​A private water supply is one that is not provided by a water company such as wells, boreholes or springs. 

Around 1% of the population in England and Wales has a private water supply to their home.

They are found in the more rural areas of South Gloucestershire.


Private water supplies can be contaminated by: 

  • grazing animals
  • manure being spread 
  • heavy rainfall 
  • pesticides, herbicides and fertilisers 
  • cesspits or septic tanks 

Chemicals which occur naturally like iron or manganese may affect the colour and taste of water but are not usually harmful. 

Risk assessments and sampling requirements

Private water supplies must be risk assessed by us to check the source of the supply and surrounding area for signs of potential contamination.  

The risk assessment may involve checking storage tanks, treatment systems and pipework to identify risks from the source to the consumer’s tap. 

A water sample will be taken from a tap that is used as drinking water. The water will be analysed for levels of microbes and chemicals. 

Commercial and large supplies (more than 50 people) 

A risk assessment must be completed every 5 years and sampled at least once a year. 

Small supplies (less than 50 people and more than one property) 

A risk assessment must be completed every 5 years and sampled dependent on the risk assessment. 

Single private dwellings 

Risk assessment and sampling is only undertaken if requested by owner of the supply. 

Investigation and action

Any sample that fails to meet the required concentrations will result in the supply being investigated to try and determine the reason for this failure.

If a wholesome supply cannot be achieved through implementing physical changes to the supply network then additional water treatment apparatus may be required.

In the event of a failure that may cause an immediate risk to human health, a notice will be served that places a restriction or prohibition on the use of the supply.

Private water supply charges 

The Private Water Supplies (England) (Amendment) Regulations 2018 allow us to charge a fee to any owner of a private water supply for carrying out the risk assessment and monitoring. 

Use the information below to find out the costs of our different services.  

Risk assessment

Charge: £75.54 per hour. Minimum fee of £75.54. 

Additional information: A simple risk assessment and report takes around 5 hours. 


Fee: £81.50

Additional information: The fee is for the visit and to take a sample.


Fee: £75.50 plus analysis costs 

Additional information: An investigation is carried out in the event of a test failure. 



Fee: £75.50 

Additional information: Application for permission to breach a standard temporarily whilst work is carried out​ 

Small supplies

Fee: £31.30 plus cost of each additional parameter identified in the risk assessment. 

Additional information: Where a supply provides <10m3 / day or <50 people and is used for domestic purposes​. 

Commercial supplies (group A)

Fee: £122.20 

Additional information: Group A monitoring is carried out to ensure that water complies with the standards. Where possible it should be carried out at the same time as any requirement for Group B monitoring. 

Commercial supplies (group B)

Fee: £122.20 plus cost of each additional parameter identified in the risk assessment. 

Additional information: Additional parameters are sampled less often to ensure the water complies with all safety standards. 


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