Drinking Water 2017
Total Page:16
File Type:pdf, Size:1020Kb
Drinking water 2017 Summary of the Chief Inspector’s report for drinking water in England July 2018 A report by the Chief Inspector of Drinking Water This page is intentionally blank Summary of the Chief Inspector’s report for d rinking water in England Drinking water 2017 Chief Inspector’s report for drinking water in England 1 Drinking water 2017 Published by Drinking Water Inspectorate Area 7e 9 Millbank c/o Nobel House 17 Smith Square London SW 1P 3JR Tel: 0300 068 6400 Website: http://www.dwi.gov.uk © Crown Copyright 2018 ISBN: 978-1-911087-24-3 Copyright in the typographical arrangement and design rests with the Crown. This publication (excluding the logo) may be reproduced free of charge in any format or medium provided that it is reproduced accurately and not used in a misleading context. The material must be acknowledged as Crown copyright with the title and source of the publication specified. 2 Summary of the Chief Inspector’s report for d rinking water in England Drinking water 2017 Summary of the Chief Inspector’s report for drinking water Drinking water 2017 is the annual publication of the Chief Inspector of Drinking Water for England and Wales. It is the 2 8 th report of the work of the Inspectorate and presents the summary information about drinking water quality for the calendar year of 201 7. It is published as a series of four quarterly reports which cover public water supplies and one report which covers private water supplies. This report is a summary of public water supplies for England. Set out in this report are the key facts about the qual ity of the public water supplies in England, which is served by 27 water companies delivering supplies to 55 million consumers. The area served by each water company is shown in Figure 2. Table 1: Key facts about public and private water supply arrangemen ts in England Public supplies Private supplies Population supplied 55,535,874 Population supplied 572,107 Water supplied (l/day) 13,863 million Water supplied (l/day) 382million Abstraction points 2,125 Approximate number of private Treatment works 1,101 water supplies* Service reservoirs 3,802 Total number of local 365 Water supply zones 1,497 authorities Length of mains pipe 315,110 Number of local authorities 256 (km) with private supplies Water composition Water composition Surface sources 64.5% Surface influenced supplies 21% Groundwater sources 30% Groundwater sources 60% Mixed sources 5.5% Mains water 15% Unknown 4% Changes to water supply arrangements in 2017 in England were that on 19 April 2017, Icosa Water Limited, a new licensee, to ok on supplies to properties in West Raynham, Norfolk. 3 Drinking water 2017 Figure 2: Company supply areas 4 Summary of the Chief Inspector’s report for d rinking water in England Drinking water quality testing Throughout 2017, water companies sampled drinking water to verify compliance with the drinking water Regulations. Almost half of the tests were carried out on samples drawn from consumers’ taps selected at random. For monitoring purposes, company water supply areas are divided into zones. Sampling in zones at consumers’ taps is risk -based with the number of tests being higher in zones with a large population (maximum 100,000). Other sample locations are water treatment works and treated water (service) reservoirs. Collectively, the water companies in England carried out a total of 3,479,642 tests during 2017 and only 1,174 of these tests failed to meet one or more of the standards set down in the Regulations or exceeded a screening value. The Inspectorate reviews the numbers of samples provided against the target number the company were required to tak e in order to identify any shortfalls. In 2017, there were no significant shortfalls (see Table 3) . Table 3: Number of tests carried out by companies in England Number Target of tests Place of sampling number of per tests Company company Water Service Consumers’ treatment reservoirs taps (zones) works Affinity 40,304 32,755 84,233 157,292 157,551 W ater (95) (156) (87) 0 0 692 Albion Water 692 693 (0) (0) (2) Anglian 113,881 78,807 139,110 331,798 331,798 W ater (140) (316) (164) 15,290 47,786 40,339 Bristol Water 113,475 113,483 (16) (160) (27) Bournemouth 12,347 5,185 18,439 35,971 35,976 W ater (7) (20) (10) Cambridge 10,068 6,345 8,518 24,931 24,979 W ater (20) (31) (8) 608 260 364 Cholderton 1,232 1,270 (1) (1) (1) Dee Valley 5,492 312 3,965 9,769 9,813 W ater (2) (1) (4) Dŵr Cymru 4,426 7,529 6,057 18,012 18,068 Welsh Water (6) (27) (12) Essex and 21,523 19,620 53,231 Suffolk 94,374 94,441 (21) (99) (44) W ater 0 0 177 Icosa Water 177 177 (0) (0) (1) 5 Drinking water 2017 Table 3: Number of tests carried out by companies in England (continued) Number Target of tests Place of sampling number of per tests Company company Water Service Consumers’ treatment reservoirs taps (zones) works Independent 0 0 2,647 W ater 2,647 2,647 (0) (0) (10) Networks Northumbrian 39,155 51,899 71,449 162,503 162,529 Water (34) (203) (64) Portsmouth 10,366 7,838 17,882 35,631 35,668 W ater (19) (31) (13) 0 0 277 Leep W ater 277 304 (0) (0) (1) 11,203 7,148 16,308 SES W ater 34,659 34,659 (7) (35) (20) South East 57,904 58,102 75,587 195,593 195,593 W ater (85) (231) (72) Southern 67,768 54,563 100,267 222,598 222,699 W ater (83) (204) (74) 0 0 8,427 SSE W ater 8,427 8,444 (0) (0) (20) South 22,370 8,268 35,332 Staffordshire 65,970 66,045 (20) (34) (20) W ater South West 46,127 66,040 67,245 179,412 179,466 W ater (32) (259) (32) Severn Trent 110,817 120,517 218,627 449,961 450,621 W ater (126) (469) (189) Thames 95,138 83,880 269,502 448,520 448,674 W ater (95) (379) (252) United 94,003 89,630 191,544 375,177 375,229 Utilities (78) (355) (226) Veolia Water 900 1,318 548 2,766 2,766 Projects (2) (6) (1) W essex 47,726 80,842 44,310 172,878 172,950 W ater (67) (319) (78) Yorkshire 87,416 89,000 151,819 328,235 328,235 W ater (58) (353) (65) England 931,497 917,189 1,630,956 3,479,642 3,474,778 total (1,014) (3,689) (1,497) Note: Numbers in brackets reflect the number of works, reservoirs or zones operated by that company in En gla nd i n 20 1 7. Some companies are permitted to carry out some tests on samples taken from supply points rather th an from consumers’ taps. 6 Summary of the Chief Inspector’s report for d rinking water in England Measuring Compliance with standards In 2017, the figure for public water supply compliance with the European Union (EU) Drinking Water Directive in England was 99.96% and also for the industry across England and W ales. This mean zonal compliance figure (MZC) remains largely unchanged since 2004 but represents the high standards for compliance in England and Wales recorded since 1990 . This figure is made up of tests for 39 different microbiological and chemical parameters, and for 21 of these parameters in England met the standard for compliance with the regulations in relation to every test. Tests taken, numbers of failures and company figures are provided in Tables 7 and 8. In 2016, the Inspectorate introduced the Compliance Risk Index (CRI), a new water quality measure. This measure is required to replace the current Mean Zonal Compliance (MZC) Index for a number of reasons . Recent amendments to regulations transpose the requirements of the drinking water directive that allow companies to move away from the current monitoring programme (based on sample numbers) to a risk -based monitoring methodology meaning that companies will be able to request adjustments to the sampling programme based on risk assessment. Over the next few years, as companies use risk -based monitoring to introduce or remove parameters from their schedule , this would add greater variability to the MZC compliance measure, making comparison more difficult. The Compliance Risk Index is a measure designed to illustr ate the risk arising from treated water compliance failures and it aligns with the current risk-based approach to regulation of water supplies used by the Drinking Water Inspectorate (DWI). Unlike MZC, it assigns a value to the significance of the failing parameter, the proportion of consumers potentially affected and an assessment of the company response . The following equation describes the calculation: The introduction of CRI creates an understanding of the seriousness and impact of those failures wit hout changes in sample numbers influencing percentage values since it only includes scores for those tests which fail. In 2017, the CRI for England and Wales was 3.56 which is an improvement from 4.78 in 2016. The improving figure is a result of a reduction in the total numbers of failures, reductions in those compliance failures which are more serious, fewer consumers potentially affected by those failures, the company responding in a way to secure future compliance or a combination of these. Similarly the improvement in England was from 5.19 to 3.62 and in Wales alone from 3.55 to 2.63.