rnigWtrQaiyi ctad20 nulRpr yteDikn ae ult Regulator Quality Water Drinking the by Report Annual 2007 Scotland in Quality Water Drinking I am concerned about the quality of my drinking water in my home or Drinking Water place of work. What can I do? Quality in Scotland 2007 Annual Report by the Drinking Water Quality Regulator In the first instance you should contact Scottish Water and ask them to investigate.

Scottish Water PO Box 8855 Edinburgh EH10 6YQ

Tel 0845 601 8855

If, having discussed the matter with Scottish Water, you do not feel that the issue has been satisfactorily resolved, you should contact the Drinking Water Quality Regulator for Scotland. The DWQR can investigate on your behalf and take action if necessary. DWQR will inform you of the outcome of any investigation.

The DWQR may be contacted either by writing to:

Drinking Water Quality Regulator for Scotland PO Box 23598 EDINBURGH © Crown copyright 2008 EH6 6WW This document is also available on www.dwqr.org.uk Or emailing [email protected] RR Donnelley B56313 07/08 Or telephoning 0131 244 0224 Further copies are available from When contacting DWQR, please provide as much information as possible, including the Blackwell's Bookshop address of the property where the problem has occurred, the nature and duration of your 53 South Bridge concerns and details of any contact you have had with Scottish Water regarding the problem. Edinburgh Please note that the DWQR can only investigate concerns relating to the quality of public EH1 1YS drinking water supplies in Scotland. For matters concerning private supplies in Scotland you should contact the Environmental Health Department of your local council. Telephone orders and enquiries 0131 622 8283 or 0131 622 8258 For matters concerning services provided by Scottish Water other than the quality of the water supplied you should contact Waterwatch Scotland: [email protected] Fax orders 0131 557 8149 For matters concerning the quality of public supplies elsewhere in the UK you should contact the Drinking Water Inspectorate (DWI) for England or Wales or the Northern Ireland Drinking Email orders Water Inspectorate. The DWQR works closely with both of these organisations to ensure a [email protected] consistent approach is taken towards ensuring the quality of drinking water across the UK. A Memorandum of Understanding between the three bodies can be found on the DWQR website: www.dwqr.org.uk

www.dwqr.org.uk Drinking Water Quality in Scotland 2007

Annual Report by the Drinking Water Quality Regulator Drinking Water Quality in Scotland 2007

© Crown copyright 2008

The maps presented in this publication are based on Ordnance Survey material with the permission of Ordnance Survey on behalf of the Controller of Her Majesty’s Stationery Office © Crown copyright 2008. Unauthorised reproduction infringes Crown copyright and may lead to prosecution or civil proceedings. Scottish Government Licence number: 100020540, 2008.

Published on behalf of the Drinking Water Quality Regulator for Scotland, August, 2008

ISBN: 978 0 7559 5785 9

Produced for the Drinking Water Quality Regulator by RR Donnelley B56313 08/08

Further copies are available from Blackwell's Bookshop 53 South Bridge Edinburgh EH1 1YS

The text pages of this document are printed on 100% recyclable paper Drinking Water Quality in Scotland 2007

Contents

1. Foreword 1 2. Executive Summary 4 3. Drinking Water Quality Across Scotland 7 3A Public Water Supplies in Scotland 8 3.1 Quality of Drinking Water Sources 11 3.2 Drinking Water Quality at Treatment Works 13 3.3 Drinking Water Quality in Distribution Systems 17 3.4 Drinking Water Quality at Consumer Taps 22 3.5 Summary of Drinking Water Quality Events and Incidents 28 3.6 Summary of Contacts About Drinking Water Quality 32

3B Private Water Supplies in Scotland 37

4. Drinking Water Quality by Region 41 4.1 South West 44 Water Quality in Local Authorities in the South West 51 4.2 North West 64 Water Quality in Local Authorities in the North West 83 4.3 North East 87 Water Quality in Local Authorities in the North East 94 4.4 South East 100 Water Quality in Local Authorities in the South East 106 4.5 Islands 113 Water Quality in Local Authorities in the Islands 119

Annexes 122 A The Regulatory Framework 123 B Index of Information Letters and Guidance Letters 126 C Authorised Departures 127 D Audits of Scottish Water 129 E Statistical Methods Used in the Report 132 Drinking Water Quality in Scotland 2007

Drinking Water Quality in Scotland 2007

Foreword

1. Foreword

I am pleased to report that in 2007, the treatment works failed to adequately overall level of compliance of Scottish treat raw water that was deteriorating in drinking water with the regulatory quality due to heavy rainfall. standards was higher than ever. Communities such as Ullapool, Consumers can therefore be confident Langholm, Tomintoul and North that public drinking water supplies in Ronaldsay all faced the inconvenience of Scotland are of the highest quality and prolonged, and in some cases repeated, Scottish Water can justifiably be proud boil water notices following the of what it has achieved since it was detection of Cryptosporidium in the formed six years ago. supply. I firmly believe that such situations are unacceptable in 21st However, there is no room for century Scotland. This view is shared complacency. Against this encouraging by Consultants in Public Health Medicine background, work is still required to and local authority Environmental further improve compliance with the Health Officers who have expressed trihalomethane and microbiological their concerns to me. The Summer of standards. Compliance with the 2007 was exceptionally wet but high manganese standard also requires rainfall events are not unusual in further work. Manganese causes Scotland, and treatment facilities must discoloured water, which can give rise be sufficiently robust to deal with to “dirty” water complaints from changes in raw water quality. consumers. This is an area that I highlighted in last years annual report, Plans are being developed to improve and while it is encouraging that there treatment at the above sites, and in were fewer customer contacts about most cases temporary treatment has dirty water in 2007, it is disappointing been put in place until a long term that compliance with the manganese solution can be delivered. I am standard itself did not improve. continually frustrated however by the time taken to deliver such much needed Scottish Water continues to invest improvements and look to Scottish considerable resources in improving Water to find a way within the drinking water quality, and that investment process to progress these investment appears to be delivering projects with the urgency they demand. benefits. However, improvements to drinking water assets need to be Scottish Water has a large volume of sustained, so looking forward, it is water quality data at its fingertips, important that Scottish Water ensures together with the expertise to appropriate resources are directed understand and interpret it. I would like towards maintaining its assets, to to see Scottish Water taking more ensure that they are able to perform responsibility for identifying and effectively for many years to come. managing risk in its supply systems so that timely corrective action can be The low point of 2007 occurred in taken to ensure that good safe drinking August when a number of Scottish water is consistently supplied to

1 Drinking Water Quality in Scotland 2007

Foreword

consumers. This is fundamental to the I am pleased that the number of Drinking Water Safety Plan approach to consumer contacts relating to concerns safeguarding water systems promoted about drinking water quality reduced in by the World Health Organisation and I 2007. I hope that this is a genuine am encouraged that Scottish Water has trend that will continue in 2008. I am embarked on production of these plans aware however, of a number of local with enthusiasm and dedication. issues where communities have very genuine concerns over the appearance For a number of years I have been and/or taste of their drinking water. expressing concern over a lack of Improvements in regulatory compliance robustness in the on-site water quality count for nothing if consumers find the instrumentation and telemetry systems aesthetic characteristics of their water that alert Scottish Water to problems at unacceptable and refuse to drink it. water treatment works. I was therefore keeping a close eye on this during 2007 Consumer acceptance and trust in and am pleased to report that Scottish drinking water supplies is achieved Water is well advanced with a where Scottish Water consistently programme of testing and upgrading its delivers a high quality product. Lack of monitoring systems. I am increasingly acceptance and trust often relates to satisfied that Scottish Water is the level of chlorine in the supply. responding appropriately to water Chlorine in various forms is used quality alarms, which means that throughout the world as it is one of the potentially difficult situations are being most effective means of disinfecting resolved before public health is put at water supplies and providing lasting risk. While the number of occasions protection throughout the distribution that the system did not work in 2007 system. Scottish Water must ensure was still unacceptably high, I am that when it is disinfecting its supplies confident that steps are finally being that this is carried out in a way that is taken in the right direction. acceptable to consumers, while at the same time safeguarding public health. In my role as Regulator, it is important that I monitor all aspects of Scottish Finally, in addition to regulating public Water’s activities that could affect supplies, I have a role overseeing the drinking water quality. With this in quality of the private supplies in mind, I introduced two new types of Scotland. About 3% of Scotland’s audits in 2007 – (i) work on distribution population and countless visitors rely on systems; and (ii) handling of consumer private water supplies for their drinking contacts relating to water quality. Both water. Responsibility for regulating of these audits were useful in identifying these supplies rests directly with local areas for improvement and I am authorities, and they have been tasked working with Scottish Water to ensure with risk assessing all private supplies that these are adequately addressed. I that (a) provide more than 10 cubic propose to repeat these audits in order metres of water per day, (b) serve more to confirm that the necessary than 50 people, or (c) regardless of the improvements have been made. volume supplied or the number of persons served are used as part of a

2 Drinking Water Quality in Scotland 2007

Foreword

commercial or public activity. I believe that some of these supplies have the potential to present a considerable risk to public health and that it is vital that the work to assess them under the Private Water Supplies (Scotland) Regulations 2006 is carried out as quickly as possible. This will enable the person that is responsible for these supplies to be fully aware of the risks and to take the appropriate action. Scottish Ministers have set up a grant scheme to assist with improvements to private water supplies.

Colin McLaren Drinking Water Quality Regulator August 2008

3 2. Executive Summary

4 Drinking Water Quality in Scotland 2007

Executive Summary

2. Executive Summary

This is the sixth annual report prepared Compliance with the key microbiological by the Drinking Water Quality Regulator parameters continued to improve in for Scotland (DWQR) and submitted to 2007. There were 78 failures of the Scottish Ministers. It presents and coliform bacteria standard at consumers' reviews the information provided by taps and 5 samples contained E.coli, Scottish Water under the Water Supply comparing favourably with 114 and 9 (Water Quality) (Scotland) Regulations respectively in 2006. Data going back 2001 (the Regulations) and reflects the to 2002, when Scottish Water was dealings that the DWQR had with formed, are shown in Figure 2.1. These Scottish Water between 1 January and clearly show the improvement in 31 December 2007. The report also microbiology results. presents and reviews information on private supplies provided by the Local Figure 2.1 Summary of Microbiological Authorities. Section 3 of this report Tests on Tap Samples Since 2002 covers drinking water quality at a national level, examining the water 250 quality in sources, at water treatment Total Coliforms

works, and through the distribution E.coli E.coli 200 system to consumers’ taps. Section 4

breaks the national picture down into 150 the five regions of Scotland represented by the Waterwatch Scotland panel 100 areas, and provides details of water 50 quality at consumers’ taps by local

authority area. Failures for Coliforms and 0 2002 2003 2004 2005 2006 2007 The drinking water quality results reported by Scottish Water for 2007 Extensive sampling of raw and final show that 363,451 tests were carried waters for Cryptosporidium was out on samples taken from water undertaken in 2007 in accordance with treatment works, service reservoirs and the Cryptosporidium (Scottish Water) consumer taps. Of the 160,601 tests on Directions 2003. Final Water samples samples taken from consumer taps, were taken from 300 water treatment 99.76% complied with requirements for works, providing 11,393 samples which there is a numerical standard, an throughout the year. Of these samples, improvement on 2006. A total of 393 927 (8.1%) contained Cryptosporidium tests gave results which did not meet oocysts, a slight increase on 2006. the standard set out in the Water Supply (Water Quality)(Scotland) DWQR receives details from Scottish Regulations 2001. As in previous years, Water of events which could affect the largest number of failing samples drinking water quality. In 2007, 64 out was for the total coliform and of 1,407 water quality events notified to trihalomethane parameters. DWQR were classified as incidents and

5 Drinking Water Quality in Scotland 2007

Executive Summary

investigated. The exceptionally wet Summer resulted in a number of boil water notices being imposed following detection of Cryptosporidium oocysts at locations where the treatment process was not adequate to deal with the deterioration in source water quality.

In 2007, Scottish Water was contacted 26,702 times by consumers concerned about drinking water quality issues. This represented a reduction of 16% on 2006. The largest category of contacts (37.4%) concerned discoloured supplies.

6 3. Drinking Water Quality Across Scotland

7 Drinking Water Quality in Scotland 2007 Scotland

3. Drinking Water Quality Across Scotland

3A Public Water Supplies in Scotland

Table 3A Key Facts - A Summary of Drinking Water Assets in Scotland

Raw Water Sources Source Type Lochs and Reservoirs Rivers and Burns Springs and Boreholes TOTAL Number of Sources 227 218 89 534 Treatment Works Volume of Water Distributed (Ml/d) <2 2 to 10 >10 TOTAL Number of Treatment Works 213 54 40 307 Daily Supply (Ml/d) 61 263 2,206 2,530 Storage Points Capacity of Reservoir (Ml) <2 2 to 10 >10 TOTAL Number of Storage Points 849 194 45 1,088 Capacity (Ml)* 316 866 1,274 2,456 Distribution Network Diameter of pipe <150mm 150-300mm >300mm TOTAL Length of Mains (Km) 29,723 12,176 5,264 47,163 Supply Zones Size of Zone (Population) < 5,000 5,000 to 20,000 > 20,000 TOTAL Number of Zones 224 48 82 354 Population 152,173 510,861 4,326,355 4,989,389 Public water supplies in Scotland are the zones. In 2007 there were 354 public responsibility of Scottish Water. The water supply zones in Scotland. The majority are derived from surface water number of treatment works and supply sources, although an increasing number of zones in Scotland has been steadily groundwater sources are being used. decreasing as Scottish Water and its Water from all of these sources is treated predecessors have developed regional at 307 treatment works before being schemes to replace many of the smaller distributed through 1,088 service supplies, improving efficiency and the reservoirs and over 47,000km of mains. quality of water supplied. Notably, in On average, about 2,530 Megalitres (Ml) 2007 the small treatment works on the of potable water is supplied each day to shores of Loch Alsh and Loch Duich were about 97% of the resident population. closed, and the population previously The remainder of the population are served by these works became part of a served by private supplies, which are larger single supply zone supplied from described in section 3B of this report. the modern works at Kyle of Lochalsh. The maximum population allowed in a The area served by the public water single water supply zone is 100,000. supply system is split into water supply

8 Drinking Water Quality in Scotland 2007 Scotland

Assessment of Water Quality Ten key drinking water quality standards Compliance have been identified from the 2001 Regulations that are of particular The Water Supply (Water Quality) significance when considering the quality (Scotland) Regulations 2001 set out the of drinking water in Scotland. Definitions number of samples that have to be taken of these Ten Key Parameters may be by Scottish Water from each water found on the fold out flap at the back of treatment works, service reservoir and this report. water supply zone every year. The majority of samples in water supply zones In contrast to the 1990 Regulations that are taken from randomly selected they replaced, the 2001 Regulations do consumer taps. The Drinking Water not enable Scottish Ministers to authorise Quality Regulator expects full compliance the relaxation of a PCV. However, where with the sampling frequencies specified in a non-trivial exceedence of a Schedule 1 the 2001 Regulations. Circumstances parameter occurs, Scottish Water can outwith Scottish Water’s control can apply for an Authorised Departure. This occasionally prevent samples from being allows for a temporary departure from the taken, but over-sampling is not allowed. standard while work is undertaken to In practice, each sample may be tested secure compliance with the Regulations. for several parameters so the text and the This process is described in full in tables relate to the number of Annex C. determinations (tests) made for each It is important to note that the PCV’s for individual parameter rather than to the parameters that are of health significance number of samples taken. are based on World Health Organisation Schedule 1 of the 2001 Regulations sets a (WHO) guidelines and that they are set prescribed concentration or value (PCV) with a wide margin of safety. For for 40 parameters. In general, to be parameters that are of aesthetic wholesome, water must not contain a significance, the standards are generally parameter in excess of a PCV; in the case set well below the level at which water of the Hydrogen Ion parameter (pH) the would become unacceptable to value must lie in a range defined by a consumers. A contravention of a standard maximum and minimum prescribed value. therefore is not necessarily indicative that Schedule 2 of the Regulations sets values the water is unfit to drink or represents a for a further 11 “indicator” parameters. risk to health. These are not part of the definition of However, a contravention of a PCV is of wholesomeness unless a breach of the significance because it means that the standard constitutes a risk to health. water supplied at the time the sample was Scottish Water is required to investigate taken cannot be regarded as wholesome any exceedences of Schedule 1 or as defined by the Regulations. When a Schedule 2 parameters. contravention is considered in conjunction

9 Drinking Water Quality in Scotland 2007 Scotland with other monitoring results, it may Overall Compliance indicate that work is necessary in order to The drinking water quality results reported meet the high standards set in the by Scottish Water for 2007 show that Regulations. When interpreting some 363,451 tests were carried out on samples contraventions of samples taken from a taken from water treatment works, service consumer’s tap, especially those for lead reservoirs and consumer taps. Of the and microbiological parameters, it is 160,601 tests on samples taken from important to remember that the result consumers’ taps, 99.76% complied with may reflect the condition of the tap or the requirements for which there is a plumbing in the property rather than the numerical standard. A total of 393 tests water in the public supply. The gave results which did not meet the circumstances under which water is stored standard set out in the 2001 Regulations. within a building can also greatly affect its As in previous years, the largest number quality. of failing samples was for the total The general rule that any individual coliform and trihalomethane parameters. contravention of a PCV constitutes a Further details may be found in Section breach of Schedule 1 of the Regulations 3.4. and thus causes the water to be regarded as unwholesome, does not apply to the coliform standard at service reservoirs. Regulation 4(6) requires that 95% or more of tests from a Service Reservoir, carried out over the preceding year, meet the coliform standard.

In addition to absolute PCVs for nitrite and nitrate, Regulation 4(d) specifies an additional requirement reflecting the combined concentration of the two parameters, namely that the water satisfies the formula:

[nitrate]/50 +[nitrite]/3 <1 where the square brackets refer to the concentration of the two compounds in milligrammes per litre (mg/l). An assessment of compliance with this formula shows that this standard was not breached in 2007.

10 Drinking Water Quality in Scotland 2007 Scotland

3.1 Quality of Drinking Water Sources

Table 3.1-a Summary of Data from Sampling of Water Sources

Parameter name No. test Min. test Max. test Ave. test results result result result Coliform Bacteria CFU per 100ml 113 0 2,010 70.99 E. coli CFU per 100ml 113 0 1,450 36.98 Enterococci CFU per 100ml 152 0 100 4.13 Colour mg/l Pt/Co 332 2 281 46.75 Hydrogen ion pH value 332 4.40 9 7.16 Manganese mg/l 268 1 7,367 67.96 Ammonium mgNH4/l 332 0.03 0.26 0.05 Nitrate mgNO3/l 331 0.30 25.70 1.39 Pesticides - Total mg/l 371 0 0.32 0

The 2001 Regulations do not require of raw water quality likely to be Scottish Water to sample its water encountered by that works. sources, although in 2007 sampling did Some substances, such as manganese, take place for operational reasons and to are naturally occurring, while others, like comply with the EU Surface Water nitrate and pesticides are present because Abstraction Directive (SWAD). Table 3.1-a of agricultural activity. It can be shows a summary of selected results from expensive to remove nitrate and pesticide tests carried out on samples taken during from the water – fortunately they are not 2007 from water sources used for public present in many Scottish sources because drinking water supplies. The data is a most sources in Scotland are derived from combined summary of all the sources that upland catchments where agricultural were sampled (mainly reservoirs and activity is limited. lochs). It provides an indication of the range of waters Scottish Water normally Many raw sources contain significant has to treat in order to comply with the numbers of bacteria, which serves to standards set down in the 2001 demonstrate the importance of adequate Regulations. treatment, including disinfection, in order to make the water safe to drink. Water quality can vary considerably between sources but quality can also vary The EU Surface Water Abstraction with time, especially during severe Directive has now been repealed and weather. Scottish Water must therefore arrangements have been put in place with ensure that its treatment works have the Scottish Water to ensure that sampling of processes necessary to reliably produce raw waters continues under the Water clean, safe drinking water from the range Framework Directive.

11 Drinking Water Quality in Scotland 2007 Scotland

Table 3.1-b Source Water Cryptosporidium Data

Number of Number of Raw Max. oocyst Ave. oocyst Treatment Works Region Positive Raw Source Samples count per 10l count per 10l Source Samples Dodburn WTW South East 25 6 5.45 0.52 Forehill WTW North East 44 15 3.58 0.35 Alexandria WTW South West 12 9 1.98 0.31 Glenfarg WTW North East 26 5 4.26 0.30 Westray WTW Islands 12 2 1.73 0.26 Tweedsmuir WTW South East 175 94 7.30 0.17 Turriff WTW North East 52 26 1.79 0.13 Glassford WTW South West 12 5 0.78 0.12 Craighead WTW North East 26 7 0.56 0.09 Glendye WTW North East 26 10 0.52 0.09 Scotland 2,139 586 7.30 0.06

The Cryptosporidium (Scottish Water) 2007. Table 3.1-b shows a summary of Directions 2003 require Scottish Water to the data for the whole of Scotland and sample all drinking water sources that lists the ten sites with the highest average have been designated as high risk for count of Cryptosporidium oocysts in Cryptosporidium. In 2007, a total of 78 source water samples. As in 2006, drinking water sources were sampled Dodburn near Hawick and Forehill across Scotland. Positive Cryptosporidium supplying Peterhead contained the highest samples were found at all but 19 of these average oocyst count in raw samples. An sites. In 2007, 27.4% of raw water appropriate, well-optimised treatment samples contained oocysts – the process should minimise the risk of corresponding figure for 2006 was 24%; Cryptosporidium oocysts being present in the increasing percentage perhaps the final water. reflecting the wetter Summer weather in

12 Drinking Water Quality in Scotland 2007 Scotland

3.2 Drinking Water Quality at Treatment Works

Table 3.2-a Microbiological Tests on Samples taken at Water Treatment Works and Comparison with Previous Years

Coliforms 2007 2006 2005 2004 2003 2002 2001 Standard = 0 per 100ml Number of tests 32,534 32,935 33,623 34,524 35,325 39,584 39,230 Number containing coliforms 33 70 130 118 108 131 111 Percentage containing coliforms 0.10 0.21 0.38 0.34 0.30 0.33 0.28 E.coli (Faecal coliforms) Standard = 0 per 100ml Number of tests 32,534 32,935 33,623 34,524 35,325 39,584 39,230 Number containing faecal coliforms 10 24 51 54 59 75 63 Percentage containing faecal coliforms 0.03 0.07 0.15 0.16 0.17 0.19 0.16

The Regulations require that samples are In 2006, a number of large treatment taken from treatment works and tested works experienced more than one failure for a number of parameters. These but in 2007, there was no particular include microbiological parameters, in geographical pattern, although Alnwickhill order to confirm the effectiveness of the treatment works, which supplies parts of disinfection process, and turbidity and Edinburgh, generated four of the failures. nitrite, to demonstrate control of this and In 2007, 10 samples taken from treatment other treatment processes. Table 3.2-a works contained E.coli, a failure rate of shows summary results for tests carried 0.03% - less than half the rate of failure out for coliforms and E.coli on samples seen in 2006. Invercannie WTW, serving taken at treatment works in 2007. Thirty- Aberdeen, saw one sample containing three (0.10%) of the samples taken at E.coli in 2007, compared with 5 in 2006. treatment works contained coliforms. This Scottish Water has investigated the is a significant reduction on the preceding failures at Invercannie and concluded that year and represents the best compliance they were due to the location of the since regulatory sampling was introduced. sample tap rather than the quality of the To put this achievement in perspective, 10 water leaving the works. Arrangements years ago, the percentage of samples have been put in place to move the taken from treatment works (1997) that sample point. contained coliforms was 1.8%. Sixteen of the 33 failures occurred in the Summer months of June, July and August.

13 Drinking Water Quality in Scotland 2007 Scotland

Table 3.2-b Summary of Nitrite Tests on Samples taken at Water Treatment Works

Nitrite 2007 2006 2005 2004 Indicator Standard = 0.1mg/l at WTW Number of tests 3,182 3,375 3,434 3,135 Number of tests exceeding standard 3 9912 Percentage of tests exceeding standard 0.09 0.27 0.26 0.38 Number of treatment works not meeting regulatory requirements 2 592 % of treatment works not meeting regulatory requirements 0.65 1.60 2.69 0.55

Nitrite is a compound that can form when Table 3.2-b shows that in 2007, 3 samples there is an excess of ammonia in a supply. failed to meet the required standard for It is an indicator parameter in treated nitrite at treatment works of 0.1mg/l, water, and the standard was introduced in representing a failure rate of 0.09%. This order to monitor the effectiveness of the is an improvement on 2006. Two of the disinfection process, particularly where failures occurred at Backies in Highland, chloramination is used. the other was at Kirkmichael in Perthshire.

Table 3.2-c Summary of Turbidity Tests on Samples Taken at Water Treatment Works

Turbidity 2007 2006 2005 2004 Indicator Standard = 1 NTU at WTW Number of tests 8,514 8,812 8,970 11,071 Number of tests exceeding standard 71 78 112 131 Percentage of tests exceeding standard 0.83 0.89 1.25 1.18 Number of treatment works not meeting regulatory requirements 39 40 49 57 % of treatment works not meeting regulatory requirements 12.70 12.50 14.60 15.80

Turbidity (cloudiness) of treated water is these failures are undoubtedly due to the an important measurement because it can location of the sample tap at the provide an indication of how well the treatment works and the influence of lime treatment process is removing particulate added during the treatment process to matter (including Cryptosporidium). It control the pH of the water. It is also indicates the effectiveness of disappointing that Scottish Water has not disinfection because it is difficult to taken action to ensure that all sample adequately disinfect turbid waters. points are located sufficiently far downstream of any treatment process to Table 3.2-c shows that in 2007, 71 ensure that the samples taken are samples exceeded the turbidity standard representative of the water leaving the at water treatment works, representing treatment works and not impacted upon 0.83% of samples tested. A number of by the treatment process itself.

14 Drinking Water Quality in Scotland 2007 Scotland

Table 3.2-d Summary of Sample Data for Cryptosporidium in Final Water

Cryptosporidium 2007 2006 2005

Number of tests 11,393 10,602 10,691 Number of samples containing Cryptosporidium oocysts 927 667 728 % of samples containing Cryptosporidium oocysts 8.14 6.29 6.81 Number of treatment works sampled for Cryptosporidium 300 304 296 Number of treatment works with one or more samples containing oocysts 138 178 123 % of treatment works with one or more samples containing oocysts 46.00 58.55 41.55

Cryptosporidium is a microscopic oocysts from contaminating drinking water protozoan parasite that can live in the gut supplies. Under the requirements of the of humans and warm blooded animals. Cryptosporidium (Scottish Water) There are a number of species of Directions 2003, all Scottish Water’s Cryptosporidium, and not all are thought treatment works should have at least 12 to be infectious to humans. All species final water samples taken and tested for form bodies known as oocysts in which Cryptosporidium during the year. The they can survive in the environment for exact sample frequency is determined by long periods. Once ingested, the risk assessment process defined in the Cryptosporidium multiplies rapidly in the Cryptosporidium Directions. gut and oocysts are excreted in very large In 2007, Scottish Water again improved numbers, completing the life-cycle of the sampling compliance with the specified organism. In humans, infection can cause sampling frequencies, with 11,393 final stomach cramps and diarrhoea and, in water samples being taken; although the extreme cases, can be fatal to the total number of works at which samples immuno-compromised or to the very were collected was slightly lower (Table young or old. 3.2-d). Of these samples, 927 contained Cryptosporidium oocysts can enter a Cryptosporidium oocysts, meaning 8.1% water supply if faecal material is washed of final water samples were positive, a into the source (raw) water and if any significant increase on 2006. oocysts present are not removed by the Interestingly, the number of works treatment process. Standard chlorine recording a positive result fell in 2007, disinfection is not generally effective suggesting that a smaller group of works against oocysts, so removal using a filter were recording a larger number of barrier is the best option. The detections. Just under half of all Scottish Cryptosporidium (Scottish Water) Water’s treatment works recorded at least Directions 2003 set out the measures one positive sample during 2007. The Scottish Water is expected to take to increase in the number of positive monitor and operate assets to prevent samples for Cryptosporidium in the 2007

15 Drinking Water Quality in Scotland 2007 Scotland data is not entirely surprising as during works and in the catchment are possible. the year there were a number of high DWQR has urged Scottish Water to fully profile boil notices issued following investigate and utilise all available positive detections. These included measures in order ensure that supplies Blairnamarrow, Langholm, North are protected. DWQR will be monitoring Ronaldsay, Torrin and Ullapool. Further this situation closely. details on these boil notices may be found The maximum oocyst count in treated within the incident section of the regional water in 2007 was 16.21 oocysts per 10 pages (Section 4) of this report. litres at North Ronaldsay in Orkney. It is possible that the high summer rainfall Fourteen out of 49 samples taken at this experienced in 2007 is to blame for the works contained oocysts, with an average increase. What is clear, is that a number oocyst count of 0.45 per 10 litres. The of Scottish Water’s treatment works do site with the highest proportion of positive not constitute an adequate barrier to samples was Waterstein on Skye, with prevent Cryptosporidium entering the 83% of samples containing oocysts. This water supply. Following the Summer site is due to be de-commissioned and the incidents, DWQR requested that Scottish area supplied from Glendale by the end of Water take appropriate measures to 2008. A total of 162 sites did not record protect these supplies. Although the any positive samples in 2007, this construction of the permanent treatment represents 54% of the sites at which processes required will take time, a samples were taken. number of operational measures at the

16 Drinking Water Quality in Scotland 2007 Scotland

3.3 Drinking Water Quality in Distribution Systems

The network of water mains, service Service reservoirs and water towers are reservoirs and water towers which carries constructed at points in the distribution drinking water from the treatment works system to store water, both for hydraulic to the consumer is known as the reasons and to even out patterns of water distribution system. Regardless of how demand through the day. Service thoroughly drinking water has been reservoirs that are not maintained in good treated, the condition of the distribution structural condition can be prone to system can have a significant effect on inward leakage from contaminated surface the quality of the water passing through water. it. Cast iron mains can corrode and add Secondary disinfection is installed at some particles of iron to the water. Deposits of service reservoirs, but this should only be iron, manganese or aluminium can used where chlorine residuals diminish accumulate in the system, perhaps from because of long distribution networks. In inefficient treatment processes, long since such cases there may be a need to boost replaced. These deposits can be stirred disinfection levels to achieve a disinfection up by changes in the flow causing residual at the end of the network. It is discoloured supplies. If the integrity of important that secondary disinfection does the distribution system is breached, or re- not disguise a more fundamental problem growth of microbiological organisms with a service reservoir such as occurs, bacterial contamination can occur. compromised structural integrity. Scottish Careful management of the distribution Water adopts a risk-based approach to system is therefore required in order to cleaning and refurbishing service ensure that the quality of the treated reservoirs. The DWQR inspects a drinking water is not allowed to selection of structures each year in order deteriorate during its journey to to ensure that they are being maintained consumers. and operated in a way which minimises any risk to water quality.

17 Drinking Water Quality in Scotland 2007 Scotland

Table 3.3-a Summary of Microbiological Tests on Samples Taken from Storage Points and Comparison with Previous Years

Coliforms 2007 2006 2005 2004 2003 2002 2001 Standard = 0 per 100ml in at least 95% of samples from each site Number of tests 56,277 56,175 56,410 56,340 56,582 58,445 56,542 Number containing coliforms 127 123 224 328 245 403 298 % containing coliforms 0.23 0.22 0.39 0.58 0.43 0.69 0.53 E.coli (Faecal coliforms) Standard = 0 per 100ml Number of tests 56,277 56,175 56,410 56,340 56,582 58,445 56,542 No. containing faecal coliforms 16 32 35 72 46 93 88 % containing faecal coliforms 0.03 0.06 0.06 0.13 0.08 0.16 0.16

The Regulations require that Scottish environmental water. A number of sites Water sample every storage point once a recorded more than one failure. Scottish week for every week it is in operation. Water investigates each failure and takes Faecal coliforms must not be present in action where required, reporting these to any sample taken from a service reservoir DWQR, Local Authorities and Health and for coliform bacteria, the requirement Boards via the event reporting system. is that 95% of samples are free of Five samples taken from Kerse service contamination. reservoir in South Ayrshire contained coliforms. As a result, this site was Summary results for storage points in audited by DWQR. Although it is likely 2007 (Table 3.3-a) compared to those for that the siting of the sample point previous years show that 0.23% of contributed to the failures, a number of samples contained coliforms. This deficiencies were also found and these are represents a slight deterioration in being rectified by Scottish Water. Four compliance on 2006 – disappointing in a sites failed to meet the regulatory year when almost every other compliance requirement that 95% of samples will not measure has improved. Of the failures, contain coliforms. 88 occurred during the months of June to September when water temperatures are E.coli (faecal coliforms) were found in 16 higher and microbiological activity is (0.03%) of samples, half the rate of the correspondingly greater. The high rainfall previous year. Eleven of these sample in the Summer may also have been a failures occurred in July and August. One factor, although it is vital that the integrity service reservoir – Holland on North of storage points is maintained and they Ronaldsay, Orkney – produced two are not liable to ingress from samples containing E.coli during the year.

18 Drinking Water Quality in Scotland 2007 Scotland

Table 3.3-b Distribution Maintenance Index (DMI) in Scotland

No. Samples No. Samples No. Samples Rank Site name Region Failed for Failed for Failed for DMI Iron Manganese Turbidity 1 Altnaharra zone North West 11066.67% 2 Penwhirn Barclye zone South East 21075.00% 3 Barclye zone South East 20083.33% 3 Cullivoe Shetland zone Islands 11083.33% 3 Elgol Skye zone North West 10083.33% 3 Kilberry zone North West 01083.33% 7 Ascog Bute zone North West 01091.67% 7 Braes Skye zone North West 10091.67% 7 Coiltie zone North West 10091.67% 7 Dhu Loch Bute zone North West 10091.67% 7 Glenlatterach zone North West 10091.67% 7 Killin zone South West 01091.67% 7 Penwhirn Palnure zone South East 10091.67% 7 Rhynie zone North East 10091.67% 7 Stronsay Orkney zone Islands 01091.67% 7 Tiree zone North West 01091.67% 7 Winterhope zone South East 01091.67% 18 Whitehillocks zone North East 50093.06% 19 Lerwick Shetland zone Islands 31094.44% 19 Loch Eck zone North West 04094.44% 19 Penwhirn zone South East 40094.44% 22 Rawburn zone South East 30095.83% 23 Roberton zone South East 20097.10% 24 Auchneel zone South East 10097.22% 24 Badentinan zone North West 11097.22% 24 Belmore zone North West 01097.22% 24 Black Esk Winterhope zone South East 01097.22% 24 Corsehouse zone South West 10097.22% 24 Kaim Lochwinnoch zone South West 10097.22% 30 Bradan B zone South West 06097.37%

Mean Distribution Maintenance Index in Scotland 99.15%

Distribution Maintenance Index, or DMI, performance of the distribution system (formerly known as OPI(TIM)) is a and its tendency to cause discoloured measure used by all the UK drinking water water incidents. quality regulators to monitor the Turbidity is a measure of the cloudiness of performance of distribution systems. DMI the water, and iron and manganese are looks at regulatory sample data for the two substances most commonly turbidity, iron and manganese at associated with discoloured supplies. consumer taps. These are the three Whilst iron in water supplies is commonly parameters that best reflect the

19 Drinking Water Quality in Scotland 2007 Scotland associated with the corrosion of cast iron a significant reduction in the number of water mains, it may also originate from a iron exceedences, as the two other poorly performing water treatment works parameters have not seen any which is failing to adequately remove improvement. This suggests that, whilst naturally occurring iron from the raw Scottish Water’s extensive water mains water. Elevated levels of manganese rehabilitation programme is showing always originate from a treatment source. benefits, more work remains to be done Both iron and manganese may be to improve treatment processes to ensure deposited in distribution systems where efficient manganese removal. low flows enable them to settle out and The table also shows the worst performing accumulate. Such deposits may later be zones in 2007, reflected by the lowest disturbed by changing flow patterns DMI scores. Many of the supply zones causing discoloured supplies. DMI is a listed are in the North West region. In measure of the extent to which these part, this can be explained by the small substances are accumulating in the populations of many of these zones which distribution system and the effectiveness means that only a small number of of the techniques used by Scottish Water samples require to be taken throughout to keep the distribution system clean. A the year. One failure within a small full description of DMI, which is derived dataset can have a large impact upon from the Mean Zonal Compliance for the DMI. This also explains why many of the three parameters, can be found in Annex DMI scores are the same. Despite this, E. there is no doubt that many of these small Table 3.3-b shows that overall DMI for supplies do allow large amounts of iron to Scotland in 2007 was 99.15, an enter the distribution system, usually due improvement on the 98.86 index for 2006. to inadequate treatment. In 2006, 62 supply zones had an DMI of The Authorised Departure process less than 100%, meaning there was at (described in Annex C) provides a formal least one failure of a test for turbidity, iron process by which Scottish Ministers can or manganese. This figure was 61 in track failing zones and require Scottish 2007, suggesting that although the Water to install appropriate remedial number of failures of these parameters measures. Cannich, the zone with the has decreased, they are spread over a lowest DMI in 2006, has improved since similar number of supply zones. These the old supply was replaced by a new may be the same zones as 2006, or borehole source and treatment works at failures that are occurring in new zones Tomich, such that it no longer appears in where water quality has deteriorated over the table. A worrying new entrant to the the year, replacing zones where an table is Whitehillocks supply zone in the improvement has been seen. The North East which had five iron failures in improvement in the overall index is due to 2007. DWQR has submitted a list of

20 Drinking Water Quality in Scotland 2007 Scotland supply zones to Scottish Water in which it manganese and the extremely poor expects full investigations to be condition of the distribution system are undertaken in order to identify sections of having a serious impact on consumers. A main requiring rehabilitation. DMI and large amount of work to rehabilitate water consumer discolouration contacts have mains is underway, and consumers should been used to produce this list to ensure be noticing a gradual improvement in that the work is targeted at areas most in quality, although the extensive nature of need of quality improvements. the work required means that it does take time to complete. The area immediately As in previous years, several supply zones around Newton Stewart should experience which feature on the table are in the same a noticeable improvement in quality later area of Dumfries and Galloway and are in 2008 when the two non-compliant supplied by the Penwhirn, Barclye and treatment works at Palnure and Barclye Palnure water treatment works or a are replaced by a supply from the existing combination of these. The failure of the Penwhirn treatment works. treatment works to remove iron and

21 Drinking Water Quality in Scotland 2007 Scotland

3.4 Drinking Water Quality at Consumer Taps

Table 3.4-a Summary of Microbiological Tests on Samples Taken at Consumer Taps with Comparison for Previous Years

Coliforms 2007 2006 2005 2004 2003 2002 2001 Standard = 0 per 100ml Number of tests 14,555 14,710 14,263 13,988 15,625 16,299 17,180 Number containing coliforms 78 114 138 123 135 204 158 Percentage containing coliforms 0.54 0.77 0.97 0.88 0.86 1.25 0.92 E.coli (Faecal coliforms) Standard = 0 per 100ml Number of tests 14,554 14,702 14,263 13,988 15,625 16,299 17,180 Number containing faecal coliforms 5 92118243023 Percentage containing faecal coliforms 0.03 0.06 0.15 0.13 0.15 0.18 0.13

Microbiological compliance at consumer zone where 6 failures were recorded. The taps improved significantly in 2007, 5 E.coli failures all occurred in different building on the improvements seen the supply zones. Scottish Water is expected previous year. Table 3.4-a shows sample to investigate all microbiological failures at data for coliform bacteria and E.coli. consumer taps and take action to protect Many of the larger water supply zones public health if the failure proves to be saw multiple coliform failures in 2007, the due to the water supplied rather than the most notable being Milngavie M2 supply tap itself.

Figure 3.4-a Year on year Comparison of the Percentage of Tests from Consumer Taps Failing the Regulatory Standard

2007 2006 2005 2004 0.08

0.07 d 0.06 0.05 0.04 0.03 0.02 % Tests Standar Failing 4 0.01 0 0 2 05 0 0.00 2 06 0 7 2 0 ) s r 0 ty s u ) m e d es 2 i m rm o H u ron s d r o l (p I e Lea an bi o if o ini an h r lif l C t u o o on ng e T C I lum m C n A o al tal e Ma l o ha ec T rog ri a d T (F y li H al co ot . T E

22 Drinking Water Quality in Scotland 2007 Scotland

Most tests to verify compliance with the not meet the standard. Although this regulations are undertaken on samples represents an improvement on previous taken from consumers’ taps. Sample years, much work clearly remains to be frequencies are determined by the done. This group of substances are by- population of the water supply zone. products of the disinfection process and Sample locations are chosen at random compliance is best achieved by installing within the zone and it is expected that treatment to remove the precursor sampling will be evenly distributed compounds that react with chlorine to throughout the year. form THMs as well as ensuring tight control of chlorine dosing systems. The ten key parameters that are of most significance for drinking water quality Iron compliance has improved markedly accounted for 90.1% of the 393 failing this year, probably in response to the samples in 2007. Figure 3.4-a shows the extensive programme of mains year on year change in percentage rehabilitation currently underway in compliance for these parameters since the Scotland. Upgraded treatment processes introduction of the 2001 Regulations at will also be partly responsible for this the start of 2004. The improvement in improvement. The benefit of this work compliance is striking, especially for should be noticed by consumers as a colour, iron and total trihalomethanes reduction in the amount of times they (THMs). This undoubtedly reflects the experience discoloured water. extensive and ongoing investment to bring Unfortunately, the manganese parameter, the numerous small rural supplies with which is also responsible for causing basic treatment up to modern standards. discoloured supplies, has not shown an Table 3.4-b summarises the results of all improvement in compliance in 2007. This samples taken from consumers taps in is disappointing, especially as there is 2007. The ten key parameters are shown extensive work nearing completion in first. A description of the significance of North Ayrshire, a former manganese these parameters may be found on a fold- “hotspot”. It is likely that the full benefits out page on the back cover of this report. of this work are yet to be felt, but also, The remaining parameters are listed and more worryingly, another location – alphabetically. The number of Authorised Loch Eck Supply Zone around Dunoon – is Departures refers to those in force for that showing a marked deterioration in parameter at any point during 2007. compliance for this parameter. Scottish Water is examining how it might include The largest number of failing samples was the necessary remedial work in its current for the THM parameter, with 80 samples investment programme. DWQR is of the not meeting the standard – overtaking opinion that such work has now become Coliform Bacteria, for which compliance urgent, and needs to proceed without has improved significantly. Of the 1,737 delay. samples analysed for THMs, 4.61% did

23 Drinking Water Quality in Scotland 2007 Scotland

Table 3.4-b Summary of all Tests on Consumer Tap Samples during 2007 # Total No. No. of Zones with % of Failed No. of Zones Mean Zonal Parameter * of Failed Authorised Samples with failures Compliance Samples Samples Departures

Key Parameters

Coliform Bacteria (Total coliforms) 14,555 78 0.54% 54 0 99.55%

E. coli (Faecal coliforms) 14,554 5 0.03% 5 0 99.95%

Colour 5,374 28 0.52% 25 12 97.97%

Turbidity 5,373 4 0.07% 4 0 99.95%

Hydrogen ion (pH) 5,374 33 0.61% 26 2 97.49%

Aluminium 5,356 16 0.30% 11 0 99.35%

Iron 5,356 50 0.93% 35 6 98.55%

Manganese 5,356 45 0.84% 32 0 98.95%

Lead 1,739 15 0.86% 13 0 99.29%

Total Trihalomethanes 1,737 80 4.61% 46 11 94.94%

Other Parameters

1,2 Dichloroethane 1,734 0 0.00% 0 0 100.00%

Aldrin 1,735 0 0.00% 0 0 100.00%

Ammonium 5,375 7 0.13% 6 0 99.73%

Antimony 1,736 0 0.00% 0 0 100.00%

Arsenic 1,736 0 0.00% 0 0 100.00%

Benzene 1,734 0 0.00% 0 0 100.00%

Benzo 3,4 Pyrene 1,740 1 0.06% 1 0 99.96%

Boron 1,739 0 0.00% 0 0 100.00%

Bromate 1,738 1 0.06% 1 0 99.72%

Cadmium 1,736 0 0.00% 0 0 100.00%

Chloride 1,738 0 0.00% 0 0 100.00%

Chromium 1,736 0 0.00% 0 0 100.00%

Clostridium perfringens 5,353 2 0.04% 2 0 99.92%

Conductivity 5,374 0 0.00% 0 0 100.00%

24 Drinking Water Quality in Scotland 2007 Scotland

No. of Zones with Total No. of % of Failed No. of Zones Mean Zonal Parameter Failed Authorised Samples Samples with failures Compliance Samples Departures

Copper 1,739 1 0.06% 1 0 99.72%

Cyanide 1,737 0 0.00% 0 0 100.00%

Dieldrin 1,740 0 0.00% 0 0 100.00%

Enterococci (Faecal streptococci) 1,739 1 0.06% 1 0 99.93%

Fluoride 1,738 0 0.00% 0 0 100.00%

Heptachlor 1,741 0 0.00% 0 0 100.00%

Heptachlor epoxide 1,735 0 0.00% 0 0 100.00%

Mercury 1,736 0 0.00% 0 0 100.00%

Nickel 1,736 0 0.00% 0 0 100.00%

Nitrate 2,531 0 0.00% 0 0 100.00%

Nitrite 2,531 14 0.55% 4 0 99.91%

Nitrite/Nitrate formula 2,531 0 0.00% 0 0 100.00%

Odour 5,372 1 0.02% 1 0 99.86%

PAH - Sum of 4 Substances 1,740 2 0.11% 2 0 99.93%

Pesticides - Total Substances 3,093 1 0.03% 1 0 99.99%

All Other Individual Pesticides 13,131 7 0.05% 2 0 99.96%

Selenium 1,736 0 0.00% 0 0 100.00%

Sodium 1,739 0 0.00% 0 0 100.00%

Sulphate 1,739 0 0.00% 0 0 100.00%

Taste 5,371 1 0.02% 1 0 99.86% Tetrachloroethene/Trichloroethene - Sum of 2 Substances 1,734 0 0.00% 0 0 100.00%

Tetrachloromethane 1,734 0 0.00% 0 0 100.00%

Total for All Parameters 160,601 393 0.24% 167 15 99.60%

*Only parameters in Schedule 1 of the Regulations (shaded) are used in the calculation of Overall Compliance

25 Drinking Water Quality in Scotland 2007 Scotland

Compliance with the standards for the this work closely. Where this work is non-key parameters has also improved. nearing completion, water supply zones Scottish Water has taken action to resolve are surveyed to establish whether or not local issues that were causing failures of they will comply with the 10µg/l standard. the standards for ammonium, bromate These surveys are to be completed by and nitrite. The failures of the nitrite February 2009, at which point a decision standard in 2006 were an issue in the will be taken as to the requirement for supply zones supplied by Marchbank WTW any future work. The only certain, and to the west of Edinburgh. Scottish Water sustainable, way of achieving full has taken action to reduce nitrification in compliance with the standard is to remove the distribution system and improve all lead pipework. This will prove a control of the chloramination process at difficult task to achieve as much of it is in the treatment works. Results are privately owned properties, however currently encouraging, although DWQR DWQR will be working with other groups will continue to watch closely. to try to find an appropriate means of progressing towards this ultimate goal. Work is underway to improve compliance with the current lead standard of 25µg/l and the revised standard of 10µg/l, which takes effect from 2013. Lead is not present in water leaving the treatment works, but may be dissolved from old lead pipes that are sometimes present in consumer plumbing and communication pipes connecting properties to the water main. Properties constructed after about 1970 do not generally contain lead, although some plumbing after this date contains solder with a high lead content; a practice that has also now been discontinued. Map 3.4 shows exceedences of the current lead standard and the future revised 10µg/l standard in Scotland during 2007. Scottish Water is making progress to install and optimise phosphate dosing at works supplying those zones identified as being at risk of exceeding the lead standard. Phosphate inhibits the tendency of the water to dissolve lead, and DWQR is monitoring

26 Drinking Water Quality in Scotland 2007 Scotland

Map 3.4 Failures of Existing (25µg/l) and Future (10µg/l) Lead Standard in 2007

27 Drinking Water Quality in Scotland 2007 Scotland

3.5 Summary of Drinking Water Quality Events and Incidents

Scottish Water must inform DWQR of any causes and impact of any incident, event at a water treatment works or in the including details of the remedial action distribution system that could adversely taken and actions by Scottish Water to affect water quality, cause concern to prevent a recurrence. Where appropriate consumers or attract media attention. DWQR will investigate further. All events Each event is assessed by the DWQR and where a boil notice or alternative supplies may be classified as an incident, if it was are issued are classified as an incident sufficiently serious or had the potential to regardless of whether a report is be serious. Usually, DWQR will request a requested by DWQR. full report from Scottish Water on the

Table 3.5-a Summary of Drinking Water Quality Incidents in 2007

Supply Zone Waterwatch Area Date Commenced Incident Type Achmelvich North West 12/01/2007 Disinfection Failure Kilmuir North West 29/01/2007 Disinfection Failure Invermoriston North West 31/01/2007 Disinfection Failure Aberdeen Old North East 01/02/2007 Vandalism Dalwhinnie North West 05/02/2007 Disinfection Failure Kenmore North East 08/02/2007 Disinfection Failure Lochinver North West 11/02/2007 Disinfection Failure Sallachy North West 14/02/2007 Disinfection Failure Blackpark North West 15/02/2007 Disinfection Failure Scourie North West 02/03/2007 Disinfection Failure Lemreway Islands 13/03/2007 Disinfection Failure Sallachy North West 17/03/2007 Disinfection Failure Glenfinnan North West 17/03/2007 Disinfection Failure Dornie North West 21/03/2007 Disinfection Failure Dalwhinnie North West 06/04/2007 Disinfection Failure Inverinate North West 10/04/2007 Disinfection Failure Shieldaig North West 23/04/2007 Disinfection Failure Acharacle North West 23/04/2007 Disinfection Failure Bradan South West 21/04/2007 Treatment (Aluminium) Failure Assynt North West 28/04/2007 Disinfection Failure Londornoch North West 02/06/2007 Treatment (Aluminium) Failure Camphill South West 05/06/2007 Manganese Failure Oykel Bridge North West 15/06/2007 Disinfection Failure Blairnamarrow North West 23/06/2007 Cryptosporidium Southdean Mill South East 26/06/2007 Cryptosporidium Inverasdale North West 14/06/2007 Treatment (Turbidity) Failure Ballachulish North West 04/07/2007 Disinfection Failure

28 Drinking Water Quality in Scotland 2007 Scotland

Supply Zone Waterwatch Area Date Commenced Incident Type Inverinate North West 06/07/2007 Cryptosporidium Carrick Castle North West 06/07/2007 Disinfection Failure Craignure North West 06/07/2007 Disinfection Failure Camphill South West 09/07/2007 Oil Contamination Elphin Knockan North West 08/07/2007 Disinfection Failure Savalbeg North West 01/07/2007 Disinfection Failure Amlaird South West 16/07/2007 Treatment (Iron) Failure Altnaharra North West 17/07/2007 Disinfection Failure Langholm South East 22/06/2007 Cryptosporidium Torrin North West 30/07/2007 Cryptosporidium North Ronaldsay Islands 09/08/2007 Cryptosporidium Windyfield Rhynie North East 07/08/2007 Cryptosporidium Lintrathen Zone North East 04/08/2007 Mains Repair - Low chlorine Langholm South East 17/08/2007 Cryptosporidium Blairnamarrow North West 21/08/2007 Cryptosporidium Invermoriston North West 11/09/2007 Telemetry Failure Gorthleck North West 22/07/2007 Disinfection Failure Tullich North West 06/09/2007 Organisms in Supply Elsrickle South West 06/09/2007 Disinfection Failure Tobermory North West 26/09/2007 Treatment (Aluminium) Failure Touch South West 07/10/2007 Telemetry Fail Badcaul North West 27/10/2007 Delay in Alarm Call Out Torridon North West 27/10/2007 Disinfection Failure Ardrishaig North West 31/10/2007 Process Failure Sheil Bridge North West 01/11/2007 Telemetry Failure Badcaul North West 08/11/2007 Disinfection Failure Turriff North East 09/11/2007 Treatment (pH) Failure Picketlaw New South West 12/11/2007 Treatment (Aluminium) Failure Torrin North West 13/11/2007 Disinfection Failure Bonar Bridge North West 14/11/2007 Disinfection Failure Lumsden North East 16/11/2007 Disinfection Failure Lochenkit South East 23/11/2007 Treatment (Aluminium) Failure Dores North West 10/12/2007 Distribution Operation Issues Carron Valley South West / South East 08/12/2007 Treatment (Aluminium) Failure Staffin North West 18/12/2007 Disinfection Failure Glenfarg North East 14/12/2007 Distribution Operation Issues Windyfield Rhynie North East 17/12/2007 Disinfection / Telemetry Failure

29 Drinking Water Quality in Scotland 2007 Scotland

Figure 3.5-a Summary of 2007 Drinking Water Quality Incidents by Type and Waterwatch Scotland Area

Treatment Failure Disinfection Failure 70 Cryptosporidium Distribution System Issue Telemetry or Alarm Response Other

60

50

40

30 No. of Incidents No. of 20

10

0 South West North West North East South East Islands All Scotland

In 2007, 1,407 event notifications were events where a water quality alarm received from Scottish Water. Of these, resulted in prompt action by operational 64 were classified as incidents by DWQR. staff, thus preventing an event becoming a more serious incident. This is Table 3.5-a and Figure 3.5-a summarise encouraging, but more work is needed to the drinking water quality incidents that ensure that this type of response becomes occurred during 2007. Despite the the norm and the number of incidents ongoing improvements to the treatment reduces. processes and water quality alarm systems at the many small water Failures of the treatment process in the treatment works in the North West region, South West area in 2007, often involved this area still generates the majority of the coagulation process where pH control incidents. Many of the incidents involved was not as robust as it should have been. failures of the disinfection process where The number of incidents reported from chlorine dosing failed for various reasons. the Island region reduced significantly in However, DWQR has noted that there was 2007. an increase in 2007 in the number of

30 Drinking Water Quality in Scotland 2007 Scotland

A notable feature of 2007 was the number However, temporary solutions remain in of incidents involving the detection place at Blairnamarrow and Langholm of Cryptosporidium in treated water. because progress with the permanent Several communities, including Tomintoul solution has taken longer than hoped. (Blairnamarrow) in Moray, and Langholm While DWQR appreciates the complexities in Dumfries and Galloway had multiple of the capital investment framework boil water notices imposed by the local within which Scottish Water operates, NHS Board in order to protect public public health must not be put at risk. health. The presence of Cryptosporidium DWQR is therefore considering taking in the water supply was partly due to the enforcement action to ensure that a extremely wet weather last summer, but degree of urgency is applied to the also because the treatment process at the improvements. DWQR expects a more works serving these communities was not proactive approach from Scottish Water in sufficiently robust to deal with the risk identifying risk posed by inadequacies in presented by the incoming raw water. its water treatment processes to ensure NHS Boards, politicians and local people that, as far as possible, improvements can have all expressed their concern over the be planned and public health protected. issue. The situation is clearly unacceptable, and DWQR has worked with Scottish Water to ensure that improved treatment is put in place at these sites.

31 Drinking Water Quality in Scotland 2007 Scotland

3.6 Summary of Contacts about Drinking Water Quality

Scottish Water is required to record details malfunctioning pumps and throttled of any complaints or enquiries it receives consumer stop taps. If air is the cause of from consumers concerning drinking the milky water, the cloudy appearance water quality. These contacts may be will clear in a glass of water from the received by telephone, letter or email. bottom up.

Table 3.6-a and Figure 3.6-a show the Stained Washing number and type of telephone contacts recorded by Scottish Water in 2007. The Brown or black staining of clothes can meaning of the categories used by occur on clothes inadvertently washed in Scottish Water is described below: discoloured water. If clothes are kept damp, the staining can often be removed Appearance of the Water by gently acidifying with a suitable substance such as citric acid. However, Discoloured Water staining may also arise from a fault with Water with a discernable taint or colour the washing machine. caused by suspended or dissolved matter. Particles in water Two of the most common causes are a yellow taint caused by dissolved organic Visible particulate matter in water which is matter arising from peat in upland sources otherwise not discoloured. This can be and more general orange, brown or black caused by corrosion of iron mains or discolouration caused by suspended deposits of sand, grit or other material particles of iron (orange/brown) and present in the main being re-suspended manganese (black). Iron discolouration following a change in the flow in the main. may occur through natural iron present in the raw water passing through inadequate Organisms in water treatment or from corrosion of cast iron Complaints of insects or other animals in distribution mains. Manganese is present the water supply. Most complaints arise in some raw waters and may not be where an insect has crawled up a tap or is removed if treatment is inadequate. present in the sink. Very occasionally water systems can contain animals which Aerated (Milky or Cloudy) Water may arise from the raw water, treatment Water which has a milky appearance works or within the mains themselves. caused by tiny bubbles of entrained air This is extremely rare, however organisms which dissolve in the water under such as midge larvae (Chironomid) or pressure but come out of solution at the water shrimp (Aesellus) have occasionally consumer’s tap. A number of causes are been found in domestic supplies. possible including burst mains,

32 Drinking Water Quality in Scotland 2007 Scotland

Taste or Smell of the Water Metallic

Metallic tastes may arise from an excess Chlorine or Phenolic of iron, aluminium or other metal Excess residual chlorine or the reaction of dissolved in the water, although normally chlorine with phenolic compounds which there will also be visible discolouration. may be present in household plumbing Occasionally phenolic complaints may be can result in taste and smells. Chlorine described as metallic. taste and smells should dissipate if the water is left to stand in the fridge for a Musty or Earthy few hours. It will also not be present Musty or Earthy tastes can arise due to after boiling. Phenolic tastes can be more naturally occurring compounds present in persistent. Common descriptions used by raw waters that have not been removed customers include TCP, medicinal, by the treatment process. Geosmin is one swimming pool, bitter, and chemical. such compound commonly associated with Common sources of phenol include earthy/musty tastes. Complaints are washing machine hoses, tap washers and more common in the summer months kettles. British Standard approved when biological activity is highest – algal plumbing products which do not contain blooms in raw water sources are common phenol should be used in all plumbing causes of widespread musty tastes. installations.

Figure 3.6-a Categories of Water Quality Contact (Complaint and Enquiry) Received by Scottish Water in 2007

Discoloured Water 70%

Aerated (Milky) Water 11%

Stained Washing 0% Organisms in Other Contact Water 6% 1% Chlorine or Particles Illness Concerns Musty or Earthy Metallic Phenolic in Water 0% 2% 2% 5% 3%

33 Drinking Water Quality in Scotland 2007 Scotland

Table 3.6-a Drinking Water Quality Contacts Received by Scottish Water During 2007 – Comparison with 2006

Contact Category Number % Change Contact rate per on 2006 10,000 population

Appearance 2007 2006 2007 2006

Discoloured Water 18,661 20,778 -10.2% 37.4 41.6 Aerated (Milky) Water 2,885 3,694 -21.9% 5.8 7.4 Stained Washing 70 73 -4.1% 0.1 0.1 Organisms in Water 228 92 147.8% 0.5 0.2 Particles in Water 694 432 60.6% 1.4 0.9 Taste and Odour

Chlorine or Phenolic 1,421 3,285 -56.7% 2.8 6.6 Metallic 409 560 -27.0% 0.8 1.1 Musty or Earthy 491 891 -44.9% 1.0 1.8 Other Contact About Water Quality* Other Contact 1,843 2,025 -9.0% 3.7 4.1 TOTAL CONTACTS ABOUT WATER 26,702 31,830 -16% 53.5 63.8 QUALITY

The pie chart and table show the number of the report. A category relating to and type of contacts received by Scottish consumer requests for information has Water about drinking water quality in been excluded from the figures as it was 2007. The figures are a sum of what evident that this contained a significant Scottish Water classifies as complaints and proportion of contacts unrelated to enquiries. Having audited Scottish quality. Water’s consumer contact handling In 2007, Scottish Water report that they process with respect to drinking water received 26,702 consumer contacts, quality in early 2008, DWQR considers it representing a reduction of 16% on 2006. unhelpful to make the distinction between As in previous years, by far the largest these types of contact, and consequently category of contacts received (70%) has added the two classifications together. related to the discolouration of water In last year’s report Drinking Water supplies. As the benefits of Scottish Quality in Scotland 2006, only those Water’s programme of rehabilitation of contacts Scottish Water classified as cast iron mains begins to realised, DWQR complaints were considered in this section expects the number of discolouration

34 Drinking Water Quality in Scotland 2007 Scotland contacts received to fall sharply in future Supply Zone in North Ayrshire reporting a years. Areas that experienced large significant number of contacts about milky numbers of contacts in 2006 such as water. In Castlehill, this may have been North Ayrshire and Newton Stewart in the rehabilitation work that was underway Dumfries and Galloway were again during 2007, enabling air to enter the prominent in the 2007 data. Work is well mains. If so, 2008 should see an under way in both of these areas to improvement. improve the quality of supplies, and Contacts to Scottish Water about tastes DWQR expects to be able to report a and odours have reduced significantly in significant reduction in the number of 2007. The largest decrease was for discolouration contacts from both of these chlorine or phenolic tastes and odours, areas in 2008. where contacts have more than halved. During the course of 2007, a few other Many of the contacts in this category in areas have experienced significant 2006 were from the two Marchbank numbers of discolouration contacts. Loch supply zones covering Western Edinburgh Eck Supply Zone in the Cowal Peninsular and parts of West Lothian. The majority around Dunoon, Loch Ascog Supply Zone of these contacts, nearly 800, were on Bute and Gartcarron Supply Zone in received in association with the incident at rural Stirlingshire all generated significant Marchbank WTW in July 2006, although it numbers of discolouration contacts and seems as though chlorine contacts in contact rates in excess of 200 per 10,000 these zones have reduced significantly population. Work is planned at Loch throughout the year, perhaps due to Ascog treatment works in order to install a Scottish Water’s efforts to control nitrite manganese removal process which should formation in the distribution system. A prevent naturally occurring manganese notable decrease in chlorine contacts was from entering supply and discolouring the also seen in Forehill supply zone, covering water. DWQR is currently pressing Peterhead. This area was highlighted by Scottish Water to take similar action at DWQR in last year’s annual report. Loch Eck treatment works. It is likely that While this apparent reduction in contacts the discolouration in Stirlingshire is due to is to be welcomed, DWQR’s perception iron sediment, and Scottish Water is from contacts received directly by the working to identify and address the Regulator and via Waterwatch Scotland is section of mains causing the issue. that the taste and smell of the water is Milky or cloudy water is an occurrence becoming more, not less, important to that can be quite alarming to consumers consumers. Two Shetland water supply although the usual cause is a simple one - zones – Lerwick and Eela Water – air dissolved in the water. In 2007, 11 % recorded a particularly high rate of of contacts were due to this, with Camps contacts about chlorine tastes. Further Supply Zone in Lanarkshire and Castlehill details may be found in Chapter 4.

35 Drinking Water Quality in Scotland 2007 Scotland

Figure 3.6-b Number of Treatment Works in Each Disinfection Index Category by Year

DI 19 or less (Good Control) 60 DI 20 - 99 DI 100 or more (Poor Control)

50

40 W 30 No. WT No. 20

10

0 2004 2005 2006 2007

It is vital that all drinking water supplies been set the target of ensuring all are adequately disinfected to ensure that treatment works have a disinfection index pathogens such as E.coli are not present. below 100 by 2010. The number of Chlorine has been used to disinfect water treatment works falling within each supplies for over 100 years and is a safe disinfection index category for each region and established technique that is used for the last three years is shown in Figure throughout the world. Some people are 3.6-b. It can be seen that the number of very sensitive to the taste of chlorine and treatment works in the poorest performing find it unpleasant. One way of minimising category (greater than 100) has the impact of chlorine on consumers, as significantly reduced over the four years well as reducing the likelihood of chemical that the index has been used. by-products forming in the water, is to ensure chlorine dosing is consistent without large fluctuations in concentration.

The DWQR uses a ”disinfection index” to assess control of chlorine at treatment works, and has set Scottish Water targets linked to the investment process to ensure improvements are made at the sites in most need of improved control. A higher disinfection index indicates less consistent dosing of chlorine. Scottish Water has

36 Drinking Water Quality in Scotland 2007 Scotland 3B Private Water Supplies in Scotland

It is acknowledged that the quality of Scottish Government and agencies such water from private supplies is highly as the Food Standards Agency, is actively variable and when poor can cause engaged in trying to further understand significant health problems. This section this complex situation and in the 2008 discusses the situation in Scotland and the annual report, DWQR will hopefully be regulatory framework that has been able to provide a more robust estimate of developed to facilitate improvements in the transient population number. the quality of drinking water from private The Private Water Supplies (Scotland) water supplies. Regulations and associated grant scheme It has been estimated that around came into force on 3 July 2006. These 150,000 people in Scotland rely on a measures were required to implement the private water supply for their drinking European Drinking Water Directive water with thousands more using them 98/83/EC and also incorporate other occasionally each year, typically when recommendations on the delivery of safe they are on holiday. Definitive numbers drinking water, including elements of the are difficult to obtain as the number of latest guidance from the World Health supplies and the use to which they are put Organisation and Scotland’s E.coli O157 constantly changes across Scotland. In Task Force Report. The strengthened the data returns requested from local Regulations build on earlier Regulations authorities, the DWQR asked for the that had been in force since 1992. The population on private water supplies in principle aim of the strengthened each local authority area and defined this regulatory framework is to ensure that all number as being “the maximum number those who use private water supplies can supplied on any one day”. This definition do so safely. allows a truer picture of the potential A private water supply is any supply which exposure to drinking water from private is not provided by the statutory water water supplies and from the returns we undertaker, which in Scotland is Scottish find that around 3.35% of the population Water. Private water supplies are is using private water supplies for drinking classified as Type A or Type B. Type A water. supplies attract mandatory monitoring and This number masks the “transient” enforcement of water quality standards by population, i.e. those who travel into an local authorities; Type B supplies are area for example on holiday, stay a few subject to a discretionary regime which, in days or weeks at most and then move on. approach, is similar to the previous A number of studies suggest that this regulatory regime. transient population is at greatest risk Local authorities are responsible for the from illness arising from private water enforcement of the strengthened supplies. DWQR, in collaboration with the

37 Drinking Water Quality in Scotland 2007 Scotland

Regulations. The duty (and cost) of Risk Assessments ensuring a private water supply meets the A core part of the revised regulatory requisite standard falls on the “relevant package is the introduction of risk person”. The local authority must identify assessments for private water supplies. the relevant person for each supply. It These risk assessments are designed to will be: highlight any real or potential risks to (a) the person providing the supply; or drinking water quality. For example, the (b) the person occupying the land risk assessment requires the source of the from, or on, which the supply is private water supply to be examined to obtained; or (c) any person who exercises powers ensure that access to animals is denied. of management or control in If animals can access the source then relation to the supply. there is potential for faecal contamination to occur resulting in human illness.

The relevant person could, therefore, be a Local authorities were required to landowner who has sold or rented complete risk assessments for all Type A properties which rely on a private supply supplies in their area as soon as that originates on his land, or a tenant if practicable but with a target date of he occupies the land on which the supply 31 December 2007 set for completion. originates. In the case of a failure to Despite assurances from local authorities comply which is due to the pipework that the vast majority of Type A supplies within a property, the owner or person would be risk assessed by the target date, responsible for the pipework in the the data returns for 2007 show that only property (the “responsible person”) is around 27% of Type A risk assessments stated to be liable for rectifying the had been completed by the due date. deficiency. While it is for individual local authorities to Relevant persons on a Type A supply may ensure that they comply with the apply for a temporary departure from the requirements of the revised Regulations, statutory requirements if they believe the DWQR is concerned about that apparent supply will fail to meet one or more of the lack of progress reported by local quality standards. A temporary departure authorities. The situation will be may only be authorised if certain monitored closely through 2008 and conditions are met. There are notification unless there is a very significant requirements to publicise any temporary improvement in the completion and departure to those who may be affected. reporting of Type A risk assessments, Temporary departures are intended to last DWQR will undertake a detailed audit of for the minimum period necessary to local authority activity in respect of Type A complete the remedial action but they can risk assessments and, if necessary, seek last for up to three years. In exceptional additional powers to ensure that local circumstances an authorised departure authorities carry out their duties in respect can be extended. of the Private Water Supplies (Scotland) Regulations 2006.

38 Drinking Water Quality in Scotland 2007 Scotland

Information Notices Small Community Supply Management Network (SCSMN), Any premises served by a private water World Health Organisation (WHO) supply, which is used as part of a commercial or public activity must display In October 2007, DWQR along with the an information notice indicating that it is Scottish Government and the Drinking served by such a supply. This Water Inspectorate for England and Wales requirement fulfils a commitment made by hosted the 4th meeting of the World the Scottish Government to implement the Health Organisation’s Small Community recommendations of the E. coli O157 Task Supply Management Network. At the Force report. meeting delegates from over 17 countries as diverse as Australia and Uganda,

Bangladesh and St Lucia, participated in Grant Scheme meetings and seminars that ran over 4 The Scottish Government has funded a days in Edinburgh. The work being done grant scheme, available through local in Scotland in trying to address the issues authorities, to assist with the one-off costs associated with drinking water quality of works to improve the nature or quality from private water supplies (also known of a private supply. This can include the as small community supplies) was show- installation of treatment equipment or the cased to the delegates and the provision of a new private supply or developments being made in Scotland domestic distribution system of up to the were acknowledged as being at the value of £800. forefront of such developments across the world. While details of the uptake of the Grant Scheme is properly a matter for the The DWQR is delighted to be associated Scottish Government to publish, DWQR with the SCSM Network and is committed notes that there has been a slow up take to continued participation of the work of of the Scheme and endorses the efforts of the Network. Further details of the both the Scottish Government and local Network can be found on the WHO authorities in trying to encourage greater website: uptake and also to undertake research (http://www.who.int/water_sanitation_he into the possible issues that are alth/dwq/scwsm_network/en/index.html ). preventing users and owners of private water supplies from accessing this resource to improve the quality of their drinking water.

39 Drinking Water Quality in Scotland 2007 Scotland

Delegates to the SCSM Network meeting, Edinburgh October 2007

More Information distribution through local authorities, which provides information designed to For more information on private water support improvements in drinking water supplies a website quality. Users and owners can also www.privatewatersupplies.gov.uk contact their local authority environmental has been built specifically to assist the health department directly (their contact owner and users of private water supplies. details will be in the local telephone A toolkit has also been developed for directory).

40 4. Drinking Water Quality by Region

41 Drinking Water Quality in Scotland 2007

4 Drinking Water Quality by Region

Introduction

This section looks at drinking water quality relevant standards. Under certain in the five Waterwatch Scotland panel circumstances, an Undertaking may be areas. For ease of reference the Orkney, sought from Scottish Water, although for Shetland and Western Isles panel area is all practical purposes this operates in referred to as the “Islands” throughout exactly the same way as an Authorised the Regional section and all the panel Departure. areas are further broken down into the Where a water quality issue is more constituent local authority areas (Map 4). urgent, or it is considered that the above This section highlights a number of approach has not delivered the required specific water quality issues, and DWQR’s improvements, DWQR can take approach to resolving these. Where one enforcement action against Scottish Water or more parameters fail to meet the requiring it to carry out the prescribed regulatory standard and are likely to action by a specified date. continue to fail, DWQR will ask Scottish Where large numbers of consumer Water to apply for an Authorised complaints are received from a certain Departure, which includes a commitment area, the DWQR will investigate and to make improvements to the supply request that Scottish Water take any concerned and to ensure that it meets the action necessary to resolve the problem.

Regional Key Facts

Table 4a Regional Key Facts

South North North South Islands Scottish Water West West East East Total Raw Water Sources 174 180 108 131 67 534 Water Treatment Works 46 148 35 50 47 307 Storage Points 283 354 366 270 53 1,088 Supply Zones 75 148 41 67 47 354 Population (000's) 2,598 458 1,303 1,659 67 4,989

* Some assets / zones serve multiple regions. Regional totals include any asset / zone wholly or partly in the region, so some are counted in more than one region. Scottish Water Total represents actual number in Scotland

42 Drinking Water Quality in Scotland 2007

Map 4: Waterwatch Scotland Panel Regions and Local Authorities

43 Drinking Water Quality in Scotland 2007 South West

4.1 Drinking Water Quality in the South West

Treatment Works

Table 4.1-a Samples Taken from Water Treatment Works Supplying the South West

No. WTW not Number % WTW not % exceeding meeting Parameter Number of tests exceeding meeting regulatory standard regulatory standard requirements requirements Coliforms 11,249 3 0.03% 3 6.52% Faecal Coliforms (E.Coli ) 11,249 0 0.00% 0 0.00% Nitrite 423 0 0.00% 0 0.00% Turbidity 4,151 27 0.65% 14 30.43%

As in 2006, E.coli was not detected in any works, contained coliform bacteria. The samples taken from water treatment proportion of treatment works with works in the South West region. Three turbidity failures was largely unchanged in samples, all from different treatment 2007(Table 4.1-a).

Table 4.1-b Summary of Disinfection Indices at Treatment Works Supplying the South West

2005 2006 2007 No. WTW Included 43 45 43 Average Index 22.7 31.5 25.3 No. Indices >100 221 The disinfection index (DI) is used by the consumers. The higher the DI, the less DWQR to track the progress being made consistent the chlorine level in water by Scottish Water in improving control of leaving the treatment works. its disinfection processes. This is to make Scottish Water has been funded to sure that all supplies are thoroughly undertake work to ensure all water disinfected to keep them safe, whilst at treatment works have a DI of less than the same time, limiting the extent to 100 by 2010. Once again, disinfection which chlorine concentrations fluctuate. indices at works in the South West have Inconsistent chlorine residuals in water not changed significantly overall in 2007 leaving treatment works are a major (Table 4.1-b), although only one site had cause of taste and odour complaints from a DI in excess of 100.

44 Drinking Water Quality in Scotland 2007 South West

Distribution System

Table 4.1-c Summary of Samples taken from Service Reservoirs in the South West

Parameter Number No. containing % exceeding No. service % service reservoirs of tests coliforms or standard reservoirs not not meeting E.coli meeting regulatory regulatory requirements* requirements Coliforms 15,062 45 0.30% 2 0.71% Faecal Coliforms (E.Coli) 15,062 3 0.02% 3 1.06% *95% samples shall not contain coliforms; 100% shall not contain E.coli

The number of samples taken from not meeting the standard of 95% of service reservoirs in the South West that samples free from coliforms were Kerse contained coliforms increased from 40 to and Maukinhill, both in Ayrshire. E. coli 45 in 2007, in contrast to an overall trend detections at service reservoirs remained of improved microbiological compliance the same as last year. (Table 4.1-c). The two service reservoirs

Table 4.1-d DMI in the South West – Supply Zones not scoring 100% Water Supply Zone Name MZC MZC MZC DMI Iron Manganese Turbidity Killin zone 100.00% 75.00% 100.00% 91.67% Corsehouse zone 91.67% 100.00% 100.00% 97.22% Kaim Lochwinnoch zone 91.67% 100.00% 100.00% 97.22% Bradan B zone 100.00% 92.11% 100.00% 97.37% Camphill zone 100.00% 97.22% 97.22% 98.15% Bradan A zone 100.00% 94.74% 100.00% 98.25% Castlehill zone 100.00% 95.83% 100.00% 98.61% Dougliehill zone 95.83% 100.00% 100.00% 98.61% Gartcarron zone 100.00% 95.83% 100.00% 98.61% Daer A zone 97.37% 98.68% 100.00% 98.68% Glendevon A zone 98.68% 97.37% 100.00% 98.68% Burncrooks zone 100.00% 97.22% 100.00% 99.07% Carron Valley B zone 97.22% 100.00% 100.00% 99.07% Daer Glassford zone 100.00% 97.22% 100.00% 99.07% Balmore G zone 97.30% 100.00% 100.00% 99.10% Balmore B zone 98.68% 98.68% 100.00% 99.12% Daer Camps zone 100.00% 98.08% 100.00% 99.36% Greenock zone 98.08% 100.00% 100.00% 99.36% Milngavie M2 zone 100.00% 98.08% 100.00% 99.36% Carron Valley A zone 100.00% 98.68% 100.00% 99.56% Muirdykes zone 100.00% 98.68% 100.00% 99.56%

South West Region Mean DMI 99.55% 99.11% 99.96% 99.54%

45 Drinking Water Quality in Scotland 2007 South West

Distribution Maintenance Index (DMI) is a measure of the performance of the distribution system for the parameters likely to cause discolouration at consumers’ taps (Turbidity, Iron and Manganese). The overall DMI for the South West region in 2007 was 99.54, a slight improvement on the 2006 figure of 99.4% (Table 4.1-d).

Although Killin is at the top of the list, the DMI is a consequence of one failing sample for manganese, highlighting a shortcoming in the statistical method used for calculating DMI for smaller zones where fewer samples are taken. Poor manganese compliance also affected four zones in Ayrshire: Castlehill, Camphill and Bradan A and B. Extensive work is underway in all these zones and DWQR expects improved compliance in the Castlehill and Camphill zones in 2008, However, visible improvement in the compliance for Bradan A and B may take a little longer to materialise.

46 Drinking Water Quality in Scotland 2007 South West

Figure 4.1-a DMI and Consumer Discolouration Contacts in the South West

47 Drinking Water Quality in Scotland 2007 South West

Consumer Contacts Scotland. Extensive work is underway in Figure 4.1-b Consumer Contacts about all of these areas to rehabilitate old water Drinking Water Quality in the South West mains. In the case of Camphill, work to install manganese removal at the South West Scottish Water Average treatment works is complete, with work on the distribution system due to be 45 40 completed in Summer 2008. 35 30 Milky or cloudy water continues to be the 25

pop. 20 second largest category of contacts for 15 10 the South West region. Camps supply 5 Contact Rate per 10,000 0 zone in Lanarkshire and Rosebery in l l l l l l r r e e e e e t t m m m a a S S S Midlothian recorded a large number of / / / W W e e e ) t t t d s s s e y a a a r k il T T u contacts about this issue during 2007, T o M e ic y l ( n ll h o i a t c d r t r s e lo e a i t although the totals in this category can E D a h M / r C e ty s A u fluctuate from year to year. M The region does not generally experience high volumes of contacts about the taste and smell of the water. Elsrickle supply zone in South Lanarkshire recorded seven Scottish Water’s South West region contacts about chlorine. As the zone has generated 14,549 contacts from a population of only 101, this gave the consumers about water quality, giving a highest chlorine contact rate in Scottish rate of 57.1 per 10,000 population, which Water. Disinfection at Elsrickle is is slightly higher than the average for achieved using ultra-violet light (UV), so Scotland as a whole. Finlas water supply no chlorine is used under normal zone on the Argyll / Dunbartonshire circumstances, however an incident in border generated the largest complaint September caused the UV disinfection rate, with nearly one fifth of the 1,141 system to fail temporarily and it may be people in the zone having contacted that Scottish Water used temporary Scottish Water about their water quality. chlorine dosing or brought in chlorinated Almost all of these contacts were supplies from another area until it was concerning discoloured supplies. restored. In terms of absolute numbers of Muirdykes supply zone in Renfrewshire discolouration contacts (Figure 4.1-b), recorded 16 metallic taste contacts. Camphill and Bradan A and B zones in Although a relatively small number, this is Ayrshire, and Carron Valley A zone in an unusual category, and the zone central Scotland had some of the highest featured for this reason in DWQR’s numbers of contacts in the whole of analysis of 2006 data.

48 Drinking Water Quality in Scotland 2007 South West

Incidents In 2007, there were seven water quality under way in order to prevent this type of incidents in the South West Region, a incident, which has affected the area for a decrease of two on the previous year. number of years.

Camphill, N.Ayrshire 09 July 2007

Bradan, Ayrshire 21 April 2007 Treatment Failure Treatment Failure On Wednesday 4th July 2007, a quantity of mineral oil was mistakenly put into This incident occurred due to a failure of hydraulically operated equipment used to one of the two air compressors providing drive the valves on the rapid gravity filters air to drive the Dissolved Air Flotation at Camphill WTW. Following a burst clarifiers due to a lack of lubrication. The which occurred on the high pressure side other compressor had failed just over two of the hydraulic power pack it was weeks previously, also due to lubrication discovered that the oil used was not of problems, and had been deemed food grade type. A persistent small oil uneconomical to repair. The compressors leak meant there was the potential for a were 15 years old. The failure of the very small quantity of mineral oil to have second compressor resulted in the filters seeped into the clarified water. Sampling being overloaded and elevated and checks revealed that in fact no oil concentrations of aluminium in the water entered the water. DWQR viewed this entering supply. Aluminium incident very seriously and has requested concentrations in the distribution system ongoing Scotland wide checks by Scottish breached the prescribed concentration or Water on oil types. value (PCV) at several locations in the hours following the incident. Amlaird, 16 July 2007

Camphill, N.Ayrshire 05 June 2007 Treatment Failure Discoloured Supplies A ferric sulphate dosing pump failed at the works, but an alarm was not generated A local discolouration of water supplies immediately since the pump continued to was caused by the unauthorised operation run. Turbidity alarms were generated of a valve by a contractor working for about an hour after the initial failure and Scottish Water. This disturbed this was followed by a high iron alarm manganese sediment in the area, which about half an hour after that. Once the discoloured the water. Approximately 230 operator arrived on site, a number of consumer calls were taken by Scottish different actions were taken to find the Water in response to this incident. cause of the problem and fix it. The Scottish Water followed established works was shut down, and water stored in protocols to clean the distribution system the two clear water tanks was used to by flushing and deliver alternative maintain supply. Iron concentrations in supplies. Extensive mains rehabilitation is

49 Drinking Water Quality in Scotland 2007 South West excess of the PCV were recorded at a few problem was discovered when an operator points in the distribution system but the attended to deal with a different alarm. action of shutting the works Although no water quality failures were down probably reduced the number of recorded following this incident, it is noted failures and the number of customer that the sampling that took place may not complaints. DWQR noted that the site have been truly representative of water staff initially failed to realise the impact of directly supplied by Touch Water the failure of the dosing system, acting Treatment Works. In response to the reactively rather than stepping back to incident, Scottish Water has implemented consider the impact on the works as a a number of actions. These include whole and water quality generally. It was improvements to chlorine stock control at also noted that changing over the ferric the site and inclusion of the chlorination dosing pumps is a scheduled monthly task pipework on the maintenance schedule. but that this task had not been carried out Elsrickle, S.Lanarkshire for at least two months prior to the 06 September 2007 incident. A number of actions by Scottish Water were agreed to prevent a UV Disinfection Failure recurrence. A failure of a mains circuit breaker led to a short interruption to the disinfection Touch, Stirling 07 October 2007 process at this site which is achieved by Disinfection Failure ultra-violet light. On the advice of the The warning system at Touch Water Consultant in Public Health Medicine, a Treatment Works that indicates which boil notice was issued for two days until bank of chlorine cylinders is operational clear sample results were obtained. had reset itself following a power failure. Scottish Water investigated the cause of Failure to spot this resulted in both banks the failure and the provision of alternative of cylinders running empty, although means of power generation to the site. chlorine stock records should have made it obvious to site operators that the second bank of cylinders was not full. A low level chlorine alarm alerted operators to the situation and following resolution of the problem the operators left the site once chlorine residuals were increasing, but crucially, before they were sufficient to reset the original low chlorine alarm. Consequently, when a subsequent blockage of the chlorination pipework occurred, no further alarm was raised. Scottish Water was fortunate that this

50 Drinking Water Quality in Scotland 2007 South West Clackmannanshire

Water Quality in Local Authorities in the South West

Clackmannanshire Council

Water Supply Zones in Area

Glendevon A Turret A Turret C

Quality of Public Water Supply

Parameter Total Total % of Number Mean Zonal number number fails of Zones Compliance of tests of fails with failures Coliform Bacteria (Total coliforms) 420 1 0.24% 1 99.74% E. coli (Faecal coliforms) 420 0 0.00% 0 100.00% Colour 128 0 0.00% 0 100.00% Turbidity 128 0 0.00% 0 100.00% Hydrogen ion (pH) 128 0 0.00% 0 100.00% Aluminium 128 2 1.56% 1 98.68% Iron 128 1 0.78% 1 99.34% Manganese 128 2 1.56% 1 98.68% Lead 16 0 0.00% 0 100.00% Total Trihalomethanes 16 0 0.00% 0 100.00% Other Parameters 2,261 0 0.00% 0 100.00% All Parameters 3,901 6 0.15% 2 99.92%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 29 48,900 447 0.91% 6 23 19

51 Drinking Water Quality in Scotland 2007 South West East Ayrshire

Water Quality in Local Authorities in the South West

East Ayrshire Council

Water Supply Zones in Area Afton Amlaird Bradan A Bradan B Corsehouse Daer A Glassford Neilston

Quality of Public Water Supply

Parameter Total Total % of Number Mean Zonal number number fails of Zones Compliance of tests of fails with failures Coliform Bacteria (Total coliforms) 1,058 3 0.28% 3 99.65% E. coli (Faecal coliforms) 1,058 1 0.09% 1 99.95% Colour 385 0 0.00% 0 100.00% Turbidity 385 1 0.26% 1 99.69% Hydrogen ion (pH) 385 2 0.52% 2 99.54% Aluminium 386 1 0.26% 1 99.85% Iron 386 3 0.78% 2 98.78% Manganese 386 12 3.11% 4 98.08% Lead 74 0 0.00% 0 100.00% Total Trihalomethanes 72 3 4.17% 2 95.83% Other Parameters 7,096 0 0.00% 0 100.00% All Parameters 11,671 26 0.22% 8 99.81%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 14 119,290 Not Supplied Not Supplied 3 11 0

52 Drinking Water Quality in Scotland 2007 South West East Dunbartonshire

Water Quality in Local Authorities in the South West

East Dunbartonshire Council

Water Supply Zones in Area Balmore A Balmore C5 North Balmore C5 South Balmore D Balmore G Burncrooks Carron Valley B Gartcarron Milngavie C1 Milngavie C4 Milngavie M1 Milngavie M4C Milngavie M5 Drumchapel M5 Craigendhill

Quality of Public Water Supply

Parameter Total Total % of Number Mean Zonal number number fails of Zones Compliance of tests of fails with failures Coliform Bacteria (Total coliforms) 1,584 10 0.63% 7 99.37% E. coli (Faecal coliforms) 1,584 1 0.06% 1 99.96% Colour 573 0 0.00% 0 100.00% Turbidity 573 0 0.00% 0 100.00% Hydrogen ion (pH) 573 1 0.17% 1 99.80% Aluminium 573 0 0.00% 0 100.00% Iron 573 2 0.35% 2 99.61% Manganese 573 2 0.35% 2 99.50% Lead 112 2 1.79% 1 98.21% Total Trihalomethanes 112 5 4.46% 3 95.54% Other Parameters 10,740 0 0.00% 0 100.00% All Parameters 17,570 23 0.13% 10 99.82%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 20 105,460 121 0.11% 0 20 0

53 Drinking Water Quality in Scotland 2007 South West East Renfrewshire

Water Quality in Local Authorities in the South West

East Renfrewshire Council

Water Supply Zones in Area Corsehouse zone Daer B Glassford Milngavie C1 Milngavie M2 Milngavie South Moorehouse Neilston Picketlaw South Moorehouse Picketlaw South Moorehouse

Quality of Public Water Supply

Parameter Total Total % of Number Mean Zonal number number fails of Zones Compliance of tests of fails with failures Coliform Bacteria (Total coliforms) 864 11 1.27% 4 99.14% E. coli (Faecal coliforms) 863 1 0.12% 1 99.96% Colour 320 0 0.00% 0 100.00% Turbidity 320 0 0.00% 0 100.00% Hydrogen ion (pH) 320 2 0.63% 2 99.63% Aluminium 320 3 0.94% 3 98.11% Iron 320 1 0.31% 1 99.24% Manganese 320 1 0.31% 1 99.83% Lead 88 2 2.27% 1 97.73% Total Trihalomethanes 88 4 4.55% 3 95.45% Other Parameters 6,728 0 0.00% 0 100.00% All Parameters 10,551 25 0.24% 10 99.76%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 11 89,290 1,252 1.40% 11 0 11

54 Drinking Water Quality in Scotland 2007 South West Glasgow

Water Quality in Local Authorities in the South West

Glasgow City Council

Water Supply Zones in Area Balmore A Balmore B Balmore C5 North Balmore C5 South Balmore D Burncrooks Daer B Daer Glassford M5 Craigendhill (ClydeSouth) Milngavie C1 Milngavie C2 Milngavie C3 Milngavie C4 Milngavie M1 Milngavie M2 Milngavie M3 Milngavie M4a Milngavie M4c Milngavie M5 Drumchapel Milngavie M5 Renfrew Muirdykes Picketlaw South Moorehouse

Quality of Public Water Supply

Parameter Total Total % of Number Mean Zonal number number fails of Zones Compliance of tests of fails with failures Coliform Bacteria (Total coliforms) 2,976 22 0.74% 12 99.20% E. coli (Faecal coliforms) 2,975 2 0.07% 2 99.95% Colour 1,040 0 0.00% 0 100.00% Turbidity 1,040 0 0.00% 0 100.00% Hydrogen ion (pH) 1,040 2 0.19% 2 99.82% Aluminium 1,040 1 0.10% 1 99.82% Iron 1,040 1 0.10% 1 99.94% Manganese 1,040 5 0.48% 5 99.56% Lead 184 4 2.17% 3 97.83% Total Trihalomethanes 184 8 4.35% 5 95.65% Other Parameters 19,062 2 0.01% 2 99.97% All Parameters 31,621 47 0.15% 17 99.79%

Summary of Private Water Supplies Glasgow City have no private water supplies

55 Drinking Water Quality in Scotland 2007 South West Inverclyde

Water Quality in Local Authorities in the South West

Inverclyde Council

Water Supply Zones in Area Blairlinnans South Dougliehill Greenock Kaim Lochwinnoch

Quality of Public Water Supply

Parameter Total Total % of Number Mean Zonal number number fails of Zones Compliance of tests of fails with failures Coliform Bacteria (Total coliforms) 396 1 0.25% 1 99.85% E. coli (Faecal coliforms) 396 0 0.00% 0 100.00% Colour 140 1 0.71% 1 99.52% Turbidity 140 0 0.00% 0 100.00% Hydrogen ion (pH) 140 0 0.00% 0 100.00% Aluminium 140 0 0.00% 0 100.00% Iron 140 3 2.14% 3 96.39% Manganese 140 0 0.00% 0 100.00% Lead 32 0 0.00% 0 100.00% Total Trihalomethanes 32 0 0.00% 0 100.00% Other Parameters 2,790 0 0.00% 0 100.00% All Parameters 4,486 5 0.11% 3 99.91%

Summary of Private Water Supplies Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 56 81,540 1,058 1.30% 9 47 14

56 Drinking Water Quality in Scotland 2007 South West North Ayrshire

Water Quality in Local Authorities in the South West

North Ayrshire Council

Water Supply Zones in Area Amlaird Castlehill Ashgrove Corrie Arran Balmichael Arran Corsehouse Bradan B Greenock Camphill Lochranza Arran

Quality of Public Water Supply

Parameter Total Total % of Number of Mean Zonal number number fails Zones with Compliance of tests of fails failures Coliform Bacteria (Total coliforms) 758 3 0.40% 3 99.79% E. coli (Faecal coliforms) 758 1 0.13% 1 99.96% Colour 286 1 0.35% 1 99.81% Turbidity 286 1 0.35% 1 99.72% Hydrogen ion (pH) 286 1 0.35% 1 99.72% Aluminium 286 1 0.35% 1 99.87% Iron 286 2 0.70% 2 98.97% Manganese 286 8 2.80% 3 98.52% Lead 70 0 0.00% 0 100.00% Total Trihalomethanes 68 3 4.41% 2 96.25% Other Parameters 5,667 0 0.00% 0 100.00% All Parameters 9,037 21 0.23% 7 99.84%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 282 135,490 238 0.18% 24 258 24

57 Drinking Water Quality in Scotland 2007 South West North Lanarkshire

Water Quality in Local Authorities in the South West

North Lanarkshire Council

Water Supply Zones in Area Balmore A Balmore F Daer A Balmore B Balmore G Daer Balmore Balmore C Pateshill Daer Camps Balmore C5 North Camps Daer Coulter Balmore C5 South Carron Valley A Daer Glassford Balmore D Carron Valley B

Quality of Public Water Supply

Parameter Total Total % of Number Mean Zonal number number fails of Zones Compliance of tests of fails with failures Coliform Bacteria (Total coliforms) 2,181 16 0.73% 10 99.19% E. coli (Faecal coliforms) 2,181 0 0.00% 0 100.00% Colour 787 0 0.00% 0 100.00% Turbidity 787 0 0.00% 0 100.00% Hydrogen ion (pH) 787 0 0.00% 0 100.00% Aluminium 791 0 0.00% 0 100.00% Iron 791 5 0.63% 4 99.45% Manganese 791 5 0.63% 5 99.49% Lead 137 2 1.46% 2 98.53% Total Trihalomethanes 137 0 0.00% 0 100.00% Other Parameters 14,264 0 0.00% 0 100.00% All Parameters 23,634 28 0.12% 13 99.93%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 15 323,780 44 0.01% 0 15 Not Supplied

58 Drinking Water Quality in Scotland 2007 South West Renfrewshire

Water Quality in Local Authorities in the South West

Renfrewshire Council

Water Supply Zones in Area Blairlinnans South Milngavie C1 Muirdykes Camphill Milngavie M3 Neilston Corsehouse Milngavie M4c Kaim Lochwinnoch Milngavie M5 Drumchapel

Quality of Public Water Supply

Parameter Total Total % of Number Mean Zonal number number fails of Zones Compliance of tests of fails with failures Coliform Bacteria (Total coliforms) 1,248 4 0.32% 3 99.76% E. coli (Faecal coliforms) 1,248 1 0.08% 1 99.95% Colour 440 0 0.00% 0 100.00% Turbidity 440 1 0.23% 1 99.75% Hydrogen ion (pH) 440 1 0.23% 1 99.75% Aluminium 440 0 0.00% 0 100.00% Iron 440 2 0.45% 2 98.48% Manganese 440 2 0.45% 2 99.63% Lead 88 2 2.27% 1 97.73% Total Trihalomethanes 88 6 6.82% 4 93.18% Other Parameters 8,343 0 0.00% 0 100.00% All Parameters 13,655 19 0.14% 7 99.74%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 104 169,590 923 0.54% 5 99 4

59 Drinking Water Quality in Scotland 2007 South West South Ayrshire

Water Quality in Local Authorities in the South West

South Ayrshire Council

Water Supply Zones in Area Afton Bradan B Bradan A Penwhapple

Quality of Public Water Supply Parameter Total Total % of Number Mean Zonal number number fails of Zones Compliance of tests of fails with failures Coliform Bacteria (Total coliforms) 588 1 0.17% 1 99.89% E. coli (Faecal coliforms) 588 1 0.17% 1 99.89% Colour 199 0 0.00% 0 100.00% Turbidity 199 0 0.00% 0 100.00% Hydrogen ion (pH) 199 2 1.01% 2 98.97% Aluminium 200 1 0.50% 1 99.67% Iron 200 0 0.00% 0 100.00% Manganese 200 10 5.00% 2 96.71% Lead 32 0 0.00% 0 100.00% Total Trihalomethanes 32 2 6.25% 1 93.75% Other Parameters 3,568 0 0.00% 0 100.00% All Parameters 6,005 17 0.28% 4 99.75%

Summary of Private Water Supplies Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 245 11,670 1,094 0.98% 30 215 16

60 Drinking Water Quality in Scotland 2007 South West South Lanarkshire

Water Quality in Local Authorities in the South West

South Lanarkshire Council

Water Supply Zones in Area Balmore B Daer A Milngavie C4 Balmore C Daer B Milngavie M2 Balmore C5 South Daer Balmore Rosebery Black Esk Daer Camps Elsrickle Camps Daer Glassford Glassford Coulter Dunside Milngavie C2

Quality of Public Water Supply

Parameter Total Total % of Number Mean Zonal number number fails of Zones Compliance of tests of fails with failures Coliform Bacteria (Total coliforms) 2,100 17 0.81% 10 99.18% E. coli (Faecal coliforms) 2,099 1 0.05% 1 99.97% Colour 736 0 0.00% 0 100.00% Turbidity 736 0 0.00% 0 100.00% Hydrogen ion (pH) 736 2 0.27% 2 99.82% Aluminium 735 0 0.00% 0 100.00% Iron 735 3 0.41% 2 99.78% Manganese 735 5 0.68% 5 99.49% Lead 136 1 0.74% 1 99.31% Total Trihalomethanes 136 3 2.21% 2 97.92% Other Parameters 13,629 2 0.01% 2 99.96% All Parameters 22,513 34 0.15% 13 99.87%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 36 307,670 252 0.08% 24 12 32

61 Drinking Water Quality in Scotland 2007 South West Stirling

Water Quality in Local Authorities in the South West

Stirling Council

Water Supply Zones in Area Ardeonaig Crianlarich Turret C Balmore D Finlas Tyndrum Balquidder Gartcarron Muirlands School Brig O’Turk Killin Strathyre Burncrooks Lochearnhead Touch Carron Valley A Turret A Carron Valley Houses Turret B

Quality of Public Water Supply

Parameter Total Total % of Number Mean Zonal number number fails of Zones Compliance of tests of fails with failures Coliform Bacteria (Total coliforms) 984 9 0.91% 6 99.23% E. coli (Faecal coliforms) 984 1 0.10% 1 99.56% Colour 346 0 0.00% 0 100.00% Turbidity 346 0 0.00% 0 100.00% Hydrogen ion (pH) 346 0 0.00% 0 100.00% Aluminium 346 1 0.29% 1 98.68% Iron 346 0 0.00% 0 100.00% Manganese 346 4 1.16% 4 98.25% Lead 99 0 0.00% 0 100.00% Total Trihalomethanes 99 0 0.00% 0 100.00% Other Parameters 7,498 1 0.01% 1 99.85% All Parameters 11,740 16 0.14% 10 99.79%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 467 87,810 3,990 4.54% 68 399 111

62 Drinking Water Quality in Scotland 2007 South West West Dunbartonshire

Water Quality in Local Authorities in the South West

West Dunbartonshire Council

Water Supply Zones in Area Alexandria Gartcarron Blairlinnans North M5 Craigendhill (Clyde South) Blairlinnans South Milngavie M4c Burncrooks Milngavie M5 Drumchapel Finlas Milngavie M5 Renfrew

Quality of Public Water Supply

Parameter Total Total % of Number Mean Zonal number number fails of Zones Compliance of tests of fails with failures Coliform Bacteria (Total coliforms) 972 4 0.41% 3 99.76% E. coli (Faecal coliforms) 972 1 0.10% 1 99.94% Colour 340 0 0.00% 0 100.00% Turbidity 340 0 0.00% 0 100.00% Hydrogen ion (pH) 340 0 0.00% 0 100.00% Aluminium 340 1 0.29% 1 97.50% Iron 340 0 0.00% 0 100.00% Manganese 340 2 0.59% 2 99.31% Lead 76 0 0.00% 0 100.00% Total Trihalomethanes 76 3 3.95% 2 96.25% Other Parameters 6,733 0 0.00% 0 100.00% All Parameters 10,869 11 0.10% 5 99.84%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 18 91,240 104 0.11% 6 12 6

63 Drinking Water Quality in Scotland 2007 North West

4.2 Drinking Water Quality in the North West

Treatment Works

Table 4.2-a Samples Taken from Water Treatment Works Supplying the North West

No. WTW not Number % WTW not % exceeding meeting Parameter Number of tests exceeding meeting regulatory standard regulatory standard requirements requirements Coliforms 9,890 8 0.08% 8 5.41% Faecal Coliforms (E.Coli ) 9,890 7 0.07% 7 4.73% Nitrite 1,134 2 0.18% 1 0.68% Turbidity 1,622 21 1.29% 12 8.11%

Microbiological compliance in the North and E.coli compliance is showing a similar West improved dramatically in 2007, marked improvement. Turbidity failures probably reflecting the extensive work at treatment works halved in 2007, that is currently underway to modernise although two nitrite exceedences occurred treatment facilities. Coliforms were at Backies WTW, whereas no failures were detected in only eight samples in 2007 recorded in the North West in the previous (Table 4.2-a), compared with 28 in 2006, year.

Table 4.2-b Summary of Disinfection Indices at Treatment Works in the North West 2005 2006 2007 No. WTW Included 133 128 113 Average Index 65.2 55.4 46.6 No. Indices >100 66 29 19

The disinfection index (DI) is used by the leaving the treatment works. Scottish DWQR to track the progress being made Water is funded to undertake work to by Scottish Water in improving control of ensure all water treatment works have a its disinfection processes. This is to make DI of less than 100 by 2010. Disinfection sure that all supplies are thoroughly indices have continued to improve disinfected to keep them safe, whilst at significantly in 2007 in the North West the same time, limiting the extent to (Table 4.2-b), with good progress made to which chlorine concentrations fluctuate. achieving the target for 2010, which will Inconsistent chlorine residuals in water undoubtedly have contributed to the leaving treatment works are a major improvements in trihalomethane cause of taste and odour complaints from compliance seen in the region, as poor consumers. The higher the DI, the less control of chlorination favours the consistent the chlorine level in water formation of these by-products.

64 Drinking Water Quality in Scotland 2007 North West

Distribution System

Table 4.2-c Summary of Samples taken from Service Reservoirs in the North West

Parameter Number No. containing % exceeding No. service % service reservoirs of tests coliforms or standard reservoirs not not meeting E.coli meeting regulatory regulatory requirements* requirements Coliforms 17,957 25 0.14% 0 0.00% Faecal Coliforms (E.Coli) 17,957 4 0.02% 4 0.61% *95% samples shall not contain coliforms; 100% shall not contain E.coli Unlike some other regions in Scottish 4.2-c), down from 19 in 2006. No storage Water, the North West saw a significant points in the region failed to meet the improvement in microbiological required 95% coliform compliance compliance at service reservoirs. Notably, standard. only four samples contained E.coli (Table

Table 4.2-d DMI in the North West – Supply Zones not scoring 100%

Water Supply Zone Name MZC MZC MZC DMI Iron Manganese Turbidity Altnaharra zone 50.00% 50.00% 100.00% 66.67% Elgol Skye zone 50.00% 100.00% 100.00% 83.33% Kilberry zone 100.00% 50.00% 100.00% 83.33% Ascog Bute zone 100.00% 75.00% 100.00% 91.67% Braes Skye zone 75.00% 100.00% 100.00% 91.67% Coiltie zone 75.00% 100.00% 100.00% 91.67% Dhu Loch Bute zone 75.00% 100.00% 100.00% 91.67% Glenlatterach zone 75.00% 100.00% 100.00% 91.67% Tiree zone 100.00% 75.00% 100.00% 91.67% Loch Eck zone 100.00% 83.33% 100.00% 94.44% Badentinan zone 95.83% 95.83% 100.00% 97.22% Belmore zone 100.00% 91.67% 100.00% 97.22% Spynie zone 100.00% 94.44% 100.00% 98.15% Assynt zone 100.00% 100.00% 95.83% 98.61% Fort William zone 95.83% 100.00% 100.00% 98.61% Newmore zone 95.83% 100.00% 100.00% 98.61% Inverness zone 98.08% 100.00% 100.00% 99.36%

North West Region Mean DMI 98.55% 98.75% 99.97% 99.09% Table 4.2-d shows DMI for supply zones failures within a very small dataset. Of in the North West not scoring 100%. the larger zones, Loch Eck in Argyll is Many of the supply zones at the top of becoming a major concern due to this list have a low DMI due to one or two persistent failures of the manganese

65 Drinking Water Quality in Scotland 2007 North West standard. Manganese has recently Consumer Contacts become a problem in the raw water supplying the treatment works. As there Figure 4.2-a Consumer Contacts about are no processes capable of removing it at Drinking Water Quality in the North West the works, it is building up in the North West distribution system, causing noticeable Scottish Water Average discolouration of supplies as well as 50 sample failures. DWQR is putting 40 pressure on Scottish Water to commit to 30 making the necessary improvements to 20 treatment, and will take enforcement 10,000 pop. 10 action if necessary. per Rate Contact 0 l l l ll r r el e e e te m m m a S S S / W / Wat e e/ e t t d ) s st e y as a a r lk T i T T u o M e ic y ( n l h ol i al t c d r t r s e o e a i E D at hl M r C y/ e t A us M

Scottish Water’s North West region generated 3,107 contacts from consumers about water quality, giving a rate of 67.8 per 10,000 population, which is about the average for Scotland as a whole Figure 4.2-a. The majority of these complaints related to discoloured water and many of the areas where these complaints came from also feature in Table 4.2-d, which gives the DMI results. Areas with a low DMI, which also received a high number of complaints, include Assynt, Badentinan and Inverness. Figure 4.2-b relates consumer contacts to DMI in the North West.

66 Drinking Water Quality in Scotland 2007 North West

Figure 4.2-b DMI and Consumer Discolouration Complaints in the North West

67 Drinking Water Quality in Scotland 2007 North West

Incidents

In 2007, there were 42 water quality Scottish Water agreed: (i) to protect the incidents in the North West region. The cable between the flow meter and the majority of these failures (69 percent) dosing pump, (ii) to make Operational were due to failures of the disinfection Team leaders aware of the need to system. To some degree, this is a communicate incidents/events directly to reflection of the basic nature and the Public Health Team, and (iii) to review geographical remoteness of the treatment task schedules to ensure all appropriate facilities in this region as there are many water quality tests are completed. very small water treatment works Kilmuir, 29 January 2007 scattered over a large area. Most of these Disinfection Failure works provide only simple disinfection This disinfection failure incident was with no other form of treatment and caused by a corroded connection on the although many did not have power or battery which provides power for the telemetry in the past, this is often no dosing pump. Due to the lack of any longer the case. The high levels of telemetry on the site, this was only Cryptosporidium at Inverinate should no noticed during a routine visit, which longer be an issue, as that area is now normally takes place three times a week. supplied by the Kyle treatment works. DWQR is in ongoing discussions with Having discovered the problem, DWQR is Scottish Water regarding reducing the risk content with the actions taken, which of Cryptosporidium in the supplies at include informing Scottish Water’s Public Blairnamarrow and Torrin. Health Team. However, DWQR expects the Public Health Team to be informed Achmelvich, 12 January 2007 immediately there is a problem and not Disinfection Failure after one hour as was the case in this This disinfection failure was caused by the instance. DWQR is also concerned about chlorine-dosing pump failing to receive a the fact that incident samples were not signal from the flow meter after a cable taken “due to the remote location of the shorted out due to adverse weather works and the limited availability of conditions. Due to the lack of telemetry operations and sampling staff”. Samples on the site, the failure was only were taken later but it is of no surprise discovered during a routine visit. Scottish that these all passed since they were Water had already undertaken to visit this taken after the problem had been fixed. site on a daily basis (including weekends) until mains power and telemetry was As a result of this incident, Scottish Water installed and commissioned (by agreed to visit the site on a daily basis 28/03/07). until the works is upgraded, to review whether visual checking of battery terminals for evidence of corrosion needs

68 Drinking Water Quality in Scotland 2007 North West to be added to task schedule for battery Dalwhinnie, 5 February 2007 sites, install duty/standby auto- Disinfection Failure changeover system for the disinfection This disinfection failure incident was dosing pumps, investigate the feasibility of caused by an air lock in the disinfection installing mains power, telemetry and pump. Due to the lack of telemetry on chlorine monitoring at the works, and the site, this was only noticed during a ensure satisfactory arrangements are in twice-weekly routine visit. DWQR is place for adequate sampling following an content with Scottish Water’s response incident/event. following discovery of the problem but Invermoriston, 31 January 2007 would expect the Public Health Team to Disinfection Failure be informed immediately, not after 5 This disinfection failure incident was hours as was the case in this instance. caused by a breach in the signal cable There was a further delay of about 3 between the flow meter and the hours before samples were taken from the disinfection pumps. works outlet and from the distribution The works is on telemetry but the low system. These delays were a recurring chlorine alarm had been suppressed, so theme at the start of 2007 and although the failure was only discovered through a Scottish Water said it was informing sampler taking a routine sample from the operational staff of the importance to works. engage with the Public Health Team immediately, the message did not get The samples taken from the works outlet through initially. DWQR has noted a all failed bacteriologically. Had the alarm recent improvement in such matters. not been suppressed, this incident could easily have been averted. DWQR was also concerned that the reason for the delay in sampling was that Suppressed alarm reports are available on “the operator had to travel to Inverness to Scottish Water’s Telemetry reporting get bacteriological bottles”. This is system. Team Leaders are to be unacceptable and such items must be reminded of the existence of this report closer to hand in case of incidents. and to check it regularly to identify unexpected suppressed alarms. Scotland As a result of this incident, Scottish Water wide training, based on previous incidents introduced Scotland-wide “Operator and events, will include the appropriate Awareness Training”, which includes actions to be taken in the event of a appropriate actions to be taken in the disinfection failure. event of a disinfection failure. Site visits were also increased at Dalwhinnie to three DWQR expects the suppressed alarm times a week, until a more robust reports to be checked on a Scotland-wide chlorination system and telemetry is basis and not just in this region. installed.

69 Drinking Water Quality in Scotland 2007 North West

Lochinver, 11 February 2007 Sallachy, 14 February 2007

Disinfection Failure Disinfection Failure This disinfection failure incident was This disinfection failure was caused by caused by a blockage (believed to be heavy rain, which caused a deterioration crystallisation of the disinfectant) in the in the quality of the raw water which then disinfection dosing line. increased the chlorine demand at the works. Due to the lack of a robust The initial low chlorine alarm was residual chlorine dosing system, the investigated at 22:30 on 11 February by a disinfection dose would not have been Network Service Operator on standby, not increased automatically in line with the a treatment operator. This person did not demand. This therefore resulted in a loss fully investigate the problem and did not of the “normal” disinfection residual. notice that there was no flow to the chlorine monitor. It was only after Residual chlorine dosing should have been discussing the matter with the treatment installed as a result of a previous incident team leader early the next morning that in August 2006 but such a system needs a the issue was fully investigated at 09:30 reliable and consistent power source, so on 12 February. the preferred option was to main out this site from Kyle water treatment works. Scottish Water’s Public Health Team were Sallachy was subsequently connected to only informed via email at 13:18 on 12 the Kyle water treatment works later in February. This is far too late in the 2007. proceedings. The Public Health Team should be informed immediately a Blackpark, 15 February 2007 problem such as this is discovered and Disinfection Failure this should be by telephone in the first This disinfection failure was caused by an instance. airlock in the disinfection dosing pumps Scotland wide ‘Operator Event Awareness due to modifications carried out the day Training’ was introduced by Scottish before the incident. Water. This training, based upon previous A low chlorine alarm was initiated on the incidents and events, includes appropriate telemetry system but there was a one and actions to be taken in the event of a low a half hour delay between the control chlorine alarm. room picking this up and relaying it to the local operator. This was partly to “prevent unnecessary call out” and also because the duty controller “would have assumed that the site would have treated water storage available”.

70 Drinking Water Quality in Scotland 2007 North West

There was a one and three quarter hour and pump fail alarms are to be manually delay between the operator arriving on generated to check that the telemetry the site and a sample of the final water system picks them up. being taken for analysis. Whilst not excessive, any such delay of this type Sallachy, 17 March 2007 should be reduced to an absolute Disinfection Failure minimum. Taking of samples should be This incident was caused by a partial one of the first actions carried out in blockage of the intake resulting in a incidents of this nature. reduction of the raw water flow which in As a result of this incident, electrical and turn caused the disinfection dosing pump mechanical personnel were to undergo to stop. Scotland-wide “Operator Event Awareness The site is on telemetry and a low chlorine Training” to make them more aware of alarm was sent from the works to Scottish the possible consequences of their Water’s central control room where the actions. Instructions were also given to staff there say they passed the alarm on the control centre that all chlorine alarms to the appropriate local person. However, have to be dispatched within 15 minutes the local staff contest that they never whenever possible. received an alarm.

Scourie, 2 March 2007 The disinfection failure therefore Disinfection Failure continued for over two days until the next This incident was caused by a failure of scheduled visit by the operator. Once on the disinfection dosing pump. The pump site, the operator dealt with the failure failure should have been picked up by the efficiently and the problem was fixed telemetry system but it would appear that within 2 hours. However, the operator the telemetry cable may have been should have informed Scottish Water’s damaged when the pump was replaced Public Health Team and should have taken due to an earlier failure of the pump on or arranged for water samples to be taken 17 February 2007. The DWQR immediately for analysis instead of waiting assessment of this earlier event was that until he had fixed the problem. It is prompt action was taken and that it did therefore of no surprise that the samples not therefore warrant an incident report. that were taken, passed. Actions are being taken by Scottish Water centrally to Scottish Water’s Public Heath Team was address issues such as these more widely promptly informed in this incident to aid within the business and Scottish Water appropriate decisions to be taken in should reap the benefits of these actions relation to sampling and the protection of in time. public health. This was the third such disinfection failure Operators are to check telemetry at this works in as many months so DWQR connections when pumps are replaced issued a draft Enforcement Notice to

71 Drinking Water Quality in Scotland 2007 North West

Scottish Water to address the matter by alarm (telling staff that the accelerating its proposal to supply communications signal from the plant had Sallachy from the Kyle works by 1 June been lost) was not passed to the 2007. This work was completed before appropriate operational staff upon receipt the end of May 2007. at the control centre. Given the reliance by Scottish Water on such battery back-up Glenfinnan, 17 March 2007 systems in these remote locations it is Disinfection Failure disappointing to note that only following This incident was caused by the failure of this incident is a weekly battery check test the chlorine-dosing pump to start in to be included in the schedule of work conjunction with the plant start up. There required to be undertaken by operators. was no information to determine the This is not the first time a battery system reason for the pump fails but inadequate has failed with the resulting loss of and incorrect prioritisation of telemetry disinfection and it would have been alarms associated with the dosed chlorine reasonable to assume that Scottish Water system resulted in no action being taken. would have taken appropriate steps to The incident was exacerbated by issues prevent a recurrence. The incorporation, surrounding the telemetry systems both in albeit belatedly, of the risk based terms of the correct response to alarms maintenance scheduled task for battery and the correct prioritising of the alarms condition checks at sites where battery themselves. The failure of Scottish Water powered dosing systems are in place staff to comply with policies and along with the inclusion of weekly battery procedures put in place to protect public tests on the scheduled tasks for operators health is a cause for serious concern and is welcomed by DWQR. the continuing training and development Dalwhinnie, 6 April 2007 of operational staff is an issue that has Disinfection Failure and will continue to feature in audits of The incident was caused by air-locked Scottish Water staff undertaken by the dosing lines in the disinfection system but DWQR. it is concerning that following the first Dornie, 21 March 2007 occurrence of the problem on 6 April 2007 Disinfection Failure that Scottish Water waited until the Evaluation of the Incident Report suggests second occurrence on 16 April 2007 that had the telemetry alarm for the loss before instigating daily checks by the of battery power been correctly assigned operator on the treatment plant. Given as a Priority 2 alarm then the incident may that the works at the time of the two have been avoided. However, a further incidents did not have telemetry, the level opportunity to prevent the event of risk posed by a failure of the escalating to an incident was lost when disinfection system was substantially the Priority 2 communications failure higher than for a works where an

72 Drinking Water Quality in Scotland 2007 North West appropriate telemetry system was raw water. The site was only visited twice installed. While DWQR welcomes the per week and this was insufficient to daily site visits by an operator until a ensure adequate disinfection at times of telemetry system is installed and poor water quality. operating it is unfortunate that such a Scottish Water is planning to introduce risk-sensitive approach was not operating additional appropriate treatment at the prior to these incidents. To prevent any plant before the end of March 2009. future occurrence of this type of treatment failure, DWQR required Scottish Acharacle, 23 April 2007 Water to review the frequency of operator Disinfection Failure checks on all treatment works where there This incident was the result of a catalogue is no installed and/or operating telemetry of errors but basically it was caused by a systems and report on the outcome of failure of one of the disinfection pumps. A that review. Scottish Water subsequently low chlorine alarm was initiated at around agreed to visit all water treatment works midday on Sunday 22 April 2007, but this that did not have telemetry at least three was not acknowledged due to the times a week. operator having suppressed the alarm the previous day. However, the plant shut Inverinate, 10 April 2007 down automatically as it was designed to Disinfection Failure because of low chlorine later that day. A This incident was caused by bad weather low level clear water tank alarm later on resulting in poor raw water quality. The resulted in a visit to the site at which time poor raw water quality increased the the plant was switched to manual chlorine demand, but since the system operation. Further low chlorine alarms can only be adjusted manually, it had to were initiated but were not acted on wait for a routine visit from the operator properly due to the suppression of the to carry out these adjustments. Scottish alarm. This suppression was removed Water subsequently agreed to visit the early the following day (Monday 23 April) site daily until the works was abandoned and another low chlorine alarm followed and the area supplied by the Kyle works on from this. The site was visited, the which eventually took place et the end of disinfection pumps switched over and the 2007. two clear water tanks dosed with Shieldaig, 23 April 2007 additional chlorine but this latter operation Disinfection Failure was not carried out in accordance with This disinfection failure was caused by procedures. There were further low heavy rain resulting in poor raw water chlorine alarms during the course of quality. Since the chlorine is only dosed Monday 23 April and the plant continued proportionate to the volume of flow to be run on manual until 10:00 on through the works it had to be adjusted Thursday 3 May. manually to cater for varying qualities of

73 Drinking Water Quality in Scotland 2007 North West

Actions included a review of the operation end to end testing, ensuring that of the works, a review of the telemetry operators fully understand the procedures system (including all alarms), checking the to follow in the event of a breach of plant to ensure it was fit for purpose (it Emergency Action Levels, adding the was still under warranty at the time), automatic coagulation unit to telemetry, communicating the severity of this adding treated and final water chlorine incident to all operational staff and alarms to telemetry and ensuring that all stressing the importance of complying operators receive training in event and with procedures, providing additional incident awareness. training for staff and placing the operator Londornoch, 2 June 2007 concerned on a formal performance Coagulation Failure review which will be monitored monthly. This aluminium failure was essentially The procedure for alarm suppression was caused by the operator adjusting the pH also to be reviewed. control to deal with an increase in Assynt, 28 April 2007 turbidity without first discussing the issue Disinfection Failure with the local process scientist. The This disinfection failure incident was situation was exacerbated by the changes caused by the operator not filling the having been made towards the end of the ammonium sulphate vat, which is an working day and the operator leaving the essential chemical in the chloramination works without waiting to check the effects process. A low chlorine dose alarm was of the changes he had made. received by the Operations Management Furthermore, it appears that high priority Centre but the operator was not called out alarms were suppressed since the to investigate. It would appear that the operator claimed not to have received any final water chlorine alarm at Assynt water alarm calls later that night or early the treatment works was not on the telemetry next morning. Even when the operator system. did acknowledge the aluminium alarm, there was a delay before he arrived on In addition to the above, the sample line site. to the automatic coagulation unit had been switched off. This resulted in too Operators should have been instructed not high a dose of polymer being added which to make changes to the process without affected the coagulation process resulting discussing these first with the process in highly coloured water which had a high scientist and Scottish Water should chlorine demand. It would appear that investigate delays in response to alarms. there are no alarms on the automatic Operators must understand the coagulation unit which would have given importance of reacting to alarms. Scottish an early warning of a problem with it. Water’s due diligence can be brought into question if there is any failure on their Actions included a full review of the part in this area. telemetry including alarms, priorities and

74 Drinking Water Quality in Scotland 2007 North West

Inverasdale, 14 June 2007 alarm alerted Scottish Water’s Operational High Turbidity Management Centre, it wrongly assumed The elevation in turbidity experienced that the operator was still on site so did during this incident was due to the draw not contact him again to investigate this down of the system by tanker operations second power fail. A further low chlorine in the area. The loss of the on-line alarm later in the day was generated and turbidity meter occurred 4 days prior to passed to the operator, but no action the tanker operations (on 8 June) but the appears to have been taken. Another low tanker log shows that no problems were chlorine alarm very early the next morning highlighted at the water treatment works was passed to the operator who took no or the clear water tank associated with action assuming that it was another faulty the works. The length of time taken to reading as there had been a few in the deal with the inoperative turbidity meter is weeks leading up to the incident. A a cause for concern. Scottish Water noted further low chlorine alarm about an hour that there were 41 High Priority jobs and later was passed out to the operator who 13 Urgent jobs in the area at the time of could not recall receiving it. Since the site the incident. Scottish Water should put is only visited twice a week, all of this measures in place to monitor Urgent and went without investigation until the next High Priority job requests along with the routine visit on the Friday 15 June 2007. provision of appropriate resources to Undisinfected water was therefore going ensure that inappropriate delays or into supply for almost 4 days. backlogs do not occur. Furthermore it was not until the situation had been resolved by mid afternoon on Oykel Bridge, 15 June 2007 the Friday that Scottish Water’s Public Disinfection Failure Health Team was informed and This was caused by a power failure on appropriate samples taken. By this time, Monday 11 June 2007 which caused the the works was running properly again and circuit breaker for the inlet flow meter to all the samples subsequently passed. trip. When the power came back on the However, even the process of taking the flow restarted but the trip for the inlet samples was not without fault as it was flow meter had not been re-set, so the delayed due to sample bottles not being disinfection pump did not detect any flow available, with the operator having to go so did not start to pump. Thus to another site to pick some up. undisinfected water was going into supply. Scottish Water interviewed staff about the The operator had been out earlier in the alarm handling errors, reconfigured the day to investigate an earlier power fail telemetry to prevent treated water and had carried out various tasks to chlorine alarms occurring when the works restore the works. However, a second is shut down, looked at the feasibility of power fail occurred after the operator had reconfiguring the works to automatically left the site and although a low chlorine

75 Drinking Water Quality in Scotland 2007 North West shut down in the event of a disinfection were taken as the chlorine residual at the system failure or flow meter/signal failure outlet of the clear water tank was always and investigated the extent of the within target levels and did not breach problem with power fails. any Emergency Action Level. However, there is no evidence to support this view. Blairnamarrow, 23 June 2007 Since no samples were taken it is not High levels of Cryptosporidium possible to say if public health was Due to high levels of Cryptosporidium compromised or not. being found in this supply, advice was issued to customers to boil their water Scottish Water held an incident report before consumption. The incident was workshop to clarify roles, responsibilities associated with heavy rainfall and and procedures between functions and to followed a number or previous incidents of give formal clear written communication a similar nature. to all staff about the handling of alarms, especially those relating to disinfection Savalbeg, 1 July 2007 failures.

Disinfection Failure Ballachulish, 4 July 2007 This incident was caused by crystallisation Disinfection Failure of the chlorine in the suction line to the This disinfection failure was caused by the chlorine pump. A low chlorine alarm was inlet valve on pressure filter no. 1 failing generated at 21:30 but this was not to close during a backwash. The passed on to Scottish Water’s alarm backwash was set to operate when the monitoring centre until midnight (00:00), clear water tank was full and the works some two and half hours later due to a was shut down. Since the valve did not fault with the remote telemetry unit at the close and the works was in shut down works. The alarm monitoring centre mode, raw water was able to pass acknowledged the alarm at 00:09, but did through the whole process without any not pass this on to the local operator until disinfection. A low chlorine alarm was 01:42 which caused another delay of an initiated but the operator took no action hour and a half. There was thus a total since he considered the 24 hours storage delay in response to the alarm of about 4 capacity and the chlorine residual levels hours. The operator arrived on site about adequate. an hour after the alarm had been Another low-level chlorine alarm was dispatched to him, which is not passed out about an hour later but the unreasonable given the time of day and operator did not recall receiving it. This the travel time to the works. Once at the was at 06:00 on Wednesday 4 July 2007. works, the operator took appropriate A decision was finally made to investigate remedial action to resolve the problem but at 10.00 and when the operator arrived at failed to inform his team leader and the the works at 13:00 he found the inlet Public Health Team. No formal samples valve to the filter open and undisinfected

76 Drinking Water Quality in Scotland 2007 North West water going into the clear water tank. DWQR continues to be concerned about The valve was closed manually and the Scottish Water’s ability to react to alarms. plant reset to backwash daily. The faulty Inverinate, 6 July 2007 valve was reported to the mechanical and High levels of Cryptosporidium electrical team, disinfection was increased High levels of Cryptosporidium resulted in to protect public health and the public advice being issued to customers to boil health team were contacted. When the their water before consumption. This valve was investigated the following day, works was closed and the area supplied nothing was found wrong with it. form the Kyle water treatment works The valve failed again (twice) on 21 July. before the end of 2007. Low chlorine alarms followed but no Carrick Castle, 6 July 2007 action was taken since it was assumed that the plant was shut down. Disinfection Failure Investigation and remedial work took This incident occurred when a fault with place on 23 and 24 July. However, the the electronics controlling the works valve failed again on 30 July and again meant that un-disinfected water passed low chlorine alarms were not acted on but into supply until the problem was work was carried out later in the day. discovered during a routine site visit approximately nine hours later. The It took a further week to finally establish a investigation in response to this incident problem with a configuration of the discovered that the alarm from the treated closing signal for the valve which was water chlorine monitor that should have then changed and checked to ensure it alerted operational staff to the problem was operating effectively. had, in fact, been inhibited three years Scottish Water agreed to investigate the earlier due to a fault. Despite several communication failures between the duty work orders having been raised to repair and standby operators, to investigate the the monitor, they were never actioned. feasibility of alarming the valve status and Scottish Water was unable to say why this including another alarm to detect flow was, and accepts that several through the filter when the works is shut opportunities to rectify the fault were down. missed.

DWQR noted the ongoing work being All chlorine analysers and alarms at the carried out by Scottish Water to improve site are now fully operational. Scottish the robustness of its telemetry system Water has committed to reviewing risk generally and their ability to react to based and reactive maintenance and alarms and to fix problems before they producing regular reports on all pose a risk to public health. Although the suppressed alarms across the company to systems appear to be getting better, enable them to be investigated. Operational staff in the area were

77 Drinking Water Quality in Scotland 2007 North West reminded of the importance of ensuring noticed. An air lock in the dosing pump that alarms and monitors are operating was found and rectified. Fortunately, the correctly. problem only occurred earlier that morning so there was still a healthy Craignure, 6 July 2007 residual chlorine level. A new membrane Disinfection Failure plant is being planned for this works. Disinfection of the plant failed when a high chlorine alarm switched off the Gorthleck, 22 July 2007 dosing pumps midway through a Disinfection Failure duty/standby changeover of the This disinfection failure was caused by a disinfectant container vessels. The failure failure to fill up the disinfectant tank when lasted longer that it should without it was almost empty. This task should investigation because the alarm was not have been done by the operator on 19 passed on to operations from the alarm July but he was called away for personal handling centre. Scottish Water agreed to reasons and it would appear that no other carry out an investigation and take action member of staff was asked to carry out to reduce the risk of a repeat incident of his duties in his absence. A low chlorine this nature. alarm on 21 July apparently subsequently cleared itself and so was not investigated. Elphin Knockan, 8 July 2007 A further low chlorine alarm later the Disinfection Failure same day on 21 July was not passed to This incident was primarily caused by the the operator as he had confirmed that he blockage of the chlorine sample line by was already due to attend the site to organic matter derived from the source investigate a low raw water flow alarm. which had a cascade effect of shutting Having not been told about the low down the dosing system and hence chlorine alarm and with chlorine residuals triggering a low chlorine alarm condition. being adequate, the operator did not think DWQR is aware of the emerging issues to check the disinfectant levels. It was with respect to Cryptosporidium and is in therefore not until the early evening on discussion with Scottish Water and the 22 July, when the operator was Water Industry Commission for Scotland investigating a further low raw water flow regarding the installation of appropriate alarm, that he noticed the low level of treatment at this and other similar sites. disinfectant. Appropriate remedial action Altnaharra, 17 July 2007 was then taken. It was fortunate that the Disinfection Failure chlorine residual never fell below the low There is telemetry on this site but at the Emergency Action Level. time of the incident it only monitored flow Scottish Water agreed to link an and battery status. It was therefore only appropriate low level alarm for the through a routine visit to the works that a disinfectant to telemetry and investigate problem with the disinfection system was

78 Drinking Water Quality in Scotland 2007 North West the feasibility of an auto shut down facility presence in the water supply caused for a low treated water chlorine residual. significant concern to consumers.

Torrin, 30 July 2007 The Drinking Water Quality Regulator for High levels of Cryptosporidium Scotland investigated the incident, High levels of Cryptosporidium resulted in working closely with Argyll and Bute advice being issued to customers to boil Council’s Environmental Health team and their water before consuming it. DWQR is NHS Highland. concerned about the adequacy of the Whilst it was not possible to confirm the treatment process to deal with exact source of the larvae, it was likely Cryptosporidium at this works so is that they entered Tullich Water Treatment promoting an improvement project Works in the raw water coming from the through the investment planning process. lochs that supply Oban’s drinking water. Blairnamarrow, 21 August 2007 The filtration process was not able to remove all the larvae and some ultimately High levels of Cryptosporidium broke through into supply. Once the Due to high levels of Cryptosporidium problem was detected, increased washing being found in this supply, advice was of the filters quickly improved the issued to customers to boil their water situation. Scottish Water’s own report before consuming it. Due to this and the into the incident highlighted a number of event earlier in the year on 23 June 2007, operational changes that were be made to DWQR investigated Scottish Water’s ensure no recurrence of the incident. actions to reduce the risk of a recurrence. DWQR also made recommendations, some Some work was carried out in the in connection with the operation of the catchment, at the inlet works and on the treatment works and some concerning the filters at the works in an attempt to way in which Scottish Water responds to improve the situation. In the longer term consumer concerns and keeps people DWQR is working with Scottish Water to informed. Although this was an unusual introduce more robust treatment at this occurrence, DWQR expects Scottish Water works. to take all possible steps to ensure there Tullich, 6 September 2007 is no repetition. Organisms in the filters Invermoriston, 11 September 2007 In September 2007, Scottish Water’s Telemetry Failure customers in the Oban area complained The DWQR assessment of this “no water” about “worm-like organisms” in their incident is that it was probably caused by drinking water. These were later a failure of an air valve on the raw water identified as a species of Chironomid inlet main. It would appear that water midge larvae. The Soroba area of Oban came out through the air valve rather was worst affected. Whilst these larvae than going forward to the water treatment presented no risk to public health, their works. This loss of water meant that

79 Drinking Water Quality in Scotland 2007 North West there was no water going to the chlorine problems were investigated and remedial monitors, which resulted in the plant work was carried out on the pumps. believing that there was no chlorine so it Torridon, 27 October 2007 shut down the raw water pumps as it was Disinfection Failure designed to do, to prevent undisinfected The disinfection dosing pumps failed but water from going into supply. Water was the telemetry system worked and the however still being supplied from the clear problem was rectified. The chlorine water tank and when it reached its low control system was also adjusted so that level, an alarm should have been the pumps now switch on when the inlet transmitted to Scottish Water’s pumps are activated. Operational Management Centre. However, no such alarm was generated Badcaul, 27 October 2007 and consequently, customers were out of Disinfection Failure water for longer than they would have This disinfection failure incident was been had the telemetry alarm worked. In caused by a fault in the power supply to fact it was a customer calling in to say the disinfection pumps. Mains power at that they had no water which raised the the site only charges two 12 volt batteries alarm and prompted an investigation. that operate in series to provide the 24 Scottish Water’s ongoing work on its volts required to power the pumps. The telemetry system and associated alarms site is visited twice a week and the should ensure that they are all appropriate power/charging system for the pumps is and working as intended. Testing of the checked once a week. signals at Invermoriston from the works to When the first failure occurred on 27 the alarm monitoring centre had still to be October, a low chlorine alarm was carried out at the time of this incident. initiated, the operator was called out and Scottish Water were also to inspect and found the pumps were off but the power service the air valve, add a check on the system appeared to be operating chlorine sample pumps to the day to day effectively. Samples were taken which tasks for the site and review the works subsequently failed as they contained control to see if anything more could be coliforms. done to provide an earlier indication of a The system failed again very early on 28 raw water system failure. October but this time the low chlorine Tobermory, 26 September 2007 alarm failed to initiate and only came Coagulation Failure through two hours later. The operator followed a similar procedure as the earlier Problems with the aluminium dosing incident. Again the samples failed. pumps caused high levels of residual aluminium to enter the supply. However, Following an urgent request issued on 29 the telemetry system worked, the October to check for an electrical fault on the system, electrical and mechanical staff

80 Drinking Water Quality in Scotland 2007 North West went to the site on 30 October to find that works to resolve the problem, however by one battery had burst and only 5 volts their own admission it is possible that was being produced by the other. The more could have been done to mitigate standby set of batteries was found to be the effects of high aluminium fully charged so the system was set to concentrations on consumers by utilising operate on these. water stored on the site and by carrying out flushing in the distribution system. Scottish Water agreed to carry out a full Scottish Water identified this as a learning end to end check on the telemetry system point from the incident, along with the to determine the reason for the failure of timely notification of such events to the alarm on 28 October. Scottish Water’s Public Health Team who Scottish Water also agreed to install four are able to offer advice on water quality new batteries for the disinfection pumps and protecting consumers. and carry out a weekly check on the condition of all 4 batteries, together with Shiel Bridge, 1 November 2007 the charging system to ensure that it is Telemetry Failure operating at the correct voltage for A faulty electrical relay caused a power sufficient but not excessive charge. failure to the disinfection pumps. A low chlorine alarm was acknowledged by the Ardrishaig, 31 October 2007 alarm monitoring centre but it appears Treatment Failure that they did not pass this on to It is likely that Scottish Water supplied operations for them to investigate it. The water that exceeded the standard for problem was therefore only discovered aluminium to the area served by through a routine visit by the operator. Ardrishaig works, which includes This works was subsequently abandoned Lochgilphead. It is not possible to be and the area supplied from the Kyle water certain of the levels of aluminium in the treatment works around mid December distribution system because Scottish 2007. Water failed to take adequate samples to establish the impact on water quality, a Badcaul, 8 November 2007 shortcoming they identified in their report Disinfection Failure into the incident. Mains power is used for the lights and for charging the batteries which power the The cause of the failure was a malfunction disinfection pumps. The mains power in the pH correction dosing pump that failed and the batteries failed to hold their elevates the pH of the incoming water to charge so there was no power for the enable it to be treated using aluminium disinfection pumps. However, the sulphate. In response to the failure, an telemetry system worked and power was appropriate alarm was generated and an restored within 3 hours of losing it. operator attended site. Scottish Water took appropriate action at the treatment

81 Drinking Water Quality in Scotland 2007 North West

produced to allow a new Access Certificate Torrin, 13 November 2007 to be issued. Disinfection Failure Staffin, 18 December 2007 This is one of a handful of sites that still do not have telemetry so it was only Disinfection Failure though a routine visit to the works that it This disinfection failure was caused by a was found that the disinfection system split in the dosing line. However the had failed. The failure had been caused telemetry system worked and alerted by a failure of the electronic signal operations to the low chlorine which was between the flow meter and the chlorine promptly investigated and disinfection was pump. Having discovered the problem it restored. was fixed and disinfection was restored.

Bonar Bridge, 14 November 2007 Disinfection Failure Both chlorine dosing pumps tripped causing a low chlorine alarm to be initiated. However, the telemetry system worked and dosing was restored within an hour.

Dores, 10 December 2007 Failure to comply with procedures in DOMS (Distribution Operation and Maintenance Strategy) A new water main was being constructed between the treatment works at Inverness and Dores. This was to supply the area previously fed from Dores by the works at Inverness and subsequently close the works at Dores. Although double check valves were used to protect the existing live water main from any possible contamination by back flow, there was inadequate protection against the possibility of fuel for the temporary pumps getting into the excavation. Also, the contractors’ Access Transfer Certificate had expired which resulted in the contractor having to leave the site until suitable method statements had been

82 Drinking Water Quality in Scotland 2007 North West Argyll and Bute

Water Quality in Local Authorities in the North West

Argyll and Bute Council

Water Supply Zones in Area Alexandria Campbeltown Dhu Loch Bute Port Charlotte Islay Ardfern Carradale Finlas Saddell Ardrishaig Carrick Castle Gigha Tarbert Argyll Aringour Coll Claddich Inverary Taynuilt Ascog Bute Colonsay Kilberry Tighnabruaich Ballygrant Islay Craighouse Jura Kilmelford Tiree Belmore Craignure Mull Loch Eck Tobermory Mull Blairlinnans North Dalmally Lochgoilhead Torra Islay Bunessan Dervaig Mull Peninver Tullich Tyndrum

Quality of Public Water Supply Parameter Total Total % of Number of Mean Zonal number number fails Zones with Compliance of tests of fails failures Coliform Bacteria (Total coliforms) 632 3 0.47% 3 99.32% E. coli (Faecal coliforms) 632 1 0.16% 1 99.77% Colour 254 0 0.00% 0 100.00% Turbidity 254 0 0.00% 0 100.00% Hydrogen ion (pH) 254 1 0.39% 1 99.32% Aluminium 254 1 0.39% 1 99.32% Iron 254 1 0.39% 1 99.32% Manganese 254 8 3.15% 5 96.62% Lead 161 0 0.00% 0 100.00% Total Trihalomethanes 161 11 6.83% 5 93.92% Other Parameters 8,063 0 0.00% 0 100.00% All Parameters 11,173 26 0.23% 16 99.72%

Summary of Private Water Supplies Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 1,575 91,390 58,961 64.52% 344 1,083 180 148 supplies unclassified at December 2007

83 Drinking Water Quality in Scotland 2007 North West Highland

Water Quality in Local Authorities in the North West

Highland Council

Water Supply Zones in Area Achaphubuil Bracadale Skye Garve Kylesku Sconser Skye Acharacle Braes Skye Glenachulish Laggan Bridge Scourie Achnasheen Broadford Skye Glencoe Laid Shiel Bridge Achiltibuie Cannich Glenconvinth Laide Shieldaig Achmelvich Carbost Skye Glendale Skye Letterfearn Spynie Achmore Clunas Glenelg Lochaline Staffin Skye Alligin Coiltie Glenfinnan Lochcarron Stoer Altnaharra Cromarty Glenuig Lochinver Stoer Forest Skye Applecross Dalchreichart Gorthleck Mallaig Stromallus Skye Ardgour Dalwhinnie Hoy Calder Mellon Udrigle Strontian Arnisdale Diabeg Inchlaggan Melness Tarskavaig Skye Assynt Dores Inverasdale Nam Bat Teangue Skye Aultbea Dornie Invergarry New Onich Tomatin Backies Dornoch Inverinate Newmore Tomich Badcaul Drimnin Invermoriston Osedale Skye Torridon Badachro Drumbeg Inverness Oykel Bridge Torrin Skye Ballachulish Drumfearn Skye Kilchoan Penifiler Skye Trislaig Balmacara Durness Kilmaluag Skye Rassay Skye Ullapool Balnain Earlish Skye Kilmuir Skye Ratagan Waternish Beasdale Elgol Skye Kinlochbervie Rosemarkie Waterstein Skye Blackpark Elphin Knockan Kinlochewe Salen Bliach Fort Augustus Kinlochleven Sallachy Bohuntin Fort William Kishorn Savalbeg Bonar Bridge Gairloch Kyle of Lochalsh Sanna

84 Drinking Water Quality in Scotland 2007 North West Highland

Quality of Public Water Supply

Parameter Total Total % of Number of Mean Zonal number number fails Zones with Compliance of tests of fails failures Coliform Bacteria (Total coliforms) 1,384 8 0.58% 6 99.70% E. coli (Faecal coliforms) 1,384 1 0.07% 1 99.92% Colour 530 17 3.21% 15 94.19% Turbidity 529 1 0.19% 1 99.96% Hydrogen ion (pH) 530 15 2.83% 11 94.15% Aluminium 530 0 0.00% 0 100.00% Iron 530 7 1.32% 7 98.46% Manganese 530 3 0.57% 2 99.47% Lead 337 1 0.30% 1 99.76% Total Trihalomethanes 337 30 8.90% 20 91.35% Other Parameters 17,515 5 0.03% 4 99.96% All Parameters 24,136 88 0.36% 45 99.46%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 1,748 215,310 27,770 12.90% 594 1,154 334

85 Drinking Water Quality in Scotland 2007 North West Moray

Water Quality in Local Authorities in the North West

Moray Council

Water Supply Zones in Area

Badentinan Rochomie Blairnamarrow Spynie Glenlatterach Tomnavoulin Herricks Turriff

Quality of Public Water Supply

Parameter Total Total % of Number of Mean Zonal number number fails Zones with Compliance of tests of fails failures Coliform Bacteria (Total coliforms) 528 4 0.76% 2 99.45% E. coli (Faecal coliforms) 528 0 0.00% 0 100.00% Colour 184 0 0.00% 0 100.00% Turbidity 184 0 0.00% 0 100.00% Hydrogen ion (pH) 184 0 0.00% 0 100.00% Aluminium 184 0 0.00% 0 100.00% Iron 184 3 1.63% 3 96.55% Manganese 184 3 1.63% 2 98.92% Lead 60 0 0.00% 0 100.00% Total Trihalomethanes 60 0 0.00% 0 100.00% Other Parameters 4,634 2 0.04% 2 99.91% All Parameters 6,914 12 0.17% 4 99.82%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 672 86,750 Not Supplied Not Supplied 70 602 127

86 Drinking Water Quality in Scotland 2007 North East

4.3 Drinking Water Quality in the North East

Treatment Works

Table 4.3-a Samples Taken from Water Treatment Works Supplying the North East

No. WTW not Number % WTW not % exceeding meeting Parameter Number of tests exceeding meeting regulatory standard regulatory standard requirements requirements Coliforms 6,951 5 0.07% 4 11.43% Faecal Coliforms (E.Coli ) 6,951 1 0.01% 1 2.86% Nitrite 709 1 0.14% 1 2.86% Turbidity 2,614 31 1.19% 12 34.29% Whilst the number of samples containing issue with Scottish Water. Although coliforms and E.coli has reduced investigations are continuing, Scottish dramatically in 2007, the number of Water suspects that the failures may be treatment works not meeting regulatory due to inappropriate siting of the sample requirements remains the same as in 2006 tap and will act as necessary. (Table 4.3-a). Invercannie WTW, serving The 31 failures of the ex-works turbidity Aberdeen, recorded two coliform failures standard are disappointing, as the in 2007, as well as the E.coli failure. equivalent figure for 2006 was 10. DWQR has noted that this site continues Invercannie produced seven of the to produce a disproportionate number of failures, and Clatto, which supplies microbiological failures and has raised the Dundee, was responsible for three.

Table 4.3-b Summary of Disinfection Indices at Treatment Works Supplying the North East

2005 2006 2007 No. WTW Included 31 33 25 Average Index 15.8 18.3 16.0 No. Indices >100 100

The disinfection index (DI) is used by the cause of taste and odour complaints from DWQR to track the progress being made consumers. The higher the DI, the less by Scottish Water in improving control of consistent the chlorine level in water its disinfection processes. This is to make leaving the treatment works. Scottish sure that all supplies are thoroughly Water is funded to undertake work to disinfected to keep them safe, while at the ensure all water treatment works have a same time, limiting the extent to which DI of less than 100 by 2010. Table 4.3-b chlorine concentrations fluctuate. shows the North East sites generally Inconsistent chlorine residuals in water achieve good DI scores, although DWQR leaving treatment works are a major is keen to see continued improvement.

87 Drinking Water Quality in Scotland 2007 North East

Distribution System

Table 4.3-c Summary of Samples taken from Service Reservoirs in the North East

Parameter Number No. containing % exceeding No. service % service reservoirs of tests coliforms or standard reservoirs not not meeting E.coli meeting regulatory regulatory requirements* requirements Coliforms 18,820 49 0.26% 1 0.27% Faecal Coliforms (E.Coli ) 18,820 6 0.03% 6 1.64% *95% samples shall not contain coliforms; 100% shall not contain E.coli

In 2007, coliforms were detected in 49 extremely disappointing as it represents samples taken at storage points in the an increase on the 28 failures from 2006. North East (Tabel 4.2-c). Only one The number of E. coli failures has also storage point, Forebank in Angus, failed to increased, doubling from last year’s three. meet the 95% compliance standard, These failures all occurred at different however the number of coliform failures is storage points.

Table 4.3-d DMI in the North East – Supply Zones not scoring 100%

Water Supply Zone Name MZC MZC MZC DMI Iron Manganese Turbidity Killin zone 100.00% 75.00% 100.00% 91.67% Rhynie zone 75.00% 100.00% 100.00% 91.67% Whitehillocks zone 79.17% 100.00% 100.00% 93.06% Glendevon A zone 98.68% 97.37% 100.00% 98.68% Mannofield South zone 98.08% 98.08% 100.00% 98.72% Forehill zone 97.22% 100.00% 100.00% 99.07% Mannofield West zone 100.00% 98.08% 100.00% 99.36% Clatto West zone 100.00% 100.00% 98.68% 99.56% Lintrathen zone 98.68% 100.00% 100.00% 99.56%

North East Region - Mean DMI 98.70% 99.23% 99.97% 99.30%

Table 4.3-d shows all supply zones in the small dataset of compliance samples. The North East not scoring 100% for DMI in poor compliance for iron in Whitehillocks 2007. This index is a measure of the supply zone in Angus has dragged down performance of the distribution system in the overall DMI score for the region. relation to the parameters likely to cause Rehabilitation work is ongoing, and it is discolouration of supplies. The small expected that this work should address supply zones at Killin and Rhynie scored the issue. highly due to one failure occurring in a

88 Drinking Water Quality in Scotland 2007 North East

Figure 4.3-a DMI and Consumer Discolouration Contacts in the North East

89 Drinking Water Quality in Scotland 2007 North East

Figure 4.3-b Consumer Contacts about Aberdeen and Turret C in the Perthshire Drinking Water Quality in the North East and Stirling area. Further mains rehabilitation is required in these areas. North East In the case of Mannofield, treatment Scottish Water Average improvements are also necessary in order

40 to reduce these contacts and ensure 35 compliance with the manganese standard. 30 25 Scottish Water has committed to replacing 20 15 the current temporary measures for

10,000 pop. 10 manganese removal at Mannofield with a

Contact per Rate 5 0 permanent solution by August 2009. l l l l ll r e e e e ter m m m a Figure 4.3-a relates discolouration S S S / / W / Wat e e e t t d ) s st e y contacts to DMI. as a a r lk T i T T u o M e ic y l ( n l h o i al t c d Although taste and odour seems to be less r t r s e o e i t hl Ea D a M / r C y e of an issue in the North East than for t A us M other regions, the supply zones served by Glendevon water treatment works in Fife recorded a notable number of contacts in all categories for taste and odour. Forehill The North East region continues to supply zone, covering Peterhead, was generate lower rates of consumer reported as being a “hotspot” for taste contacts about water quality than the and odour contacts in 2006. The situation other regions. Discolouration remains the in 2007 improved significantly, possibly largest category (Figure 4.3-b), and the due to operational changes made at the contact rate increased in 2007 from nearly treatment works. 25 contacts per 10,000 population to just over 30. Supply zones with notably large Glendye supply zone covering Stonehaven numbers of discolouration contacts in the recorded a notable number of milky water North East include Lintrathen and contacts, probably due to air in the Whitehillocks in Angus, Mannofield East in supply.

90 Drinking Water Quality in Scotland 2007 North East

Incidents In 2007 there were eight water quality responding to the low dose and as such incidents in the North East Region, a did not generate an alarm on the increase of three on the previous year. telemetry system. Samples were taken relatively promptly, and although not all Invercannie, Aberdeen samples were totally clear of coliforms as 01 February 2007 suggested in Scottish Water’s report, the Vandalism levels were low and not of significance for This incident involved unauthorised access public health. by vandals to three access hatches on the Scottish Water committed to undertake a old aqueduct, which runs between number of actions in response to this Invercannie and Mannofield water incident, to improve maintenance at the treatment works. There was an obvious site and ensure that the works will risk of contamination of the treated water shutdown in the event of a further supply as a result. DWQR expressed disinfection failure. concern at the four day delay between the initial notification to Scottish Water from a Lintrathen Supply Zone, Angus member of the public, and the time the 04 August 2007 incident was eventually investigated. The Mains Repair Microbiological Failure subsequent sampling programme A bacteriological failure in the distribution indicated no contamination had taken system may have been caused when a place. burst on a short length of a two-inch A number of actions were taken by diameter pipe was repaired. The repair Scottish Water as a result of this incident was carried out while the system was in order to improve reporting mechanisms pressurised so the risk of contamination and review the security provided to this during the repair should have been less asset. than if the repair had been carried out Kenmore, Perthshire with the water turned off. Following 08 February 2007 investigation by DWQR, Scottish Water Disinfection Failure was unable to provide evidence of An intermittent fault with a relay switch in compliance with procedures other than a the control panel for the disinfection statement to the effect that an interview system at Kenmore borehole resulted in took place with the relevant staff, which an intermittent problem with the Sodium confirmed that procedures had been Hypochlorite dosing pumps. The system followed. Scottish Water state that the should have been configured so that such lack of a chlorine residual in the sample a fault automatically shut down the works that failed suggests that there may be an but it did not. Furthermore, the treated issue with the condition of the main. water chlorine residual monitor was not However, two resamples taken 4 days

91 Drinking Water Quality in Scotland 2007 North East later from the same location showed Investigation by Scottish Water showed reasonable levels of chlorine residuals. that on the morning of 6 August, the DWQR concluded that there is a strong chlorine residual in water leaving the possibility that the failed sample treatment works fell away to zero due to was caused by contamination due to the an extremely sudden increase in water lack of strict adherence to the flow through the works. Scottish Water relevant procedures. There was also an consider that the likeliest route by which unacceptable delay by Scottish Water in surface water containing Cryptosporidium taking resample’s. could have suddenly infiltrated the system was through the spring collection DWQR has asked Scottish Water to review chambers following exceptionally heavy its procedures in respect of ensuring rainfall. DWQR considers that the sudden hygienic conditions during any work on loss of chlorine at the site should have the distribution system, including ensuring triggered further investigation by that there is a satisfactory chlorine operational staff. A turbidity monitor residual in the system prior to work installed in 2006 at the site, which could commencing. DWQR undertook a number have triggered an alarm, had never of audits of work in the distribution functioned correctly. system during 2007 and issued a number of procedural recommendations to Work has been undertaken to ensure the Scottish Water, which are being followed turbidity monitor is operating correctly up. and disinfection at the site has been Windyfield Rhynie, Aberdeenshire significantly improved. Additionally, a 07 August 2007 temporary filtration system is in place at Cryptosporidium the site to provide an effective barrier This incident occurred when a routine against Cryptosporidium. DWQR visited Cryptosporidium sample taken on 7 the site in January 2008 as part of the August 2007 was reported on 10 August investigations and to verify that actions as containing 0.371 oocysts per 10 litres. were complete. Samples from Rhynie WTW do not Turriff, Aberdeenshire normally contain oocysts, therefore this 08 November 2007 was an exceptional result for the site. The Coagulation Process Failure Consultant in Public Health Medicine was A failure of the power supply to Turriff concerned that the community had had no Water Treatment Works caused a previous exposure to Cryptosporidium so corruption of the computer programme they requested that Scottish Water issue that controlled the lime dosing. This advice to consumers in the area to boil resulted in a more concentrated lime their water. This boil notice was slurry being produced. Although the pH subsequently lifted on 16 August. control system at the site responded correctly, it was insufficient to prevent

92 Drinking Water Quality in Scotland 2007 North East overdosing of lime and a failure of the pH including provision of trace heating to standard. DWQR is still investigating this prevent freezing. Scottish Water has incident due to late notification by Scottish investigated the delay in passing out the Water. alarm and the lack of a water quality Glenfarg Water Supply Zone, Fife sample. 14 December 2007 Failure to Follow Water Quality Procedures A contractor carrying out preliminary work on a 5” distribution main in Kirkcaldy operated a valve and isolated the network without undertaking an impact assessment and without liaising with Scottish Water Operations. This left a number of consumers without water and Scottish Water unable to explain the situation as they had not been warned of the work. Additionally, the necessary sampling to confirm that water quality was satisfactory following the work was not undertaken in a timely manner. Scottish Water has committed to improved enforcement of its DOMS procedures.

Windyfield Rhynie, Aberdeenshire 17 December 2007 Disinfection Failure A sodium hypochlorite dosing line froze on the night of 17 December leading to loss of disinfection for a period of over three hours. Although an alarm was generated, its dispatch to Scottish Water Operations was delayed. No water quality sampling was undertaken in response to the failure due to a misunderstanding over whether a routine sample was already scheduled to be taken.

Since the incident, a new chlorine dosing system has been installed at the site,

93 Drinking Water Quality in Scotland 2007 North East Aberdeen City

Water Quality in Local Authorities in the North East

Aberdeen City Council

Water Supply Zones in Area Craigie Mannofield North Glendye Mannofield South Invercannie Mannofield West Mannofield East

Quality of Public Water Supply

Parameter Total Total % of Number of Mean Zonal number number fails Zones with Compliance of tests of fails failures Coliform Bacteria (Total coliforms) 792 6 0.76% 3 99.41% E. coli (Faecal coliforms) 792 0 0.00% 0 100.00% Colour 276 1 0.36% 1 99.40% Turbidity 276 0 0.00% 0 100.00% Hydrogen ion (pH) 276 1 0.36% 1 99.40% Aluminium 276 2 0.72% 2 99.01% Iron 276 1 0.36% 1 99.73% Manganese 276 2 0.72% 2 99.45% Lead 56 0 0.00% 0 100.00% Total Trihalomethanes 56 0 0.00% 0 100.00% Other Parameters 3,868 0 0.00% 0 100.00%

All Parameters 7,220 13 0.18% 4 99.92%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 109 206,880 279 0.13% 2 107 5

94 Drinking Water Quality in Scotland 2007 North East Aberdeenshire

Water Quality in Local Authorities in the North East

Aberdeenshire Council

Water Supply Zones in Area Aboyne Gallowhill Banff Mannofield North Ballater Glendye Mannofield South Braemar Herricks Mannofield West Craighead Invercannie Rhynie Craigie Lintrathen Turriff Crathie Lumsden Whitehillocks Forehill Mannofield East

Quality of Public Water Supply

Parameter Total Total % of Number of Mean Zonal number number fails Zones with Compliance of tests of fails failures Coliform Bacteria (Total coliforms) 1,396 7 0.50% 4 99.77% E. coli (Faecal coliforms) 1,396 0 0.00% 0 100.00% Colour 498 1 0.20% 1 99.79% Turbidity 498 0 0.00% 0 100.00% Hydrogen ion (pH) 498 2 0.40% 2 99.73% Aluminium 498 2 0.40% 2 99.65% Iron 498 9 1.81% 5 97.41% Manganese 498 2 0.40% 2 99.81% Lead 129 1 0.78% 1 98.75% Total Trihalomethanes 129 1 0.78% 1 98.75% Other Parameters 7,373 2 0.03% 2 99.98%

All Parameters 13,411 27 0.20% 10 99.85%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 7,925 236,260 32,157 13.61% 220 7,705 211

95 Drinking Water Quality in Scotland 2007 North East Angus

Water Quality in Local Authorities in the North East

Angus Council

Water Supply Zones in Area Clatto East Lintrathen Clatto West Whitehillocks

Quality of Public Water Supply

Parameter Total Total % of Number of Mean Zonal number number fails Zones with Compliance of tests of fails failures Coliform Bacteria (Total coliforms) 708 2 0.28% 2 99.75% E. coli (Faecal coliforms) 708 0 0.00% 0 100.00% Colour 252 0 0.00% 0 100.00% Turbidity 252 1 0.40% 1 99.67% Hydrogen ion (pH) 252 1 0.40% 1 99.67% Aluminium 252 0 0.00% 0 100.00% Iron 252 6 2.38% 2 94.46% Manganese 252 0 0.00% 0 100.00% Lead 32 0 0.00% 0 100.00% Total Trihalomethanes 32 0 0.00% 0 100.00% Other Parameters 4,244 0 0.00% 0 100.00%

All Parameters 7,236 10 0.14% 4 99.86%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments Not Supplied 109,320 Not Supplied Not Supplied Not Supplied Not Supplied Not Supplied

96 Drinking Water Quality in Scotland 2007 North East Dundee City

Water Quality in Local Authorities in the North East

Dundee City Council

Water Supply Zones in Area Clatto East Clatto West

Quality of Public Water Supply

Parameter Total Total % of Number of Mean Zonal number number fails Zones with Compliance of tests of fails failures Coliform Bacteria (Total coliforms) 432 1 0.23% 1 99.75% E. coli (Faecal coliforms) 432 0 0.00% 0 100.00% Colour 152 0 0.00% 0 100.00% Turbidity 152 1 0.66% 1 99.34% Hydrogen ion (pH) 152 0 0.00% 0 100.00% Aluminium 152 0 0.00% 0 100.00% Iron 152 0 0.00% 0 100.00% Manganese 152 0 0.00% 0 100.00% Lead 16 0 0.00% 0 100.00% Total Trihalomethanes 16 0 0.00% 0 100.00% Other Parameters 2,468 0 0.00% 0 100.00%

All Parameters 4,276 2 0.05% 2 99.98%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 1 142,170 24 0.02% 0 1 0

97 Drinking Water Quality in Scotland 2007 North East Fife

Water Quality in Local Authorities in the North East

Fife Council

Water Supply Zones in Area Glendevon A Glenfarg_Kwoodbh_A Newburgh Glendevon B Glenfarg_Kwoodbh_B Turret A Glendevon/Glenfarg Lomond Hills Turret C Glenfarg Lomond Hills_Bh_Mix

Quality of Public Water Supply

Parameter Total Total % of Number of Mean Zonal number number fails Zones with Compliance of tests of fails failures Coliform Bacteria (Total coliforms) 1,104 3 0.27% 3 99.77% E. coli (Faecal coliforms) 1,104 0 0.00% 0 100.00% Colour 360 0 0.00% 0 100.00% Turbidity 360 0 0.00% 0 100.00% Hydrogen ion (pH) 360 0 0.00% 0 100.00% Aluminium 360 2 0.56% 1 99.74% Iron 360 1 0.28% 1 99.87% Manganese 360 2 0.56% 1 99.74% Lead 72 0 0.00% 0 100.00% Total Trihalomethanes 72 1 1.39% 1 98.75% Other Parameters 7,115 0 0.00% 0 100.00%

All Parameters 11,627 9 0.08% 5 99.95%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 327 358,930 2,932 0.82% 35 289 66

98 Drinking Water Quality in Scotland 2007 North East Perth and Kinross

Water Quality in Local Authorities in the North East

Perth and Kinross Council

Water Supply Zones in Area Clatto West Glenfarg_KwoodBh_B Lintrathen Dunkeld Kenmore Perth Glendevon A Killiecrankie Turret A Glendevon B Killin Turret B Glenfarg Kinloch Rannoch Glenfarg_KwoodBh_A Kirkmichael

Quality of Public Water Supply

Parameter Total Total % of Number of Mean Zonal number number fails Zones with Compliance of tests of fails failures Coliform Bacteria (Total coliforms) 1,476 5 0.34% 4 99.72% E. coli (Faecal coliforms) 1,476 0 0.00% 0 100.00% Colour 520 0 0.00% 0 100.00% Turbidity 520 1 0.19% 1 99.91% Hydrogen ion (pH) 520 1 0.19% 1 99.91% Aluminium 520 2 0.38% 1 99.82% Iron 520 2 0.38% 2 99.82% Manganese 520 3 0.58% 2 98.16% Lead 104 1 0.96% 1 99.17% Total Trihalomethanes 104 0 0.00% 0 100.00% Other Parameters 9,997 0 0.00% 0 100.00%

All Parameters 16,277 15 0.09% 8 99.92%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 1,299 140,190 20,530 14.64% 226 1,073 316

99 Drinking Water Quality in Scotland 2007 South East

4.4 Drinking Water Quality in the South East

Treatment Works

Table 4.4-a Summary of Samples Taken from Water Treatment Works in the South East

No. WTW not Number % WTW not % exceeding meeting Parameter Number of tests exceeding meeting regulatory standard regulatory standard requirements requirements Coliforms 10,029 13 0.13% 9 18.00% Faecal Coliforms (E.Coli ) 10,029 1 0.01% 1 2.00% Nitrite 1,053 0 0.00% 0 0.00% Turbidity 3,395 12 0.35% 10 20.00% The number and proportion of works with pleasing to see that there were no nitrite coliform fails shows an improvement fails in 2007, which is an improvement compared with the previous year but over the three fails noted in 2006 (Table E.coli and turbidity fails were unchanged 4.4-a). in 2007 compared with 2006. It is

Table 4.4-b Summary of Disinfection Indices at Treatment Works in the South East

2005 2006 2007 No. WTW Included 48 49 44 Average Index 16.9 16.0 29.9 No. Indices >100 101

The disinfection index (DI) is used by the cause of taste and odour complaints from DWQR to track the progress being made consumers. The higher the DI, the less by Scottish Water in improving control of consistent the chlorine level in water its disinfection processes. This is to make leaving the treatment works. Scottish sure that all supplies are thoroughly Water is funded to undertake work to disinfected to keep them safe, while at the ensure all water treatment works have a same time limiting the extent to which DI of less than 100 by 2010. The South chlorine concentrations fluctuate. East sites generally achieve good DI Inconsistent chlorine residuals in water scores, although DWQR is always keen to leaving treatment works are a major see continued improvement (Table 4.4-b).

100 Drinking Water Quality in Scotland 2007 South East

Distribution System

Table 4.4-c Summary of Samples taken from Service Reservoirs in the South East

Parameter Number No. containing % exceeding No. service % service reservoirs of tests coliforms or standard reservoirs not not meeting E.coli meeting regulatory regulatory requirements* requirements Coliforms 14,234 37 0.26% 1 0.37% Faecal Coliforms (E.Coli) 14,234 1 0.01% 1 0.37% *95% samples shall not contain coliforms; 100% shall not contain E.coli

Only one service reservoir failed in 2007 failure is associated with Kingston Service for coliforms and there was an Reservoir which is supplied from Castle improvement in the number of fails for Moffat Water Treatment Works in East E.coli , which reduced from 4 in 2006 to 1 Lothian. in 2007 (Table 4.4-c). The one E.coli

Table 4.4-d DMI in the South East – Supply Zones not scoring 100%

Water Supply Zone Name MZC MZC MZC DMI Iron Manganese Turbidity Penwhirn Barclye zone 50.00% 75.00% 100.00% 75.00% Barclye zone 50.00% 100.00% 100.00% 83.33% Penwhirn Palnure zone 75.00% 100.00% 100.00% 91.67% Winterhope zone 100.00% 75.00% 100.00% 91.67% Penwhirn zone 83.33% 100.00% 100.00% 94.44% Rawburn zone 87.50% 100.00% 100.00% 95.83% Roberton zone 91.30% 100.00% 100.00% 97.10% Auchneel zone 91.67% 100.00% 100.00% 97.22% Black Esk Winterhope zone 100.00% 91.67% 100.00% 97.22% Dodburn zone 100.00% 100.00% 92.31% 97.44% Daer A zone 97.37% 98.68% 100.00% 98.68% Glendevon A zone 98.68% 97.37% 100.00% 98.68% Carron Valley B zone 97.22% 100.00% 100.00% 99.07% Balmore G zone 97.30% 100.00% 100.00% 99.10% Daer Camps zone 100.00% 98.08% 100.00% 99.36% Fairmilehead A zone 98.11% 100.00% 100.00% 99.37% Carron Valley A zone 100.00% 98.68% 100.00% 99.56%

South East Region - Mean DMI 97.28% 99.02% 99.89% 98.73%

101 Drinking Water Quality in Scotland 2007 South East

Table 4.3-d shows all supply zones in the Consumer Contacts South East not scoring 100% for DMI in 2007. DMI is a measure of the Figure 4.4-a Consumer Contacts about performance of the distribution system in Drinking Water Quality in the South East relation to the parameters likely to cause South East discolouration of supplies. Rehabilitation Scottish Water Average work is ongoing in many of the worst scoring areas in the South East, including 40 35 Penwhirn and Barclye in Dumfries and 30 Galloway. It is expected that this work 25 20 should address the issue. pop. 15 10 5

Contact Rate per 10,000 0 l ll ll l r r e e e te te m m m a a /S /S W ) W ste/S ste aste a a red ilky T u e y T lo llic T (M th d rin a r lo et a isco te D h M /E ra C e sty A u M

Scottish Water’s South East region generated 8,257 contacts from consumers about water quality, giving a rate of 47.5 per 10,000 population, which is slightly lower than the average for Scotland a whole. The majority of these contacts were related to discoloured water (Figure 4.4-a) and many of the zones where these contacts came from also feature in Table 4.4-d above, which gives the DMI results. Areas which have a low DMI and which also received a high number of complaints about discolouration include Penwhirn, Winterhope and Glendevon. Figure 4.4-b co-relates DMI and consumer discolouration contacts.

102 Drinking Water Quality in Scotland 2007 South East

Figure 4.4-b DMI and Consumer Discolouration Contacts in the South East

103 Drinking Water Quality in Scotland 2007 South East

Incidents reduce the risk of Cryptosporidium from There were five water quality incidents in getting into the supply. In the meantime, the South East region. Two of these Scottish Water has introduced a related to coagulation failures and the temporary filtration system which is other three were for high levels of helping to reduce the risk. Cryptosporidium, two of which were at the Langholm, 17 August 2007 same works. DWQR is promoting work to High levels of Cryptosporidium improve the treatment at both Langholm Adverse weather again caused increased and Southdean Mill. Therefore, Scottish levels of Cryptosporidium in the Water is developing proposals to reduce catchment. A temporary filtration plant the risk of Cryptosporidium getting into was put in place following the earlier these supplies. In the short term, Scottish incident on 22 June, but due to Water has introduced temporary filtration operational issues this was not as effective systems at both sites, which appear to be as it should have been for a period of 24 helping the situation. hours. Unfortunately, this resulted in Langholm, 22 June 2007 further advice to customers to boil their High levels of Cryptosporidium water before consuming it.

Adverse weather caused high levels of Lochenkit, 23 November 2007 Cryptosporidium to get into the water Coagulation Failure supply. Advice was given to customers to A burst on the inlet main to one of the boil their water before consuming it. The service reservoirs caused an increase in treatment at Langholm is disinfection only demand for treated water, which caused and DWQR is promoting the introduction the clear water tank at the works to drain of appropriate treatment to reduce the down. A filter backwash fault at the risk of Cryptosporidium from getting into works, together with several the supply. In the meantime, Scottish communication and IT issues amongst Water has introduced a temporary operational staff, including some missed filtration system which is helping to water quality alarms, meant that the flow reduce the risk. through the treatment works was not Southdean Mill, 26 June 2007 restored before the clear water tank High levels of Cryptosporidium drained down. As a result of the Adverse weather caused high levels of interruption in the treatment process, the Cryptosporidium to get into the water quality of the water leaving the works did supply. Advice was given to customers to not initially meet regulatory standards due boil their water before consuming it. The to elevated turbidity and aluminium levels. treatment at Southdean Mill is disinfection Scottish Water scoured the system at a only and DWQR is promoting the number of points in the distribution introduction of appropriate treatment to system in order to remove the non- compliant water as quickly as possible.

104 Drinking Water Quality in Scotland 2007 South East

Scottish Water proposed a number of restored. A discrepancy between readings actions in response to this incident, on hand-held and on-line water quality including measures to improve awareness instrumentation caused initial confusion as and communications amongst operational to the actual effect of the failure on staff involved with networks and treated water quality, although laboratory treatment. The possibility of providing a analysis of a sample taken from the clear larger service water tank at the works has water tank showed that a failure of the been considered and discounted but aluminium standard did, in fact, occur. Scottish Water has investigated ways of In response to the incident, Scottish reducing the demand for service water Water has improved the arrangement at placed on the tank. Scottish Water’s the site so that the standby lime dosing actions following the deterioration in pump will start automatically. It has also treated water quality were appropriate, committed to investigating why there was except that operational staff did not a delay in passing out the alarm and inform the Public Health Team of the investigating the reason behind the event as per procedure. This meant that discrepancy between instrumentation external stakeholders such as the NHS readings. Board and Local Authority were not informed as they should have been. Scottish Water realise that they were deficient in this respect and DWQR acknowledges that this omission was not typical of the South East region.

Carron Valley, 8 December 2007 Coagulation failure This incident was due to a malfunction of the lime pump. The site has a standby lime pump, but at the time of the incident this had to be brought on line manually. A delay in Scottish Water’s Operational Management Centre passing out the alarm resulted in an operator being called to site too late to prevent the final water quality being affected. Once on site, DWQR considers that appropriate actions were taken by Scottish Water to minimise the impact of the failure. These included shutting down the flow through the plant temporarily until water quality was

105 Drinking Water Quality in Scotland 2007 South East Dumfries and Galloway

Water Quality in Local Authorities in the South East

Dumfries and Galloway Council

Water Supply Zones in Area Afton Daer A Moffat Auchneel Glengap Palnure Barclye Kettleton Penwhirn Black Esk Killylour Penwhirn Barclye Black Esk & Ringford Langholm Penwhirn Palnure Black Esk Winterhope Larchfield Terregles Cargen Lochenkit Winterhope Carsphairn Lochinvar

Quality of Public Water Supply Parameter Total Total % of Number of Mean Zonal number number fails Zones with Compliance of tests of fails failures Coliform Bacteria (Total coliforms) 784 2 0.26% 2 99.77% E. coli (Faecal coliforms) 784 0 0.00% 0 100.00% Colour 318 2 0.63% 2 97.83% Turbidity 318 0 0.00% 0 100.00% Hydrogen ion (pH) 318 2 0.63% 2 98.79% Aluminium 319 2 0.63% 1 97.83% Iron 319 12 3.76% 6 93.36% Manganese 319 4 1.25% 4 97.41% Lead 129 3 2.33% 2 97.28% Total Trihalomethanes 128 19 14.84% 7 84.06% Other Parameters 7,810 0 0.00% 0 100.00%

All Parameters 11,546 46 0.40% 12 99.25%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments

284 (Type A only) 148,000 Not Supplied Not Supplied 284 Not Supplied 70

106 Drinking Water Quality in Scotland 2007 South East East Lothian

Water Quality in Local Authorities in the South East

East Lothian Council

Water Supply Zones in Area Alnwickhill B Hopes Castle Moffat Rosebery Fairmilehead A Rosebery Hopes

Quality of Public Water Supply

Parameter Total Total % of Number Mean Zonal number number fails of Zones Compliance of tests of fails with failures Coliform Bacteria (Total coliforms) 771 4 0.52% 2 99.59% E. coli (Faecal coliforms) 771 0 0.00% 0 100.00% Colour 257 2 0.78% 1 99.46% Turbidity 257 0 0.00% 0 100.00% Hydrogen ion (pH) 257 1 0.39% 1 99.73% Aluminium 256 0 0.00% 0 100.00% Iron 256 1 0.39% 1 99.73% Manganese 256 0 0.00% 0 100.00% Lead 52 1 1.92% 1 98.21% Total Trihalomethanes 52 0 0.00% 0 100.00% Other Parameters 5,320 1 0.02% 1 99.99%

All Parameters 8,505 10 0.02% 5 99.92%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 51 92,830 525 0.57% 12 31 1

107 Drinking Water Quality in Scotland 2007 South East City of Edinburgh

Water Quality in Local Authorities in the South East

City of Edinburgh Council

Water Supply Zones in Area Alnwickhill A Balmore F Hillend Alnwickhill B Fairmilehead A Marchbank A Balmore E Fairmilehead B Marchbank B

Quality of Public Water Supply

Parameter Total Total % of Number of Mean Zonal number number fails Zones with Compliance of tests of fails failures Coliform Bacteria (Total coliforms) 1,894 7 0.37% 4 99.65% E. coli (Faecal coliforms) 1,894 0 0.00% 0 100.00% Colour 623 5 0.80% 4 99.27% Turbidity 623 0 0.00% 0 100.00% Hydrogen ion (pH) 623 1 0.16% 1 99.85% Aluminium 623 0 0.00% 0 100.00% Iron 623 1 0.16% 1 99.85% Manganese 623 0 0.00% 0 100.00% Lead 104 2 1.92% 2 98.08% Total Trihalomethanes 105 0 0.00% 0 100.00% Other Parameters 12,564 13 0.10% 2 99.94%

All Parameters 20,299 29 0.14% 9 99.88%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 12 463,510 134 0.03% 1 11 1

108 Drinking Water Quality in Scotland 2007 South East Falkirk

Water Quality in Local Authorities in the South East

Falkirk Council

Water Supply Zones in Area Balmore A Carron Valley A Turret A Balmore E Carron Valley B Turret C Balmore F Glendevon A Turret/Balmore/Carron Valley Balmore G Pateshill

Quality of Public Water Supply

Parameter Total Total % of Number of Mean Zonal number number fails Zones with Compliance of tests of fails failures Coliform Bacteria (Total coliforms) 1,353 8 0.59% 4 99.37% E. coli (Faecal coliforms) 1,353 0 0.00% 0 100.00% Colour 457 0 0.00% 0 100.00% Turbidity 457 0 0.00% 0 100.00% Hydrogen ion (pH) 457 0 0.00% 0 100.00% Aluminium 461 2 0.43% 1 99.74% Iron 461 3 0.65% 3 99.32% Manganese 461 3 0.65% 2 99.61% Lead 81 0 0.00% 0 100.00% Total Trihalomethanes 81 0 0.00% 0 100.00% Other Parameters 8,540 0 0.00% 0 100.00%

All Parameters 14,162 16 0.11% 6 99.96%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 8 149,680 25 0.02% 0 8 0

109 Drinking Water Quality in Scotland 2007 South East Midlothian

Water Quality in Local Authorities in the South East

Midlothian Council

Water Supply Zones in Area Alnwickhill B Hillend Castle Moffat Rosebery Fairmilehead A Rosebery Castle Moffat Fairmilehead C Rosebery Hopes Heriot

Quality of Public Water Supply

Parameter Total Total % of Number of Mean Zonal number number fails Zones with Compliance of tests of fails failures Coliform Bacteria (Total coliforms) 834 4 0.48% 2 99.64% E. coli (Faecal coliforms) 834 0 0.00% 0 100.00% Colour 283 2 0.71% 1 99.53% Turbidity 283 0 0.00% 0 100.00% Hydrogen ion (pH) 283 1 0.35% 1 99.76% Aluminium 281 0 0.00% 0 100.00% Iron 281 1 0.36% 1 99.76% Manganese 281 0 0.00% 0 100.00% Lead 60 1 1.67% 1 98.44% Total Trihalomethanes 61 0 0.00% 0 100.00% Other Parameters 5,902 1 0.02% 1 99.99%

All Parameters 9,383 10 0.11% 5 99.93%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 68 79,290 389 0.49% 3 65 3

110 Drinking Water Quality in Scotland 2007 South East Scottish Borders

Water Quality in Local Authorities in the South East

Scottish Borders Council

Water Supply Zones in Area Acreknowe Drumelzier Rawburn Black Esk Ettrickbridge Roberton Bonchester Heriot Rosebery Bonnycraig Howden Southdean Castle Moffat Innerleithen Tweedsmuir Coulter Manse Street Yarrowfeus Dodburn Newcastleton Yarrowford

Quality of Public Water Supply

Parameter Total Total % of Number of Mean Zonal number number fails Zones with Compliance of tests of fails failures Coliform Bacteria (Total coliforms) 647 6 0.93% 5 98.91% E. coli (Faecal coliforms) 647 0 0.00% 0 100.00% Colour 271 0 0.00% 0 100.00% Turbidity 271 1 0.37% 1 99.62% Hydrogen ion (pH) 271 1 0.37% 1 99.90% Aluminium 251 0 0.00% 0 100.00% Iron 251 5 1.99% 2 98.94% Manganese 251 0 0.00% 0 100.00% Lead 107 1 0.93% 1 99.38% Total Trihalomethanes 107 1 0.93% 1 99.38% Other Parameters 6,673 3 0.04% 2 99.97%

All Parameters 9,747 18 0.18% 8 99.89%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 1,388 110,240 16,825 15.26% 151 1,237 92

111 Drinking Water Quality in Scotland 2007 South East West Lothian

Water Quality in Local Authorities in the South East

West Lothian Council

Water Supply Zones in Area Balmore A Daer A Balmore E Daer Camps Balmore F Marchbank A Carron Valley A Pateshill Coulter Pateshill/Marchbank

Quality of Public Water Supply Parameter Total Total % of Number of Mean Zonal number number fails Zones with Compliance of tests of fails failures Coliform Bacteria (Total coliforms) 1,312 8 0.61% 4 99.24% E. coli (Faecal coliforms) 1,312 0 0.00% 0 100.00% Colour 439 0 0.00% 0 100.00% Turbidity 439 0 0.00% 0 100.00% Hydrogen ion (pH) 439 0 0.00% 0 100.00% Aluminium 441 0 0.00% 0 100.00% Iron 441 2 0.45% 1 99.74% Manganese 441 3 0.68% 3 99.54% Lead 76 0 0.00% 0 100.00% Total Trihalomethanes 77 0 0.00% 0 100.00% Other Parameters 8,269 4 0.05% 1 99.98%

All Parameters 13,686 17 0.12% 6 99.95%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 46 165,700 287 0.17% 6 40 7

112 Drinking Water Quality in Scotland 2007 Islands

4.5 Drinking Water Quality in the Islands (Western Isles, Orkney and Shetland)

Treatment Works

Table 4.5-a Summary of Samples Taken from Water Treatment Works in the Islands

No. WTW not Number % WTW not % exceeding meeting Parameter Number of tests exceeding meeting regulatory standard regulatory standard requirements requirements Coliforms 2,258 4 0.18% 4 6.38% Faecal Coliforms (E.Coli ) 2,258 1 0.04% 1 2.13% Nitrite 228 0 0.00% 0 0.00% Turbidity 296 1 0.34% 1 2.13% Sample compliance at water treatment exceedence occurred at Cullivoe on Yell, works in Orkney, Shetland and Western Shetland. This treatment works is not Isles improved in 2007 (Table 4.5-a). The compliant for other parameters and is due one E.coli detection occurred at North to be replaced by Scottish Water when it Ronaldsay in Orkney, and was associated rationalises the three treatment works on with the incident of August 2007, Yell. described below. The single turbidity

Table 4.5-b Summary of Disinfection Indices at Treatment Works in the Islands

2005 2006 2007 No. WTW Included 42 34 37 Average Index 55.0 32.4 40.6 No. Indices >100 11 1 5 The disinfection index (DI) is used by the consistent the chlorine level in water DWQR to track the progress being made leaving the treatment works. Scottish by Scottish Water in improving control of Water is funded to undertake work to its disinfection processes. This is to make ensure all water treatment works have a sure that all supplies are thoroughly DI of less than 100 by 2010. Although disinfected to keep them safe, while at the regulatory sample compliance in the same time, limiting the extent to which islands has improved, there was a slight chlorine concentrations fluctuate. deterioration in performance in 2007 as Inconsistent chlorine residuals in water far as the disinfection index was leaving treatment works are a major concerned (Table 4.5-b). This is in cause of taste and odour complaints from contrast to the trend seen in other consumers. The higher the DI, the less regions.

113 Drinking Water Quality in Scotland 2007 Islands

Distribution System

Table 4.5-c Summary of Samples taken from Service Reservoirs in the Islands

Parameter Number No. containing % exceeding No. service % service reservoirs of tests coliforms or standard reservoirs not not meeting E.coli meeting regulatory regulatory requirements* requirements Coliforms 4,131 9 0.22% 0 1.89% Faecal Coliforms (E.Coli) 4,131 2 0.05% 1 1.89% *95% samples shall not contain coliforms; 100% shall not contain E.coli Microbiological compliance in the Island of coliforms (Table 4.5-c). The two Region improved in 2007. Coliforms were samples containing E.coli were both from detected at nine different storage points Holland reservoir on North Ronaldsay and but all storage points met the regulatory were associated with the August requirement that 95% of samples are free contamination incident.

Table 4.5-d DMI in the Islands – Supply Zones not scoring 100%

Water Supply Zone Name MZC MZC MZC DMI Iron Manganese Turbidity Cullivoe Shetland zone 75.00% 75.00% 100.00% 83.33% Stronsay Orkney zone 100.00% 75.00% 100.00% 91.67% Lerwick Shetland zone 87.50% 95.83% 100.00% 94.44% Kirbister Orkney zone 95.83% 100.00% 100.00% 98.61% Stornoway Western Isles zone 100.00% 95.83% 100.00% 98.61%

Islands Region - Mean DMI 99.11% 98.76% 100.00% 99.29% Cullivoe supply zone on Yell, Shetland following the initiation of enforcement scored the lowest DMI in the Islands. action by DWQR. Figure 4.5-a co-relates This was mainly due to the poor DMI and contacts to Scottish Water by performance of the works, mentioned consumers concerned about discoloured earlier. Iron and manganese failures water. depressed the DMI score in Lerwick supply zone (Table 4.5-d).

Iron was a particular issue in Lerwick, and extensive rehabilitation work is now underway. An especially severe discoloured water issue in the Lover’s Loan area of the town was resolved

114 Drinking Water Quality in Scotland 2007 Islands

Figure 4.5-a DMI and Consumer Discolouration Contacts in the Islands

115 Drinking Water Quality in Scotland 2007 Islands

Consumer Contacts September 2007. Also in Shetland, Cullivoe and South Yell supply zones, both Figure 4.5-b Consumer Contacts about on the island of Yell, experienced Drinking Water Quality in the Islands discolouration contact rates well in excess of 200 per 10,000 population. Due to the

Islands small populations involved this only Scottish Water Average equated to a total of 16 contacts, but is significant nonetheless because it is 80 mainly due to the poor performance of the 70 60 two water treatment works concerned. 50 Scottish Water has committed to 40 30 improving the situation by March 2009. 10,000 pop. 20 Ness in the Western Isles also generated Contact Rate per 10 0 a significant number of discoloured water l l l ll r el e e e ter contacts during 2007 – 65 in total, giving m m m a S S S / W / Wat e e/ e t t d ) a complaint rate of 552 per 10,000 s st e y as a a r lk T i T T u o M e ic y ( population. n l h ol i al t c d r r s e o et i hl Ea D at M / r C y e The chlorine taste and odour contact data t A us M for Scotland in 2007 is dominated by complaints from Mainland Shetland, specifically the Eela Water and Lerwick supply zones. These occurred mainly in The Island region recorded a higher rate the late Spring and Summer following a of contacts about water quality in most change by Scottish Water in the method it categories (Figure 4.5-b), but especially used to disinfect the water, when these discolouration and chlorine taste and supplies were switched from chlorination odour. To some extent this is to chloramination. Chloramination is used unsurprising as a relatively low number of to disinfect water supplies throughout the contacts in this sparsely populated area world without any problem, however the will produce a high contact rate. introduction of chloramination in these However, there were undoubtedly a two Shetland supplies triggered a large number of issues concerning the number of complaints about an acceptability of the water to consumers unpleasant taste and, in some cases, a during 2007. burning sensation. Scottish Water has investigated these complaints but the An acute but localised issue in part of solution has, to date, remained elusive. Lerwick with discoloured supplies was The number of customer contacts has resolved following mains rehabilitation dropped off significantly but it is evident work by Scottish Water after DWQR had that a number of consumers are still threatened enforcement action in

116 Drinking Water Quality in Scotland 2007 Islands unhappy with their water supply. The problem is not universal and some consumers on the supplies are content with the new arrangements, nonetheless, DWQR is committed to investigating this matter until it is resolved satisfactorily. The solution however, make take time to identify.

South Uist and Benbecula in the Western Isles recorded seven and six contacts respectively about earthy or musty tastes. Although not large numbers in themselves, they do amount to significant complaint rates per head of population for this comparatively unusual contact category.

117 Drinking Water Quality in Scotland 2007 Islands

Incidents

In 2007, two events were declared North Ronaldsay, Orkney incidents in the Islands. This is three less 08 Aug 2007 Microbiological Failure than in 2006. Following exceptionally heavy rainfall, Lemreway Western Isles E.coli and Cryptosporidium were detected 13 Mar 2007 Disinfection Failure in a number of samples taken from the supply. A boil notice was issued on 9 This incident was caused by a failure of August and lifted on 14 September once the flow meter which controls the chlorine passing samples had been obtained. dosing at this treatment works. A low Scottish Water has installed temporary chlorine alarm did go through to Scottish filtration at the site to provide protection Water’s Operational Management Centre until a permanent solution to securing and this was passed on to the standby water quality is identified. supervisor, however, due to previous false alarms, the standby supervisor decided not to pass the alarm on to the operator until the next day. He spoke to the senior operator the next morning but neither passed the alarm on to the site operator. The low chlorine was only therefore discovered during a routine visit by the operator some 31 hours after the initial alarm. A routine sample was taken early the next morning after the alarm had been sent but the sampler appears not to have informed anyone about the low chlorine residual, so this was a further missed opportunity and Scottish Water’s Public Health Team were only informed after the problem had been fixed.

Scottish Water has re-trained staff, and ensured that all alarms are attended to and that samplers report any low chlorine results to its Public Health Team. Telemetry alarms at the site have also been reviewed to ensure they are appropriate.

118 Drinking Water Quality in Scotland 2007 Islands Comhairle Nan Eilean Siar

Water Quality in Local Authorities in the Islands

Comhairle Nan Eilean Siar

Water Supply Zones in Area Ardvourlie Western Isles Hushinish Western Isles South Uist Western Isles Barra Western Isles Lemreway Western Isles Stornoway Western Isles Bayhead Western Isles Lochmaddy Western Isles Suinaval Western Isles Benbecula Western Isles Maaruig Western Isles Tarbert Western Isles Berneray Western Isles Meavaig Western Isles Tolsta Western Isles Cliasmol Western Isles Ness Western Isles West Lewis Western Isles Geocrab Western Isles Orasay Western Isles Govig Western Isles Rhenigidale Western Isles

Quality of Public Water Supply Parameter Total Total % of Number of Mean Zonal number number fails Zones with Compliance of tests of fails failures Coliform Bacteria (Total coliforms) 223 0 0.00% 0 100.00% E. coli (Faecal coliforms) 223 0 0.00% 0 100.00% Colour 92 1 1.09% 1 98.86% Turbidity 92 0 0.00% 0 100.00% Hydrogen ion (pH) 92 1 1.09% 1 97.73% Aluminium 91 0 0.00% 0 100.00% Iron 91 0 0.00% 0 100.00% Manganese 91 1 1.10% 1 99.81% Lead 67 0 0.00% 0 100.00% Total Trihalomethanes 67 1 1.49% 1 98.86% Other Parameters 3,226 2 0.06% 1 99.94%

All Parameters 4,355 6 0.14% 4 99.84%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 101 26,350 561 2.13% 59 42 53

119 Drinking Water Quality in Scotland 2007 Islands Orkney

Water Quality in Local Authorities in the Islands

Orkney Islands Council

Water Supply Zones in Area Boardhouse Orkney Sanday Orkney Eday Orkney Shapinsay Orkney Kirkbister Orkney South Hoy Orkney North Hoy Orkney Stronsay Orkney North Ronaldsay Orkney Westray Orkney Rousay Orkney

Quality of Public Water Supply

Parameter Total Total % of Number of Mean Zonal number number fails Zones with Compliance of tests of fails failures Coliform Bacteria (Total coliforms) 132 0 0.00% 0 100.00% E. coli (Faecal coliforms) 132 0 0.00% 0 100.00% Colour 58 0 0.00% 0 100.00% Turbidity 58 0 0.00% 0 100.00% Hydrogen ion (pH) 58 0 0.00% 0 100.00% Aluminium 58 0 0.00% 0 100.00% Iron 58 1 1.72% 1 99.62% Manganese 58 1 1.72% 1 97.73% Lead 39 1 2.56% 1 97.73% Total Trihalomethanes 39 1 2.56% 1 98.86% Other Parameters 1,891 2 0.11% 1 99.74% All Parameters 2,581 6 0.23% 3 99.66%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 180 19,770 462 2.34% 22 158 0

120 Drinking Water Quality in Scotland 2007 Islands

Water Quality in Local Authorities in the Islands

Shetland Islands Council

Water Supply Zones in Area Bigton Shetland Lerwick Shetland Bressay Shetland Mid Yell Shetland Cullivoe Shetland Papa Stour Shetland Eela Water Shetland Skerries Shetland Fair Isle Shetland South Yell Shetland Fetlar Shetland Unst Foula Shetland Whalsay Shetland

Quality of Public Water Supply

Parameter Total Total % of Number of Mean Zonal number number fails Zones with Compliance of tests of fails failures Coliform Bacteria (Total coliforms) 164 3 1.83% 3 97.72% E. coli (Faecal coliforms) 164 0 0.00% 0 100.00% Colour 74 1 1.35% 1 98.21% Turbidity 74 0 0.00% 0 100.00% Hydrogen ion (pH) 74 7 9.46% 4 88.39% Aluminium 74 5 6.76% 2 91.07% Iron 74 4 5.41% 2 97.32% Manganese 74 2 2.70% 2 97.92% Lead 49 0 0.00% 0 100.00% Total Trihalomethanes 49 2 4.08% 1 96.43% Other Parameters 2,405 1 4.00% 1 99.95% All Parameters 3,275 25 0.76% 8 99.23%

Summary of Private Water Supplies

Number of Total Population on % Population Number of Number of Number of Private Water population PWS on PWS Type A Type B Risk Supplies supplies supplies Assessments 74 21,880 95 0.43% 3 71 6

121 Annexes

122 Drinking Water Quality in Scotland 2007

Annex A A. The Regulatory Framework

The regulatory standards for drinking • local authorities must take water quality in Scotland largely stem appropriate steps to keep from European Directives. On 5 December themselves informed about the 1998 a revised Drinking Water Directive wholesomeness of public and (98/83/EC) was published in the ‘Official private water supplies in their area Journal of the European Communities’. and notify Scottish Water if not Member States of the European Union satisfied,. were given five years to meet the • local authorities are required to standards set in the revised Directive. secure improvements to private Exceptions to this timescale are the final water supplies if they consider standards for trihalomethanes (8 years) them necessary, and and lead (15 years). The original Drinking • Water Directive of 15 July 1980 wholesomeness is defined for (80/778/EEC) was in force prior to this public supplies in the Water Supply and was reflected in the Water Supply (Water Quality) (Scotland) (Water Quality)(Scotland) Regulations Regulations 1990 (now 2001 Regs) 1990. Scotland and the rest of the UK and for private supplies in the implemented the revised Directive before Private Water Supplies (Scotland) the end of 2003 as required by the EC. Regulations 1992.

The key regulations are:

The Water Supply (Water Quality) (Scotland) Regulations 2001 The Water (Scotland) Act 1980 • The 2001 regulations effectively • Scottish Water must supply came into force on 25 December wholesome water for domestic 2003; purposes. It is a criminal offence • to supply water unfit for human define wholesomeness by setting consumption; standards for 40 parameters and a further 11 indicator parameters; • Scottish Ministers must take • enforcement action against set and define, the supply zone as Scottish Water if it fails in its duty the basic unit for quality to supply wholesome water unless monitoring; the failure is trivial or Scottish Water is complying with a legally binding undertaking to remedy the matter;

123 Drinking Water Quality in Scotland 2007

Annex A

• specify detailed sampling The Surface Waters (Abstraction for requirements for samples taken at Drinking Water) (Classification) taps within zones, at service (Scotland) Regulations 1996 reservoirs and at water treatment • works; sets standards for the quality of surface water to be used as • require Scottish Water to publish sources of public water supply; an annual report and keep a public • register of water quality in its permits waivers for certain area; parameters where these have a natural origin; and • transpose the requirements of • Council Directive 98/83/EC of 3 requires Scottish Water to classify November 1998 on the quality of all its sources of water in water intended for human accordance with prescribed quality consumption into Scottish criteria subject to authorised legislation. waivers.

The Water Industry (Scotland) Act The Cryptosporidium (Scottish 2002 Water) Directions 2003 • • Created the post of Drinking Water the Cryptosporidium (Scottish Quality Regulator for Scotland Water) Directions 2003 came into (DWQR); force on 1 January 2004; • • DWQR is responsible for enforcing revised Directions provide for more the Water Supply (Water widespread testing for Quality)(Scotland) Regulations Cryptosporidium to provide data 2001; about background levels in water supplies; • DWQR is independent of Ministers; • provision put in place for • DWQR has powers to obtain Cryptosporidium sampling at all information, power of entry or water treatment works between inspection and power of January and June 2004; and enforcement; • from June 2004, every supply in • DWQR also has emergency powers Scotland has been required to be to require a water supplier to tested at least once a month with carry out works to ensure quality the frequency of testing being of water supplied is safe for public based on the assessed risk and the consumption. flow through the works.

124 Drinking Water Quality in Scotland 2007

Annex A

The Private Water Supplies (Scotland) Regulations 2006

• define wholesomeness in the same manner and prescribe the same standards as for public supplies in accordance with the EC Drinking Water Directive 98/83/EC;

• require local authorities to classify private supplies according to size and use;

• require local authorities to monitor private supplies in their area according to classification and risk;

• set out reporting requirements local authorities must fulfil; and

• provide for grants to enable private supply owners to make improvement.

125 Drinking Water Quality in Scotland 2007

Annex B B. Index of Information Letters / Guidance Letters issued during 2007

Information letter number Title

1/2007 The Scottish Water Information Return to DWQR – Further Guidance

2/2007 Cryptosporidium Standard Operating Protocols (SOPs) 2007

3/2007 Review of action being taken by Scottish Water on WTW where telemetry is not installed or is not operating appropriately

4/2007 Raw water monitoring requirements following the repeal of Council Directive 75/440/EEC on the quality required of surface water intended for the abstraction of drinking water

5/2007 Guidance on interpretation of Regulation 16(2)(d)(i) of the Water Supply (Water Quality)(Scotland) Regulations 2001

6/2007 Trigger values for “Priority” event reporting

Regulation 27 letter number Title

1/2007 Annual list of approved products and processes

2/2007 Changes to the approval arrangements for products under Regulation 27

Copies of these letters are available on the DWQR website: www.dwqr.org.uk/technical.html

126 Drinking Water Quality in Scotland 2007

Annex C C. Authorised Departures

There are currently some public water Water must publicise the Authorised supplies in Scotland that do not Departure either by placing an consistently meet the prescribed standard advertisement in an appropriate local for one or more parameters. Under newspaper, or, in smaller supply zones, by regulations 20 and 21 of the 2001 notifying individual customers by post. Regulations, Scottish Water may apply to The DWQR monitors progress with the the Scottish Ministers for an Authorised work undertaken by Scottish Water in Departure from one or more of the order to comply with the terms of the prescribed standard(s) in respect of a Authorised Departure to ensure that it is specified water supply. Authorised on track to achieve compliance by the Departures may not be granted for a date specified. Should progress on the period in excess of three years, nor where work give cause for concern, the DWQR a breach of the prescribed standard could may initiate enforcement action against present a risk to human health. When Scottish Water. Scottish Ministers authorise a Departure, a revised limit is set for the parameter(s) in In 2007, no new Authorised Departures question, and Scottish Water is under an were granted by Scottish Ministers, obligation to secure compliance with the however Departures were in force in 17 standard prescribed in the Regulations by water supply zones for all or part of 2007. the date specified in the Authorised Most of the supply zones with Authorised Departure. Additional monitoring for those Departures are in the North West of revised parameters, at frequencies in Scotland and have relatively small excess of those provided for in the populations, in many cases less than 20 Regulations, may also be agreed. people. Many of these supplies are small upland sources which currently have no When applying for an Authorised treatment other than chlorination. The Departure, Scottish Water must copy their solutions proposed include construction of application to every appropriate local the relevant treatment processes, or, authority, NHS board and the Water where practical, supplying the area from a Industry Commission, all of whom have an neighbouring supply which is compliant opportunity to make representations on with the Regulations. The parameters for the Authorised Departure application. which Authorised Departures have been Once an application is granted, Scottish granted are shown in the table overleaf.

127 Drinking Water Quality in Scotland 2007

Annex C

Authorised Departures in Force During 2007

Water Supply Zone Parameters Date AD Expires

Kylesku pH 31/03/2007

Torridon Colour, THM 30/06/2007

Earlish Colour 31/08/2007

Barclye THM, Colour, Iron 30/09/2007

Penwhirn Barclye THM, Colour, Iron 30/09/2007

Laide THM, Colour, Iron 14/10/2007

Aultbea THM, Colour 14/10/2007

Alligin Colour 31/10/2007

Strontian THM, Colour, Iron, pH 30/11/2007

Kinlochleven THM 31/12/2007

Penwhirn Palnure THM, Colour, Iron 31/12/2007

Tarbert Western Isles Colour 31/12/2007

Dornie THM, Colour 30/06/2008

Balmacara THM, Colour, Iron 30/06/2008

Lochinver THM 31/12/2008

Shieldaig THM, Colour 01/04/2009

Palnure THM, Colour, Iron 01/04/2009

128 Drinking Water Quality in Scotland 2007

Annex D D. Audits of Scottish Water in 2007

Operational Audits During 2007 DWQR carried out detailed Two treatment works were also audited as technical audits at three water treatment part of DWQR investigations in response works, four service reservoirs and at 11 to incidents at those sites. distribution system locations. In line with As in 2006, the water treatment works the recommendations of the Better audits incorporated compliance with the Regulation Task Force, a risk-based Cryptosporidium Directions into the approach is taken in the identification of standard works audit, resulting in the audit locations. This focuses the audits efficiency savings for both Scottish Water on those areas which are shown to have a and DWQR. higher than normal number of failures with the regulatory standards, or other factors of concern in the previous year.

Technical Audits Undertaken by DWQR in 2007

Region Water Treatment Works Service Reservoirs Distribution Systems

North East Cowdenbeath Bankfoot Aberdeen South East Marchbank Colmsliehill Bonnybridge Daer Glassford South West Bradan (Incident) Kerse Coatbridge Corsehouse (Incident) Coatbridge (Dalmacoulter) Airdrie (Dalmacoulter) Guiltreehill (Ayr) Knockjarder (Ayr) Inverkip North West Achnandaroch Letters Mid Clyth

Islands Lerwick

129 Drinking Water Quality in Scotland 2007

Annex D

Eleven audits were undertaken on some of them did not match the manual distribution systems, recognising that all tests being carried out by the operator. work on a distribution system carries an Also the turbidity meter on the outlet of inherent risk of contamination unless the first filter was reading higher than its appropriate protective measures are counterparts on the outlets of the other followed by Scottish Water and filters. DWQR found that these were still contractors. A number of issues were an issue on the re-visit so had to remind highlighted, many of which were common Scottish Water to look into the issues to several audits. The most serious again and resolve them. This was deficiencies concerned dewatering of subsequently done. excavations and sampling.

Key findings from treatment works and South West service reservoir audits are summarised by region. DWQR re-visits all sites within a At Bradan, recommendations were made year of the initial audit to ensure that concerning the urgent need for capital work has been carried out to address any maintenance of the filters as well as issues found: certain aspects of operational monitoring.

At Corsehouse, recommendations included the implementation of measures to reduce South East the impact of filter washes on water DWQR noted that there was now better quality, improving the integrity of the control of the chloramination process at contact tank and ensuring that Marchbank which should help to prevent operational water quality monitoring is the nitrite fails in distribution and that undertaken at the correct frequency. there are also plans to change the process so that chorine is added first followed by ammonia which is the more conventional North West approach for chloramination. All three service reservoirs were picked for At Daer WTW DWQR found issues with audit due to the numbers of regulatory the monitoring of turbidity. At present fails in the year leading up to the time of there is only one monitor on each of the the audit. DWQR was pleased to note that two banks of 5 filters whereas each filter Scottish Water had undertaken cleaning should have its own dedicated meter. work at both Achnandaroch and Letters DWQR note that Scottish Water will service reservoirs. Furthermore, at resolve this issue as part of the current Achnandaroch Scottish Water had work being carried out at Daer which is changed the operation such that greater due for completion in March 2009. turnover of the water was now possible to keep the water fresher and reduce the

possibility of failures. DWQR understands At Glassford DWQR also found issues with that the fails at Mid Clyth service reservoir turbidity meters, where the readings on were due to bursts in the distribution

130 Drinking Water Quality in Scotland 2007

Annex D system upstream. The reservoir was number of recommendations were made. boosted with chlorine at the time and The most significant of these concerned there have been no fails since. the way in which concerns about potential waterborne illness were dealt with, the Customer Contact Centre Audits extent to which Scottish Water offered DWQR audited the information provided information about water quality problems to consumers who contacted Scottish to consumers, and the way in which Water about water quality matters, and information concerning water quality the resulting operational response from contacts was recorded. It is anticipated Scottish Water. The audits took place in that a further audit will take place in one early 2008. Fifteen telephone and five year’s time in order to monitor the way in written contacts were audited and a which these issues have been addressed.

131 Drinking Water Quality in Scotland 2007

Annex E E. Statistical Methods Used in the Report

Water Quality Compliance Data for Local Authority Areas Zonal Compliance

In order to present drinking water quality Mean zonal compliance for any area is data by local authority area in Section 6, it built up from zonal compliance figures for has been necessary to report data for the individual parameters in individual supply group of supply zones within that area. zones. Zonal compliance is simply the Water supply zone boundaries do not fit percentage of samples meeting the PCV local authority boundaries exactly, so the for that parameter. data for any supply zone which falls Mean Zonal Compliance wholly or partly into the local authority area has been included. The Mean Zonal Compliance (MZC) for a parameter may be built up for a particular This approach means that data from some group of supply zones by taking the supply zones is included twice or more in arithmetic mean of zonal compliances for Section 6. For example, the same data for that parameter across all the supply zones Alnwickhill B supply zone appear in the of interest. MZC may be produced for a sections for East Lothian, Midlothian and City of Edinburgh. local authority area, region or for Scotland as a whole in this way. Mean Zonal Compliance Overall Compliance The DWQR used the index known as Mean Zonal Compliance for the first time in the The Overall Compliance for any group of 2005 report. It is a helpful tool when supply zones is the arithmetic mean of the considering water quality at national, MZCs for every parameter. An Overall regional and local level as it provides a Compliance figure for Scotland may be simple means of summarising drinking calculated in this way. In 2006, DWQR has water compliance and comparing year on used the same parameters in this year performance. All drinking water calculation as the other UK regulators, quality regulators in the UK are now namely the 40 parameters in Schedule 1 reporting Mean Zonal Compliance figures of the 2001 Regulations that have a using the same methodology, and it numerical standard. The full list of should therefore now be possible to make parameters may be found in Table 3.4b of comparisons of this index between the this report. In 2007 overall compliance countries of the UK. was 99.63%, in 2006 this was 99.44%.

132 Drinking Water Quality in Scotland 2007

Annex E

Pesticides

All parameters are weighted equally in the parameter per year. If one of these calculation. Scottish Water tests for a samples fails, this will adversely affect large number of different pesticides every mean zonal compliance to a much greater year, using a risk assessment process to extent than a sample failure in a large define sampling requirements in each supply zone. This is unavoidable, and in supply zone. This variation in sampling calculations of regional mean zonal requirements combined with the sheer compliance, this effect is compensated for number of pesticide determinands has the by the large number of these small zones potential to skew the Overall Compliance which are present in regions such as the calculation by placing undue weight on North West. pesticide analysis. For that reason, results Distribution Maintenance Index for the individual pesticides not specifically mentioned in Schedule 1 of the The Distribution Maintenance Index (DMI) Regulations have been pooled to produce is the same as the Operational a single “All Pesticides” parameter. Performance Index (TIM) used in previous DWQR reports. It is used to reflect the Zones with small populations performance of the distribution system for Some of the water supply zones in a zone or collection of zones, and is Scotland are very small, with populations simply the arithmetic mean of the MZCs in single figures. Regulatory sample for turbidity, manganese and iron for that frequencies are based on population, group of zones. hence sampling for certain parameters in these zones is infrequent, with perhaps only two samples being taken for each

133 Drinking Water Quality in Scotland 2007

Annex E

Worked Example

Zonal Compliance

The zonal compliance for iron for a notional supply zone, Zone 1, is calculated as follows:

No. samples No. samples Zonal Compliance taken for iron failing (Iron)

Zone 1 52 2 96.15

Mean Zonal Compliance

In order to calculate the MZC for iron for a group of 10 zones which include Zone 1, the arithmetic mean of all the zonal compliances for iron is taken.

Zone 1 96.15

Zone 2 98.6

Zone 3 100

Zone 4 100

Zone 5 100

Zone 6 100

Zone 7 100

Zone 8 100

Zone 9 100

Zone 10 100

MZC 99.48

Overall Compliance

To calculate overall compliance for the group of 10 zones, the arithmetic mean of the MZC for every parameter is calculated.

134 rnigWtrQaiyi ctad20 nulRpr yteDikn ae ult Regulator Quality Water Drinking the by Report Annual 2007 Scotland in Quality Water Drinking I am concerned about the quality of my drinking water in my home or Drinking Water place of work. What can I do? Quality in Scotland 2007 Annual Report by the Drinking Water Quality Regulator In the first instance you should contact Scottish Water and ask them to investigate.

Scottish Water PO Box 8855 Edinburgh EH10 6YQ

Tel 0845 601 8855

If, having discussed the matter with Scottish Water, you do not feel that the issue has been satisfactorily resolved, you should contact the Drinking Water Quality Regulator for Scotland. The DWQR can investigate on your behalf and take action if necessary. DWQR will inform you of the outcome of any investigation.

The DWQR may be contacted either by writing to:

Drinking Water Quality Regulator for Scotland PO Box 23598 EDINBURGH © Crown copyright 2008 EH6 6WW This document is also available on www.dwqr.org.uk Or emailing [email protected] RR Donnelley B56313 07/08 Or telephoning 0131 244 0224 Further copies are available from When contacting DWQR, please provide as much information as possible, including the Blackwell's Bookshop address of the property where the problem has occurred, the nature and duration of your 53 South Bridge concerns and details of any contact you have had with Scottish Water regarding the problem. Edinburgh Please note that the DWQR can only investigate concerns relating to the quality of public EH1 1YS drinking water supplies in Scotland. For matters concerning private supplies in Scotland you should contact the Environmental Health Department of your local council. Telephone orders and enquiries 0131 622 8283 or 0131 622 8258 For matters concerning services provided by Scottish Water other than the quality of the water supplied you should contact Waterwatch Scotland: [email protected] Fax orders 0131 557 8149 For matters concerning the quality of public supplies elsewhere in the UK you should contact the Drinking Water Inspectorate (DWI) for England or Wales or the Northern Ireland Drinking Email orders Water Inspectorate. The DWQR works closely with both of these organisations to ensure a [email protected] consistent approach is taken towards ensuring the quality of drinking water across the UK. A Memorandum of Understanding between the three bodies can be found on the DWQR website: www.dwqr.org.uk

www.dwqr.org.uk The 10 Key Drinking Water Quality Standards in Scotland Ten key drinking water quality standards have been identified from the Water Supply (Water Quality) (Scotland) Regulations 2001 which are of particular significance when considering the quality of drinking water in Scotland.

Parameter Significance

Total Coliforms The coliform group of bacteria is present in large numbers in the gut of all PCV 0 per 100ml warm-blooded animals and in the environment. Their presence in water supplies Sampled at WTW, service may indicate a breach in the integrity of the water supply system or a failure of the reservoirs and at consumers’ treatment process, and they are a useful indicator in monitoring the quality of water taps. supplies. It is generally considered that coliforms themselves do not present a risk to health, and on their own they do not indicate that faecal pollution has occurred.

Faecal Coliforms Faecal coliforms are present in large numbers in the gut of all warm-blooded PCV 0 per 100ml animals. Their presence in water supplies indicates a breach in the integrity of the Sampled at WTW, service water supply system and that faecal pollution may have occurred. The detection of reservoirs and at consumers’ faecal coliforms in a water supply is taken very seriously. taps.

Colour True colour in water comes from naturally occurring humic substances, particularly PCV 20 mg/L Pt/Co in acidic water sources derived from peaty moorland catchment areas with minimal Sampled at consumers’ taps. treatment. High colour may be unacceptable to consumers on aesthetic grounds and the humic substances may form other compounds such as trihalomethanes when the water is disinfected.

Turbidity Turbidity is a measure of the “cloudiness” of the water. Naturally occurring turbidity PCV 4 NTU is usually caused by the suspension of tiny particles of predominantly inorganic Sampled at consumers’ taps origin. Its presence could indicate poor control of the treatment process and could (1NTU standard applies at mean that the treatment process has not provided an effective barrier against treatment works). organisms such as Cryptosporidium, or that disinfection has been compromised.

Hydrogen Ion (pH) pH is a measure of the hydrogen ion content of the water or degree of acidity. PCV 6.5 – 9.5 Most surface waters in Scotland have a low pH and would therefore be corrosive Sampled at consumers’ taps. towards the materials used in water treatment systems and consumers’ installations unless corrected during treatment. Extreme pH values may present a risk to the health of consumers.

Aluminium Aluminium occurs in acidic waters derived from moorland catchments and is PCV 200 µg/l removed in water treatment by coagulation and filtration. Aluminium sulphate is Sampled at consumers’ taps. used as a coagulant in water treatment. High concentrations are unacceptable to consumers on aesthetic grounds.

Iron Iron is present naturally in many water sources and is removed by conventional PCV 200 µg/l water treatment processes. Iron in water supplies may also be derived from Sampled at consumers’ taps. corrosion of iron water mains and poor control of water treatment processes. High iron concentrations are unacceptable to consumers on aesthetic grounds as they may cause discoloured supplies.

Manganese Manganese occurs naturally in many water sources. It may be removed from water PCV 50 µg/l by using an appropriate treatment process. Where treatment processes do not Sampled at consumers’ taps. remove manganese, it may accumulate in water mains and cause unacceptable discolouration of supplies.

Lead Elevated lead concentrations may be present at consumers’ taps if lead pipes have PCV 25 µg/l been used in the internal household plumbing or service pipe. Many waters in Sampled at consumers’ taps Scotland have a tendency to dissolve lead from lead pipework, and phosphate (reduces to 10µg/l in 2013). compounds can often be dosed at the treatment works to reduce this tendency.

Trihalomethanes Trihalomethanes (THMs), occur in drinking water principally as products of the PCV 100 µg/L for total of four of reaction of chlorine with naturally occurring organic materials such as humic acids. the compounds. Treatment processes can be adapted to minimise their formation or to remove the Sampled at consumers’ taps. precursor compounds. THMs at high concentrations may present a health risk if consumed over a long period. ae ult nSoln 07Ana eotb h rnigWtrQaiyRegulator Quality Water Drinking the by Report Annual 2007 Scotland in Quality Water Drinkin g I am concerned about the quality of my drinking water in my home or Drinking Water place of work. What can I do? Quality in Scotland 2007 Annual Report by the Drinking Water Quality Regulator In the first instance you should contact Scottish Water and ask them to investigate.

Scottish Water PO Box 8855 Edinburgh EH10 6YQ

Tel 0845 601 8855

If, having discussed the matter with Scottish Water, you do not feel that the issue has been satisfactorily resolved, you should contact the Drinking Water Quality Regulator for Scotland. The DWQR can investigate on your behalf and take action if necessary. DWQR will inform you of the outcome of any investigation.

The DWQR may be contacted either by writing to:

Drinking Water Quality Regulator for Scotland PO Box 23598 EDINBURGH © Crown copyright 2008 EH6 6WW This document is also available on www.dwqr.org.uk Or emailing [email protected] RR Donnelley B56313 07/08 Or telephoning 0131 244 0224 Further copies are available from When contacting DWQR, please provide as much information as possible, including the Blackwell's Bookshop address of the property where the problem has occurred, the nature and duration of your 53 South Bridge concerns and details of any contact you have had with Scottish Water regarding the problem. Edinburgh Please note that the DWQR can only investigate concerns relating to the quality of public EH1 1YS drinking water supplies in Scotland. For matters concerning private supplies in Scotland you should contact the Environmental Health Department of your local council. Telephone orders and enquiries 0131 622 8283 or 0131 622 8258 For matters concerning services provided by Scottish Water other than the quality of the water supplied you should contact Waterwatch Scotland: [email protected] Fax orders 0131 557 8149 For matters concerning the quality of public supplies elsewhere in the UK you should contact the Drinking Water Inspectorate (DWI) for England or Wales or the Northern Ireland Drinking Email orders Water Inspectorate. The DWQR works closely with both of these organisations to ensure a [email protected] consistent approach is taken towards ensuring the quality of drinking water across the UK. A Memorandum of Understanding between the three bodies can be found on the DWQR website: www.dwqr.org.uk

www.dwqr.org.uk