Introduction
A description of private supplies
A private water supply is any water supply, not provided by a water company, where the water is intended for human consumption or for any food undertaking where the quality of the water may affect the final product. These supplies are regulated by the local authority.
3.27% of the population in Wales use a private water supply, although this is believed to be significantly under-reported due to the lack of mandatory registration and local authorities not meeting their statutory reporting duties. 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, watercourses, and the onward distribution of mains water. The number of sites and population is included in Table 1. While the number of supplies has remained stable in the last few years, it is estimated that there are a further 41,764 supplies (Welsh Government, 2021) which are not registered with local authorities.
| Reporting year | Number of local authorities | Number of sites reported | Reported population |
|---|---|---|---|
| 2022 | 22 | 14,933 | 75,475 |
| 2023 | 22 | 14,786 | 64,220 |
| 2024 | 22 | 14,904 | 67,130 |
| 2025 | 22 | 14,902 | 104,431 |
A description of the types of private water supplies, as defined by Private Water Supplies (Wales) Regulations 2016 (as amended) (the Regulations) is provided here – Types of private supplies (Wales) – Drinking Water Inspectorate. Private water supplies serve a range of premises, both domestic and commercial, such as farms, bed and breakfast accommodation, holiday lets, hotels, sporting clubs, manufacturers, and other businesses. They contribute to the economy as well as the health and welfare of a known notable population of around 104,431. The population reported in 2025 is significantly higher than previous years, and analysis of this information would be required to determine the reason.
The standards and principles of regulation are the same for both public and private water supplies: to protect public health equitably regardless of the source of the water supply. The Regulations are underpinned by the principles of risk assessment and risk management to identify, manage and control risks to protect public health and sufficiency.
The locations of private supplies
Private water supplies are found across most regions of Wales. The highest numbers are usually found in rural areas where connection to the public mains network may be difficult. Figure 1 shows the density of private water supplies across Wales.
Fulfilment of statutory duties
In this 15th year of reporting against this current regulatory framework, local authorities are still not fully delivering their statutory duties, which aim to protect public health.
Understanding the state of private water supplies in Wales relies on the provision of information and data by local authorities. The analysis of this information allows national reporting to direct policy change in pursuit of improving the quality of private water supplies. However, this has been impeded by late or absent returns to the Inspectorate of sample data, summaries of risk assessments, and notices which have been served.