Private Water Supplies Regulation and Risk Assessment

Transcription

1 Private Water Supplies Regulation and Risk Assessment Phil Smart Inspector Drinking Water Inspectorate September 2014

2 The Drinking Water Inspectorate (DWI) Regulator of quality of public drinking water supplies in England and Wales DWI provides technical advice & support to Local Authorities on private water supplies in various ways. Also acts as collection point for data returns, including sample results for EU reporting and national monitoring purposes.

3 Private water supply enquiries to DWI 2013

4 Public vs Private supplies UK Population served Responsibility of Regulated by Regulations PUBLIC Supplies 99% (54 million people) 26 licensed water companies DWI The Water Supply (water quality) regulations 2009 (as amended) PRIVATE supplies 2% (1 million residents) owners and users Local Authoritie s The Private Water Supplies Regulations 2009 (2010 in Wales)

5 Private water supplies A risk to public health? In Scotland in 2006 it was shown that 30% of 1750 samples from pws taken between 1992 and 1998 contained E.coli. 23% of samples (2,650) contained E.colibetween 2006 and Between 2006 and 2008: 48 confirmed clinical cases of E.coli 0157 infections in which contamination of a pws was either confirmed or suspected. In England and Wales, data collected by 150 LAs between 1996 and 2003 covering 11,200 pws, 19% of samples (35000 samples taken) contained E.coli 36 % of water related disease outbreaks were associated with private supplies

6 Impact on public health Strong link between private supplies and outbreaks of water borne illness in UK (Scotland 46%, England 36%) Children < 10 yrs are 3.7 times more likely to suffer diarrhoea if home is served by private supply with faecal indicators

7 In the good old days (1991 Regulations) Information held on a local level No checks on the accuracy or completeness of these records No impartial scrutiny of the adequacy of monitoring or enforcement No transparency regarding quality for the wider public, government, or those with responsibility for public health protection UK was unable to report to EU on the quality of PWS in England and wales, a duty of the UK government Quality assessment was based on monitoring alone. No provision for improving supplies

8 Legislative Framework European Drinking Water Directive 98/83/EC Applies to Private and Public drinking water supplies National Private Water Supply Regulations 1999, 2009/10 National Water Industry Act 1991, Water Act 2003 High level responsibilities of water companies and local authorities (duties, enforcement powers) [Private & Public supplies] Defines domestic purposes and relevant person

9 The relevant person The relevant person defined in Water Industry Act 1991 as: 1. owners/occupiers of premises 2. any other person who exercises powers of management or control 3. any person who owns land where water source arises

10 Scope of PWS Regulations All private water supplies used for domestic purposes as defined in Section 218 of the Water Industry Act 1991 i.e. drinking, washing, cooking, central heating & other sanitary purposes Water used solely for cattle, horses is notwithin scope of the Regulations

11 Scope continued Tourist features/public springs/grotto where they are intended for human consumption and made available to the public and/or encourage the public to drink the water. All water used in food-production for the manufacture, processing, preservation or marketing of products or substances intended for human consumption [where the water is incorporated into the food product i.e. brewing].

12 Temporary events Some temporary events are private water supplies boreholes, wells etc so would be within scope of the regulations. Where mains fed, revised guidance states that temporary events not automatically a pws (under reg 8) unless criteria are met. Regulated under the water fittings regulations by the local water company LAs should require organisers to comply with relevant codes of practice e.g. BS8551

13 The 2009/2010 Regulations in summary Water must be wholesome as defined in Regulation 4 The regs classify pws (boreholes, springs, wells) according to their size and usage (Regs 9 and 10), The regs encompass mains water that is further distributed as private supplies (reg 8). LAs are required to carry out risk assessments and monitoring on all small and large/commercial/public supplies every 5 years, and Regulation 8 supplies on a risk basis.

14 The 2009/2010 Regulations in summary (continued) The Regulations give powers of enforcement to LAs (to serve notices regulation 18 and Section 80 of the WIA). RAs, monitoring and investigations are chargeable to owners up to a stated maximum. LAs are compelled to keep pws records in their respective areas. Products and substances in contact with water must be approved for use underregulation 31 of The Water Supply (Water Quality) regulations 2009 (as amended.

15 A risk based approach In 2004, the WHO Guidelines for Drinking Water Quality recommended that water suppliers develop and implement "Water Safety Plans" (WSPs) in order to systematically assess and manage risks. Since this time, governments and regulators, water suppliers and practitioners have increasingly embraced this approach

16 A risk based approach The most effective means of consistently ensuring the safety of a drinking water supply is through the use of a comprehensive risk assessment and risk management approach that encompasses all steps in water supply from catchment to consumer. WHO, 2009 So, it s not just about monitoring

17 Risk assessment Regulation 6 requires a risk assessment to be carried out on all supplies (except single domestic dwellings) every 5 years. Purpose to establish if there is a significant risk of supplying water that is an actual or potential danger to human health. RA must be carried on a single domestic dwelling if owners requests it.

18 DWI risk assessment tool DWI developed a new RA tool in refined and covered by a Non Commercial Government Licence. Prototypes trialed by 9 local authorities Source to tap Incorporates guidance for each hazard Takes existing control measures into place when determining a risk rating Action plans are developed from high risks

19 Risk assessment process Hazards are identified, source to tap (including management and maintenance of the supply) A risk rating (VH, H, M, L) for each hazard is determined by multiplying a likelihood score with a severity score. High and very high risk hazards are grouped into an action plans, which are developed in 3 steps:

20 Catchment hazards

21 Borehole head works what it should look like

22 Before and after

23 Storage tank/chambers hazards

24 Distribution hazards Public service reservoir Surrounding catchment is mainly arable farmland Car park Animal enclosures Private land rented for craft workshops Office Duck enclosure pond Pets' corner Farm produce shop toilets cafe Fuel store Redundant pipe Hand washing tank Cross connection Leased land used as an animal park Cow field Septic tank Artists workshop Area in dotted line represents a rural estate owned by local gentry Borehole trough Public main

25 Common hazards in private water supplies treatment Section L - TREATMENT PLANT: Plant Design (i.e. excluding point of use devices in dwellings or premises) L1 Is there adequate Cryptosporidium treatment in place? L2 Is the treatment plant operating within the design capacity? L3 Is it possible to by-pass any stage of treatment? L4 Where there is a blending facility, is there an appropriate blending strategy? L5 Are there frequent flow variations through the treatment plant, which render the treatment process inadequate? L6 Are there frequent demand variations, which could cause insufficiency? Safe water pack on website adapted from Wilts Council allows owners to provide info up front

26 Management & maintenance

27 Monitoring -Current status based on Monitoring under 2009/10 Regulations 7.0% of tests not meeting standards in 2013 compared to 9.6% in 2010 Compares to 0.03% of tests from Public supplies not meeting standards in 2013 compared to 1.6% in 1991

28 Compliance Public vs private supplies

29 More information? PWS Chief Inspector Reports (figures and many case studies) DW Private Water Supplies website: Includes various guidance, notice templates, example case studies.

30 DWI Contact Details Drinking Water Inspectorate Ergon House Horseferry Road London SW1P 2AL : : dwi.enquiries@defra.gsi.gov.uk :