Southern Water Services Limited – Service Reservoir Integrity
Notice under regulation 28(4) of the Water Supply (Water Quality) Regulations 2016 (as amended)
Reference: SRN3923
Version: 3
Water undertaker as appointed under section 6 of the Water Industry Act 1991 (as amended): Southern Water Services Limited, with registered number 02366670 (hereinafter called ‘the Company’).
Assets Affected:
- All company service reservoirs
- All company break pressure tanks
- All company water towers
- All company contact tanks
- Excluding those covered by individual legal instruments.
Details of this Notice:
- 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 20 October 2017, which states that there is or has been a significant risk of supplying water from treated water storage vessels (contact tanks, break pressure tanks, water towers and service reservoirs) (and associated assets as applicable) that could constitute a potential danger to human health or could be unwholesome.
- 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 |
|---|---|---|
|
Risk of ingress of surface water through the structures. |
Bacteria (e.g., E. coli, Total Coliforms) |
For example: 45464 and 45463 |
|
Risk of ingress of surface water through the structures. |
Parasites (e.g. Cryptosporidium) |
For example: 45460 |
|
Insufficient water supply to downstream consumers |
No Supply |
For example: 45521 |
- 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:
- Continue to undertake scheduled Southern Water operator site inspections of treated water storage assets.
Date: Ongoing for the duration of this Notice - Continue to undertake grounds maintenance at the standard frequency.
Date: Ongoing for the duration of this Notice - Continue to externally flood test and internally inspect treated water storage assets according to Southern Waters current reservoir programme.
Date: Ongoing for the duration of this Notice - Continue to monitor treated water storage levels via the Southern Water Regional Control Centre.
Date: Ongoing for the duration of this Notice - Continue to carryout maintenance tasks in accordance with Southern Water standards.
Date: Ongoing for the duration of this Notice - Continue to sample treated water storage assets to check compliance at the frequency defined by the annual Southern Water Sampling Programme.
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:
- Develop a programme of work to ensure all treated water storage assets (water service reservoirs, water towers, break pressure tanks and contact tanks) are internally inspected and flood tested on a risk assessed basis where any asset that fails a microbiological standard is prioritised immediately and the remainder at a maximum frequency of assessment of 10 years inspection frequency.
Date: Complete - Identify and keep under continuous review those assets that cannot be internally inspected, and flood tested by the end of March 2020.
Date: Complete - Undertake a gap analysis of sampling facilities at water treated water storage structures against the regulatory requirements for representativeness and produce and develop a programme of work including a phased risk-based priority list for replacement or renovation.
Date: Complete - Review company procedure for flood testing with industry good practice.
Date: Complete - Produce and implement a new company standard for flood testing.
Date: Complete - Produce a new company asset standard for sampling facilities at treated water storage assets.
Date: Complete - Produce a new company standard for grounds maintenance at treated water storage assets.
Date: Complete - Complete the internal inspection and flood testing of all treated water storage assets identified as being removable from supply in AMP6 as per the programme of work in step (b)1 and undertake all remedial measures necessary to ensure the integrity of the asset.
Date: Complete - Complete phase 1 and 2 of the sampling facility improvements in accordance with the priority list defined in measure (b)3 ensuring that the new and/or renovated sampling facilities are compliant with the new company asset standard described in Step (b)4.
Date: Complete - Plan and undertake enabling works to remove the remaining treated water storage assets from supply for inspection and flood testing.
Date: 31 March 2024 - Commission and operate enabling works as per (b)10. Complete the inspection and flood testing on a risk assessed basis and where necessary, complete remedial works at the treated water storage assets previously un-removable from supply as described in step (b)2 achieving a maximum 10-year inspection frequency for all water service reservoirs, water towers and break pressure tanks. If remedial works are unable to be completed by 31 March 2025 and there remains an identified risk to water quality, the Inspectorate must be informed.
Date: 31 March 2025 - Produce and implement a refined risk-based programme of inspection and flood testing to ensure all treated water storage structures are inspected and flood tested as far as is practicable at a maximum frequency of 5 years where the risk is low, moving to a 3- and 1-year frequency of inspections where the risk is medium and high respectively. Keep this programme under continuous review taking into account network and water resources constraints.
Date: 31 December 2025 - Upon the discovery of active ingress into any treated water storage assets:
Implement immediate short term mitigation measures to ensure public health is protected.
Remove the asset from supply and complete the required remedial works.
Where the company are unable to meet part (b)13 a and b, devise and implement a solution to remove the asset from supply at the earliest opportunity.
Date: For duration of notice
(c) To audit whether the measures have been effective by the following means:
- Define an audit strategy to monitor the effectiveness of the measures specified in sections (a) and (b).
Date: Complete - 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 any treated water storage asset, or not to so supply unless the specified conditions below are satisfied:
- 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:
- Provide a progress report annually.
Date: by 31 January each year. - Provide the new company flood testing standard and a report detailing where any changes to the existing protocol have been made.
Date: Complete - Provide a report detailing the programme of work to ensure all treated water storage assets (water service reservoirs, water towers and break pressure tanks) are internally inspected and flood tested at a 10-year inspection frequency. In addition, identify those assets that cannot be in internally inspected and flood tested by the end of AMP6.
Date: Complete - Provide a report detailing the high-level programme of work for the phased replacement or renovation of sampling facilities at treated water storage assets.
Date: Complete - Provide report confirming completion and commissioning of enabling works to remove the remaining treated water storage assets from supply for inspection and flood testing.
Date: 30 April 2024 - Provide report confirming completion of commissioning and enabling works as per (b)10. Provide report for the inspection and flood testing of the remaining treated water storage assets and completed remedial works at the treated water storage assets previously un-removable from supply as described in step (b)2 achieving a maximum 10-year inspection frequency for all treated water storage assets. Confirmation of any assets awaiting remedial work.
Date: 30 April 2025 - Provide report for production and implementation of a refined risk-based programme of inspection and flood testing as per (b)12.
Date: 31 January 2026 - Where ingress has been found and the company are unable to take the asset out of supply immediately, the company shall submit an action plan to detail how the company intends to mitigate the risks associated with ingress in the medium to long term.
Date: As required for the duration of the notice, within 2 months of discovering ingress - Submit the audit strategy for auditing the effectiveness of the measures, as specified in measure (c)1.
Date: Complete - Submit any revisions of the audit strategy produced under measure (c)2.
Date: Within 1 month of a revision - 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 - Submit a satisfactory completion report accompanied by a revised regulation 28(1) report with Board level Director sign-off.
Date: 31 January 2027
Further Details of this Notice:
- Any product or substance used as a result of the requirements in this Notice must comply with regulation 31.
- 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.
- 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
Nick Adjei
Deputy Chief Inspector, on behalf of the Secretary of State for Environment, Food and Rural Affairs
12 October 2023
Reference: SRN3923 V3