Single dwellings

The majority of private water supplies in England and Wales supply only a single dwelling, where the water is used exclusively for domestic purposes (e.g. where the water is used for cooking, drinking, food preparation, bathing, showering and laundry) and where the water is not used for any commercial activity (such as bed and breakfast or tea shop/café). Some examples of single dwellings include the following (this list is illustrative and is not exhaustive):

  • a house (detached, semi-detached, terraced)
  • a bungalow/chalet (detached, semi-detached)
  • flats/apartments (where the supply feeds a single residence only)

Monitoring Requirements

The regulations in England and Wales do not require monitoring to be undertaken at these supplies unless the local authority is requested to do so by the owner or occupier of the dwelling.  If monitoring is requested the local authority should test for the following parameters as a minimum: 

  • Conductivity
  • Enterococci
  • Escherichia coli (E.coli)
  • hydrogen ion (pH value)
  • turbidity

The regulations make provision for local authorities to recover their costs for any monitoring requested.  In Wales these fees cannot exceed the maximum specified in the regulations.

A local authority may monitor a private supply to a single dwelling, for example if they are concerned that the supply presents a potential danger to human health. However in this instance they cannot charge the owner or occupier the cost of conducting this monitoring.

Depending on the circumstances, a local authority is duty bound to serve a regulation 18 (20 in Wales) notice to protect public health if testing identifies that a supply to a single dwelling is a potential danger to human health.

Also, where appropriate, if after 28 days of the local authority establishing the cause of water being non-compliant with regulatory standards (it is unwholesome) the local authority can, if it so chooses, serve another type of notice under section 80 of the Water Industry Act 1991, where circumstances permit it.

When testing a supply, the extent to which a potential risk to it is established will be limited by the parameters that have been selected for testing. This is particularly true when the supply has not been risk assessed. For this reason, a risk assessment is recommended as it will help the local authority to select appropriate test parameters on a risk basis. Please note however that both the testing and risk assessment of supplies are chargeable/cost recoverable by the local authority.

It is also worth noting that the quality of a supply may be variable at different times. For example, it may vary with seasonal changes to the source water, and or the effectiveness of any treatment under these different conditions. Consequently, test results will only be representative of the quality of the water at the precise moment that the sample was taken. For this reason, a supply risk assessment is also recommended.

Risk Assessment Requirements

The Regulations do not require local authorities to conduct risk assessments for private supplies serving only single dwellings used exclusively for domestic purposes unless they are requested to do so by the owner or occupier (including a tenant).

If the risk assessment identifies a risk to human health then the local authority will need to test the quality of the supply by taking a sample/samples for analysis. This analysis may incur additional costs. The local authority must serve a notice in accordance with regulation 18 (20 in Wales) when a supply is a potential risk to human health.

Supplies to rented single dwellings, and those where the water is used as part of a commercial or public activity:

England

If the water at a dwelling is being used as part of a commercial or public activity including, in some cases, where the dwelling is being rented by tenants (including short term lets, such as holiday cottages or bed and breakfast accommodation), monitoring and risk assessment is required.  Dwellings where the water is being used for other commercial, or public activities, include those where part of the premises is open to the public (e.g. garden party) or where food or drink is being prepared, sold and/or consumed by the public (see guidance on regulation 9 in England) will require risk assessing every five years, and monitoring in all cases.

Wales

If the water at a dwelling is being used as part of a commercial or public activity and/or is being rented by tenants (including short term lets, such as holiday cottages or bed and breakfast accommodation), monitoring and risk assessment must be carried out as applicable:  For tenanted single dwellings see guidance for Regulation 11 (Wales) and for those where the water is being consumed as part of a commercial or public activity (e.g. a dwelling being used as a tea shop), see Regulation 9 (Wales).

For further information then please contact your local authority.

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