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Notice of Regulation: Thames Water – Risk Assessment and Resilience

Completion Date: 31/12/2022
Ref: TMS-2020-00003

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

Thames Water Utilities Limited: Risk Assessment and Resilience

Reference: TMS-2020-00003

Water undertaker as appointed under section 6 of the Water Industry Act 1991 (as amended): Thames Water Utilities Limited, with registered number 02366661 (hereinafter called ‘the Company’).

Assets affected:
All catchments, water treatment works, service reservoirs and zones in the Thames Water Utilities supply region.

  1. The Drinking Water Inspectorate (‘the Inspectorate’) has on 19th October 2017 received multiple regulation 28(1) reports of the Water Supply (Water Quality) Regulations 2016 (as amended) (‘the Regulations’) from the Company, which state that there is or has been a significant risk of supplying water from all catchments, water treatment works, service reservoirs and zones in the Company’s supply region that could constitute a potential danger to human health or 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:

For risks associated with:

  • Inadequate risk assessment procedure for planned and unplanned work, including competency/training and audit
  • Management of hazards associated with dead legs and Water Fittings Regulations contraventions
  • Return to supply procedure following water quality outages
  • Resilience (contingency planning)
  1. The Company are required to satisfy the following:

Requirements

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

  1. Continued audit programme of planned and unplanned works’ risk assessments to ensure compliance with Company procedures and to permit continuous learning.
    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:

Risk Assessments of Planned and Unplanned Works

    • a) Complete a critical review of the risk assessment process, procedures, competency/training requirements (Production and Network Teams) and audit process for planned and unplanned works.
      Date: Complete (30 September 2018)
    • b) Identify any measures required to address the findings of the critical review completed under measure (b)1.a) above.
      Date: Complete (28 February 2019)
    • c) Implement any required measures identified under measure (b)1.b) above.
      Date: Complete
    • a) Review and resubmit the critical review of the Company’s procedures to ensure the risk associated with the following hazards are addressed within the Company’s risk assessments of planned and unplanned works:
      Date: Complete
      • Company identified dead legs within its network; and
      • Premises that have been confirmed to have mains fed Fluid Category 4 or 5 contraventions of the Water Supply (Water Fittings) Regulations 1999, and which are reasonably deemed to represent a potential risk to the company’s water network under conditions of back-siphonage, as defined with the Company’s Water Regulations Policy document.
    • b) Identify any measures required to address the findings of the critical review completed under measure (b)2.a) above.
      Date: Complete
    • c) Implement any required measures identified under measure (b)2.b) above.
      Date: Complete

Planned Work – Return to Supply of Assets

    • a) Conduct a critical review of the Company’s return to supply procedure for assets following water quality outages.
      Date: Complete (30 September 2018)
    • b) Implement appropriate action to address any findings as identified by the review in (b)3.a) above.
      Date: Complete

Resilience

    • a) Complete critical review of contingency plans for assets.
      Date: Complete (31 March 2019)
    • b) Identify any measures required to address the findings of the critical review completed under measure (b)4.a) above.
      Date: Complete (30 June 2019)
    • c) Implement any required measures identified under measure (b)4.b) above.
      Date: Complete
    • a) Complete a critical review of the Company’s current network modelling capability and consider potential requirements for a new Company wide network model to enable assessment of age of water/time of travel.
      Date: Complete (31 March 2019)
    • b) Identify any measures required to address the findings of the critical review completed under measure (b)5.a) above. This must include the verification of existing company information on water supply routes and the update of the Company’s Drinking Water Safety Plans.
      Date: Complete (30 June 2019)
    • c) Implement any required measures identified under measure (b)5.b) above.
      Date: Complete

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

  1. Define a strategy for auditing the effectiveness of the measures listed in section (b) above. This must include the design and implementation of a regular programme of audit and review (incorporating any lesson learnt or improvements made through implementation of the measures in section (b)).
    Date: Complete
  2. At six monthly intervals review the risk assessment process for planned and unplanned work and make any necessary changes to ensure the process continues to be fit for purpose, useable and that the roles and responsibilities of those involved are clearly defined.
    Date: Ongoing for the duration of the Notice
  3. Implement 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 multiple sites, 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:
    Date: Annually by 31 January
    • Report outlining the completion of measure (b)2.c).
      Date: Complete (28 May 2021)
  2. Submit the strategy for auditing the effectiveness of the measures, as specified in (c)1.
    Date: Complete (30 October 2020)
  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 measure 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 June 2022
  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.
  3. 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
Laura Moss
Deputy Chief Inspector, on behalf of the Secretary of State for Environment, Food and Rural Affairs
29 November 2021
Reference: TMS-2020-00003
Version 2