Private Water Supplies

Note: As of 1st October 2021 Public Health England (PHE) has become United Kingdom Health Security Agency (UKHSA). Where referenced in guidance and on this website, PHE should now be taken to mean UKHSA. The implementation of a Statutory Instrument will correct references in the legislation in the coming months, after which the Inspectorate can correct the corresponding guidance.  References to Public health agencies in Scotland, Wales and Northern Ireland will not be changed.  For more information on the transformation of public health services please see here.

What are Private Water Supplies? A private water supply is any water supply which supplies one or more properties that is not provided by a water company. About 1% of the population of England and Wales use a private water supply. Most of these supplies are situated in remote, rural parts of the country and can originate from a range of sources including boreholes, natural springs and watercourses.

Who regulates private water supplies? 

Local authorities act as the regulators for private water supplies. The Private Water Supplies Regulations place a duty on local authorities to conduct a risk assessment of each private water supply within their area and to undertake monitoring to determine compliance with drinking water standards (except those to single dwellings unless requested). 

Local authorities have powers under the Regulations to require that a supply is improved by the relevant person(s). Local authorities are required to provide certain information, including monitoring data relating to private water supplies to the Secretary of State and Welsh Ministers (in practice the Inspectorate). This submission of data is due on 31 January of every year, for records relating to supplies in their area during the previous calendar year. Local authorities must also provide a summary of the results of private water supplies risk assessments within 12 months of completing them. 

How does the Inspectorate help local authorities to regulate private water supplies? 

The Inspectorate is not the regulator for private water supplies. However, we have a statutory duty to act as technical advisors to local authorities in relation to the implementation of the Private Water Supplies Regulations on behalf of the Secretary of State. We provide technical and scientific advice on all aspects of drinking water quality, including on private water supplies, to local authorities. We do not work directly with consumers or owners of private water supplies, but do respond to any enquiries made to us about private water supplies.  

The Inspectorate publishes an annual report on private water supplies in England and Wales. This presents information based on the updated private supply records provided to the Inspectorate by local authorities in their annual data submissions, along with other information gathered from inspectors in other ways. It is published each year in July and covers the previous calendar year. It includes chapters on: 

  • Private water supplies water quality testing and sample results.
  • Risk management of private water supplies.
  • Research on private water supplies and collaborative work by the Inspectorate.
  • Private water supplies case studies.

Private water supplies are categorised as follows:



Regulation 9 supplies

Large supplies and those used as part of a commercial or public activity  (including some supplies to tenanted single dwellings)

Large supplies and those used as part of a commercial or public activity (excluding all supplies to tenanted single dwellings)

Regulation 10 supplies

Small supplies, including small shared supplies and those to single dwellings only *

Supplies to untenanted single dwellings only

Regulation 11 supplies

Not applicable

Small shared supplies and those to tenanted single dwellings

Regulation 8 supplies

Where a public supply is onwardly distributed to non-water company consumers on a secondary premises

Where a public supply is onwardly distributed to non- water company consumers on a secondary premises.

* Local authorities may monitor supplies that serve only a single dwelling in accordance with regulation 10, but must do so if requested by the owner or occupier of the dwelling.