Dwr Cymru Cyfyngedig – Water Treatment Works Improvements Hazard Review
Notice under regulation 28(4) of the Water Supply (Water Quality) Regulations 2018 (as amended)
Version Number: 1
Water undertaker as appointed under section 6 of the Water Industry Act 1991 (as amended): Dwr Cymru Cyfyngedig, with registered number 02366777 (hereinafter called ‘the Company’).
Assets affected:
- Water Treatment Works listed in Annex 1 (includes standby works which have not been cut and capped)
Details of this Notice:
- The Drinking Water Inspectorate (‘the Inspectorate’) has received a set of regulation 28(1) reports of the Water Supply (Water Quality) Regulations 2018 (‘the Regulations’) from the Company dated 13 October 2023, which states that there is or has been a significant risk of supplying water from multiple sites (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 Hazards associated with:
Description of Risk | Hazard/Hazardous Event/Parameter | Hazard ID |
Potential for elevated levels of Escherichia coli due to its presence in the raw water, treatment effectiveness or network |
E.coli |
Multiple, for example, D126196 |
Potential for elevated levels of Coliforms due to its presence in the raw water, treatment effectiveness or network |
Coliforms |
Multiple, for example, D126195 |
Potential for elevated levels of Turbidity due to its presence in the raw water, treatment effectiveness or network |
Turbidity |
Multiple, for example, D126201 |
Risk of Insufficient Protozoan (crypto) log reduction and inability to meet Reg 26 based target. |
Cryptosporidium |
Multiple, for example, D186646 |
WTWs unable to operate at design capacity. Potential loss of supply risk. |
No supply |
Multiple, for example, D111607 |
Poor performance of GAC contactors. Media adsorption capacity below acceptable levels. Potential risk of pesticides breakthrough |
Pesticides |
Multiple, for example, D180931 |
Potential for elevated levels of Taste due to its presence in the raw water, treatment effectiveness or network |
T&O |
Multiple, for example, D205392 |
Residual coagulant levels above internal target (10ug/l iron or 20ug/l Aluminium) on a rolling annual mean at the final water sampling point. Potential to cause customer acceptability issues in distribution at this level |
Metals (Manganese, Aluminium, Iron) |
Multiple, for example, D111625 |
Poor control of chlorine dosing. Impact on chlorine residuals in distribution. |
Chlorine |
Multiple, for example, D111516 |
Failure of disinfection plant (e.g. storage tanks, dosing lines, control system), loss of or suboptimal disinfection. Potential microbiological risk. |
Failure of disinfection |
Multiple, for example, D111511 |
- The Company are required to satisfy the following:
Requirements
(a) to maintain the following measures for the period specified in each case:
- Up-to-date works operating manuals and procedures, defining normal operating ranges, with appropriate triggers, response and contingency procedures, with controlled update and review programmes.
Date: Ongoing for the duration of this Notice - Ensure all water quality related operational and maintenance tasks are carried out at the current prescribed schedule.
Date: Ongoing for the duration of this Notice - Ensure the works control, shutdown and restart systems are operational. That monitors are calibrated at the predefined frequencies and that up to date calibration/testing records are kept.
Date: Ongoing for the duration of this Notice - Ensure operational staff are kept up to date on policy and procedural changes through training, competence assessment, exercises and operational auditing of any procedural changes.
Date: Ongoing for the duration of this Notice - Effective microbiological and chemical parameter monitoring in line with company procedures for existing water quality risks, and when new risks to water quality from the asset are identified.
Date: Ongoing for the duration of this Notice - Maintain records (including any commissioning records) of remedial work completed on all water treatment works.
Date: Ongoing for the duration of this Notice - Incorporate summaries of Hazard Review outputs and action completion on all water treatment works compliance failure and event reports submitted to the Inspectorate.
Date: Ongoing for the duration of this Notice - Maintain contingency plans to ensure drinking water quality and sufficiency can be maintained in the event of a risk associated with drinking water quality and sufficiency, which should include liaison with local authorities and Public Health England.
Date: Ongoing for the duration of this Notice - Maintain a register of asset risk through Investment Manager, with regular review and assessment.
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:
- Develop a methodology for the completion of site-specific hazard reviews that includes;
- The assessment of risks to drinking water quality and sufficiency in the catchment
- The maintenance and storage of critical spares for treatment processes.
- Identification of single points of failure
- Identification of critical assets ‘too big to fail’.
- Assessment of risks caused by the treatment process itself (for example disinfection by-products) and water fittings.
- The engineering and technological suitability, age and replacement lifecycle of the assets.
- Compliance with current asset standards / specification.
- A review of contingency plans for all sites covered by the notice.
- The overall assessment of compliance with regulation 26, regulation 31 and the requirements of regulation 4, including generating evidence of compliance in all situations.
Date: 31 May 2025
- Develop a process to enable the recording and documentation of operational and asset base hazards at each water treatment works, ensuring compliance with the methodology developed in (b)1. and regulation 27 and 28(1) reporting.
Date: 31 May 2025 - Pilot the methodology developed in (b)1 for hazard reviews and process in (b)2 at six sites (10%) of varying complexity.
Date: 31 August 2025 - Following completion of (b)3 evaluate the effectiveness of (b)1 and (b)2 and revise methodology and documentation for reporting accordingly.
Date: 30 September 2025 - Develop a programme of work, including timescales, for completing site-specific hazard reviews using the framework developed in (b)1 and process developed in (b)2 for each water treatment works. The programmes should be kept under regular review and a risk-based approach should be used to determine the priority order of sites.
Date: 30 September 2025 - Complete the programme of site-specific reviews in (b)5 for each water treatment works.
Date: 30 April 2027 - Refine asset standards for installation, operation and maintenance based on the outcomes of the reviews in (b)6.
Date: 30 June 2027 - Identify and implement short term mitigation as soon as reasonably practicable, based on risk-based priority, where any hazards that have the potential to contribute to regulation 4 breaches are identified through the completion of (b)3 and 6.
Date: Within a maximum of 12 months from the date of the works Hazard Review - Identify and implement a permanent solution as soon as reasonably practicable, based on a risk-based priority, where any hazards that have the potential to contribute to regulation 4 breaches are identified through the completion of (b)3 and 6.
Date: 31 March 2030 - For any permanent solutions identified in (b)8 and not delivered in (b)9 that are to be included in the Price Review 2029 (PR29) submissions, develop a risk-based quality enhancement programme of work detailing timescales for delivery.
Date: 29 February 2028 - Review the suitability of the company’s asset maintenance plans, maintenance task specifications, maintenance task identification process and internal audit of task completion to ensure maintenance of assets is conducted at an appropriate frequency and standard to maintain the continuous delivery of a wholesome water supply, under regulation 4. Include appropriate methods for escalation and action tracking when equipment defects are identified through task completion.
Date: 30 June 2027 - Implement any improvements as identified in measure (b)11.
Date: 30 June 2028
(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 section (a) and (b).
Date: 28 February 2025 - Implement, and keep under continuous review, the audit strategy defined in measure (c)1.
Date: Ongoing for the duration of the notice, following completion of (c)1.
(d) not to supply water for regulation 4(1) purposes, 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: Annually by 31 January - Provide the methodology framework for site-specific hazard reviews, developed in measure (b)1.
Date: 30 June 2025 - Provide the process for the recording and documentation of assessment of water treatment works risks and appropriateness of treatment and control measures in place, as described in measure (b)2.
Date: 30 June 2025 - Provide a summary report on the pilot programme, and any changes to the methodology or reporting process as described in (b)3 and (b)4.
Date: 31 October 2025. - Provide the programme of works, including timescales, for completing the site-specific reviews, as described in measure (b)5.
Date: 30 November 2025 - On a quarterly basis provide the following (refer to (b)6, 8 and 9);
- Provide an updated programme of work, including any updates to proposed and actual dates of the site-specific hazard review.
- Following completion of each site-specific review, submit a summary report using the relevant proforma of the hazard review findings. Ensure regulation 28(1) reports are kept up to date following each works site-specific review.
- Following completion of site-specific review provide the output actions including delivery dates, at subsequent quarterly updates include updates of progress with interim and permanent mitigations.
- For sites where all residual risks have been permanently mitigated, submit a summary completion report providing evidence of implementation and commissioning of permanent mitigation(s) and evaluation against the audit strategy defined in (c)1.
Date: 28 February 2026, then quarterly by 28 February, 31 May, 31 August and 30 November each year.
- Confirm completion of all water treatment works site-specific hazard reviews, as described in (b)6.
Date: 31 May 2027 - Provide a report into the review of asset standards as described in (b)7.
Date: 31 July 2027 - Provide the risk-based quality enhancement programme of work detailing timescales for delivery for any permanent solutions to be included in the PR29 submissions.
Date: 31 March 2028 - Provide a report on the outcomes of the review as described in (b)11.
Date: 31 July 2027 - Confirm completion of improvements identified following the review in (b)11, as described in (b)12.
Date: 31 July 2028 - Submit the audit strategy for auditing the effectiveness of the measures, as specified in measure (c)1.
Date: 31 March 2025 - Submit any revisions of the audit strategy produced under measure (c)2.
Date: Within 1 month of identification of 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 April 2030
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).
Signed
Nicholas Adjei
Deputy Chief Inspector, on behalf of the Welsh Ministers
30 December 2024
Reference: DWR-2024-00005
Annex 1
All water treatment works, (includes standby works which have not been cut and capped).
Asset reference | WTW Name |
T600812 | ABERGYNOLWYN |
T698096 | ALAW (NORTH) |
T619812 | ALAW (SOUTH) |
T706211 | ALWEN |
T120030 | BOLTON HILL WTW |
T121400 | Bontgoch WTW |
T54090 | BRECON PEN-Y-CRUG |
T54092 | BRECON ST DAVIDS |
T706125 | BRETTON |
T54063 | BROOMY HILL |
T612522 | BRYN COWLYD WTW |
T604612 | BRYNCRUG PEN-Y-BONT |
T77092 | BRYNGWYN |
T54075 | BUILTH WELLS |
T67151 | CANTREF |
T607832 | CAPEL CURIG |
T122057 | CAPEL DEWI |
T48287 | CARNO |
T79177 | CEFN DRYSCOED |
T622922 | CEFNI (ANGLESEY) |
T125012 | Cefnllan WTW |
T641622 | CILFOR (E OF PORTHMADOG) |
T320509 | COURT FARM (CARDIFF) |
T79086 | CRAY (TWYNI) |
T603212 | CWELLYN |
T628512 | CWM DULYN |
T48143 | CWMTILLERY LOW LEVEL |
T612432 | DINAS MAWDDWY |
T642112 | Dolbenmaen WTW |
T54761 | DUNFIELD BOREHOLES |
T637742 | EITHINFYNYDD |
T54227 | ELAN VALLEY |
T792234 | FELINDRE |
T54246 | FFYNNON GAER |
T615242 | GARREGLWYD |
T706250 | GLASCOED |
T625032 | GWASTADGOED |
T303550 | HIRWAUN |
T54391 | LEINTWARDINE BOREHOLE (ADFORTON) |
T54389 | LEINTWARDINE BOREHOLE (LOWER TODDING) |
T706162 | LLANNERCH PARK |
T624722 | LLANYMAWDDWY |
T121997 | LLECHRYD |
T706122 | LLIDIARDAU (NR BALA) |
T67149 | LLWYN-ON |
T641822 | LLYN CONWY |
T54452 | LLYSWEN |
T67357 | MAERDY (H/L AT MAERDY) |
T67358 | MAERDY (L/L AT FERNDALE) |
T54494 | MONMOUTH MAYHILL |
T627432 | MYNYDD LLANDEGAI |
T320200 | NANT-Y-BWCH |
T612652 | PEN-Y-CEFN (NR DOLGELLAU) |
T122900 | PENDINE |
T54666 | PILLETH |
T67034 | PONTSTICILL (TAF FECHAN) WTW |
T123153 | PRESELI |
T618212 | RHIWGOCH |
T48498 | SLUVAD |
T121750 | STRATA FLORIDA |
T48562 | TALYBONT |
T706660 | TRECASTELL |
T67089 | TYNYWAUN (BLAENRHONDDA) |
T54684 | VOWCHURCH BOREHOLES |
T54712 | WHITBOURNE |