DWQR Annual Report 2005
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Drinking Water Quality in Scotland 2005 Drinking Water Drinking Water Quality in Scotland 2005 Annual Report by the Drinking Water Quality Regulator Annual Report by the Drinking Water Quality Regulator Annual Report by the Drinking Water © Crown copyright 2006 This document is also available on the DWQR website: www.dwqr.org.uk Astron B46660 08/06 Further copies are available from Blackwells Bookshop 53 South Bridge Edinburgh EH1 1YS Telephone orders and enquiries 0131 622 8283 or 0131 622 8258 Fax orders 0131 557 8149 Email orders [email protected] ISBN 0-7559-5077-1 9 780755 950775 www.dwqr.org.uk Drinking Water Quality in Scotland 2005 Annual Report by the Drinking Water Quality Regulator Drinking Water Quality in Scotland 2005 © Crown copyright 2006 Published on behalf of the Drinking Water Quality Regulator for Scotland, August, 2006 ISBN: 0-7559-5077-1 Produced for the Drinking Water Quality Regulator by Astron B46660 08/06 Further copies are available from Blackwell's Bookshop 53 South Bridge Edinburgh EH1 1YS The text pages of this document are printed on recycled paper and are 100% recyclable Drinking Water Quality in Scotland 2005 Contents 1. Foreword 1 2. Executive Summary 3 3. Introduction 7 4. Drinking Water Quality across Scotland 15 4A. Public Water Supplies in Scotland 17 4B. Private Water Supplies in Scotland 37 5. Drinking Water Quality by Region 43 5.1 Regional Key Facts 45 5.2 Drinking Water Quality in the South West 47 5.3 Drinking Water Quality in the North West 51 5.4 Drinking Water Quality in the North East 55 5.5 Drinking Water Quality in the South East 59 5.6 Drinking Water Quality in the Western Isles, Orkney Islands and Shetland 62 6. Local Authority Pages 69 Annex A: The Regulatory Framework 141 Annex B: Index of Information Letters/Guidance Letters issued during 2005 143 Annex C: Authorised Departures 144 Annex D: Other Key Activities Undertaken on Behalf of the DWQR in 2005 146 Annex E: Statistical Methods Used in the Report 148 iii iv Drinking Water Quality in Scotland 2005 Foreword This is my first drinking water quality report year. In 2005, 99.56% of all tests carried out on since being appointed as Drinking Water water samples taken from consumers’ taps Quality Regulator for Scotland in September complied with the relevant standard. This 2005. Prior to being appointed, I worked compares with 99.42% in 2004. At a national closely with my predecessor, Tim Hooton, for a level, there have been some notable number of years and hope to carry on his good improvements in compliance with the standards work. Tim was instrumental in driving forward set for trihalomethanes, colour and pH. significant improvements in drinking water However, the overall compliance figure masks a quality over the last decade or so, such that the deterioration in the level of microbiological overall quality of the public supply in Scotland compliance. In 2005, 0.97% of microbiological is now very high. I intend to build on these tests on samples taken from consumers’ taps improvements and start to address some of the contained coliforms; this compares with 0.88% local issues that lie behind the overall picture in 2004. The microbiological standards are of improving water quality. important as they may indicate a breach in the integrity of the water supply system or a failure I want to raise awareness about the quality of of the treatment process. Any microbiological drinking water in Scotland and make water failure requires to be investigated. I am quality data more accessible to the public. To concerned therefore that the longstanding trend help achieve this, I intend to update the DWQR of improving microbiological compliance may website (www.dwqr.org.uk) to provide the have come to an end in 2005. I look to Scottish public with access to local drinking water Water to make sure that this is not the case. quality data. I have also made some changes to the format of this report and expanded the In 2005, 42 of the water quality events notified information provided on water quality at a to me by Scottish Water were sufficiently regional and local level, as well as including serious to be classified as incidents that merited more information on private water supplies and further investigation. This represents an consumer complaints. increase of 14 on the previous year. Twenty- five of the 42 incidents involved The drinking water quality data for 2005 shows microbiological sample failures or failures of that overall, compliance with the drinking the disinfection process during treatment. water quality standards improved during the 1 1. Foreword Disinfection failures at treatment works should Finally, I would like to express my support for be minimised through maintenance of the strengthened Private Water Supply equipment and robust operating procedures. Regulations which came into force in July Any that do occur, if responded to quickly, 2006. These provide a practical means for should not result in microbiological failures at ensuring the safety of private water supplies customers’ taps. Although Scottish Water has and should minimise the risk to the users of done much to improve its alarm and telemetry such supplies. systems, which allow a quick response to be made to such failures, I believe that more needs I hope that you will find this report to be done. In particular, Scottish Water needs comprehensive and informative, whether you to make sure that it learns from incidents when read it in its entirety or study particular they occur and that the lessons learned are sections of interest. disseminated across the business. I am watching the situation closely to ensure that Scottish Water gives sufficient priority to this most fundamental part of the water treatment process and that it is learning from any incidents. Colin McLaren In addition to the incidents mentioned, there Drinking Water Quality Regulator for Scotland were two high-profile instances in 2005 when consumers were dissatisfied with the taste and August 2006 odour of the public water supply. One of these instances occurred in relation to Calder on the North Coast and the other was in relation to the public supply in Strathdon, Aberdeenshire. I have no doubt that in both instances the water remained safe to drink, but these incidents serve to highlight that Scottish Water must provide water that is not only safe but also acceptable to consumers. In this regard, I now routinely receive data from Scottish Water on the customer complaints relating to drinking water quality. In this report I have used the data from complaints and regulatory sampling to help identify some local water quality issues. I intend to continue to use this type of data to help identify more of these issues. 2 Drinking Water Quality in Scotland 2005 2. Executive Summary 3 2. Executive Summary 4 Drinking Water Quality in Scotland 2005 2. Executive Summary The drinking water quality results reported by Figure 2.1 Number of Microbiological Tests on Scottish Water for 2005 show that 345,761 tests Tap Samples Containing Coliforms were carried out on samples taken from water and Faecal Coliforms treatment works, service reservoirs and 1800 consumer taps. Of the 153,291 tests on samples Coliforms 1600 Faecal Coliforms taken from consumer taps, 99.56% met the 1400 required standard. This is an increase of 0.14% 1200 on compliance for 2004. A total of 669 tests 1000 800 gave results which did not meet the standard 600 set out in the Water Supply (Water Quality) 400 and Faecal Coliforms (Scotland) Regulations 2001. The largest 200 No. of Failures for Coliforms 0 number of fails were for the total coliform and 1991 1993 1995 1997 1999 2001 2003 2005 trihalomethane parameters. Year Compliance for the key microbiological Extensive sampling of raw and final waters for parameters was slightly worse than in 2004. Cryptosporidium was undertaken in 2005 in The 138 failures of the coliform standard at accordance with the Cryptosporidium (Scottish customers’ taps in 2005, (0.97% of samples), Water) Directions 2003. A total of 13,186 raw compares unfavourably with 123 failures in and final samples were taken from 296 water 2004 and 135 in 2003. The number of faecal treatment works, of the final water samples, coliform (E. coli) failures also increased slightly 728 contained Cryptosporidium oocysts. from 18 in 2004 to 21 in 2005. Although small this trend is disappointing. Undoubtedly, the DWQR receives details from Scottish Water of number of water quality incidents reported in events which could affect drinking water quality. 2005 that involved failure of the disinfection In 2005, 42 such events were considered process will have been a contributing factor. It sufficiently serious to be classified as incidents. is expected that the general improving trend in Where appropriate, DWQR investigated the the microbiological quality of drinking water in circumstances of these incidents and made Scotland will continue and DWQR is recommendations. A summary of the findings monitoring this situation very closely. Data may be found on the DWQR website, going back to the year 1991 are shown in www.dwqr.org.uk Figure 2.1, and these clearly show the 2005 results in the context of those of the previous 14 years. 5 6 Drinking Water Quality in Scotland 2005 3. Introduction 7 3. Introduction 8 Drinking Water Quality in Scotland 2005 3. Introduction 3.1 Role of the Regulator Wales. In Scotland the DWQR is responsible for The quality of drinking water in Scotland is enforcing The Water Supply (Water Quality) regulated by the Drinking Water Quality (Scotland) Regulations independently of Regulator for Scotland (DWQR).