Private water supplies

Information about private water supplies and how we regulate supplies within the district

A private water supply (PWS) is any water supply which is not provided by a water company (such as South West Water).

Private water supplies can be obtained from a variety of sources including:

  • boreholes
  • wells
  • springs
  • rivers and streams
  • a private distribution system (An unusual mains water configuration which is privately distributed to a third party)

All private water supplies can pose a potential threat to health unless they are properly protected and treated. You may not be able to tell whether your water is safe as contamination within the water may not smell, taste or appear any different in colour.

In this area private water supplies can often be acidic. This can be a problem by leaching plumbing metals into the water supply. Turquoise staining in sinks and baths or hair discolouration can often be due to acidic water leaching copper from internal pipework.

Private water supplies can contain high concentrations of iron and manganese. This can cause a metallic taste, stain laundry and coat pipes reducing pressure, but importantly can also mean your UV disinfection unit doesn't work properly.

Supplies can be contaminated with microorganisms, some of which are harmful.

All this can be prevented by protecting your water source and by applying appropriate water treatment systems that are regularly serviced

Private Water Supplies (England) Regulations 2016

The Private Water Supplies (England) Regulations 2016 as amended 2018 aim to raise water quality by setting legal quality standards and require councils to sample and risk assess all private water supplies used for human consumption (other than a supply serving only a single owner occupied residential dwelling, where we would do so on request) to ensure supplies meet these standards.

Sampling and risk assessments are also required for all water used in any food-production undertaking for the manufacture, processing, preservation or marketing of products or substances intended for human consumption. The council applies a fee for all sampling and risk assessment work.

What is a large or commercial supply?

This includes supplies serving a B&B, holiday lets, pubs, caravan & camping sites, hotels, cafes & restaurants and to most residential lettings.

Tell us about your supply

This council must keep up-to-date records of all private water supplies in its area.  If you have a new private supply or have commenced a commercial activity, please use our online form to  register your supply or to tell us about any changes in use, ownership or contact details.


Samples from private water supplies will be obtained by an accredited sampler and normally from a kitchen tap and sent for analysis at an approved laboratory.

Large or commercial supplies will normally be sampled once a year, more often if more than 10,000 litres is supplied daily. 

Small supplies serving less than 50 people to more than one owner-occupied residential dwelling will normally be sampled once every 5 years. 

If your supply is only serving an individual owner-occupied residential dwelling we can sample or risk assess at your request – please contact us as below.

Risk Assessments

The Regulations require councils to carry out a risk assessment of each supply (excluding single owner-occupied residential dwellings) every five years.

We will assess the supply from the source through to point-of-use, to identify factors that could lead to contamination of the supply. We will consider how well the source is protected, the distribution system, any pre or post treatment storage, treatment methods in place, whether the system is fitted with an alarm or a system to prevent supply as necessary, the number of people served by the supply and the intended use of the water.

The risk assessment report may include an action list of necessary improvements.


In the event of failure, where a supply is found to be 'unwholesome' or a 'risk to human health' a notice will be served either prohibiting or restricting the supply. The notice will remain in force until remedial action is taken and the Council is called to resample the supply and this analysis confirms the supply is safe.


Any sample that fails to meet the prescribed concentrations laid out in the Private Water Supply Regulations must have an investigation to determine the reason for the failure and to identify what action is needed to improve the supply. This may mean further sampling being conducted at the source, storage tanks and/or other parts of the supply system.


In certain circumstances where a supply fails the water quality standard, but the failure is of a parameter which does not cause a risk to health, the council may grant an 'Authorisation' to exceed the statutory limit. This authorisation would be for a temporary period, while measures are put in place to correct the problem.

Reinstating a supply after a period of disuse or reduced demand

Businesses and second homes sometimes remain empty during 'out of season' periods. If you own a business or home served by a private water supply it is important to consider the following before consuming water from a supply that has not been regularly used:

  • Checks of pipes and fitting for signs of ingress, leaks and biofouling and to check if treatments are working normally
  • A review of current water demand and the capacity of tanks and treatments
  • Thorough flushing of the distribution network to renew water stored in tanks and pipework. Flushing should be extended to all affected points of use (showers, taps and toilets)
  • Purging the water source itself may be required if inactive for a significant period
  • Disinfection of the distribution system where appropriate by a suitably trained plumber or water engineer


Council interaction regarding private water supplies is a chargeable service. You can check our environmental health and licensing fees for the relevant fee.

Some Frequently Asked Questions

Why should I register my private water supply with the local authority?

So we can:

  • Arrange any necessary sampling and risk assessment to ensure your supply is safe and you are meeting requirements of letting agents and insurers
  • Advise the appropriate agencies to ensure there is no risk to your supply's catchments area (for example, advising persons undertaking bio-solid spreading on land that there are private water supplies which may be affected)
  • Notify you of any updates of legislation involving private water supplies and your responsibilities

How can I keep my supply safe?

You should routinely check all features of your supply to ensure they are in a good state of repair. The supply needs to be appropriately protected throughout, from source to point-of-use. As a simple guide:

  • the source headworks chamber should be a minimum 150mm above ground and have a watertight locked cover
  • a stock proof fence should be erected 4 metres radius around the source where appropriate
  • you should ensure that no wastes from agriculture or septic tanks etc are discharged within 50 metres of your water source
  • any storage tanks should securely covered and routinely cleansed
  • treatment systems must be appropriate, serviced in accordance with manufacturers recommendations and either include automatic fail-safes or benefit from daily functionality checks

Any necessary treatments should be discussed with your water engineer. It is usual for supplies to be fitted with an Ultraviolet (UV) disinfection unit with a pre-filter to inactivate any pathogens. In addition a pH vessel, fitted prior to the UV pre-filter and internal metal plumbing, can prevent issues with acidic supplies. Solutions are also available to tackle common impurities such as iron & manganese, nitrates and taste & odour. Alarms and automatic shutoffs can be installed to warn you if the UV has failed, or cause the system to stop.  

Contacting us

If you have an enquiry regarding private water supplies, please contact us via our online form or phone 01271 388870.