South East Water Limited – Halling Water Supply Zone, Discolouration Risk

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

Reference: SEW3598

Version Number: 3

Water undertaker as appointed under section 6 of the Water Industry Act 1991 (as amended): South East Water Limited, with registered number 02679874 (hereinafter called ‘the Company’).

Assets Affected:

• Z322 – Halling Water Supply Zone
• Y324T07 – Halling Chalk Water Supply System
• Y324T08 – Halling Greensand Water Supply System
• Y324T09 – Halling No. 7 Water Supply System

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 01 January 2015 (and subsequent updates), which states that there is or has been a significant risk of supplying water from Halling Water Supply Zone (and associated assets as applicable) that could constitute a potential danger to human health or could be unwholesome.
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:

• Iron
• Manganese
• Turbidity
• Discolouration

3. 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.

Requirements:

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

1. Undertake risk-based enhanced (in addition to routine regulatory sampling) sampling, for iron, turbidity and manganese, from Halling Water Supply Zone (WSZ) and the associated treatment works and reservoirs.
   Date: Ongoing for the duration of this Notice
2. Ongoing maintenance and optimisation of existing treatment processes at Halling Water Treatment Works, with particular regard to the removal of manganese, iron, turbidity and other parameters relevant to discolouration.
   Date: Ongoing for the duration of this Notice
3. Maintain measures within the Halling WSZ to reduce discolouration risk (such as aggressivity control, asset maintenance, calm valve operations, flow/pressure control, mains remediation and replacement and operator training).
   Date: Ongoing for the duration of this Notice
4. Responding as required to any discolouration associated prescribed concentration or value failures or customer contacts, in line with company procedures. Carry out an investigation to determine the root cause of the failure and identify any remedial measures required to prevent recurrence.
   Date: Ongoing for the duration of this Notice
5. Record and monitor customer contacts at appropriate detail.
   Date: Ongoing for the duration of this Notice
6. Liaison with local and public health authorities as appropriate.
   Date: Ongoing for the duration of this Notice
7. Review and update as necessary the regulation 27 risk assessment and corresponding regulation 28(1) risk assessment reports for Halling WSZ as per the Company’s procedures.
   Date: Ongoing for the duration of this Notice
8. Deliver a programme of proactive and reactive flushing work within Halling WSZ, based on consumer contacts and discolouration risk. Review the programme at least annually against the Company’s mains network performance criteria.
   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. Identify the long-term strategy for mitigating the risk of discolouration in Z322 Halling WSZ
   Date: Complete
2. Remediation of distribution mains through targeted mains investment in the following district metered areas (DMAs): Freemasons, Snodland and Hollow Lane, Snodland
   Date: Complete
3. Investigation of the investment required to reduce discolouration risk in Snodland DMA.
   Date: Complete
4. Complete the investment identified in measure (b)3.
   Date: Complete

Discolouration risk reduction programme of work to achieve the required target of 2 or less consumer contacts for discolouration per 1000 population by 31 March 2025 in Halling WSZ.

5. Investigate the root cause of the discolouration issues seen at individual consumer properties (such as those on Pout Road, Snodland) within the Halling WSZ. Identify any necessary mitigation to address the findings of the investigation.
   Date: 30 July 2024
6. Conduct a review of the low turnover issues affecting West Malling DMA. Identify any necessary mitigation to address the findings of the review.
   Date: 31 March 2024
7. Complete a review of the discolouration risk posed by the unflushed trunk mains above 6 inches within and supplying Halling WSZ. Identify any necessary mitigation to address the findings of the review.
   Date: 31 March 2024
8. Conduct an investigation into the 10-inch cast iron main supplying Medway Gate DMA to understand its impact on the DMA. Identify any necessary mitigation to address the findings of the investigation.
   Date: 30 September 2024
9. Investigate the aggressivity of the water with Halling WSZ to understand the discolouration risk implications. Identify any necessary mitigation to address the findings of the investigation.
   Date: 31 March 2024
10. Review the long term strategy for Halling WSZ, and its ability to achieve the required target of 2 or less consumer contacts for discolouration per 1000 population by 31 March 2025 in Halling WSZ. Update the programme accordingly to ensure the target is met.
    Date: 30 October 2024

(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: 31 October 2023
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 Halling WSZ, 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. Submit a report detailing the long-term strategy for mitigating the risk of discolouration in the Z322 Halling WSZ
   Date: Complete
3. Outline the investment required for Snodland DMA (measure (b)3).
   Date: Complete
4. Confirm completion of measures (b)2 and (b)4.
   Date: Complete
5. Report on the outcomes of all investigations in measures (b) 5 to (b) 9.
   Date: 31 October 2024
6. Outcome of the review completed under measure (b)10 and identification of any resulting updates to the programme.
   Date: 30 November 2024
7. Submit the audit strategy for auditing the effectiveness of the measures, as specified in measure (c)1.
   Date: 30 November 2023
8. Submit any revisions of the audit strategy produced under measure (c)2.
   Date: Within 1 month of a revision
9. 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
10. Submit a satisfactory completion report accompanied by a revised regulation 28(1) report with Board level Director sign-off.
    Date: 30 April 2025

Further Details of this Notice:

4. Any product or substance used as a result of the requirements in this Notice must comply with regulation 31.
5. 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.
6. 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).

Signed

Nicholas Adjei
Deputy Chief Inspector, on behalf of the Secretary of State for Environment, Food and Rural Affairs
20 October 2023
Reference: SEW3598 V3