DWI Information Letter 12/2002
2 September 2002
To : Board Level and Day to Day Contacts in Water Service Companies and Water Companies in England and Wales
Dear Sir/Madam
CRYPTOSORIDIUM IN WATER SUPPLIES: MONITORING DATA AND ANOMALY REPORTING FOR THE WATER SUPPLY (WATER QUALITY) REGULATIONS 2000 (ENGLAND) AND WATER SUPPLY (WATER QUALITY) REGULATIONS 2001 (WALES)
Purpose
The purpose of this letter is to advise companies of changes to the:
notification of Cryptosporidium anomalies to the Inspectorate; and
Inspectorate's procedure for reporting the outcome of investigations of anomalies.
Introduction
Information Letters (IL) 10/1999, 4/2000, 10/2000, 13/2000 and 28/2000 set out the arrangements for water companies to report to the Inspectorate the results of analysis of regulatory Cryptosporidium sampling. Operational data needs to be reported as a separate file as specified in Information Letter 10/2000 and is not subjected to data checks.
IL 8/2001 gave water companies advice on the checks that the Inspectorate carries out on the regulatory Cryptosporidium monitoring data and clarified the requirements for the retention of information. In addition, the Inspectorate sought water companies’ views on proposed changes to the ways in which monitoring data and anomalies are reported to the Inspectorate.
This Information Letter sets out the revised arrangements for the recording and reporting of anomalies which will come into effect on 1 October 2002. The Inspectorate is currently engaged in designing an Access97 database which will be used to report water companies’ operational and compliance Cryptosporidium monitoring data in the future. Until this database design has been completed the current arrangements for reporting data, detailed in IL 4/2000, will remain in place with the exception of the addition of a field to allow the inclusion of a unique anomaly reference number.
Monitoring data returns
Formatting and data errors
IL 8/2001 detailed the checks on data format and integrity that the Inspectorate carries out on the regulatory Cryptosporidium monitoring data. Electronic versions of the formulas and queries used to check these data are available on request from Tony Hallas, (020 7944 5983, e-mail: tony.hallas@defra.gsi.gov.uk). It is expected that water companies will wish to carry out their own checks on the format and integrity of their data prior to submission although the Inspectorate will continue to undertake its checks. Should formatting errors be detected in the data, the Company concerned will receive a letter notifying it of the errors and requesting correction and resubmission within fourteen days.
When complete and accurate data are received the Inspectorate will carry out further checks on the data to identify any unreported breaches of the regulations or other important anomalies.
Operational data
Operational data will not be submitted to format or integrity checks but should be submitted in a separate Excel97 workbook. The data should be in exactly the same format as the regulatory data although some fields where there is no data should be left blank.
Changes to the reporting of monitoring data by companies
At present a number of data format or integrity errors are identified during data checking. These are the result of anomalies that have been notified but not readily recognised because there is no cross referencing system. Similarly, there are a number of events notified under the anomaly recording system which are identified as a result of data checks. In order to facilitate the cross referencing of these matters an additional field has been added to the current data return to allow the recording of anomaly reference numbers. The revised Excel97 format for monthly data returns is shown in Appendix A. Electronic copies are available from Tony Hallas, contact details as in paragraph 5 above. The current comments field should be used to record appropriate comments and information relating to failed checks.
Changes to the taking and recording of start/finish readings
A number of failed data checks have arisen as a result of the sampler failing to take readings at the correct time. Water companies were provided with details of the correct time to take readings in Appendix B of IL 8/2001. For ease of reference Appendix B is reproduced with this letter. Part 1 of the Standard Operating Protocol will be amended to reflect this guidance at its next revision.
Changes to the notification of anomalies by companies
Under existing arrangements, companies do not know the reference number the Inspectorate allots to an anomaly. The Inspectorate has concluded that, in order to make other cross checks easier, from 1 October 2002, companies must include in the notification of the anomaly, the reference number, the evidence bag number(s) and the affected sample number(s). The notification (Appendix C) and report (Appendix D) pro-forma have been amended to allow the reference number and evidence bag numbers to be included.
The format for the anomaly reference is xxx/yy/mm/nnn where:
xxx is the company identification (see Appendix J for the Company reference number)
yy is the year in which the anomaly occurred eg 02 for 2002
mm is the month in which the anomaly occurred eg 01 for January
nnn is a sequential number assigned by the company, restarting at one for the first anomaly each month.
The Inspectorate has also concluded that it would be more effective to revise the way in which anomalies are reported. The changes to reporting anomalies in relation to sample lines, sampling cabinets, control/display cabinets, maintenance and repairs are detailed in Appendix E. These changes replace the requirement for anomaly notification of routine sampling equipment repairs, maintenance and tagging with a system of sample unit log books. All sampling units will be required to have their own tag log from 1 October 2002. Companies will be responsible for maintaining the log which will demonstrate continued chain of evidence and be subject to periodic inspection by the Inspectorate. An example of a suggested format for a page from a sampling unit log book is included in Appendix F.
The Inspectorate has concluded that a shortened revised list of anomaly notification codes should be used from 1 October 2002. A list of the proposed new anomaly codes and notification requirements are given in Appendices G and H. A comparison with the current arrangements is given in Appendix I for ease of reference.
Changes to the reporting of the Inspectorate’s assessment of investigations of Cryptosporidium anomalies
A significant number of anomalies have been caused by maintenance work being carried out on sampling units at inappropriate times. All maintenance work on sampling units should be undertaken during the one hour sample changeover period. This extended period was specifically written into the Regulations to allow maintenance work to be carried out. Apart from maintenance work overrunning due to unforeseen problems, the only exceptions are emergency work required to:
restore Cryptosporidium sampling following loss of sampling; or
address an immediate health and safety issue.
As an alternative to scheduling maintenance to coincide with sampling, there is also leeway in the Regulations for a company to retime sampling to coincide with maintenance work.
The Inspectorate has previously provided a report of the outcome of its investigation of each reported anomaly. More recently it has adopted a system of exception reporting. The Inspectorate will continue to request further information relating to an anomaly whenever this is required, but will only produce a report if it has a recommendation or other relevant comment to make on individual assessments.
However, from October 2002 the Inspectorate will provide companies with periodic statements indicating the status of anomaly reports and, by exception, any anomaly report which is still under consideration within a specified period.
Retention of records
Paragraph 3.5.1 of Part 1 of the Standard Operating Protocol specifies that all documentation and receipts must be kept in a secure location for a minimum period of twelve calendar months following sampling. This applies to all documents associated with the sample. On rare occasions it may be necessary to retain the records relating to a specific sample for longer. The Inspectorate will notify a company in writing when this is the case. Such records must be stored under secure conditions until written authorisation is given by the Inspectorate for their disposal. The requirement to retain records for one year is in addition to the requirement to retain information entered on the public record.
Notification
Notification of high priority anomalies (see Appendix H) should be made to Tony Hallas (020 7944 5983) or Peter Marsden (020 7944 5975). Outside of normal working hours, please use the cascade contact arrangements for notification of incidents in the Defra Water and Land Directorate Emergency Telephone Directory.
Enquiries
Any enquiries about this letter should be addressed to David Drury (020 7944 5976) or Tony Hallas.
This letter is being sent electronically to board level and day-to-day contacts. Please acknowledge its receipt by e-mail to dwi.enquiries@defra.gsi.gov.uk. Hard copies are not being sent. This letter may be freely copied.
Copies of this letter and the attachments are being sent to Pamela Taylor, Chief Executive, Water UK; Rodney Anderson, Water Supply and Regulation Division, Department of the Environment, Transport and the Regions; Bob Macey, Environment Division, The National Assembly for Wales; Tim Hooton, Water Services Unit, Scottish Executive; Randal Scott, Drinking Water Inspectorate for Northern Ireland; Rowena Tye, Office of Water Services and Ailsa Wight, Department of Health.
Yours faithfully
Michael Rouse
Chief Inspector
The following documents are available in Adobe Acrobat format for download. The Adobe Acrobat Reader can be freely downloaded.
Appendix A Appendix B Appendix C Appendix D Appendix E Appendix F Appendix G Appendix H Appendix I Appendix J
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Published 11 September 2002
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