Notice of Regulation: Barry/Sully




Zone Reference: Z1087N53 – Barry/Sully

Improvement Programme Database Reference number: DWR-2019-00001


  1. Have received a report from Dŵr Cymru Welsh Water (the “company”) dated 25 April 2019 which states that there is or has been a significant risk of supplying water from Barry / Sully that could constitute a potential danger to human health.
  2. GIVE NOTICE to the company under regulation 28(4) of the Water Supply (Water Quality) Regulations 2018 that it must satisfy the following requirements:

For risks associated with:

  • Discolouration and associated customer acceptability due to the condition and operation of the network system.


(a) to maintain the following measures for the period specified

  1. Regulatory sampling of water at Llandegfedd, Court Farm, Llwynon and Cantref water treatment works and at customers’ taps.
    Date: Ongoing
  2. Monitoring, tracking and reporting customer contacts
    Date: Ongoing
  3. Responding as required to any PCV failure or customer contact in line with company procedures. Conduct an investigation to determine the root cause and identify remedial measures to prevent a recurrence
    Date: Ongoing
  4. Liaison with local and public health authorities as appropriate
    Date: Ongoing
  5. Review risk assessments for customer contacts and update regulation 28 report.
    Date: Ongoing

(b) to review, revise and/or make operational the following measures, by the date specified:

  1. Complete Distribution zonal study (DZS) including formulating the methodology for mitigating discolouration risk in this zone.
    Date: Complete
  2. Ensure optimisation of Llandegfedd, Court Farm, Llwynon and Cantref works with 95 percentile less than 20% PCV for iron and manganese.
    Date: Ongoing
  3. Confirm impact of trunk main system on performance of the zone and agree mitigation measures so that it does not impact adversely on customer acceptability
    Date: Ongoing
  4. Confirmation of programme of work identified through the DZS following cost benefit for customer acceptability.
    Date: 30 September 2023
  5. Confirmation of success criteria for demonstration of benefit in delivering the proposed programme of work including commencement dates and timescale for demonstration of benefit.
    Date: 30 September 2023
  6. Delivery of programme of work as identified through DZS in Step (b)4 above.
    Date: 31 March 2025

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

  1. Define a strategy for auditing the effectiveness of the above measures to include the following by Date; 31st May 2019
    Date: Complete
    • Monitoring of iron and manganese levels in samples taken at Llandegfedd, Court farm, Llwynon and Cantref works.
    • Implementation of enhanced sampling programme throughout the zone for Fe and Mn.
    • Review of customer contacts on quarterly basis to measure and monitor change and if necessary escalate remediation as appropriate.
    • DWSP and regulation 28 reports updated in line with any new information arising.
    • Review programme of work and delivery timescales to address priority areas of customer acceptability following updated information.
    • Validate benefits delivered against benefits criteria set.
    • Technical reports for preferred solutions where choices are available.
    • Commissioning, completion and handover certificates for all work undertaken in line with the programme as defined in step (b)4
  2. Implement the audit strategy outlined in (c)1.
    Date: Keep under review, and resubmit when subject to change.

(d) N/A

(e) to provide the following information in the time and manner specified below to enable monitoring of progress towards the mitigation of the risk of supplying water that would constitute a potential danger to human health:

  1. Provide a progress report annually by 31 January and against the following milestones:
    • Provision of the output from DZS as indicated in Step (b)6.
      Date: Complete
    • Provision of the programme of remediation work arising from DZS and criteria for benefit setting as indicated in Step (b)4
      Date: 31 October 2023
    • Delivery of remediation identified in Step (b)6.
      Date: 30 April 2025
    • Initial completion report.
      Date: 31 October 2026
  2. Review the risk assessment for Barry / Sully as required by regulation 27(3) and submit a revised regulation 28 report.
    Date: Ongoing
  3. Submit a satisfactory completion report.
    Date: 31 October 2027

Failure by the company to comply with this Notice may result in enforcement proceedings under section 18 of the Act.

Signed by authority of the Welsh Ministers,
Nicholas Adjei
Deputy Chief Inspector
25 August 2022
DWI Ref: DWR-2019-00001
Version 3

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