1967-1968

Saline Supply

Normal Supply

(Maximum values in parts per million)

Sodium Chloride (NaCl)...

Total dissolved solids

Total hardness (CaCO3)

8.63. There was a slight change in policy by the Medical & Health Department in regard to the continuing fluoridation of supplies. From 1st May, 1967 the nominal level of fluoride was increased to 1.0 parts per million, but the average level attained was a little lower at 0.83 parts per million due mainly to a world shortage of suitable chemical for dosing.

8.64. A generally satisfactory bacteriological quality of supply throughout the distribution system was achieved, the standard aimed at being absence of coliform organisms in 100ml. Out of 2,175 samples regularly taken from service reservoirs, 98.8% conformed to this standard. Random samples were also taken from consumers' premises and public standpipes and 97.6% of 458 samples from taps connected directly to mains were entirely satisfactory. In the case of 494 samples taken from taps fed from private storage tanks, 92.1% were free from coliform organisms, the larger percentage of substandard samples in this category being mainly due to the dirty condition of some tanks and to defective private services.

8.65. The Section also assisted in the planning and commissioning of new treatment works and with various investigations connected with the Water Resources Survey. The facilities for carrying out water analyses and advising on water quality and treatment matters generally were increasingly utilised. Requests from Government departments, the armed services, commercial firms and the public resulted in the examination of 640 samples, a rise of 43% over the previous year.

CONSULTANTS LIAISON SECTION

Senior Engineer:

NG Lin-hing, B.S.(Calif.), D.I.C., A.M.I.C.E., A.M.I.Struct.E., A.M.I.W.E.

General

8.66. This Section continued its responsibility for liaison with consulting engineers working on water schemes on behalf of the Hong Kong Government. Expenditure on work carried out by consulting engineers during the year amounted to over $53 million.

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