The Water Supply (Water Quality) Regulations 2018

Regulations 2, 6, 12, 15 and 19

SCHEDULE 2INDICATOR PARAMETERS

(1)

The water should not be aggressive.

(2)

Where treatment to reduce the level of radionuclides in water intended for human consumption has been taken, monitoring must be carried out to ensure the continued efficacy of the treatment.

(3)

Remedial action may be taken by the Welsh Ministers on radiological protection grounds without further consideration and deemed to be justified where radon concentrates exceed 1,000 Bq/1.

(4)

If tritium concentration exceeds its parametric value, an investigation (which may include analysis) of the presence of artificial radionuclides is required.

(5)

May be monitored from samples of water leaving treatment works or other supply point, as no significant change during distribution.

Item ParametersSpecificationConcentration or Value (maximum unless otherwise stated) or StateUnits of MeasurementPoint of compliance
1Ammonium0.50μgAl/lConsumers’ taps
2Chloride (1)250mgCl/lSupply point (5)
3Clostridium perfringens (including spores)0Number/100 mlSupply point (5)
4Coliform bacteria0Number/100 mlConsumers’ taps
5Colony countsNo abnormal changeNumber/1 ml at 22°CConsumers’ taps, service reservoirs and treatment works
6Conductivity (1)2500μS/cm at 20°CSupply point (5)
7Hydrogen ion9.5pHvalueConsumers’ taps
6.5 (minimum)
8Indicative dose (2)0.10mSvSupply point (5)
(a) gross alpha0.1Bq/lSupply point (5)
(b) gross beta1Bq/lSupply point (5)
9Radon (3)100Bq/lSupply point
10Sulphate 1250mgSO4/lSupply point (5)
11Total organic carbon (TOC)No abnormal changemgC/lSupply point
12Tritium (for radioactivity) (4)100Bq/lSupply point
13Turbidity1NTUTreatment works
Notes: