1950

# TABLE IV. QUALITY OF WATER. SUMMARY OF WATER ANALYSES FOR 1949/1950.

Type of Water Locality Bacteriological Analyses Total No. of Samples examined Number shewing B. Coli present in:- 10 cc or less 16.6 cc 25 cc 33 cc 50 cc 100 cc

Raw. Island Mainland Total 197 49 246 169 37 206 2 6 18 24 Filtered but Unchlorinated. Island Mainland Total 198 50 248 72 3 75 20 4 24 30 5 35 31 ... 31 Filtered and Chlorinated. At Service Reservoirs. Island Mainland Total 228 50 278 1 Filtered and Chlorinated. From Taps. Island Mainland Total 482 190 672 224 26 250 22 1 23 11 2 13 2 2 1 1

Type of Water Locality Physical & Chemical Analyses Total number of Samples examined Number shewing B. Coli absent in: 22 cc 50 cc Number & Percentage shewing B. Coli absent in 100 cc Number found satisfactory

Raw. Island Mainland Total 96 26 122 8 2 10 20 20 18 Filtered but Unchlorinated. Island Mainland Total 65 65 Filtered and Chlorinated. At Service Reservoirs. Island Mainland Total 122 26 148 122 26 148 105 26 131 104 26 130 50 21 71 (99%) 100% 1 ... 1 Filtered and Chlorinated. From Taps. Island Mainland Total 417 180 597 208 45 253 208 45 253 208 23 231 (87%) (95%) 208 45 253

Standards of purity aimed at:—
Raw water B. Coli absent in 22 cc.
Filtered unchlorinated water B. Coli absent in 50 cc.
Filtered and chlorinated water B. Coli absent in 100 cc.

NOTE: Bad tap samples were found to be due mainly to unclean and corroded storage tanks and inside services. In every case chlorination was carried out and notices served on the consumers concerned to take remedial action.