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Latest Information Letters to Water Companies Clipboard image
Press Release image Latest DWI Press Releases
16 March 2010 Job Advert for Inspector Posts. Closing date: 30 April 2010.
2 March 2010 Information Letter 02/2010 (PDF 49KB) - Revision of Guidance on the regulatory responsibilities of new (inset) appointees in relation to public water supplies. (Inset Guidance PDF 286KB)
24 February 2010 North East London taste and odour incident
15 February 2010 Information Letter 01/2010 (PDF 75KB) on "Guidance on the use of Ultraviolet (UV) irradiation for the disinfection of public water supplies" (PDF 182KB)
15 February 2010 Updated DWI structure diagram (409KB) and Operations team structure diagram (191KB) from 15 February 2010
4 February 2010 Advert for EPSRC Engineering Doctorate in Sustainability for Engineering and Energy Systems. Closing date 16th February 2010.
4 January 2010 The DWI's response to the consultation on the Cave Review of competition and innovation in water markets (PDF 206KB)
18 November 2009 Revision of Information Letter 05/2009 on Taste and Odour. (Version 2 - PDF 164KB)
12 November 2009 DWI structure diagram (133KB) and Operations team structure diagram (68KB) from 16 November 2009 (as referred to in the information letter 08/2009 (PDF 88KB))
16 October 2009 Information Letter 10/2009 - Revision of Guidance on the Water Supply (Water Quality) Regulations 2000/2001 specific to PFOS (perfluorooctane sulphonate) and PFOA (perfluorooctanoic acid) concentrations in drinking water
12 October 2009 DWI's response to Ofwat's Draft Determinations for the period 2010-2015
7 October 2009 Press Release River Trent pollution incident (PDF 59KB)
15 September 2009 Drinking Water Safety - Guidance to health and water professionals (PDF 5.09MB) - a joint publication by the Drinking Water Inspectorate and the Health Protection Agency which brings together current information and advice on the management of incidents affecting drinking water quality for use by health professionals and members of the water industry.
7 September 2009 Advertisement - Chief Drinking Water Inspector - Principal Scientific Officer, Department of the Environment - Northern Ireland Environment Agency
19 August 2009 Information Letter 08/2009 - Reappointment of Chief Drinking Water Inspector and further update on the restructuring of the Drinking Water Inspectorate (pdf 88KB)
6 July 2009 Memorandum of Understanding agreed between DWI and CCWater (pdf 420 KB)
30 July 2009 Chief Inspector reappointed
14 July 2009 Press Release - Northern Region tap water quality results (pdf 339KB 
13 July 2009 Press Release - Wales tap water quality results (pdf 323KB)
9 July 2009 Press Release - Central and Eastern Region tap water quality results (pdf 433KB)
7 July 2009 Press Release - Western Region tap water quality results
6 July 2009 Press Release - Thames & Southern Region tap water quality results
2 July 2009 Drinking Water 2008 - DWI Annual Report
18 June 2009 Informaton Letter 07/2009 - Sampling during swine flu pandemic (PDF 106KB)
8 June 2009 New telephone numbers for the DWI from 15th June 2009. The main enquiry line will be 0300 068 6400
9 April 2009 Information Letter 06/2009 - The Water Industry (Suppliers' Information) Direction 2009 (PDF 176 KB)
19 March 2009 Information Letter 05/2009 - Guidance on the reporting and investigation of taste and odour detections (PDF 164 KB)
05 March 2009 Information Letter 04/2009 - Submission of raw water monitoring data to the Drinking Water Inspectorate.(PDF 144 KB)
27 February 2009 Information Letter 03/2009 - Further guidance on changes within the Operations team and the Inspector Liaison role.
19 January 2009 Information Letter 02/2009 - Changes to the process for assessment of drinking water quality event notifications. (PDF 106KB)
16 January 2009 Information Letter 01/ 2009 - New Structure for the Drinking Water Inspectorate Operations Team  
13 January 2009 Job vacancies within DWI. Closing date 27th February 2009
5 November 2008 Press Release 03/08 - Pitsford Water Treatment Works – Incident Assessment Concluded
The Drinking Water Inspectorate has today issued the following press release announcing the conclusion of the investigation into outbreak of Cryptosporidiosis in the community supplied by the Pitsford Water Treatment works in Northamptonshire in June 2008.
For a copy of the incident assessment letter . please contact the Inspectorate on 0207 270 3370 or at dwi.enquiries@defra.gsi.gov.uk
20 October 2008 Information Letter 11/08 - The 2009 Periodic Review of Prices - Further Guidance on Drinking Water Quality Requirements
6 October 2008 Information Letter 10/2008 - Publication of the latest version of the Guidance on the Water Supply (Water Quality) Regulations 2000 (England) and 2001(Wales) incorporating the 2007 amendment regulations.
29 September 2008 Job vacancies within DWI. Closing date 24th October 2008
10 September 2008 Information Letter 09/2008 - Publication of research report on N-Nitrosodimethylamine (NDMA) in drinking water and associated guidance to the industry
1 September 2008 NEWS - August 2008 - Mynydd Llandegai Water Treatment Works, North Wales
Following the detection of an increased number of oocycts of the parasite Cryptosporidium in the treated water from the Mynydd Llandegai Water Treatment Works, a boil water notice has been issued to 45,000 people as a precautionary measure. Advice on protecting health has been issued by the National Public Health Service for Wales see http://www.wales.nhs.uk/sites3/news.cfm?orgid=719&contentid=10429 The Drinking Water Inspectorate will investigate and publish findings in due course.
29 August 2008 Information Letter 08/2008 - Changes to the approval of disinfectants for emergency use.
7 August 2008 Information Letter 07/2008 - Guidance on the requirement to submit a risk assessment under regulations 27 and 28 of the Water Supply (Water Quality) Regulations 2000 (2001 in Wales) (Amendment) Regulations 2007
26 June 2008 Drinking Water for England and Wales 2007  report available online
20 June 2008 Information Letter 06/2008  Audit of Regulation 35(1)
19 May 2008 Press Release - Three Valleys pleads guilty to supply water unfit for human consumption
3 April 2008 Private Water Supplies and Bottled Water briefing day - 8th July 2008 at the RIPH
20 March 2008 Job Advert for Inspectors in DWI - closing date 25th April 2008
20 March 2008 Calls for Expressions of Interest for 4 new research projects.  Closing date: 30th April 2008.
17 March 2008 Press Release - Incident Assessment letter on Mythe Water Treatment Works
25 February 2008 Information Letter 5/2008 Concessionary supplies - further guidance
21 February 2008 Information Letter 4/2008 Regulation 31
18 February 2008 Information Letter 3/2008 Guidance on the notification of events
25 January 2008 Information Letter 2/2008 The 2009 Periodic Review of Prices - Guidance on Drinking Water Quality Requirements
14 January 2008 Information Letter 1/2008 The Water Supply (Water Quality) Regulations 2000 as amended - Publication of an unofficial consolidated version of the Regulations
28 December 2007 Information Letter 10/2007 Updated guidance on the notification of events.
03 December 2007 Information Letter 9/2007 The Water Supply (Water Quality) Regulations 2000 (Amendment) Regulations 2007 - Changes to water company data tables
30 November 2007 Information Letter 8/2007 Guidance on interpretation of Regulation 16(2)(d)(i) of the Water Supply (Water Quality) Regulations 2000 (2001 in Wales)
13 November 2007 Incident Assessment Letter now available for Cryptosporidiosis outbreak in North West Wales in 2005. Please call 0207 270 3370 or e-mail dwi.enquiries@defra.gsi.gov.uk" to receive a copy
11 October 2007 Press Release Dwr Cymru Welsh Water pleads guilty to supplying water unfit for human consumption
28 September 2007 Information Letter 7/2007 Outcome of the consultation exercise on amendment to the Water Supply (Water Quality) Regulations 2000 - Publication of the amendment regulations and the government response to the consultation
10 September 2007 Notification of RSC half day seminar Taste and Odour in Drinking Water - Tuesday 20th November 2007
05 September 2007 Information Letter 6/2007 Outcome of the consultation exercise on amendment to the Water Supply (Water Quality) Regulations 2000 - Requirements for raw water monitoring
25 July 2007 FLOOD ADVICE - For consumers affected by the current floods and seeking advice about drinking water issues and other concerns, the Drinking Water Inspectorate supports the advice given by the Health Protection Agency which is available at www.hpa.org.uk/flooding/default.htm.

A regularly updated list of bowser locations for Severn Trent customers is available on the Severn Trent website.

11 July 2007 Latest drinking water quality results - Thames Region
06 July 2007 Latest drinking water quality results - Midlands Region
04 July 2007 Latest drinking water quality results - Southern Region
26 June 2007 Drinking Water 2006 for England and Wales released today
20 June 2007 South West Water pleads guilty to supplying water unfit for human consumption
1 June 2007 Guidance on the Water Supply (Water Quality) Regulations 2000/2001 specific to PFOS (Perfluorooctane Sulphonate) and PFOA (Perfluorooctanoic Acid) concentrations in drinking water
22 May 2007 New Structure for the Drinking Water Inspectorate(2)
09 May 2007 New Structure for the Drinking Water Inspectorate(1)
15 February 2007 Summary report for the vertical audits for pesticide parameters
29 January 2007 Appointment of Deputy Chief Inspector (Operations)
24 January 2007 List of Approved Products and Processes - December 2006
29 December 2006 Consultation Paper on the amendment of the Water Supply (Water Quality) Regulations 2000 and the Water Supply (Water Quality) Regulations 2001
6 December 2006 Press Release United Utilities pleads guilty to charge of supplying water unfit for human consumption
4 December 2006 Information letter 11/2006 Technical audit of water companies under section 86 of the Water Industry Act 1991: Summary report for the vertical audits for non-microbiological parameters, 2005
28 November 2006 Press Release:  NPHS for Wales publishes report on the cryptosporidiosis outbreak which occurred in North Wales in Autumn 2005
23 November 2006 Press Release Thames Water pleads guilty to charge of supplying water unfit for human consumption.
14 September 2006 Information Letter 10/2006   Cryptosporidiosis in England and Wales
11 September 2006 Information Letter 09/2006   Update on the in-situ resin lining of water mains under Regulation 31 (10) (b) of the Water Supply (Water Quality) Regulations 2000 (2001 Wales)
17 August 2006 Call for papers for the forthcoming conference - Water Contamination Emergencies: Collective Responsibility
28 June 2006 Press Release - Inspectorate delivers joined-up action on drinking water quality
16 June 2006 Press Release - Independent test show tap water not affected by Buncefield fire
22 May 2006 Press Release - Yorkshire Water pleads guilty to charge of supplying water unfit for human consumption
17 March 2006 Information Letter 08/2006 Contact arrangements for the notification of events under the Water Undertakers (Information) Direction 2004 and notification of crytosporidium anomalies
17 March 2006 Information Letter 07/2006 Further update on the restructuring of the Drinking Water Inspectorate, including structure diagram
22February 2006 Information Letter 06/2006 DWI Drinking Water Quality Improvement Programmes - Process for agreeing changes to improvement programmes associated with legal instruments
17 February 2006 Information Letter 05/2006 Control of Water Treatment Chemicals
10 February 2006 Information Letter 04/2006 Regulation 31 of the Water Supply (Water Quality) Regulations 2000 and 2001: Annual List of Approved Products and Processes - December 2005
09 February 2006 Information Letter 03/2006 Issues relating to 2006 monthly data submissions to the Drinking Water Inspectorate, and information required for inclusion in the Chief Inspector's Report.
07 February 2006 List of Approved Products and Processes - December 2005
18 January 2006 Information Letter 02/2006 Concessionary Supplies: Reporting of compliance results and the calculation of Operational Performance Indices
06 January 2006 Cryptosporidium Advice Letter Cryptosporidiosis
06 January 2006 Information Letter 01/2006 Annual Provision of Information on Consumer Contacts
05 January 2006 Cryptosporidium Advice Letter Cryptosporidiosis in North Wales
16 December 2005 Information Letter 17/2005 Cryptosporidiosis in England and Wales
4 November 2005 Summary report of the responses and learning from the DWI Local Authority consultation January 2005
21 October 2005

Review of evidence for relationship between incidence of cardiovascular disease and water hardness

The Inspectorate has released a report which reviews the available evidence on any link between water hardness and the incidence of cardiovascular disease. The review  was conducted by a team lead by Professor Paul Hunter at the University of East Anglia.

The main findings of the review was that it found evidence from a number of studies  to support the longstanding apparent inverse relationship between water hardness and cardiovascular disease. At present there is insufficient evidence to confirm whether the apparent effect is causal or to elucidate its nature. The report does not comment on potential policy implications but provides a useful evidence base.

The Inspectorate sees the report as an important building block for informing the scientific debate on the issue of water hardness. The report will be presented at a forthcoming WHO workshop on the issue.

13 October 2005 Information Letter 16/2005 Cryptosporidium web site and the latest revision of Part 1 of the Standard Operating Protocol (SOP)
10 October 2005 Information Letter 15/2005 Distribution Operation and Maintenance Strategies (DOMS) - update to DWI requirements and expectations
10 October 2005 A Brief Guide to Drinking Water Safety Plans (PDF 256KB)
03 October 2005 Newly formed Consumer Council for Water
20 September 2005 Information Letter 14/2005 List of Water Treatment Works in England and Wales
7 September 2005 Information Letter 13/2005 Further updated on the restructuring of the Drinking Water Inspectorate
22 August 2005 Information Letter 12/2005 Guidance on sample and sample extract stability trials and the preservation and preparation of samples for metals analysis.
26 July 2005 Information Letter 11/2005 Guidance to inset appointees on their regulatory responsibilities
15 July 2005 A case control study investigating drinking water & dairy products in the aetiology of Crohn's Disease - A possible role for Mycobacterium avium paratuberculosis -The CMAW Study  - Final Report (Adobe  7.8MB)

plus DWI's Q&A report conclusions
13 July 2005 Information Letter 10/2005 Update on the restructuring of the Drinking Water Inspectorate
30 June 2005 Information Letter 09/2005 Regulation 31 of the Water Supply (Water Quality) Regulations 2000 and 2001: Approval and use of packing materials in water treatment processes
21 June 2005 Information Letter 08/2005 Technical audit of water companies under Section 86 of the Water Industry Act 1991: Summary report for the vertical audits for non microbiological parameters, 2004.
18 May 2005 Guidance to the Water Supply (Water Quality) Regulations for England (2000) and Wales (2001) (pdf 1.9MB)
16 May 2005 Information Letter 07/2005 Contact Arrangements for the Notification of Events under the Water Undertakers (Information) Direction 2004 and notification of cryptosporidium anomalies.
13 May 2005 Information Letter 06/2005 Update on the restructuring of the Drinking Water Inspectorate
10 May 2005 Job Opportunities within DWI (pdf 149KB)
28 April 2005 Memorandum of understanding between the UK Drinking Water regulators.
11 April 2005 Information letter 05/2005 Code of Practice on technical aspects of Fluoridation in water supplies 2005.
08 April 2005 Information letter 04/2005 New Structure of the Drinking Water Inspectorate.
29 March 2005 Regulation 31 letter -Regulation 31 letter 03/2005 Notice of intention to modify conditions of approval for in-situ coatings
24 January 2005 Information letter 03/2005 Guidance on calibration and analytical quality control of residual chlorine measurements.
21 January 2005 Information letter 02/2005 Issues relating to the submission of sample data to the DWI
18 January 2005 Competition - DWI's response to consultation on Access Code Guidance
11 January 2005 Information Letter 01/2005 Requirements for Monitoring Radioactivity in Water Supplies

15 December 2004

Newly revised draft programme for the Conference on Water Contamination Emergencies: Enhancing our Response

25 November 2004

Information letter 14/2004 Cryptosporidium in water supplies: Anomaly reporting for the Water Supply (Water Quality) Regulations 2000 (England) and Water Supply (Water Quality) Regulations 2001 (Wales).

23 November 2004

Information letter 13/2004 Common Carriage: Guidance on the drinking water quality aspects.

12 November 2004

Information letter 12/2004 Guidance on the implementation of paragraph 7(1) of the Water Undertakers (Information) Direction 2004.

4 November 2004

Information letter 11/2004 Information requirements following notification of an exceedence of a regulatory standard

25 October 2004

Information letter 10/2004 Monitoring drinking water at establishments where water is supplied to the public

21 September 2004

3rd Edition of WHO Guideline Values for Drinking Water Quality

The World Health Organisation has published the third edition of its the Guidelines for Drinking Water Quality. The WHO Guidelines form the basis for regulation of drinking water quality all over the world. The third edition is particularly important because it describes the "Water Safety Framework" approach which stresses the complementary roles of the water industry, regulators and environmental protection agencies in the protection of drinking water quality.

For further information visit: http://www.who.int/water_sanitation_health/dwq/en/flyerguidelines3.pdf

15 September 2004

Draft Programme for the Conference on Water Contamination Emergencies: Enhancing our Response

9 August 2004

Observer claim that there are traces of Prozac in Drinking Water is incorrect

2 August 2004

Call for Papers for the Conference on Water Contamination Emergencies: Enhancing our Response

7 July 2004

Press Release on the Drinking Water 2003 report - Further improvements in tap water quality - Where do we go from here?

7 July 2004

Water Quality in your area