Notice of Regulation: Hardham Water Supply Works

THE WATER SUPPLY (WATER QUALITY) REGULATIONS 2016 (AS AMENDED)

NOTICE UNDER REGULATION 28(4)

SOUTHERN WATER SERVICES LTD: Hardham WTS, Disinfection, Radiation and Hazrev programme

TS003 – Hardham High WSW

DWI Reference: SRN-2018-00021

THE SECRETARY OF STATE:

  1. has on 20 October 2017 with subsequent updates during 2018 received a set of reports (the “Reports”) from Southern Water Service Ltd (the “Company”) which states that there is or has been a significant risk of supplying water from Hardham Water Treatment Works that could constitute a potential danger to human health.
  2. GIVES NOTICE to the Company under regulation 28(4) of the Water Supply (Water Quality) Regulations 2016 (as amended) that it must satisfy the following requirements:

For risks associated with:

  • Radiological (gross alpha)
  • E. coli, Total Coliforms, Enterococci, Clostridium Perfringens
  • Turbidity
  • Cryptosporidium
  • Pesticides
  • No supply

Requirements

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

  1. Ongoing enhanced monitoring of alpha gross radiation at the raw and treated water at Hardham Water Treatment Works.
    Date: Ongoing for the duration of the notice
  2. Ongoing enhanced monitoring of indicative dose as required.
    Date: Ongoing for the duration of the notice
  3. Maintain or implement suitable operational measures at Hardham Water Treatment Works to ensure adequate chlorine contact time is met at all times and that water that is not compliant with the requirements of regulations 4 and 26 is prevented from entering supply.
    Date: Ongoing for the duration of the notice
  4. Continuous on-line chlorine and turbidity monitoring which is linked to appropriate alarms and integrated failsafe shutdown mechanisms.
    Date: Ongoing for the duration of the notice
  5. Ongoing enhanced monitoring of final water turbidity.
    Date: Ongoing until the satisfactory completion of measure (e)1. i)
  6. Automated treatment works shutdown for high turbidity.
    Date: Ongoing until the satisfactory completion of measure (e)1. i)
  7. Divert dirty wash water from the head of the works to discharge when it is at risk of causing elevated turbidity in the treatment process.
    Date: Ongoing until the satisfactory completion of measure (e)1. i)

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

Radioactivity (gross alpha):

  1. Complete a review of the risk of radioactivity (gross alpha) at Hardham WTW. This must include:
    • a) Speciation Sampling of raw water and assessment of the associated total indicative dose for the potential to breach the prescribed concentration;
      Date: Complete
    • b) If required, undertake seasonal sampling for relevant radioactivity parameters;
      Date: Complete
    • c) An investigation into the source of radiation (artificial or natural);
      Date: Complete
  2. Following the completion of measure (b)1., investigate options to mitigate any identified risks. This may include an investigation into the effectiveness of the water treatment process at removing radioactivity.
    Date: Complete
  3. Implement any required measures, as identified under (b)2. above to mitigate any radioactivity risk (as identified under measure (b)1.).
    Date: Complete

All Raw Water abstraction:

  1. Replace all obsolete raw water quality analysers, at the river intake.
    Date: 31 March 2025

River Rother Abstraction:

  1. Remove the silt from within the intake structure
    Date: 31 March 2023
  2. Replace obsolete parts of the PLC of the MCC for the River Rother low lift pumping station
    Date: 31 March 2023

Ground water abstraction:

  1. Reinstate raw water cryptosporidium monitoring to establish the risk.
    Date: Complete
  2. Review the raw water cryptosporidium monitoring data generated by monitors installed for measure iv to assess if further treatment is required on site.
    Date: 30 November 2021
  3. Refurbish headworks of boreholes 6, 10 and 12 and ensure all boreholes have appropriate sanitary seals.
    Date: 31 March 2025
  4. Address issues with deployable output constraints experienced at all boreholes due to infill.
    Date: 31 March 2025

Clarification:

  1. Install leak detection on coagulation PACL dosing lines and integrate into SCADA and clarifier PLC.
    Date: Complete
  2. Replace and relocate coagulation polymer dosing pumps.
    Date: 16 June 2023
  3. Carry out detailed structural survey to establish required remedial works to clarifiers.
    Date: 31 March 2020
  4. Carry out remedial actions from (b)13.
    Date: 31 March 2023
  5. Replace post clarifier turbidity monitors.
    Date: Complete

Rapid Gravity Filters:

  1. Replace post RGF turbidity monitors.
    Date: Complete
  2. Replace RGF PLC system.
    Date: 31 March 2023
  3. Relocate RGF backwash pump starters to the intermediate pumping station MCC and remove redundant RGF MCC.
    Date: 31 March 2023
  4. Cover the RGF inlet channel.
    Date: 31 March 2023
  5. Replace RGF flow control valves with fit for purpose valves and actuators.
    Date: Complete
  6. RGF cells:
    • a. Complete a condition assessment/survey of all RGF cell media and determine improvement requirements.
      Date: Complete
    • b. Provide scope of works for RGF assessment in (a),
      Date: 31 March 2023
    • c. Complete remedial works as dictated by condition assessment (b)1.
      Date: 31 March 2025
  7. Provide additional dirty backwash water storage tank with mixing, and pumping station.
    Date: 31 March 2025

Ozone:

  1. Replace ozone diffusers and clean ozone contact tank.
    Date: Complete
  2. Replace residual ozone monitors.
    Date: Complete
  3. Refurbish ozone generator 2.
    Date: Complete
  4. Replace ozone and GAC PLCs.
    Date: 31 March 2021

GAC:

  1. Complete condition assessment of GAC MCC to determine operational maintenance requirements.
    Date: Complete
  2. Increase GAC media volume in line with the required empty bed contact time, including all necessary enabling works.
    Date: 31 March 2023
  3. Replace GAC flow control valves and actuators.
    Date: 31 March 2023
  4. Complete monitoring and control modifications to incorporate differential pressure and turbidity backwash triggers to GAC system.
    Date: 31 March 2023
  5. Replace GAC under drains and nozzles.
    Date: 31 March 2023

Disinfection:

  1. Investigate solution to ensure that the contact tank at Hardham Water Treatment Works is not used for blending with other supplies.
    Date: Complete
  2. Following the completion of measure (b)28., produce a detailed design (including timescales for completion) to mitigate the identified risk as appropriate.
    Date: Complete
  3. Implement any required measures as identified under (b)29. to mitigate the identified risk as appropriate.
    Date: 31 July 2021
  4. Update the site specific disinfection policy for Hardham Water Treatment Works following the completion of measure (b)34. above to demonstrate unequivocally how disinfection is met at the works.
    Date: 1 month following the completion of (b)34.
  5. Complete a survey of main dose chlorine analysers and develop solution to ensure representative monitoring.
    Date: Complete
    • a. Review and complete design for a rationalisation of service and motive water systems.
      Date: 31 March 2023
    • b. Upgrade service and motive water system to meet site chemical dosing systems’ capacity requirements and have sufficient backflow protection.
      Date: 31 March 2025
  6. Regulation 31 inspection of service water system and post contact tank connections and complete remedial actions.
    Date: Complete
  7. Flow control valve
    • a. Develop a contingency plan for control valve failure.
      Date: Complete
    • b. Complete inspection of the flow control valve between the clear water tank and the high lift pumps.
      Date: 31 March 2023
    • c. Depending on the findings of measure (b)39., complete suitable remedial measures.
      Date: 31 March 2025

Orthophosphate dosing:

  1. Replace control panel with potential relocation to new kiosk.
    Date: 31 March 2023

Run to waste:

  1. Treated water run to waste to be installed.
    Date: 31 March 2023

Sludge Handling:

  1. Rectify the identified deficiencies with the centrifuge.
    Date: Complete
  2. Design and commission solution for polymer mixing facility.
    Date: 31 March 2023

Water Quality Shutdown Panel:

  1. Replace the HMI in the WQSD panel with a higher capacity unit.
    Date: Complete

Site Control and Data Acquisition System:

  1. Upgrade site SCADA system capacity to cover all asset needs on site.
    Date: 31 March 2025

High Lift Pumps:

  1. Installation of a new substation and a new switchboard for new High Lift Pumps
    Date: 31 March 2021
  2. Decommissioning of current switch gear
    Date: 31 March 2021
  3. Replacement of high voltage pumps and switch gear with low voltage equivalents.
    Date: 31 March 2021
  4. Replacement of the Variable Speed Drives and associated control systems.
    Date: 31 March 2021

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

  1. Submit an audit strategy report to the Inspectorate.
    Date: 31 December 2019 for Radioactivity and 31 May 2019 for Disinfection.
  2. Implement the audit strategy outlined in (c)1. above.
    Date: Until revocation of the Notice
  3. Implement the audit strategy submitted under measure (c)1. regulation 28(4) Notice SRN3949.
    Date: Until satisfactory completion of measure (e)1.i)

(d) not to supply water for regulation 4(1) purposes from TREATMENT WORKS OR SUPPLY SYSTEMS

(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:
    • a) Report to confirm details of the strategy for auditing the effectiveness of the measures specified in section (c).
      Date: 31 January 2020 for Radioactivity and 30 June 2019 for Disinfection
    • b) Outline of the review, completed under measure (b)1.,
      Date: Complete
    • c) Report confirming any required measures to mitigate the risk of gross radioactivity (gross alpha) and the proposed timescales for delivery as required under measure (b)2.
      Date: Complete
    • d) Confirmation of the completion of any measures required under measure (b)3.
      Date: Complete
    • e) Confirmation of the Company’s chosen solution as identified under measure (b)28.
      Date: Complete
    • f) Overview of the detailed design and timescales of the chosen solution completed under (b)29.
      Date: Complete
    • g) Confirmation of the rectification of the centrifuge defect
      Date: Complete
    • h) Confirmation report of the satisfactory completion of a year’s ‘demonstration of benefit’ and all works in relation to the sludge improvement measures as previously specified under Notice SRN3949.
      Date: Complete
    • i) Confirmation of the completion of any measures required under measure (b) for River Water Abstraction.
      Date: 31 May 2025
    • j) Confirmation of the completion of any measures required under measure (b) for Ground Water Abstraction.
      Date: 31 May 2025
    • k) Confirmation of the completion of any measures required under measure (b) for Clarification.
      Date: 31 August 2023
    • l) Confirmation of the completion of any measures required under measure (b) for Rapid Gravity Filters.
      Date: 31 May 2025
    • m) Confirmation of the completion of any measures required under measure (b) for Ozone.
      Date: 31 May 2021
    • n) Confirmation of the completion of any measures required under measure (b) for GAC.
      Date: 31 May 2023
    • o) Confirmation of completed solution to ensure that the contact tank at Hardham Water Treatment Works is not used for blending with other supplies is implemented.
      Date: 31 August 2021
    • p) Confirmation of completion of measures under (b) for Motive Water.
      Date: 31 May 2025
  2. Review the risk assessment for Hardham Water Treatment Works as required by regulation 27(3) and subsequently submit a revised regulation 28 report accompanied by a signed board level declaration.
    Date: As required during the Notice and within 2 months of the completion of all work for Hardham WSW.
  3. Submit a satisfactory completion report.
    Date: 30 April 2026

Failure by the company to comply with this Notice may result in enforcement proceedings under section 18 of the Water Industry Act 1991


Signed by authority of the Secretary of State
Milo Purcell
Deputy Chief Inspector
04 December 2020
DWI Reference: LI/SRN/2018/00021
Version 3

Back to top