Guidance documents

Information note on Regulation 10

For a printable copy of this guidance see: Regulation-10v3-final-2.pdf (dwi.gov.uk).

Regulation 10 (Other Private supplies)

Regulation 10 applies to all supplies other than those where water from a public supply is further distributed (regulation 8), or where water is used as part of a commercial or public activity, or when volume supplied is >10m3/day (regulation 9).

Regulation 10 supplies include:

(a) Those where the supply is <10m3/day, where the water is NOT used as part of a commercial or public activity1. If >10m3/day see regulation 9.

(b) Those where the supply serves a single dwelling. A local authority may monitor the supply as part of this regulation and must do so if requested to do so by the owner or occupier. These supplies do not require regulatory monitoring and risk assessment, unless an owner or occupier requests it 2.

Monitoring and risk assessment

Local authorities are required to monitor regulation 10 supplies at least every five years and more frequently if indicated by the risk assessment. The local authority must monitor for the following parameters:

  • Enterococci; Escherichia coli (E. coli)
  • Conductivity; Hydrogen ion (pH value); Turbidity.

In addition, a local authority must monitor for any other parameter in Parts 1 and 2 of schedule 1 identified as at risk of non-compliance (unwholesome) and/or as a potential danger to health in the risk assessment of the supply.

Local authorities may choose to monitor a supply to a single dwelling if it suspects the water to present a potential danger to human health, but it must not make a charge for this activity in addition to the above parameters.

In the case of new supplies to single dwellings, the local authority is advised to contact the relevant persons and undertake preliminary enquiries to risk assess whether the new supply is likely to present a risk of unwholesome water or a potential danger to human health. For more information, see the information note on regulation 13.


1Where the supply is not metered, this equates to approximately up to 50 persons using a supply for normal domestic purposes. These supplies include those that provide water to a work premises where employees use the water only for domestic purposes (where consumption is <10m3 per day).

2In which case the local authority can charge for this work.

PWS Regulations 2016 (as amended) v.3, February 2021