RAW WATER:
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Total number of samples examined.... 145
Number showing B. Coli present in 50 c.c. or less...... 145 = 100%
FILTERED WATER-UNCHLORINATED:
Total number of samples examined... 147
Number showing B. Coli present in 50 c.c. or less...... 147 = 100%
FILTERED & CHLORINATED WATER (At Service Reservoirs):
Total number of samples examined... 146
Number showing B. Coli absent in 50 c.c. 130 89.05%
present in 50 c.c. 13 8.91%
in 25 c.c. 1 0.68%
in 10 c.c. or less..... 2 1.36%
TAP WATER--FILTERED & CHLORINATED:
Total number of samples examined...... 466
Number showing B. Coli absent in 100 c.c. 186 39.91%
present in 100 c.c. 27 5.80%
absent in 50 c.c. 160 34.33%
present in 50 c.c. 54 11.59%
in 33 c.c. 2 0.43%
in 25 c.c. 7 1.50%
in 16.6 c.c. 4 0.86%
in 10 c.c. or less 26 5.58%
162. The standard of purity was raised to B. Coli absent in 100 c.c. on 17th October, 1946. The supply was treated with 588 lbs. of liquid chlorine and 182,250 lbs. of chloride of lime which is equivalent to an average admixture of free chlorine of about 1.1 parts per million. 538 samples of filtered water were analysed by the Government Chemist and in all cases the report was "Satisfactory".
163. Waste Detection.
13,162 routine inspections of house services were carried out and 1,564 notices to repair or alter defective services were served on members of the Public. 745 taps were rewashered free of charge. 2,956 fittings to be used on inside services by licensed plumbers were tested and stamped. No tests were made by the Deacon Waste Detection meters owing to the loss of all plans showing the layout of the waste detection areas, the lack of staff, and the absence of certain equipment which did not arrive until late in the year.
* Most of these bad samples were from Shaukiwan district where local pollution occurred due to bomb damage to service piping. This was difficult to trace and involved the relaying of a considerable length of subsidiary piping. This work had not been completed by the end of the year.