Hydrological Section
8.41. The principal function of this Section is to collect and study hydrological data from catchments in the Colony in order that accurate assessments of water yield may be made for any part of the Colony. Observations were taken at 117 rain gauging stations, 15 stream gauging stations, seven reservoir overflow stations and two evaporation stations. Construction of a new type of weir, particularly suitable for flow measurement in steep stream courses carrying large quantities of silt, was completed at a stream course in the Tai Lam Chung reservoir catchment. Construction was started on a weir of the same type at Nim Wan in order to provide information on yields in the north-western part of the Colony.
8.42. A report 'Gross Yield of Hong Kong Reservoirs' was completed, providing observed and extended yield sequences suitable for operation and regulation studies. A draft report detailing a 'design flood' for Hong Kong was completed and, as an extension of this work, a flood study was made on the spillway capacity at Shek Pik reservoir.
Water Resources Survey Section
8.43. The Water Resources Survey is being carried out in conjunction with Messrs. Binnie & Partners and the terms of reference have been extended to include a detailed study of desalination of sea water.
8.44. Drafts for the main final report and technical notes on water demand, waste and waste detection, cost of water schemes, geology and ground-water, manual regulation study and waterworks statistics were completed. The writing of a new computer programme for the operations study was put in hand to assess the balancing effect and to study the operation of Lower Shing Mun reservoir.
Planning Survey Section
8.45. Investigations were made for the improvement of supplies to the western mid-level urban development of Hong Kong and to the Aberdeen area and an assessment was made of trunk main requirements for the distribution of Plover Cove water on Hong Kong Island. Proposals were agreed for supplies to areas along the Tai Po/Ting Kok road, Cheung Chau Island and proposed Government Low Cost Housing estates in Tsuen Wan/Kwai Chung. Investigations were put in hand for the provision of Government mains supplies to military establishments and villages in the New Territories. During the water shortage of 1967, temporary
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