House Service Sub-Division
11.09 The number of additional meters installed was 32,583, a decrease of 42% on the number installed in 1973/74.
11.10 During the period of restrictions from 24th September to 1st November 1974, routine House Service work was delayed as a result of deployment of staff to attend to complaints and to assist the mains gangs in the operation of valves.
SUPPLY DIVISION
Chief Engineer:
NG Lin-hing, B.Sc.(Calif.), D.I.C., C.Eng., M.I.C.E., M.I.Struct.E., M.I.W.E.
WONG Kwok-lai, B.Sc., C.Eng., M.I.C.E. (Acting)
General
LAU Jong-ming, B.Sc., C.Eng., M.I.C.E., M.I.W.E. (Acting)
11.11 The Division comprises a Headworks Sub-Division, responsible for the maintenance and operation of storage reservoirs, intakes, filter stations, trunk mains and service reservoirs, and an Operations Sub-Division, responsible for monitoring output and adequacy of pumping stations, treatment works, service reservoirs and other facilities, for the collection and processing of hydro-logical data for design and record purposes, and for the development of rules for the operation of the multi-reservoir system.
11.12 Rainfall during the normal wet season was low and that recorded by the Royal Observatory from April to September was only 51.2 inches, which is 29.6% below the average for the period. This necessitated the imposition of water restrictions for the first time since 1967. Supply was first reduced to 16 hours a day from 25th September 1974, and this continued until 9th October 1974 when supply was further reduced to 10 hours a day. This arrangement continued until 17th October when water restrictions were temporarily lifted with the approach of Tropical Cyclone 'Carmen' which brought 18.5 inches of rain. Thereafter restrictions were not reimposed, and they were formally removed after the passage of Tropical Cyclone 'Elaine' at the end of the month.
11.13 Desalted water was, for the first time, delivered into the supply system via Tai Lam Chung as a result of the initial trials of the first unit of the plant at Lok On Pai which commenced in March 1975. The total amount produced was 8 million gallons.
11.14 Details of rainfall, storage and consumption are shown in Appendix CC. Rainfall was 10.8% above average but yield, consumption and peak demand decreased by 7.9%, 3.8% and 0.2% respectively when compared with the previous year.
Headworks Sub-Division
11.15 During the normal period of shut-down of Chinese water supply (i.e. 10th August to 1st October 1974), modifications to the draw-off outlet of Muk Wu Balance Tank were carried out to prevent suction of debris into the pump system.
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