ENG-1988 — Page 378

THE ENVIRONMENT

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Monitoring Programme, carried out by the Royal Observatory, has been set up. In addi- tion to the Control Radiation Laboratory at King's Park, three atmospheric sampling stations have been established at Yuen Ng Fan, Tsim Bei Tsui and Sha Tau Kok to sample atmospheric particulates and deposition as well as to monitor the direct gamma- radiation levels.

The Environmental Protection Department is responsible for water quality monitoring in the sea, at beaches, and in rivers and streams. It runs a comprehensive programme which involves 66 general marine monitoring stations, 54 sediment stations, 23 typhoon shelter stations, 118 sampling points at beaches and 32 manual and six automatic sampling points on nine priority rivers. In addition, special investigations are run for various purposes. The results of the monitoring programme are used to assess the quality of the water against a series of Water Quality Objectives. The objectives for inland waters in the Tolo Harbour and Channel Water Control Zone, and for both marine and inland water in the Southern Water Control Zone, were approved by EPCOM and published in the Government Gazette during the year.

Water quality in Hong Kong's open marine waters was good to very good. However, the water quality in some parts of Victoria Harbour (Kowloon Bay, North-west Kowloon and Rambler Channel near Tsuen Wan), the inner parts of embayments (such as Tolo Harbour, Port Shelter, Junk Bay and Deep Bay) and typhoon shelters was unsatisfactory. Decreasing trends in water quality were observed in some of these blackspots. Red Tides occurred frequently in Tolo Harbour, sometimes killing the fish there. Various control actions have been implemented or are planned to improve the situation.

Inland monitoring showed that many rivers and streams were heavily contaminated with livestock waste, sewage and industrial effluents. In some cases, bacteria counts are dangerously high. These results underlined the urgent need for control of livestock waste and for the provision of more mains sewerage. Improvement in water quality was nōted in some watercourses, mainly due to the clearance of squatter areas, resumption of agricul- tural land for new town development, provision of sewer interceptors to villages and reconnection of unauthorised industrial discharges back to the sewerage system.

All but five of Hong Kong's gazetted (that is, publicly-managed) bathing beaches regularly meet the water quality objectives for beaches and are considered acceptable for swimming. Over the past five years, the beaches on the south side of Hong Kong Island, including Repulse Bay, Stanley and Shek O, have shown a steady trend towards poorer water quality. These are some of Hong Kong's most attractive and popular bathing beaches, and monitoring has clearly demonstrated the need for urgent pollution control measures to keep the water quality within reasonably safe limits. As an aid to determining what those limits should be, the Environmental Protection Department and the Depart- ment of Community Medicine at the University of Hong Kong carried out joint investiga- tions into the link between beach water quality and health in the summers of 1986 and 1987. A total of 25 000 beach-goers at nine popular beaches were interviewed in the second phase of the studies in 1987; at the same time, a total of 900 beach water samples were analysed for 8 000 microbial counts. It was found that the morbidity rates for swimmers were significantly higher than those for non-swimmers. Swimmers at the more polluted beaches would be exposing themselves to a greater risk of contracting skin, ear, respiratory and gastrointestinal illnesses. The swimming-associated gastrointestinal illness rates for the Hong Kong beaches were generally low. As the number of bathers at some local beaches is very great, the total number of illness incidents among the bathers is expected to be very great. When the whole project is completed and the results interpreted, it will be possible to