Notice of Regulation: South West Water Ltd Alderley Treatment Works

Notice under regulation 28(4) of the Water Supply (Water Quality) Regulations 2016 (as amended)

Reference: BRL-2020-00001

Version Number: 4

Water undertaker as appointed under section 6 of the Water Industry Act 1991 (as amended): South West Water Limited, with registered number 02366665 (hereinafter called ‘the Company’).

Assets Affected:

  • Alderley Water Treatment Works (T01)
  • Alderley Supply System (Y01)

Details of this Notice:

  1. The Drinking Water Inspectorate (‘the Inspectorate’) has received a regulation 28(1) report of the Water Supply (Water Quality) Regulations 2016 (as amended) (‘the Regulations’) from the Company dated 08 December 2022, which states that there is or has been a significant risk of supplying water from Alderley Water Treatment Works (and associated assets as applicable) that could constitute a potential danger to human health.
  2. Consequently, this Notice is served on the Company by the Inspectorate on behalf of the Secretary of State, under regulation 28(4) for the assets listed above, for risks associated with:

Description of Risk

Hazard/ Hazardous Event/ Parameter

Hazard I D

Deterioration of communication pipes and service pipes to consumer



Table 1: Table of the hazards, hazardous events, and/or parameters covered by this Notice, including the Hazard I D numbers and the description of risks.
  1. The Company are required to satisfy the following requirements.

The date given is that until or by which the requirements must be maintained or satisfied, as appropriate.


(a) To maintain the following measures for the period specified in each case:

  1. Opportunistic replacement of lead communication pipes during planned mains renewal works.
    Date: Ongoing for the duration of this notice
  2. Lead communication pipes to be replaced at properties where lead sample results are found to be greater than or equal to 8 µg/L.
    Date: Ongoing for the duration of this notice
  3. Continuation and continuous development of the Company’s Lead Strategy.
    Date: Ongoing for the duration of this notice

(b) To review, revise or make operational the following measures, by the dates specified in each case:

  1. Installation of phosphate dosing at Alderley Treatment Works.
    Date: 30 April 2022
  2. Optimisation of phosphate dosing at Alderley Treatment Works to facilitate compliance with the lead standard in the Alderley Supply System.
    Date: 30 April 2023

(c) To audit whether the measures have been effective by the following means:

  1. Define an audit strategy to monitor the effectiveness of the measures specified in sections (a) and (b).
    Date: Complete
  2. Implement, and keep under continuous review, the audit strategy defined in measure (c)1.
    Date: Following completion of measure (c)1 onwards

(d) Not to supply water for regulation 4(1) purposes from Alderley Water Treatment Works, or not to so supply unless the specified conditions below are satisfied:

  1. Not Applicable

(e) To provide the following information in the time and manner specified below to enable monitoring of progress towards the mitigation of the risks:

  1. Provide a progress report annually.
    Date: by 31 January each year.
  2. Confirm completion of the installation of phosphate dosing at Alderley treatment works.
    Date: 31 May 2022
  3. Review the risk assessment for Alderley treatment works as required by regulation 27(3) and subsequently submit a revised regulation 28 report accompanied by a signed board level declaration.
    Date: Complete
  4. Submit the audit strategy for auditing the effectiveness of the measures, as specified in measure (c)1.
    Date: Complete
  5. Submit any revisions of the audit strategy produced under measure (c)2.
    Date: Within 1 month of a revision
  6. Submit a report in the event that any completed measures of this Notice need to be altered in any way, for any reason.
    Date: Ongoing for the duration of this Notice
  7. Submit a satisfactory completion report accompanied by a revised regulation 28(1) report with Board level Director sign-off.
    Date: 30 April 2024

Further Details of this Notice:

  1. Any product or substance used as a result of the requirements in this Notice must comply with regulation 31.
  2. Under regulation 28(6) the Inspectorate, on behalf of the Secretary of State, may by notice served on the Company, revoke or vary this Notice.
  3. Failure by the Company to comply with this Notice may result in enforcement proceedings under section 18 of the Water Industry Act 1991 (as amended).


Nicholas Adjei
Deputy Chief Inspector, on behalf of the Secretary of State for Environment, Food and Rural Affairs
01 February 2023
Reference: BRL-2020-00001 (V4)

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