10.16
The routine maintenance of access roads, catchwaters, control gates, treatment works, pumping stations, staff quarters and depots, and the maintenance and cleaning of service reservoirs continued.
10.17 Three typhoons affected waterworks installations, the last, Typhoon 'Rose', causing some severe damage. During the height of the storm, power supplies were disrupted throughout the Mainland treatment works for several hours. Lengthy delays in the resumption of power supplies to certain installations gave rise to local supply difficulties and in one instance, the Fire Services Department were called upon to assist in providing a temporary pumping system. Further difficulties arose during Typhoon 'Rose' due to the interruption of telephone services and damage to radio aerials at several waterworks installations, as a result of which heavier duty aerials were subsequently ordered for certain key stations.
Operations Sub-Division
10.18 Development of a computer programme for the design of draw-offs from impounding reservoirs to make the best use of the water in storage was in hand, and the development of rules for regulating the resources of the reservoir system to meet certain agreed supply criteria was nearing finalisation. Analysis, by means of a computer, of the 1970 trade consumption sub-divided into supply zones and categories was started. Readings of selected sample meters for per capita consumption study continued but, the data collected was not processed due to shortage of staff. Work commenced on the compilation of annual statistics of water consumption and of the yield and draw-off from impounding reservoirs and consumption in major supply zones. Work was also in hand on a review of the adequacy of pumping installations throughout the system.
10.19 The Hydrological Section continued with the routine maintenance of 123 rain gauging stations, 23 stream and reservoir gauging stations and one evaporation station. In connection with the High Island Water Scheme, weekly readings of water levels at 19 observation wells and 13 low flow weirs also continued.
10.20 Data abstraction and preparation of Volume VII in the series of 'Hong Kong Rainfall and Run-off' continued, and preparatory work for printing a revision of 'Gross Yield of Hong Kong Reservoirs' was in hand.
138