Guidance documents

Information note on Regulation 20 (Wales)

Regulation 20 (Notices)

Regulation 20 requires that if any private supply of water intended for human consumption constitutes a potential danger to human health, a local authority must serve a notice on any ‘relevant person’ as defined in regulation 2 (see information note). The key point is to protect public health and so timely action is essential.

A notice may be served on one, several or all the relevant persons, depending on the cause and the appropriate mitigation required. To fulfil this duty the local authority must weigh up; its own risk assessment, all the relevant local circumstances, any advice from Public Health Wales, site specific local agreements, covenants or deeds which specify responsibilities for specific aspects of the supply or its management.

Whilst the regulations do not preclude the serving of a regulation 20 notice prior to investigating the cause under regulation 18, corrective action to remediate unwholesome water must be specified in any notice served. The remedial action necessary to restore and maintain the wholesomeness of the water and safeguard human health would only normally be known following the cause being investigated and identified. Where, following a regulation 18 investigation the cause of unwholesome water is found to be the distribution system with domestic premises, a notice should only be served under these circumstances where the water is made available to the public. A notice must also be served where the cause is not the distribution system within domestic premises. Regulation 20 notices should not be used solely as restriction of use notices.

We have provided some suggestions for restrictions and actions to consider for restoring an acceptable water supply in Annexes 1 and 2 below.

The local authority should:

  • Firstly, ensure that consumers are informed and given advice to enable them to minimise the danger to human health.
  • Serve a notice under regulation 20 on the relevant person(s)1 stating the grounds for serving the notice. This notice may require the prohibition or restriction of the use of the supply. It should specify what other action(s) is/are necessary to protect human health and restore acceptable water supply. The actions necessary to maintain the continued acceptable supply following its restoration should be set out. It may be that the notice contains various actions to be carried out by different relevant persons, but this can be captured on one notice copied to all;
  • Carry out an investigation (see information note for regulation 18) to determine the causes which will inform the improvements necessary, if not already known, and update the risk assessment for the supply.
  • If necessary, amend the notice served under section 20.

If information is not provided by a relevant person, the local authority can use its powers under section 85(1) of the Water Industry Act 1991 to serve a notice on any person requiring that person to provide information about premises on a supply.

Where a risk to health is identified in a supply to a single domestic dwelling, a local authority must serve a notice under regulation 20 on the owner/occupiers requiring action to be taken.

The notice must include the following:

  • Identification of the private water supply (the name and other details of the supply).
  • A unique identification number.
  • The grounds for serving the notice (why the water is a potential danger to human health and, for failures to meet the standard, the parameter involved and its concentration).
  • Prohibition or restriction of use of the supply (advice, for example, to boil water for drinking etc for microbiological failures, not to use water for drinking etc for serious chemical failures such as contamination with hydrocarbons, not to use water standing in the pipework for drinking etc for serious failures of the lead standard).
  • Longer term actions to remediate the supply to protect human health. This should include steps to improve the supply to mitigate the risk and make the supply acceptable.
  • Corrective actions that must be taken in order to;
    • Safeguard human health.
    • Restore acceptable water supply.
    • Maintain continued acceptable water supply following its restoration.
  • A notice can be amended or re-issued considering new information (for example, results of investigations). Any new notice should specify all actions required, including those from the previous notice if relevant. The notice should have a new unique identifying number and reference the previous notice. Please note that advice to boil water is appropriate only as a short-term measure while an investigation is undertaken. It should not be regarded as a permanent solution and the completion deadline for the investigation on the notice should reflect this.

Local authorities may make the notice subject to conditions. It is the local authority’s responsibility to ensure all users of the supply (consumers) are aware of the contents and advice in the notice. They can delegate this to an agreed nominated relevant person. For example, among other steps, they could make it a condition of the notice that it is displayed in a prominent place so that the contents and advice can be seen by all users.

Local authorities could also make it a condition of the notice for the relevant person(s) to provide information about the supply (such as any treatment, the distribution network, the source location etc.) and the users of the supply to assist the local authority.

When it serves the notice, the local authority must advise the relevant person(s) that they can appeal against it (see information note for regulation 21). The local authority must revoke the notice as soon as it is satisfied that the risk to health has been sufficiently mitigated.

The local authority should monitor progress of compliance with the notice. Where the relevant person(s) has not complied with the notice, they have committed an offenceunder regulation 20(6). The local authority should initiate legal proceedings.

Penalties for non-compliance with notices are described in information note on regulation 22.

In addition, where any steps specified in the notice are not undertaken within the time period specified in the notice, the local authority may undertake that work themselves and recover their costs in doing so.

Any regulation 18 notices served under the 2010 Regulations (ie existing notices) are deemed regulation 20 notices under the 2017 Regulations. There is no need to issue them again, although if they are re-issued for other reasons then they should be updated to reflect the 2017 Regulations.

A balance must be struck in weighing the danger to human health in prohibiting the supply or restriction on the use of the supply against the danger to human health of maintaining the supply. Prohibition of supply means that in addition to having no piped supply for drinking, food preparation and cooking (an alternative supply would need to be provided in bottles for these purposes). If there is no water or alternative supply for washing/bathing/showering or toilet flushing this brings significant hygiene risks. It is likely that prohibition of supply will be a last resort. It is more likely that in nearly all cases the local authority will consider restriction of the use of supply.

In addition, where any steps specified in the notice are not undertaken within the time period specified in the notice, the local authority may undertake that work themselves and recover their costs in doing so.

Annex 1 Examples of restrictions are:

  • To boil all water for drinking, cleaning teeth, food preparation, and cooking (when there is a microbiological risk or sample failure);
  • To run off the water standing in the pipework to waste before drawing water for drinking, food preparation, or cooking (when there is a risk of elevated levels of lead, copper, nickel or antimony parameters) until the pipework or fittings within the premises contributing to the failure have been replaced;
  • Not to use water for drinking, teeth cleaning, food preparation, and cooking (when there is a significant failure of a chemical parameter that represents an immediate risk to human health). In this case, consumers will require an alternative supply in tankers, bottles or other containers;
  • Not to use water for bathing and showering when there is a significant failure of a chemical parameter that represents a potential danger to human health, if inhaled or absorbed through the skin or it penetrates the skin through an open cut or wounds. In this case, consumers should be advised to use an alternative supply. The alternative supply provided by the relevant person could be from tankers, bottles or other containers.

Annex 2 Advice that may be offered to consumers:

  • For a microbiological failure, to remove inserts from the tap and thoroughly clean and disinfect the tap or replace the tap or, if the tap is connected to a tank, clean, disinfect and adequately cover the tank, and pending that action advise consumers to boil water for drinking, food preparation and cooking if the local authorities consider the failure a potential danger to human health. Any relevant advice from the local health board should be taken into consideration at this stage;
  • For lead failures, to replace the affected pipework with copper or plastic pipework, and flush water standing in the pipework to waste as an interim measure before drawing water for drinking, food preparation or cooking; or
  • Locate an upstream appliance (for example a water softener) downstream of the kitchen tap.

Where a private water supply serves premises in more than one local authority area, Section 80(4) of the Water Industry Act 1991 requires that either:

  • The local authorities act jointly in serving the improvement notice; or
  • One local authority serves the improvement notice with the consent of the other local authorities.

1 Provided the serving of the notice will not cause a greater potential danger.