Single dwelling supplies
Most private water supplies in England and Wales supply only a single dwelling in isolation, where the water is used exclusively for domestic purposes (for example where the water is used for cooking, drinking, food preparation, bathing, showering and/or 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 mandatory monitoring to be undertaken at these supplies unless the local authority is requested to do so by the owner or occupier of the dwelling. However, the regulations do allow local authorities to monitor single dwelling supplies at their discretion. Where monitoring is requested the following parameters are normally tested as a minimum:
- conductivity
- Enterococci
- Escherichia coli (E.coli)
- hydrogen ion (pH value)
- turbidity
Other additional parameter tests may be carried out as determined by any risk identified by the local authority. The regulations make provision for local authorities to recover sampling visit costs and those for the analysis of parameters specified in the regulations. In Wales these fees cannot exceed the maximum specified in the regulations.
A local authority may monitor a private supply to a single dwelling as part of an investigation, where for example an owner or occupier raises a concern with the local authority about the quality/wholesomeness of their supply.
Depending on the circumstances, a local authority is duty bound to serve a regulation 18 (20 in Wales) notice on the relevant person to protect public health if testing (and or a risk assessment) 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) or being insufficient for domestic purposes, the local authority can, if it so chooses, serve another type of notice under section 80 of the Water Industry Act 1991 to require improvements to the supply to make it wholesome, where it is not a potential danger to human health.
The extent to which a potential risk can be established by testing alone will be limited by the parameters that are selected for analysis. For this reason, a risk assessment is recommended as it will help the local authority to select appropriate test parameters on a risk basis, as well as determine any potential supply deficiencies and routes of contamination. Please note that both the testing and risk assessment of supplies are chargeable/cost recoverable by the local authority.
It is also worth emphasising that the quality of a supply may vary with seasonal changes to the source water, and or the effectiveness of any treatment under these variable conditions. This means that a test result at any given time is not necessarily representative of the water quality at all other times. For that reason, any treatment must be suitable for the worse-case scenario as identified by a risk assessment.
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 any risk assessment undertaken on request identifies a potential danger to human health, then the local authority will usually 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 by the local authority 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 (such as a 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 by the local authority 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 (such as a dwelling being used as a tea shop), see regulation 9 (Wales).
For further information then please contact your local authority.