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Quality of Water Leaving Consumers' Taps

Last updated: 29 May 2007

European Directive Standards
National Standards
Additional European Monitoring Requirements

European Directive Standards

Parameter Prescribed Concentration
or Value		 Total
Number of
Tests		 Number of
Tests Failed		 % of
Tests Failed		 Number of
Zones with
Failures
1, 2 dichloroethane 3 µg/l 433 0 0.00 0
Antimony 5 µg Sb/l 506 0 0.00 0
Arsenic 10 µg As/l 506 0 0.00 0
Benzene 1 µg/l 433 0 0.00 0
Benzo(a)pyrene 0.01µg/l 506 0 0.00 0
Boron 1 mg B/l 432 0 0.00 0
Bromate 10 µg BrO3/l 506 13 2.57 7
Cadmium 5 µg Cd/l 506 0 0.00 0
Chromium 50 µg Cr/l 506 0 0.00 0
Copper 2 mg Cu/l 509 0 0.00 0
Cyanide 50 µg CN/l 432 0 0.00 0
Escherichia coli 0/100 ml 5,094 2 0.04 2
Enterococci 0/100 ml 505 0 0.00 0
Fluoride 1.5 mg F/l 431 0 0.00 0
Lead 25 µg Pb/l 506 7 1.38 6
Mercury 1 µg Hg/l 432 0 0.00 0
Nickel 20 µg Ni/l 506 0 0.00 0
Nitrate 50 mg NO3/l 525 0 0.00 0
Nitrite 0.5 mg NO2/l 525 0 0.00 0
Pesticides - Aldrin 0.03 µg/l 432 0 0.00 0
Pesticides - Asulam 0.1 µg/l 432 0 0.00 0
Pesticides - Atrazine 0.1 µg/l 432 0 0.00 0
Pesticides - Azinphos methyl 0.1 µg/l 432 0 0.00 0
Pesticides - Bentazone 0.1 µg/l 432 0 0.00 0
Pesticides - Chlorfenvinphos 0.1 µg/l 432 0 0.00 0
Pesticides - Chlorpropham 0.1 µg/l 432 0 0.00 0
Pesticides - Chlortoluron 0.1 µg/l 432 0 0.00 0
Pesticides - Clopyralid 0.1 µg/l 432 0 0.00 0
Pesticides - Cypermethrum 0.1 µg/l 432 0 0.00 0
Pesticides - Diazinon 0.1 µg/l 432 0 0.00 0
Pesticides - Dicamba 0.1 µg/l 432 0 0.00 0
Pesticides - Dichlorbenil 0.1 µg/l 432 0 0.00 0
Pesticides - Dichlorophen 0.1 µg/l 432 0 0.00 0
Pesticides - Dichlorvos 0.1 µg/l 432 0 0.00 0
Pesticides - Dieldrin 0.03 µg/l 432 0 0.00 0
Pesticides - Diquat 0.1 µg/l 432 0 0.00 0
Pesticides - Diuron 0.1 µg/l 432 0 0.00 0
Pesticides - Endosulphan Total 0.1 µg/l 432 0 0.00 0
Pesticides - Endosulphan-a 0.1 µg/l 432 0 0.00 0
Pesticides - Endosulphan-b 0.1 µg/l 432 0 0.00 0
Pesticides - Endrin 0.1 µg/l 432 0 0.00 0
Pesticides - Fenitrothion 0.1 µg/l 432 0 0.00 0
Pesticides - Fenpropimorph 0.1 µg/l 432 0 0.00 0
Pesticides - Flumethrin 0.1 µg/l 432 0 0.00 0
Pesticides - Flutriafol 0.1 µg/l 432 0 0.00 0
Pesticides - Gamma-HCH 0.1 µg/l 432 0 0.00 0
Pesticides - Glyphosate 0.1 µg/l 432 1 0.23 1
Pesticides - Hexachlorobenzene 0.1 µg/l 432 0 0.00 0
Pesticides - Heptachlor 0.1 µg/l 432 0 0.00 0
Pesticides - Heptachlor Epoxide 0.1 µg/l 432 0 0.00 0
Pesticides - Isoproturon 0.1 µg/l 432 0 0.00 0
Pesticides - Malathion 0.1 µg/l 432 0 0.00 0
Pesticides - MCPA 0.1 µg/l 432 4 0.93 3
Pesticides - Mecoprop 0.1 µg/l 432 1 0.23 1
Pesticides - op-DDT 0.1 µg/l 432 0 0.00 0
Pesticides - pp-DDT 0.1 µg/l 432 0 0.00 0
Pesticides - Parathion 0.1 µg/l 432 0 0.00 0
Pesticides - Pentachlorophenol 0.1 µg/l 432 1 0.23 1
Pesticides - Propetamphos 0.1 µg/l 432 0 0.00 0
Pesticides - Simazine 0.1 µg/l 432 0 0.00 0
Pesticides - Tecnazene 0.1 µg/l 432 0 0.00 0
Pesticides - Terbutryne 0.1 µg/l 432 0 0.00 0
Pesticides - Trifluralin 0.1 µg/l 432 0 0.00 0
Pesticides - Total 0.5 µg/l 432 0 0.00 0
Polycyclic aromatic hydrocarbons 0.1 µg/l 506 0 0.00 0
Selenium 10 µg Se/l 506 0 0.00 0
Tetrachloroethene / Trichloroethene 10 µg/l 433 1 0.23 1
Total Trihalomethanes 100 µg/l 952 239 25.11 8
TOTAL   35,636 269 0.75  


National Standards

Parameters Prescribed Concentration
or Value		 Total Number
of Tests		 Number of Tests
Failed		 % of Tests
Failed		 Number of
Zones with
Failures
Aluminium 200µg Al/l 2,298 96 4.18 7
Colour 20 mg/l Pt/Co scale 1,969 18 0.91 14
Hydrogen Ion 6.5 - 10 pH value 1,970 8 0.41 5
Iron 200 µg Fe/l 1,971 41 2.08 26
Manganese 50 µg Mn/l 1,971 11 0.56 10
Odour 3 @ 250C dilution number 1,969 0 0.00 0
Sodium 200 mg Na/l 507 0 0.00 0
Taste 3 @ 250C dilution number 1,969 0 0.00 0
Tetrachloromethane         3 µg/l 433 0 0.00 0
Turbidity 4 NTU 1,971 1 0.05 1
TOTAL   17,028 175 1.03  


Additional European Monitoring Requirements

Parameters Prescribed Concentration
or Value		 Total Number
of Tests		 Number of Tests
Failed		 % of Tests
Failed		 Number of
Zones with
Failures
Ammonium 0.5 mg NH4/l 1,970 2 0.10 2
Chloride 250 mg Cl/l 433 0 0.00 0
Clostridium perfringens 0/100 ml 3,192 19 0.60 4
Coliform bacteria 0/100 ml 5,094 24 0.47 20
Colony counts @ 220C No abnormal change 1,971 0 0.00 0
Colony counts @ 370C No abnormal change 1,971 0 0.00 0
Conductivity 2500 µS/cm 3,225 0 0.00 0
*Gross Alpha 0.1 Bq/l 432 0 0.00 0
*Gross Beta 1 Bq/l 432 0 0.00 0
Hydrogen Ion >9.5 pH Value 1,970 4 0.20 3
Residual disinfection
(Free chlorine) mg/l		   5,086 0 0.00 0
Residual disinfection
(Total chlorine) mg/l		   5,087 0 0.00 0
Sulphate 250 mg SO4/l 430 0 0.00 0
Total organic carbon No abnormal change 435 0 0.00 0
Tritium (for radioactivity) 100 Bq/l 432 0 0.00 0
TOTAL   32,160 49 0.15 0

*Monitored for the calculation of total indicative dose.