MSc Dissertation 08 (Christopher Chua) - The Potential of the Uk Water Quality Regulatory Model for...

The Potential for Adapting the UK Water Quality Regulatory

Model for ASEAN Cities

- Further development of a unique Singapore

model and a study of technical example of

metaldehyde-containing pesticides in UK as an

illustration of regulatory issues in the UK

By

Christopher CHUA Wee Hong

A dissertation submitted in partial fulfilment of the requirements for the Degree of Masters of Science in Water

Regulations & Management

Centre for environmental Health Engineering (CEHE) Faculty of Engineering & Physical Sciences

University of Surrey

September 2008

© Christopher CHUA 2008

The Potential for Adapting the UK Water Quality Regulatory Model for ASEAN Cities

Christopher Chua

-ii- MSc in Water Regulation & Management

Dissertation 2008

Declaration of Originality

“I hereby declare that the dissertation entitled ‘The Potential for

Adapting the UK Water Quality Regulatory Model for ASEAN Cities’

for the partial fulfilment of the degree of MSc in Water Regulations &

Management, has been composed by myself and has not been presented or

accepted in any previous application for a degree. The work, of which this is a

record, has been carried out by myself unless otherwise stated and where the

work is mine, it reflects personal views and values. All quotations have been

distinguished by quotation marks and all sources of information have been

acknowledged by means of references including those of the Internet.”

…………………………………….

Christopher Chua Wee Hong

Date: ……………………………...


Christopher Chua

-iii- MSc in Water Regulation & Management

Dissertation 2008

Abstract

This dissertation considers the possibility of adapting the UK water

quality regulatory models for use in assisting ASEAN countries to develop

high levels of drinking water quality in their cities and surrounding rural

communities. The UK model could also potentially be modified by Singapore

in an innovative manner to further develop a unique water quality regulatory

model. Technology is available for ASEAN cities to provide safe drinking

water, but there is a concurrent need to develop the existing inadequate

regulatory framework to ensure a sustainable water supply.


Christopher Chua

-iv- MSc in Water Regulation & Management

Dissertation 2008

Acknowledgement

This dissertation is in fulfilment of the 1st MSc in Water Regulations &

Management and would not have been possible had it not been for:

God almighty for His blessings and guidance.

Classmates, staff, lecturers and visiting professors of the Centre of

Environmental Health Engineering (CEHE) at the University of Surrey (UniS),

especially Prof Barry Lloyd and my supervisor, Mr Brian Clarke, who has

provided lots of support and made water policies & issues discussions so

interesting and so enlightening. Special thanks to Ms Collette Laurens, who

provided the best administrative support and advice throughout the course.

The Drinking Water Inspectorate (DWI) for their support and for the

many inspectors who has provided support and lectured during the modules &

industrial attachment and for sharing their experiences, in particularly Prof.

Jenni Colbourne, Dr Jim Foster, Ms Sharon Evans, Dr Steve Lambert and Mr

Andy Taylor. Special thanks to Dr Annabelle May and Ms Allen Jane for their

help and advice.

Ms Jill Dryer from Severn Trent Water Limited for providing valued

advice and comments.

Dr Lee Tung Jean & Mr Ridzuan Ismail from the Water Services

Division of the Ministry of Environment & Water Resources (MEWR),

Singapore, for providing advice and experience sharing on the regulatory

situation in Singapore.

Colleagues from PUB, especially Mr Harry Seah, Mr Chong Hou Chun,

Mr Haja Nazarudeen, Mr Woo Chee Hoe, for their help and patience in

answering my queries. Special thanks to my Director, Mr Ng Han Tong, for

his help and his support.

Georgia, my supportive wife and my 2 girls, Natalie and Rebecca, for

being patient with me in not being able to bring them on more European

sightseeing tours and not spending more time playing during this period.


Christopher Chua

-v- MSc in Water Regulation & Management

Dissertation 2008

Acronyms and Abbreviations

ADB Asian Development Bank

ASEAN Association of South East Asian Nation

AWGWRM ASEAN Working Group on Water Resources Management

AWGESC ASEAN Working Group on Environmentally Sustainable Cities

BOD Biochemical Oxygen Demand

CIA Central Intelligence Agency, US

CCTV Close Circuit Television

COD Chemical Oxygen Demand

DALY Disability-adjusted life year

DBOO Design, Build Own & Operate

DBPs Disinfection by-products

DEFRA Department of Environment, Food and Rural Affairs, UK

DoH Department of Health

DWD Drinking Water Directive

DWU Drinking Water Unit, NEA, Singapore

DWI Drinking Water Inspectorate of England & Wales

DT50 Half-life of 50% of chemical after application to degrade

EA Environment Agency, UK

EEC European Economic Community

EPHA Environmental Public Health Act 1987, Singapore

EOI Expression of Intent

EU European Union

FAO Food & Agricultural Organisation, United Nations

FSA Food Safety Authority

GAC Granulated Activated Carbon

GCMS Gas Chromatography-Mass Spectrometry

HACCP Hazard Analysis and Critical Control Points

HPA Health Protection Agency, UK

IuWRM Integrated urban Water Resources Management

Koc Adsorption coefficient

Kow Octonol-water partition coefficient

LOAEL Lowest Observed Adverse Effect Level

MDG Millennium Development Goals

MGD Million Gallons per day


Christopher Chua

-vi- MSc in Water Regulation & Management

Dissertation 2008

MEWR Ministry of Environment & Water Resources, Singapore

NOAEL No Observed Adverse Effect Level

NEA National Environment Agency, Singapore

NEWater Singapore’s third national tap

Ofwat Water Services Regulation Authority

OECD Organisation for Economic Co-operation and Development

PCV Parameter Concentration Value

PSD Pesticide Safety Directorate

PUB PUB, Singapore’s National Water Agency

QMRA Qualitative Microbial Risk Assessment

RESCP Regional Environmental Sustainable Cities Programme

RO Reverse Osmosis membrane filtration

SIWW Singapore International Water Week

TAC Treaty of Amity and Cooperation in Southeast Asia

TDI Total daily Intake

TEU Treaty of European Union 1992

TOC Total Organic Carbon

TQM Total Quality Management

UK United Kingdom

UKAS United Kingdom Accredited Service

UKWIR United Kingdom Water Industry Research

UN United Nations

UNDP United Nations Development Programme

WHO World Health Organisation

WHOPES WHO Pesticide Evaluation Programme

WHOROE WHO Regional Office for Europe

WSD Water Studies Division, MEWR, Singapore

WSP Water Safety Plans

YLD Years of healthy life lost in states of less than full health

YLL Years of life lost by premature mortality


Christopher Chua

-vii- MSc in Water Regulation & Management

Dissertation 2008

Contents Page

Abstract ..................................................................................................................iii

Acknowledgement................................................................................................. iv

Acronyms and Abbreviations ................................................................................ v

Contents ................................................................................................................ vii

1. Introduction ................................................................................................- 1 -

2. Aims & Objectives ...................................................................................... - 2 -

3. Water Quality & Treatment ....................................................................... - 4 -

3.1. Water quality ........................................................................................ - 7 -

3.1.1. Microbiological water quality ................................................................ - 8 -

3.1.2. Chemical water quality ......................................................................... - 11 -

3.1.3. Acceptability water quality ................................................................... - 13 -

3.1.4. Radiological water quality ....................................................................- 14 -

3.2. Water treatment .................................................................................. - 15 -

4. Water Regulations ................................................................................... - 19 -

4.1. World Health Organisation................................................................- 19 -

4.1.1. Guidelines for safe drinking water ...................................................... - 20 -

4.1.2. Health- based targets ............................................................................- 21 -

4.1.3. Water Safety Plans ............................................................................... - 22 -

4.1.4. Surveillance .......................................................................................... - 27 -

4.1.5. Other Recommendations ..................................................................... - 29 -

4.2. European Union ..................................................................................- 31 -

4.2.1. Drinking Water Directives ................................................................... - 33 -

4.3. United Kingdom................................................................................. - 35 -

4.3.1. England & Wales .................................................................................. - 35 -

4.3.2. The Water Supply (Water Quality) Regulations 2000 ...................... - 38 -

4.3.3. The Drinking Water Inspectorate (DWI) ........................................... - 39 -

5. Metaldehyde-containing pesticide in the UK ........................................ - 50 -

5.1. Metaldehyde ....................................................................................... - 50 -

5.2. Role of Regulation ............................................................................. - 53 -

5.3. Case Study .......................................................................................... - 54 -


Christopher Chua

-viii- MSc in Water Regulation & Management

Dissertation 2008

Page

6. Water Situation in Southeast Asia .......................................................... - 57 -

6.1. Association of Southeast Asian Nations........................................... - 57 -

6.2. Singapore ............................................................................................ - 62 -

6.2.1. Water Quality Regulations .................................................................. - 64 -

6.2.2. Integrated Water Resources Management ......................................... - 68 -

7. Discussion ................................................................................................. - 74 -

7.1. International guidelines .................................................................... - 75 -

7.2. EU & ASEAN perspectives ................................................................ - 77 -

7.3. UK and Singapore water quality regulatory model ......................... - 78 -

7.4. Proposed ASEAN Water Quality Regulatory Model ....................... - 82 -

7.5. Metaldehyde-containing pesticides, a practical issue..................... - 86 -

8. Conclusion ................................................................................................ - 87 -

Appendix A - The UN Millennium Development Goals .............................. - 90 -

Appendix B – International Drinking Water Guidelines ............................ - 92 -

Appendix C – EU Drinking Water Regulations .......................................... - 104 -

Appendix D – Drinking Water Regulations in UK ...................................... - 114 -

Appendix E – The Environmental Public Health (Quality of Piped Drinking Water) Regulations 2008 ............................................................................. - 122 -

References ..................................................................................................... - 125 -


Christopher Chua

-ix- MSc in Water Regulation & Management

Dissertation 2008

List of Figures Page

FIGURE 1 OVERVIEW OF DISSERTATION .................................................................................... - 3 -

FIGURE 2. DISEASES CONTRIBUTING TO THE WATER-, SANITATION- & HYGIENE-RELATED DISEASE

BURDEN .................................................................................................................... - 5 -

FIGURE 3 ADVERSE HEALTH EFFECTS OF CHEMICAL AT CONCENTRATION .................................- 12 -

FIGURE 4 MEMBRANE PROCESS CHARACTERISTICS ................................................................. - 18 -

FIGURE 5 DEVELOPMENT OF THE WATER SAFETY PLANS ........................................................ - 25 -

FIGURE 6 PARTIES ACTIVE IN EU WATER POLICY PROCESS ...................................................... - 32 -

FIGURE 7 MAP OF UK ............................................................................................................. - 35 -

FIGURE 8 THE CURRENT UK WATER INDUSTRY ...................................................................... - 36 -

FIGURE 9 THE DRINKING WATER INDUSTRY IN ENGLAND & WALES ........................................ - 37 -

FIGURE 10 ORGANISATION OF THE DWI................................................................................... - 41 -

FIGURE 11 ASSESSMENT OF INCIDENTS FLOW DIAGRAM .......................................................... - 46 -

FIGURE 12 INFORMATION PROFILE OF METALDEHYDE. ............................................................ - 50 -

FIGURE 13 MAP OF ASEAN ...................................................................................................... - 57 -

FIGURE 14 ASEAN ORGANISATION STRUCTURE ....................................................................... - 58 -

FIGURE 15 ASEAN ENVIRONMENTAL GOVERNANCE STRUCTURE .............................................. - 59 -

FIGURE 16 MAP OF SINGAPORE ................................................................................................ - 62 -

FIGURE 17 CURRENT SINGAPORE WATER QUALITY REGULATORY MODEL .................................. - 65 -

FIGURE 18 CLOSING THE WATER LOOP IN SINGAPORE ............................................................. - 68 -

FIGURE 19 SINGAPORE'S CATCHMENT AREAS ............................................................................ - 70 -

FIGURE 20 PROPOSED BASIC WATER INDUSTRY MODEL ............................................................. - 83 -

List of Tables Page

TABLE 1 PARAMETERS USED IN ASSESSING WATER QUALITY IN DIFFERENT SITUATION .......... - 10 -

TABLE 2 CATEGORISATION OF SOURCE OF CHEMICAL CONSTITUENTS ..................................... - 11 -

TABLE 3 SUMMARY OF MAIN WATER TREATMENT PROCESSES ................................................ - 16 -

TABLE 4 EXAMPLES OF DEFINITION FOR LIKELIHOOD AND CONSEQUENCES OF A HAZARDOUS

EVENT ..................................................................................................................... - 24 -

TABLE 5 RISK MATRIX ........................................................................................................... - 24 -

TABLE 6 MINIMUM FAECAL INDICATOR TEST FREQUENCY IN DISTRIBUTION SYSTEMS ............ - 29 -

TABLE 7 MINIMUM SAMPLE FREQUENCY FOR PIPED SUPPLY .................................................. - 29 -

TABLE 8 TOXICITY STUDIES ON METALDEHYDE ...................................................................... - 51 -

TABLE 9 METALDEHYDE PROPERTIES TABLE ......................................................................... - 52 -

TABLE 10 WATER STATISTICS FOR SOUTHEAST ASIAN COUNTRIES (1995 & 2004) .................. - 60 -

TABLE 11 WATER RESOURCES STATISTICS FOR SINGAPORE ..................................................... - 69 -


Christopher Chua ‐ 1 ‐

MSc in Water Regulation & Management Dissertation 2008

1. Introduction

ASEAN cities are growing at a rapid pace, yet it seems that safe

drinking water is still a growing issue which needs to be addressed for the

protection of public health and for the country’s developments. While the

ASEAN member countries have access to available funding, technology and

skills necessary for the provision of water services, it seems that their

institutional arrangements and regulatory framework are inadequate to

support these developments.

Within ASEAN, Singapore has successfully implemented an integrated

water resources management strategy that allows its population to have access

to an uninterrupted supply of safe drinking water. However, Singapore has

just started to develop its water quality regulatory model to ensure sustainable

drinking water quality. The Ministry of Environment & Water Resources

(MEWR), together with its two operational statutory boards (National

Environment Agency (NEA) and PUB, Singapore’s national water agency), is

responsible for environment and water resources in Singapore. PUB is

responsible for water resources management, while NEA is responsible for

environmental and public health issues.

Most of the European Union (EU) member states are developed

countries with access to safe drinking water. The EU implements the Drinking

Water Directive (DWD) to ensure a common approach to the provision of

water services in the EU. In the UK, the water quality regulatory model is

unique with a privatised water industry in England & Wales. The Drinking

Water Inspectorate (DWI) is the independent water quality regulator which

has been successful in ensuring that England & Wales enjoy a high quality of

safe drinking water. It is highly likely that the effective UK water quality

regulatory model could be adapted to assist the ASEAN countries to develop

high levels of drinking water quality for its population. Singapore’s fledging

water quality regulatory model could also be refined by adopting some of the

experiences gained by the DWI in implementing the UK model.




2. Aims & Objectives

The focus of this dissertation is on the water quality regulatory models.

While there are other issues relating to regulating any water industry, such as

financial and environmental issues, these are beyond the scope of this

dissertation. Nevertheless, these issues need to be studied further to develop

a comprehensive model for the water industry.

This dissertation aims to:

• Analyse international drinking water quality guidelines, EU & UK

drinking water quality regulatory model;

• Assess water quality regulatory issues in the ASEAN member countries;

• Assess the water quality regulatory model in Singapore; and

• Assess issues relating to the metaldehyde-containing pesticide in the

UK as an example of a current issue in the regulatory system

The objectives of this dissertation are:

• Compare and contrast the regulatory approach in the UK and in

Singapore;

• Propose measures to enable Singapore to develop a unique water

quality regulatory model;

• Complete a detailed literature review, including DWI, MEWR, PUB &

NEA source materials;

• Develop a water quality regulatory model for the potential

improvement to safe drinking water in ASEAN cities and

• Complete a detailed study of issues and information relating to

metaldehyde-containing pesticide in the UK

The overview of the dissertation is shown in Figure 1.




Figure 1 Overview of dissertation

Water Quality

International United Nations

• Millennium Development Goals

WHO • Guidelines

Regional European Union

• Organisation • DWD framework • Directives & Regulations

National United Kingdom

• Regulations • Regulators (DWI)

Association of Southeast Asian Nations ASEAN

• Organisation • Approach to issues • Water Quality guidelines and objectives

Rural Communities Urban Cities

Singapore • Integrated Water Resources Management • Statutory Authorities & Water Suppliers • Current Regulations

Metaldehyde-containing pesticide • Metaldehyde • Role of regulations • Case study

Discussion & Conclusion • Review of the WHO guidelines • Comparison of the regulatory approach in UK & Singapore • Proposed ASEAN Water quality regulatory model • Proposed development of the Singapore water quality regulatory model




3. Water Quality & Treatment

World leaders of the 189 United Nation (UN) member states, at the

United Nations Millennium Summit held in New York on 6 - 8 September

2000, agreed to a common goal of the United Nations Millennium Declaration

to work together on global social issues and to ensure that the benefits of

globalisation be inclusive and equitable to all people, especially for those in

the developing countries or economies (UN, 2000)1.

This declaration led to the development of the time bound and

measurable Millennium Development Goals (MDG) which provides a

framework for global action towards a common goal. The MDGs, comprising

of 8 goals and 18 targets, are listed in Appendix A. The relevant target and

goal related to water and sanitation are Goal 7 and target 10, which states,

“Goal 7: Ensure environmental sustainability

Target 10: Halve, by 2015, the proportion of people without

sustainable access to safe drinking water and basic sanitation.”

(Lenten R. et al, UNDP, 2005)2

At the opening of the water exhibition organized by the American

Museum of Natural History and the UN Department of Public Information in

Oct 07, UN Secretary-General Ban Ki-moon said that “Safe drinking water and

adequate sanitation are crucial for poverty reduction, crucial for sustainable

development, and crucial for achieving any and every one of the Millennium

Development Goals.” Mr Ban also noted that high population growth,

unsustainable consumption patterns, poor management practices, pollution,

inadequate investment in infrastructure, and low efficiency in water-use are

putting huge stresses on the earth’s water resources and estimates that the

current 700 million people in 43 countries affected by water scarcity could

swell to more than 3 billion by 2025 (UN News centre, 24 Oct 2007)3.

The World Health Organisation (WHO) (2008) 4 affirms that “the

combination of safe drinking water and hygienic sanitation facilities is a

precondition for success in the fight against poverty and hunger (Goal 1),

primary education (Goal 2), gender equality and women empowerment (Goal




3), child mortality (Goal 4), maternal health (Goal 5), HIV/AIDS and Malaria

(Goal 6), ensure environmental sustainability (Goal 7) and develop global

partnerships (Goal 8).”

Prüss-Üstün A. et al (2008)5 wrote that at least 10% of the world’s

disease burden (in disability-adjusted life years or DALYs, a weighted measure

of deaths and disability) could be alleviated by improvement in drinking water,

sanitation, hygiene and water resources management and these only include

those diseases which are quantifiable or have adequate evidence. The

proportion of diseases contributing to this disease burden is shown in Figure

2. Drinking water quality and access improvements are mainly related to the

reduction of diarrhoeal diseases, malnutrition and Trachoma.

Figure 2 Diseases contributing to the water-, sanitation- & hygiene-related disease burden

(Prüss-Üstün A. et al, pp 11, 2008)5

Prüss-Üstün A. et al (2008)5 further concluded from a systematic

review of diarrhoeal disease literature, that improvement in water supply and

water quality would reduce the frequency of diarrhoeal diseases by 25% and 31%

respectively.

The WHO (2006)7 uses Disability-Adjusted Life Years (DALY) as the

common measurement to objectively evaluate and compare the effects of the




diverse hazards associated with very adverse health outcomes and is defined

as the weighted sum of years of life lost by premature mortality (YLL) and

years of life lived in disability (YLD) or DALY = YLL + YLD. Each health

effect is weighted for its severity from 0 (normal good health) to 1 (death) and

multiplied by time duration and the number of people affected. DALYs are

used to compare health effects of different agents in water. The Guidelines’

reference level of risk is 10-6 DALYs per person-year.

A major concern of water supply is the spread of the infectious water-

related diseases through the water supply. This refers to diseases caused by

living organisms (bacteria, viruses or parasites like protozoa or helminths)

which are usually spread from person to another, or to or from animal, and is

related to water. Cairncross S. & Feachem R. (1993)6 classified these diseases

by their distinct route of transmission through water:

a) Water-borne route – transmission occurs when pathogens in water

is drunk by a person or animal;

b) Water-washed route – transmission is reduced when there is

sufficient quantity of water for hygiene purposes;

c) Water-based route – transmission is due to infection by pathogens

which spend part of its life cycle in water; and

d) Insect-vector route – transmission is spread by insects which either

breed in water or bite near water.

Cairncross S. & Feachem R. (1993)6 further recommended that water-

borne and water-washed diseases could be prevented with an improvement in

quality and sufficiency of safe drinking water supply and using this supply

rather than an unsafe source.

This underlies the importance of water and sanitation for any

sustainable developments in a country. Evidence exists to support the need

for improvements in drinking water, but there are still questions in

determining what it actually means to have adequate access to water of a

suitable water quality. What would be a safe concentration of any parameter,

such that it is considered safe?




3.1. Water quality

The WHO Guidelines for Drinking Water Quality (WHO, 2006) 7

defines safe drinking water as water of a certain microbiological, chemical,

physical and radiological quality that does not represent any significant health

risk over a lifetime of consumption. In the 3rd edition of the WHO Guidelines,

the WHO has moved away from setting an international standard for drinking

water quality to a risk-based approach for setting national or regional

standards and regulations. The WHO framework for safe drinking water is

covered in Chapter 4.1.1.

As the setting of water quality standards depends on the local context

and conditions, the WHO recommends a preventive rather than remedial

approach to the management of water supplies. There is still a need then to

monitor at sufficient frequency and ensure that the final water quality meets

certain water quality standards. Water quality standards should be scientific

& evidence based and must be determined by local authorities based on

international guidelines, regional recommendations and national

requirements.

The WHO (2006)7 advises that national regulatory agency and local

water authorities determine and respond to the constituents of public health

significance, as under any given circumstances, only a few constituents are of

concern.

The WHO (2006)7 guidelines assumes a per capita consumption of 1

litre of unboiled water for microbial hazards and for chemical hazards, the

daily per capita consumption of 2 litres by a person weighing 60kg.




3.1.1. Microbiological water quality

The WHO (2006)7 considers the control of outbreaks of water borne

diseases as the foremost priority in drinking water quality control. This is

because such infectious outbreaks could affect a large number of people in a

short period of time. The public health burden of the diverse pathogen-

causing infectious diseases depends on the severity, infectivity and exposed

population size.

Cairncross S. & Feachem R. (1993)6 highlighted that all faecal-oral

diseases and most of the water based diseases are caused by pathogens

transmitted in human excreta, normally in faeces. Cairncross S. & Feachem R.

(1993)6 also explained that as many of the pathogens are present in very small

number in polluted water, it is therefore common practice to detect “indicator

bacteria” instead.

Lloyd (2007)8 noted that Thermotolerant coliform and Escherichia coli

met 7 (bold) out of the following 11 criteria for the ideal water industry

indicator of the presence of enteric-pathogens:

- Presence of indicator denote the presence of all relevant pathogens;

- Detectable whenever a waterborne pathogen is present

- Present in greater number than the pathogens

- Absent when the pathogens are absent

- Abundant in human and animal excreta and absent from

other sources

- Unable to grow in water

- Survive longer than pathogens in water

- More resistant than pathogens to disinfectants

- Rapidly and reliably isolated

- Easily identified.

- Precisely enumerated.

The WHO (2006)7 recognised that these 2 indicator bacteria are

important parameters for verification of microbial quality and recommends

that E. coli or Thermotolerant coliform must not be detectable in a 100-ml




sample of treated potable water. The guidelines for microbiological quality for

drinking water are found in Appendix B-1.

While indicator bacteria tests provide a quick overview of the possible

health risk due to faecal contamination, it does not allow the detection of

some pathogenic viruses and protozoan like Cryptosporidium or Giardia.

OECD & WHO (2003) 9 explained that this is because the viruses and protozoa

have different environmental behaviour and survival characteristics compared

to faecal bacteria. There is no single indicator organism that can be

universally used for all purposes in surveillance, as each has its own

advantages and disadvantages. Therefore, there might be a need for direct

pathogen testing, which is still in a developmental stage and requires a highly

specialised laboratory, highly trained staff, appropriate safety measures and

time.

OECD & WHO (2003)9 discussed some of the possible microbiological

alternative and non-microbial parameters which could be used to assess

microbial water quality in different situations. This is summarised in Table 1.

It is noted that all the parameters, except for Pseudomonas and Aeromonas

spp. are suitable parameters in outbreak investigations. A more detailed

explanation of the parameters is found in Appendix B-2.

The WHO (2006)7 thus recommends a qualitative microbial risk

assessment (QMRA), epidemiological studies and case histories of outbreaks

to determine the necessary microbial water quality improvements needed.

This takes into account the following:

• Hazard identification – identifying all potential hazardous events such

as the source(s) and possible time of occurrence and the selection and

control of possible representative organism to ensure the control of all

pathogens of concern.

• Exposure assessment – subjective estimation of the concentration of

pathogenic microbes ingested and the volume of water consumed

(treated and/or unboiled) by exposed individuals;




• Dose-response assessment – study of dose-response of healthy

volunteer to derive the probability of adverse health effect after

exposure to pathogenic organisms and to determine the infective dose;

• Risk characterisation - integration of all available information from

exposure, dose-response, severity and risk of infection to determine the

disease burden of each potential disease in DALYs.

Table 1 Parameters used in assessing water quality in different situation

Sanitary survey,

Source-water &

groundwater

characterization

Treatment

removal

efficiency

Disinfection

efficiency

Treated water Ingress in

Distribution

system

Regrowth in

distribution

system

Enteric viruses Total coliforms Total coliforms Total coliforms Total coliforms

Thermotolerant

coliforms

Thermotolerant

coliforms

Thermotolerant

coliforms

Thermotolerant

coliforms

Thermotolerant

coliforms

Thermotolerant

coliforms

Escherichia coli Escherichia coli Escherichia coli Escherichia coli Escherichia coli

Faecal streptococci

(enterococci)*

Total bacteria

(microscopic)

Total bacteria

(microscopic)

Total bacteria

(microscopic)

Total bacteria

(microscopic)

Somatic coliphages Viable bacteria

(microscopic)

Viable bacteria

(microscopic)

Viable bacteria

(microscopic)

Viable bacteria

(microscopic)

F specific RNA

phages

Heterotrophic

bacteria

Heterotrophic

bacteria

Heterotrophic

bacteria

Heterotrophic

bacteria

Bacteroides phages Aerobic spore-

forming bacteria

Aerobic spore-

forming bacteria

Pseudomonas,

Aeromonas

Clostridium

perfringens

Clostridium

perfringens

Somatic

coliphages

Giardia cysts,

Cryptosporidium

oocysts

Giardia cysts,

Cryptosporidiu

m oocysts

F specific RNA

phages

Rainfall events* Particle size

analysis

Bacteroides

phages

Flow * Turbidity Flow Flow Flow

Solids (Total and

dissolved)

pH Colour

Conductivity Disinfectant

residual

Disinfectant

residual

Disinfectant

residual

Turbidity

Organic matter

(TOC, BOD, COD)

Organic matter

(TOC, BOD, COD)

Microscopic

particulate analysis

Ammonia

* faecal streptococci and flow parameter are for sanitary survey and surface water characterisation only, while rainfall is

only used for sanitary survey and microscopic particulate analysis is meant for groundwater characterisation.




3.1.2. Chemical water quality

Natural occurring or pollution derived chemicals are found in varying

quantities in water and can be a significant contribution to public health

problems. The chemicals can be grouped according to their original source as

shown in Table 2. The adverse health effects of most chemical contaminants

are associated with long-term exposure. Thomson T. et al (2007) 10

recommended that it is more effective to identify and focus on priority

chemicals of concern, as assessing and developing strategies for every

chemical would be impractical and require plenty of resources.

Table 2 Categorisation of source of chemical constituents

Source of Chemical constituents Example of sources

Naturally occurring (including

naturally occurring algal toxins)

Rocks, soils, cyanobacteria in eutrophic

lakes

Agricultural activities Manures, fertilizers, pesticides, intensive

animal practices

Human settlements Sewerage & waste disposal, urban runoff,

fuel leakage,

Industrial activities Mining, manufacturing, processing,

Water treatment or materials in

contact with water

Water treatment chemicals, disinfection

by-products (DBPs), storage tank/pipes

material corrosion and leeching

(Thomson T. et al, 2007)10

The WHO guidelines for drinking water quality (2008) 11 provide

guideline values for “36 inorganic constituents, 27 industrial chemicals, 36

pesticides, 4 disinfectants and 23 disinfectant-by-products”, of which the 95

chemicals of health significance in drinking water are found in Appendix B-1.

These chemicals are chosen based on the following criteria:

• Credible evidence of chemicals occurring in drinking water together

with evidence of actual or potential toxicity;

• Significant international concern; or

• Considered for inclusion or is included in the WHO Pesticide

Evaluation Scheme (WHOPES) programme




The derivation of these guideline values are scientifically based on

health effect studies on human populations or toxicity studies on laboratory

animals, supported by other appropriate studies. Health effects studies on

human population are preferred, but there is limited value on such studies

because of the lack of qualitative information on the concentration to which

people have been exposed to and due to simultaneous exposure to other

agents. There is uncertainty in the findings from the more frequently used

toxicity studies on laboratory animals because of the relatively small number

of animals used and relatively high dose administered. This requires

extrapolating the results from animals to humans as the human populations

are usually exposed to low doses (WHO, 2006)7. This means that most

guideline values are likely to be very conservative.

As illustrated in Figure 3, different approaches are taken for the

different groups of chemicals:

• Carcinogens – non-threshold chemicals, where there are adverse health

effects at any level of concentration and no safe dose;

• Toxic substances – threshold chemicals, where there are no adverse

health effects below a certain concentration;

• Essential elements – necessary for humans and animals for normal

functions, for which there is a safe concentration range, where adverse

health effects are observed from deficiency (below safe concentration

range) and over-exposure (above concentration range).

Figure 3 Adverse health effects of chemical at concentration

NOAEL

Adverse health effects

Concentration (mg/l) Safe concentration range

Carcinogenic substances (Arsenic, Vinyl Chloride)

Toxic substances (Boron, Cyanide, Lead)

Essential elements (fluoride, selenium, iodine, manganese, copper)




For threshold chemicals, there is a need to derive the Tolerable Daily

Intake (TDI), which is defined as amount of substances in food and drinking

water, expressed on a body weight basis (mg/kg of body weight), that can be

consumed over a lifetime without appreciable health risk. The guidelines

values are derived as follows:

Where

NOAEL = No Observed Adverse Effect Levels

LOAEL = Lowest Observed Adverse Effect Level*

UF = Uncertainty factor

bw = body weight

P = fraction of TDI allocated to drinking water

C = daily drinking-water consumption

* If LOAEL is used, an additional uncertainty factor has to be applied

(WHO, 2006) 7

3.1.3. Acceptability water quality

Drinking water must not only be safe, but it must be acceptable to

consumers. While most consumers are not able to determine the safety of

their drinking water due to lack of equipments, they could reject the water due

to its physical appearance, taste and odour and use an alternate unsafe source.

The physical appearance, taste and odour of drinking water are affected

by microbiological and chemical contaminants in water (attached as

Appendix B-3), but the acceptability of drinking water by consumers is also

subjective and influenced by individual and local factors. As most of these

contaminants have microbiological and chemical health-based guidelines, the

parameters that fall into this category would include colour, pH, turbidity,

hardness and total dissolved solids. (WHO, 2006)7




3.1.4. Radiological water quality

The WHO (2006)7 stated that the long-term incidence of cancer in

humans and animals could increase as a result of low to moderate dose of

radiation exposure. Radiation arises from naturally-occurring and man-made

sources.

The guideline value is the recommended reference dose level equivalent

to a cumulative 0.1mSv in annual drinking water consumption, given as

activity concentration (Bq/l). The WHO (2006)7 states that “The SI unit for

radioactivity is the Becquerel (Bq), where 1Bq = 1 disintegration per

second...The SI unit for equivalent and effective dose is the sievert (Sv) where

1Sv = 1 J/kg”. (WHO, 2007)7

The guidance levels for radionuclide in drinking water are attached as

Appendix B-1 and is calculated by

.

Where

GL = guidance level of radionuclide in drinking water (Bq/litre)

IDC = individual dose criterion, equal to 0.1mSv/yr for this calculation

Hing = dose coefficient for ingestion by adults (mSv/Bq)

q = annual ingested volume of drinking water, assumed to be 730l/yr

As the concentration of radionuclide in drinking water is relatively low,

the WHO (2006)7 recommends that it might not be justified to identify

individual radioactive species using sophisticated and expensive analysis

without first carrying out a screening procedure for detection limits of 0.5

Bq/litre for gross alpha activity and 1 Bq/litre for gross beta activity.

(WHO, 2007)7




3.2. Water treatment

It is common to treat raw water to produce safe drinking water for the

protection of public health, as most raw water quality does not meet safe

drinking water standards. Allan S.C. (1997)12 cited that there are eight specific

reasons for treatment water:

• To remove disease-causing pathogens;

• To remove potentially toxic natural or synthetic substances;

• To remove dissolved and gaseous radioactivity;

• To improve organoleptic quality of water to prevent consumer rejecting

water due to its physical appearance, taste or odour;

• To prevent bacterial after-growth in the distribution system;

• To prevent deposition and silting up of pipes;

• To prevent corrosion and dissolution of pipes and fittings; and

• To comply with local, national and international law on water quality.

Water treatment is based on a multi-barrier approach to removing

contaminants and depends, amongst other things, on the quality of the source

water and final water quality desired. The conventional approach is to choose

a combination of the appropriate processes at the treatment works. Some of

the main treatment processes can be found in Table 3. Typical water

treatment processes usually comprises of pre-treatment, main treatment and

disinfection.




Table 3 Summary of main water treatment processes Processes Functions

Screens Sets of coarse (100mm spacing) to fine screens used as a physical removal of larger particles such as litters or branches and for protection of downstream processes

Roughening filters

Coarse media (rock or gravel with size 4 – 12mm) pre-filter used to reduce turbidity (60-90% removal) and faecal coliform bacteria (93 – 99.5% removal)

Micro-strainers Stainless steel or polyester wire fabric mesh of apertures 15 – 45mm pre-treatment strainers for removing 40-70% algae cells and large protozoa and 5-20% turbidity removal.

Aeration The use of a cascade or fountain system to introduce air into the raw water to increase dissolved oxygen in water to protect downstream processes, reduce CO2, raise pH, remove iron and manganese from water and improve taste in water by stripping out hydrogen sulphide and volatile organic compounds.

Off-stream/ bank side storage

Self-purification reservoir storage to improve water quality before treatment and to ensure adequate supplies at periods of peak demand. Storage also eliminates variation in water quality due to floods and surface run-offs. Exposure to sunlight (natural UV radiation) kills some pathogens and removes colour. Long term storage allows suspended solids to settle and reduces turbidity, while algae can remove hardness by converting bicarbonates to precipitate carbonates.

Coagulation & flocculation

Chemical coagulant like alum (aluminium sulphate) or other salts of aluminium or iron are added and rapidly mixed to allow colloidal particles in the water to coagulate and then agitated to flocculate so that the flocs can be removed more easily later. The efficiency of the process depends on the raw water quality, coagulant dose, coagulant aid, mixing conditions and pH. Jar tests are usually carried out to determine the optimum dose required. Optimal coagulation can carry out 1-2 log removal of bacteria, viruses and protozoa, as well as removing turbidity, suspended solids, certain heavy metals and low-solubility organochlorine pesticides.

Sedimentation Solid-liquid separation process to remove the solids from the raw water by allowing the flocs to settle.

Dissolved Air-flotation (DAF)

DAF functions like a sedimentation tank to remove flocs, except that air bubbles are introduced from the bottom of the tank to allow the floc particles to attach to the air bubbles and float to the surface, where it can be skimmed off. DAF is found to be effective in the removal of algal cells, Cryptosporidium oocysts or humic acids.

Lime softening The addition of lime or soda ash to increase the pH of water to reduce hardness by precipitating calcium and magnesium from the raw water. Lime softening can also aid in the removal of bacteria (2 log removal maximum), viruses (up to 4 log removal) and protozoa (up to 2 log removal) at high pH (>11) depending on temperature, time of exposure and pH.

Ion Exchange The adsorption processes where there is a reversible interchange of same charge ions between a solid ion-exchange medium and the raw water. With different resins used, ion exchange can be used for water softening and for removal of radionuclide and heavy metals, nitrate, arsenic, cadmium, selenium, uranium and dissolved organic carbon.

Rapid gravity filtration

The use of single, dual- or multi-media of granular material like sand or anthracite of different grades to allow water to pass rapidly through the relatively large gaps in between the grains to remove the suspended solids




Processes Functions through straining, adsorption, adhesion and sedimentation. Filtration rates are typically 5 – 10 m/h. rapid gravity filtration can also remove turbidity, adsorbed chemicals, oxidised iron and manganese from raw water. Under optimum coagulation conditions, up to 2 log removal of bacteria, viruses and protozoa can be achieved.

Pressure filters The rapid gravity filter process is carried out in an enclosed in an enclosed cylindrical shell to eliminate the need for a separate pumping stage.

Slow Sand Filtration

A non-pressurised, chemical-free biological filtration process where the raw water is passed through 0.15-0.3mm diameter fine sand of 0.5m to 1.5m depth and a flow rate of 0.1 to 0.3 m3/m2.h. There is a thin biological active filter skin at the top called the Schmutzdecke. A matured slow sand filter can remove biological particles such as bacteria, viruses, Cryptosporidium, faecal coliform and other organic debris up to 4-log removal, iron and manganese biologically and is effective for the removal of algae and organics, including certain pesticides and ammonia.

Membrane – Microfiltration (MF)

Physical pressure-driven filtration process to remove contaminants from water using a semi-porous membrane media of pore size of 0.01-12µm at operating pressure of 1 -2 bars. Microfiltration can remove algae, protozoa, bacteria and microbes larger than 0.2 micron and is widely used to remove chlorine resistant pathogens like Cryptosporidium oocysts and Giardia

cysts. Please see Figure 4. Membrane filtration – ultrafiltration (UF)

Similar to MF except that pore size is in the range of 1nm – 100nm. UF operates at less than 5bars and is capable of removing suspended solids (turbidity <0.1 NTU), organics (molecular cut-off weight of 800), bacteria and viruses, including Cryptosporidium (at least 4 log removal). Please see

Figure 4. Membrane filtration – nanofiltration (NF)

Similar to UF, except pore size is in the range of 0.001mm to 0.01mm. NF operates at about 5 bars and rejects divalent ions (magnesium and calcium), organics (molecular cut-off weight above 200), suspended solids, bacteria and viruses. Please see Figure 4.

Membrane filtration - reverse osmosis (RO)

Similar to NF, except pore size is less than 0.002mm. Operating at 15- 50 bar, only water essentially passes through, while dissolved salts, suspended monovalent ions and organics (molecular cut-off weight above 50). Complete removal of bacteria, viruses and protozoa is possible with pre-treatment and membrane integrity conserved. Please see Figure 4.

Activated carbon adsorption

Normally in powdered (PAC) or granular (GAC) form using porous carbonaceous material with large surface area (500-1500 m2/g) for the removal of removal of pesticides and other organic chemicals, cyanobacterial toxins, total organic carbon and for control of taste and odour.

Chlorine disinfection

Chlorine is commonly used in destroying or inactivating most water-borne disease-causing micro-organisms, and as a powerful oxidant to improve water quality by removing reduced nitrogen, iron, manganese, sulphide and certain organic species. Chlorine can combine with ammonia to form chlorine residual (chloramines) to provide protection against recontamination in the distribution network. Chlorine, chlorine dioxide or chloramines can be used.

Ozone disinfection

As a powerful oxidant, ozone is used as a primary disinfectant to effectively inactivate harmful protozoan that form cysts and almost all other pathogens. Ozone is also effective in removing some pesticides and organic materials.




Processes Functions Ultra-violet (UV) disinfection

The adsorption of UV radiation with a frequency of 250 – 256 nm in their DNA can inactivate microorganisms. A quick, chemical-free process, UV is able to remove bacteria up to 8 log removal; viruses up to 6 log removal and protozoa like Cryptosporidium oocysts by a 4 log removal depending on dosing.

Plumb solvency reduction

Small quantities of phosphate can be added to reduce lead in pipe dissolving in treated water.

(Wikipedia, 2008)13 (WHO, 2006)7 (WHO & OECD, 2003)9 (Koch membrane, 2008)14 (Gray N.F., 2005)15

Figure 4 Membrane process characteristics (Koch membrane, 2008)14




4. Water Regulations

The purpose of drinking water regulations is to ensure that the

consumers have safe potable water through effective control. Legislation need

to:

• Define clearly the roles and responsibility of the stakeholders (water

supplier, policy and regulatory authorities, public health authorities,

consumers, chemical and material suppliers, analytical services

providers, etc) involved in drinking water supply;

• Have sufficient enforcement measures;

• Allows for changes and amendments needed for future conditions; and

• Be flexible enough to cater to different situations.

(WHO, 2006)7

The UNDP (2008)16 recognises that the lack of access to safe drinking

water results mainly from profound failure in water governance. Water

governance requires an integrated political, social, economic and

administrative system to manage water resources and provide water services

to the population.

To gain a better understanding of drinking water regulations, it is

useful to look at the international guidelines from the WHO, the regional

directives of the EU and the national regulations of the UK.

4.1. World Health Organisation

The WHO was established in 1948 with the aim of attaining the highest

possible levels of health for all people in all countries. Representatives of the

193 WHO member states and 2 associate members form the WHO Assembly,

which sets policies, approves budget and appoints the Director-General for a

5-year term. The WHO Assembly also elects the 34 member Executive Board.

Six regional committees focus on regional health matters. The WHO

constitution comprises of 82 articles which details the operations and

functions of the WHO. (WHO, 2006)17 (WHO, 2008)18




The WHO published international drinking water standards in 1958,

1963 and 1971. These are superseded by the WHO guidelines for drinking

water quality, published in 3 volumes. The 1st edition and 2nd edition were

published in 1983-84 and 1993-97 respectively. (WHO, 2008)18

The 3rd edition of volume 1 of the Guidelines, a rolling edition, was

published in 2004 and the 1st addendum was added in 2006. Parts of the

previous Volume 2 are replaced by a series of publications providing

information on the assessment and management of risks associated with

microbial hazards and by internationally peer-reviewed risk assessments for

specific chemicals, while the previous volume 3 is still valid in providing

guidance on good practices in surveillance, monitoring and assessment of

drinking water quality in community supplies. (WHO, 2008)18

The 4th edition for Volume 1 of the Guidelines is currently in progress

(Davidson A. et al, 2005)19 (WHO, 2008)20. More than 20 WHO water quality

experts last met in Singapore to review the technical work for the 4th edition

on 24-27 Jun 08. This was held in conjunction with the Singapore

International Water Week (SIWW, 2008)21.

The WHO guidelines for safe drinking water are commonly used as the

reference source and form the basis of water quality standards for most

countries in the world. The guideline values for water quality parameters are

found in Appendix B-1.

4.1.1. Guidelines for safe drinking water

The Guidelines for drinking water quality (WHO, 2006)7 outline a

framework to ensure that safe drinking water could be provided as part of the

strategy for the protection of public health and the reduction of water-related

diseases. The idea is to critically analyse any drinking water system from

catchment to tap for hazards control and prevention.




The framework comprises of the following:

• Health-based targets based on national and local conditions for the

purpose of protecting and improving public health;

• Water safety plans for a systematic multi-barrier approach to a

comprehensive risk analysis and management of water supply; and

• Surveillance to monitor and verify on the compliance with the water

safety plan and ensure the adequacy of supply for public health.

(WHO, 2006)7

4.1.2. Health- based targets

Health-based targets set the health and water quality goals for the

implementation of the safe drinking water framework to ensure realistic

targets for the effective protection of overall public health in the local context.

Every country and community will have different and unique levels of health-

based targets, as there is a need to take into account the status, trends,

contribution of drinking water to the transmission of infectious diseases and

to overall exposure to hazardous chemicals both in individual and overall

public health management, access to water, local situations (including

economic, environmental, social and cultural conditions) and local (financial,

technical and institutional) resources. (WHO, 2006)7

The 4 principal types of health-based targets include:

• Health outcome targets based on the reduction in the total disease

burden for a particular microbial or chemical hazards largely

attributable to water;

• Water quality targets for mainly chemical constituents, additives

or treatment by-products in water with stable concentrations that

represent health risks from long term exposure, typically expressed as

guideline values;

• Performance targets for control of constituents with fluctuations in

numbers or short periods that represent health risks in short term

exposure, typically expressed as required reductions; and




• Specified technology targets for specific equipment or processes

or actions for smaller municipal, community and household drinking

water supplies, which typically include recommendations and guidance

for application and operation of such technology.

(WHO, 2006)7

The proportion of exposure to enteric pathogens or hazardous

chemicals attributed to drinking water needs to be considered, as there could

be other sources of exposure.

4.1.3. Water Safety Plans

The Water Safety Plan draws upon the multi-barrier approach and the

Hazard Analysis and Critical Control Point (HACCP) methodology used

extensively in the food industry, as well as approaches found in the quality

assurance standards management systems like ISO 9000 and total quality

management (TQM) (Godfrey S. & Howard G., 2004)22. Drury D. (2007)23

highlighted that the WSPs analyse quality assurance within the operations &

procedures and do not depend on end-point quality assessments.

The 3 components of the WSP are:

• System assessment of the entire drinking water supply chain from

catchment to tap, as a whole, can achieve the water quality as specified

in the health-based targets. The assessment identifies potential

hazards for each part of the supply chain, its individual level of risks

and the appropriate control measures;

• Operational monitoring of the rapid identification of deviation of

the required performances of each control measure for the hazards in

the systems; and

• Management plans to document the system assessment, normal

and incident operations, monitoring, validation, remedial actions,

reporting and communication procedures and supporting programmes.

(WHO, 2006)7




DWI (2005)24 highlighted that the team responsible for developing the

water safety plans requires:

• Complete in-depth knowledge of each element of the specific water

supply chain and its capability to supply safe water which meets the

health-based standards and requirements;

• Identification of the hazards for each element of the water supply chain,

the consequences and frequency of occurrence of each hazard and the

level of risk each of these presents;

• Identification and validation of the short-term, medium-term and long-

term control measures to reduce each identified risk to an acceptable

level;

• Implementation of a routine monitoring system of those control

measures with action trigger criteria when the control measures are not

within the specified targets;

• Implementation of remedial action plans when a control measure is

outside of the specified target with checks to certify that the system is

brought back under control;

• Validation monitoring to determine whether the system is performing

as assumed in the system assessment; and

• Independent verification for the correct implementation of the WSP to

ensure that the water supplied is safe and meets health-based and other

regulatory targets.

The water safety plan team looks critically at the entire water system

and their individual components (from catchment, intake, each treatment

process, distribution, to the customer’s tap) to identify what the risk of every

possible hazard is, how to reduce and control the risk of the hazards and how

to show that the controls are working. Drury D. (2007)23 explains that the

development of a successful WSP requires the involvement and participation

by company staff members who have a deep understanding on how the

company operates each component of the water supply systems.




A hazardous event is an incident or situation that can lead to the

presence of a hazard, which is anything that could cause harm. There is a

need to determine the risk of every hazardous event. Risk is defined as the

combination of the likelihood of a hazardous event occurring and the

consequences of the hazard. The definition of the likelihood and

consequences of an event, with examples in bracket, are shown in Table 4.

Table 4 Examples of definition for likelihood and consequences of a hazardous event

Likelihood of a hazardous event occurring

Severity of the Consequences of a hazardous event if it occur

A Almost certain (Once a day) 1 Insignificant (No significant impact)

B Likely (Once a week) 2 Minor (minor impact to a small population)

C Moderate (Once a month) 3 Moderate (minor impact to a large population)

D Unlikely (Once a year) 4 Major (major impact to a small population)

E Rare (Once every 5 years) 5 Catastrophic (major impact to a large population)

Risk prioritisation can then be carried out using a matrix as shown in

Table 5 to identify the significance of the hazard, the importance of each

hazard and the prioritisation of improvements needed. For example, an

insignificant hazard that is almost certain to occur will be ranked as a medium

risk event, while a catastrophic hazard which is unlikely to occur will be

ranked as a high risk event.

Table 5 Risk matrix Consequences

Likelihood 1 2 3 4 5

A (Almost certain ) V High

B (Likely)

C (Moderate) Medium High

D(unlikely) Low

E (rare) Negligible

(WHO, 2005)25




The steps taken to develop a WSP are illustrated clearly in Figure 5

(WHO, 2005)25.

(WHO, 2005)25

A multi-disciplinary team of experts with a thorough understanding of

the individual elements of the water system needs to be assembled to develop

the WSP. The team should consist of specialists with knowledge of the

catchment and raw water sources, treatment processes, distribution networks,

drinking water quality, public health, domestic distribution system and

customer matters. Senior management support is crucial in the development

of the WSP. A team leader with sufficient authority, interpersonal and

organisation skill should be selected to drive the project and ensure focus.

Figure 5 Development of the Water Safety Plans

Assemble the WSP Team

Document and describe the system

Carry out a hazard assessment and risk characterisation

Identify control measures

Define operational limits and monitoring of control measures

Establish verification procedures

Establish management procedures for corrective actions, normal

operations and incident response

Establish record keeping

Validation and verification

Review experience and future

needs

Review, approval and

audit

Supporting programmes

System assessm

ent

Op

erational

mon

itoring

Man

agemen

t &

Com

mu

nication

s




The role of each individual member should be defined properly.

Communication procedures with all stakeholders should also be established.

Next, the team should collect and evaluate information to document

and describe the entire water supply system. If information is missing, then

there is a need to determine how and where to collect the information. A

detailed flow diagram will be helpful in providing an overview. Stakeholders

and users are also identified.

For each element of the water supply system, the team should identify

potential failures, problems, their locations and implications in terms of

hazards and hazardous events. The team should also consider influencing

factors. This involves assessment of historic information and events as well as

predictive information based on expert knowledge. Next, the WSP team

should determine the consequence and likelihood of each hazardous event and

the need for action. This is usually done using the risk scoring matrix.

Concurrently with the identification of hazards and evaluation of risk,

the WSP team should document existing and potential control measures and

decide if these control measures are effective. There is also a need to

determine if the control measures could introduce or affect any other

hazard/risk and their subsequent control measures, if necessary. Risk of the

hazardous events should be reprioritised after the control measures are put in

place.

At the same time, if there are insufficient control measures or the risks

are not sufficiently reduced or mitigated, then the team should develop a

short-term, medium-term and long-term action and improvement plan to

mitigate or control each significant risk.

Following the identification of all hazardous events, their hazards,

associated risk and control measures, the WSP team will need to define

operational limits of all critical control points to monitor the control measures

and actions that need to be taken if there is a deviation. This ensures that the

control measures are effectively working within the operational limits, and




quick notification and remedial actions taken when there is a deviation. The

documentation of the monitoring includes what to monitor, how to monitor,

where the monitoring is carried out, who will carry out the monitoring, who

will do the analysis and who receives the results for action.

A formal verification and auditing process needs to be established to

ensure that the WSP is working properly. Verification involves compliance

monitoring; internal & external auditing of operational activities; and

consumer satisfaction.

Management procedures can then be documented for standard and

incident operating conditions and the resultant corrective actions to be taken

when necessary. Emergency supplies, investigation plan, communication

procedures with stakeholders, reporting procedures and procedures for

regular review and management update are also included.

Supporting programmes should also be determined for each step of the

water safety plan, as the delivery of safe water through the WSP involves

managing people and processes. These programmes include training,

calibration, operation & maintenance, R&D, legal, hygiene and sanitation

aspects.

The entire WSP needs to be documented, presented and approved by

all stakeholders to allow “buy-in” and support. This is important if the WSP is

to be implemented effectively. There is also a need to include a provision for

the WSP to be reviewed and regularly updated.

4.1.4. Surveillance

Drinking water suppliers are legally and morally responsible for the

control of drinking water quality and the sufficiency of supply. The WHO

(2006)7 recommends the setting up of a separate surveillance agency

responsible for overseeing public health assessment in drinking water to

complement the water supplier in view of the conflict of interest between

public health and operational costs.




Drinking water surveillance requires the long-term constant

assessment of the safety and suitability of drinking water supply for the

protection of public health. Surveillance provides information, which should

be effectively managed and used, as a collaborative mechanism and support

for the surveillance agency and water supplier, for the prioritisation of water

supply improvements. However, the surveillance agency would also require

legal instruments and authority to use enforcement, which should be used

only as a last resort.

The basic parameters for adequacy of supply that the surveillance

agency needs to assess public health are:

• Quality – validation and compliance audit of the approved WSPs;

• Quantity – proportion of population using different levels of drinking

water supply;

• Accessibility – percentage of population with reasonable access to

improved drinking water supply;

• Affordability – tariff paid by domestic customers; and

• Continuity – percentage of the time when drinking water is available.

(WHO, 2006)7

WHO (2006)7 recommended surveillance be carried out by audit-based

or direct assessment approaches.

The audit-based approach basically requires the water supplier to

undertake assessment activities, verification testing of water quality and to

furnish all relevant information to the surveillance agency, while the

surveillance agency is responsible for 3rd party auditing to verify compliance.

Accredited external laboratories commonly carry out analytical services, paid

for by the water supplier. The surveillance agency needs to have the expertise

and capability to:

• Review and approve water safety plans;

• Audit the water safety plans implementation periodically (at regular

intervals, following significant incidents or changes to the systems); and




• Investigate and assess incident reports to ensure that the cause is

correctly determined and corrective actions taken and reported to

prevent reoccurrence of a similar situation.

The direct assessment approach will require the surveillance agency to

carry out independent testing of water supplies. The surveillance agency will

require its own or 3rd party analytical facilities and trained staff to carry out

sampling, analysis and sanitary inspection.

4.1.5. Other Recommendations

With a preventive approach, the WHO guidelines (2007)7 recommend

minimal dependence on end-point monitoring, as the sampling is meant only

as verification of water quality.

Simple and more frequent faecal indicator tests are recommended to

detect contamination in water supply. Faecal contamination is not distributed

evenly throughout the piped distribution system and can vary with local

conditions. The recommended minimum sampling frequencies for faecal

indicator tests are shown in Table 6.

Table 6 Minimum faecal indicator test frequency in distribution systems

Population Total no of samples per year

Point sources Progressive sampling of all sources over 3- to 5-year cycles

Piped supplies

5000 – 100 000 12 per 5000 population (rounded up)

>100 000 – 500 000 12 per 10 000 population plus additional 120 samples

>500 0000 12 per 100 000 population plus additional 180 samples

(WHO, 2006)7

Table 7 Minimum sample frequency for piped supply

Population Served No. of monthly samples

< 5000 1

5000 – 100 000 1 per 5000 population

> 100 000 1 per 10 000 population, plus 10 additional samples

(WHO, 1997)26




The principal source of the chemicals found in water will determine the

location and frequency of sampling. However, the WHO (2006)7 recognises

that source water sampling once a year may be adequate for stable

groundwater source, while the variable surface water source might require

higher frequency. For piped supply, the recommended minimum sampling

frequencies are based on the population served, as shown in Table 7. The

sampling frequencies for other supplies in small communities are attached in

Appendix BAppendix B – International Drinking Water Guidelines.

Each location where the samples are taken should be individually

considered, but the samples must be representative of the water source,

treatment plant, storage facilities, distribution network, customer delivery

points and points of use. The general criteria of the selection of locations are

that:

- Samples need to be representative of the different sources as it is

obtained or enters the system;

- Yield samples, representative of the conditions at the most

unfavourable sources or places in the supply system and points of

possible sources of contamination, need to be included;

- Sampling locations should take into account the number of inhabitants

served by each source in multiple source systems;

- Locations need to be uniformly distributed throughout the distribution

system, taking into account population distribution and proportional to

the number of branches or links;

- Samples need to be representative of the system as a whole and of its

main components;

- There is a need to sample water in reserved tanks and reservoirs and

there should at least be one sampling point directly after the outlet at

each treatment works; and

- Sampling locations can be fixed or variable. Fixed sites are useful in

allowing results to be compared over time, while local problems are

more readily detected using random locations.

(WHO, 1997)26




4.2. European Union

The European Economic Community (EEC) was originally set up to

create a common market between the constituent Member States, but has now

been extended to a large number of common policy goals which is directly or

indirectly related to attain conditions leading to a single market within the

combined territories of the member countries. The EEC was renamed as the

European Union (EU) in 1992 by virtue of the Treaty on European Union

(TEU). (Hedemann-Robinson M., 2007)27

The Single European Act amending the Treaties was enacted on 1 Jul

1987. The Act aims to create a single internal market and formulates a

European foreign policy. More importantly, it introduces explicit references

to the EU’s powers relating to environmental protection for the 1st time. This

includes:

‐ Article 100a which allows for environmental protection legislation

affecting the internal market to be adopted by the majority of member

states; and

‐ Article 130r, 130s & 130t, which specifies the objectives, means and

procedures for unanimous adoption of environmental legislation.

(European Community, 1996)28

The EU comprises of 27 member states, which are Belgium, France,

Germany, Italy, Luxembourg, Netherlands, Denmark, Ireland, United

Kingdom, Greece, Portugal, Spain, Austria, Finland, Sweden, Cyprus, Czech

Republic, Estonia, Hungary, Latvia, Lithuania, Malta, Poland, Slovakia,

Slovenia, Bulgaria and Romania. (Europa, 2008)29

What is unique about the EU is that there are distinct, separate

legislative, executive and judicial organs of government, the power of which is

transferred from the member states to the community by virtue of treaties and

that the community law overrides the national laws.





The EU adopts the following type of legislation:

‐ Non-binding recommendations or resolutions

‐ Regulations which are binding and directly applicable to Member

States and overrides national laws

‐ Decisions which are directly binding to the persons (member states,

individual and legal persons) they are addressed to; and

‐ Directives which member states are required to transpose and

implement through their national law or regulations within a specified

time period (normally 18 months to 2 years).


As illustrated in Figure 6, the EU water policy formation involves the

core European institution, Member States government and non-governmental

organisations with interest in water. The Council decides on the policy

objectives and directions, while the Commission develops and drafts the

directions into appropriate policy text and directives. The European

Parliament actively debates on the legislation and can amend the draft

legislation presented by the Council. The European Parliament shares the

responsibility of passing European laws with the European Council.

Representatives of sectors affected by water-related regulations and various

water-related organisations try to influence the process by lobbying. This

reflects the similar situation at the national level. The scientist and

technologist group is consulted on water-related technical issues and their

recommendations are critical to the nature of the policies.

Figure 6 Parties active in EU water policy process

(Kallis G. & Nijkamp P., 1999) 30

ORGANISED INTERESTS

EUROPEAN REPRESENTATIVES/

ASSOCIATIONS

SCIENTISTS TECHNOLOGISTS

MEMBER STATES’ GOVERNMENT

EUROPEAN PARLIAMENT

EUROPEAN COMMISSION

COUNCIL OF MINISTERS

NATIONAL LEVEL EUROPEAN LEVEL

EUROPEAN INSTITUTIONS




Kallis G. et al. (1999)30 describe EU water policies as split between

water use directives and water pollutant directives. Water use directives are

concerned with setting the Europe-wide quality standards of water intended

for a particular use that all Member States are to comply with, while water

pollutant directives deal with emission control and standards for discharges

into water.

4.2.1. Drinking Water Directives

The EU council (1998) 31 adopted the Drinking Water Directive

98/83/EC (DWD) on 3 November 1998 for all member states to transpose

into national law to ensure that potable water for consumption is clean and

wholesome for the protection of public health in the EU. This fulfils one of the

objectives specified in article 174 of the European treaty, which relates to the

protection of human health, aims at the highest level of environmental

protection and takes into account available scientific data (EU, 2008)32.

The DWD (1998)31 states that water intended for human consumption

is wholesome and clean if it contains no micro-organism, parasites and

concentration of substances that endanger human health; and meet the

minimum parametric values and requirements set out in the DWD. Member

States are allowed to impose stricter parametric values and add other

parameters for the protection of human health within their territory.

The parametric concentration values (PCV) are generally based on the

WHO guidelines and recommendations of the Commission's Scientific

Advisory Committee. The committee, comprising of Member States’

representatives and a chairman appointed by the Commission, carry out a 5

year review of the PCV and monitoring requirements of the DWD and propose

other measures relating to the DWD. (EC, 1998)31

The DWD (EC, 1998)31 specifies 2 microbiological parameters (5 for

water for sale in bottles or containers); 26 chemical parameters and 20

indicator parameters. The directive parametric values, indicator parameters,




sampling frequency and analysis specifications are clearly defined in the DWD

and are attached as Appendix C.

Member States are required to carry out regular water quality

monitoring programme based on the frequency and sampling points set out in

the DWD to show evidence of compliance. Samples taken must be

representative of the water quality throughout the year. Compliance sample is

collected at the point where the water is taken for consumption and use. For

piped supply, the sample is taken at the consumer’s tap. (EC, 1998)31

Any failure in meeting the parametric values has to be investigated

immediately to determine the cause of the failure. Member States have to

ensure that appropriate remedial actions are carried out as soon as possible

and give priority to their enforcement actions. Supply of water which

constitute a potential danger to human health need to be prohibited or

restricted. Article 10 in the DWD also requires that Member States ensure

that any materials and substances for new installations of water treatment and

distribution do not have an adverse impact on human health. (EC, 1998)31

Derogation, the act of failing or likely to fail the DWD standards, is

allowed if there is no likely danger to human health and if the water supply in

the area cannot be maintained by any other means. Member States can decide

on the 1st derogation for a period up to 3 years to allow remedial actions to be

taken. The Member States can inform the Commission of a 2nd derogation (up

to a period of 3 years); if the progress review showed that the progress made

in the 1st derogation is not sufficient. The Commission’s approval will be

required if there is a need for a 3rd derogation (up to a period of 3 years).

(EC, 1998)31

Adequate and up-to-date water quality information must be made

available to consumers. Member States publish and submit a report every 3

years on the water quality and the measures taken to fulfil the DWD. Arising

from these reports, the Commission will then produce a synthesis EU report

on water quality. (EC, 1998)31




4.3. United Kingdom

Figure 7 Map of UK

(CIA World Factbook, 2008)33

The United Kingdom comprises of

England, Scotland, Wales and Northern Ireland

(Figure 7). There are 12 water and sewerage

services providers and 15 water suppliers in the

UK as shown in Figure 8. Scotland and

Northern Ireland each has public-owned water

and sewerage service provider and independent

water quality regulator. The situation is unique

in England & Wales, as it is privatised with

several companies being subsidiaries of

international enterprises.

(Water UK, internet, 2008)34

4.3.1. England & Wales

May A. (2007)35 gives an overview of the main parties involved in the

water industry in England & Wales, summarised in Figure 9. The WHO is

the international health authority and provides the basis of all health-related

regulations and standards, though it is not strictly providing standards for the

EU Member States. The EU is the regional authority, which decides on the

regional standards for the Member States. The Department of Environment,

Food and Rural Affairs (DEFRA) is the UK government ministry responsible

for the water policies of UK. The regulatory agencies exist to ensure that

public water suppliers comply with the water regulations and support the local

authorities, which are responsible for regulating the private water supplies.

Water UK represents the public water supplier, while there are other

organisations representing the manufacturers. The Consumer Council for

Water acts as the consumer’s voice to protect consumer interests.


Christopher Chua

‐ 36 ‐ MSc in Water Regulation & Management

Dissertation 2008

Figure 8 The current UK water Industry

(Water UK, Internet, 2008)36


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Dissertation 2008

Figure 9 The drinking water industry in England & Wales

The water industry in England & Wales is regulated by different

government appointed regulators focusing on different key areas:

• Financial & economic – The Ofwat regulates the water services and

prices charges;

• Environmental – The Environmental Agency (EA) is responsible for

raw water quality and resources, abstraction, pollution control and

discharges into the environment; and

• Drinking Water Quality – The Drinking Water Inspectorate

regulates drinking water quality compliance.

(Water UK, 2008)37

Local Authorities

WHO (International Advisory)

European Union (Regional)

UK Govt Ministries (DEFRA)

UK Government Agencies (Regulatory)

Public Water Suppliers

Private Water Supplies

Consumer

Consumer Council for

water

Water UK & Other Associations

Region

al N

ational

(En

gland

& W

ales)


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Dissertation 2008

4.3.2. The Water Supply (Water Quality) Regulations

2000

Drinking water quality standards are specified in the Water Supply

(Water Quality) Regulations 2000 and are based on the 1998 EC Drinking

Water Directives. “Wholesome water” is defined by the water quality

standards in the regulations, which includes 2 microbiological & 26 chemical

Directive Standards, 2 microbiological & 10 chemical National Standards and

12 Indicator Parameters (This is because the 8 DWD indicator parameters

have been adopted as the National Standards). The regulations also specify a

catch-all standard that the water supplied does not contain any micro-

organism or substances at a concentration or value which would constitute a

potential danger to human health. The parameters, sampling frequency,

compliance location and analysis specification are shown in Appendix D.

(UK parliament, 2000) 38

The regulations (UK parliament, 2000)38 require public water

companies to pre-fix the water supply zone annually, which is limited to a

maximum of 100,000 consumers and must be of uniform water quality.

Audit monitoring is carried out to establish that the specifications of

the parameters in the regulations are satisfied, while check monitoring obtains

information on the organoleptic and microbiological water quality and the

drinking water treatment effectiveness for the purpose of satisfying the

provisions of “wholesomeness” in the regulations. The frequencies of the

compliance monitoring programme are specified within the regulations so

that compliance statistics are not influenced by significant over-sampling.

However, water companies may identify additional non-compliance sampling

programme for more information on water quality. (DWI, 2005)39

Sampling points are required to be selected at random unless there is

authorisation from the Secretary of State. Permanent sampling points are

allowed only if there is no adverse change on the parameter between the

sampling point and the consumer’s tap.


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Dissertation 2008

It is clearly stated in the regulations that water companies are required

to investigate any failure (or potential failure) and notify DWI of the cause of

the failure and the actions taken by the water company. The regulations also

set out actions taken by DWI once notification is made to either impose an

enforcement order or have the water company seek a departure, so that

remedial work could be carried out. An Authorised Departure (for Directive

standards) or Derogation (for National Standards) is only allowed for

parameters which pose no potential harm to human health and is only allowed

for a maximum period of 3 years. (UK parliament, 2000)38

To satisfy article 10 of the Drinking Water Directive (1983)31, the DWI

(2008)40, on behalf of Secretary of State for the Environment, Food & Rural

Affairs, approves materials and chemicals used by water companies that come

in contact with water, as stated in regulations 31 - 33 of the Water Supply

(Water Quality) Regulations 2000 (2000)38. This is known as the Regulations

31 approval and is carried out on a case by case basis.

4.3.3. The Drinking Water Inspectorate (DWI)

Section 57 of the Water Act 2003 (UK parliament, 2003)41 amended

Section 86 of the Water Industry Act 1991 (UK parliament, 1991) 42 to

specifically designate the Chief Inspector, on behalf of the secretary of state, to

independently carry out the powers and duties specified in sections 67 – 70 &

77 – 82 with respect to quality and sufficiency of supply of drinking water.

The Chief Inspector publishes an Annual Report on Drinking Water in

fulfilment of the requirements as stated in section 86(2b) of the Water

Industry Act 1991 (UK parliament, 1991)42. Section 86(2b) requires the Chief

Inspector to report to the Secretary of State on the status of the water industry

with respect to water quality.

Colbourne J. (2008)43 explains that the Chief Inspector is specifically

designated by legislation to be independent from the government in

discharging the specified duties and is subjected to judicial review on the Chief

Inspector’s competencies.


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Dissertation 2008

The DWI ensures that the drinking water supplied to customers in

England and Wales is safe and in compliance with the water quality

regulations by carrying out the following core duties:

• Carry out technical audit of public water companies;

• Initiate enforcement action as necessary for contraventions of the

wholesomeness standards or other enforceable environmental duties;

• Investigate incidents which adversely affect drinking water quality;

• Prepare cases for prosecution if there is sufficient evidence that water

unfit for human consumption has been supplied;

• Provide technical and scientific advice to Ministers and DEFRA officials

and the office for the Welsh Assembly Government on drinking water

policy issues,

• Identify and assess new issues or hazards relating to drinking water

quality and initiate research as required;

• Assess and respond to consumer complaints on drinking water quality

when local procedures have been exhausted;

• Assist in the Authorities’ approval process for substances, products and

processes used in the public water supplies;

• Provide authoritative guidance on matters such as the analytical

methods used in the monitoring of drinking water;

• Provide technical advice to local authorities responsible for enforcing

the Private Water Supplies Regulations 1991 (UK parliament, 1991)44

and regulating private water supplies; and

• Report to the EU on UK’s drinking water quality under the European

Drinking Water Directive

(Ofwat, 2006)45 (May A, 2007)35

The current staff and organisation structure of the DWI are shown in

Figure 10. The lean organisation is structured according to teams with

specific core functions.


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Dissertation 2008

Figure 10 Organisation of the DWI

(DWI, 29 May 07)46


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Dissertation 2008

The water industry in England & Wales operates on a self-regulatory

model. The DWI does not take or analyse samples or carry out investigations

or remedial actions. Instead the DWI provides an independent check on all

water quality data provided by water companies, carries out technical

assessments on whether the investigation and actions by water companies are

appropriate when there is a breach in standard and carries out audits for

prioritised high risk water supply systems.

Rouse M. (2000)47 confirmed that the technical audits comprise of the

following activities:

‐ An annual assessment, based on water quality and other compliance

information provided by companies

‐ Inspection of individual companies, focusing on whether the individual

components of the treatment processes as a whole, is functioning as

planned; identifying and mitigating areas of high vulnerabilities within

the systems which compromise drinking water quality; and the

accuracy of the companies’ sampling and analysis programme to ensure

a reliable measure of drinking water quality; and

‐ Interim checks made on particular aspects of compliance with the

regulations based on information provided periodically by the

companies.

May A. (2008)35 further elaborated that the DWI carries out inspection

checks on:

‐ Sampling & analytical arrangements (review of sampling programme,

audit of sampler, laboratory inspections);

‐ Reporting arrangements (audit trails);

‐ Compliance programmes (selected schemes audits, review of

programmes to meet standards; undertakings review)

‐ Public records (whether the results are correct);

‐ Appropriate treatment processes in the treatment works;

‐ Operation and maintenance of the treatment works and distribution

networks; and

‐ Consumer complaints.


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Dissertation 2008

The DWI has implemented a risk-based audit process to prioritise and

focus their audits in high risk systems and processes. The process utilises all

available information from water company data, inspector’s knowledge of the

issues, process types and sites to time of last inspections, and ranks the

systems and processes according to their risk. The inspectors then work

through the list in order of risks, ensuring that the high risk sites are audited

first using available resources. This is only possible and justifiable as water

companies are required to provide all relevant water quality data to allow the

DWI to get an accurate picture of water quality at the treatment works, service

reservoirs and supply zones. (May A., 2007)35

From 1990 to 2003, the water companies were only required to submit

annual compliance data to DWI for their assessment. Since 2003, the DWI

requires water companies to submit monthly returns of all compliance

sampling results to allow the:

• Creation of a database to rigorously analyse and assess the water

companies’ compliance with the standards; and

• UK to comply with the requirements specified in the European

Community Standardised Reporting Directive (91/692/EEC).

(DWI, 2003)48

The DWI database is the key support for the DWI in carrying out its

core duties more effectively. May A. (2007)35 found that the searchable water

quality database (with over three million results a year) aids the DWI in their

assessment, decision making and other regulatory functions. Taylor A. (28

Apr 08)49 shared that the database contains all records from the monthly

compliance data submissions, incident reports, public enquiries, DWI’s

investigations and other related information. The database allows the

creation of visual maps of hotspots, which are used for analysis and included

in the annual report. The DWI inspectors have the flexibility of working

anywhere by having restricted access to the database on the DWI server using

internet connections. Taylor A. (28 Apr 08) also confirmed that there is a

strict format for the inputs of the compliance data as stated in DWI

information letter 6/2003 (DWI, 2003)48, or the database will reject the data.


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Dissertation 2008

S.68 (1) (a) of Water Industry Act 1991 (UK parliament, 1991)42

requires water companies to supply wholesome water, as defined by the Water

Supply (Water Quality) Regulations 2000. The duty of the DWI, on behalf of

the secretary of state, is to consider enforcement when there is a breach in

regulations. As explained in Chapter 4.3.2, water companies are required to

notify the DWI of failures to supply wholesome water, the DWI thus provides

guidance to water companies on notification of such events in their

information letter 02/2004 (DWI, 2004)50.

Water companies are required to notify the DWI of all events, the

nature of which have, or are likely to have

• Adversely affected the quality and sufficiency of the water supplied by

them;

• Given rise to a significant risk to the health of the consumers;

• Been matters of national significance

• Attracted local or national publicity relating to the supply or causing

concern to consumers;

• Been reports of disease in the community associated with water supply.

The DWI will then carry out an investigation of the incident.

(DWI, 2004)50

The DWI (2008)51 defines an incident as a sub-set of events, including

combination, but not limited to the following:

• Any sudden and unexpected breach of part III of the Water Supply

(Water Quality) Regulations 2000 amendment regulations (England) &

2001 amendment regulations (Wales) on wholesomeness of water

supplied

• Any breach of Part IV of the above regulations on water treatment

• Any usual deterioration of water quality

• Any significant risk to the health of the consumer

• Significant consumer perception of water quality changes

• Significant consumer concern about the quality of the water supplied


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Examples of notification for the above events include any:

• Event or sequence of events leading to a significant and unexpected or

unusual deterioration in the quality of water at the source, on entering

supply, or at any point in the distribution, resulting in customer

concern

• Malfunction of the disinfection or pre-treatment equipment

• Notification made to local health authority under regulation 35

• Treated water sample with Cryptosporidium oocyst or Giardia cysts or

significant increase in cryptosporidiosis

• Burst mains or significant loss of supply or potential depressurisation

of any point in distribution system

• Suspected backflow/back siphonage

• Significant publicity or contact made by local consumer representative

or media interest

All other event notifications are not classified as incidents.

(DWI, 2008)51

The DWI inspectors use the flowchart in Figure 11 for their incident

investigation. The water company should contact the DWI, either by

telephone and email, as soon as it is aware of a notifiable problem or of a

developing situation, which might become notifiable. An interim report with

information set out in annex 4 of the information direction 03/2008 has to be

submitted.

Upon receipt of the initial notification, the DWI circulates outline

details of the events to DEFRA, Welsh Assembly government and key external

stakeholders (FSA, EA, DoH), as appropriate. Ministers may be advised of

high profile events or events in their constituencies.

Within 5 working days, the DWI will advise the company, in email or

writing, about whether the event is considered an incident, non-incident or

there is insufficient information to classify the event. If classified as an

incident, the DWI might require the company to submit a final 20-day report.


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Dissertation 2008

Figure 11 Assessment of Incidents Flow Diagram

(DWI, online, 2008)52

The DWI (2008)53 evaluates and determines:

• Cause of the event and whether it is avoidable;

• Company response and handling of the event;

• Lessons learnt to prevent future similiar events;

• If any breach of enforceable regulations occurred; and

• If water unfit for human consumption was supplied.

Notification of Event via Telephone/Other

means

Assessment of initial Report

72 hours

Classified as Incident?

5 days

3 Months*

1 Month ***

Full Report submitted by Water Company

Reclassified as a Non-Incident

Signing off of Non-Incident

Assessment and Investigation

Prosecution Assessment

YES NO

Completion of Prosecution Proceedings

Signing off of incident Following Actions upon

Recommendations

12 Months**

NO

3 Months*

YES

* Targeted time frames that may be extended should further investigation or information be needed.

** Targeted time frame that may be influenced by the Court.

*** Targeted time frame for this process from notification to report submitted by the Water Company


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Upon assessment, the DWI will issue a concluding letter to the

company and the relevant stakeholders. The concluding letter will include the

findings and conclusions of the assessment, and any recommendations which

the company can respond to within 20 working days.

If a non-trivial failure of a directive standard was contravened that is

likely to recur and was not due to consumers' tap, the DWI may invite the

water company to apply for an Authorised Departure (EC Directives Standard)

or Derogation (National Standard) provided there is no health risk involved.

This allows the company to temporary supply water that is not wholesome up

to a maximum of 3 years, provided the company carry out an undertaking to

rectify the issue. The DWI can also consider an enforcement order on the

water company to carry out specified rectification work for failures where

there is a health risk.

If the wholesomeness standard was contravened during the event and

the problem is likely to recur, the DWI may consider initiating enforcement

action under section 18 of the Water Industry Act 1991.

Investigation and prosecution for the supply of water unfit for human

consumption under s.70 of the Water Industry Act 1991 (amended under

section 20 of schedule 8 of Water Act 2003 - enforceable on 1 Oct 04) and s.57

of Water Act 2003 (amended S86 of Water Industry Act 1991) allows

prosecution of anyone whose action result in backflow or back siphonage

incidents which affects the quality of water in the distribution. Prosecution

will also be considered if:

• At least 2 consumers experienced illness as a result of or reject the

water supplied;

• Evidence indicates that the company does not have a due diligence

defence; and

• It is in public interest to prosecute. (38 out of 40 cases since 1990 were

successful prosecution.)

(DWI, 2008)51


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Dissertation 2008

The DWI (2008)54 carries out the Regulations 31 approval for products

and chemicals used by public water companies on behalf of the Secretary of

State as discussed in Chapter 4.3.2. The applicant submits all relevant

information on the product or chemical to be approved, which the DWI

regulations 31 team will review. The DWI might require further information,

testing at an approved laboratory or seeking expert advice before allowing

such products or chemicals to be used. At least once a year, the Secretary of

State issues a list of all substances and products for which approval has been

granted, refused, modified, revoked or prohibited. (DWI, 2008)55

Research on water quality issues, as a core duty, serves to augment the

other core duties of the DWI. The DWI manages a DEFRA-funded research

programme on drinking water quality and health. The purpose is to:

• Provide a scientific basis for policy decisions, both within the UK and in

international bodies like the EU, UN and WHO;

• Provide technical information to understand present and upcoming

drinking water contaminants on public health and consumer

acceptability;

• Obtain technical information to assist the DWI in carrying out its core

duties more effectively and efficiently; and

• Provide a basis for assessing regulatory activities’ impact on the public.

(Watts and Crane Associates, 2006)56

An annual research ideas meeting is held to brainstorm and prioritise

research projects to be carried out in the year. Representatives from DEFRA,

DWI, HPA, UKWIR, EA and other stakeholders will present their proposed

projects and the meeting will decide on the projects to be funded.

(Foster J. 28 Apr 08)57

The DWI drafts the specifications for the projects to ensure that there is

a clear objective and outcome. The most suitable procurement route,

including co-funding, single tender or Expression of Intent (EOI), is selected

for the project types. Upon tender closing, three independent scorers from

DWI assess the award of the contract by using a scoring system. The most


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Dissertation 2008

important criterion is to determine if the proposal is realistic. The scoring

also includes pricing, as the projects are government-funded and there is a

need to be transparent. (Foster J. 28 Apr 08)57

Research projects are usually carried out by private consultants,

academics, commercial research companies and water companies. The DWI

Science and Strategy team manages the research project by monitoring

progress, meeting with the contractor, processing/approving payment,

reviewing and commenting on reports and evaluating the research project

upon completion. (Foster J. 28 Apr 08)57

May A. (2006)58 conclude that “privatisation has achieved significant

benefits in drinking water quality, but only with strong regulation and a

regulator specifically dedicated to drinking water quality.” This would also

apply to any water supplier, whether private or public. The reason is that the

regulations should be based on evidence and facts to show where the

companies are meeting the regulatory requirements, and where the

improvements have to be made in the water systems.


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Dissertation 2008

5. Metaldehyde-containing pesticide in the UK

5.1. Metaldehyde

Metaldehyde is the common active component for molluscicide pellets

used for snail and slug control. The compound is also poisonous to animals.

Metaldehyde is also used as camping stove fuel and was used in 1981 – 1982 in

a cloud seeding experiment at the University of Utah. (Wikipedia, 17 Jun 08)59

A “cyclic polymer of acetaldehyde”, metaldehyde is an easily fractured

colourless crystal with powdery appearance, tasteless and has a formaldehyde

odour. It is soluble in benzene and chloroform; slightly soluble in diethyl

ether and ethanol, but is insoluble in acetone and acetic acid. Metaldehyde

will also polymerise at high temperature (>80○C) and by strong acid (WHO &

FAO, 2008)60. Figure 12 provides more information. Clayden J. et al

(2001) 61 wrote that metaldehyde is formed from acetaldehyde with

hydrochloric acid (HCl) below 0○C and on heating, reverts back to

acetaldehyde. Bieri M. (2003) 62 noted that metaldehyde is a pure

hydrocarbon which degrades finally to water & carbon dioxide after first

degrading to acetaldehyde and then into acetic acid. Polymerisation is the

chemical process of substances merging to form new compounds (Nathan et al,

1975)63.

Figure 12 Information profile of Metaldehyde.

Synonyms: Metacetaldehyde Trade names: AntimiliceR; AriotoxR; CekumetaR;

DeadlineR; HalizanR; LimatoxR; Limeol GR; MetaR; MetasonR; MifaslugR; NamekilR; Slug DeathR; Slug Fest Colloidel 25R; SlugitR; Slug-ToxR.

IUPAC name: r-2, c-4, c-6, c-8-tetramethyl-1,3,5,7-tetroxocane. CAS name: 2,4,6,8-tetramethyl-1,3,5,7-tetraoxacyclooctane. CAS registry number: 108-62-3. (The homopolymer is 9002-91-9). Molecular formula: C8H16O4 Relative molecular mass: 176.2 g/mol Density 1.27 g/cm3

Solubility: Water @ 17○C - 200 mg/litre Water @ 30○C - 260 mg/litre

Structural formula:


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Metaldehyde is effective by contact (absorption through skin or lungs)

and by ingestion (absorption through the gastrointestinal tracts). The

effective single dose which will kill off 50% of the rat population in laboratory

tests (LD50) is about 227 mg/kg body weight (bw). Humans can experience

symptoms of poisoning with a low dose of only a few mg/kg of their body

weight. Other toxicity information can be found in Table 8. The WHO

(2005) 64 classified metaldehyde as a class II or moderately hazardous

chemical.

Table 8 Toxicity studies on metaldehyde

Toxicity – mammals Oral LD50 Dermal LD50 4-hr inhalation LD50 Rat 227-690 mg/kg bw >2275 mg/kg bw 200 µg/m3 Mouse* 200 mg/kg bw 203 µg/m3 Guinea pig 175-700 mg/kg bw Rabbit 290 – 1250 mg/kg bw * An oral dose of 1000 mg/kg bw can kill mice within 2 hrs of exposure. Symptoms of poisoning 10 minutes after dosing include sedation, shivering, whole body tremors, tonic-clonic convulsions and death. Toxicity - Man

>50 mg/kg Drowsiness, tachycardia, spasms, irritability, salivation, abdominal cramps, fever, facial flushing, nausea, vomiting

50 – 100 mg/kg Ataxia and increased muscle tone 100 – 200 mg/kg Convulsions, tremors and hyperflexia

400 mg/kg Coma and death Toxicity – Non-mammals

Rainbow trouts 96-hr LC50 = 62 µg/m3 Bluegills 96-hr LC50 = 10 µg/m3 Chickens Minimum lethal dose of 500mg/kg bw

Ducks Minimum lethal dose of 300 mg/kg bw

Pan UK (2008)65 provides an explanation of the following physical

properties of pesticides in measuring their interaction with the environment:

• Half life (DT50) – defined as the time required for half of the pesticide

present after application to degrade. The time depends on temperature,

soil pH, soil microbe content, exposure to light, water or oxygen. This

is further sub-divided into soil half-life (in soil), photolysis half-life

(exposure to light) and hydrolysis half-life (reaction with water).


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• Water solubility – measures “how readily the chemicals dissolve in

water” and determines the likelihood of a pesticide being transported

away from the application site by run-off.

• Adsorption coefficient, Koc – measures the chemical’s adhesion strength

to soil and is defined as “the ratio of mass of pesticide adsorbed per unit

mass of soil to mass of pesticide remaining in solution at equilibrium”.

Koc is dependent on type of soil and soil pH. High Koc value indicates a

preference to soil adhesion rather than to dissolving in water.

• Octanol-water partition coefficient, log Kow – measures chemical

distribution between two immiscible solvents (polar water and non-

polar octanol) and is defined as the “ratio of the concentration of

pesticide in the octanol layer to the concentration of the pesticide

dissolved in the water layer”. Low log Kow value indicates the chemical

is more hydrophilic and more soluble in water.

As shown in Table 9, it takes about 10 days for metaldehyde to

degrade in soil. Bieri M. (2003)62 claimed that metaldehyde has a DT50 of

about 5.3 to 9.9 days in average German top soil under aerobic conditions and

expects metaldehyde to have a DT50 of 12 days in water. However, the US

Environment Protection Agency (EPA) (2006)66 stated that metaldehyde has a

half-life of 2 months in aerobic soil and >200 days in anaerobic conditions.

Table 9 Metaldehyde properties table

Common Name

Pesticide Movement

Rating

Soil Half-life (days)

Water Solubility (mg/l)

Sorption Coefficient (soil Koc)

Metaldehyde Low 10 230 240

(National Pesticide Information Centre, 2008)67

Rumsby P. (2007)68 stated that metaldehyde is one of the emerging

contaminants that several UK water companies are facing, as it has recently

exceeded the individual pesticide standard of 0.1 µg/l in 2007. Rumsby P.

(2007)68 speculated that there could be a higher usage of the molluscicide in

the wet 2007 summer to control snails and slugs and that metaldehyde might

not be removed by GAC due to its low Kow value greater than 2.


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WRC (2008)69 is now commissioned by some of the water companies to

work with them to carry out research to identify suitable treatment processes

for the removal of metaldehyde. This in turn will help the companies to

decide on appropriate treatment processes and provide evidence to support

their discussion with DWI and other relevant authorities on proposals to

resolve the metaldehyde issues.

5.2. Role of Regulation

The DWI (2008)70 reported that in the western region, 2 out of 37, 239

tests for individual pesticides exceed the standard of 0.10µg/l for metaldehyde,

although there was no PCV breach for total pesticides. The DWI (2007)71 is

considering enforcement action after evaluating the incidents and found that:

• There was inadequate notification of relevant authorities for the

contravention;

• There was little priority given to analysis of metaldehyde when the

increased risks of hazards are known; and

• Bristol Water plc failed to meet the requirements of the Water

Undertakers (Information) Direction 2004

The DWI (2008)72 further reported that Sutton and East Surrey Water

in the Thames region found metaldehyde in its reservoir and in the final water

after extending its raw water monitoring programme. The extension of the

raw water monitoring programme was a result of the DWI being critical of

Sutton and East Surrey Water for not taking any action, nor was it mindful of

the river water quality, despite being made aware of a potential source water

pesticide problem three months earlier.

Allen J. (2008) 73 said that the DWI is currently viewing the

metaldehyde contraventions as any other breaches in the standard. The DWI

is investigating the situation and ensuring that the water companies are

working to resolve the issues to prevent reoccurrence.

Bristol Water plc (2008)74 commented that from 2007, one of their

greatest current challenges is the high metaldehyde pesticide levels found in


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raw water. In 2007, 2 out of 31 tests for metaldehyde, in water sample from a

supply point, were tested with a maximum concentration of 0.209µg/l, which

failed to meet the individual pesticide standards of 0.1µg/l.

Bristol Water plc (2008)74 carries out a pesticide monitoring strategy

based on an independent assessment of the types of pesticide used within

their catchment areas, and only carries out analysis for any pesticide with a

concentration greater than 10ng/l. It was found that metaldehyde

concentration in raw water and after treatment exceeded the standards at

certain times of the year and under certain conditions, although the

concentration levels detected in the treated water were not considered to be

hazardous to human health. Nevertheless, Bristol Water plc has

commissioned research to determine suitable treatment process to treat the

water to the required standards.

The Control of Pesticide Regulations (COPR) and Plant Protection

Products Regulations (PPPR) legislation regulates the use, supply, storage and

advertisement of pesticides in the UK. The Pesticide Safety Directorate (PSD)

is responsible for agricultural pesticides, while the Health & Safety Executive

(HSE) are responsible for non-agricultural pesticides. (PSD, 2008)75

PSD (2008) 76 approved 179 products containing metaldehyde from

about 40 companies, for use with conditions in the UK until 21 Dec 2013.

However with the enforcement of EC regulation 396/2005 on the maximum

residue levels (MRLs), PSD (2008)77 has revoked about 127 products for on

label use on Potato and Cauliflower crops.

5.3. Case Study

The company was aware of industry concerns of metaldehyde occurring

in drinking water supplies in December 2007, where the increase was likely

due to increased usage within the catchment areas and heavy rainfall during

the period. The company’s pesticide sampling programme did not include

metaldehyde, as no significant quantities were detected previously in their

catchments. (Water company, 2008)78


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Investigation sampling of raw and final water samples at four water

treatment works were carried out on 14 Dec 07. Specialised analysis was

carried out by an external professional laboratory. The results of the analysis

indicated that metaldehyde (concentration range of 0.107µg/l to 0.125µg/l)

was detected above the PCV at three of the water works. The analysis of re-

sampling of the final water samples from three of the water works on 23 Jan

08 found that metaldehyde above the PCV was still detected from samples

taken at one of the water treatment works. Further sampling on 25 Jan 08 at

this water treatment works and its distribution system did not find any sample

with metaldehyde above 0.1µg/l. (Water company, 2008)78

A further survey of metaldehyde carried out in the surface water

treatment works in the region and a bulk supply from another water company

from the same region on 25 – 29 Jan 08 revealed metaldehyde above or at

PCV in several raw water sources and two treated water samples. From Feb to

Mar 08, the company continued to carry out surveys to determine the risk and

treatment removal efficiency for metaldehyde and found metaldehyde levels

above 0.1µg/l at two new monitoring points and one of the earlier water works.

The company has since included a monthly sampling programme for

metaldehyde for the region for risk assessments purposes.

(Water company, 2008)78

The water treatment works treats raw water with physical-chemical

treatment processes including storage reservoirs, coagulation, clarification

(dissolved air flotation or hopper bottom clarifiers), rapid gravity filtration,

GAC adsorption and chlorine disinfection. One of the treatment works is even

fitted with pre-ozonation and ozone before GAC adsorption. Based on the

results of the sampling analysis and from the water industry sources, the

company concluded that GAC and ozone might not remove metaldehyde

efficiently. (Water company, 2008)78 & 79

The external professional laboratory used gas chromatography-mass

spectrometry (GCMS) following solid-phase extraction (SPE). This analytical

method is partly validated and accepted by UKAS & DWI, but is not UKAS-


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accredited yet (Personal communication, 2008)78. Although the company was

concerned about the results obtained from the analysis of sample having

discrepancies (discussed below), the external professional laboratory claimed

that further investigation indicated that the method used is specific to

metaldehyde and is robust. Nevertheless, the company intends to work with

all relevant stakeholders on establishing a properly accredited analytical

method for metaldehyde. (Water company, 2008)78

An analysis of the results provided by the company (Water company,

2008) 78 indicates the following:

• Some of the raw water samples were not available for comparison with

treated water samples which indicated metaldehyde above PCV;

• Some of the final treated water has a higher metaldehyde concentration

than post-GAC sample, although all results were above the PCV;

• Many of the raw water samples have a lower metaldehyde

concentration than the final treated water sample; and

• The time of collection of some raw water samples was later than the

time of collection of the downstream final treated water sample.

As a result of a number of water companies facing metaldehyde

contravention, a meeting was held in Apr 08 to discuss the issue. This

meeting was attended by the DWI, EA, Water UK, and representatives from

manufacturers and water companies. It resulted in finding ways to investigate

and proposing solutions to the challenge, such as

• Reformulation of slug pellets to reduce solubility;

• Comprehensive education programme for users;

• Inter-laboratory trials on verification of analytical method

• Research into treatment options for removal of metaldehyde

(Government Agency, 2008)80


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6. Water Situation in Southeast Asia

6.1. Association of Southeast Asian Nations

The Association of Southeast Asian Nations (ASEAN) (2008) 81 was

established on 8 Aug 1967 to form an ASEAN community with the objective of

regional peace, stability and economic co-operation and social-cultural

development. The fundamental principles of ASEAN, contained in the Treaty

of Amity and Cooperation in Southeast Asia (TAC), primarily rely on

recognition of equality and sovereignty of each member country; non-

interference in the internal affairs of other member countries; peaceful

resolution of differences and intra-national issues; and effective co-operation

among member countries.

Figure 13 Map of ASEAN

ASEAN comprises of 10 Southeast Asian countries (as shown in

Figure 13), namely Indonesia, Malaysia, Philippines, Singapore, Thailand,

Brunei Darussalam, Vietnam, Lao People Democratic Republic (PDR) (or

Laos), Myanmar and Cambodia. In 2006, ASEAN has 560 million people, 4.5

million square kilometres, about US$1,100 billion in combined gross domestic

product and about US$1,400 billion in total trade. (ASEAN, 2008)81


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The annual Meeting of the ASEAN Heads of State and Government is

the highest decision making body in ASEAN and convened the ASEAN

Summit every year. The ASEAN Standing Committee coordinates the work

carried out in between the annual ASEAN Ministerial Meeting. Member

countries take turn to chair the ASEAN summit and meetings. Regular

Ministerial meetings on specific sectors are supported by committees of senior

officials, technical working groups and task forces. There are also several

specialised bodies and arrangements promoting inter-governmental

cooperation in various fields. This is illustrated in Figure 14. The Secretary-

General of ASEAN is appointed on a five-year term, and accorded ministerial

status, to initiate, advise, coordinate, and implement ASEAN activities.

(ASEAN, 2008)81

Figure 14 ASEAN Organisation structure

(ASEAN, 2008)81

In 1997, the ASEAN leaders adopted the ASEAN vision 2020 which

aims to build an outward-looking, peaceful, stable and prosperous group of

Southeast Asian nations. One of the aims of the ASEAN Vision 2020 calls for

“a clean and green ASEAN with fully established mechanisms for sustainable

development to ensure the protection of the region's environment, the

sustainability of its natural resources and the high quality of life of its

ASEAN Summit

ASEAN Economic Ministerial

Meetings (AEM)

Senior Economic Officials meetings

(SEOM)

Sub‐committees/ Working Groups

ASEAN Ministerial

Meeting (AMM)

ASEAN Standing Committee (ASC)

Working Group

Senior Officials Meeting (SOM)

Working Group

ASEAN secretariat

ASEAN Finance Ministerial

Meeting (AFMM)

ASEAN Senior Finance Officials Meeting (ASFOM)

Sub‐committees / Working Group

Others

Committees

Sub‐committees / Working Group


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Dissertation 2008

peoples." This highlights the emphasis placed by ASEAN in recognising that

sustainable development and environmental protection as instrumental in

long term economic growth and social developments in the region. The

ASEAN governance environmental structure to develop, coordinate and

implement environmental initiatives and programmes is shown in Figure 15.

(ASEAN, 2008)82

Figure 15 ASEAN environmental governance structure

The ASEAN Working Group on Environmentally Sustainable Cities

(2008)83, chaired by Singapore, was formed in Jun 2003 to develop strategies

and action plans for the Regional Environmentally Sustainable Cities

Programme (RESCP). The RESCP focuses on economic developments of

cities in the region in conjunction with the sustainable enhancement of the

living environment within the city in the area of clean air, clean land and clean

water. In the area of clean water, part of the strategies and programmes to

achieve good accessibility and quality of water supply for ASEAN cities include:

‐ Enforcement of efficient supply and use of water by reviewing and

enacting water policies and legislation; and

‐ Monitoring of water quality standards for drinking water by developing

ASEAN indicators, benchmarks and associated monitoring programme

on water sources quality, supply and accessibility.

ASEAN Summit (ASEAN Heads of state/Government)

ASEAN Ministerial Meeting (AMM)

(ASEAN Foreign Ministers)

ASEAN Standing Committee (ASC)

ASEAN Ministerial Meeting on the Environment

(ASEAN Environment Ministers)

Secretary General of ASEAN

ASEAN Senior Officials on the Environment

(ASOEN)

ASEAN Secretariat (Bureau for Resources

Development)

ASEAN Working Group on Nature

Conservation & Biodiversity (AWGNCB)

ASEAN Working Group on Coastal and Marine

Environment (AWGCME)

ASEAN Working Group on Multilateral Environmental Agreements (AWGMEA)

ASEAN Working Group on

Environmentally Sustainable Cities

(AWGESC)

ASEAN Working Group on Water

Resources Management (AWGWRM)


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The ASEAN Working Group on Water Resources Management

(AWGWRM) focuses on the long term sustainable integrated water resources

management plan to ensure sufficiency of water supply for ASEAN. One of

the key needs in the ASEAN Strategic plan for water resources management

(2005)84 is to develop a reporting system for a common set of water quality

standard and parameters across ASEAN for evaluation and analysis.

Table 10 Water statistics for Southeast Asian countries (1995 & 2004)

Country Population

Drinking water coverage

House connections for drinking water

Urban (%)

Rural (%)

Total (%)

Urban (%)

Rural (%)

Total (%)

Urban (%)

Rural (%)

2004 water statistics Cambodia 19 81 41 64 35 9 36 2

Indonesia 47 53 77 87 69 17 30 6

Lao PDR 21 79 51 79 43 14 44 6

Malaysia 64 36 99 100 96 94 98 87

Myanmar 30 70 78 80 77 6 16 2

Philippines 62 38 85 87 82 45 58 23

Singapore 100 0 100 100 100 100

Thailand 32 68 99 98 100 38 85 16

Brunei* - - - - - - - -

Vietnam 26 74 85 99 80 24 73 6

1995 water statistics Cambodia 14 86 29 4 54 29 25 0

Indonesia 36 64 74 13 90 28 65 4

Lao PDR 17 83 49 13 79 44 43 6

Malaysia 56 44 98

100 98 96

Myanmar 26 74 61 5 85 17 53 1

Philippines 54 46 87 31 92 46 81 13

Singapore 100 0 100 100 100 100

Thailand 30 70 97 32 98 76 97 13

Brunei* - - - - - - - -

Vietnam 22 78 68 11 91 44 61 1

* Statistics for Brunei are not available

(WHO &UNICEF, 2008)85

The UN (2008) 86 reported that the percentage of population with

access to clean water in urban areas have decreased from about 94% in 1990

to 89% in 2005, while the percentage in rural areas has increased from about

68% in 1990 to about 76% in 2004. The decrease in percentage for the urban


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areas appears to be due to the fact that the service delivery systems are unable

to keep pace with the rapidly growing population. As seen in Table 10, there

is a shift in the population from the rural areas to the urban areas. Other than

Singapore, Malaysia and urban Thailand, the percentage of houses with direct

connections for drinking water is very low.

Biswas A. (2003)87 believes that water management solutions must be

found within the developing countries, rather than just copying solutions from

other parts of the world. This is because of the differences in climatic and

local water issues. In Southeast Asia, 80% of the annual rainfall is focused

within 15 to 20 non-consecutive days within the monsoon period, which lasts

about two to three months, and it is relatively dry the rest of the year.

Therefore, ASEAN countries have to manage the large quantities of water

within those periods for flood prevention and water supply.

The Asian Development Bank (ADB) (2005)88 recommended the need

for establishing a regulatory framework for water services in Asian countries.

As the provision of water services is a natural monopoly in a city, companies

could exploit their control with high tariff and inequitable service delivery

while governments could keep water charges too low for political gains.

Resource and economic regulations will ensure that all stakeholders’ interests

are catered for and that water services are efficient and cost-effective. Based

on ADB’s experience in Asia, there is a need for competent, credible and

independent regulators within a transparent regulatory framework

throughout Asia and that subsidies are the purview of the government and not

the water services providers.

ADB recognises that Singapore’s water agency, PUB, responsible for

both water services and policy implementation, is able to self-regulate well

because of the discipline and commitment by the government. Although most

Asian countries self-regulate, they are unable to do so as well as Singapore,

because legislation and policies are often overlooked and the agencies lack the

autonomy to manage their own affairs, even though it is legislated but it is not

enforced. ADB recommends that governments need to become regulators


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instead of just service providers. Regulations are required to bring

transparency, accountability, equitability and efficiency to the water sector

and must apply to all public and private operators. Regulatory bodies must

protect both consumers’ and operators' interests and need only ensure that

policies and legislation are conformed with. (ADB, 2003)89

6.2. Singapore

Located in Southeast Asia between

Malaysia and Indonesia, Singapore is a

tropical island city state with a land mass

of 682.7 sq km, a population of 4.6

million people and virtually no natural

resources (CIA, 2008)90 . Tortajada C.

(2006) 91 noted that Singapore is

considered a water scarce country

because of the limited land area to store

the annual rainfall of 2400 mm/yr,

making water supply one of the

Singapore Government’s main concerns.

Figure 16 Map of Singapore

CIA, 4 Jul 08)90

At the dialogue session during the inaugural Lee Kuan Yew Water Prize

Award Ceremony, Singapore’s Minister Mentor Lee Kuan Yew revealed that

Singapore's quest to be less dependent on Malaysia for its water supply came

about from day one when the country separated from Malaysia in 1965. Then

the Prime Minister of Singapore, Mr Lee believed that technology would steer

Singapore towards self-sufficiency and set up a unit within the Prime

Minister’s Office to systematically plan to make every drop of water in

Singapore potable (Channel Newsasia, 25 Jun 08)92. This highlights the need

for any country to put in place a long term sustainable water resources

management strategy. It also clearly shows that the Singapore government

sees water as an important strategic resource for survival, public health and

economic development.


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The World Bank (2006)93 highlighted that the core water policy in

Singapore is to ensure a long term sustainable clean water supply. This

follows tremendous efforts in the 1980s to establish a strictly enforced

environmental, legal and management system; integrated urban land-use

planning; pollution clean-up and control systems and the construction of a

complete urban sanitation system.

Totajada C. (2006)91 believes that Singapore’s success in water

management is due to:

• Concurrent emphasis on water supply and demand management;

• Institutional effectiveness; and

• Creating an enabling environment, including strong political will, an

effective legal & regulatory framework and an experienced and

motivated workforce.

During the World Water Week Conference 2007 held in Stockholm,

Sweden on 15 Aug 07, the Singapore government and WHO signed a

partnership agreement to work together in promoting safe management of

drinking water globally. Mrs Susanne Weber-Mosdorf, WHO's Assistant

Director-General for Sustainable Development and Healthy Environments,

commented that "Singapore is an exemplary model of integrated water

management and WHO hopes to work closely with Singapore to share such

expertise in water management with its Member States."

(WHO & MEWR, 2007)94

Deere et al (2007)95 reported that the main finding of the feedback

from the WSP training of trainers workshop, held in Singapore on 3 – 5 Dec

07, is that while WSP trainers agree that implementing WSPs would be useful

in improving water quality and the reliability of water supplies, water utilities

are unlikely to implement WSP unless they are legally obliged to do so, as the

WSP will not be their main priority. Water regulators would be required to

implement legislation or provide incentives to encourage water suppliers to

implement WSP.


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Dissertation 2008

6.2.1. Water Quality Regulations

The Ministry of Environment and Water Resources (MEWR) is

responsible for ensuring a sustainable living environment for Singaporeans

and focuses on the management of water, land, air and public health. MEWR

has two statutory boards, the National Environment Agency (NEA) and PUB

(the national water agency) to carry out the operational undertakings. PUB is

responsible for water issues, while NEA is responsible for issues relating to the

quality of the living environment in Singapore, environmental protection and

environmental public health. Both statutory boards are answerable to the

Minister for Environment & Water Resources and the Government of

Singapore in discharging their responsibilities. The current Singapore water

quality regulatory model is summarised in Figure 17. (MEWR, 2008)96

Within MEWR, the Water Studies Division (WSD) is responsible for the

strategic oversight of water issues in Singapore, including the water master

plan, pricing, legislation, policies and planning considerations. MEWR also

takes on the role of regulating the efficiency and performance of PUB, the sole

public water supplier. (Ministry, 2008)97

PUB is responsible for the technical and operational requirements of

water supply. The country’s water collection and drainage systems, reservoirs,

public water treatment plants, public water distribution networks, sewerage

systems, water reclamation plants, public NEWater factories and NEWater

distribution networks are owned and managed by PUB. Under the public-

private-partnership (PPP), PUB also purchases water from private-owned

NEWater factories and desalination plant, carried out under the design, built,

owned and operate (DBOO) arrangements. NEWater is Singapore’s third

national tap or water source and is produced from treated used water using

dual-membrane filtration and UV disinfection. Chapter 6.2.2 discusses this

further. (PUB, 2008)98


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Figure 17 Current Singapore water quality regulatory model

Since Jan 08, MEWR has worked with NEA to introduce the new

Environmental Public Health (Quality of piped drinking water) Regulations

2008, which becomes enforceable in Aug 2008. The newly formed Drinking

Water Unit (DWU), under the NEA’s Environmental Public Health

Department, is responsible for regulating water quality for both public and

private water suppliers. As such, the DWU is responsible for approving the

WSPs that PUB and other private water suppliers will prepare. The DWU is

PUB-owned drainage

systems, reservoirs, water

treatment works,

NEWater factories,

sewerage systems

Private owned NEWater

factories and

desalination plant

owned & operated under

the PPP arrangement

Private water supplies for

internal consumption

(campsites on offshore

islands)

– NEA is responsible for

water quality

Water Supply system to household, public buildings,

private buildings and industries

Ministry of Environment and Water Resources

Water Services Division

‐ Responsible for overall strategic policy on all water issues

‐ Formulates policies for water industry

‐ Regulates PUB on efficiency & performance

‐ Determines the tariff structure for public drinking water supplies

PUB

‐ Manages the entire water cycle

‐ Responsible for integrated urban

water resources management

‐ Sole public drinking water supplier

(except for small private supplies

for internal consumption)

‐ Regulates operational

requirements for water supply

system (including plumbers)

‐ Operational training for utilities

National Environment Agency (NEA)

‐ Environment and water quality regulator

‐ Responsible for approval of Water Safety

Plans and sampling programme

‐ Regulations sets the WHO

guidelines (1 microbiological, 3

physical, 3 radiological, 94 chemical

parameters) for quality parameters

and sampling frequency

‐ Responsible for regulating water quality of

private water supplies


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working closely with the WHO in developing and promoting the water safety

plans amongst developing member states and is a member of the WHO

Regional Office for Europe’s (WHOROE) International Network of Water

Regulators. The WHOROE (2008)99 explained that only regulators are invited

to join this network for the purpose of knowledge sharing and networking.

While there are limited private piped water supplies, these are mainly

for internal use in the offshore islands and there is usually no tariff charged,

so the tariffs are not regulated. However, NEA is responsible for regulating

the water quality for these water supplies. With the new regulations, MEWR

is working closely with PUB and NEA on their role in regulating the private

water supplies. It is likely that PUB will regulate the technical efficiency of

these water supplies, while NEA is responsible for the public health aspect of

water quality. (Personal communication, 2008)97

The Public Utilities Act 2001 (Singapore Government, 2001)100 was

enacted to reconstitute the Public Utilities Board (PUB) and matters

connecting to water services. S.6 of the Act specifies the functions and duties

of the board including, amongst other things, the responsibilities to “secure

and provide an adequate supply of water at reasonable prices” and “regulating

the supply of piped water for human consumption”. PUB is also responsible

for the levy and regulates the tariffs for water supplied for human

consumption, but the Minister’s approval is required for setting the tariff

structure. S.41 of the Act also stipulates that only PUB is allowed to supply

piped water for human consumption, unless explicit approval with conditions

is granted by PUB.

The Public Utilities (Water Supply) Regulations specifies that water

meter and water saving devices are mandatory in Singapore, unless

exemptions are approved by PUB (World Bank, 2006)93. It seemed highly

unlikely that PUB will allow exemption in the public supplies, as this will have

an impact on the tariff collection and the efficient use of drinking water.

The Minister for Environment and Water Resources appoints the

Director-General of Public Health to discharge the duties specified in the


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Environmental Public Health Act 1987 (EPHA) under section 3 of the Act. S.

58 requires the approval of the Director-General for any wells, tanks or

reservoirs used for drinking, domestic or other purposes. S.78 – 80 of the

EPHA specifies that only wholesome or unpolluted water may be sold for

human consumption and allows NEA to introduce regulations to define water

quality standards. (Singapore Government, 1987)101

Although Singapore has always adopted the WHO guidelines on water

quality, the Environmental Public Health (Quality of piped drinking water)

Regulations 2008 is the first to be introduced that legally defines water quality

standards. The specified water quality parameters, attached as Appendix E,

include 1 microbiological parameter, 95 chemical parameters, 3 radiological

parameters and 3 physical-chemical parameters. These are essentially

extracted wholesale from the WHO Guidelines for Safe Drinking Water. The

regulations also require all water suppliers to implement a WSP and sampling

programme, approved by the Director-General, which has to be reviewed

annually. (Singapore Government, 2008)102

NEA also produced a “Code of practice on piped drinking water

sampling and safety plan” to help water suppliers in complying with the

regulations. The code of practice (NEA, 2008) 103 recommends a basic

sampling for microbiological parameters only at the frequency specified in the

WHO guidelines (as shown in Chapter 4.1.5), while the minimum frequency

of the comprehensive sampling plan for all parameters specified in the

regulations is at least once a year, except those approved and identified as not

of concern.

Lye L.H. (2006)104 argued that environmental laws can be effectively

enforced only if an effective system of governance is established, starting with

effectively organised government institutions, offices and enforcement

agencies. Lye L.H. (2006)104 concluded that Singapore owes its success in

environmental management to its merit-based systems, political leadership,

administrative service and civil servants in the various environmental

agencies.


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Dissertation 2008

6.2.2. Integrated Water Resources Management

PUB (2008) placed equal emphasis on both components of IWRM -

water supply and water demand management. This is neatly summed up in

its vision “Water for All: Conserve, Value, Enjoy” (MEWR, 2008)106. However,

water supply management will be the main focus of this chapter.

Figure 18 Closing the Water Loop in Singapore

(PUB, internet, 2008)105

Since 2001, PUB (2008) 105 manages, in an integrated manner,

Singapore’s water resources from drainage systems, rivers, reservoirs,

waterworks, distribution network, water reclamation plants, NEWater

factories and sewerage systems to optimise Singapore’s limited water

resources. Using advanced technology, PUB short-circuit the water loop with

NEWater (reclamation of treated used water) and desalination as shown in

Figure 18. Some of the key water statistics can be found in Table 11.


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Table 11 Water resources statistics for Singapore

Water Resource Management Unit 2005 2006 2007

Drinking water (% access) % 100 100 100

Adequate sanitation (% access) % 100 100 100

Drinking water quality (meeting WHO standard) % 99.96 99.99 99.96

Water consumption as % of water demand met by total water resources

% 100 100 100

Unaccounted for water % 5.0 4.5 4.4

No. of accounts served per employee - 396 400 393

Monthly bill collection efficiency % 99 99 99

Monthly bill collection efficiency Days of sales outstanding

33 32 32

Water Supply Unit 2005 2006 2007

No. of raw water reservoirs in Singapore - 14 14 14

No. of desalination plants - 1 1 1

Sales of potable water in Singapore - Domestic - Non-domestic

‘000m3/day 1,206 694 512

1,230 702 528

1248 724 524

No. of NEWater plants - 3 3 4

Sale of NEWater ‘000m3/day 73 81 134

Sale of Industrial Water ‘000m3/day 107 112 80

Volume of used water treated ‘000m3/day 1,352 1399 1469

Water Demand Unit 2005 2006 2007

Domestic water consumption per capita litres/day 160 158 157

(MEWR, pg 7, 2008)106

Singapore has developed the Four National Taps or four water

sources to ensure a sustainable and diversified water supply for Singapore.

These comprise of local catchment water, imported water, NEWater and

desalination. (MEWR, 2008)106


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i) Local Catchment Water

Singapore practises large scale rainwater harvesting from protected,

unprotected and urbanised catchments. This is made possible by

integrated land-use planning and development, including siting of pollutive

industries in designated zones, strict pollution control and a comprehensive

separate sewerage and drainage systems. There are currently 14 reservoirs

in Singapore, but two-thirds of Singapore’s land surface will be water

catchment by 2011 with the completion of the Marina Barrage and Punggol-

Serangoon Reservoir Scheme as shown in Figure 19. The reservoirs are

integrated with excess water collected from one reservoir pumped into

another for storage to reduce water wastage under the reservoir integration

scheme.

(Lee P.O., 2005)107

Figure 19 Singapore's catchment areas

PUB is working on the Marina Barrage project, which is a unique 3-in-1

project. The barrage is a dam across the 350m Marina Channel and

comprises of nine steel crest gates. The benefits of the Marina barrage are

to act as a tidal barrier to control flooding in some of the low-lying parts in

the city, create the 15th freshwater reservoir with a catchment area of 100 sq

km in the already built-up city centre of Singapore, and to become a major

Punggol‐


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Dissertation 2008

lifestyle attraction with many opportunities for lifestyle, recreational and

sports activities in downtown Singapore. (Lee P.O. 2005)107

ii) Imported Water

Singapore currently imports water from the neighbouring Malaysian

state of Johor under two long term agreements signed in 1961 and 1962.

These agreements allow Singapore an entitlement of raw water until 2011

and 2061 respectively. The water is treated in Johor and transferred via

three large pipelines across the 2km causeway between the two countries.

(Tortajada C., 2006)91

iii) NEWater

All used water in Singapore is collected via the sewerage systems and

treated at water reclamation plants to international standards. The use of

advanced water technology allows Singapore to reclaim the treated used

water. This ultra-clean NEWater is treated using a multi-barrier micro-

filtration, reverse osmosis and ultra-violet disinfection. The technology is

discussed in Table 3 of Chapter 3.2. Although a small percentage is

mixed into the raw water reservoirs for indirect potable use (IPU), most of

the NEWater is supplied for use in the industries and commercial buildings

as part of a substitution strategy. This meant that potable water, previously

used by the industries, can now be available for human consumption. PUB

owns and operates 3 NEWater factories, and purchase NEWater from the

Keppel Seghers Ulu Pandan NEWater Plant on a 20 years Design, Built,

Own & Operate (DBOO) contract, which can supply up to 148, 000 m3/day

(32 MGD or million gallons per day). (PUB, 2008)108

PUB (2008)109 also recently signed a 25-year NEWater agreement with

Sembcorp Utilities Pte Ltd to design, build, own and operate the 50 MGD

NEWater plant on the rooftop of the new PUB’s Changi Water Reclamation

Plant. As with all NEWater factories, PUB will put in place a

comprehensive system of water quality tests and audit, and the plant’s

online water quality monitoring system will be linked to PUB for


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continuous real-time monitoring. The 5 NEWater factories will supply up

to 30% of Singapore’s current water needs by 2010.

iv) Desalination

The first Public-Private-Partnership project in Singapore is the

desalination plant project awarded to Singspring Pte ltd, a subsidiary of

Hyflux Ltd. PUB can purchase desalinated water from the 30 MGD

(136,380 m3/day) Singspring Desalination Plant for 20 years. A 2-pass

reverse osmosis process, with pre-treatment (Dissolved Air Flotation

Filtration) and post-treatment (remineralisation) processes, produces

desalinated water to supply up to 10% of Singapore’s current water needs.

The desalinated water is blended with PUB’s treated potable water before

being supplied to the public. The plant was officially opened by Prime

Minister Lee Hsien Loong on 13 Sep 05 and the project was accorded the

Asia Pacific Water Deal of the year 2003 by Euromoney. As the plant’s

online monitoring system is linked to PUB’s monitoring system, PUB is

able to monitor the major water quality parameters on a continuous, real-

time basis.

(Hyflux, 2008)110

There are 14 integrated water supply zones in Singapore, comprising

the distribution network from each of the 14 service reservoirs determined

both by hydraulics and reservoir capacity, rather than by population size. This

is because the supply zones serve both industry and domestic needs. These

service reservoirs, consisting of one or more tanks, are regularly maintained

and are shut down for inspection and cleaning at least once every 5 years or as

and when necessary. (Haja N., 2008)111

Kok T.W. et al (2008)112 highlighted that PUB has a comprehensive

integrated water quality management and operation system to monitor water

quality for the water supply chain from source to tap. This allows real-time

analysis and trending of water quality, which is used in operations and

decision making. Woo C.H. (2008)113 explained that any abnormality will be


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generated by the systems, which will alert the relevant officers to take

necessary action.

Together with monitoring of source water quality and operational water

quality at the water treatment works, the water quality is also monitored

extensively throughout the water supply network through:

• Online water quality monitoring of surrogate parameters using

onsite sensors and analysers located at strategic critical control points;

• Daily routine sampling of about 170 samples collected at all service

reservoirs, distribution mains, customers’ premises and specific

sampling programme from schools and hospitals;

• Toxicity monitoring using telemetric CCTV fish monitoring in

conventional tanks or Fish Biosensors using de-chlorinated treated

water from critical points along the trunk mains and service reservoirs.

(Kok T.W., 2008)112

With regards to water quality management within the customer’s

premises, Kok T.W. et al (2008)112 explained that PUB employs the following

three-prong approach:

• Legislation & enforcement – only PUB licensed plumbers can

carry out plumbing works, and all plumbing works and fittings have to

comply with the stipulated requirements. Customers are required to

regularly inspect and properly maintain their water services

installations.

• Education – regular briefings and circulars are used to raise

awareness and provide help to customers in maintaining their water

services installations.

• Physical measures – Advice on physical measures to ensure water

quality is provided for customers.


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7. Discussion

The UN has started to recognise that safe drinking water and sanitation

are very important elements for supporting a country’s development. This can

be seen in the targeted approach to solving global issues through the

provisions of the MDGs, and the involvement of the various UN agencies,

countries and other organisations in assisting those countries which are facing

water shortages. Other than investment in technological developments, there

is a need to ensure that there are sufficient supporting institutional

arrangements for educational, legislative and regulatory structure to support

the sustainable developments of the country. While technology provides the

means to solve the micro issues, such as removing a certain contaminant from

drinking water, the institutional and supporting arrangements provide a

sustainable solution to the macro issues.

Without proper access to safe and sustainable drinking water and

sanitation for its population, a country’s developments can be severely limited.

In the case of Singapore, drinking water is essential for both human and

economic survival. The provision of a stable government and sustainable and

reliable infrastructure (including amongst other things, uninterrupted,

reliable drinking water supply and 100% sanitation services) ensure continued

foreign investment in providing jobs and development of Singapore’s growth

as a nation. This makes Singapore attractive as a regional headquarters for

many multi-national companies looking to invest and develop their businesses

in the Asia-Pacific region. It can be appreciated that the development of

Singapore’s integrated water resources management systems has taken time

to continuously develop and maintain, ensuring its high standards today.

While governments are usually committed to providing safe drinking

water for the population, there is uncertainty as to what determines that

drinking water is safe. It is not possible to determine whether water is safe

unless it is tested and measured against a set of parameters regularly. The

challenge is that there are both natural (which was previously unknown) and

man-made (previously not available) contaminants that can be found in water


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that needs to be treated to potable standards. Unless there is sufficient

evidence to show the safe contaminant concentration levels, the setting of

acceptable standards is determined by a government authority’s judgement,

based on perceived health, social and economic considerations. Monitoring

and sampling programmes require resources, which have to be balanced with

other necessary developments. As monitoring programmes usually provide

long term intangible results, they are given less priority than other short term

tangible developments.

Countries, in different regions and in different stages of development,

face different issues in relation to drinking water quality. The development of

regional groupings, like the EU and ASEAN, provides common grounds for

networking and sharing of knowledge on common water quality issues,

ensuring consistent policies among the regional member states in providing a

minimum level of safe drinking water in the region. With a regional minimum

safe drinking water level, it would allow the region to raise the safe drinking

water quality level in a sustainable, continuous manner. Raising the safe

drinking water quality level requires time, commitment and resources, and

has to be consistent with the developments in other areas in the country.

7.1. International guidelines

As an international health authority, the WHO is able to pull resources

together to provide public health advice to the WHO member states. This

allows the cross-sharing of knowledge in determining and handling known

public health risks. The WHO Guidelines for Drinking Water Quality is the

result of water experts around the world collaborating on producing

recommendations for the provision of safe drinking water. The guideline

values for the parameters stated in the Guidelines are the minimum standards

that all countries could aspire to achieve in their national drinking water

quality standards.

Being an international advisory document, the guidelines have to be

comprehensive and have to cater for all situations, whether in developed or


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developing communities. It is up to the national authorities to determine the

application of the guidelines. The success of implementing the framework for

safe drinking water depends on the political will, government stability and the

institutional arrangements within the country.

The government leaders must have the political will to ensure that

water remains one of their top priorities, so that the necessary resources can

be committed to developing and maintaining the drinking water

infrastructures to meet the national requirements. This can be seen in the

case of Singapore, where there is political will in ensuring that water remains

a priority on the national agenda. Together with scientific evidence, the

political will of the leaders in accepting and promoting NEWater is also one of

the main reasons that NEWater is generally accepted by the public as one of

Singapore’s national taps, allowing reclaimed water to be used nationwide.

Drinking water and sanitation infrastructure require resources to

support both development and maintenance. This is only possible if there is

stability in the country with a government committed to providing the

necessary climate and support for investments. There is a need to ensure that

the private or public water utilities can recover the cost and that sufficient

incentives are provided to allow private water utilities to consider investing in

water services in the country. It is unlikely that a company will provide

services and invest in an unstable country, where there is no regular and

effective collection of sufficient tariffs to at least cover the cost of the water

services and generate some profit.

The WSP is only a tool to ensure that the health-based targets are

achieved. It is for the national health authority to determine what targets are

required to be achieved based on the local conditions, as highlighted in

Chapter 4.1.2. The WSP will not be effective without a proper definition in

the legislation defining “drinking water quality”.

Although the WSP is a simple tool, there is a need to determine the

necessary institutional arrangement that will allow the sustainable


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implementation of the WSP. One of the institutional arrangements is the

legislative instrument to require the use of WSPs in water services.

As highlighted by Deere et al (2007) on page - 63 -in chapter 6.2,

feedback from the WDP trainers indicated that there is a need to include WSP

in the legislation to ensure that water utilities give it priority. The UK and

Singapore are some of the few countries which have specifically amended their

legislation to ensure that water utilities implement WSPs. However, there is a

parallel need for an independent regulator who must be competent enough to

verify that the WSP is implemented effectively.

Existing well-managed water utilities have already been practising the

hazard analysis and critical control mentioned in the WSP, especially in the

water treatment works and distribution systems. The WSP allows water

utilities to involve other stakeholders to put in place WSP in the catchment

and consumer’s premises, which are usually outside the control of the water

utilities.

The WHO has recommended shifting the emphasis for the provision of

safe drinking water to a preventive approach instead of relying on end-point

monitoring. End-point monitoring is now used as a verification tool to ensure

that the WSP is implemented properly. As such, the sampling frequency is

very minimal, as seen in Table 6 & Table 7. The Guidelines do recommend a

higher sampling frequency for variable surface water sources. This is

necessary, as sampling only provides water quality information at the point of

collection. There is definitely a need to monitor water quality regularly and

frequently to ensure a safe drinking water supply. It is important to take into

account water quality changes due to the local (seasonal, geological, cultural,

industrial, etc) conditions.

7.2. EU & ASEAN perspectives

It can be seen from analysing the EU and the ASEAN that the 2 regional

groups function quite differently. There are also political, cultural and social

differences. While both regional groups were formed for the common


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economic and social development of their region, the approaches to achieving

these objectives are quite different. The EU has created an independent EU

government that presides over the member states and as such, can create

legislation to govern and push regional objectives. However, the ASEAN has

to ensure that ASEAN objectives do not constitute interference in the internal

affairs of member states and functions mainly through consensus.

The ASEAN therefore does not have the legislative authority to allow

the creation of regulations similar to the EU DWD to ensure a minimum water

quality among the ASEAN region. It would be more useful for the ASEAN to

provide guidance, advice and resources through the ASEAN working groups,

as shown in Figure 15, to share resources on water quality management. A

regional grouping of water quality regulators, affiliated to the WHOROE’s

International Network of Water Regulators (of which the Singapore water

quality regulator is a member of) could be set up to allow the sharing of

knowledge and networking among the ASEAN water quality regulators.

It can be seen that there is a shift in the population in Southeast Asian

countries and the ASEAN cities are growing. As highlighted by Tortajada C.

(2006)91, Singapore’s experience and performance in integrated water

resources managements could be emulated by other countries to ensure

sustainable water supplies for their urban cities. However, to cater to the

entire country, Singapore’s experiences have to be adapted to each city in the

country, and expanded to the surrounding rural communities. The key is then

to ensure that there are suitable institutional arrangements to allow for such

developments.

7.3. UK and Singapore water quality regulatory model

While the UK has adopted a privatised industry in England & Wales,

with independent regulators to allow for private investments to meet the EU

DWD, Singapore has elected for public agencies to provide water and

sewerage services, with the provision for public-private partnership in water

treatment. Both drinking water industries are funded by the collection of


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tariffs, which is based on a set of criteria to allow the UK water companies and

the Singapore water agencies to be sufficiently financed. Subsidies are

provided separately by the governments, and not by the companies and

utilities. This allows a fairer payment of water services, both for the

consumers and the water utilities.

In the UK, the water quality is governed by legislation, strictly enforced

by the DWI. The water utilities are self-regulated, as they provide the

necessary sampling results to show compliance with the regulatory

requirements. The legislation requires the compliance of the relevant

parameters at specified concentration values and the water companies are

only obliged to supply such information. The water companies will not

sample, test and provide information to the DWI on parameters that are not

required by the regulations. As such, there is a need to ensure that the

legislation caters for all possible parameters and situations. It is thus crucial

to have the DWI monitoring and ensuring that the companies are carrying out

their obligations and to introduce changes to the legislation when required.

The collection of monthly water quality data allows the DWI to analyse and

determine contraventions and possible trends, so that further contraventions

can (hopefully) be avoided.

The UK water quality regulatory model, with the DWI functioning as an

independent water quality regulator, is a cost effective model. The model

allows the water utilities to carry out monitoring programmes, ensure

compliance with the water quality standards, and carry out improvement

programmes and remedial actions for water quality incidents. Water utilities

would then be able to gain competencies in handling water quality issues in

their provision of services. At the same time, it allows the government to focus

on being regulators, rather than service providers. The regulators exist as a

check to ensure compliance, while the water utilities focus on operational

efficiency and cost recovery through tariffs.

The DWI is well established with more than 18 years of regulatory

experience, which shows that a strong regulator within a well defined


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regulatory structure is required for ensuring that there are improvements to

water quality. It is important to the DWI that they are seen to be acting

independently from the UK government and without interference from

political leaders, especially since the DWI is funded through DEFRA. This is

to assure the public that their interests are being protected. This

independence can be seen in the heavy reliance of science-based evidence

used in decision making within the DWI and the sharing of water quality

information with the public through media releases and the annual reports by

the Chief Inspector. This would certainly apply to both public and private

utilities.

In Singapore’s case, PUB is responsible for the provision of drinking

water of the highest quality to the public, and reports directly to the Minister

for Environment and Water Resources in discharging its duties. PUB is also

considered self-regulated, although there is a difference from the term used in

the UK. This is because the legislations do not provide an exact meaning to

the definition of water quality. As drinking water is of high importance in

Singapore, PUB has to take extra measures to determine and ensure safe

drinking water based on the guideline values recommended by the WHO

Guidelines for safe drinking water.

The move to introduce the Environmental Public Health (Quality of

Piped Drinking Water) Regulations 2008, with the requirements of the use of

WSP and water quality parameters, and the setting up of the Drinking Water

Unit within the NEA are important steps to ensuring the continued provision

of safe drinking water within Singapore.

As the DWU is a relatively new setup within the Environmental Health

Department of the NEA, the functions of the DWU are still being worked out

so that there is no conflict between the functions of PUB and NEA. It is likely

that PUB will remain responsible for the technical and efficient operation of

water services, while DWU is responsible for ensuring that public health risks

arising from drinking water are minimised.


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It would certainly be useful for the DWU to develop capabilities similiar

to those of the DWI, to allow the DWU to carry out its roles and functions

competently. This is because of the need for competent knowledge in public

health risks, water treatment processes, water quality issues, legislation and

local conditions to allow the DWU to carry out the regulatory duties effectively.

Other than the approval of WSPs, the DWU would have to carry out

technical audits to verify that the water suppliers are implementing the

approved WSPs appropriately. This would require the setting up of a

technical audit framework that allows the DWU to carry out regular

assessment and checks to assure themselves and the public that the risks are

being managed properly.

The development of a water quality database and proper procedures in

the submission of water quality data would allow the DWU to carry out

evidence-based decision making and water quality assessment, and also to

carry out a risk-based approach to auditing water supplies, focusing their

limited resources on high risk parts of the water supply systems. The DWU

would have up-to-date water quality information for the entire country

available, thus allowing the DWU to investigate and determine current and

potential water quality issues.

All the WHO Guidelines parameters have been adopted as the water

quality parameters in the regulations, some of which might not be applicable

in Singapore. This has meant that additional resources are used in potentially

unnecessary sampling and monitoring. It is reasonable for the legislation to

allow the water companies and utilities to carry out testing of all of the water

quality parameters for a period of time, to effectively determine which

relevant parameters should be monitored. The DWU could analyse the water

quality data to refine the water quality parameters in the regulations and

independently determine the relevant water quality parameters to be

monitored more frequently.

The legislation does not clearly specify the functions of the DWU, the

actions and procedures to be carried out in the event of a breach in the


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drinking water standards, nor the penalty or enforcement actions for such

breaches. As such, it is unclear what the DWU or the Director-General of

Public Health will do in the event of such breaches. It would likely include

notices to the water suppliers to carry out remedial actions to ensure that such

contraventions would not happen again. It is also not a requirement in the

legislation to inform the DWU of water quality incidents, which means that

the DWU will be unable to investigate all incidents, thereby ensuring that the

water companies are carrying out proper remedial actions.

An independent regulator with sufficient authority is crucial in

providing an independent check on the drinking water quality and ensuring

that water utilities implement suitable improvement programmes to meet

regulatory compliance. Although both PUB and NEA report to the same

ministry, it is highly certain that there is independence in regulating water

quality, as PUB & NEA are separate entities with separate funding.

7.4. Proposed ASEAN Water Quality Regulatory Model

Arising from the studies, a flexible basic water quality regulatory model

for ASEAN cities is proposed, as shown in Figure 20.

The model is divided into three sections: International; Regional/Sub-

regional and National arrangements. The purpose of the model is to provide

the basic regulatory framework to ensure adequacy and sufficiency of an

uninterrupted supply of safe drinking water.

The UN agencies and the WHO form the international arrangements, in

the form of co-ordinators and advisors for the region and countries in

ensuring safe drinking water. The UN could focus on international co-

operation, development and implementation of strategies to achieve the

MDGs for the regions. The WHO provides advice and support on public

health risks arising from drinking water. The international bodies would have

broad global overviews of the critical health issues and could coordinate

resources in assisting countries dealing with drinking water issues.


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Figure 20 Proposed basic water industry model

Intern

ational

Accredited Laboratories

ASEAN (Regional co-ordinator and advisor)

National Environment Ministry

United Nations (International Co-ordinator & Support)

WHO (International Health Authority & Advisor)

Regulatory Agencies Ψ Water Quality Regulator

Public Water Agency

Public Statutory Water Supply

companies

Public Owned works

Private Water works

Public Statutory Supplier works

Public Water Agency Distribution Network

Public Statutory Supplier distribution

network

Private Water Supplier

Ж – Consumer Representative group Ψ – Regulatory agencies include the financial regulator, environment agencies,

land use/town planning authorities, accreditation authority, and local authorities/councils

Consumer

Public owned drainage and

reservoir system

ж ж ж

Nation

al R

egional &

S

ub

-regional

ASEAN Network of Water Regulators


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In Southeast Asia, the ASEAN could continue to play an active role in

ensuring and promoting safe drinking water in the agenda. The formation of

the ASEAN Network of Water Regulators, affiliated with the International

Network of Water Regulators, will allow the ASEAN regulators to share and

collaborate on water regulatory challenges and water quality issues pertaining

to the region. An ASEAN agency could also be instituted to develop the

reporting system for a common set of water quality standard and parameters

across the ASEAN for evaluation and analysis.

Within the country, the national Environment Ministry could be

responsible for policies and legislation on water resources and quality. The

ministry could introduce and maintain suitable institutional arrangement and

legislative authority to regulate water resources and water services. This

allows the Environment Ministry to exercise a national overview of the water

challenges of the country and coordinate the developments needed. The

country could look at every practicable source of water and develop an

integrated water resources management strategy to ensure sustainable water

resources for the population and for national developments. The IWRM

strategy must be consistent with the developments of the country.

Most ASEAN countries already have public water agencies in place to

provide water services. This could be developed further to practice IWRM and

carry out the operational functions of IWRM for the Environment Ministry.

The public water agency could be responsible for the water resources and

sanitation infrastructure, including the rivers, lakes, reservoirs, drainage

systems and sewerage collection systems. The public water agency or the

environment agency could also be responsible for abstraction and discharge

into the water resources infrastructure to ensure the sufficient use of water

resources and that the water resources are not heavily polluted.

The water quality regulator could be one of the independent regulators

set up to ensure drinking water quality. The other regulators could include

land-use authority, accreditation authorities, financial regulator, environment

agencies and local councils/governments. The water quality regulator ensures


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that the safe drinking water is supplied in accordance with the regulations by

carrying out similar functions like the DWI as discussed in Chapter 4.3.3.

Water supply services would be provided by three different types of

entities, which are the public water agency, public statutory water supply

companies and private water supplies.

The public water agency could operate its own water treatment works

to gain operational experience and maintain a basic water supply, and could

also enter into public-private-partnership agreements to purchase treated

water from treatment works owned and operated by private companies. The

public agency would still be responsible for the distribution network and

supply to the consumers.

Private water companies could also be licensed to be public statutory

water supply companies, which could have separate water supply systems to

consumers. There could also be connections in the separate distribution

networks to ensure continuity of supply and need only be used in rare

circumstances.

In certain areas, there might be a need to maintain and allow for

private water supplies. However, these should be the exception, rather than

the norm, as private water supplies will usually be used in places which are

beyond the reach (both economic and physical conditions) of the public water

supply networks.

There should also be feedback channels, including consumer

representatives groups to allow for feedback and complaints to the water

suppliers. Such complaints are usually the first indications of water quality

and sufficiency issues.

The basic water quality model will allow a consistent approach to

developing and ensuring that there is an uninterrupted supply of safe drinking

water to the public. It is also flexible enough to be adapted to the local

conditions in the country.


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7.5. Metaldehyde-containing pesticides, a practical

issue

Metaldehyde is one of the emerging contaminants that UK water

utilities are required to deal with in their treatment systems. The main issue

is that water utilities are finding that GAC and ozone might not be efficient in

removing metaldehyde from drinking water and thus there might be a risk

that this might contravene the pesticide standards. There is also no accredited

approach for analysing metaldehyde in water. Analytical results from the case

studies raised many questions as the data does not seem to make sense,

especially since some of the final treated water samples have higher

metaldehyde concentration than that found in the raw water sample. As with

all contaminants, there is a need for a multi-faceted approach to involve

stakeholders in resolving the issue.

It can be clearly seen from the studies of the metaldehyde incidents that

the sampling programmes were extended to monitor for the presence of

metaldehyde, due to the information sharing amongst the water companies

and with the DWI. This was in addition to having the DWI as an independent

regulator to audit the water companies on their monitoring programmes and

regulatory compliance.


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8. Conclusion

While technologies are available to treat water to a suitable quality and can

be adopted by countries to provide safe drinking water, technologies focus

on the micro issues. Regulatory and management frameworks focus on the

macro policies and issues to ensure the sustainable use of technology in

providing safe drinking water for the population. Technology and

regulatory frameworks need to be incorporated concurrently to ensure a

consistent approach to ensure a sustainable water supply for the

population’s basic needs and national developments.

Regulations are not meant to deter or hinder water utilities in discharging

their duties. It is meant to help water utilities (both public and private) in

ensuring that they are providing the best possible water services to the

public. Regulations also ensure that both the interests of the water utilities

and the consumer are protected. Well-managed utilities would have

already carried out the necessary checks to ensure compliance and

incorporated possible strategies to handle potential issues in their water

services. The water quality regulators independently verify regulatory

compliance and assure the public that the water utilities are providing safe

drinking water. At the same time, this arrangement allows the water

quality regulators to obtain and analyse information on current and

potential water issues.

The WHO Guidelines for drinking water quality provide a framework that

could be adapted to different countries and situations in different stages of

development to ensure the provision of safe drinking water. The

institutional arrangements within the region and country are important

factors to ensure that the framework is properly implemented. One of the

important criteria in the implementation would be to amend the

legislation to require the water utilities to implement WSPs. Although the

emphasis is on a preventive approach to safe drinking water, there is a

need to balance the approach with regular and sufficiently frequent


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monitoring programmes. There is no assurance of water quality unless

there is evidence through proper sampling and analysis of water samples.

The effective UK water quality model has advantages in that it allows the

government to focus on being regulators, rather than service providers. It

has a regulatory framework with a strong independent water quality

regulator that has been proven to be effective in ensuring that safe

drinking water is provided through regulatory compliance. It is also cost

effective, as it allows water utilities to be self-regulated and provide for

sampling and monitoring of compliance parameters with no need for

duplicating resources in a parallel sampling and monitoring programme

operated by a regulator or health ministry.

The ASEAN has seen a shift in the populations from rural communities to

urban cities. This meant that there is a critical need to ensure that there

are sufficient and adequate safe drinking water supplies for these rapidly

growing cities. It is important that the ASEAN ensures that member

countries review and enact the relevant water policies and legislation, as

well as develop ASEAN water quality standards. There are certainly great

potential and advantages in adapting the UK regulatory model for the

ASEAN cities. ASEAN member countries could also emulate Singapore’s

success in integrated water resources management. These led to the

development of the water quality regulatory model in Figure 20.

Singapore has successfully implemented water resources management and

has been focusing on technology development. The government has just

started on developing a regulatory framework for drinking water quality.

The introduction of the new regulations in Singapore and the DWU are

positive steps in aligning with the WHO Guidelines on drinking water

quality and in ensuring the sustainable development of safe drinking water

in the country. As the DWU is a relatively new regulatory unit, it would be

useful to collaborate with the DWI to develop its competencies in a unique

Singaporean model. To discharge its duties, some of the possible areas in

which the DWU can develop to strengthen its competencies and knowledge

are to:


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Set up water quality database for water quality analysis;

Develop frameworks for technical audits and incident investigations;

Refine the Singapore water quality standards and tighten the water

quality legislation;

Focus research on emerging water quality issues; and

Provide continual training for staff in water treatment, water quality

and public health issues required in carrying out their regulatory

functions.

Metaldehyde contaminant is an emerging cause of concern in the UK.

Water utilities are finding that their current treatment processes do not

seem to be effective in removing metaldehyde. Sampling and analytical

approaches need to be developed to ensure the timely and accurate

detection of metaldehyde in water. These studies indicate that the UK

water quality regulatory structure and the presence of the DWI have

ensured that water companies are working to monitor and resolve the

metaldehyde issue and other contraventions in a consistent manner.

The dissertation focuses only on water quality regulatory models and has

only covered the tip of the iceberg of the challenges faced in the provision

of a sustainable, uninterrupted and safe drinking water supply to the

ASEAN cities. Some potential areas of further studies are the:

Further development and implementation of the ASEAN water quality

regulatory model, taking into consideration the local conditions within

the ASEAN member countries;

Development of a training framework for competent regulators;

Review and tighten the Singapore water quality legislations;

Identification of the institutional arrangements required for the

implementation of the WHO framework for safe drinking water; and

Development of strategies for the effective treatment and control of

metaldehyde in drinking water.

~ End ~


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Appendix A - The UN Millennium Development Goals

(Lenton R. et al, pp xviii – xix, 2005)2

Goals Target

1. Eradicate Extreme poverty & hunger

1. Halve, between 1990 & 2015, the proportion of people whose income is less than $1 a day.

2. Halve, between 1990 & 2015, the proportion of people who suffer from hunger.

2. Achieve universal Primary Education

3. Ensure that by 2015, children everywhere, boys and girls alike, will be able to complete a full course of primary schooling.

3. Promote gender equality and empower women

4. Eliminate gender disparity in primary and secondary education, preferably by 2005, and in all levels of education by 2015.

4. Reduce child mortality

5. Reduce by two-thirds, between 1990 and 2015, the under-5 mortality rate.

5. Improve maternal health

6. Reduce by three-quarter, between 1990 and 2015, the maternal mortality rate.

6. Combat HIV/AIDS, malaria and other diseases

7. Have halted by 2015 and begun to reverse the spread of HIV/AIDS

8. Have halted by 2015 and begun to reverse the incidence of malaria and other major diseases.

7. Ensure Environmental sustainability

9. Integrate the principles of sustainable development into country policies and programmes and reverse the loss of environmental resources.

10. Halve, by 2015, the proportion of people without sustainable access to safe drinking water and basic sanitation.

11. Have achieved by 2020 a significant improvement

in the lives of at least 100 million slum dwellers


Christopher Chua


Dissertation 2008

8. Develop a global partnership for development

12. Develop further an open, rule-based, predictable, non-discriminatory trading and financial system (includes a commitment to good governance, development and poverty reduction - both nationally and internationally)

13. Address the special needs of the Least Developed Countries (include tariff- and quota-free access for Least Developed Countries’ export, enhanced programme of debt relief for heavily indebted poor countries (HIPC) and cancellation of official bilateral debt and more generous official development assistance of countries committed to poverty reduction)

14. Address the special needs of landlocked countries

and small island developing states (through the Programme of Action for Sustainable Development of Small Island Developing States and 22nd General Assembly provision)

15. Deal comprehensively with the debt problems of

developing countries through national and international measures in order to make debt sustainable in the long term

16. In cooperation with developing countries, develop

and implement strategies for decent and productive work for youth

17. In cooperation with pharmaceutical companies,

provide access to affordable essential drugs in developing countries

18. In cooperation with the private sector, make

available the benefits of new technologies, especially Information and Communication Technologies


Christopher Chua


Dissertation 2008

Appendix B – International Drinking Water Guidelines

Appendix B-1: The WHO Guidelines for safe drinking water

(WHO, 2006)7

Guideline values for verification of microbial quality a

Organisms Guideline value

All water directly intended for drinking

E. coli or Thermotolerant coliform bacteria b,c Must not be detectable in any 100-ml sample

Treated water entering the distribution system

E. coli or Thermotolerant coliform bacteria b Must not be detectable in any 100-ml sample

Treated water in the distribution system

E. coli or Thermotolerant coliform bacteria b Must not be detectable in any 100-ml sample

a. Immediate investigative action must be taken if E. coli is detected.

b. Although E. coli is the more precise indicator of faecal pollution, the count of Thermotolerant coliform bacteria is an acceptable alternative. If necessary, proper confirmatory tests must be carried out. Total coliform bacteria are not acceptable indicators of the sanitary quality of water supplies, particularly in tropical areas, where many bacteria of no sanitary significance occur in almost all untreated supplies.

c. It is recognized that in the great majority of rural water supplies, especially in developing countries, faecal contamination is widespread. Especially under these conditions, medium-term targets for the progressive improvement of water supplies should be set.

Guideline values for chemicals that are of health significance in

drinking-water

Chemical Guideline value a (mg/litre)

Remarks

Acrylamide 0.0005b

Alachlor 0.02b

Aldicarb 0.01 Applies to aldicarb sulfoxide and aldicarb sulfone

Aldrin and dieldrin 0.00003 For combined aldrin plus dieldrin

Antimony 0.02

Arsenic 0.01 (P)

Atrazine 0.002

Barium 0.7

Benzene 0.01b

Benzo[a]pyrene 0.0007b


Christopher Chua


Dissertation 2008


Remarks

Boron 0.5 (T)

Bromate 0.01b(A,T)

Bromodichloromethane 0.06b

Bromoform 0.1

Cadmium 0.003

Carbofuran 0.007

Carbon tetrachloride 0.004

Chlorate 0.7 (D)

Chlordane 0.0002

Chlorine 5 (C) For effective disinfection, there should be a residual concentration of free chlorine of >0.5 mg/litre after at least 30 min contact time at pH <8.0

Chlorite 0.7 (D)

Chloroform 0.3

Chlorotoluron 0.03

Chlorpyrifos 0.03

Chromium 0.05 (P) For total chromium

Copper 2 Staining of laundry and sanitary ware may occur below guideline value

Cyanazine 0.0006

Cyanide 0.07

Cyanogen chloride 0.07 For cyanide as total cyanogenic compounds

2,4-D (2,4-dichlorophenoxyacetic acid)

0.03 Applies to free acid

2,4-DB 0.09

DDT and metabolites 0.001

Di(2-ethylhexyl)phthalate 0.008

Dibromoacetonitrile 0.07

Dibromochloromethane 0.1

1,2-Dibromo-3-chloropropane 0.001b

1,2-Dibromoethane 0.0004b (P)

Dichloroacetate 0.05b (T, D)

Dichloroacetonitrile 0.02 (P)

Dichlorobenzene, 1,2- 1 (C)

Dichlorobenzene, 1,4- 0.3 (C)

Dichloroethane, 1,2- 0.03b


Christopher Chua


Dissertation 2008


Remarks

Dichloroethene, 1,2- 0.05

Dichloromethane 0.02

1,2-Dichloropropane (1,2-DCP) 0.04 (P)

1,3-Dichloropropene 0.02b

Dichlorprop 0.1

Dimethoate 0.006

Dioxane, 1,4- 0.05b

Edetic acid (EDTA) 0.6 Applies to the free acid

Endrin 0.0006

Epichlorohydrin 0.0004 (P)

Ethyl benzene 0.3 (C)

Fenoprop 0.009

Fluoride 1.5 Volume of water consumed and intake from other sources should be considered when setting national standards

Hexachlorobutadiene 0.0006

Isoproturon 0.009

Lead 0.01

Lindane 0.002

Manganese 0.4 (C)

MCPA 0.002

Mecoprop 0.01

Mercury 0.006 For inorganic mercury

Methoxychlor 0.02

Metolachlor 0.01

Microcystin-LR 0.001 (P) For total microcystin-LR (free plus cell- bound)

Molinate 0.006

Molybdenum 0.07

Monochloramine 3

Monochloroacetate 0.02

Nickel 0.07

Nitrate (as NO3-) 50 Short-term exposure

Nitrilotriacetic acid (NTA) 0.2

Nitrite (as NO2-) 3 Short-term exposure

0.2 (P) Long-term exposure


Christopher Chua


Dissertation 2008


Remarks

Pendimethalin 0.02

Pentachlorophenol 0.009b (P)

Permethrin 0.3 Only when used as a larvicide for public health purposes

Pyriproxyfen 0.3

Selenium 0.01

Simazine 0.002

Styrene 0.02 (C)

2,4,5-T 0.009

Terbuthylazine 0.007

Tetrachloroethene 0.04

Toluene 0.7 (C)

Trichloroacetate 0.2

Trichloroethene 0.02 (P)

Trichlorophenol, 2,4,6- 0.2b (C)

Trifluralin 0.02

Trihalomethanes The sum of the ratio of the concentration of each to its respective guideline value should not exceed 1

Uranium 0.015 (P,T) Only chemical aspects of uranium addressed

Vinyl chloride 0.0003b

Xylenes 0.5 (C)

a. P = provisional guideline value, as there is evidence of a hazard, but the available information on health effects is limited; T = provisional guideline value because calculated guideline value is below the level that can be achieved through practical treatment methods, source protection, etc.; A = provisional guideline value because calculated guideline value is below the achievable quantification level; D = provisional guideline value because disinfection is likely to result in the guideline value being exceeded; C = concentrations of the substance at or below the health-based guideline value may affect the appearance, taste or odour of the water, leading to consumer complaints.

b. For substances that are considered to be carcinogenic, the guideline value is the concentration in drinking-water associated with an upper-bound excess lifetime cancer risk of 10-5 (one additional cancer per 100 000 of the population ingesting drinking-water containing the substance at the guideline value for 70 years). Concentrations associated with upper-bound estimated excess lifetime cancer risks of 10-4 and 10-6 can be calculated by multiplying and dividing, respectively, the guideline value by 10.


Christopher Chua


Dissertation 2008

Guidance levels for radionuclide in drinking-water

Radionuclide Guidance level

(Bq/litre)a


(Bq/litre)a


(Bq/litre)a

3H 10 000 93Mo 100 140La 100

7Be 10000 99Mo 100 139Ce 1000

14C 100 96Tc 100 141Ce 100

22Na 100 97Tc 1000 143Ce 100

32P 100 97mTc 100 144Ce 10

33P 1 000 99Tc 100 143Pr 100

35S 100 97Ru 1000 147Nd 100

36Cl 100 103Ru 100 147Pm 1000

45Ca 100 106Ru 10 149Pm 100

47Ca 100 105Rh 1000 151Sm 1000

46Sc 100 103Pd 1000 153Sm 100

47Sc 100 105Ag 100 152Eu 100

48Sc 100 110mAg 100 154Eu 100

48V 100 111Ag 100 155Eu 1000

51Cr 10000 109Cd 100 153Gd 1000

52Mn 100 115Cd 100 160Tb 100

53Mn 10 000 115mCd 100 169Er 1000

54Mn 100 111In 1000 171Tm 1000

55Fe 1 000 114mIn 100 175Yb 1000

59Fe 100 113Sn 100 182Ta 100

56Co 100 125Sn 100 181W 1000

57Co 1 000 122Sb 100 185W 1000

58Co 100 124Sb 100 186Re 100

60Co 100 125Sb 100 185Os 100

59Ni 1000 123mTe 100 191Os 100

63Ni 1000 127Te 1000 193Os 100

65Zn 100 127mTe 100 190Ir 100

71Ge 10 000 129Te 1000 192Ir 100

73As 1 000 129mTe 100 191Pt 1000

74As 100 131Te 1000 193mPt 1000

76As 100 131mTe 100 198Au 100

77As 1 000 132Te 100 199Au 1000

75Se 100 125I 10 197Hg 1000


Christopher Chua


Dissertation 2008


(Bq/litre)a


(Bq/litre)a


(Bq/litre)a

82Br 100 126I 10 203Hg 100

86Rb 100 129I 1000 200Tl 1000

85Sr 100 131I 10 201Tl 1000

89Sr 100 129Cs 1000 202Tl 1000

90Sr 10 131Cs 1000 204Tl 100

90Y 100 132Cs 100 203Pb 1000

91Y 100 134Cs 10 206Bi 100

93Zr 100 135Cs 100 207Bi 100

95Zr 100 136Cs 100 210Bib 100

93mNb 1000 137Cs 10 210Pbb 0.1

94Nb 100 131Ba 1000 210Pob 0.1

95Nb 100 140Ba 100 223Rab 1

224Rab 1 235Ub 1 242Cm 10

225Ra 1 236Ub 1 243Cm 1

226Rab 1 237U 100 244Cm 1

228Rab 0.1 238Ub,c 10 245Cm 1

227Thb 10 237Np 1 246Cm 1

228Thb 1 239Np 100 247Cm 1

229Th 0.1 236Pu 1 248Cm 0.1

230Thb 1 237Pu 1000 249Bk 100

231Thb 1 000 238Pu 1 246Cf 100

232Thb 1 239Pu 1 248Cf 10

234Thb 100 240Pu 1 249Cf 1

230Pa 100 241Pu 10 250Cf 1

231Pab 0.1 242Pu 1 251Cf 1

233Pa 100 244Pu 1 252Cf 1

230U 1 241Am 1 253Cf 100

231U 1 000 242Am 1000 254Cf 1

232U 1 242mAm 1 253Es 10

233U 1 243Am 1 254Es 10

234Ub 10 254mEs 100

a. Guidance levels are rounded according to averaging the log scale values (to 10n if the calculated value was below 3 × 10n and above 3 × 10n-1).

b. Natural radionuclide.

c. The provisional guideline value for uranium in drinking-water is 15 mg/litre based on its chemical toxicity for the kidney


Christopher Chua


Dissertation 2008

Minimum frequency of sampling and analysis of water supplies (WHO, pp 54, 1997)26

Source and mode of supply

Minimum frequency of sampling and analysis

Remarks

Bacteriological Physical/chemical

Open wells for community supply

Sanitary protection measures; bacteriological testing only if situation demands

Once initially for community wells

Pollution usually expected to occur

Covered dug wells and shallow tube wells with hand-pumps


Once initially, thereafter as situation demands

Situations requiring testing: change in environmental conditions, outbreak of waterborne disease, or increase in incidence of waterborne diseases

Deep tube wells with hand-pumps




Protected springs Once initially, thereafter as situation demands

Periodically for residual chlorine if water is chlorinated


Community rainwater collection systems


Not needed -

Piped distribution system (up to 100 000 population)

12 Faecal indicator test sample per year per 5000 population rounded up

1 per 5000 population

Piped distribution system (100 000 – 500 000 population)

12 Faecal indicator test sample per year per 10000 population plus additional 120 samples

1 per 10 000 population, plus 10 additional samples

Piped distribution system (>500 000 population)

12 Faecal indicator test sample per year per 10000 population plus additional 180 samples

1 per 10 000 population, plus 10 additional samples


Christopher Chua


Dissertation 2008

Appendix B-2: Analysis of Microbial water quality

OECD & WHO (pp48 - 73, 2003)9 provided an analysis of microbial and non-microbial parameters which are used to assess drinking water quality.

Microbial parameters include:

a) Total coliform – Basic information on source water quality, it is easy to detect and enumerate in water, include non faecal coliform. Detectable using simple inexpensive cultural method

b) Thermotolerant coliform – Refers to a group of total coliform able to ferment lactose at 44 - 45○C and comprises genus Escherichia, Klebsiella, Enterobacter & Citrobacter. Total coliform can originate from faeces, industrial effluent. It is easily detectable.

c) E. coli – taxonomically well defined; abundant in faeces concentration of 109 per gram. Detectable by simple inexpensive cultural methods.

d) Enterococci & faecal streptococci – mostly of faecal origin and generally regarded as specific indices of human faecal pollution. Faecal streptococci is more resistant to stress and chlorination. Enterococci can be used to supplement E.coli in catchment assessment in tropical climates as an index of faecal pollution and can also be an additional indicator of treatment efficiency. Detectable by simple inexpensive cultural methods

e) Ratio of counts of Thermotolerant and faecal streptococci – >4 indicate a human source while <0.7 indicate animal source. Not recommended as means of differentiating pollution

f) Direct total counts and activity tests (total and viable bacteria) – provide basic info on no of bacteria in water during abstraction and treatment. Not used in routine monitoring as the test assesses only general microbial levels and not faecal contamination. Simple and rapid.

g) Heterotrophic aerobic and aerobix spore former bacterial counts – used to assess general bacterial content of water (only those able to grow and produce visible colonies on media under prescribed temp and incubation time. Useful for long term assessment of water treatment efficiency and cleanliness & integrity of distribution system and suitability of water for use in food & drink manufacture. Simple, inexpensive cultural methods.

h) Bacteriophages – viruses that infect bacteria; easy to detect and enumerate. Coliphages is detectable by simple, inexpensive and rapid methods, while Bacteroides bacteriophages require anaerobic culture facilities & more expertise and lab resources

Somatic Coliphages – infect host-specific strain via cell walls (somatic) receptors and frequently detected in human and animal faeces. Normal host is E. coli. Somatic coliphages occurs very likely to be related to faecal pollution. However inadequate knowledge of their natural history limit usefulness. Suitable index of faecal contamination in raw water and treatment virus inactivation and removal

F-specific RNA bacteriophages (male-specific coliphages) – infect bacteria through F- or sex-pili. Commonly found in huge number in sewage. Has relatively high persistence and similarity to viruses, it is a primary index


Christopher Chua


Dissertation 2008

for sewage contamination, treatment efficiency or groundwater protection. Possible to distinguish human from animal contamination by grouping F-specific RNA coliphages. 2 groups of RNA and DNA containing F-specific coliphages; 4 basic sub-group of F-specific RNA coliphages (similar in size, shape and basic composition to many human enteric viruses)

Bateroides phages – outnumber coliform group in human faeces with Bacteroide fragilis most commonly found more resistant to natural inactivation and water treatment processes that bacterial indicators an decay rate similar to human enteric viruses. However, low densities in raw water and currently unreliable methods of detection

i) Sulphite-reducing clostridia & clostridium perfingens – C. perfingens is faecally specific and is preferred. Clostridia not recommended for routine monitoring because of their longer length of survival (false alarm). C. perfingens without E. coli in groundwater indicate intermittent contamination. Presence in finished water indicates deficiencies in treatment filtration processes and potential for protozoan cysts to have passed through treatment process.

j) Pseudomonas aeruginosa and aeromonas spp. – environmentally widespread. Ps. Aeruginosa commonly found in faeces, soil, water and sewage, but multiply in enriched aquatic environment and on organic material surface in contact with water. Aeromonas spp. can be found in treated distribution mains because of regrowth. Both are useful for assessing regrowth in distribution. Detectable by simple, inexpensive cultural methods. Considered as health risk to laboratory staff, as both are pathogenic

k) Presence-absence test (P-A) – the most probable number method reduced to a single tube, indicates if coliform bacteria are present or not. Effective screening device for occasional contamination. Very simple to tests. Standard procedure in APHA, AWWA, WEF

l) Hydrogen sulphide test – some bacteria associated with faecal contamination produce H2S. H2S strip test is potentially useful for screening water sources and drinking water for faecal contamination without access to water testing lab, or a simple advanced warning system.

m) Pathogens – detecting actual risks of infections rather than potential indicator. However, it is impossible to monitor all known pathogens and other unknown pathogenic agents

Enteric viruses – always associated with human and animal faecal pollution. Can survive for long periods in environment and quite resistant to treatment. Enumeration is expensive and time consuming. Most cannot be grown in laboratory condition. Requires well-equipped lab and highly trained staff

Protozoan parasites (Cryptosporidium oocysts and Giardia cysts) – variable number found in faeces in human and animal sources including amphibians, birds and mammals. Long survival in environment and very resistant to treatment. Isolation and enumeration is expensive and requires well equipped lab.


Christopher Chua


Dissertation 2008

Non-microbial parameters include: a) Rainfall events – major cause of degradation of source water quality as

rainfall drives pathogen and soil into and through water bodies, resuspend sediments, infiltrate groundwater and cause overflow in combined and poorly maintained sewers.

b) Flow – determines availability and production of quality water. Flow affects discharge volumes, coagulation & sedimentation processes and disinfection efficiencies

c) Colour – denotes presence of humic and fulvic substances, metal and highly coloured industrial waste in water; and reflects degradation of source water, corrosion problem in distribution system and performance in adsorptive treatment processes like GAC. Simple and cheaply measured on site

d) pH – affects treatment processes. Simple and inexpensive testing methods which can be online or in-situ.

e) Solids – amount of total, suspended and dissolved solids in water affect removal and disinfection processes, as well as taste and appearance of drinking water. In-situ or online tests are generally inexpensive and fast.

f) Turbidity – measure of light refracted by suspended solids in water, and is the most widely used general application non-microbial parameters which provide significant data on treatment processes. Relatively inexpensive and fast in-situ or online tests are available.

g) Particle size analysis – general index of removal effectiveness and a good quality parameter for filtration. However, online tests are expensive and require a high level of skill

h) Microscopic particulate analysis – provide microscopic information on the nature of particulates in water. More for research and investigation, rather than for routine monitoring. Test is generally not available as it is time-consuming and requires well-trained skilled personnel.

i) Disinfectant residual concentration – primary data on quality control of disinfection.

j) Organic matter – indicates potential of heterotrophic bacteria regrowth in reservoirs and distribution systems. Measured as Total Organic Carbon (TOC), Chemical Oxygen Demand (COD) or Biochemical Oxygen demand (BOD). Tests can be carried out with basic laboratory facilities and adequately trained personnel. TOC tests, which are applicable to drinking water, can be carried out using online instrumentation.

k) Specific chemical parameters like Ammonia or Boron – Relatively simple and rapid in-field ammonia tests could be used as initial detection of fresh sanitary waste contamination. Boron is proposed as an index of faecal pollution, but is limited, as use of boron as a water softener in detergents is widely being discontinued. Further research, well-equipped laboratories and well-trained staff are required for other proposed index chemical parameters like faecal sterols, secretory immunogolobulin type A and urobilin.


Christopher Chua


Dissertation 2008

Appendix B-3: Acceptability water quality

(WHO, 2006)7

Biologically derived contaminants

Actinomycetes & fungi Abundant in surface water sources and can grow on unsuitable materials in the distribution network; give rise to geosmin, 2-methyl isoborneol and other substances

Animal life Invertebrate animals can be present in raw water sources and can pass through the inadequate processes in water treatment works and reside in the distribution system. Can also act as secondary hosts to parasites

Cynobacteria and algae Algae blooms may impede coagulation and filtration processes, causing colour and turbidity issues in treated water. Can give rise to geosmin, 2-methyl isoborneol and other chemicals and can induce cyanotoxins in drinking water, which is of public health significance

Iron bacteria Causes oxidation of ferrous and manganese salts, leaving deposits

Chemically derived contaminants

Aluminium Aluminium in excess of 0.1-0.2 mg/l results in aluminium hydroxide floc in distribution system and iron discolouration

Ammonia Threshold odour concentration of ammonia at alkaline pH is about 1.5mg/l and a taste threshold of about 35 mg/l

Chloride High concentrations give salty taste. The taste threshold is about 200 – 300mg/l for sodium, potassium and calcium chloride.

Chlorine Detectable at concentrations even at 0.3 mg/l to below 5mg/l. Taste threshold is about 0.6 – 1.0mg/l

Chlorophenols Very low taste and odour thresholds. Taste thresholds for 2-chlorophenols, 2,4-dichlorophenols and 2,4,6-trichlorphenols are 0.1, 0.3 and 2mg/l. Odour thresholds are 10, 40 and 300µg/l respectively.

Colour Primarily due to the presence of humic and fulvic acids (organic matter). Colour levels are detectable above 15 true colour units

Copper Mainly arises from water leaching copper from copper pipes and can vary significantly with length of contact with the pipes. Staining occurs at copper concentration of 1 mg/l, and imparts colour and bitter taste at 5mg/l

Dichlorobenzenes Odour thresholds for 1,2- and 1,4-dichlorobenzene are at 2-10 & 0.3 – 30 mg/l respectively. Tastes thresholds are 1 and 6 mg/l respectively.

Dissolved Oxygen (DO) Reduction in DO in water can lead to an increase in ferrous iron concentration, causing subsequent discolouration at the tap when the water is aerated

Ethyl benzene Odour threshold is about 2 - 130µg/l, while the taste threshold is 72 - 200µg/l

Hardness Taste threshold for calcium causing hardness is about 100-300 mg/l, while that for magnesium is likely to be much lower

Hydrogen sulphide Taste and odour threshold is about 0.05 – 0.1 mg/l Iron Promotes the growth of iron bacteria. At concentrations of 0.3

mg/l, iron causes staining and imparts taste


Christopher Chua


Dissertation 2008

Manganese Concentrations above 0.1 mg/l, manganese causes undesirable tastes and cause staining.

Monochloramine Monochloramine is formed when chlorine reacts with ammonia in water, and can be detected at 0.3 mg/l.

Petroleum oils Low molecular weight hydrocarbon with low odour thresholds can occur in water due to petroleum oils.

pH pH is an important operational control parameter for treatment processes efficiency, although it has no direct impact on customer. Low pH water can corrode water mains and pipes in household water systems, which can have an adverse impact on taste and appearance.

Sodium Taste threshold is about 200 mg/l and depends on the associated anions and temperature of water

Styrene Styrene’s sweet odour could be detected in water at 4- 2600µg/l.

Sulfate The noticeable taste of Sodium & Calcium Sulfate can be detected at 250 mg/l and 1000 mg/l respectively.

Toulene The sweet, pungent, benzene-like odour of Toulene can be detected at 24 - 170µg/l. The reported taste threshold is 40 -120µg/l

Total Dissolved Solids (TDS)

High TDS causes scaling in water pipes, heaters, boilers and household appliances. The taste threshold of TDS is at 600 mg/l

Trichlorobenzenes The odour-threshold for 1,2,3-, 1,2,4-, 1,3,5-trichlorobenzene are 10, 5-30 and 50µg/l.

Turbidity Turbidity less than 5 NTU is usually acceptable. Xylene Concentrations at 300µg/l will give rise to detectable taste and

odour. The guideline value for xylene is based on the lowest odour threshold of 20µg/l

Zinc Concentrations at 4mg/l will impart an undesirable astringent tastes. Concentrations of 3-5mg/l will cause water to appear opalescent and greasy film appears on boiling.


Christopher Chua


Dissertation 2008

Appendix C – EU Drinking Water Regulations

Appendix C-1: Drinking Water Directive (PARAMETERS AND PARAMETRIC VALUES)

(EC Council, 1998)31 PART A - Microbiological parameters

Parameter Parametric value (number/100 ml)

Escherichia coli (E. coli) 0

Enterococci 0

The following applies to water offered for sale in bottles or containers:

Parameter Parametric value

Escherichia coli (E. coli) 0/250 ml

Enterococci 0/250 ml

Pseudomonas aeruginosa 0/250 ml

Colony count 22 °C 100/ml

Colony count 37 °C 20/ml

PART B - Chemical parameters

Parameter Parametric value Unit Notes

Acrylamide 0.10 µg/l Note 1

Antimony 5.0 µg/l

Arsenic 10 µg/l

Benzene 1.0 µg/l

Benzo(a)pyrene 0.010 µg/l

Boron 1.0 mg/l

Bromate 10 µg/l Note 2

Cadmium 5.0 µg/l

Chromium 50 µg/l

Copper 2.0 mg/l Note 3

Cyanide 50 µg/l

1,2-dichloroethane 3.0 µg/l

Epichlorohydrin 0.10 µg/l Note 1

Fluoride 1.5 mg/l

Lead 10 µg/l Notes 3 and 4


Christopher Chua


Dissertation 2008


Mercury 1.0 µg/l

Nickel 20 µg/l Note 3

Nitrate 50 mg/l Note 5

Nitrite 0.50 mg/l Note 5

Pesticides 0.10 µg/l Notes 6 and 7

Pesticides — Total 0.50 µg/l Notes 6 and 8

Polycyclic aromatic hydrocarbons

0.10 µg/l Sum of concentrations of specified compounds; Note 9

Selenium 10 µg/l

Tetrachloroethene and Trichloroethene

10 µg/l Sum of concentrations of specified parameters

Trihalomethanes — Total

100 µg/l Sum of concentrations of specified compounds; Note 10

Vinyl chloride 0.50 µg/l Note 1 Note 1: The parametric value refers to the residual monomer concentration in the water as calculated according to

specifications of the maximum release from the corresponding polymer in contact with the water. Note 2: Where possible, without compromising disinfection, Member States should strive for a lower value. For the

water referred to in Article 6(1)(a), (b) and (d), the value must be met, at the latest, 10 calendar years after the entry into force of the Directive. The parametric value for bromate from five years after the entry into force of this Directive until 10 years after its entry into force is 25 µg/l.

Note 3: The value applies to a sample of water intended for human consumption obtained by an adequate sampling method (1) at the tap and taken so as to be representative of a weekly average value ingested by consumers. Where appropriate the sampling and monitoring methods must be applied in a harmonised fashion to be drawn up in accordance with Article 7(4). Member States must take account of the occurrence of peak levels that may cause adverse effects on human health.

Note 4: For water referred to in Article 6(1)(a), (b) and (d), the value must be met, at the latest, 15 calendar years after the entry into force of this Directive. The parametric value for lead from five years after the entry into force of this Directive until 15 years after its entry into force is 25 µg/l. Member States must ensure that all appropriate measures are taken to reduce the concentration of lead in water intended for human consumption as much as possible during the period needed to achieve compliance with the parametric value. When implementing the measures to achieve compliance with that value Member States must progressively give priority where lead concentrations in water intended for human consumption are highest.

Note 5: Member States must ensure that the condition that [nitrate]/50 + [nitrite]/3 # 1, the square brackets signifying the concentrations in mg/l for nitrate (NO3) and nitrite (NO2), is complied with and that the value of 0,10 mg/l for nitrites is complied with ex water treatment works.

Note 6: ‘Pesticides’ means: organic insecticides, organic herbicides, organic fungicides, organic nematocides, organic acaricides, organic algicides, organic rodenticides organic slimicides, related products (inter alia, growth regulators) and their relevant metabolites, degradation and reaction products. Only those pesticides which are likely to be present in a given supply need be monitored.

Note 7: The parametric value applies to each individual pesticide. In the case of aldrin, dieldrin, heptachlor and heptachlor epoxide the parametric value is 0,030 µg/l.

Note 8: ‘Pesticides — Total’ means the sum of all individual pesticides detected and quantified in the monitoring procedure.

Note 9: The specified compounds are: benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(ghi)perylene, indeno(1,2,3-cd)pyrene.

Note 10: Where possible, without compromising disinfection, Member States should strive for a lower value. The specified compounds are: chloroform, bromoform, dibromochloromethane, and bromodichlorome-thane. For the water referred to in Article 6(1)(a), (b) and (d), the value must be met, at the latest, 10 calendar years after the entry into force of this Directive. The parametric value for total THMs from five years after the entry into force of this Directive until 10 years after its entry into force is 150 µg/l. (1) To be added following the outcome of the study currently being carried out. Member States must ensure that all appropriate measures are taken to reduce the concentration of THMs in water intended for human consumption as much as possible during the period needed to achieve compliance with the parametric value. When implementing the measures to achieve this value, Member States must progressively give priority to those areas where THM concentrations in water intended for human consumption are highest.


Christopher Chua


Dissertation 2008

PART C - Indicator Parameters


Aluminium 200 µg/l

Ammonium 0,50 mg/l

Chloride 250 mg/l Note 1

Clostridium perfringens (including spores)

0 number/100 ml Note 2

Colour Acceptable to consumers and no abnormal change

Conductivity 2 500 µS cm-1 at 20 °C Note 1

Hydrogen ion concentration 6.5 and 9.5 pH units Notes 1 and 3

Iron 200 µg/l

Manganese 50 µg/l

Odour Acceptable to consumers and no abnormal change

Oxidisability 5,0 mg/l O2 Note 4

Sulphate 250

mg/l Note 1

Sodium 200 mg/l

Taste Acceptable to consumers and no abnormal change

Colony count 22° No abnormal change

Coliform bacteria 0 number/100 ml Note 5

Total organic carbon (TOC) No abnormal change Note 6

Turbidity Acceptable to consumers and no abnormal change

Note 7

Tritium 100 Bq/l Notes 8 and 10

Total indicative dose 0.10 mSv/year Notes 9 and 10

Note 1: The water should not be aggressive.

Note 2: This parameter need not be measured unless the water originates from or is influenced by surface water. In the event of non-compliance with this parametric value, the Member State concerned must investigate the supply to ensure that there is no potential danger to human health arising from the presence of pathogenic micro-organisms, e.g. Cryptosporidium. Member States must include the results of all such investigations in the reports they must submit under Article 13(2).

Note 3: For still water put into bottles or containers, the minimum value may be reduced to 4,5 pH units.

For water put into bottles or containers which is naturally rich in or artificially enriched with carbon dioxide, the minimum value may be lower.

Note 4: This parameter need not be measured if the parameter TOC is analysed.

Note 5: For water put into bottles or containers the unit is number/250 ml.

Note 6: This parameter need not be measured for supplies of less than 10 000 m³ a day.


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Note 7: In the case of surface water treatment, Member States should strive for a parametric value not exceeding 1.0 NTU (nephelometric turbidity units) in the water ex treatment works.

Note 8: Monitoring frequencies to be set later in Annex II.

Note 9: Excluding tritium, potassium -40, radon and radon decay products; monitoring frequencies, monitoring methods and the most relevant locations for monitoring points to be set later in Annex II.

Note 10: 1. The proposals required by Note 8 on monitoring frequencies, and Note 9 on monitoring frequencies, monitoring methods and the most relevant locations for monitoring points in Annex II shall be adopted in accordance with the procedure laid down in Article 12. When elaborating these proposals the Commission shall take into account inter alia the relevant provisions under existing legislation or appropriate monitoring programmes including monitoring results as derived from them. The Commission shall submit these proposals at the latest within 18 months following the date referred to in Article 18 of the Directive.

2. A Member State is not required to monitor drinking water for tritium or radioactivity to establish total indicative dose where it is satisfied that, on the basis of other monitoring carried out, the levels of tritium of the calculated total indicative dose are well below the parametric value. In that case, it shall communicate the grounds for its decision to the Commission, including the results of this other monitoring carried out.


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Appendix C-2: Drinking Water Directive (MONITORING) TABLE A: Parameters to be analysed 1. Check monitoring The purpose of check monitoring is regularly to provide information on the organoleptic and microbiological quality of the water supplied for human consumption as well as information on the effectiveness of drinking-water treatment (particularly of disinfection) where it is used, in order to determine whether or not water intended for human consumption complies with the relevant parametric values laid down in this Directive. The following parameters must be subject to check monitoring. Member States may add other parameters to this list if they deem it appropriate. Aluminium (Note 1) Ammonium Colour Conductivity Clostridium perfringens (including spores) (Note 2) Escherichia coli (E. coli) Hydrogen ion concentration Iron (Note 1) Nitrite (Note 3) Odour Pseudomonas aeruginosa (Note 4) Taste Colony count 22 °C and 37 °C (Note 4) Coliform bacteria Turbidity

Note 1: Necessary only when used as flocculant (*).

Note 2: Necessary only if the water originates from or is influenced by surface water (*).

Note 3: Necessary only when chloramination is used as a disinfectant (*).

Note 4: Necessary only in the case of water offered for sale in bottles or containers.

(*) In all other cases, the parameters are in the list for audit monitoring.

2. Audit monitoring The purpose of audit monitoring is to provide the information necessary to determine whether or not all of the Directive's parametric values are being complied with. All parameters set in accordance with Article 5(2) and (3) must be subject to audit monitoring unless it can be established by the competent authorities, for a period of time to be determined by them, that a parameter is not likely to be present in a given supply in concentrations which could lead to the risk of a breach of the relevant parametric value. This paragraph does not apply to the parameters for radioactivity, which, subject to Notes 8, 9 and 10 in Annex I, Part C, will be monitored in accordance with monitoring requirements adopted under Article 12.


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TABLE B1: Minimum frequency of sampling and analyses for water intended for human consumption supplied from a distribution network or from a tanker or used in a food-production undertaking Member States must take samples at the points of compliance as defined in Article 6(1) to ensure that water intended for human consumption meets the requirements of the Directive. However, in the case of a distribution network, a Member State may take samples within the supply zone or at the treatment works for particular parameters if it can be demonstrated that there would be no adverse change to the measured value of the parameters concerned.

Volume of water distributed or produced each day within a supply zone (Notes 1 and 2)

m³

Check monitoring number of samples per year (Notes 3, 4 and 5)

Audit monitoring number of samples per year (Notes 3 and

5)

≤100 (Note 6) (Note 6)

>100 ≤1 000 4 1

>1 000 ≤10 000 1 + 1 for each 3 300 m³/d and part thereof of the total volume

>10 000 ≤100 000 4 + 3 for each 1 000 m³/d and part thereof of the total volume

3 + 1 for each 10 000 m³/d and part thereof of the total volume

>100 000 10 + 1 for each 25 000 m³/d and part thereof of the total volume

Note 1: A supply zone is a geographically defined area within which water intended for human consumption comes from one or more sources and within which water quality may be considered as being approximately uniform.

Note 2: The volumes are calculated as averages taken over a calendar year. A Member State may use the number of inhabitants in a supply zone instead of the volume of water to determine the minimum frequency, assuming a water consumption of 200 l/day/capita

Note 3: In the event of intermittent short-term supply the monitoring frequency of water distributed by tankers is to be decided by the Member State concerned.

Note 4: For the different parameters in Annex I, a Member State may reduce the number of samples specified in the table if: (a) the values of the results obtained from samples taken during a period of at least two

successive years are constant and significantly better than the limits laid down in Annex I, and

(b) no factor is likely to cause a deterioration of the quality of the water. The lowest frequency applied must not be less than 50 % of the number of samples specified in the table except in the particular case of note 6.

Note 5: As far as possible, the number of samples should be distributed equally in time and location.

Note 6: The frequency is to be decided by the Member State concerned.


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TABLE B2: Minimum frequency of sampling and analysis for water put into bottles or containers intended for sale

Volume of water produced for offering for sale in bottles

or containers each day (1) m³

Check monitoring number of samples per year

Audit monitoring number of samples per year

≤10 1 1

>10 ≤60 12 1

>60 1 for each 5 m³ and part thereof of the total volume

1 for each 100 m³ and part thereof of the total volume

(1) The volumes are calculated as averages taken over a calendar year.


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Appendix C-3: Drinking Water Directive (SPECIFICATIONS FOR THE ANALYSIS OF PARAMETERS)

Each Member State must ensure that any laboratory at which samples are analysed has a system of analytical quality control that is subject from time to time to checking by a person who is not under the control of the laboratory and who is approved by the competent authority for that purpose. 1. PARAMETERS FOR WHICH METHODS OF ANALYSIS ARE SPECIFIED

The following principles for methods of microbiological parameters are given

either for reference whenever a CEN/ISO method is given or for guidance, pending the possible future adoption, in accordance with the procedure laid down in Article 12, of further CEN/ISO international methods for these parameters. Member States may use alternative methods, providing the provisions of Article 7(5) are met.

Coliform bacteria and Escherichia coli (E. coli) (ISO 9308-1) Enterococci (ISO 7899-2) Pseudomonas aeruginosa (prEN ISO 12780) Enumeration of culturable microorganisms - Colony count 22 °C (prEN ISO 6222) Enumeration of culturable microorganisms - Colony count 37 °C (prEN ISO 6222) Clostridium perfringens (including spores) Membrane filtration followed by anaerobic incubation of the membrane on m-CP agar (Note 1) at 44 ± 1 °C for 21 ± 3 hours. Count opaque yellow colonies that turn pink or red after exposure to ammonium hydroxide vapours for 20 to 30 seconds. Note 1: The composition of m-CP agar is:

Basal medium

Tryptose (30 g) Yeast extract (20 g) Sucrose(5 g)

L-cysteine hydrochloride (1 g) MgSO4 · 7H2O (0,1 g) Bromocresol purple (40 mg)

Agar (15 g) Water (1 000 ml)

Dissolve the ingredients of the basal medium, adjust pH to 7,6 and autoclave at 121 °C for 15 minutes. Allow the medium to cool and add:

D-cycloserine 400 mg

Polymyxine-B sulphate 25 mg

Indoxyl-β-D-glucoside to be dissolved in 8 ml sterile water before addition

60 mg

Filter — sterilised 0,5% phenolphthalein diphosphate solution 20 ml

Filter — sterilised 4,5 % FeCl3·6H2O 2 ml

2. PARAMETERS FOR WHICH PERFORMANCE CHARACTERISTICS ARE SPECIFIED 2.1. For the following parameters, the specified performance characteristics are that

the method of analysis used must, as a minimum, be capable of measuring concentrations equal to the parametric value with trueness, precision and limit of detection specified. Whatever the sensitivity of the method of analysis used,


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the result must be expressed using at least the same number of decimals as for the parametric value considered in Annex I, Parts B and C.

Parameters Trueness % of parametric

value (Note 1)

Precision % of parametric

value (Note 2)

Limit of detection % of

parametric value (Note 3)

Conditions Notes

Acrylamide To be controlled by product specification

Aluminium 10 10 10

Ammonium 10 10 10

Antimony 25 25 25

Arsenic 10 10 10

Benzo(a)pyrene 25 25 25

Benzene 25 25 25

Boron 10 10 10

Bromate 25 25 25

Cadmium 10 10 10

Chloride 10 10 10

Chromium 10 10 10

Conductivity 10 10 10

Copper 10 10 10

Cyanide 10 10 10 Note 4

1,2-dichloroethane 25 25 10

Epichlorohydrin To be controlled by product specification

Fluoride 10 10 10

Iron 10 10 10

Lead 10 10 10

Manganese 10 10 10

Mercury 20 10 20

Nickel 10 10 10

Nitrate 10 10 10

Nitrite 10 10 10

Oxidisability 25 25 10 Note 5

Pesticides 25 25 25 Note 6

Polycyclic aromatic hydrocarbons

25 25 25 Note 7


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Parameters Trueness % of parametric

value (Note 1)

Precision % of parametric

value (Note 2)

Limit of detection % of

parametric value (Note 3)

Conditions Notes

Selenium 10 10 10

Sodium 10 10 10

Sulphate 10 10 10

Tetrachloroethene 25 25 10 Note 8

Trichloroethene 25 25 10 Note 8

Trihalomethanes — Total

25 25 10 Note 7

Vinyl chloride To be controlled by product specification

Note 1(1*): Trueness is the systematic error and is the difference between the mean value of the large number of repeated measurements and the true value.

Note 2 (2*): Precision is the random error and is usually expressed as the standard deviation (within and between batches) of the spread of results about the mean. Acceptable precision is twice the relative standard deviation.

Note 3: Limit of detection is either: - three times the relative within batch standard deviation of a natural sample containing a low concentration of the parameter, or - five times the relative within batch standard deviation of a blank sample.

Note 4: The method should determine total cyanide in all forms.

Note 5: Oxidation should be carried out for 10 minutes at 100 °C under acid conditions using permanganate.

Note 6: The performance characteristics apply to each individual pesticide and will depend on the pesticide concerned. The limit of detection may not be achievable for all pesticides at present, but Member States should strive to achieve this standard.

Note 7: The performance characteristics apply to the individual substances specified at 25 % of the parametric value in Annex I.

Note 8: The performance characteristics apply to the individual substances specified at 50 % of the parametric value in Annex I.

2.2. For hydrogen ion concentration the specified performance characteristics are that the method of analysis used must be capable of measuring concentrations equal to the parametric value with a trueness of 0.2 pH units and a precision of 0.2 pH units.

3. PARAMETERS FOR WHICH NO METHOD OF ANALYSIS IS SPECIFIED Colour Odour Taste Total organic carbon Turbidity (Note 1)

Note 1: For turbidity monitoring in treated surface water the specified performance characteristics are that the method of analysis used must, as a minimum, be capable of measuring concentrations equal to the parametric value with a trueness of 25 %, precision of 25 % and a 25 % limit of detection. (1*) These terms are further defined in ISO 5725.


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Appendix D – Drinking Water Regulations in UK

The Water Supply (Water Quality) Regulations 2000

(UK Parliament, 2000)38

PRESCRIBED CONCENTRATIONS AND VALUES

TABLE A – MICROBIOLOGICAL PARAMETERS

Part I: Directive requirements

Item Parameters Concentration or Value (maximum)

Units of Measurement

Point of compliance

1. Enterococci 0 number/100ml Consumers’ taps 2. Escherichia coli

(E. coli) 0 number/100ml Consumers’ taps

Part II: National requirements



Point of compliance

1. Coliform bacteria 0 number/100ml Service reservoirs(*) and water treatment works

2. Escherichia coli (E. coli)

0 number/100ml Service reservoirs and water treatment works

(*)Compliance required as to 95% of samples from each service reservoir (regulation 4(6)).

TABLE B – CHEMICAL PARAMETERS

Part I: Directive requirements



Point of compliance

1. Acrylamide 0.10 µg/l (i) 2. Antimony 5.0 µgSb/l Consumers’ taps 3. Arsenic 10 µgAs/l Consumers’ taps 4. Benzene 1.0 µg/l Consumers’ taps 5. Benzo(a)pyrene 0.010 µg/l Consumers’ taps 6. Boron 1.0 mgB/l Consumers’ taps 7. Bromate 10 µgBrO3/l Consumers’ taps 8. Cadmium 5.0 µgCd/l Consumers’ taps 9. Chromium 50 µgCr/l Consumers’ taps 10. Copper(ii) 2.0 mgCu/l Consumers’ taps 11. Cyanide 50 µgCN/l Consumers’ taps 12. 1, 2 dichloroethane 3.0 µg/l Consumers’ taps 13. Epichlorohydrin 0.10 µg/l (i) 14. Fluoride 1.5 mgF/l Consumers’ taps 15. Lead(ii) (a) 25, from 25th

December 2003 until immediately before 25th December 2013 (b) 10, on and after 25th December 2013

µgPb/l Consumers’ taps

16. Mercury 1.0 µgHg/l Consumers’ taps 17. Nickel(ii) 20 µgNi/l Consumers’ taps 18. Nitrate(iii) 50 mgNO3/l Consumers’ taps


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19. Nitrite(iii) 0.50 0.10

mgNO2/l Consumers’ taps Treatment works

20. Pesticides(iv)(v) Aldrin _ Dieldrin _ Heptachlor _ Heptachlor epoxide _ other pesticides

0.030

0.10

µg/l µg/l

Consumers’ taps Consumers’ taps

21. Pesticides: Total(vi) 0.50 µg/l Consumers’ taps 22. Polycyclic aromatic

hydrocarbon(vii) 0.10 µg/l Consumers’ taps

23. Selenium 10 µgSe/l Consumers’ taps 24. Tetrachloroethene and

Trichloroethene(viii) 10 µg/l Consumers’ taps

25. Trihalomethanes: Total(ix)

100 µg/l Consumers’ taps

26. Vinyl chloride 0.50 µg/l (i) (i) The parametric value refers to the residual monomer concentration in the water as calculated according to specifications of the maximum release from the corresponding polymer in contact with the water. This is controlled by product specification. (ii) See also regulation 6(6). (iii) See also regulation 4(2)(d). (iv) See the definition of “pesticides and related products” in regulation 2. (v) The parametric value applies to each individual pesticide. (vi) “Pesticides: Total” means the sum of the concentrations of the individual pesticides detected and quantified in the monitoring procedure. (vii) The specified compounds are benzo(b)fluoranthene; benzo(k)fluoranthene; benzo(ghi)perylene & indeno(1,2,3-cd)pyrene. The parametric value applies to the sum of the concentrations of the individual compounds detected and quantified in the monitoring process. (viii) The parametric value applies to the sum of the concentrations of the individual compounds detected and quantified in the monitoring process. (ix) The specified compounds are chloroform; bromoform; dibromochloromethane; and bromodichloromethane. The parametric value applies to the sum of the concentrations of the individual compounds detected and quantified in the monitoring process.

Part II: National requirements



Point of compliance

1. Aluminium 200 µgAl/l Consumers’ taps 2. Colour 20 mg/l Pt/Co Consumers’ taps 3. Hydrogen ion 9.5

6.5 (minimum) pH value pH value

Consumers’ taps

4. Iron 200 µgFe/l Consumers’ taps 5. Manganese 50 µgMn/l Consumers’ taps 6. Odour Acceptable to consumers and no abnormal

change Consumers’ taps

7. Sodium 200 mgNa/l Consumers’ taps 8. Taste Acceptable to consumers and no abnormal

change Consumers’ taps

9. Tetrachloromethane 3 µg/l Consumers’ taps 10. Turbidity 4 NTU Consumers’ taps


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INDICATOR PARAMETERS

Item Parameters Specification Concentration or Value

(maximum unless otherwise stated) or State


Point of monitoring

1. Ammonium 0.50 mgNH4/l Consumers’ taps 2. Chloride

(i) 250 mgCl/l Supply point

(*)

3. Clostridium perfringens (including spores)

0 Number/100ml Supply point(*)

4. Coliform bacteria 0 Number/100ml Consumers’ taps 5. Colony counts No abnormal change Number/1ml at

22°C Number/1ml at 37°C

Consumers’ taps, service reservoirs and treatment works

6. Conductivity(i)

2500 µS/cm at 20°C Supply point(*)

6A. Hydrogen ion 9.5

6.5 (minimum) pH value pH value

Consumers’ taps

7. Sulphate(i)

250 mgSO4/l Supply point(*)

8. Total indicative dose (for

radioactivity)(ii)

0.10 mSv/ year Supply point(*)

9. Total organic carbon (TOC)

No abnormal change mgC/l Supply point(*)

10. Tritium (for radioactivity)

100 Bq/l Supply point(*)

11. Turbidity 1 NTU Treatment works (i) The water should not be aggressive. (ii) Excluding tritium, potassium – 40, radon and radon decay products. (*) May be monitored from samples of water leaving treatment works or other supply point, as no significant change during distribution.


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MONITORING

TABLE 1- PARAMETERS AND CIRCUMSTANCES FOR CHECK MONITORING

(1) Item

(2) Parameter

(3) Circumstances

1. Aluminium When used as flocculant or where the water originates from, or is influenced by, surface waters

2. Ammonium 3. Clostridium perfringens

(including spores) Where the water originates from, or is influenced by, surface waters

4. Coliform bacteria 4A. Colony counts 5. Colour 6. Conductivity 7. Escherichia coli (E. coli) 8. Hydrogen ion 9. Iron When used as flocculant or where the water originates from,

or is influenced by, surface waters 10. Manganese Where the water originates from, or is influenced by, surface

waters 11. Nitrate When chloramination is practised 12. Nitrite When chloramination is practised 13. Odour 14. Taste 15. Turbidity

TABLE 2- ANNUAL SAMPLING FREQUENCIES: WATER SUPPLY ZONES

(1) Substances and parameters subject to

check monitoring

(2) Estimated population

of water supply zone

(3) Reduced

(4) Standard

E. coli Coliform bacteria Residual disinfectant Aluminium Ammonium Clostridium Perfringens (including

spores)(*)

< 100 ≥ 100

4 12 per 5,000

population(i)

Colony counts Colour

Conductivity(*)

Hydrogen ion Iron Manganese

Nitrate(ii)

Nitrite(ii)

Odour Taste Turbidity

<100 100–4,999

5,000–9,999 10,000–29,999 30,000–49,999 50,000–79,999

80,000–100,000

1 2 6

12 18 26 38

2 4

12 24 36 52 76


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(1) Substances and parameters subject to

Audit monitoring

(2) Estimated population

of water supply zone

(3) Reduced

(4) Standard

Aluminium Antimony Arsenic

Benzene(*)

Benzo(a)pyrene

Boron(*)

Bromate (iii)

Cadmium Chromium Clostridium Perfringens (including spores) Copper

Cyanide(*)

1,2 dichloroethane(*)

Enterococci

Fluoride(*)

Iron Lead Manganese

Mercury(*)

Nickel

Nitrate(ii)

Nitrite(ii)

Pesticides and related products(*)

Polycyclic aromatic hydrocarbons Selenium Sodium Trichloroethene/

Tetrachloroethene(*)

Tetrachloromethane(*)

Trihalomethanes

Chloride(*)

Sulphate(*)

Total organic carbon(*)

Tritium(*)

Gross alpha(*)(iv)

Gross beta(*)(iv)

<100 100–4,999

5,000–100,000

1 4 8

(*) Sampling for these parameters may be within water supply zones or at supply points as specified in Table 3,

subject to notes (ii) and (iii) below.

(i) Where the population is not an exact multiple of 5,000, the population figure should be rounded up to the

nearest multiple of 5,000.

(ii) Check monitoring in water supply zones is required only where chloramination is practised. In other

circumstances audit monitoring is required.

(iii) Audit monitoring in water supply zones is required only where sodium hypochlorite is added after water has left

the treatment works. In other circumstances, audit monitoring is required at supply points.

(iv) To monitor for total indicative dose (for radioactivity).


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TABLE 3 – ANNUAL SAMPLING FREQUENCIES: TREATMENT WORKS OR SUPPLY POINTS(*)

(1) Item

(2) Substances and parameters

(3) Volume of water supplied m3/d

(4) Reduced

(5) Standard

1. E. coli <20

20–1,999 2,000–5,999

6,000–11,999 ≥12,000

12 52

104 104

4 52

104 208 365

2. Coliform bacteria 3. Colony counts 4. Nitrite

(ii)

5. Residual disinfectant 6. Turbidity Subject to check monitoring 7. Clostridium perfringens

(i) <20

20–999 1,000–1,999 2,000–5,999 6,000–9,999

10,000–15,999 16,000–32,999 33,000–49,999 50,000–67,999 68,000–84,999

85,000–101,999 102,000–119,999 120,000–241,999

242,000–484,999 485,000–728,999

2 6

12 18 26 52 78

104 130 156 183 365 730

1,095

2 4

12 24 36 52

104 156

208 260 312 365 730

1,460 2,190

8. Conductivity

Subject to audit monitoring 9. Benzene

<20 20–999

1,000–49,999 50,000–89,999

90,000–299,999 300,000–649,999

≥650,000

1 4 8

12 24 36 48

10. Boron 11. Bromate

(iii)

11A. Clostridium Perfringens (including spores) 12. Cyanide 13. 1,2 dichloroethane 14. Fluoride 15. Mercury 16. Nitrite

(iia)

17. Pesticides and related products 18. Trichloroethene

Tetrachloroethene 19. Tetrachloromethane 20. Chloride 21. Sulphate 22. Total organic carbon 23. Tritium 24. Gross alpha

(iv)

25. Gross beta(iv)

(*) Sampling is at treatment works for the substances and parameters shown in column (1) of the Table as items 1 to

6 and at supply points for the other substances and parameters, except nitrite subject to notes (ii) and (iia) below.

(i) Check monitoring is required only in respect of surface waters (see regulation 6(2) and Table 1 in Schedule 3).

(ii) Sampling at treatment works when chloramination is practised. (iia) Sampling at treatment works when chloramination is not practised. (iii) Audit monitoring at supply points is required only where sodium hypochlorite is not added after water has left

the treatment works. In other circumstances, audit monitoring is required in water supply zones.

(iv) To monitor for total indicative dose (for radioactivity).


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ANALYTICAL METHODOLOGY

TABLE A1

PARAMETERS FOR WHICH, SUBJECT TO REGULATION 16(7), METHODS OF ANALYSIS ARE PRESCRIBED

(1) Parameter

(2) Method

Clostridium perfringens (including spores)

Membrane filtration followed by anaerobic incubation of the membrane on m-CP agar* at 44 & 1°C for 21 & 3 hours. Count opaque yellow colonies that turn pink or red after exposure to ammonium hydroxide vapours for 20 to 30 seconds.

Coliform bacteria ISO 9308-1 Colony count 22°C-enumeration of culturable microorganisms

PrEN ISO 6222

Colony count 37°C-enumeration of culturable microorganisms

prEN ISO 6222

Enterococci ISO 7899-2 Escherichia coli (E. coli) ISO 9308-1

*The composition of m-CP agar is: Basal medium Tryptose 30.0g Yeast extract 20.0g Sucrose 5.0g L-cysteine hydrochloride 1.0g MgSO4·7H2O 0.1g Bromocresol purple 40.0mg Agar 15.0g Water 1,000.0ml Dissolve the ingredients of the basal medium; adjust pH to 7.6 and autoclave at 121°C for 15 minutes. Allow the medium to cool and add: D-cycloserine Polymyxine-B sulphate Indoxyl- µ –D-glucoside to be dissolved in 8ml sterile water before addition Filter-sterilised 0.5% phenolphthalein diphosphate solution Filter-sterilised 4.5% FeCl3·6H2O

400.0mg 25.0mg 60.0mg 20.0ml 2.0ml

TABLE A2

PARAMETERS IN RELATION TO WHICH METHODS OF ANALYSIS MUST SATISFY PRESCRIBED CHARACTERISTICS

(1) Parameters

(2) Trueness % of

prescribed concentration or value

or specification

(3) Precision % of


or specification

(4) Limit of detection % of


or specification Aluminium 10 10 10 Ammonium 10 10 10 Antimony 25 25 25 Arsenic 10 10 10


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(1) Parameters

(2) Trueness % of


or specification

(3) Precision % of


or specification

(4) Limit of detection % of


or specification Benzene 25 25 25 Benzo(a)pyrene 25 25 25 Boron 10 10 10

Bromate 25 25 25 Cadmium 10 10 10 Chloride 10 10 10 Chromium 10 10 10 Colour 10 10 10 Conductivity 10 10 10 Copper 10 10 10

Cyanide(i)

10 10 10

1,2-dichloroethane 25 25 10 Fluoride 10 10 10 Iron 10 10 10 Lead 10 10 10 Manganese 10 10 10 Mercury 20 10 20 Nickel 10 10 10 Nitrate 10 10 10 Nitrite 10 10 10 Pesticides and

related products(ii)

25 25 25

Polycyclic aromatic

hydrocarbons(iii)

25 25 25

Selenium 10 10 10 Sodium 10 10 10 Sulphate 10 10 10

Tetrachloroethene(i

v)

25 25 10

Tetrachloromethane

20 20 20

Trichloroethene(iv)

25 25 10

Trihalomethanes:

Total(iii)

25 25 10

Turbidity(v)

10 10 10

Turbidity(vi)

25 25 25

(i) The method of analysis should determine total cyanide in all forms. (ii) The performance characteristics apply to each individual pesticide and will depend on the pesticide concerned.

(iii) The performance characteristics apply to the individual substances specified at 25% of the parametric value in Part I of Table B in Schedule 1.

(iv) The performance characteristics apply to the individual substances specified at 50% of the parametric value in Part I of Table B in Schedule 1.

(v) The performance characteristics apply to the prescribed value of 4 NTU. (vi) The performance characteristics apply to the specification of 1 NTU for water leaving treatment works.


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Appendix E – The Environmental Public Health (Quality of Piped Drinking Water) Regulations 2008

(Singapore Government & NEA, 2008)102

DRINKING WATER QUALITY STANDARDS Part I - Microbial parameters: 1. Escherichia coli (or alternatively, Thermotolerant coliform bacteria)

shall not be detectable in any 100 millilitre sample

Part II - Physico-chemical parameters: 1. Colour shall not exceed 15 True Colour Units 2. Turbidity shall not exceed 5 Nephelometric Turbidity Units 3. pH 6.5-9.5 Part III - Radiological parameters: 1. Gross Alpha activity shall not exceed 0.5 Becquerel/litre 2. Gross Beta activity shall not exceed 1 Becquerel/litre 3. Radon 222 concentration shall not exceed 100 Becquerel/litre Part IV - Chemical parameters: Maximum prescribed quantity

(milligrams/litre) Acrylamide 0.0005 Alachlor 0.02 Aldicarb Sulfoxide and Aldicarb Sulfone 0.01 combined Aldrin and Dieldrin 0.00003 Antimony 0.02 Arsenic 0.01 Atrazine 0.002 Barium 0.7 Benzene 0.01 Benzo[a]pyrene 0.0007 Boron 0.5 Bromate 0.01 Bromodichloromethane 0.06 Bromoform 0.1 Cadmium 0.003 Carbofuran 0.007 Carbon tetrachloride 0.004 Chlorate 0.7 Chlordane 0.0002 Chlorine1 5 Chlorite 0.7 Chloroform 0.3 Chlorotoluron 0.03 Chlorpyrifos 0.03 Chromium, in all forms as a total 0.05 Copper 2 Cyanazine 0.0006 Cyanide 0.07


Christopher Chua


Dissertation 2008

Maximum prescribed quantity (milligrams/litre)

Cyanide in Cyanogen Chloride form as part of total cyanogenic compounds

0.07

2,4-D(2,4-dichlorophenoxyacetic acid) in free acid form

0.03

2,4-DB [4-(2,4-Dichlorophenoxy) butyric acid] 0.09 DDT and metabolites 0.001 Di(2-ethylhexyl)phthalate 0.008 Dibromoacetonitrile 0.07 Dibromochloromethane 0.1 1,2-Dibromo-3-chloropropane 0.001 1,2-Dibromoethane 0.0004 Dichloroacetate 0.05 Dichloroacetonitrile 0.02 Dichlorobenzene, 1,2- 1 Dichlorobenzene, 1,4- 0.3 Dichloroethane, 1,2- 0.03 Dichloroethene, 1,2 0.05 Dichloromethane 0.02 1,2-Dichloropropane(1,2-DCP) 0.04 1,3-Dichloropropene 0.02 Dichlorprop 0.1 Dimethoate 0.006 Dioxane, 1,4- 0.05 Edetic acid (EDTA-Ethylene Diamine Tetraacetic Acid) in free acid form

0.6

Endrin 0.0006 Epichlorohydrin 0.0004 Ethylbenzene 0.3 Fenoprop (2,4,5-TP; 2,4,5-trichlorophenoxy propionic acid)

0.009

Fluoride 0.7 Hexachlorobutadiene(HCBD) 0.0006 Isoproturon 0.009 Lead 0.01 Lindane 0.002 Manganese 0.4 MCPA(4-Chloro-2-methylphenoxyacetic acid) 0.002 Mecoprop (MCPP; [2(2-methyl-chlorophenoxy) propionic acid])

0.01

Mercury, in inorganic form 0.006 Methoxychlor 0.02 Metolachlor 0.01 Microcystin-LR, in free and cell bound forms as a total

0.001

Molinate 0.006 Molybdenum 0.07 Monochloramine 3 Monochloroacetate 0.02 Nickel 0.07 Nitrate(as NO3-) 50


Christopher Chua


Dissertation 2008

Maximum prescribed quantity (milligrams/litre)

Nitrate plus nitrite combined The sum of the ratios of the concentrations of each to their maximum prescribed quantity

should not exceed 1 Nitrilotriacetic acid (NTA) 0.2 Nitrite (as NO2-) 3 Pendimethalin 0.02 Pentachlorophenol(PCP) 0.009 Permethrin, where used as a larvicide for public health purposes

0.3

Pyriproxyfen 0.3 Selenium 0.01 Simazine 0.002 Styrene 0.02 2,4,5-T(2,4,5-Trichlorophenoxyacetic acid) 0.009 Terbuthylazine(TBA) 0.007 Tetrachloroethene 0.04 Toluene 0.7 Trichloroacetate 0.2 Trichloroethene 0.02 Trichlorophenol, 2,4,6- 0.2 Trifluralin 0.02 Trihalomethanes The sum of the ratio of the

concentration of each Trihalomethane2 to its respective

maximum prescribed quantity should not exceed 1

Uranium (only chemical aspects of uranium addressed)

0.015

Vinyl chloride 0.0003 Xylenes 0.5 1 Where disinfection with chlorine is carried out, there should be a residual concentration of free chlorine of ≥0.5

mg/litre after at least 30 minutes contact time at pH<8.0 at the water treatment plant. 2 Refers to bromoform, bromodichloromethane, dibromochloromethane and chloroform.

Christopher Chua


Dissertation 2008

References

When indicated, the confidentiality agreement is observed. Copies of the confidential documents are kept by supervisor/course director.

1 United Nations General Assembly, United Nations Millennium

Declaration ARES/55/2, pp 1- 4, 18 Sep 2000.

2 Lenton R., Wright A.M. & Lewis K., UN Millennium project Task force on Water and Sanitation, Health, dignity & Development: what will it take?, pp xviii – xix, 2005

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4 World Health organisation, Health through safe drinking water and basic sanitation, [online], [cited 30 Jun 08], available at http://www.who.int/water_sanitation_health/mdg1/en/print.html

5 Prüss-Üstün A, Bos R, Gore F, Bartram J., Safer water, better health: costs, benefits and sustainability of interventions to protect and promote health, World Health Organization, pp 7, Geneva, 2008.

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7 World Health Organisation, Guidelines for Drinking-water Quality Third Edition First Addendum, Volume 1, pp (1-2, 8-9, 22 – 23, 72 – 75, 84 – 93, 486), 2006

8 Lloyd B.J, MSc Environmental Health module lecture notes – Sanitary indicator theory, University of Surrey, 2007

9 OECD & WHO, Assessing Microbial Safety of Drinking Water – Improving Approaches and methods, 2003

10 Thompson T., Fawell J., Kunikane S., Jackson D., Appleyard S., Callan P., Bartram J. & Kingston P., Chemical safety of drinking-water: assessing priorities for risk management, WHO, pp 3, 2007

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12 Allan S.C., The microbiological performance and operational characteristics of an integrated OXFAM Physico-chemical water treatment system MSc dissertation, UniS, pp 19, 1997

Christopher Chua


Dissertation 2008

13 Wikipedia, Water purification, [online] [cited 08 Aug 08], available at

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17 WHO, Constitution of the World Health Organisation, Basic Document, Forty-fifth edition, pp 1 – 18, Oct 2006

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22 Godfrey S. and Howard G., Water safety Plans (WSP) for urban piped water supplies in developing countries, WEDC, Loughborough University, UK, pp 4, 2004

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24 DWI, DWI – A brief guide to drinking water safety plans, pp 3, Oct 2005.

25 WHO, Water Safety Plans - Managing Drinking-Water Quality from Catchment to Consumer, 2005

Christopher Chua


Dissertation 2008

26 WHO, Guidelines for Drinking Water Quality – Second Edition,

Volume 3 – Surveillance and Control of community Supplies, pp 56, 1997

27 Hedeman-Robinson M., Enforcement of European Union Environment Law – Legal Issues & Challenges, pp 9, 2007.

28 European Community, European Community Environmental Legislation: Volume 7 – Water, pp iv-v, 1996

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30 Kallis G. & Nijkamp P., Evolution of EU Water Policy: A critical assessment and a hopeful perspective, pp (2, 14 - 16), 1999.

31 European Council, Council Directive 98/83/EC of 3 November 1998 on the quality of water intended for human consumption, pp 1 – 23, 3 Nov 98.

32 European Parliament, Consolidated version of the Treaty establishing the European Community, [online], [cited 17 Jul 08] , available at http://eur-lex.europa.eu/en/treaties/

33 CIA World Fact Book, United Kingdom, [online], [cited 19 Jul 08], , available at https://www.cia.gov/library/publications/the-world-factbook/geos/uk.html

34 Water UK, Water facts: The Water Industry Today, [online], [cited 19 Jul 08], available at http://www.water.org.uk/home/resources-and-links/waterfacts/waterindustry

35 May A., An assessment of the impact of regulatory models for drinking water quality in UK, University of Surrey, pp (9, 20, 37 – 39, 45, , 114 – 123, 266 – 268, 284 – 285), 2007

36 Water UK, The UK Water Industry (Sep 2007), [online], [cited 19 Jul 08] , available at http://www.water.org.uk/home/our-member

37 Water UK, Water facts – our regulators, [online], [cited 31 May 08] , available at http://www.water.org.uk/home/resources-and-links/waterfacts/water-regulators

38 UK parliament, The Water Supply (Water Quality) regulations 2000, pp (7-8, 16 -21, 26 - 28,), 2000

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Dissertation 2008

39 DWI, Guidance on the Water Supply (Water Quality Regulations

2000 (England) and the Water Supply (Water Quality) Regulations 2001 (Wales), pp 14, 2005

40 DWI, What is Regulations 31?, [online], [cited 02 Aug 08] , available at http://www.dwi.gov.uk/31/WhatisReg31.shtm

41 UK Parliament, Water Act 2003, pp 74, 2003

42 UK Parliament, Water Industry Act 1991, pp (58 & 63), 1991 [cited 29 May 08] , available at http://www.opsi.gov.uk/acts/acts1991/

43 Colbourne J., Personal communication with Prof. Jenni Colbourne, Chief Inspector of Drinking Water for England & Wales, 5 Aug 08

44 UK Parliament, The Private Water Supplies Regulations 1991, , 1991, [cited 29 May 08], available at http://www.dwi.gov.uk/regs/si2790/2790.htm

45 Ofwat, The development of the water industry in England & Wales, pp 54 -55, 2006, available at http://www.ofwat.gov.uk/aptrix/ofwat/publish.nsf/AttachmentsByTitle/development_of_water_industry270106.pdf/$FILE/development_of_water_industry270106.pdf

46 DWI, Information letter 03/2007 – New structure for the Drinking Inspectorate, [online], Annex A, 09 May 2007 [ cited 29 May 07], available at http://www.dwi.gov.uk/regs/infolett/2007/info0307.shtm

47 Rouse M., DWI Code of Enforcement, [online], DWI, [cited 20 Jul 08], available at http://www.dwi.gov.uk/consumer/faq/code4enforce.shtm

48 DWI, Information letter 6/2003- The Water Undertakers (Information) Direction 2003 - Format for provision of certain information, 2003, [cited 22 May 08] , available at http://www.dwi.gov.uk/regs/infolett/2003/info0603revised.shtm

49 Taylor A., Personal communication with Mr Andy Taylor, DWI water quality data manager, 28 Apr 08

50 DWI, DWI Information Letter 02/2004, pp 1-2, 16 Jan 04

51 DWI, DWI Guidance on notification, pp(4, 7-8, 12-13), 18 Feb 08

52 DWI, Events and incidents affecting drinking water quality, [online], [cited 21 Jul 08] , available at http://www.dwi.gov.uk/consumer/incidents/incidentindex.shtm

Christopher Chua


Dissertation 2008

53 DWI, Water company – Incidents and prosecutions, Events and

incidents affecting water quality, [online] [cited 20 Jul 08], available at http://www.dwi.gov.uk/consumer/incidents/incidentindex.shtm

54 DWI, What is Regulations 31?, [online], [cited 02 Aug 08], available at http://www.dwi.gov.uk/31/WhatisReg31.shtm

55 DWI, The approval scheme for products used in contact with water intended for human consumption, Advice sheet 1 – overview of application progress and general requirements, pp 4 – 7, 2008

56 Watts and Crane Associates, Evaluation of the Drinking Water Quality and Health Research Programme (1996-2004) for Defra, pp 5, 2006, available at http://www.dwi.gov.uk/research/reports/0848.pdf

57 Foster J., Personal communication with Dr Jim Foster, DWI Deputy Chief Inspector(Science & Strategy), 28 Apr 08

58 May A., Benefits of Drinking Water Quality Regulation – England & Wales, IWA Water Science & Technology, Vol 54, No. 11-12, pp 392, 2006

59 Wikipedia, Metaldehyde, [online], [cited 17 Jun 08], available at http://en.wikipedia.org/wiki/Metaldehyde

60 WHO & FAO, WHO/FAO datasheet on pesticideNo.93 – Metaldehyde, [online], Jul 96, [cited 10 Jun 08] , available at http://www.inchem.org/documents/pds/pds/pest93_e.htm#1.3

61 Clayden J., Greeves N., Warren S. & Wothers P., Organic Chemistry, Oxford University press, pp 1452, 2001

62 Bieri M., The Environmental profile of metaldehyde, Lonza Ltd, 2003

63 Nathan S.S., Murthy S.K. & Holden J.B., Organic Chemistry made simple, pp 44, 1975

64 WHO, The WHO recommended classification of pesticides by hazard and guidelines to classification : 2004, pp 23, 2005

65 PAN UK, PAN Pesticide Database: Physical properties, [online], 27 Jul 06, [cited 04 Aug 08] , available at http://www.pesticideinfo.org/Docs/ref_waterair1.html#Koc

66 USEPA, Registration Eligibility Decision (RED) document for Metaldehyde, pp 21, 2006

Christopher Chua


Dissertation 2008

67 National Pesticide Information Centre, NPIC OSU Extension Pesticide

Properties database – Metaldehyde, [online] [cited 5 Jul 08] , available at http://npic.orst.edu/ppdmove.htm

68 Rumsby P., Presentation on Emerging Contaminants, pp 17, National Centre for Environmental Toxicology, WRc plc, 2007

69 WRC plc, WRC new research projects 2008, [online] [cited 13 Aug 08] , available at http://www.wrcplc.co.uk/default.aspx?item=833

70 DWI, Drinking Water 2007 – Western Region (A report by the Chief inspector of Drinking Water, Drinking Water Inspectorate), pp 30, Jun 2008

71 DWI, Drinking Water 2007 – Incidents in 2007, pp 68, Jun 2008

72 DWI, Drinking Water 2007 – Thames Region (A report by the Chief inspector of Drinking Water, Drinking Water Inspectorate), pp 38, Jun 2008

73 Allen J., Personal communication with Ms Allen J., DWI Inspector, 19 Jun 08

74 Bristol Water plc, Water Quality in 2007, pp (4, 14), May 2008

75 PSD, Pesticide Law, [online] [cited 15 Aug 08] , available at http://www.pesticides.gov.uk/approvals.asp?id=869

76 PSD, PSD database on approved products, [online] [cited 08 Jul 08], available at https://secure.pesticides.gov.uk/pestreg/ProdList.asp

77 PSD, Revocation of authorized uses as a result of EC Maximum Residual Levels (MRLs) coming into force under EC Regulations 396/2005, [online], 24 Jul 08 [cited 4 Aug 08], available at http://www.pesticides.gov.uk/foor_safety.asp?id=2492

78 Water Company, Confidential report, confidentiality agreement observed, report copies kept by the course director, 2008

79 Water Company, Personal communication 1, confidentiality agreement observed, correspondence copies kept by the course director, 2008

80 Government agency, Personal communication 2, confidentiality agreement observed, correspondence copies kept by the course director, 2008

81 ASEAN Secretariat, Association of South East Nations – overviews, [online], [cited 17 Jul 08], available at http://www.aseansec.org/147.htm

Christopher Chua


Dissertation 2008

82 ASEAN secretariat, Third ASEAN State of the Environment Report

2006, pp 105-109,, 2006

83 ASEAN, Framework for Environmentally Sustainable Cities in ASEAN, [online], [cited 27 Jul 08], available at http://www.aseansec.org/framework.htm

84 ASEAN Secretariat, ASEAN Strategic plan of action on water resources management, pp 1-7, 2005.

85 WHO and UNCEF, WHO/UNICEF Joint monitoring programme – Water and sanitation database, [online] [cited 17 Jul 08]

86 UN ESCAP, UNDP & ADB, A future within reach 2008 – Regional partnership for the Millennium Development Goals in Asia & the Pacific, United Nations publication, pp 19 – 21, 2008

87 Biswas A., Interview with Prof Asit K. Biswas –“Global water problems are solvable”, The Impeller, 62:2003, pp 13, 2003

88 ADB, Country Water Action: Asia, Credible Regulatory Bodies — Managing Water Interests, [online] [cited 9 Jun 08], available at http://www.adb.org/water/actions/REG/regulatory-bodies.asp

89 McIntosh A.C., Asian Water Supplies- reaching the urban poor, Asian Development Bank and International Water Association, pp 105 – 116, 2003.

90 CIA, The World Factbook – Singapore, [online], [cited 4 Jul 08] , available at https://www.cia.gov/library/publications/the-world-factbook/geos/sn.html

91 Tortajada C., Water Management in Singapore, Water Resources Development Vol 22, No.2, pp (227, 229), Jun 06

92 Aziz I.S. and Cheney S., Singapore's quest to be less dependent on Malaysia for water started at separation, [online] , Channel Newsasia, [cited 25 Jun 08], available at http://www.channelnewsasia.com/stories/singaporelocalnews/view/356371/1/.html>

93 World Bank, Dealing with Water Scarcity in Singapore: Institution, Strategies and Enforcement, World Bank’s Analytical and Advisory Assistance Programme “China: Addressing Water Scarcity”, pp 2 – 4, Jul 2006

94 WHO & MEWR, Press release - World Health Organisation signs agreement with Singapore, pp 1, 15 Aug 2007

Christopher Chua


Dissertation 2008

95 Deere D. (WHO), Fong H.L (PUB), Woo C.H (PUB) and Wong Y.T. (PUB),

Training Mission report - Water Safety Plans Training of Trainers Workshop 3-5 Dec 07, pp 1 – 10, 2007, available at http://www.wpro.who.int/NR/rdonlyres/FABFA1B5-D50D-4FEF-9C28-0F320210484D/0/WSPWorkshopFinalTechnicalReport.pdf

96 MEWR, Ministry of Environment & Water Resources – Our History, [online] [cited 08 Aug 08], available at http://app.mewr.gov.sg

97 Ministry, Personal communication 3, confidentiality agreement observed, correspondence copies kept by the course director, 2008

98 PUB, Water Supply – History & Future of Water Supply, [online] [cited 21 Jun 08], available at http://www.pub.gov.sg/about/historyfuture/Pages/WaterSupply.aspx

99 WHOROE, International network of water regulators,[online] [cited 17 Jul 08], available at http://www.euro.who.int/watsan/CountryActivities/20060119_1

100 Singapore Government, The Public Utilities Act 2001 (Chapter 261), [online] [cited 11 Aug 08], available at http://statutes.agc.gov.sg/

101 Singapore Government, Environmental Public Health Act 1987 (Chapter 95), [online] [cited 10 Aug 08], available at http://statutes.agc.gov.sg/

102 Singapore Government & NEA, Environmental Public Health (Quality of piped drinking water)Regulations 2008, pp 3 – 12, 2008

103 NEA, Code of Practice on Piped Drinking Water sampling and Safety Plans, pp 6, Jan 2008

104 Lye L.H., A fine city in a garden – a study of environmental governance in Singapore, 4th International IUCN Academy Colloquium, pp 6, 2006

105 PUB, Water Loop, [online] [cited 20 Jun 08], available at http://www.pub.gov.sg/water/Pages/default.aspx

106 MEWR, Key Environmental Statistics – Water Resources Management, pp 7, 2008, available at http://app.mewr.gov.sg/web/Contents/Contents.aspx?ContId=682

107 Lee P.O (Institute of Southeast Asian Studies, Singapore), Water Management Issues in Singapore, Presented at Water in Mainland Southeast Asia, pp 6-8, 2005

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Dissertation 2008

108 PUB, NEWater – the 3rd National Tap, [online], [cited 13 Aug 08],

available at http://www.pub.gov.sg/water/Pages/NEWater.aspx

109 PUB, Press Release – “PUB awards tender for the fifth and largest NEWater plant at Changi to Sembcorp”, [online], 18 Jan 08, [cited 25 Jul 08], available at http://www.pub.gov.sg/mpublications/Pages/PressReleases.aspx?ItemId=178

110 Hyflux, Brochure - Singspring Desalination Plant at Tuas, pp 1 – 2, [online], 17 Nov 05 [cited 11 Aug 08], available at http://www.hyflux.com

111 Haja N., Personal communication with Mr Nazarudeen, Assistant Director, Water Supply (Network) Department, PUB, 17 Jul 08

112 Kok T.W, Lim K.S., Loh M.W., Haja N., Wong K.W, Soh T., Tiew K.N. and Lee M.F., Integrated Water Quality Management – Singapore’s Experience, SIWW, pp 1 – 9, 2008

113 Woo C.H., Personal communication with Mr Woo C.H., Executive Microbiologist, Technology & Water Quality Office, PUB, 24 Jul 08

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