Current improvement programmes

South East Water: Undertakings – Bulk Supplies

WATER INDUSTRY ACT 1991(AS AMENDED): SECTION 19(1)(b)

THE SECRETARY OF STATE FOR ENVIRONMENT, FOOD, AND RURAL AFFAIRS:

  1. is satisfied that South East Water “the Company” in supplying water from imported water from the North Surrey Bulk supply (Affinity Water) and from the Burham Bulk Supply (Southern Water) which may be at risk of exceeding the standards for metaldehyde and total pesticides. This means that the Company is likely to contravene its duty in respect of supplying water which meets the Regulations under Section 68(1)(a) of the Water Industry Act 1991 (as amended) and meets the requirement set in regulation 4(2)(c) of the Water Supply (Water Quality) Regulations 2016 (as amended).
  2. notes that South East Water has on 17 June 2020 given a new undertaking (DWI Ref No: SEW-2020-00004) under the provisions of paragraph 2(b) of the previous undertaking given on 04 June 2014 (DWI Ref no: SEW3380) to replace the undertaking and to take the following steps by the dates shown:

Steps to be taken

(a)

Ensure that metaldehyde has been assessed as a hazard as part of the regulation 28 Risk Assessment for the supply systems supplied by all Water Treatment Works (WTWs) listed in the Annex to this Schedule of Works, according to a Drinking Water Safety Plan approach.
Date: Ongoing

(b) Short term measures

Date: Ongoing until the revocation of this undertaking.

  1. Implement an enhanced monitoring strategy to supplement current regulatory monitoring.
  2. The Company will take all reasonable steps to ensure that the prescribed concentration(s) are not exceeded and any steps necessary must be taken to protect public health. If the concentration in any water sample exceeds the maximum concentration the Company has agreed with Public Health England in the water supply zones listed in the Annex to this Schedule of Works, take all reasonable measures in consultation with local health professionals to minimise the impact on customers.
  3. Report regulatory exceedances of the standards for the metaldehyde and total pesticides parameters to DWI as part of the current monthly exception reporting process.
  4. The Company will implement any necessary shortterm operational measures.
  5. Liaise regularly with the supply water companies on progress with the measures being taken to secure compliance with the metaldehyde standard at the named WTWs.
  6. Where ongoing significant risks are identified the company shall continue the DWSP approach and appropriate measures to mitigate the risk shall continue to be implemented.

(c) Medium term measures

Date: For the duration of the undertaking

  1. Continue to monitor water quality in the zones supplied from the named bulk imports, and liaise regularly with Southern Water and Affinity Water on progress with the measures being taken to secure compliance with the Metaldehyde standard at the named WTWs.
  2. Provide support as required to national, regional and local catchment management initiatives aiming to influence Metaldehyde usage in high risk catchment areas and reduce the amounts reaching water sources.
  3. Provide support as required to industry investigations into the effectiveness, feasibility and cost of sustainable treatment options for Metaldehyde.

(d) Long term measures:

Continually appraise the risk of metaldehyde and the total pesticides parameters as hazards in raw waters as part of the regulation 27/ Risk Assessment for the supply system(s) associated with each relevant treatment works according to a Drinking Water Safety Plan approach, and ensure that Regulation 28 documents are regularly reviewed and updates provided as appropriate.
Date: Ongoing

(e) Reporting: Provide DWI with reports on progress with carrying out the steps set out in the undertaking.

Date: Annually for the duration of the Undertaking. Reporting periods are Jan– Dec. Reports to be submitted by 31 Jan each year that the Undertaking is in place, (except for Jan 2025).

Reports to include at least the following details:

  1. Metaldehyde monitoring data for the zones listed in the Annex to this schedule;
  2. Details of contacts made with the supplying water company concerning the actions that company is undertaking to address the risk of metaldehyde in the water supplied;
  3. Any other relevant information.

(f)

Provide a final report to DWI on the outcome of the activities undertaken by Southern Water and Affinity Water, the solutions implemented and the conclusions drawn from other work carried out. Include as evidence of closure for this scheme appropriate documentation to confirm that the actions set out in this Schedule of Work have been completed and the extent to which the required outcomes have been achieved.
Date: When there is sufficient evidence of suitable mitigation of the risk (i.e. 3 years samples below 0.1ug/l and evidence of stable or decreasing raw water trends) or by 31st March 2025


  1. is satisfied that South East Water has given and is complying with an undertaking to take all such steps as appear to the Secretary of State for the time being to be appropriate to secure or facilitate compliance with the requirement of regulation 4(2)(c) of the Water Supply (Water Quality) Regulations 2016 (as amended)..

Authorised by the Secretary of State to sign in that behalf:
Milo Purcell
Deputy Chief Inspector
Drinking Water Inspectorate
DWI Ref No: SEW-2020-00004
Date: 15 June 2020