Northumbrian Water Limited – Hanningfield WTW PFAS
Notice under regulation 28(4) of the Water Supply (Water Quality) Regulations 2016 (as amended)
Version Number: 1
Water undertaker as appointed under section 6 of the Water Industry Act 1991 (as amended): Northumbrian Water Limited, with registered number 02366703 (hereinafter called ‘the company’).
Assets Affected:
- Hanningfield WTW T002
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 21 November 2025, which states that there is or has been a significant risk of supplying water from Hanningfield WTW – T002 (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 |
|---|---|---|
Inadequate treatment process to prevent PFAS compounds entering supply. |
Sum of PFAS (F366) |
ESK-TRE-T002-F366-CFH |
- 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:
- Adhere to operational control measures whenever raw water from the River Blackwater is used at any stage within the treatment process.
Date: Ongoing for the duration of this Notice - Continue operational catchment and treatment sampling programme at the frequency determined by the risk assessment.
Date: Ongoing for the duration of this Notice - Continue regular engagement with relevant stakeholders, to ensure that catchment risk assessments are current.
Date: Ongoing for the duration of this Notice - Engage with public health teams should concentrations of PFAS increase to concentrations >0.01 µg/l.
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:
- Review and update the Regulation 27 risk assessment for PFAS at Hanningfield WTW.
Date: 31 October 2026 - Develop and implement a protocol for immediate investigation following any increase in PFAS concentration resulting in a change in tier classification for any anomalous or elevated PFAS concentrations.
Date: 31 October 2026 - Introduce and implement an enhanced PFAS monitoring and sampling programme, following any use of the River Blackwater source for blending purposes.
Date: 31 October 2026 - Design and implement a proactive and systematic strategy to mitigate the risk of PFAS at Hanningfield WTW.
Date: 31 December 2026 - Select and define a preferred solution to address the PFAS risk at Hanningfield WTW.
Date: 30 September 2027 - Carry out a detailed catchment investigation to identify, characterise and quantify actual and potential PFAS sources within the catchment area.
Date: 30 September 2027
(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: 30 September 2026 - 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 Hanningfield WTW, 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. - Submit a report evidencing and detailing the updated risk assessment for PFAS at Hanningfield WTW.
Date: 30 November 2026 - Submit a report evidencing the developed and implemented protocol for the immediate investigation following any increase in PFAS concentration resulting in a change in tier classification for any anomalous or elevated PFAS concentrations.
Date: 30 November 2026 - Submit a report to detailing and evidencing the implementation of an enhanced PFAS monitoring and sampling programme, following any use of the River Blackwater source for blending purposes.
Date: 30 November 2026 - Submit a report detailing the design and implementation of a proactive and systematic strategy to mitigate the risk of PFAS at Hanningfield WTW.
Date: 31 January 2027 - Submit a report detailing the selected and defined preferred solution to address the PFAS risk at Hanningfield WTW.
Date: 31 October 2027 - Submit a report to evidence the detailed catchment investigation which has identified, characterised and quantified actual and potential PFAS sources within the catchment area.
Date: 31 October 2027 - Submit the audit strategy for auditing the effectiveness of the measures, as specified in measure (c)1.
Date: 31 October 2026 - 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: 30 November 2028
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).
Nicholas Adjei
Deputy Chief Inspector, on behalf of the Secretary of State for Environment, Food and Rural Affairs
15 July 2026
Reference: NES-2026-00001 v1