Information Letter

17 February 2006

Information Letter 5/2006

To: Board Level and Day to Day Contacts of Water and Sewerage Companies and Water Companies in England and Wales

Dear Sir/Madam

 Control of Water Treatment Chemicals

Purpose

1.  You will probably be aware of the recent diesel contamination incident affecting an area of water supply in Exeter.  The purpose of this letter is to seek your co-operation with measures the Inspectorate feels are necessary for public reassurance as regards the safety of drinking water supplies generally.

Background

2.  The Inspectorate last wrote to companies on the matter of “vigilance” with regard to water treatment chemical operations on 16 September 2003 (Information Letter 12/2003).  This letter provided companies with a summary of the Inspectorate’s relevant technical audit findings and highlighted some areas of concern.  The letter also set out the general approach that, in the opinion of the Inspectorate, reflected best practice.

Public Reassurance Steps

 3.  The recent incident involved water treatment (chlorination) at a site other than a water treatment works.  The Inspectorate is seeking assurance from companies that they have applied the best practice in IL 12/2003 to “all” water treatment operations wherever these take place between the point of water abstraction through the entirety of the distribution network.

 4.  The recent incident involved the connection to the water supply of a water treatment chemical container. However the content of this container was diesel fuel, instead of, or in addition to, the water treatment chemical.  The Inspectorate is seeking assurance from companies that the scope of their operating practices and procedures robustly addresses the particular risk that “the contents of a container may not be as marked at the time it is connected to the water supply”.

 5.   Please provide confirmation in writing to the Inspectorate by 3 March 2006 that the company’s chief operating officer (or equivalent) is fully informed of, and satisfied with, the company’s water treatment chemical handling processes and procedures,   and that he/she is content these are regularly audited and revised in light of performance management data, including near misses.

Enquiries

Copies of this letter are being sent to Pamela Taylor, Chief Executive, Water UK; Richard Wood, Water Supply and Regulation Division, Department for Environment, Food and Rural Affairs; June Milligan, Environment Division, Welsh Assembly Government; Colin McLaren, Drinking Water Quality Regulator for Scotland; Randal Scott, Drinking Water Inspectorate for Northern Ireland; Chairs of the Consumer Council for Water Committees; Rowena Tye, Office of Water Services; Tony Smith, Chief Executive, Consumer Council for Water; Tony Warn, Environment Agency; Nigel Harrison, Food Standards Agency and Gary Coleman of the Health Protection Agency.

This letter is being sent electronically to Board Level and day to day contacts. Please acknowledge receipt by email to dwi.informationletters@defra.gsi.gov.uk. Hard copies are not being sent but the letter may be freely copied.  Any enquiries about the letter should be addressed directly to Professor Jeni Colbourne, via e-mail to suzanne.calmels@defra.gsi.gov.uk

Yours faithfully

Prof. Jeni Colbourne MBE
Chief Inspector of Drinking Water