Notice of regulation: Northumbrian Water Limited – AMP 7 Discolouration, Multiple Zones

Notice under regulation 28(4) of the Water Supply (Water Quality) Regulations 2016 (as amended)

Reference: NNE-2018-00003

Version Number: 2

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:

Supply System Name	Supply System Ref
North Northumberland Potable Water System 1	YNSZ01
Mid Northumberland Potable Water System 2	YNSZ02
Tyne Valley Potable Water System 3	YNSZ03
Fontburn Potable Water System 4	YNSZ04
Wansbeck Potable Water System 5	YNSZ05
Tyneside Potable Water System 6	YNSZ06
North Tyne Potable Water System 7	YNSZ07
Weardale Potable Water System 8	YNSZ08
North Durham Potable Water System 9	YNSZ09
Durham Potable Water 11	YNSZ11
South Durham Potable Water System 13	YNSZ13
Teesdale Potable Water System 14	YNSZ14
Teesside Potable Water System 15	YNSZ15
East Tees Potable Water System 16	YNSZ16

Zones and their Corresponding water treatment works: 

Zone Name	Zone Reference	Corresponding Water Treatment Works	Water Treatment Works Reference
N201 Fenham and Gosforth	Z0021408	Horsley WTW  Whittle Dene WTW	T0700330  T0700351
N203 High Service South	Z0021410	Horsley WTW  Whittle Dene WTW	T0700330  T0700351
N206 Byker and Wallsend	Z0021412	Horsley WTW  Whittle Dene WTW	T0700330  T0700351
N207 Low Service Gateshead	Z0021413	Horsley WTW  Whittle Dene WTW	T0700330  T0700351
N208 Hillhead	Z0021414	Horsley WTW  Whittle Dene WTW	T0700330  T0700351
N213 Birney Hill	Z0021419	Horsley WTW	T0700330
N217 Shotton	Z0021422	Horsley WTW  Warkworth WTW – Southern Trunk Main Supply	T0700330  T0700349
N229 Gunnerton	Z0021431	Gunnerton WTW	T0700325
N230 Berwick	Z0021432	Murton WTW	T0700336
N231 Fowberry	Z0021433	Fowberry WTW	T0700323
N232 Warkworth	Z0021434	Warkworth WTW – Northern Trunk Main Supply	T0700388
N238 Fontburn	Z0021438	Fontburn WTW	T0004769
N239 Moorhouses	Z0021439	Horsley WTW  Whittle Dene WTW  Fontburn WTW  Tosson WTW	T0700330  T0700351  T0004769  T0004807
N240 Whitley Bay	Z0021440	Horsley WTW  Whittle Dene WTW  Fontburn WTW  Tosson WTW	T0700330  T0700351  T0004769  T0004807
N241 Thropton Rothbury And Longhorsley	Z0021441	Tosson WTW	T0004807
N242 Whittington	Z0021442	Whittle Dene WTW	T0700351
N244 Netherwitton	Z0021443	Fontburn WTW	T0004769
T201 Lartington WTW To Longnewton	Z0021455	Lartington WTW – Barnard Castle Supply  Lartington WTW – Final Supply	T0010145    T0005166
T203 Longnewton To Tees Industrial Estate	Z0021457	Lartington WTW – Final Supply  Broken Scar WTW – Final Supply	T0005166    T0005104
T204 Tees Industrial Estate To Redcar	Z0021458	Lartington WTW – Final Supply  Broken Scar WTW – Final Supply	T0005166    T0005104
T206 Nunthorpe	Z0021459	Lartington WTW – Final Supply  Broken Scar WTW – Final Supply	T0005166    T0005104
T207 Stockton	Z0021460	Lartington WTW – Final Supply  Broken Scar WTW – Final Supply	T0005166    T0005104
T208 Redcar	Z0021461	Lartington WTW – Final Supply  Broken Scar WTW – Final Supply	T0005166    T0005104
T211 Ormesby And Longbank	Z0021463	Lartington WTW – Final Supply  Broken Scar WTW – Final Supply	T0005166    T0005104
W201 Honey Hill	Z0021466	Honey Hill WTW	T0001706
W202 Honey Hill Castleside And Dyke Nook	Z0021467	Honey Hill WTW  Mosswood WTW – Durham Supply	T0001706  T0700335
W203 Oliver Burn	Z0021468	Honey Hill WTW  Mosswood WTW – Durham Supply	T0001706  T0700335
W205 Sacriston	Z0021469	Mosswood WTW – Durham Supply	T0700335
W206 Derwent Trunk Main South And Durham	Z0021470	Mosswood WTW – Durham Supply	T0700335
W207 Ferryhill Fishburn And Spennymoor	Z0021471	Mosswood WTW – Durham Supply	T0700335
W208 Wear Valley	Z0021472	Wear Valley WTW	T0015216
W211 Pelton	Z0021473	Honey Hill WTW  Mosswood WTW – Durham Supply	T0001706  T0700335

Details of this Notice:

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 16 October 2016, which states that there is or has been a significant risk of supplying water from multiple sites that could be unwholesome.
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	Description of Risks
Discolouration	Discolouration
Turbidity	Discolouration
Iron	Discolouration
Manganese	Discolouration
Aluminium	Discolouration

3. The Company are required to satisfy the following requirements.

The date given (the ‘date’) 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:

1. Optimisation of treatment for manganese, iron, aluminium and organics removal at the water treatment works.  
   Date: Ongoing for the duration of this notice
2. Optimisation of pH to manage the corrosive nature of the treated water.  
   Date: Ongoing for the duration of this notice
3. Ongoing pipeline management of mains with flow and control operability.
   Date: Ongoing for the duration of this notice
4. Ongoing uni-directional flushing of DMAs, prioritised based on customer contacts.
   Date: Ongoing for the duration of this notice
5. Appropriate risk based inspection and cleaning of the Company’s service reservoirs as set out in the Company’s discolouration strategy.
   Date: Ongoing for the duration of this notice
6. Adequate risk assessment planning, with appropriate sign-off, before completion of any planned work in order to consider and reduce the risk of customer impact.
   Date: Ongoing for the duration of this notice
7. Training of field operatives to facilitate more effective network operation and management and minimise disruption to customer supplies through the Company’s activities.
   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:

1. Review the potential options to effectively mitigate the risk of discolouration with the zones listed within this Notice.
   Complete
2. Implement the Company’s chosen solution, to effectively mitigate the risk of discolouration within the zones listed within this Notice, as identified under measure (b)1.
   Date: 31 March 2026

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

1. Define a strategy for auditing the effectiveness of the measures being delivered in section (b). This must include:
   1. The appropriate operation of water treatment works at all times;
   2. Ongoing monitoring of customer contacts for discolouration (brown, orange or black);
   3. Monitoring of regulatory sample results for the zones supplied
   4. Monitoring of the number of DWI event based contacts
      Complete

2. Implement, and keep under continuous review, the audit strategy defined in measure (c)1.
   Date: Until revocation of this Notice (following the completion of (c)1 above)

(d) Not to supply water for regulation 4(1) purposes from TREATMENT WORKS OR SUPPLY SYSTEMS, or not to so supply unless the specified conditions below are satisfied:

1. 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:
   1. Outline of the review completed under measure (b)1, indicating the Company’s chosen solution and the timescale for completion of said solution.
      Date: Complete
   2. Interim progress reports on covering optimisation in a) and zonal work under b) 2
      Date: Every July and January Until revocation of this Notice
   3. Confirmation of the completion of measure (b)2.
      Date: 30 April 2026
2. Submit the strategy for auditing the effectiveness of the measures, as specified in (c)1.
   Date: Complete
3. Submit any revisions of the audit strategy produced under measure (c)2.
   Date: Within 1 month of a revision
4. Submit a report in the event that any completed measures of this Notice needs to be altered in any way for any reason.
   Date: Ongoing for the duration of this notice.
5. Submit a satisfactory completion report accompanied by a revised regulation 28(1) report with Board level Director sign-off.
   Date: 30 April 2027

Further Details of this Notice:

4. Any product or substance used as a result of the requirements in this Notice must comply with regulation 31.
5. 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

Nicholas Adjei
Deputy Chief Inspector on behalf of the Secretary of State for Environment, Food and Rural Affairs
25 March 2022
Reference: NNE-2018-00003