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Quality of Water Leaving Service Reservoirs

Last updated: 23 May 2007

National Standards

Parameter Prescribed Concentration
or Value		 Total Number
of Tests		 Number of
Tests Failed		 % of Tests
Failed		 Number of Reservoirs
with Failures
Coliform bacteria           0/100ml 18,232 86 0.47 55
Escherichia coli 0/100ml 18,232 20 0.11 19
TOTAL   36,464 106 0.29  


Additional European Monitoring Standards

Parameter Prescribed Concentration
or Value		 Total Number
of Tests		 Number of
Tests Failed		 % of Tests
Failed		 Number of Reservoirs
with Failures
Colony counts @ 220C No abnormal
change		 18,225      
Colony counts @ 370C No abnormal
change		 18,225      
Residual disinfectant
(Free chlorine mg/l)		   18,232      
Residual disinfectant
(Total chlorine mg/l)		   18,231      
TOTAL   72,913