Current improvement programmes

Notice of Regulation: Wighton Water Treatment Works

NOTICE UNDER REGULATION 28(4) OF THE WATER SUPPLY (WATER QUALITY) REGULATIONS 2016 (AS AMENDED)

Anglian Water Services Limited: AMP7 Wighton Nitrate

Reference: LI/ANH/2018/00003

Water undertaker as appointed under section 6 of the Water Industry Act 1991 (as amended): Anglian Water Services Limited, with registered number 02366656 (hereinafter called ‘the Company’).

Assets affected:

TWIT0: Wighton WTW
North Norfolk Supply System, SSC-001-NNO

  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 03 September 2020 which states that there is or has been a significant risk of supplying water from Wighton WTW (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:

Hazard/Hazardous

Event/Parameter

Hazard ID

Description of Risks

Nitrate

ANH-TWIT0-A012-TR0911

Failure of or no treatment

(Target Standard breach)


  1. The Company are required to satisfy the following:

Requirements

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

  1. Regular review and update of groundwater risk assessments.
    Date: Ongoing for the Duration of the Notice.
  2. Nitrate exceedance prediction graphs to be regularly updated and nitrate will be assessed as a hazard as part of the Regulation 27 risk assessment for the supply system supplied by Wighton WTW according to a Drinking Water Safety Planning approach.
    Date: Ongoing for the Duration of the Notice.
  3. The existing Ion Exchange and blending in place in the North Norfolk supply system shall be optimised to ensure compliance with the nitrate prescribed concentration value (PCV), until the completion of the additional control measures.
    Date: Ongoing for the Duration of the Notice.
  4. Operational and regulatory monitoring for nitrate at the raw water, final water at Wighton WTW and in the downstream Public Water Supply Zones.
    Date: Ongoing for the Duration of the Notice.
  5. Exceedances investigated in line with company procedures.
    Date: Ongoing for the Duration of the Notice.
  6. Implement an enhanced monitoring strategy for nitrate to include the monitoring of all high risk water sources and associated final waters on a weekly basis to supplement the current regulatory treated water monitoring.
    Date: Ongoing for the Duration of the Notice.
  7. Report all exceedances of the nitrate parameter to the Local Authority and Health Protection team and agree further additional steps to protect public health as appropriate.
    Date: Ongoing for the Duration of the Notice.
  8. Report all regulatory exceedances of the standards for the nitrate parameter to DWI as part of the current monthly exception reporting process.
    Date: Ongoing for the Duration of the Notice.
  9. Continue to review the nitrate exceedance prediction graphs.
    Date: Ongoing for the Duration of the Notice.
  10. Support any voluntary initiatives to influence nitrate usage in the catchments upstream of Wighton WTW, taking a risk based approach. Engage with and provide data to the Environment Agency and other relevant stakeholders as required on a regular basis.
    Date: Ongoing for the Duration of the Notice.
  11. Continually appraise the risk of nitrate as a hazard as part of the Regulation 27 risk assessment for the supply systems supplied by Wighton WTW according to a Drinking Water Safety Planning approach, and ensure that Regulation 28 documents are regularly reviewed and updates provided as necessary.
    Date: Ongoing for the Duration of the Notice.

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

  1. Carry out more intensive investigation to provide further information to confirm steps to be taken and project completion dates.
    Date: 31 December 2020
  2. Complete planning, design and procurement arrangements to extend the Ion Exchange treatment at Wighton WTW.
    Date: 31 December 2021
  3. Complete construction, installation and commissioning of an Ion Exchange plant extension at Wighton.
    Date: 31 December 2022

(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 section (a) and (b) including:
    Date: 30 September 2020
    • Monitoring for nitrate at all high risk raw water sources feeding Wighton WTW final water point on a weekly basis, throughout the implementation of the short, medium and long term measures.
    • Continue to monitor nitrate at an enhanced frequency for a period of 12 months following commissioning of the medium term measures outlined above.
    • Investigation of any unusual results.
    • The audit strategy for the Ion Exchange treatment will be determined through risk assessment after the completion of the works.
  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 Wighton WTW, or not to so supply unless the specified conditions below are satisfied:

i. 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 by 31 January and against the following milestones:
    Date: Annually by 31 January
    • Submit a report regarding the audit/monitoring strategy for the demonstration of benefit phase.
      Date: 31 October 2020
    • Submit a report to provide confirmation of steps to be taken and project completion dates from step (b)1;
      Date: 31 January 2021
    • A statement to confirm completion of the planning, design and procurement arrangements from step (b)2;
      Date: 31 January 2022
    • A statement to confirm completion of construction, installation and commissioning of an Ion Exchange plant at Wighton WTW from step (b)3.
      Date: 31 January 2023
  2. Submit a report in the event that any completed measure of this Notice needs to be altered in any way for any reason.
    Date: Ongoing for the duration of this Notice
  3. Review the risk assessment for Wighton WTW as required by Regulation 27(4)and subsequently submit a revised Regulation 28 report accompanied by board level sign off, from time to time, and by 28 February 2023, (approx. 2 months after completion of the work).
    Date: Ongoing and by 28 February 2023
  4. Submit a satisfactory completion report accompanied by a revised regulation 28(1) report with Board level Director sign-off.
    Date: 31 January 2024

  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.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
Milo Purcell
Deputy Chief Inspector, on behalf of the Secretary of State for Environment, Food and Rural Affairs
09 February 2021
Reference: AN-2018-00003
Version 2