ENG-1955 — Page 192

Chapter 14: Public Utilities and Public Works

Waterworks

The supply of water to the Colony is the responsibility of the Public Works Department of the Government.

Owing to the absence of large rivers, or other sources of supply, the Colony is entirely dependent for its water on rain, most of which falls during the summer when the south- west monsoon blows and occasional typhoons are experienced. The water is impounded in 13 storage reservoirs which have a total capacity of 5,970,000,000 gallons. These reservoirs, which are situated on Hong Kong Island and in the New Territories, normally fill up completely during the wet season, but the storage, together with the dry-weather yield of streams, is inadequate for the demands of a growing population and increasing development. Severe restrictions on the hours during which water is available to the public have to be imposed every dry season. Of the maximum possible storage, only 2,362,000,000 gallons can be held on the Island. The Jubilee Reservoir, situated not far from Tsun Wan in the New Territories, is at present the Colony's largest, holding 2,921,000,000 gallons, with a dam 275 feet high, one of the tallest in any colonial territory. It will, however, soon take second place to the new reservoir now under construction at Tai Lam Chung which, when completed, will impound at least 4,500,000,000 gallons. In addition to these works, Hong Kong possesses a system of catchwaters 35 miles long. These channels run along the mid-levels of various hillsides, inter- cepting streams and water courses, and conveying their water into the various storage reservoirs.

About one-third of the Island's consumption has to be met from New Territories reservoirs. This water is conveyed across the harbour in two 21-inch diameter concrete-lined steel submarine pipes. On account of the hilly nature of the Island a large proportion of the water has to be pumped, and in some areas re-pumped, necessitating numerous pumping stations and service reservoirs. The water supply to the Island and the urban area of Kowloon is filtered and sterilized by chemical treatment, and a high standard of purity is maintained.