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PUBLIC WORKS AND UTILITIES
a pier for the cattle quarantine depot at Tsing Yi, and two public piers at Sai Kung town and Joss House Bay are in progress.
Drainage, Sewage Works and Anti-pollution Projects
Flood protection to urban and rural areas is afforded by stormwater drainage culverts and nullahs. Stormwater drains at Western Reclamation were completed during the year while similar works at Cheung Sha Wan and Chai Wan commenced.
Sewage from developed areas is, in general, collected by separate sewage systems and subjected to various modes of treatment depending on the quality of effluent acceptable in the waters where it is discharged. Sewage from rural areas where sewage systems are not provided is often disposed of through separate sewage treatment facilities such as septic tanks, Imhoff tanks and package sewage treatment plants. To provide for the efficient treatment and disposal of sewage, progress was made on the construction of a screening plant in Central District and on treatment plants at Yuen Long and Tai Po, while the year saw the completion of pumping stations at Hung Hom and Tsuen Wan, treatment plants at Tai O, and the first stages of works at Sha Tin and Tuen Mun and for a submarine outfall off the airport runway. Construction commenced on a pumping station in Mong Kok and a submarine outfall at Kwun Tong. Progress was maintained on the detailed design of the first stage of treatment works for northwest Kowloon.
Throughout the year, extensive monitoring of Hong Kong waters continued to determine the state and trend of the quality of territorial waters and to evaluate the effective- ness of existing sewage treatment and disposal facilities in meeting formulated water quality objectives. Recommendations for the implementation of improvement works were submitted. A data report summarising the long term monitoring results up to early 1982 was completed. A preliminary survey on factory discharges was carried out in Tai Po and Sha Tin areas for the implementation of the Water Pollution Control Ordinance over the Tolo Harbour and Channel control zone.
A programme of solid waste management was maintained with about 1.6 million tonnes of solid waste being treated and disposed of in four controlled tipping sites at Ma Yau Tong, Siu Lang Shui, Shuen Wan and Junk Bay. A comprehensive study of disposal requirements for toxic, hazardous and difficult wastes was completed by consultants, and the formulation of plans for future control and management of the disposal of such wastes proceeded.
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To assist waste management planners, consultants were engaged to develop computerised forecasts of future demands for waste disposal facilities and to evaluate alternative waste disposal strategies and methods. Several locations were identified as potential sites for future large capacity waste disposal facilities to deal with growing waste disposal needs, and plans were prepared for comprehensive environmental, operational and economic assessment of the sites.
Water Supplies
Hong Kong was still under water restrictions as it entered 1982, although subsequent heavy rainfall after the previous two years of below-average rainfall - and further increases in the supply from China, improved the water storage situation significantly and allowed full supply to be restored later in the year.
Water restrictions had been imposed in October 1981. On January 1, 1982, a 10-hours- a-day supply was being maintained which was eased on May 5 with the introduction of a 16-hours-a-day supply. The easing of restrictions and their ultimate lifting on June 1 was