Private water supplies

A private water supply is any water supply which is not provided by a water company. The source of the supply may be a spring, well, borehole, surface derived or a rainwater harvesting system supply. A supply may serve several properties or commercial or public premises.

All private water supplies in Wales are regulated under the Private Water Supplies (Wales) Regulations 2017.These regulations require the Council to risk assess and monitor:

  1. Commercial supplies (all  supplies where the water is used as part of a commercial or public activity and large domestic supplies – over 50 people): We will monitor these supplies regularly and carry out a risk assessment every 5 years.
  2. Small domestic supplies – (excludes those to a single dwelling only) a supply to less than 50 people but supplying more than one property. We will carry out a risk assessment and sampling every 5 years.
  3. Single property supply (only one property):  we can carry out a risk assessment and sampling on the owner/ occupant’s request.
  4. All other supplies, including those servicing a tenanted single dwelling.

Remember! If you’re supplying other people with water, with or without a fee (e.g. other domestic properties, holiday let, caravan park, camping site etc.), it is your responsibility to ensure that the water meets regulatory standards and that is doesn’t pose a risk to people’s health.



If you need us to take a sample  of your water supply, contact us: 

  • Phone: 01766 771000

The results will be sent to you within 28 days. We will provide an explanation of the results and advise you on how to rectify any problems identified.

Supplies used for commercial or public activity, shared supplies or single tenanted properties are subject to a risk assessment every 5 years. The risk assessment will be from source to tap.



The regulations allow local authorities to charge owners of private supplies for undertaking various activities or duties required by the regulations.

View 2019-20 fees


Private water supply questionnaire

If you use private water supplies – commercially or privately, you should have received a questionnaire through the post. If you haven’t received the questionnaire, you can download it here.

Download private water supply questionnaire

Please return the questionnaire to:

  • E-mail:
  • Post: Pollution Control and Licensing, Public Protection, Council Office, Styd Jêl, Caernarfon, Gwynedd, LL55 1SH


Private distribution system

When a private water company supplies water to a premises where the  person responsible for  it are the water companies customer and another private premises  – for example business parks, caravan parks,  college  campus. In these instances a risk assessment must be carried out to determine any actual or potential hazard and to establish a sampling schedule for the site.


Temporary events

Guidelines for the Provision of Temporary Drinking Water Supplies at Events, is available on Water Health Partnership web site:


Further information

Further information is available from the Regulatory Private Water Supply information leaflet or you can contact us: