Serving Notices

Where a local authority suspects that a supply is unwholesome or an indicator parameter has been breached it must investigate to establish the cause.  If the water is a potential danger to human health it must serve a notice in accordance with regulation 18 (20 in Wales).  This notice will temporarily require the supply to be prohibited or its use restricted and for the supply to be improved in the medium to long term (to a stated deadline) to mitigate those risks.

If the cause is not a potential danger to human health, remedial work must be completed within 28 days of establishing the cause, and where it is not, the local authority must serve a notice in accordance with Section 80 of the Water Industry Act 1991 (remedial powers).

  • Template for Regulation 18 Notice (England (Word 40KB)) and Regulation 20 Notice (Wales (Word 43KB))
  • Example Regulation 18 Notice for arsenic (England (Word 40KB)) and Example Regulation 20 Notice (Wales (PDF 127KB))
  • Annotated guide to assist with the completion of a Regulation 18/20 notice. England (Word 41KB) and Wales (PDF 127KB)

Local authorities are requested to send copies of all  Regulation 18 (20 in Wales) and section 80 notices, served on relevant persons to the DWI.  These should be sent via the DWI Enquiries email address (  This forms part of the requirement under regulation 14 (2) (16 (2) (a) in Wales) of The Regulations and is used to inform the Chief Inspector’s annual report.

If the relevant person has not provided the local authority with this information on request, the local authority can use its powers under Section 85(1) of the Water Industry Act to serve a Notice on any person requiring that person to provide the information including the pro forma wording of the advice in the Notice.

A local authority is not allowed to charge for serving a Notice under Section 80 of the 1991 Act or a Notice under Regulation 18. However, if the local authority decides to take remedial action itself to improve a private supply (because for example the relevant person(s) had not taken action), the local authority can recover the costs of taking that action from the relevant person(s)

Any person (the relevant person(s) or any other person affected by the contents of a Notice) can appeal, under Regulation 19 (PDF 218KB),(Reg 21 Wales) to the Magistrates court within 28 days of a Notice being served. However it is an offence under Regulation 20 (PDF 234KB) ( Reg 22 Wales) to breach a Notice served under Regulation 18 (Reg 20 Wales) or to fail to comply with the requirements of the Notice.

Page reviewed: 6 January 2020
Page modified: 6 January 2020

Drinking Water Inspectorate