{
  "url": "https://openlegislation.uk/water-supply-water-quality-regulations-2000/regulation-13",
  "json_url": "https://openlegislation.uk/water-supply-water-quality-regulations-2000/regulation-13.json",
  "legislation": "uksi/2000/3184",
  "legislation_title": "The Water Supply (Water Quality) Regulations 2000",
  "legislation_url": "https://openlegislation.uk/water-supply-water-quality-regulations-2000",
  "path": "regulation/13",
  "kind": "regulation",
  "number": "13",
  "heading": "Sampling at treatment works",
  "text": "(1) Subject to paragraphs (2), (4) and (6), in each year a water undertaker shall take, or cause to be taken, from the point at which water leaves each treatment works which serves its water supply zones, the standard number of samples for analysis—\n(a) for determining the concentration of residual disinfectant;\n(b) for determining whether, in relation to the colony counts and turbidity parameters, water leaving treatment works meets the specifications for those parameters set out in Schedule 2; and\n(c) for testing for compliance with the prescribed concentrations or values in respect of the coliform bacteria, E. coli, and nitrite parameters for water leaving treatment works.\n(2) Where in each of two successive years the results of the analysis of samples taken, subject to paragraph (3), in accordance with these Regulations have established—\n(a) in respect of the coliform bacteria, E. coli or nitrite parameter, that the maximum concentration has not been exceeded;\n(b) in respect of the turbidity parameter, that the specification has been met;\n(c) in respect of the colony counts parameter, that there has been no significant increase,\nthe number of samples to be taken in respect of that parameter in the next following year from the point at which water leaves that treatment works may, subject to paragraph (4), be the reduced number.\n(3) Paragraph (2) shall apply—\n(a) where the following year is 2004, as if for “these Regulations” there were substituted “the 1989 Regulations”; and\n(b) where the following year is 2005, as if before “these Regulations” there were inserted “the 1989 Regulations and”.\n(4) In respect of the coliform bacteria parameter and the E. coli parameter, the reduced number of samples may be taken in accordance with paragraph (2) only if the water undertaker is of the opinion—\n(a) that there is no foreseeable risk that the supply will exceed the maximum concentration for that parameter; or\n(b) that the treatment works is designed to secure that, in the event of a failure of the disinfection process, water that has not been disinfected cannot enter the supply.\n(5) Samples required to be taken by this regulation shall be taken at regular intervals.\n(6) Where a particular treatment works is in use for part only of a year, the minimum number of samples to be taken from that works in that year shall bear to the standard number or, as the case may be, the reduced number, the same proportion as the number of days in that year in which the treatment works has been in use bears to 365.",
  "extent": null,
  "status": null,
  "version": "current",
  "annotations": [],
  "outstanding_effects": [
    {
      "type": "words substituted",
      "affecting": "uksi/2005/2035",
      "affecting_title": "The Water Act 2003 (Consequential and Supplementary Provisions) Regulations 2005"
    },
    {
      "type": "words substituted",
      "affecting": "uksi/2005/2035",
      "affecting_title": "The Water Act 2003 (Consequential and Supplementary Provisions) Regulations 2005"
    },
    {
      "type": "words inserted",
      "affecting": "uksi/2005/2035",
      "affecting_title": "The Water Act 2003 (Consequential and Supplementary Provisions) Regulations 2005"
    },
    {
      "type": "omitted",
      "affecting": "uksi/2007/2734",
      "affecting_title": "The Water Supply (Water Quality) Regulations 2000 (Amendment) Regulations 2007"
    }
  ],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/uksi/2000/3184/regulation/13",
    "retrieved_at": "2026-10-29T08:09:45.572380+00:00"
  },
  "licence": "Open Government Licence v3.0",
  "licence_url": "https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/",
  "attribution": "Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives."
}