Private Water Supplies

Updates to the private drinking water regulations 2017 – the current regulations are being amended and this includes changes to the fees Local Authorities are allowed to charge for services related to private water supplies. The consultation will run for 6 weeks from 12 September to 24 October 2017 and owners of private water supplies are encourage to make their view known via the Defra website.

West Somerset Council has a general duty under the Water Industry Act 1991 to take all steps appropriate for keeping itself informed about the wholesomeness and sufficiency of drinking water supplies in the district, including any private water supply.

A private water supply is any water supply which is not provided by the local water undertaker or company and which is not a "mains" supply.  It includes water intended for human consumption, used for domestic purposes, such as for drinking, washing, in food preparation, heating and also for sanitary purposes.

The Regulations or “The Private Water Supplies Regulations 2016” updated previous provisions and came into force 27th June 2016.  They place a requirement on this local authority to risk assess and carry out water quality inspections to all supplies except those to single domestic dwellings. 

Whilst there is no requirement on the Council to monitor single domestic private water supplies, but they can be monitored by request under Regulation 10.   The standards still apply to these, but local authorities are not required to pro-actively monitor.

Both regulations 9 and 10 specify certain parameters which must be analysed, but with the addition of any others based on risk.  For example, we analyse for arsenic as an additional parameter, as it is found naturally around the Quantocks and occasionally elsewhere.  There is also a relatively new requirement to commence monitoring for radioactive substances, including Radon.

A report for the DWI by Ricardo-AEA (2015) had identified aquifers in the West Somerset area as a potential high risk for Radon (groundwater).  The Devonian aquifers extending from West Somerset to North Devon are identified as affected aquifers.  Radon (Rn222) is a naturally occurring radioactive gas with a short life of 3.8 days and breaks down into other isotopes and a proportion can be dissolved in water. 

Advice from the Drinking Water Inspectorate explains that consideration can be given by local authorities to carrying out a radon-in-air test within one of more representative properties supplied before monitoring of water is carried out. 

Previously, the focus of this work had in many cases centred on water quality results only, however this service is now based around development of water safety plans and identification by this authority of the critical controls to manage these risks.  Risk assessments are carried out every five years (or sooner based on risk) to all supplies other than those to single domestic properties. 

If at any time within this process, the risk constitutes a potential danger to human health, then we must serve notice.  Notices are either served to restrict (e.g. boil) or prohibit the use.  It is an offence not to comply with any notice served under this part.  

Insufficiency is also a critical control assessed during the Council’s inspections.  It is typically assessed by pressure and flow and supplied through pipework and fittings correctly specified, but also critically regularly maintained to prevent leaks from occurring. 

It is essential to have accurate plans or drawings of these supplies to document the controls.   This authority will always explain the reasons for taking action when the supply constitutes a potential danger to human health. 

For example, where any disinfection plant is installed we would expect to see maintenance records and verification that the disinfection remains effective.  For example;

  • daily free residual chlorine measurements (when chlorine is dosed)
  • UV lamps designed based on maximum anticipated flows with adequate pre-filtration.  Note: Some UV systems have on/off alarms to notify of failure, whereas others in more critical uses can also have alarms based on lamp intensity or with automatic shut-down.  Pre-filters must also be replaced based on systematic controls e.g. either by visual observation or pressure readings

In relation to these inspections, the Council will give at least twenty-four hours’ notice of the intention to carry out an inspection; however there may be occasions when access is required at any reasonable time.

The monitoring is subject to the following charges shown in the document Private Water Supplies Fees & Charges to account for the reasonable costs incurred and are based on the officer time (e.g. time on site, time for preparation, the report and mileage) and analytical costs borne by the Council in discharging these duties. 

These charges are levied on the relevant person responsible for supplying the water, which is typically the land-owner where the source is situated.  Relevant persons are defined by the Act under section 80.

In order to assist in the provision of information and to ensure the details held are correct, there is a registration form available (see Related Documents).  

For new private water supplies being installed or even ones being brought back into use, they must not be used until such time this authority has inspected the works.  The reason for this is, to prevent potential danger to human health.   Registration applies to supplies being brought back into use or new supplies being installed, but which fall under the scope of this Council’s inspection program e.g. other than a single domestic dwelling which are not provided as part of a commercial or public activity.

Should it appear that your water supply has not been tested or you require additional information please contact the Council on 01643 703704 or email