such a goal have brought about radical changes to the history of water supplies in the territory.

Following the agreement reached with the Chinese Authority in December 1989 to increase the China water supply to a maximum of 1 100 million cubic metres per year to cope with the anticipated water demands of Hong Kong beyond 1994 and into the turn of the next century, a conceptual plan was developed for the necessary works to receive and distribute the additional supply. The works will be implemented in stages with the Stage I works to be completed by end-1994. The Stage I works include some 22 kilometres of large-diameter delivery pipes, new pumping stations at Muk Wu, Tai Po Tau, Au Tau and Sai O and uprating of an existing pumping station at Tai Mei Tuk. Design work was in an advanced stage by the end of the year with a view to commencing construction by early 1992.

Water Works

Full supply was maintained throughout the year. At the beginning of 1991, there were 179 million cubic metres of water in storage, compared with 243 million cubic metres at the start of 1990. The combined storage of Hong Kong's largest reservoirs, High Island and Plover Cove, was 137 million cubic metres. Rainfall for the year was 1 639 millimetres compared with the average of 2 214 millimetres. Water piped from China during the year totalled 701 million cubic metres.

A peak consumption of 2.76 million cubic metres per day was experienced, compared with the 1990 peak of 2.66 million cubic metres. The average daily consumption through- out the year was 2.42 million cubic metres, an increase of 1.3 per cent compared with the 1990 average of 2.39 million cubic metres. The consumption of potable water totalled 884 million cubic metres compared with 873 million cubic metres in 1990. In addition, 123 million cubic metres of salt water for flushing was supplied, compared with 119 million cubic metres in 1990.

With reliable supplies available from China, it was decided by the Executive Council in July 1989 to dispose of the Lok On Pai Desalting Plant. The plant was sold by public