ENG-1970 — Page 200

PUBLIC WORKS AND UTILITIES

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Summer inflows reduced the salinity of the impounded water in Plover Cove reservoir from 400 parts per million of sodium chloride to 210 parts per million at the abstraction point. This latter figure compares favourably with the normal taste threshold which is in the region of 330 parts per million of sodium chloride. Marked thermal and chemical stratification of the stored water was established during the summer months. However, the overall quality of water remained satisfactory with no serious proliferation of algae or difficulties in treating the water. Further fish stocking was undertaken; a total of 381,000 fish, mainly silver, mud, grass and common carp, were introduced.

With the steady expansion of the Waterworks during recent years computers have been introduced to assist in reservoir opera- tion and control and the processing of hydrological data. The increase in the number of metered connections (119,000 in 1965 to 403,000 in 1970) has made the present semi-manual system of accounting cumbersome and work is in hand to computerise this function. Preliminary consideration is also being given to the possible introduction of automated equipment to monitor and control the Waterworks system.

BUILDINGS

Building costs, which had increased sharply in 1969 due to rising wage rates and higher costs of materials, continued to rise throughout 1970. It is estimated that the general rise in costs over the year was about 40 per cent. In the latter half of the year material costs had started to level off to some extent but wages were still rising, thus causing building costs to rise proportionately. The cause of these increases has been attributed to the continued resurgence of private building in Hong Kong, maintaining a shortage of labour in the industry.

Progress on construction of government buildings generally maintained a steady pace although the programme suffered to some extent with delays and stoppages, mainly due to financial difficulties experienced by certain contractors. Construction and maintenance of new and existing buildings for HBM Ministry of Public Building and Works also progressed steadily. Private