Using a Private Water Supply

Relevant Person

The relevant person is defined in Section 80 (7) of the Water Industry Act 1991 as;

  • The owner or occupier of the premises supplied; and
  • The owner or occupier of the premises where the source of the supply is situated even if the source lies outside the local authority's area; and
  • Any other person who exercises powers of management or control in relation to that source

These definitions are intended to provide sufficient flexibility to take account of the wide variety of arrangements by which people access private water supplies and therefore it is likely that there may be more than one relevant person for a single supply.

The implications to the relevant person(s) are dependent on the type of private supply (PDF 77KB) used.

Ensuring the supply complies with the Regulations

The local authority has a duty under the Regulations to conduct a risk assessment of all private water supplies within its area (except for single domestic dwellings). The main purpose of the risk assessment is to identify any risks to the supply and ensure appropriate measures are put in place to mitigate against these risks.

If the risk assessment identifies any actions or improvement work in order to remove any risks to the supply then the local authority will liaise with the relevant person(s) to ensure the improvements outlined within the risk assessment are completed. The Inspectorate has produced guidance that outlines some key measures that can be undertaken to protect the supply (PDF 86KB) against the main forms of contamination.

In the unlikely event that informal negotiations between the relevant person(s) and the local authority fails to secure the necessary improvement work required then the Regulation’s allow local authorities to take formal action in order to ensure the supply meets the requirements of the Regulations.

The risk assessment must be conducted by a competent person, which is the local authority or someone approved as competent by the local authority.

Local Authorities can charge the relevant person(s) in order to cover their costs for conducting their duties. Maximum charges for each service are outlined in the Regulations however the charge should only cover the reasonable cost of conducting each service. The list of charges can be found on the local authority’s webpage or by contacting them directly to obtain a quote.

However to save time and potentially costs, the relevant person(s) can collate relevant information (PDF 433KB) regarding the supply and provide this information to the local authority in advance of their visit. Dependent on the type of supply a local authority may ask for this pre-assessment to be completed as a matter of course.

Sampling and Analysis (Monitoring)

Analysing the water can be useful to verify actual or potential contaminants, or to determine whether any treatment systems are operating satisfactory. It also verifies whether the control measures in place are effective, to ensure the safety of drinking water.

The annual frequency of sampling a supply will be dependent on the volume of water the supply provides and the supply type (e.g. Regulation 8,9 and 10) whilst the parameters required will be determined by the outcome of the risk assessment.

Sufficiency of the Supply

The relevant person(s) is responsible for ensuring the sufficiency of the supply at all times and therefore should have plans in place to deal with insufficiency (PDF 272KB), drought (PDF 120KB) and contamination. Having a plan in place to will reduce the time it will take to respond to and manage any issue and it may help reduce your costs. These plans should outline the procedures in place to provide an alternative supply to all customers fed from the supply during the period of insufficiency.

They should include as a minimum:

  • The total number of consumer supplied
  • Typical amounts of alternative water required for each consumer
  • The type of alternative water that will be provided (bottled water, bowsers or tankers)
  • Plans to cope with a long and short duration of insufficiency
  • Communication during the period

As an ongoing lack of sufficient water poses a potential risk to human health the 1991 Act gives local authorities, if required, the power to serve a Section 80 Notice on a relevant person(s) to take appropriate action to deal with the insufficiency.

The Inspectorate has produced an insufficiency plan template (PDF 81KB) and a contamination plan template (PDF 81KB) to assist the creation of such plans. For further advice regarding contact your local authority

Communication with Users

The relevant person(s) has a responsibility to ensure every user on the supply is made aware of any water quality issues with the supply along with any interim measures that should be taken, for example, boiling the water before use, using bottled water only etc. Some local authorities do this on behalf of the relevant person(s); this should be made clear in communications from your local authority.

Selling a property

Prospective purchasers are advised to obtain (from their solicitor or estate agent) a copy of the risk assessment report and any analytical results to confirm whether the supply is safe and wholesome from the local authority or relevant person(s).  A satisfactory sample in isolation is not confirmation that the supply is safe without the risk assessment. Instructions for operation and maintenance of any plant or treatment systems should be made available to a successful purchaser to allow them to maintain the existing control measures.

The Inspectorate has produced guidance for perspective new buyers in the form of a House Buyers Check List (PDF 95KB).

Page reviewed: 31 August 2016
Page modified: 31 August 2016

Drinking Water Inspectorate