Current improvement programmes

Notice of Regulation: Irby Reservoir




TIRBA – Irby (Grimsby) Reservoir 1
TIRBB – Irby (Grimsby) Reservoir 2
Grimsby/Skegness Supply system, SSC-001-GRI

DWI Reference: ANH-2018-00005


  1. has received a report from Anglian Water Services Ltd (the “Company”) dated 02 September 2017 (the “Report”) which states that there is or has been a significant risk of supplying water from Irby borehole sources 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:

  • Nitrate


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

  1. Regular review and update of groundwater risk assessments.
    Date: On-going for the duration of the notice.
  2. Nitrate exceedance prediction graphs to be regularly updated, and nitrate to be assessed as a hazard as part of the Regulation 27 risk assessment for the supply system supplied by Irby (Grimsby), according to a Drinking Water Safety Planning approach.
    Date: On-going for the duration of the notice.
  3. The existing blending option of the higher nitrate sources with the lower nitrate sources within the Grimsby/Skegness supply system shall be managed and optimised to ensure compliance), until the completion of the additional control measures.
    Date: On-going for the duration of the notice.
  4. Operational and regulatory monitoring for nitrate at the raw water, final water at Irby Reservoir and in the downstream Public Water Supply Zones.
    Date: On-going for the duration of the notice.
  5. Exceedances investigated in line with company procedures.
    Date: On-going 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: On-going 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: On-going 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: On-going for the duration of the notice.
  9. Carry out catchment management work. Support any voluntary initiatives to influence nitrate usage in the catchments upstream of Irby Reservoir, 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: On-going for the duration of the notice.

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

  1. Carry out more intensive investigation to provide further information to confirm steps to be taken and project completion dates.
    Date: Completed
  2. Complete planning, design and procurement arrangements to provide ion exchange treatment at Littlecoates borehole site.
    Date: 30 June 2020
  3. Complete construction, installation and commissioning of an ion exchange plant at Littlecoates.
    Date: 31 December 2022

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

  1. Define and keep under continuous review an audit strategy to monitor the effectiveness of the above measures, to include the following;
    Date: 30 September 2020
    • Monitoring for nitrate at all high risk raw water sources feeding Irby (Grimsby) Reservoir final water point on a weekly basis, throughout the implementation of the measures in this notice.
    • Continue to monitor nitrate at an enhanced frequency for a period of 12 months following commissioning of the measures outlined above.
    • Investigation of any unusual results.
  2. Implement the audit strategy defined in (c)1.
    Date: For the duration of the Notice.

(d) 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 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:
    • Nitrate monitoring data for the raw and final water, including trend analysis.
      Date: Complete
    • Confirmation of the completion of planning, design and procurement arrangements.
      Date: 31 July 2020
    • Provide a copy of the audit strategy developed in (c)1.
      Date: 31 October 2020
    • Confirm completion of step (b)3.
      Date: 31 January 2023
  2. Review the risk assessment for Irby (Grimsby) Reservoir as required by regulation 27(3) and subsequently submit a revised regulation 28 report accompanied by a signed board level declaration.
    Date: From time to time and by 21 February 2023
  3. Submit a satisfactory completion report.
    Date: 31 January 2024

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
04 March 2020
DWI Reference: ANH-2018-00005
Version 2