AN INVESTIGATION INTO OPTIMISING WATER 
FLOW OF INDUSTRIAL SYMBIOSIS: DEVELOPMENT 
AND APPLICATION OF A MODEL 
 
 
 
 
Bhadra Harshini Mallawaarachchi 
 
(198001C) 
 
 
Degree of Doctor of Philosophy 
 
 
Department of Building Economics, University of Moratuwa, Sri Lanka  
and  
School of Architecture and Built Environment, Deakin University, 
Australia 
 
 
October 2022 
 AN INVESTIGATION INTO OPTIMISING WATER 
FLOW OF INDUSTRIAL SYMBIOSIS: DEVELOPMENT 
AND APPLICATION OF A MODEL 
 
 
 
 
Bhadra Harshini Mallawaarachchi 
 
(198001C) 
 
 
Thesis submitted in partial fulfilment of the requirements for the degree 
Doctor of Philosophy 
 
Department of Building Economics, University of Moratuwa, Sri Lanka  
and  
School of Architecture and Built Environment, Deakin University, 
Australia 
 
 
October 2022 
 ii 
DECLARATION  
I declare that this is my own work and this thesis does not incorporate without 
acknowledgement any material previously submitted for a Degree or Diploma in any 
other University or Institute of higher learning and to the best of my knowledge and 
belief it does not contain any material previously published or written by another 
person except where the acknowledgement is made in the text. I retain the right to use 
this content in whole or part in future works (such as articles or books).  
Name of the Student: B.H. Mallawaarachchi 
Signature:         Date: 
 
 
The above candidate has carried out research for the PhD thesis under my supervision. 
I confirm that the declaration made above by the student is true and correct.  
Name of the Supervisors:  
Prof. Y.G. Sandanayake (Principal Supervisor – University of Moratuwa) 
Dr. G. I. Karunasena (Principal Supervisor – Deakin University)  
Prof. Chunlu Liu (Associate Supervisor – Deakin University) 
 
Signature of the Principal Supervisor (University of Moratuwa):     
Date: 
 
 
 
 
 
19.10.2022
Prof. Y.G. Sandanayake
 iii 
ABSTRACT 
An investigation into optimising water flow of industrial symbiosis: 
Development and application of a model 
The concept of Industrial Symbiosis (IS) has obtained world concern as a new 
initiative for achieving collaborative benefits through exchange of resources between 
industries including water. Even though, these initiatives became prominent as 
successful projects in the early stages, many of them have resulted in failures in the 
long term without achieving the expected results due to deficiencies in IS planning. In 
the current process, no prior evaluation and optimisation are taking place before 
implementing the identified water synergies. There is therefore a need to have a 
standardised method to assess the optimum water flow of IS. Accordingly, the current 
study aimed to develop a model to assess the optimum water flow of IS. In order to 
achieve the aim, the research stands within the pragmatism philosophical stance. The 
abductive approach was applied as the appropriate research approach. Sequential 
exploratory research design was adopted consisting three phases: Phase I: Desk study; 
Phase II: Interviews with industry experts; and Phase III: Case study.  Phase I - Desk 
study was conducted to collect and review the data from reliable published sources to 
identify water inputs and outputs of industrial entities. Based on the key literature 
reviewed, the conceptual model was developed by integrating mathematical formulae. 
In Phase II, sixteen interviews were conducted with industry experts in Sri Lanka to 
collect the data. The collected data were analysed using the code-based content 
analysis technique with the application of QSR International’s NVivo. 12. As key 
findings derived from analysis, current methods & issues of industrial water 
management and enablers & barriers for initiating water exchange networks in Sri 
Lanka were identified. Furthermore, the conceptual model and mathematical formulae 
were also refined to the selected context. The applicability and feasibility of the model 
were evaluated during Phase III. An IS network in an export processing zone (EPZ) in 
Sri Lanka, comprising three geographically co-located industrial entities, was selected 
as a suitable case study. Seven semi-structured interviews were conducted with 
professionals within the selected case to collect the data, which were analysed using 
the mixed integer linear programming (MILP) approach. The assessment model was 
developed and tested using SageMath software. Finally, environmental, economic and 
social feasibility of the developed model were also determined. The developed model 
forms a unique foundation for assessing the optimum water flow of IS, applying in any 
context subject to context-specific enhancements. The novelty of the current research 
is its objective of reducing freshwater consumption of the IS network through 
maximum wastewater recovery in assessing the optimum water flow of IS. Thus, the 
research outcomes provide a role model for all developed and developing countries for 
reducing the environmental impact of industrialisation through optimum water sharing 
between industrial entities. 
Key Words: Industrial Symbiosis, Mathematical Programming, Optimisation 
Modelling, Optimum Water Flow, Water Network 
 iv 
DEDICATION 
 
 
 
 
 
 
I dedicate this piece of work to my beloved family who encouraged me, with 
emotional and spiritual effort in this endeavour… 
 
  
 v 
ACKNOWLEDGEMENT 
This research has been supported by a number of individuals with their utmost guidance and 
encouragement. I would like to acknowledge their appreciated contribution and to convey my 
gratitude to every one of them. 
First and foremost, I would like to express my sincere gratitude to Prof. Y.G. Sandanayake 
(Head, Department of Building Economics), Dr. G.I. Karunasena and Prof. C. Liu for their 
thoughtful guidance, assistance and encouragement provided by being my research 
supervisors. You converted me to an improved version as a researcher as well as an academic.   
Second, my heartfelt gratitude goes to Prof. Lalith de Silva, Professor, Department of Building 
Economics, University of Moratuwa; Prof. Dileeka Dias, Former Dean, Faculty of Graduate 
Studies, University of Moratuwa, Prof. Baskaran, Associate Dean (International and 
partnerships), Prof. Anthony Mills, Former Head, School of Architecture and Built 
Environment, Deakin University, Australia and Dr. Thanuja Ramachandra, Former Director – 
Faculty Higher Degrees Committee, Faculty of Architecture for initiating this Joint PhD 
program between Deakin University, Australia and University of Moratuwa, Sri Lanka. It was 
a greater opportunity to harvest new knowledge and research experience in two different 
research environments. 
I also extend my gratitude to Prof. Ajith de Alwis, Dean, Faculty of Graduate Studies, 
University of Moratuwa, Dr. Dominic Ahiaga-Dagbui and Dr. Sanja Roods, Higher Degree 
Research (HDR) Coordinators, School of Architecture and Built Environment, Helen 
Woodball, Manager International Research Training and the Faculty Coordinators of the 
Faculty of Science, Engineering and Built Environment and HDR Advisors of Graduate 
Research Academy – Deakin Research, Deakin University, Australia, for their unfailing 
assistance and guidance. Furthermore, Ch.QS. Mr. H.S. Jayasena, Former Head of the 
Department, the Research Coordinators, my colleagues and other academic & non-academic 
staff members of the Department of Building Economics are also acknowledged for their kind 
assistance.  
The greatest thanking thoughts convey to my research advisors, Prof. Thayaparan Gajendran 
and Dr. N.G.R. Perera for their valuable comments given by directing this research towards 
success. I further express my heartiest thanks to all the professionals in industry and academia 
who gave their immense contribution and editorial assistance during this research. 
Finally, an immeasurable thanks of all must go to my beloved husband, mother, father, my 
little son, daughter and my nursemaid who supported unconditionally by being with me 
patiently. 
 
 
 
 
 
 
 vi 
TABLE OF CONTENT 
 
DECLARATION ....................................................................................................... II 
ABSTRACT ............................................................................................................. III 
DEDICATION .......................................................................................................... IV 
ACKNOWLEDGEMENT ........................................................................................ V 
TABLE OF CONTENT ........................................................................................... VI 
LIST OF FIGURES ................................................................................................. IX 
LIST OF TABLES ................................................................................................... XI 
LIST OF EQUATIONS ........................................................................................ XIII 
LIST OF ABBREVIATIONS .............................................................................. XIV 
LIST OF APPENDICES ...................................................................................... XVI 
LIST OF PUBLICATIONS AND AWARDS ................................................... XVII 
CHAPTER 1: INTRODUCTION TO THE RESEARCH ..................................... 1 
1.1 RESEARCH BACKGROUND ................................................................................... 1 
1.2 RESEARCH PROBLEM STATEMENT AND RATIONALE ........................................... 3 
1.3 RESEARCH AIM AND OBJECTIVES ........................................................................ 6 
1.4 RESEARCH METHODOLOGY ................................................................................. 6 
1.5 SCOPE AND LIMITATIONS .................................................................................... 8 
1.6 SIGNIFICANCE OF THE RESEARCH ........................................................................ 9 
1.7 STRUCTURE OF THE THESIS ............................................................................... 10 
1.8 CHAPTER SUMMARY ......................................................................................... 10 
CHAPTER 2: LITERATURE REVIEW ............................................................... 12 
2.1 INTRODUCTION .................................................................................................. 12 
2.2 CONCEPT OF INDUSTRIAL WATER MANAGEMENT (IWM) ................................. 12 
2.2.1 The need of water for industries ............................................................... 12 
2.2.2 Issues in obtaining water for industries .................................................... 13 
2.2.3 Wastewater discharge and related issues in industrial systems ............... 14 
2.2.4 Industrial water management (IWM) ........................................................ 15 
2.3 THE CONCEPT OF INDUSTRIAL SYMBIOSIS (IS) ................................................. 21 
2.3.1 Evolution of industrial symbiosis concept................................................. 21 
2.3.2 Industrial symbiosis in the context of circular economy ........................... 24 
2.3.3 Definitions of industrial symbiosis ............................................................ 25 
2.3.4 Fostering industrial symbiosis .................................................................. 29 
2.3.5 Initiating procedure of industrial symbiosis systems ................................ 33 
2.4 RESOURCE EXCHANGE IN INDUSTRIAL SYMBIOSIS ............................................ 35 
 vii 
2.5 WATER FLOW OF INDUSTRIAL SYMBIOSIS: THE GLOBAL CONTEXT .................. 38 
2.6 INDUSTRIAL WATER MANAGEMENT (IWM) IN SRI LANKA ............................... 41 
2.7 CHAPTER SUMMARY ......................................................................................... 43 
CHAPTER 3: RESEARCH METHODOLOGY .................................................. 44 
3.1 INTRODUCTION .................................................................................................. 44 
3.2 RESEARCH DESIGN ............................................................................................ 44 
3.2.1 Formulate the research problem, aim and objectives ............................... 47 
3.2.2 Literature review ....................................................................................... 47 
3.2.3 Philosophical worldview of the research: Pragmatism stance ................. 47 
3.2.4 Research approach: Abductive approach in theory redevelopment ......... 52 
3.2.5 Research strategy: Sequential exploratory mixed research strategy ........ 55 
3.2.6 Drawing conclusions and making recommendations ............................... 65 
3.3 VALIDITY OF THE RESEARCH............................................................................. 66 
3.4 CHAPTER SUMMARY ......................................................................................... 67 
CHAPTER 4: DEVELOPMENT OF CONCEPTUAL MODEL AND 
MATHEMATICAL FORMULAE (PHASE I) ..................................................... 68 
4.1 INTRODUCTION .................................................................................................. 68 
4.2 OPTIMISATION MODEL DEVELOPMENT PROCESS .............................................. 68 
4.2.1 Input and output water flow ...................................................................... 69 
4.2.2 Step 1 - Data compilation and initial processing...................................... 80 
4.2.3 Step 2 - Optimisation model design and development .............................. 87 
4.2.4 Step 3 - Assessment of the optimal configuration ..................................... 98 
4.2.5 Step 4 - Evaluation of the economic, environmental and social feasibility
 ............................................................................................................................ 99 
4.3 CHAPTER SUMMARY ......................................................................................... 99 
CHAPTER 5: DEVELOPMENT OF A CONTEXT-SPECIFIC MODEL 
(PHASE II) .............................................................................................................. 100 
5.1 INTRODUCTION ................................................................................................ 100 
5.2 THE PROFILE OF INTERVIEWEES AND DEMOGRAPHIC INFORMATION ............... 100 
5.3 DATA COLLECTION AND ANALYSIS ................................................................. 103 
5.4 RESEARCH FINDINGS - INDUSTRIAL WATER EXCHANGE IN SRI LANKA .......... 103 
5.4.1 Existing methods of industrial water management ................................. 103 
5.4.2 Existing issues of industrial water management ..................................... 107 
5.4.3 Enablers and barriers to initiate water exchange networks in Sri Lanka
 .......................................................................................................................... 112 
5.5 RESEARCH FINDINGS - DEVELOPMENT OF A CONTEXT-SPECIFIC ROBUST MODEL 
TO ASSESS THE OPTIMUM WATER FLOW OF IS IN SRI LANKA ............................... 119 
5.5.1 Context-specific model requirements and enhancements of the conceptual 
model ................................................................................................................ 120 
5.5.2 Key variables of the context-specific model ............................................ 122 
5.5.3 Parameters of the context-specific model ............................................... 123 
 viii 
5.5.4 Context-specific model development and testing .................................... 125 
5.6 CHAPTER SUMMARY ....................................................................................... 127 
CHAPTER 6: EVALUATION OF THE APPLICABILITY AND 
FEASIBILITY OF THE CONTEXT SPECIFIC MODEL (PHASE III) ......... 128 
6.1 INTRODUCTION ................................................................................................ 128 
6.2 PROCEDURE ADAPTED IN MODEL EVALUATION .............................................. 128 
6.3 INDUSTRIAL SYMBIOSIS NETWORK OF AN EXPORT PROCESSING ZONE IN SRI 
LANKA: THE CASE STUDY .................................................................................... 128 
6.4 ANALYSIS OF THE CURRENT STATUS OF THE SELECTED CASE STUDY ............ 132 
6.4.1 Current status - Industrial Entity A ......................................................... 132 
6.4.2 Current status - Industrial Entity B ......................................................... 134 
6.4.3 Current status - Industrial Entity C ........................................................ 137 
6.5 INITIATION OF OPTIMUM WATER EXCHANGE NETWORK BETWEEN SELECTED 
INDUSTRIAL ENTITIES ........................................................................................... 141 
6.5.1 Planning of industrial symbiosis and identification of water synergies . 142 
6.5.2 Application of the developed model for assessing the optimum water flow 
of the proposed industrial symbiosis network .................................................. 146 
6.6 ENVIRONMENTAL, ECONOMIC AND SOCIAL FEASIBILITY OF THE PROPOSED 
OPTIMAL NETWORK .............................................................................................. 154 
6.6.1 Environmental feasibility of the proposed optimal network ................... 155 
6.6.2 Economic feasibility of the proposed optimal network (life cycle cost 
analysis) ........................................................................................................... 157 
6.6.3 Social feasibility of the proposed optimal network ................................. 166 
6.7 A WAY FORWARD OF THE DEVELOPED MODEL .............................................. 167 
6.8 UNIQUENESS OF THE MODEL AND GENERALISATION ...................................... 167 
6.9 CHAPTER SUMMARY ....................................................................................... 168 
CHAPTER 7: CONCLUSIONS AND RECOMMENDATIONS ...................... 169 
7.1 INTRODUCTION ................................................................................................ 169 
7.2 OVERALL CONCLUSIONS OF THE RESEARCH ................................................... 169 
7.3 LIMITATIONS OF THE MODEL APPLICATION .................................................... 174 
7.4 CONTRIBUTION TO KNOWLEDGE ..................................................................... 175 
7.5 RECOMMENDATIONS FOR INDUSTRY PRACTITIONERS ..................................... 176 
7.6 RECOMMENDATIONS FOR FURTHER RESEARCH ............................................... 177 
REFERENCES ....................................................................................................... 178 
APPENDICES ........................................................................................................ 196 
 
 
 
 ix 
LIST OF FIGURES 
Figure  Description Page 
Figure 2.1 United Nation’s 17 sustainable development goals 16 
Figure 2.2 General principles for valuing water 18 
Figure 2.3  Drivers and benefits of zero liquid discharge  19 
Figure 2.4 Resource flow in linear and circular industrial systems 20 
Figure 2.5 Conceptual framework of industrial ecology 23 
Figure 2.6  The elements of IE seen as operating at different levels 24 
Figure 2.7 Definitions of industrial symbiosis 26 
Figure 2.8  Industrial symbiosis at Kalundborg, Denmark 30 
Figure 2.9 Key characteristics of self-organising, planned and facilitated IS 31 
Figure 2.10 “3-2 heuristic” criterion 36 
Figure 2.11 The proposed re-development 40 
Figure 3.1 A framework for research design 45 
Figure 3.2 Research design framework 46 
Figure 3.3  Sequential exploratory mixed design of this research 58 
Figure 3.4 Case selection and unit of analysis 63 
Figure 4.1 Optimisation model development process flow chart 69 
Figure 4.2 Water flow network of Kalundborg IS Project, Denmark 72 
Figure 4.3 Water flow network of Choctaw Eco-Industrial Park, USA 73 
Figure 4.4 General water inputs and outputs 79 
Figure 4.5 Water inputs and outputs of a typical industrial entity 80 
Figure 4.6 Selection of industrial entities 82 
Figure 4.7 A typical water input and output flows of an industrial entity 83 
Figure 4.8 Water synergies between participating industrial entities 84 
Figure 4.9 Source-sink relationships between the industrial entities A, B and C 85 
Figure 4.10 Theoretical framework  86 
Figure 4.11 The conceptual model for assessing the optimum water flow of IS 
(before mathematical formulae development) 
92 
Figure 4.12 The conceptual model for assessing the optimum water flow of IS 
(after mathematical formulae development) 
97 
Figure 5.1 Years of experience  101 
Figure 5.2 Areas of expertise 102 
Figure 5.3 Key categories of enablers and barriers (author defined) 113 
Figure 5.4 Enablers for exchanging water among the industries in Sri Lanka 113 
Figure 5.5 Barriers for exchanging water among the industries in Sri Lanka 115 
Figure 5.6 Enablers and barriers for initiating water exchange networks 118 
Figure 5.7 Context-specific model to assess the optimum water flow of 
industrial symbiosis in Sri Lanka 
126 
Figure 6.1 Geographical plan of the selected case study 131 
Figure 6.2 Conventional water network of the selected case study 140 
Figure 6.3 Possible water synergies between selected industries  144 
Figure 6.4 Typical IS based water exchange network in the selected case study 
(proposed) 
146 
Figure 6.5 A screen shot of test results obtained from the SageMath software - 
TWW flow between industries  
150 
Figure 6.6 Optimal water flow network 151 
 x 
Figure 6.7 A screen shot of test results obtained from the SageMath software - 
freshwater consumption  
152 
Figure 6.8 A screen shot of test results obtained from the SageMath software - 
wastewater discharge  
153 
Figure 6.9 Results of sensitivity analysis  165 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 xi 
LIST OF TABLES 
Table Description Page 
Table 2.1 Resources flow of IS projects 38 
Table 3.1 Philosophical assumptions in research 48 
Table 3.2 Characteristics of the research approach  53 
Table 3.3 Rationale for single case study design selected in this research 61 
Table 4.1 Selection of published IS projects for desk study  70 
Table 4.2 Articles availability of the selected cases 71 
Table 4.3 Water inputs and outputs of Kwinana Industrial Area, Australia 74 
Table 4.4 Water inputs and outputs of Qijiang Industrial Park, China 75 
Table 4.5 Water inputs and outputs of Songmudao Chemical Industrial Park, 
China 
76 
Table 4.6 Typical water inputs and outputs of IS networks 78 
Table 4.7 Nomenclatures 94 
Table 4.8 Input and output data extraction 94 
Table 5.1 Profile of interviewees 100 
Table 5.2 Summary of the methods of industrial water management in Sri 
Lanka 
105 
Table 5.3 Summary of the issues of industrial water management in Sri Lanka 108 
Table 5.4 Comparison of the model requirements and enhancements: 
Conceptual vs context specific models 
121 
Table 5.5 Selection of water sources and water sinks in Sri Lankan context 124 
Table 6.1 Criteria adopted in selecting industrial entities in the selected case 
study 
129 
Table 6.2 Details of selected industrial entities 130 
Table 6.3 Profile of interviewees 132 
Table 6.4 Freshwater consumption – Industrial Entity A 133 
Table 6.5 Wastewater generation – Industrial Entity A 134 
Table 6.6 Freshwater consumption – Industrial Entity B 135 
Table 6.7 Wastewater generation – Industrial Entity B 136 
Table 6.8 Freshwater consumption – Industrial Entity C 138 
Table 6.9 Wastewater generation – Industrial Entity C 139 
Table 6.10 Water quality standards for drinking water and wastewater 
discharge 
141 
Table 6.11 Industrial and cooling water requirement of each industrial entity 142 
Table 6.12 Availability of treated wastewater supply of each entity after 
preliminary and secondary treatment 
143 
Table 6.13 Source and sink relationships between entities A, B and C in the 
proposed IS network 
147 
Table 6.14 Limiting water data for water sources  148 
Table 6.15 Limiting water data for water sinks 149 
Table 6.16 Optimal water exchange network 150 
Table 6.17 Reduction of freshwater consumption in the optimal water network  152 
Table 6.18 Reduction of wastewater discharge in the optimal water network  153 
Table 6.19 Reduction of the environmental impact through optimal water 
exchange network  
156 
Table 6.20 Cost details of the existing conventional water network  158 
 xii 
Table 6.21 LCCA summary for the existing conventional water network  159 
Table 6.22 Cost details of the optimal water exchange network  160 
Table 6.23 LCCA summary for the optimal water exchange network  162 
Table 6.24 Comparison of cost savings of existing and proposed water 
networks  
163 
Table 6.25 Calculation of real rates adopting r7% of change in Production 
Price Index (PPI) 
164 
Table 6.26 Results summary of sensitivity analysis  165 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 xiii 
LIST OF EQUATIONS 
Equation Description Page 
Eq. 1 Freshwater utilised by water sink 90 
Eq. 2 Wastewater generated by water source 90 
Eq. 3 Treated wastewater from water source to water sink 91 
Eq. 4 Objective function 94 
Eq. 5 Water balance at sink 94 
Eq. 6 Water balance at source 95 
Eq. 7 Quality of treated wastewater 95 
Eq. 8 Quality of freshwater 95 
Eq. 9 Additional constraint ensuring single inlet and outlet streams of 
TWW from one entity to another 
96 
Eq. 10 Freshwater utilised by water sink (modified) 122 
Eq. 11 Wastewater generated by water source (modified) 122 
Eq. 12 Treated wastewater from water source to water sink (modified) 123 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 xiv 
LIST OF ABBREVIATIONS 
Abbreviation Description 
 
ADB Asian Development Bank 
BOD Biological Oxygen Demand 
BOI Board of Investment 
CE Circular Economy 
CE-EIP Circular Economy Eco-Industrial Park 
CEA Central Environmental Authority 
CKD Chronic Kidney Disease 
CLD Casual Loop Diagram 
COD Chemical Oxygen Demand 
CPI Consumer Price Index 
CSR Corporate Social Responsibility 
CWWT Common Wastewater Treatment 
DGM Deputy General Manager 
EIP Eco-Industrial Park 
ENA Ecological Network Analysis 
EPZ Export Processing Zone 
FTZ Free Trade Zone 
FW Freshwater 
GPL General Public License 
GWP Global Water Partnership 
HR Human Resource 
IE Industrial Ecology 
IS Industrial Symbiosis 
IWM Industrial Water Management 
IWRM Integrated Water Resource Management 
LCA Life Cycle Analysis 
LCC Life Cycle Costing 
LCCA Life Cycle Cost Analysis 
LP Linear Programming 
MILP Mixed Integer Linear Programming 
MINLP Mixed Integer Non-Linear Programming 
MRQ Main Research Question 
NASL National Audit Office Sri Lanka 
NISP National Industrial Symbiosis Programme 
NWSDB National Water Supply and Drainage Board 
PEIP Planned Eco-Industrial Park 
PLS Plain Language Statement 
PPI Producer Price Index 
PV Present Value 
RIP Retrofit Industrial Park 
SDGs Sustainable Development Goals 
SLSI Sri Lanka Standards Institute 
SNA Social Network Analysis 
 xv 
SOS Self-Organising Symbiosis 
TAC Technical Advisory Committee 
TDS Total Dissolved Solid 
TOC Total Organic Carbon  
TSS Total Suspended Solid 
TWW Treated Wastewater 
UN United Nations 
USA United State of America 
UWW Untreated Wastewater 
WHO World Health Organisation 
WW Wastewater 
ZLP Zero Liquid Discharge 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 xvi 
LIST OF APPENDICES  
Appendix Description Page 
Appendix 1 Semi-structured interview guideline used for Phase II: interviews 
with industry experts and a sample of transcribed copy 
196 
Appendix 2 Semi-structured interview guideline used for Phase III: case study 
and a sample of transcribed copy 
212 
Appendix 3 Test run results of the model obtained from SageMath software 224 
Appendix 4 Coding developed to solve the optimisation problem and the 
experimental results obtained from SageMath software 
225 
Appendix 5 Proposed design of CWWT alteration  228 
Appendix 6 Life cycle cost analysis for existing conventional water network 231 
Appendix 7 Life cycle cost analysis for proposed optimal water exchange 
network 
237 
Appendix 8 Sensitivity analysis – calculations and results 242