Types of private water supply
There are four main types of private water supply.
| Category | Description | Testing |
|---|---|---|
| Single domestic dwelling | One home, no business use | On request |
| Small supply | Serves fewer than 50 people or less than 10m³ of water per day | Every 5 years |
| Large or business supply | Serves more than 50 people or used for business | Every year |
| Private distribution | Water from a company shared with others (for example caravan parks) | Based on risk |
We test private water supplies to check for:
- bacteria
- chemicals
- metals
Testing frequency depends on the type of supply. Risk assessments are usually done every five years.
Sampling and risk assessment costs
Charges depend on the type of supply and the level of risk.
We charge for:
- collecting and analysing routine water quality samples
- carrying out risk assessments
- any extra investigations or authorisations
Each visit also includes a separate sampling charge.
How charges are set
The cost of monitoring and analysis depends on the outcome of the supply’s risk assessment. We recover the full cost charged by the laboratory we use.
If we carry out a risk assessment, investigation, or issue an authorisation, we will charge additional fees.
| Service | Cost |
|---|---|
| Sampling (each visit) | £110 |
| Risk assessment | £75.60 per hour |
| Other investigations (each investigation) | £110 |
| Granting an authorisation (each authorisation) | £110 |
Private water supply fails routine sampling
If your water fails a test:
- you’ll be told what went wrong
- you may need to boil water or stop using it
- you’ll get advice on how to fix the issue
- you may receive a legal notice to make improvements
Improvement notices
If your supply is unsafe, we will issue a notice explaining:
- why the water is unsafe
- what actions are needed
- how long you have to fix it
We will work with you and offer advice to help you meet the necessary standards.
You have the right to appeal for up to 28 days from the date the notice was served.