services. After rectification of defects, subsequent samples proved satisfactory.
10.16. All chemical samples proved satisfactory, although with the importation of water from the Pearl River which is tidal, it was necessary to extend the testing to include salinity checks. The maximum recorded was 536 parts per million as compared with the internationally accepted maximum of 600 parts per million for potable water.
Pumping
10.17. The following table shows the quantities of raw and filtered water pumped in comparison with those for the previous year:
1962-63 1963-64 Decrease Raw Water Million Gallons 26,480 15,020 11,460 Filtered Water Million Gallons 14,398 7,935 6,463 Total Million Gallons 40,778 22,955 17,823Waste Detection
10.18. Due to the short hours of supply and the necessity to avoid charging mains unnecessarily, it was only possible to test seven waste detection areas at the beginning of the year. Subsequent investigations were restricted to the inspection of valves, standpipes, hydrants, etc. and checking valves at the boundaries of supply zones to ensure that restrictions were effective.
New Meters Installed
10.19.
Mainland Island Total 1961-62 2,677 975 3,652 1962-63 8,812 1,511 10,323 1963-64 7,597 324 7,921 Service 81,574 91,897 99,81810.20. 1,883 separate items of work, including 30 orders from other Government departments were carried out. The break-down of the horizontal boring machine resulted in 35 orders being executed under local contracts.
10.21. 44,425 meters were overhauled, representing 45% of all meters in service.
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