Guidance documents

Information note on Regulation 2 (Wales)

For a printable copy see: Regulation-2-WalesV3-final-1.pdf (

Regulation 2 (Interpretation)

Regulation 2 defines the terms used in the Regulations.

‘The Act’ means the Water Industry Act 1991.

‘Accreditation’ means in accordance with BSEN17024 or BSEN17025.

‘Audit and check monitoring’ were replaced by ‘Group A and Group B’ parameters as part of 2017 amendments of the Regulations.

‘Consumer’ means a person to whom a private water supply is provided for human consumption.

‘Disinfection’ means a process of water treatment to remove, or render harmless to health, every pathogenic micro-organism and pathogenic parasite that would otherwise be present in the water and ‘disinfected’ is to be construed accordingly.

E.coli means Escherichia coli, a bacterium indicating evidence of faecal contamination.

‘Indicative dose’ or ‘ID’ means the committed effective dose for one year of ingestion resulting from all the radionuclides whose presence has been detected in a supply of water intended for human consumption, of natural and artificial origin, excluding tritium, potassium-40, radon and short-lived radon decay products; table D of part 3 of schedule 1.

‘Indicator parameter’ means a parameter listed in table C of schedule 1.

‘Local authority’ means any of the following:

(a) the council of a county or county borough;
(b) district council;
(c) the council of a county in which there are no district councils.

‘Parameter’ means a property, element, organism or substance listed in the first column of the tables in schedule 1 as read, where appropriate, with the notes to that schedule and those tables.

‘Prescribed concentration or value’, in relation to any parameter, means the maximum or minimum concentration or value specified in relation to that parameter in the tables in schedule 1 as measured by reference to the unit of measurement so specified, and as read, where appropriate, with the notes to those tables.

‘Private supply of water’ or ‘private water supply’ means a supply of water other than a supply provided directly by a water undertaker or licensed water supplier, and which is comprised of all physical assets from the point of abstraction to the point of use, including associated pipes, fittings and tanks; and

‘relevant person’1 means any or all of the following:

a) The owner and the occupier (who may be the same or different persons) of premises (land and any buildings on it), which are supplied with water for domestic or food production purposes by means of a private supply;
b) The owner and the occupier (who may be the same or different persons) of land on which any part of the supply is situated;
c) Any other person who exercises powers of management or control in relation to that supply.

1 Where more than one relevant person exists, the Water Industry Act 1991 does not advise how costs relating to private water supplies are shared between relevant persons.

PWS (Wales) Regulations 2017, v3 February 2021