Private water supply risk assessments

The Private Water Supply Regulations 2009 require us to undertake a risk assessment survey of certain private water supplies every five years. This does not, however, include domestic properties where only a single house uses the supply.

Reasons for risk assessments

If you have a private water supply we want to help you ensure it is safe to use. The risk assessment aims to identify any potential problems that could affect the quality of the water supply so that these may be dealt with before a problem occurs.

The risk assessment involves a site visit to survey the supply from the source of the water (spring or borehole) through to the consumer's tap. This includes any water holding tanks, the distribution system and any water treatment system on the supply. Following the site visit, we will contact you to discuss any improvement measures required to protect or improve the quality of your water supply.

A fee is charged for the risk assessment, which is based on the time taken for an officer to complete the risk assessment. The total cost is divided between all of the properties on that supply.

Sampling and risk assessment costs

We charge a fee for the collection and analysis of the routine quality samples we are required to take.

There is also a fee for the risk assessment survey which we are required to carry out every five years. Where the water supply serves more than one property we will split the total cost between all of the properties using the supply.


Private water supply charges
Item Cost
Collection of water sample £110
Analysis of water sample Actual cost set by laboratory.
Risk assessment £70 per hour of officers' time.

When a risk assessment is being undertaken, there is no charge for the collection of the water sample. No fee is payable where a sample is taken and analysed to confirm or clarify the results of the analysis of a previous sample.

Private water supply other possible charges
Item Cost
Investigations (each visit) £110
Granting an authorisation £100

Dairy farms with a private water supply

We can also collect and analyse samples from dairy farms on a private water supply to provide evidence of dairy compliance with hygiene standards. If you are a dairy farmer that requires this service, please contact us to request the cost and book a sample collection time.

Private water supply that fails routine sampling

If we take a routine sample from a private water supply and it fails to meet the national drinking water standards, we will contact the affected properties and provide advice.

If the supply is considered to be hazardous to health, for example, as a result of certain bacteria being present within the sample, then:

  • we will notify all users on that supply of the failure and provide advice on any action to be taken, for example, to boil all water before use;
  • we may carry out an investigation to identify the cause of the failure;
  • we will serve a Notice on the person(s) responsible for the supply. This will detail the action that needs to be undertaken to restore the water quality to the required level. Failure to comply with the Notice may result in prosecution. Once the water quality is at the required level, we will notify all the users of the supply.

If the supply fails to meet the national drinking water standards, but the failure is not considered to be a hazard to health, for example, high levels of iron which may stain laundry but may not be considered a risk to health, then:

  • we will notify all users on that supply and provide advice on any actions that would improve the quality;
  • we may carry out an investigation to identify the cause of the failure;
  • we will work informally with the person(s) responsible for that supply to try and improve the quality of the supply.
Last updated: Tuesday, 27 September, 2022.