Generic Framework and Methods for Integrated Risk Management in Water Safety Plans

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Generic Framework
and Methods for
Integrated Risk
Management in Water
Safety Plans


Techneau, 07.
JUNE 2007


© 2006 TECHNEAU
TECHNEAU is an Integrated Project Funded by the European Commission under the Sixth Framework
Programme, Sustainable Development, Global Change and Ecosystems Thematic Priority Area
(contractnumber 018320). All rights reserved. No part of this book may be reproduced, stored in a database
or retrieval system, or published, in any form or in any way, electronically, mechanically, by print,
photoprint, microfilm or any other means without prior written permission from the publisher

TECHNEAU
Generic Framework and Methods for
Integrated Risk Management in Water
Safety Plans



Techneau, 07.
JUNE 2007



















This report is:
PU = Public
Colofon
Title
Generic Framework and Methods for Integrated
Risk Management in Water Safety Plans

Authors
L. Rosén
1
, P. Hokstad
2
, A. Lindhe
1
, S. Sklet
2
,
J
. Røstum
2

1
Chalmers University of Technology
2
SINTEF

Quality Assurance
By KIWA and LNEC

Deliverable number
D 4.1.3
D 4.2.1
D 4.2.2
D 4.2.3




Chalmers & SINTEF Rosén, Hokstad, Lindhe, Sklet & Røstum
© TECHNEAU - 1 - June 14, 2007

Summary
In the 3
rd
edition of the Guidelines for Drinking-water Quality, the World
Health Organisation (WHO, 2004) emphasis the preparation of risk-based
Water Safety Plans (WSPs) to manage risks to drinking water consumers.
WHO, among others, emphasise that the entire supply system, from source to
tap, should be considered when managing risks. The WSP framework
facilitates a much needed increase in awareness and understanding of risk
issues for providing safe drinking water. However, an analysis of the WSP
framework indicates that there are opportunities for further development,
primarily regarding risks to water quantity and methods for risk
identification, risk estimation and risk evaluation.

The main objective of Work Area 4 (WA4) – Risk Assessment and Risk
Management in TECHNEAU (TECHNEAU, 2005) is: to integrate risk
assessments of the separate parts in drinking water supplies into a comprehensive
decision support framework for cost-efficient risk management in safe and sustainable
drinking water supply. The framework should be regarded as a structure and
toolbox for risk assessment and risk management in WSP. It should be
applicable to both groundwater and surface water supply systems, with basic
as well as more complex designs. The framework should also be applicable
on both the operational and strategic levels.

A generic framework which forms the basis for further development of risk
management procedures and methods in TECHNEAU is presented in this
report. The main components of the suggested framework are shown in
Figure 1. To provide the necessary basis for integrated risk management for
both basic and complex systems on the operational as well as strategic levels,
the framework includes all major steps in the risk management process, as
defined in established standards, e.g. IEC (1995).

To be efficient and functional, the framework must also include a set of
reliable and well-established tools, adapted to specific decisions to be made
and considering type of water supply system, level of complexity, and level of
decisions, i.e. operational or strategic. Principal levels of sophistication of risk
assessment tools are:
- Qualitative, e.g. based on checklists and classification of risk levels,
providing relative ranking of lists and identification of critical points
for risk reduction.
- Quantitative, e.g. based on models for combining and structuring
events and chains of events, and estimations of quantitative risk
levels. This level of sophistication facilitates quantitative comparison
of estimated risk levels with established risk tolerability levels.
- Quantitative including decision analysis methods, facilitating strategic
analysis of risk reduction measures, e.g. estimations of the risk
reduction – investment trade-offs in prioritisation of risk reduction
options.

Chalmers & SINTEF Rosén, Hokstad, Lindhe, Sklet & Røstum
© TECHNEAU - 2 - June 14, 2007
Risk Analysis
Define Scope
Identify and Estimate
Risks
Qualitative
Quantitative
Risk Evaluation
Define tolerability criteria
Water quality
Water quantity
Analyse risk reduction
options
Ranking
Cost-efficiency
Cost-benefit
Risk Reduction/
Control
Report risks
Make decisions
Treat risks
Report residual risks
Monitor
Get new
information
Update
Develop
supporting
programmes
training,
hygiene
practices,
upgrade and
improvement,
research and
development
Document –
assure
quality
Communi-
cate
Review,
approve and
audit

Figure 1. The main components of the TECHNEAU generic framework for integrated risk
management in WSP.

The suggested framework cannot provide one single risk management
method applicable to all types of water utilities for decisions at both strategic
and operational levels. Instead, the framework when fully developed will
provide:
- Principles for good risk management practice
- The relevant set of tools necessary for performing the risk assessment
and management
- Description of these tools, e.g.:
o
TECHNEAU Hazard database, THDB
o
Risk analysis methods description
o
TECHNEAU Risk reduction options database, TRDB
o
Decision support tool
- Clear examples of risk assessment applications and testing of these
tools.

Chalmers & SINTEF Rosén, Hokstad, Lindhe, Sklet & Røstum
© TECHNEAU - 3 - June 14, 2007
Contents
Summary 1

Contents 3

1

Introduction 5

2

The risk management process 9

2.1

Introduction 9

2.2

Risk analysis 10

2.3

Risk evaluation 11

2.4

Risk reduction/control 14

2.5

Risk communication 15

2.6

Notation 15

2.7

Generic guides for risk management 16

3

Existing frameworks and national guidelines 19

3.1

Review of existing frameworks for drinking water management 19

3.1.1

The Bonn Charter 19

3.1.2

Hazard Analysis and Critical Control Point 19

3.1.3

Water Safety Plans 22

3.1.4

The Water Framework Directive 25

3.1.5

Integrated Water Resources Management 25

3.1.5.1

Agenda 21 26

3.2

Examples on national guidelines 26

3.2.1

EU - The Directive on the Quality of Water (“Drinking water directive”) 26

3.2.2

Switzerland 26

3.2.3

Germany 27

3.2.4

UK – Yorkshire water 29

3.2.5

Denmark 29

3.2.6

Sweden 30

3.2.7

Norway 30

3.2.8

The Netherlands 30

3.2.9

USA 31

3.2.10

The Canadian Multi-Barrier Approach 31

3.2.11

Australian framework 32

3.2.12

New Zealand Public Health Risk Management Plan 35

3.3

Comparison and discussion 37

4

The TECHNEAU generic framework for integrated risk management 45

5

Review of risk analysis methods 51

5.1

Introduction 51


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© TECHNEAU - 4 - June 14, 2007
5.2

Scope definition and system description 51

5.3

Hazard identification 52

5.3.1

HAZID analyses 52

5.3.2

Hazard and operability analysis (HAZOP) 55

5.4

Risk estimation 57

5.4.1

Preliminary hazard analysis (PHA) 57

5.4.2

Failure Modes, Effects, and Criticality Analysis (FMECA) 58

5.4.3

Fault tree analysis 59

5.4.4

Reliability block diagram 60

5.4.5

Event tree analysis 60

5.4.6

Human reliability assessment (HRA) 61

5.4.7

Physical modelling of processes in source, treatment, and distribution 62

5.4.8

Health risk assessment 62

5.4.9

Health impact assessment 64

5.4.10

QMRA (Quantitative Microbiological Risk Assessment) 64

5.4.11

Barriers and Bow-Tie diagrams 66

5.4.12

Tools in risk quantification 68

5.4.12.1

Markov models 68

5.4.12.2

Risk influence diagrams / Bayesian belief networks 68

5.4.12.3

Monte Carlo simulation 68

5.4.13

Risk measures in water supply systems 69

5.4.13.1

Water quality 69

5.4.13.2

Water quantity 70

5.4.13.3

Individual and societal risks 70

5.4.13.4

Economic valuation of risks 71

5.5

Summary of risk analysis methods 73

6

Case examples 77

6.1

Introduction 77

6.2

Göteborg case 77

6.3

Bergen case 78

6.4

Combined use of risk analysis methods 82

7

Risk evaluation approaches 87

7.1

Decision situations 87

7.2

Risk evaluation 88

8

Conclusions and further work 91

9

References 95

Appendix A 101




Chalmers & SINTEF Rosén, Hokstad, Lindhe, Sklet & Røstum
© TECHNEAU - 5 - June 14, 2007
1 Introduction
In the 3
rd
edition of the Guidelines for Drinking-water Quality, the World
Health Organisation (WHO, 2004) concludes that analyses of water quality in
treatment and distribution systems are not sufficient to guarantee safe
drinking water to consumers. Such analyses are often completed after the
water was consumed and they may not provide correct information
regarding the health effects of the water. Instead, WHO (2004) recommends
preparation of risk-based Water Safety Plans (WSPs) that consider conditions
in source waters, treatment systems and distribution networks. WSP is
currently being implemented in several countries and is expected to become
an increasingly important framework for water management in both
developed and developing countries.

The WSP guidelines describe risk assessment on a principal level, based on
the Hazard Analysis and Critical Control Point (HACCP) approach. HACCP
was originally developed for the food industry (Havelaar, 1994). Because of
its origin in HACCP, current WSP practice puts more focus on risk
assessments concerning quality and human health than on water quantity,
including water security and water supply.

The WSP framework facilitates a much needed increase in awareness and
understanding of risk issues for providing safe drinking water. The WSP
framework, however, offers opportunities for further development regarding
considerations of water quantity issues, as well as other stakeholder values.
There are also opportunities to further develop WSP regarding more specific
methods for risk identification, estimation and evaluation in order to provide
cost-effective and sustainable prioritisation of safety measures. The main
objective of Work Area 4 (WA4) – Risk Assessment and Risk Management in
TECHNEAU (TECHNEAU, 2005) is: to integrate risk assessments of the separate
parts in drinking water supplies into a comprehensive decision support framework for
cost-efficient risk management in safe and sustainable drinking water supply, see
Figure 2.


Source water
systems
Treatment
systems
Distribution
and plumbing
networks
Integrated Risk Assessment
and Risk Management

Figure 2. Integrated risk assessment and risk management of a water supply system.

Chalmers & SINTEF Rosén, Hokstad, Lindhe, Sklet & Røstum
© TECHNEAU - 6 - June 14, 2007
The framework should be regarded as a structure and toolbox for risk
assessment and risk management in WSP. It should be applicable to both
groundwater and surface water supply systems, with basic as well as more
complex designs. The framework should be developed in full concordance
with the Bonn Charter strategy (IWA, 2004), which supports and further
specifies the use of WSP in water safety assessment. The risk management
framework should also be applicable on both the operational and strategic
levels, see Figure 3. Here the strategic decisions could relate e.g. to
modifications or formulation of maintenance strategy.

Surface water
Ground water
Basic s
y
stems Com
p
lex s
y
stems
Operational
Strategic

Figure 3. Schematic description of the applicability of the integrated framework for risk
management in Water Safety Plans (WSPs).

In the initial step of the development, stakeholder values will be limited to
water safety, or even only to compliance with regulated limit values. Further
values, e.g. ecological and socio-cultural values, will be added in a second
step in order to more fully consider sustainability issues.

To provide the necessary basis for integrated risk management for both basic
and complex systems on the operational as well as strategic levels, the
framework must include all major steps in the risk management process, as
defined in established standards, e.g. IEC (1995), see Chapter 2. The current
WSP guidelines are primarily directed at risk identification and qualitative
risk assessment for ranking of risks, whereas quantitative risk estimation, risk
evaluation, decision-making and risk communication are not described
extensively.

To be efficient and functional, the framework must also include a set of
reliable and well-established tools, adapted to specific decisions to be made
and considering type of water supply system, level of complexity, and level of
decisions, i.e. operational or strategic. The current WSP guidelines provide
general descriptions of risk identification approaches and qualitative (or
semi-quantitative) approaches to risk estimations, but do not give detailed

Chalmers & SINTEF Rosén, Hokstad, Lindhe, Sklet & Røstum
© TECHNEAU - 7 - June 14, 2007
guidance on specific methods nor quality criteria for risk management.
Principal levels of sophistication of risk assessment tools are:
- Qualitative, e.g. based on checklists and classification of risk levels,
providing relative ranking of lists and identification of critical points
for risk reduction.
- Quantitative, e.g. based on models for combining and structuring
events and chains of events, and estimations of quantitative risk
levels. This level of sophistication facilitates quantitative comparison
of estimated risk levels with established risk tolerability levels.
- Quantitative including decision analysis methods, facilitating strategic
analysis of risk reduction measures, e.g. estimations of the risk
reduction – investment trade-offs in prioritisation of risk reduction
options.

This document provides reviews and descriptions of WSP, other frameworks
and specific methods for risk assessment and risk management in water
supply. The overall aim of this report is to identify possibilities for further
development regarding the structure and specific tools for more
comprehensive risk management in WSP. Specific objectives of this document
are:
1. To describe a generic framework for integrated risk management in
Water Safety Plans (WSPs).
2. To describe specific risk analysis methods suitable for use in
integrated risk management of water supplies.

To meet these objectives this report includes the following main sections:
- A description of the general risk management process.
- A review of existing frameworks and national guidelines for risk
management in water supply.
- An outline of a proposed generic framework for integrated risk
management in WSP.
- A review of specific risk analysis methods.
- Suggestions of possible risk analysis methods for integrated risk
management.

Note that in this report the term water safety comprises both water quality and
water quantity. The notation is further discussed in Section 2.6.

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© TECHNEAU - 8 - June 14, 2007

Chalmers & SINTEF Rosén, Hokstad, Lindhe, Sklet & Røstum
© TECHNEAU - 9 - June 14, 2007
2 The risk management process
2.1 Introduction
Although some differences can be found in the literature regarding
presentation and outline of the risk management process, there is a rather
strong consensus regarding the major contents of the process. The outline
shown in Figure 4 is commonly used and is often referred to. According to
IEC (1995) the objective of the overall process called risk management is to
control, prevent or reduce loss of life, illness, injury, damage to property and
consequential loss, and environmental impact. It should be emphasized that
an efficient risk management not only protects us from hazards, it also creates
opportunities. If a risk is unknown this might restrain us from performing a
specific project. However, if the risk is analysed and understood, and it is
possible to reduce or control the risk, then the project can be performed.

The risk management process includes the entire process from the initial
description of the scope and purpose of risk management, the identification
of hazards, and the estimation of risks, through the evaluation of risk
tolerability and identification of potential risk reduction options, to the
selection and implementation of appropriate risk reduction measures.

Risk management also includes risk monitoring and follow up during
operation. So it should be emphasized that risk management is an iterative
process of continuous updating as new information becomes available and as
the preconditions change. Successful risk management also requires careful
communication of risks between the various involved stakeholders.


Figure 4. The risk management process (IEC, 1995).

Risk analysis

Scope definition

Hazard identification

Risk estimation
Risk evaluation

Risk tolerability decisions

Analysis of options
Risk reduction/control

Decision making

Implementation

Monitoring
Risk
assessment
Risk
management

Chalmers & SINTEF Rosén, Hokstad, Lindhe, Sklet & Røstum
© TECHNEAU - 10 - June 14, 2007
As stated in Vatn (2004), there is no universally agreed definition of risk. A
definition of risk presented by Kaplan (1997) is valuable both when
communicating and assessing the risk situation. Kaplan states that the
question “What is the risk?” is really three questions; “What can happen?”,
“How likely is that to happen?”, and “What are the consequences?”. Risk may
then be expressed as a (complete) set of triplets (S
i
, L
i
, X
i
), where S
i
denotes
scenario i, L
i
denotes the likelihood, and X
i
the consequences.

Similarly, according to IEC (1995), risk analysis attempts to answer three
fundamental questions:
- What can go wrong? (identification of hazardous events)
- How likely is this to happen?
- What are the consequences?

This view is in line with Kaplan’s definition of risk. A common description of
risk is that it is a combination of the probability and the consequence of a
hazardous event, see e.g. ISO (2002), European Commission (2000a) and IEC
(1995).

2.2 Risk analysis
Risk analysis is a major part of risk management. As seen in Figure 4 the first
tasks of a risk analysis are scope definition and identification of
hazards/hazardous events. The next step is the estimation of the level of risk
resulting from possible hazardous events. This includes both causal
analyses/tools to identify the causes and frequencies of these undesired
events, and analyses/techniques to investigate their consequences. In Figure
5 a more detailed description of the risk analysis process is presented.

The purpose of risk analysis is to obtain information and knowledge about
the risk. This information and knowledge are later used when evaluating the
risk and in the end, if it is considered necessary, performing risk reduction
measures. The risk analysis varies depending on the system that is being
analysed and what kind of risk is considered. A risk analysis can be either
qualitative or quantitative, depending on its purpose and the risk. The
analysis may also be semi-quantitative, which is something between a
quantitative and qualitative analysis. When performing a risk analysis it is
important to choose which endpoints or consequences to include and also to
decide which measures to use. Slovic (2001) emphasize that the choice of one
measure or another can make a technology look either more or less risky.


Chalmers & SINTEF Rosén, Hokstad, Lindhe, Sklet & Røstum
© TECHNEAU - 11 - June 14, 2007

Figure 5. The risk analysis process (after IEC, 1995).

2.3 Risk evaluation
The purpose of the risk evaluations is to decide whether or not a risk is
tolerable. If the risk is decided to be acceptable it may be enough to control
the risk instead of reducing it. However, if the risk is decided to be
unacceptable different risk reduction options has to be analysed and
compared so that the best risk reduction option can be identified.

Scope definition
• Describe concerns
• Define system
• Define circumstances
• State assumptions
• Identify analysis decisions
Documentation
• Risk analysis plan
Hazard identification and initial
consequence evaluation
• Identify hazards
• Analyse consequences
Start
Sto
p
Analysis update
when appropriate
Risk estimation
• Analyse frequencies
and/or probabilities
• Analyse consequences

Calculate risk
Risk
estimation
required?
Documentation
• Risk analysis report
Analysis verification

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© TECHNEAU - 12 - June 14, 2007
Different categories of stakeholders are in different ways and to different
extents involved in the risk management process. It is important to realize
that stakeholders exposed to the specific risks may not always be those
benefiting from the risk generating activities. For example, industries in a
catchment area of a water supply will benefit from their production, but they
will also contribute to water safety risks to consumers which have no benefit
from the industrial activities. Grimvall (1998) described the principal types of
stakeholders affected by decision-making involving risks, see Figure 6.

Those exposed
to risks
Those
benefiting from
risk generating
activities
Decision-makers

Figure 6. Main categories of stakeholders affected by decisions on risk (Grimvall, 1998).

Due to the multi-dimensional character of decision-making regarding risk
issues, it is of primary importance that the evaluation of risks and the
decision-making are made with respect to criteria and principles that are
agreed upon among the affected stakeholders. There are different principles
described in the literature for evaluation of risks and it is important that the
used principle is openly communicated and accepted by the involved
stakeholders. The evaluation principles form the basis for defining risk
tolerability. An example of a principle currently much referred to is the
ALARP (As Low As Reasonably Practicable), see Figure 7. According to this
principle, risks that are clearly unacceptable must be reduced or eliminated
under any circumstances. Risks that are clearly acceptable can be left without
further actions. In between the acceptable and unacceptable risks there are
risks that may be accepted if it is economically and/or technically
unreasonable to reduce them. A principle closely related to ALARP, and with
the same meaning, is ALARA (As Low As Reasonably Achievable)
(Davidsson et al., 2002).


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Acceptable
Risk
ALARP Region
The risk can be
accepted if it is
economically and
technically
unreasonable to
reduce it
Unacceptable Risk
The risk cannot be accepted
under any circumstances

Figure 7. The ALARP (As Low As Reasonably Practicable) Principle (Melchers, 2001).

Risk tolerability criteria, based e.g. on the ALARP principle, can be showed in
risk matrices, where estimated probability and consequences are graphically
displayed in relation to the defined risk tolerability levels, see Figure 8.

Probability
Consequences

Figure 8. Risk matrix with ALARP zones.

Also other principles exist and Davidsson et al. (2002) present the following
four general approaches that can be used when evaluating risk:
- Principle of reasonableness – If it is reasonable with respect to
economical and technical means, the risk shall be reduced regardless
the level of risk.
- Principle of proportionality – The overall risk resulting from an
activity should not be unreasonably large compared to the benefits.
- Principle of allocation – The allocation of risk in society should be
reasonable/fair compared to how the benefits are allocated.

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© TECHNEAU - 14 - June 14, 2007
- Principle of avoidance of disasters – Risks with disastrous
consequences should be avoided so that the consequences can be
managed with accessible resources.

The principle of reasonableness is closely related to the ALARP principle.
Risk evaluation is further discussed in Section 7.2.

The risk tolerability levels must be defined taking peoples perception and
aversion of risks into consideration. The public perception has for example
been found to have an important affect on the priorities and legislative
agendas of regulatory bodies (Slovic, 2001). Examples on factors affecting
peoples risk aversion are:
- Catastrophic potential
- Familiarity
- Uncertainty
- Individual or societal
- Controllability
- Voluntariness

Renn (1998) mention that technical analyses of risk have drawn much
criticism from the social science. One reason to this is that the technical
analyses not are considered to include people’s perception of risk and social
constructions. Klinke and Renn (2002) present nine criteria to be used for
evaluating risk. These criteria are meant to include more than just the extent
of damage and probability of occurrence when evaluating risks. The nine
criteria are:
- Extent of damage
- Probability of occurrence
- Incertitude
- Ubiquity
- Persistency
- Reversibility
- Delay effect
- Violation of equity
- Potential of mobilization

2.4 Risk reduction/control
If the risk evaluation has the result that risk is not acceptable, it is required to
carry out risk reduction, also called risk treatment. If the risk is decided to be
acceptable it may be enough to control the risk instead of reducing it. When
risk reducing measures are carried out the action plans for risk
prevention/mitigation should, according to the Australian-New Zeeland risk
management standard (AS/NZS 4360:2004), include:
1. the planned actions;

Chalmers & SINTEF Rosén, Hokstad, Lindhe, Sklet & Røstum
© TECHNEAU - 15 - June 14, 2007
2. the existing/required resources;
3. the involved responsibilities;
4. their duration; and
5. action tracking and controlling measures.

Suggestions for risk reducing measures should be an outcome of the risk
assessment. When reducing the risk different approaches can be used. Based
on the description of risk as a combination of the probability and the
consequence of a hazardous event, three different approaches can be
identified. Two of the approaches are based on reducing one of the
parameters, i.e. the consequence or probability. The third approach is based
on reducing both parameters at the same time.

One risk reduction measure is denoted risk avoidance; i.e. an activity or
process being a source of risk is not started or is discontinued. Sometimes we
are looking for risk optimization; i.e. implementation of actions to minimize
negative consequences/maximize the positive ones, possibly reducing the
probability of the occurrence of undesirable events.

2.5 Risk communication
According to the Swedish Rescue Services Agency (SRA, 2003) the purpose of
risk communication is to increase the public’s knowledge about risk related
questions and make them participate in the risk management. Owen et al.
(1999) point out that communication of risks related to drinking water
between laypeople and experts are complicated due to the difference in
knowledge. To be efficient the risk communication has to be a two-way
process enabling both parts to contribute. When managing risks to drinking
water systems it is important to communicate with all three stakeholders
presented in Figure 6.

One important part of risk communication is how to present the risk. Slovic
(2001) point out that different ways of presenting the same risk information
can lead to different evaluations and decisions, even though they are logically
equivalent. The fact that peoples perception of risk differs is one of the
reasons why risk communication is complicated.

2.6 Notation
Integration of risk management requires careful coordination with respect to
harmonisation of terminology, commonality in approach, and measurement
of risk in comparable units. Terms commonly used in risk management are
defined differently by different actors. The following notation and definitions
of terms are based on IEC (1995) and are applied in the TECHNEAU project:
- Risk is a combination of the frequency, or probability, of occurrence
and the consequence of a specified hazardous event.
- Hazard is a source of potential harm or a situation with a potential of
harm.

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© TECHNEAU - 16 - June 14, 2007
- Hazardous agent is for example a biological, chemical, physical or
radiological agent that has the potential to cause harm.
- Hazardous event is an event which can cause harm.
- Hazard identification is the process of recognizing that a hazard exists
and defining its characteristics.
- Risk estimation is the process used to produce a measure of the level of
risk being analysed. Risk estimation consists of the following steps;
frequency analysis, consequence analysis, and their integration.
- Risk analysis is the systematic use of available information to identify
hazards and to estimate the risk to individuals or populations,
property or the environment.
- Risk evaluation is the process in which judgements are made on the
tolerability of the risk on the basis of risk analysis and taking into
account factors such as socio-economic and environmental aspects.
- Risk assessment is the overall process of risk analysis and risk
evaluation.
- Risk management is the systematic application of management policies,
procedures and practices to the tasks of analysing, evaluating,
controlling risk.

Note that WHO defines hazard and risk in the following way (WHO, 2004):
- A hazard is a biological, chemical, physical or radiological agent that
has the potential to cause harm.
- Risk is the likelihood of identified hazards causing harm in exposed
populations in a specified frame, including the magnitude of that
harm and/or the consequences.

The definition of hazard given by WHO is not used in TECHNEAU because it
only considers health related hazards. The WHO definition of hazard is
similar to how a hazardous agent is defined above. A hazard does not have to
be an agent in the water, since other sources of harm exist. The definition of
risk given above is similar to the WHO definition; both definitions include
probability/likelihood and consequence. However, the WHO definition
indicates that only health related risks are considered.

2.7 Generic guides for risk management
There are various standards and guidelines for risk management. Some
examples are:
- AS/NZS standard 4360:2004. Risk management. ISBN 0733759041 -
Standards Australia / Standards New Zealand.
- CEI/IEC (1995). 300-3-9 Dependability management - Part 3:
Application guide - Section 9: Risk analysis of technological systems.
- ISO/IEC (1999). Guide 51 Safety aspects - Guidelines for their
inclusion in standards.

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- ISO/IEC (2002). Guide 73 Risk management - Vocabulary - Guidelines
for use in standards.

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Chalmers & SINTEF Rosén, Hokstad, Lindhe, Sklet & Røstum
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3 Existing frameworks and national
guidelines
3.1 Review of existing frameworks for drinking water management
There exist various strategies and frameworks relevant for water
management and some of these are described and discussed below. The
frameworks and the more general risk management process have been
compared and similarities as well as differences have been identified and are
presented.

3.1.1 The Bonn Charter
The Bonn Charter for Safe Drinking Water (IWA, 2004) is a high level
framework consisting of key principles that are basic requirements for
managing water supplies from catchment to consumer. It also provides
guidance to the institutional roles and responsibilities. The principles
presented in the Bonn Charter are supposed to be applicable from source to
tap and the goal is good safe drinking water that has the trust of consumers.
According to the document, safe drinking water is fundamental to a healthy
community and to its economic development. Drinking water should,
according to the Bonn Charter, not just be safe to drink but also have an
aesthetic good quality. It is emphasized that risks should be assessed at all
points throughout the system and this requires a close co-operation between
all stakeholders. The Bonn Charter is a complementary document to the
Guidelines for Drinking-water Quality of the World Health Organisation
(WHO, 2004) and the use of Water Safety Plans (WSPs) is emphasized. To
shortly summarize the Bonn Charter it can be described as a document that
clearly states the importance of drinking water to humans and advocates that
the entire drinking water system is considered when managing risks.

3.1.2 Hazard Analysis and Critical Control Point
The Hazard Analysis and Critical Control Point (HACCP) system was
originally conceived by the Pillsbury Company in 1960 to assure food safety
when delivering food to the NASA space program, and it has later been used
by the food industry to assure safe food production (Dewettinck et al., 2001).
The HACCP principles are described by the Codex Alimentarius Commission
(Codex, 2003) and Havelaar (1994) describes the application of HACCP to
drinking water supply with main emphasis on microbial contamination.
According to Havelaar (1994) HACCP had not formally been applied to the
drinking water supply before 1994.

According to the Codex Alimentarius Commission (2003) HACCP is a
science-based and systematic system that identifies specific hazards and
measures for their control to ensure safety. Dewettinck et al. (2001) describes
HACCP as a preventive system that helps to assure that all products reaching

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the consumer are safe for consumption. The system is supposed to be
compatible with the ISO 9000 series and other quality management systems
(Codex, 2003).

The key steps when applying the HACCP approach are presented in Figure 9.
The first step is to assemble a team, when doing this it is important to make
sure that all necessary knowledge and expertise are available within the team.
In this step the scope of the application of HACCP should also be identified.
Describing the product and identifying intended use are not as important
when applying the HACCP approach to drinking water systems as if it is
applied in the food industry. Nevertheless some attention should be paid to
the drinking water consumption of the local population (Havelaar, 1994). The
next steps are constructing a flow diagram and confirm it against the real
system. All the five first steps can be described as preparatory to the
following work with hazards.

For each step in the drinking water system the HACCP team should list all
hazards that may be reasonably expected to occur. The hazard analysis aims
at identify which hazards that yields such a risk that they need to be
eliminated or reduced to acceptable levels. The Codex Alimentarius
Commission (2003) defines a hazard as a biological, chemical or physical agent in,
or condition of, food with the potential to cause an adverse health effect. For each
hazard control measures must be identified and critical control points (CCPs)
determined. In the food industry a CCP is defined as a step at which control
can be applied and is essential to prevent or eliminate a food safety hazard or
reduce it to an acceptable level. More than one control measure may be
required to control a specific hazard and more than one hazard may be
controlled by a specified control measure. If no control measure can be
identified for a hazard, the system has to be modified in a way that makes a
control measure arise.

For each CCP critical limits must be established, which are supposed to
indicate when something is wrong. A monitoring system including scheduled
measurements or observations should be established for each CCP and is
supposed to detect loss of control in time to make adjustments. Corrective
actions must be specified and documented to make sure the CCP can be
brought under control. To make sure the entire HACCP system is working
correctly, verification procedures need to be established. Also the
documentation and record keeping is important to a successful application of
HACCP.


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Figure 9. Steps in the HACCP approach (Codex, 2003).

An extract from a generalized HACCP analysis of drinking water production
is shown in Table 1.

Table 1. Extract from a generalized HACCP analysis of drinking water production (Havelaar,
1994).
Process step Hazards
Preventive
measures
CCP?

CCP
parameters
Monitoring
procedures
Corrective
actions
Groundwater
abstraction




Storage of
surface water
in reserviors

Transport of
pathogens to
well-head



Short circuiting
Define
protection
zone and
restrict
land-use

Build
reservoirs
in series
Yes





No
Travelling
time




-
Tracer
injection
studies
Specific
pathogens

Tracer
studies
Conservative
parameters
Fecal index
bacteria
Remove
sources of
pollution



Increase
treatment

Even though the HACCP system most commonly is applied by the food
industry it may also be applied for water safety. One important question to
Assemble HACCP team
Describe product
Identify intended use
Construct flow diagram
On-site confirmation of flow diagram
List all potential hazards, conduct a hazard
analysis and consider control measures
Determine CCPs
Establish a monitoring system for each CCP
Establish corrective actions
Establish verification procedures
Establish documentation and record keeping
Establish critical limits for each CCP

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ask is what range of application the HACCP system has in the drinking water
system? According to the Australian Drinking Water Guidelines
(NHMRC/NRMMC, 2004) HACCP is aligned quite readily on the treatment
component of drinking water supply and may not as easily be applied to the
important areas of catchment and distribution system. Havelaar (1994) points
out that several steps in the system are important to assure the quality of the
final water, but cannot be considered as CCPs under the responsibility of the
water producer because of a lack of a direct control.

3.1.3 Water Safety Plans
In 2004 the WHO presented the 3
rd
edition of the Guidelines for Drinking-
water Quality (WHO, 2004). The guidelines aim to protect public health and
are intended to support the development of risk management strategies. Safe
drinking water is defined as such that does not represent any significant risk to
health over a lifetime of consumption, including different sensitivities that may occur
between life stages. The access to safe dinking water is emphasized as essential
to health and a basic human right.

To ensure safe drinking water a holistic risk assessment and risk management
approach is emphasized as well as the importance of considering the entire
drinking water system, from catchment to consumer. The WHO presents a so
called framework for safe drinking water, consisting of the following five key
components:
1. Health-based targets based on an evaluation of health concerns;
2. System assessment to determine whether the drinking water supply
(from source through treatment to the point of consumption) as a
whole can deliver water that meets the health-based targets;
3. Operational monitoring of the control measures in the drinking water
supply that are of particular importance in securing drinking water
safety;
4. Management plans documenting the system assessment and
monitoring plans and describing actions to be taken in normal
operation and incident conditions, including upgrade and
improvement, documentation and communication; and
5. A system of independent surveillance that verifies that the above are
operating properly.

A key goal of the framework is to make sure that safety of drinking water is
not based solely on end product testing. The health-based targets constitute
the basis for the rest of the work and they should be established by a high-
level authority in collaboration with water suppliers and affected
communities. When the health-based targets are being established a valuation
must be done of what is a tolerable risk. In the guidelines four different
principal types of health-based targets are presented: health outcome targets,
water quality targets, performance targets, and specified technology targets. All four
types aim to protect and improve public health. According to the guidelines

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the health-based targets must take account of the importance of ensuring
access to water.

The system assessment, operational monitoring and management plans constitute
what is called Water Safety Plans (WSPs). A WSP is guided by the health-
based targets and overseen through surveillance. The relationship is
described in Figure 10. Surveillance is supposed to complement the quality
control function of the drinking water supplier and should be conducted by
an independent agency and include all aspects of safety.


Figure 10. Framework for safe drinking water (WHO, 2005).

The WSPs are described as means of ensuring the safety of a drinking water
supply through the use of a comprehensive risk assessment and risk
management approach that encompasses all steps in the water supply from
catchment to consumer (WHO, 2004). Principles and concepts from in
particular the multi-barrier approach and the HACCP system have been used
when developing the WSP approach.

The system assessment is meant to determine if the system is capable of
delivering drinking water that meets the health-based targets. If the
assessment finds that the system theoretically is capable of meeting the
health-based targets, monitoring is the next step in ensuring that it actually
meets the targets. If the system is not able to meet the health-based targets it
has to be modified in some way to meet the targets. When the assessment is
carried through it is important that all parts of the drinking water system are
considered concurrently and that interactions and influences between each
part and their overall effect are taken into consideration (WHO, 2004).

The operational monitoring aims to assess control measures in order to
ensure that the drinking water system is operating properly. A control
measure is an action that serves to reduce or eliminate contamination and is
identified during the system assessment. The applied control measures in a
system should together ensure that the drinking water meets the health-based
targets.

Framework for Safe Drinking-Water
Water Safety
Plans
Independent
Surveillance
Health Based
Targets
Operational
Monitoring
System
Assessment
Management plans,
Documentation and
communication

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The purpose of the management plans are to document and communicate all
information regarding the management of drinking water quality. A
management plan includes for example information regarding the system
assessment and operational monitoring, and it also describes actions in both
normal operation and during situations where control of the system is lost.

The key steps in developing a WSP are described in Figure 11.


Figure 11. Key steps in developing a Water Safety Plan (WHO, 2004).

The definition of a hazard used by WHO, a biological, chemical, physical or
radiological agent that has the potential to cause harm, is very similar to the one
given in the description of HACCP. Since the principles of HACCP have been
used when developing the WSP approach, this is quite natural. To prioritize
and distinguish between important and less important hazards or hazardous
events WHO propose the use of a risk matrix. In Figure 12 an example of a
risk matrix from WHO (2005) is illustrated. Note that this matrix indicates
Assemble the team to prepare the
water safety plan
Document and describe the system
Undertake a hazard assessment and risk
characterization to identify and understand how
hazards can enter into the water supply
Assess the existing proposed system (including a
description of the system and a flow diagram)
Identify control measures – the means by which
risks may be controlled
Define monitoring of control measures –
what limits define acceptable performance and
how these are monitored
Establish procedure to verify that the water
safety plan is working effectively and will meet
the health-based targets
Develop supporting programmes
(e.g., training, hygiene practices, standard operating
procedures, upgrade and improvement, research
and development, etc.)
Prepare management procedures
(including corrective actions) for normal
and incident conditions
Establish documentation and
communication performance

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that comparatively high risk levels may be tolerable, e.g. that cases of
morbidity in the exposed population due to water consumption may be
tolerable every year.

Severity of consequences
Likelihood Insignificant Minor Moderate Major Catastrophic
Almost certain
H
H
E
E
E
Likely
M
H
H
E
E
Moderate L
M
H
E
E
Unlikely L L
M
H
E
Rare L L
M
H
H

Note: The number of categories should reflect the need of the study.
E – Extreme risk, immediate action required; H – High risk, management attention needed;
M – Moderate risk, management responsibility must be specified; L – Low risk, management by
routine procedures.

Examples of definitions of likelihood and severity categories that can be used in risk scoring
Item Definition
Likelihood categories


Almost certain Once a day

Likely Once per week

Moderate Once per month

Unlikely Once per year

Rare Once every 5 years

Severity categories


Catastrophic Mortality expected from consuming water
Major Morbidity expected from consuming water
Moderate
Major aesthetic impact possibly resulting in use of
alternative but unsafe water sources
Minor
Minor aesthetic impact causing dissatisfaction but not
likely to lead to use of alternative less safe sources
Insignificant No detectable impact

Figure 12. Example of a risk matrix and definitions of likelihood and severity categories to be
used in risk scoring in WSP (WHO, 2005; AS/NZS, 1999). Classes of relative risk tolerability
are shown in grey shades.

3.1.4 The Water Framework Directive
The Water Framework Directive (2000/60/EC) is based on natural river basin
districts and the purpose is to protect freshwater resources in order to reach a
sustainable water use (European Commission, 2000b). Within each river basin
all impact on the water environment shall be controlled with the aim to reach
good water status for all European waters by 2015. The directive can be
described as a European strategy on how to manage freshwater resources, the
first part of the drinking water system.

3.1.5 Integrated Water Resources Management
Integrated Water Resources Management (IWRM) has according to Agarwal
et al. (2000) not been clearly defined but can be described as a process which
assists countries in their effort to deal with water issues in a cost-effective and
sustainable manner. Al Radif (1999) points out sustainability of water

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resources, water policy and integrated management, and management of the
resource as key elements in IWRM. The catchment approach characterises
IWRM (Nakamura, 2003) and hence the part of a drinking water system
considered in IWRM is the source water.

3.1.5.1 Agenda 21
Agenda 21 were adopted at the United Nations Conference on Environment
and Development held in Rio de Janerio, Brazil, 1992. Agenda 21 is a
comprehensive programme dealing with sustainable development and the
protection of quality and supply of freshwater resources is just one part of
what Agenda 21 considers. A holistic management of water resources is
emphasized in order to ensure long-term development (United Nations,
1992). It is also pointed out that water resources development and
management should be planned in an integrated manner based on the
principle of sustainability and it should prevent and mitigate hazards.

3.2 Examples on national guidelines
3.2.1 EU - The Directive on the Quality of Water (“Drinking water directive”)
The objective of the Council Directive (98/83/EC) on the quality of water
intended for human consumption is to protect human health from the adverse
effects of any contamination of water intended for human consumption by
ensuring that it is wholesome and clean (European Commission, 1998).
Because drinking water is very important for human health, essential quality
standards which drinking water must comply with have been compiled. The
parametric values, which are based on scientific knowledge and the
precautionary principle, should ensure that drinking water can be consumed
safely on a life-long basis, and thus represent a high level of health protection. It is
also emphasized that appropriate water-protection measures should be
applied to ensure that surface and groundwater is kept clean. The work
should safeguard and promote a sustainable use of drinking water.

There is an ongoing project (“Support for the Development of a Framework
for the Implementation of Water Safety Plans in the European Region”)
funded by the European Commission (EC) related to the planned revision of
the Drinking Water Directive (98/83/EC). As a part of this project the status
of implementation of WSPs in water services of the EU Member States and
other European countries is revealed and the project also gives guidance to
the EC on revison of the directive.

3.2.2 Switzerland
The safety of drinking water supply is controlled through food legislation in
Switzerland. To develop HACCP in all food industry (including drinking
water supply) is obligatory in Switzerland. WSP legal based implementation
(based on HACCP principles) started in 1995.



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Main legal acts relevant to drinking water are:
- Federal Act on Water Protection (source protection zones)
- Federal Act on Foodstuff
- Ordinance on Drinking Water and Natural Mineral Water
- Ordinance on Hygiene
- Cantonal ordinances

Swiss Water and Gas Association (SVGW) produced guidelines for simple
quality assurance system for water supplies (the first edition in 1997, the
second in 2003).

3.2.3 Germany
The content of this section is taken from Sturm et al. (2006). In Germany,
numerous laws and ordinances form the legal basis of the public drinking
water supply. They include for instance the Drinking Water Ordinance
(Trinkwasser-verordnung), the Infection Protection Act
(Infektionsschutzgesetz) and the Water Management Act
(Wasserhaushaltsgesetz). The Drinking Water Ordinance refers to the
generally acknowledged rules of technology (state-of-the-art technology) and
thus to the DVGW (2006) (Technical and Scientific Association for Gas and
Water) System of Technical Standards and corresponding European and
German standards. It has to be pointed out that in Germany special attention
is paid to resource protection. Apart from the relevant DVGW Technical
Standards, the state measures and legal regulations regarding water pollution
control and groundwater protection have to be mentioned. They altogether
serve the protection of the raw water sources.

German water supply has a long-standing tradition in technical self-
regulation concerning the field of technical or hygienic safety and quality
management based on the principle of precaution. The objectives are often
described as multi-barrier approach that combines resource protection with a
high standard in technical and hygienic safety in water abstraction, treatment,
storage and distribution, see Figure 13.


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Figure 13. Multi-barrier approach in German water supply (Sturm, 2006).

The DVGW, as the technical scientific association in the field of water, has
already for decades been compiling practical and scientifically based
Technical Standards for all areas of water supply, which are recommended to
the water suppliers for implementation. The DVGW System of Technical
Standards describes the state-of-the-art technology concerning safety and
reliability in water supply. The draft standards (codes of practice, Technical
Guidelines and Recommendations) are established by working groups of
scientists and experts from industry and public authorities. Draft Standards
are published for public comment, and all comments are reviewed before
final publication. Published Standards are reviewed regularly for continuing
relevance, guaranteeing the integration of latest insights, experience and
technical-scientific progress.

The system of Technical Standards published by DVGW includes more than
300 Codes of Practice, Technical Guidelines, and Recommendations. Several
of them are incorporated in the German standards set up by the German
Institute for Standardization. Besides these standards there are Technical
Guidelines and rules published by other national water supply associations
like the Association for Drinking Water from Reservoirs (ATT) or the German
association for Water, Wastewater and Waste (DWA). However, they are not
designed to regulate every aspect in detail, like a treatment step or a
monitoring system, but to provide recommendations and to outline
principles. On this basis the technical and hygienic safety in the entire supply
chain can be assured.

The system of Technical Standards is complemented by the so called
Technical Safety Management (TSM). TSM is a voluntary management
measure to guarantee the correct implementation of the Technical Standards
(see Figure 14). The main target of the Technical Safety Management is to
support supply companies in legal certainty of its operational processes. To

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guarantee a safe and hygienic water supply the requirements must be
fulfilled to the organisational and staff qualifications in the company. The
application of the Technical Safety Management in the water supply company
is controlled by external consultants. The TSM inspection certificate
documents the success of this process and the fulfilment of requirements of
technical safety.

Figure 14. Technical Safety Management and the system of Technical Standards (Sturm et al.,
2006)

3.2.4 UK – Yorkshire water
The United Kingdom has in many environmental and health issues stressed
the importance of economic valuation as part of the basis for prioritisation of
efforts; see e.g. the UK Treasury Green Book (2003). The Yorkshire Water
utility, owned by the Kelda Group, is well-recognized in the UK and
internationally for performing efficient risk management where explicit
economic risk valuation is an integral part. Yorkshire Water has managed to
increase water safety and simultaneously decreasing the water tariffs for
consumers, by implementing a well-structured risk management framework
based on cost-benefit analysis. Decisions regarding water safety issues are
made with respect to the costs for implementing actions to reduce risks
compared to the changes in risk level, the number of people affected by the
risk, and their willingness to pay for reducing or avoiding the risk (Smith,
2005). The approach is similar in scope to the approach suggested by
TECHNEAU in WP 4.4 (see TECHNEAU, 2005).

3.2.5 Denmark
The Danish Water and Waste Water Association (DWWA) has developed
guidelines for water safety based on the WSP and HACCP principles
(DANVA, 2006). The approach includes the complete drinking water system
from source to tap, including private installations.

The guidelines focus on doing things as simple as possible making it practical
also for smaller water companies to carry out the analysis. Lately the number
of water utilities (municipalities) in Denmark has been reduced from 271 to
98. A threshold for minimum size of the municipality is about 20 000
inhabitants.

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3.2.6 Sweden
The Swedish Water and Wastewater Association (SWWA) have in
collaboration with the National Food Administration prepared a guidance
document on how to apply the HACCP principles to drinking water
production and distribution (SWWA, 2005). The purpose of the document is
to help the water suppliers to include and make the HACCP approach a part
of today’s surveillance work. Even though many water suppliers have not
started to apply the HACCP approach yet, it is becoming more frequently
used in Sweden.

3.2.7 Norway
In 2003 a national investigation pointed out that the water industry in
Norway were lacking guidelines on how to carry out Risk and Vulnerability
Analysis (RVA). In 2006 new guidelines were published (Mattilsynet, 2006)
that focus on identifying events, to rank the undesired events with respect to
risk and to assess need for risk reducing measures. The chosen approach was
not based directly on WSP/HACCP principles e.g. identifying critical control
points are not included. In Norwegian legislation, systems for internal control
(IKmat) are required and these systems include the documentation which is a
part of the HACCP approach. The internal control systems are sometimes
nationally referred to as HACCP light.

3.2.8 The Netherlands
In the Netherlands, EU regulations for drinking water quality are endorsed,
thus forming the basis of the health based targets. Since the new Drinking
Water Decree was issued in the Netherlands in 2001, water companies using
surface water or groundwater at risk of contamination with pathogens are
required to quantitatively assess whether the infection risk of the finished
water meets the standard. To guarantee that infrastructure and operation
(automated and manual) comply with design criteria, pilot audits are
conducted to assess whether systems are implemented to manage these
processes. These audits of the quality system are conducted similar to
HACCP audits, although the audit is not just focusing on the critical risk
control points. Water companies evaluate all risk management systems, as
they are striving to maintain a quality level that, at acceptable costs, should
even prevent once in a life time contamination events. A special tool has been
developed to guarantee a systematic evaluation and documentation of
existing hazards and the risk management systems (control measures). The
tool called MaRiskA combines features of HACCP with features of FMEA
(Failure Mode and Effect Analysis).

Dutch water companies apply an analysis for the vulnerability of supply
(referred to as ‘Leveringsplan’). All elements of the supply chain are checked
in order to ensure that if they fail, water is still supplied in sufficient
quantities. Dutch water companies are executing an analysis to check whether
distribution mains could cause risks to external objects (dykes, roads,
railways, etc). This is a results of the incident occurred at Stein at February

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2004. In addition to this all water companies perform actions against
terrorism.

3.2.9 USA
The main federal law directed at protecting the drinking water quality in
United States is the Safe Drinking Water Act (SDWA, 1996). The United States
Environmental Protection Agency (US EPA) is authorized by the SDWA to set
health-based standards for drinking water quality and to oversee the
implementation by states, localities, and water suppliers. The SDWA is based
on a multiple barrier approach including source water protection, treatment,
distribution system integrity, and public information. This means that the
entire supply system, from source to tap, is considered.

To protect areas serving as public sources of drinking water the states are
required to develop Source Water Assessment Programs (SWAP). A SWAP
intend to (US EPA, 1997):
- identify the areas that supply public tap water;
- inventory of contaminants and assess water system susceptibility to
contamination; and
- inform the public of the results.

The aim is to use the assessment results when implementing Source Water
Protection Programs.

Since the September 11, 2001, attacks on World Trade Center in New York, a
deliberate contamination intrusion to a water distribution system is now
considered one of the most serious threats to public health in the United
States (Ostfeld and Salomons, 2005). As a consequence of this the security of
United States drinking water and wastewater infrastructures has become a
top priority. The Bioterrorism Act (2002) requires that drinking water utilities
serving more then 3,300 persons conduct a vulnerability assessment. The
assessments should help the water utilities to identify and evaluate potential
threats and identify risk reduction options. An emergency response plan
describing the actions that a drinking water utility would take in response to
a major event also has to be complied.

The description above is based on the federal legislation, the implementation
by different states may differ and individual states may have additional, more
stringent, rules.

3.2.10 The Canadian Multi-Barrier Approach
To use multiple barriers when managing risks is a common approach and
often included in other approaches. However, the Canadian Council of
Ministers of the Environment (CCME, 2004) has described how the multi-
barrier approach can be applied to drinking water supplies, see Figure 15. The
multi barrier-approach is described as an integrated system of procedures,
processes and tools that collectively prevent or reduce the contamination of

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drinking water from source to tap, in order to reduce risks to public health.
The approach is based on the implementation of multiple barriers throughout
the drinking water system, from source to tap. The barriers are supposed to
block or control microbiological pathogens and chemical contaminations that
may enter the supply system. Since multiple barriers are used the failure of
one or more barriers can be compensated by the remaining barriers. The
barriers can be physical like a filter or they can be processes or tools linked to
the overall management, e.g. training and education.

Clean, safe,
reliable
drinking
water
Source
water
protection
Drinking
water
treatment
Drinking water
distribution
system
Management
Monitoring
Legislative
and policy
frameworks
Guidelines,
standards and
objectives
Public involvment
and awareness
Research, sience and
technology
Clean, safe,
reliable
drinking
water
Source
water
protection
Drinking
water
treatment
Drinking water
distribution
system
Management
Monitoring
Legislative
and policy
frameworks
Guidelines,
standards and
objectives
Public involvment
and awareness
Research, sience and
technology

Figure 15. The Multi-Barrier Approach (CCME, 2004).

3.2.11 Australian framework
In the Australian Drinking Water Guidelines (ADWG) it is stated that safe
drinking water is essential for life and it is therefore of great importance that
the safety is assured (NHMRC/NRMMC, 2004). It is also emphasized that a
preventive management approach that consider all steps in water production,
from catchment to consumer, is the best way to manage the risks to drinking
water systems. According to the ADWG drinking water should be safe to drink
for people in most stages of normal life, including children over six months of age and
the very old. The water is safe to drink when it does not contain any harmful
concentrations of chemicals or pathogenic micro-organisms. It is also stated
that ideally the drinking water should be aesthetically pleasing in regard to
appearance, taste and odour.

In the ADWG a framework for management of drinking water quality is
presented. The framework is according to Rizak et al. (2003) supposed to
provide a comprehensive and preventive strategy from catchment to
consumer. Some parts of the framework are based on the HACCP system as
well as the two management systems ISO 9001 (Quality Management) and
AS/NZS 4360 (Risk Management). Figure 16 is adapted from the risk
management standard and is a flowchart illustrating the relation between the
activities of the risk assessment process. The flowchart in Figure 16 and the
illustration of the risk management process in Figure 4 are very similar.

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Figure 16. Relation between activities of the risk assessment process (AS/NZS 4360:2004).

The framework for management of drinking water quality presented in the
ADWG consists of four key areas: commitment to drinking water quality
management, system analysis and management, supporting requirements, and
review. The four areas and the connection between them are described in
Figure 17.

No
Start
Hazard
Identification and
Context definition
Is risk
acceptable
?
Risk
Estimation
Risk
Treatment
Risk
Evaluation
End
Yes
Risk
Criteria
Communicate and consult
Monitor and review

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Figure 17. The ADWG framework for management of drinking water quality
(NHMRC/NRMMC, 2004).

It is important that senior executives as well as the entire organisation show
commitment to drinking water quality management. Organisational support
and long-term commitment is described as a basic requirement to reach an
effective management system. When analysing and managing the water
supply system, hazards as well as preventive measures should be identified.
When doing this it is important that the entire system is understood. The
assessment of the drinking water supply system is divided into water supply system
analysis, assessment of water quality data and hazard identification and risk
assessment. To distinguish between high and low risks the use of a risk matrix
is proposed in the ADWG. The proposed risk matrix is similar to the one
proposed by WHO (2004), see Figure 12. The importance of using a multi-
barrier approach is emphasizes in the ADWG as a part of the preventive
measures for drinking water quality management. The protection of source water
is considered as the most effective barrier since it is the first part of the
system. Another part of the preventive measures is the application of critical
control points, based on the HACCP approach.

To make sure the management system is working properly a review
including evaluation and audit processes are suggested. The review should
make it easier to continually improve the work. The communication and
involvement of the consumers is also pointed out as an important aspect of
the management work. The expectations of the community and the
willingness to pay should be used as a basis when making decisions.

According to Sinclair and Rizak (2004) compliance monitoring is often used
by regulatory structures as a mean to manage drinking water quality.
Compliance monitoring, however, has major limitations and are by it self not
an efficient manner to manage drinking water quality. An example is that
Escherichia Coli or thermotolerant coliforms that are used as indicator
organisms when assessing microbiological water quality do not give a good
measure of the risks from viruses and protozoa (Sinclair and Rizak, 2004).
Even though the compliance monitoring has some limitation it is of great
Commitment to Drinking Water Quality Management

System Analysis and Management
Assessment of the drinking water supply
system
Preventive measures for drinking water
quality management
Operational procedures and process
control
Verification of drinking water quality
Management of incidents and
management

Supporting Requirements
Employee awareness and training
Community involvement and awareness
Research and development
Documentation and reporting
Review
Evaluation and audit
Review and continual
improvement


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importance when managing water quality. When applying the framework
presented in the ADWG the compliance monitoring is supposed to be viewed
in a proper perspective (Sinclair and Rizak, 2004).

3.2.12 New Zealand Public Health Risk Management Plan
In New Zealand compliance criteria for water leaving the treatment plant and
the distributions system are presented in the Drinking Water Standards for
New Zealand (DWSNZ) by the Ministry of Health (2005a). The DWSNZ can
be used to verify the quality of the water delivered to the consumers but is
not enough to protect the public health against risks from contaminated
drinking water. To be able to do this the use of a Public Health Risk
Management Plan (PHRMP) is emphasized. The PHRMP is described by the
Ministry of Health (2005a) as a management tool for suppliers that will aid
them to identify, manage and minimise events that could cause water quality
to deteriorate. The DWSNZ as well as the PHRMP focus on health related
risks and microbial contaminants are considered the most severe.

How to prepare and develop a PHRMP is described by the Ministry of Health
(2005b) and a lot of guidance material is available on the Ministry of Health
webpage (www.moh.govt.nz). In Figure 18 the main steps when developing a
PHRMP are presented and in Figure 19 the main steps when using the
PHRMP are presented. The so called guides mentioned in Figure 18 are
documents, specific for different supply elements, describing causes of an
event, preventive measures, how to check preventive measures, and
corrective actions.


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Figure 18. Main steps when developing a PHRMP (Ministry of Health, 2005b).

In Figure 18 the steps that have to be performed and the result that should be
added to the PHRMP is illustrated. The work can simplified be described as a
process that starts with getting to know the system and identifying barriers as
well as hazards, preventive measures and corrective actions. This information
is later used to identify necessary improvements and in which order they
should be accomplished. The process illustrated in Figure 19 describes how
the PHRMP should be used when it has been developed. It is a continuous
work that aims to increase the safety.

Produce an overview of your supply and
decide which Public Health Risk
Management Plan Guides are needed.
Step Add to your PHRMP
Identify the barriers to contamination your
supply has.
Use the Guides to identify events that may
introduce hazards into the water.
Use the Guides to identify:
• possible causes of each event
• preventive measures to avoid each event
• corrective actions to use if preventive
measures fail.
Decide where improvements in your supply
should be made.
Decide on the order in which improvement
will be made.
Draw up a timetable for making the
improvements.
Note links to other quality assurance
systems.
Use the Guides to prepare Contingency
Plans.
Use the Guide to prepare instructions for
checking that your Plan is working properly
- Performance Assessment
Decide on communication policy and needs.
Flow diagram of your supply
Checklist of barriers present
Risk information Table for your
supply
Improvement Schedule listing:
• improvements needed
• their levels of importance
• a time table for their introduction
• responsibility
Note of other quality assurance
systems and their links with the Plan.
Set of Contingency Plans for each
supply element.
Set of instructions for review of the
performance of the Plan.
Set of instructions for reporting.

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Figure 19. Steps when using the PHRMP (Ministry of Health, 2005b).

3.3 Comparison and discussion
When comparing the different strategies and frameworks a couple of
similarities can be identified. It is pointed out in many documents that
drinking water is essential to humans and it is also stated that it is of
importance to the economic development. Since drinking water is essential to
humans it is obvious that it has to be available in sufficient quantities and safe
to drink. In the EU directive on the quality of water, the WHO guidelines, and
the Australian guidelines, it is stated that safe drinking water means that the
water can be consumed over a life-long period without posing any significant
health risk. It is also emphasized that the different sensitivities that may occur
between life stages are taken into account. The main focus is on health related
risks and it is stated that microbial contamination of drinking water is the
most severe risk. Little attention is paid to water quantity and technical risks
related to the ability to deliver water to the consumers. The IWRM and Water
Framework Directive are the two strategies that focus on water resources and
thereby in a clear way emphasize the importance of protecting the source
water.

It is of great importance that the drinking water can be delivered to the
consumers and that it is safe to drink, but as stated in for example the Bonn
Charter the water also needs to have an aesthetic good quality. Primarily this
means that the water should have an acceptable taste and odour. However,
the Australian guidelines advocate the importance of having a safe drinking
water rather than an aesthetically good quality. However, if the water does
not taste or smell good, people are probably not going to drink it.
Refer to the improvement Schedule prepared
in your Plan.
Step
Follow the timetable of the Schedule, put in
place:
• preventive measures
• checks
• corrective actions that are needed, but not
already present.
Review information gathered by monitoring
and maintenance programmes.
Refer to and use the Contingency Plans
should this be necessary.
Review how well the Plan is working and
make changes where necessary.

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The weakness of compliance monitoring is described in many strategies and
frameworks, and it is suggested that it is used as a complement and not
exclusively to guarantee a safe drinking water. Instead of relying on end-
product testing a holistic approach considering risks from source to tap or,
more extensively, from catchment to consumer is emphasized. Another
element that is described in the strategies and frameworks is the importance
of co-operation between stakeholders. The Australian guidelines also
emphasize that the expectations of the community and the willingness to pay
should be taken under consideration when making decisions.

The application of barriers is clearly advocated in the Canadian guidance but
the concept is also emphasized in e.g. the WHO guidelines, the New Zealand
PHRMP and the Australian guidelines. In the Canadian guidance it is clearly
stated that the barriers do not have to be physical barriers or barriers that
directly prevent contaminants to enter the system; also training and education
are important elements. The multi-barrier approach is commonly used when
managing risks of different kinds to various systems and clearly the approach
is also applicable to drinking water systems.

An interesting question is what range of application the HACCP system has
in the drinking water system. According to Havelaar (1994) several steps in
the system are important to assure the quality of the final water, but cannot
be considered as CCPs under the responsibility of the water producer because
of a lack of a direct control. According to the Australian guidelines
(NHMRC/NRMMC, 2004) HACCP is aligned quite readily on the treatment
component of drinking water supply and may not as easily be applied to the
important areas of catchment and distribution system. Also Hrudey (2004)
emphasize that the principles of HACCP are most readily applied to the
operational control of treatment process. This indicates that some changes are
necessary to be able to apply HACCP to the entire drinking water system,
from source to tap.

When the WSP approach was developed principles and concepts from the
HACCP system were used. The WSP approach can be described as a way of
adapting the HACCP approach to drinking water systems. When comparing
the figures illustrating the different steps in the two approaches close points
of similarities can be identified. Since the framework for management of
drinking water quality presented in the Australian guidelines also to some
extent is based on the HACCP approach, similarities can be found between
the Australian framework and HACCP as well as the WSP approach. The
development and use of a so called PHRMP, described by the New Zealand
Ministry of Health, also has similarities to the frameworks mentioned above.
The work can be described as a process that starts with getting to know the
system and identifying barriers as well as hazards, preventive measures and
corrective actions. These components of the working procedure are similar to
the ones that can be found in e.g. the WSP approach.

When comparing the steps in developing a WSP with the general risk
management process, similarities as well as differences can be identified. First

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of all a WSP has a specific intended use, drinking water systems, and is
focused on risks related to human health. The risk management process on
the other hand is general and illustrates which key steps have to be
performed when managing any type of risk. In WHO (2005) the development
of a WSP is illustrated somewhat different than in the guidelines (WHO,
2004), see Figure 20. From Figure 20 it can be clearly seen that the supporting
programmes are supposed to be available to all other steps. It is also more
clearly illustrated that the work should be reviewed and continuously
updated when new information is available.


Figure 20. Steps in the development of a WSP (WHO, 2005).

To illustrate the similarities and the differences between WSP and the risk
management process a comparison is made in Figure 21. In Figure 21 the
steps in WSP, presented in Figure 20, have been compared to the different
parts of the risk management process described in Chapter 2. The first step in
the WSP development is to assemble a team. This step is part of the
preparatory work and can be illustrated as something that is done before the
risk management work begins or it can be included as part of the scope
definition. However, it is of great importance that the team working with risk
management has all the required knowledge and hence people from different
parts of the organisation should be included as well as people from outside
the organisation if necessary. The reason scope definition is not viewed as a
separate step in WSP is most likely because it is understood that a WSP is
focused on health risks related to drinking water. If the scope definition is
included this broadens the field of application and makes it easier to include
also other kind of risks.
Assemble team
Describe water supply
Conduct hazard analysis
Identify control measure
Define operational limits
Establish monitoring
Establish corrective actions and incident response
Establish record keeping
Validation and verification
Supporting
Programmes
Reviewing
Experience
and Future
Needs
Review,
approval
and audit

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The second step in WSP, the description of water supply, can be described as
part of the scope definition and the hazard identification. To be able to
perform the hazard identification it is necessary to have knowledge about the
system and the description of the supply system is part of the documentation
of the work. The hazard analysis in WSP (third step) includes the hazard
identification and the risk estimation. In the description of WSP in Figure 11
the terms hazard assessment and risk characterisation are used to illustrate
what is called hazard analysis in Figure 20. The separation of hazard analysis
into hazard assessment and risk characterisation is more similar to the steps
in the risk management process.

The reason risk tolerability decision is not part of WSP is probably because
the WSP work is guided by the health based targets and decisions about
tolerable risk are made when the targets are compiled. To be able to deal with
risks that can not be controlled using predetermined targets, the risk
tolerability decision should be included as a part of the work.

The identification of control measures and definition of operational limits
(fourth and fifth steps in WSP) can be illustrated as part of the analysis of
options, but it is also possible to include them as part of the implementation
and monitoring. The next four steps in WSP have been placed next to
implementation and monitoring. It is hard to distinguish them but they are all
part of the work intended to ensure that everything is working properly and
if something happens corrective actions are taken.

The supporting programmes are supposed to assist the other steps in WSP
and this part is missing in the illustration of the risk management process. It
is also more clearly illustrated in the WSP steps that review and new
information should be incorporated and a part of the feedback loop.


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Figure 21. Comparison between the risk management process and WSP.

Risk analysis
Scope definition






Hazard identification






Risk estimation






Risk evaluation
Risk tolerability decision






Analysis of options






Risk reduction/control
Decision making






Implementation






Monitoring






Assemble team
Describe water supply
Conduct hazard analysis
Identify control measure
Define operational limits
Establish monitoring
Establish corrective actions and incident response
Establish record keeping
Validation and verification
Supporting
Programmes
Reviewing
Experience
and Future
Needs
Review,
approval
and audit

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