guardians of drinking water qualityDRINKING WATER INSPECTORATE

Drinking Water Safety Plans

Implementation in England and Wales

Claire PollardDrinking Water Inspectorate

28th & 29th February 2012

Presentation Outline• WHO Guidelines• Water supply arrangements in UK• Legislation in England & Wales• Introduction of Water Safety Plans - Public water

supplies• Approach to risk assessment/risk management • Delivering risk mitigation• Positive [& negative] outcomes• Issues & challenges• Private Water Supplies

World Health Organisation (WHO) Guidelines• In 1983 – 1984 and in 1993 – 1997, WHO published 1st

& 2nd editions of Guidelines for Drinking Water Quality as successors to WHO International Standards

• The 3rd Edition was published in 2004• Describes a “Framework for Water Safety”

encompassing functions of suppliers, regulators & surveillance agencies (i.e. Health Protection Agencies)

• Framework based on a Water Safety Plan (WSP) for risk assessment & risk management of water supplies

• Provides for a rolling review & update of guideline values

World Health Organisation (WHO) Guidelines

• WHO published 4th Edition on 4 July 2011• Consolidates advice on implementation of risk

based approach to management of drinking water supplies using a water safety plan approach

• Changes to some guideline values – mostly relaxing the standard i.e. acrylamide, antimony, benzene, boron, nickel, selenium

• Tighter standards for cadmium, vinyl chloride• New standards proposed i.e. DBP (chlorite &

chlorate), NDMA

UKpublicsupplies

4 regions

ScotlandNorthern IrelandWalesEngland

UK water supply arrangements

Ownership/Organisation:• Public water supplies - provided by a licensed

(statutory) water supplier• private ownership E & W [27 licensed water suppliers], • public ownership NI & S [each with one water

company]

• Private water supplies -not provided by licensed water supplier (many used for commercial or public activities)• owned and operated by individuals, groups of people,

organisations (rarely publicly owned)

Population served by public & private supplies

England & Wales: • 99% population served by public supplies• 1% on private supplies [53, 945 discrete supplies]

Scotland:• 97% population served by public supplies• 3% on private water supplies [19,177 discrete supplies]

Northern Ireland:• 99.6% population served by public water supplies• 0.4% on private water supplies [4116 discrete supplies]

Water Quality LEGISLATION – England & Wales

Three levels of legislation:• EC Directive

• 80/778 on the quality of water intended for human consumption. (Prior to this there were no numerical standards other than the WHO guidelines)

• 98/83/EC on the quality of water intended for human consumption [introduced standards based on WHO guidelines]

• National Primary Legislation• Water Act 1989• Water Industry Act 1991• Water Act 2003

• National Secondary Legislation• Water Supply (Water Quality) Regulations 1989 • Water Supply (Water Quality) Regulations 2000/2001• Water Supply (Water Quality) Regulations 2000 (2001 in Wales)

(Amendment) Regulations 2007• Water Supply (Water Quality) Regulations 2010 [Wales]• Private Water Supplies Regulations 2009

Primary LegislationWater Act 1989:

• Established model of privatised water companies & water industry regulators

Water Industry Act 1991 & Water Act 2003• Water companies duty to supply wholesome water• Secretary of State [for environment, food & rural affairs] has

power to • make regulations• appoint a Chief Inspector of Drinking Water

• Secretary of State’s duty to enforce when breach of regulations

• Chief Inspector has power to prosecute for supply of water unfit for human consumption

Secondary Legislation [Public supplies]

Water Supply (Water Quality) Regulations 2000 (2001 in Wales)

• Defines wholesomeness by reference to water quality standards - Based on 1998 EC Drinking Water Directive

• Defines requirements for:• Monitoring i.e. Sampling points & frequencies • Analytical requirements • Level of water treatment & disinfection • Approval of substances and products• Records Provision and publication of

information

The Drinking Water Inspectorate (DWI)

• Established in 1990 (privatisation]• Regulator of drinking water quality for England and

Wales [public supplies]• Ensures that drinking water suppliers meet

requirements laid out in legislation.• Enforces when there are breaches of the

regulations.• Prosecutes when water ‘unfit for human

consumption’ is supplied• Provides technical advice to Government• Reports to the Secretary of State, Welsh Assembly

Government and the European Commission

Private supplies

DWI

EA

OFWAT

Local Authorities

Health Authorities

Public supplies 27 water companies

Consumers

1%

99%

Current Regulatory Framework in England & Wales

Drinking water 2009

Compliance with drinking water standards [Public supplies]

So why WSPs?

• >99.96% compliance but……..• Reactive approach based on end point

monitoring • Too much emphasis on treatment • Too many incidents• Too many “significant” failures• Stakeholders not communicating• Consumer confidence undermined • Challenges – competition, new owners, re-

organisations, sub-contracting etc

Four 99% compliant waters, but forget the tests, which one would you drink?

July 2009 Drinking water 2008

• Number classified as incidents in 2008 = 144

Incidents reported to DWI from 2001 to 2008

Implementation in England and Wales – Where did we start?

• DWI has been an advocate of WSPs since the launch of the 3rd edition Guidelines for ensuring the safety of drinking water supplies [2004]

• Between 2004 to 2008, DWI encouraged water suppliers to adopt a WSP approach on an informal basis.

• Encountered resistance to implementation of the approach at the start

• Risk assessment and risk management became a regulatory requirement [for public water supplies] from December 2007.

Amendment to the Regulations

• The Water Supply (Water Quality) (Amendment) Regulations 2007 came into force 22 December 2007

• Notable changes include:• The introduction of two regulations (27 & 28)

requiring water companies to carry out risk assessments and report outcome to DWI

• Guidance to the regulations recommended approach to risk assessment and risk management should be based on the WHO’s WSP approach.

• No change to the drinking water quality standards set out in 2000/2001 Regulations

Regulation 27• Every water supplier must carry out a risk assessment of each of its

treatment works & connected supply system in order to establish whether there is a significant risk of supplying water from those works or supply system that could constitute a potential danger to human health;

• Risk assessment should follow WHO WSP approach [source to tap]• Where a significant risk of supplying water that could be a potential

danger to human health is identified, [i.e. when WSP residual risk is considered unacceptable in nature], the supplier must identify further action that is required to control or mitigate the risk.

• Every water supplier shall keep its risk assessments under review. • DWI can serve a notice on a water supplier to carry out a risk

assessment or a review of an existing risk assessment by a date specified.

Regulation 28• Once a water supplier has carried out a risk assessment under

regulation 27, it must submit to DWI a report of the assessment.• The report must contain:

• a description of the risk assessment methodology; • a statement confirming where there is no significant risk of supplying

water constituting a potential danger to human health; and details of the validation and other monitoring of any existing control measures.

• Where the assessment establishes that there is a significant risk of supplying water that could constitute a potential danger to human health, the report must contain • details of every risk or potential risk that has been identified; and • details of the measures that the water supplier intends to take to

mitigate the risk. • DWI can issue a Notice requiring the water supplier to take certain

measures for a period of time to mitigate the risk including to prohibit supply until specified conditions are satisfied

The Water Safety Plan Approach - Expectations

• WHO Water Safety Plan approach to identify actual & potential hazards in catchment, at treatment works, in distribution and at consumers’ taps

• Assessment of short, medium & long term control measures required for each hazard identified

• Establish whether need for investment to mitigate risk either in the area of catchment control, or with treatment at works or in the distribution systems or perhaps combinations of these.

Risk Characterisation

• Many different approaches to risk assessment adopted. Each company has a different risk assessment methodology based on the WHO approach.

• Most are based on the basic 5x5 matrix of consequence x likelihood.

• In order to use any risk characterisation model effectively and consistently, clear definitions and guidance are required.

• At the start of Water Safety Planning in England and Wales, risk assessment was based on expert knowledge as well as data and evidence (not strictly quantitative).

Types of risk identified

• Nitrates and Pesticides (raw water source)• Pathogens (Cryptosporidium)• Lead (consumers taps)• Contamination of service reservoirs (TC/EC)• Concessionary supplies (Variety)• Taste and odour• Raw water deterioration (raw water colour

& impact on THM formation)• Discolouration in zones (Iron and

Manganese mainly due to pipes)

Initial findings from implementation of RA/RM

• A risk assessment report for every public water supply system was received by 1 October 2008(over 800 reports).

• Over 900 actions (short, medium & long term) related to mitigating risks to human health identified by the 27 water companies.

• Actions related to catchments, treatment works, distribution systems and domestic/commercial properties & were set out in Action Plans

• Risk assessments informed investment requirements for the financial period 2010 - 2015

Delivering Risk Mitigation

• All actions identified to mitigate risk to human health were formalised into legally binding contracts for delivery i.e. Undertakings or Notices (statutory instruments)

• At end of 2010, 251 of the 917 actions were Notices and 138 were Undertakings.

• The remaining actions (528) are being delivered by companies following the self regulation model.

Positive Outcomes• Improved liaison with other stakeholders such as the

Environment Agency, Health Protection teams and Local Authorities

• Greater clarity of ownership and responsibility for risks from catchment to tap

• Incorporation of proactive risk management in all aspects of water suppliers’ operations

• More robust contingencies requiring commitment & agreements between suppliers

• Ability to influence organisations to cooperate in the production of particular control measures (consumer communications strategy)

• Reports are used as a resource to compliment DWI’s day to day activities including audits, investigations, compliance assessments etc

Negative Outcomes

• Variation in interpretation of what constitutes a risk to human health• Microbiological contamination at service reservoirs

[presence of Total Coliforms]• Organics/colour – not an obvious risk by potential for

DBP formation i.e. THM• Lead – identified as a ‘future’ risk but not a current risk

[assessment based on compliance with standard]

• Some suppliers not looking at longer term position i.e. potential future risks

Experiences to date: Issues

• Companies based their WSPs on the WHO Guidelines but they all tailored the approach to fit their business, hence 27 very different risk assessment report styles

• The scope for insufficiently implementing WSPs is huge (one supplier created a methodology and then didn’t follow it!)

• Many companies struggled to put together a comprehensive communication strategy for stakeholders and consumers

Challenges• The main challenge has been getting the WSP

implemented fully and embedded in the water suppliers operations (& not a stand alone exercise)

• Also challenging to get cooperation from some organisations that may hold information that can be used to improve risk assessment

• Ability to influence organisations to cooperate in the production of some controls (consumer communications strategy)

• For DWI, challenge on resources to review and assess large volume of reports which are all in very different styles.

Private Water Supplies [E & W]• 1% of the population on private supplies (not ‘mains’

supply)• Management/control is not a licensed water supplier• Private Water Supplies Regulations 2009 introduced

risk based approach similar to public supplies regulation

• Local authorities responsible for carrying out risk assessment, monitoring & taking enforcement action to improve supplies

• DWI provides technical advice & support to Local Authorities .

Private Water Supplies Regulations 2009 - Risk assessment

Private supplies:• Every local authority must carry out a risk

assessment every five years to establish whether there is significant risk of supplying water that would constitute a potential danger to human health

• If any private supply constitutes a potential danger to human health, a local authority must serve a notice on the relevant person(s) to .........prohibit or restrict supply....inform consumers and specify remedial actions”

Private Water Supplies - situation in 2010

• 349 Local Authorities are responsible for carrying out the risk assessment of PWS

• Approx 54,000 PWS in total• Approx 34,000 are single dwellings and are

not covered by the regulations• 20,000 PWS will require risk assessment by

2014

Case Study:Before introduction of risk assessment

• Borehole serving 23 domestic dwellings• Failure for E. Coli in annual sample • Remedial action was to install chlorination • Immediately afterwards sample taken and

satisfactory • No risk assessment• Root cause not addressed • No requirement for ongoing management &

control of disinfection system • Achieved a satisfactory annual sample but did not

make the supply safe.

Case StudyAfter introduction of Risk Assessment

• Local authority risk assessment carried out • Uncontrolled risks (deficiencies) were

identified • Open bore head works allowing ingress of

contaminants• Lack of vermin protection on reservoir out flows• No basic maintenance or management

• Supply deemed a potential danger to human health and Notice served on relevant person (owner)• Users informed and advised to boil water

before use

Case StudyRemediation Steps in Notice

• Repair of borehole head works• Empty & clean storage reservoir• Vermin proof reservoir outflow & pump house• Install lockable reservoir cover• written management procedure for disinfection

with record keeping• Regular inspection and cleaning of storage

tanks inside each dwelling

Case Study Borehole Head Works

Case Study storage reservoir protection (vermin proofing of outflow and pump house)

Conclusions• Most water suppliers [public supplies] have adopted water safety

planning as part of their water supply management operations [‘Business as Usual’ activities]

• Assessments under continuous review – new actions being identified on a rolling basis.

• Risks are being proactively identified and addressed – in many cases before DWI serves a Notice

• Actions are much less failure driven• WS planning is a continually developing process with quality and

content of risk assessment reports improving• DWI using risk assessment reports to focus its regulatory activities

i.e. To prioritise audits & inspections and event assessments• Risk assessments of private water supplies in infancy but already

seeing improvements to previously unsatisfactory situations

The importance of understanding how to do a water safety risk assessment !