The cost of water as a function of the supply method and source type, for remote areas in the Aegean...

7/23/2019 The cost of water as a function of the supply method and source type, for remote areas in the Aegean Islands.

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Heriot-Watt University

School of Engineering and Physical Sciences

MSc in Energy

Project / Dissertation 2008-2009

Title: The cost of water as a function of the supply method

and source type, for remote areas in the Aegean

Islands.

Author: Mr. Kouzoupis Nikolaos - 071256382

Supervisor: Dr. Emilia Kondili (HWUTEIP)

F L A M EFlexible Learning Advanced Masters in Energy


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F L A M E

MSc in Energy

Declaration of Authorship

I, Mr. Kouzoupis Nikolaos071256382Cohort 3

confirm that the reported entitled

The cost of water as a function of the supply method and source type, for remote areas

in the Aegean Islands

Is part of my assessment for module B49IR

I declare that the report is my own work. I have not copied other material verbatim exceptin explicit quotes, and I have identified the sources of the material clearly.

Nikolaos Kouzoupis

(Signature)

Piraeus, 10/9/2008

(Place and Date)


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Abstract

Water is the most valuable natural resource and its shortage is a serious problem faced by

many areas on the planet. The continuously intensifying scarcity of water resources is a

crucial problem in almost all contemporary societies, while the problem of water resources

management in Greece has been widely discussed in the scientific community. Regardless

of the official data, water imbalance is often met, mainly due to the temporal and spatial

variations of the precipitation, the increased water demand during the summer months and

the difficulty of transporting water due to bad weather (Aegean Islands and Crete) or

mountainous terrain (terrestrial areas). In isolated areas, like the Aegean Islands, the high

cost of water due to the water shortage, the islands geomorphology and the increase in the

population due to tourism during the summer season, has long been an issue that needs

addressing.

In terms of the current situation in the Greek water market, one can note that Greece, as a

member of the EU has clear and well established legal framework, but implementation and

regulation are developing. Various water supply methods have been adopted during the last

years, most of them including infrastructure projects, such as dams, desalination units,

ground reservoirs, or infrastructure improvement project, such as distribution networks

refurbishment. As an emergency solution, increasing water demand has been covered by

transfer via ships in the Greek islands. However, there are very significant economic costs

associated with this method, as well as the belief that it is completely unsustainable and

does not create any infrastructure for the long-term solution.

However, it is rather difficult to evaluate potential alternative water supply methods, mainly

due to the fact that their investment and operational cost depend on a large number of

parameters. The possible availability of cost functions or at least qualitative parametric

analysis of the cost of the most widely applied supply methods would be of valuable

assistance in the decision making for water supply projects.

In the present research work, the water sources type and water supply methods used in the

above mentioned areas will be analytically discussed and the characteristics of each method


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will be described. The parameters included in the cost functions will be identified and

efforts are made for the development of cost functions of each separate method according

to the most significant parameters. The supply methods that will be dealt with include

dams, desalination units with conventional and renewable energy sources, ground

reservoirs and water transportation. For each one of the supply methods, the parameters thataffect their cost will be identified and their specific contribution will be approximated. The

specific geomorphology, climate and topography characteristics of the Aegean Islands that

are being dealt with reflect to different parameters affecting the investment and operational

cost, such as the energy that is used, maintenance, repairs, labor etc.

The expected outcome will be cost functions; or, alternatively, cost values ranges will be

suggested on current experience and case studies. The cost functions will refer to the

investment and the operational cost of these supply methods. It is believed that the outcome

of the work will be of valuable assistance for the evaluation of water resources engineering

and management projects and will provide some useful data for the water costing in the

areas of the Aegean islands.


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Contents

Figures..................................................................................................................................VITables..................................................................................................................................VIIGlossary.............................................................................................................................VIIIAcknowledgements.............................................................................................................IX

CHAPTER 1

INTRODUCTION.................................................................................................................11.1BACKGROUND TO THE RESEARCH..........................................................................11.2RESEARCH PROBLEM AND/OR HYPOTHESIS........................................................51.3JUSTIFICATION OF THE RESEARCH (INCLUDING AIMS)....................................51.4METHODOLOGY............................................................................................................81.5DELIMITATION OF SCOPE........................................................................................101.6OUTLINE OF THE DISSERTATION...........................................................................101.7SUMMARY....................................................................................................................12CHAPTER 2

RESEARCH DEFINITION

2.1 INTRODUCTION...........................................................................................................132.2 THE PRACTICAL PROBLEM......................................................................................132.3 THE THEORETICAL PROBLEM.................................................................................182.4 RESEARCH QUESTIONS AND/OR HYPOTHESIS...................................................242.5 SUMMARY....................................................................................................................25

CHAPTER 3

METHODOLOGY3.1 INTRODUCTION...........................................................................................................263.2 RESEARCH PROCESS PLAN......................................................................................263.3 ETHICAL CONSIDERATIONS ...................................................................................273.4 SUMMARY....................................................................................................................28

CHAPTER 4

ANALYSIS AND RESULTS4.1 INTRODUCTION...........................................................................................................294.2 RESULTS OF ANALYSIS: THE FINDINGS...............................................................294.2.1 DESCRIPTION OF THE WATER SUPPLY SOURCES...........................................294.2.2 DAMS..........................................................................................................................444.2.3 GROUND WATER RESERVOIRS / CONSERVATION STORAGERESERVOIRS......................................................................................................................51

4.2.4 OPERATIONAL COST OF DAMS AND GROUND WATERRESERVOIRS......................................................................................................................604.2.5 RESERVE OSMOSIS DESALINATION PLANTS...................................................624.2.6 WATER TRANSPORTATION...................................................................................664.3 SUMMARY....................................................................................................................70


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CHAPTER 5

DISCUSSION

5.1 INTRODUCTION...........................................................................................................715.2 INTERNAL DISCUSSION OF RESULTS....................................................................715.3 EXTERNAL DISCUSSION OF RESULTS...................................................................795.4 SUMMARY....................................................................................................................83

CHAPTER 6

CONCLUSIONS6.1 INTRODUCTION...........................................................................................................846.2 CONCLUSIONS ABOUT THE RESEARCH PROBLEM...........................................846.3 SUMMARY....................................................................................................................86

REFERENCES....................................................................................................................87


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Figures

Figure 1.1: Water demand and availability in Aegean Islands..............................................2

Figure 2.1: Water regions of Greece....................................................................................19

Figure 2.2: Available water resource and water uses per water region in Greece...............20

Figure 2.3: Cost comparison of water supply in the Cyclades Islands................................22

Figure 3.1: The research process plan..................................................................................38

Figure 4.1: Dams classification............................................................................................30

Figure 4.2: Membrane types of dams...................................................................................31

Figure 4.3: The operating principle of normal osmosis.......................................................39

Figure 4.4: The operating principle of reserve osmosis.......................................................40

Figure 4.5: Schematic draft of reserve osmosis desalination system...................................41

Figure 4.6: PVRO system to desalinate sweater without batteries..................................42

Figure 4.7: Unit costs vs. dams capacity in Aegean Islands...............................................46

Figure 4.8: Distribution of the investment cost of dams......................................................58

Figure 4.9: Unit costs vs. ground water reservoirs capacity in Aegean Islands.................56

Figure 4.10: Distribution of the investment cost of Agios Georgios ground water

reservoir.................................................................................................................................59

Figure 4.11: Distribution of the operational cost of dams and ground water reservoir.......61

Figure 4.12: Total production cost distribution of desalination unit....................................63

Figure 4.13: Total production Cost of reserve osmosis desalination unit............................64

Figure 4.14: Investment cost of reserve osmosis desalination unit......................................65

Figure 4.15: Operational cost of reserve osmosis desalination unit....................................65

Figure 4.16: Total cost distribution of water importation from mainland...........................68

Figure 4.17: Cyclades water transport seasonality in 2004.................................................70

Figure 5.1: Cross-comparison of water cost from dams versus ground water reservoirs....77

Figure 5.2: Unit costs versus total installed capacity by the reserve osmosis process........81


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Tables

Table 4.1: Installed desalination units in Cyclades and Dodecanese...................................38

Table 4.2: Water cost from dams.........................................................................................44

Table 4.3: Investment cost parameterization of Aposselemis dam, CreteHeraklion.......49Table 4.4: Investment cost parameterization of Gadouras dam, Rhodes.............................50

Table 4.5: Water cost from ground water reservoirs............................................................52

Table 4.6: Investment cost parameterization of Agios Georgios ground water reservoir,

Crete-Lassithi........................................................................................................................58

Table 4.7: Water treatment plant cost and energy requirements per cubic meter of a dam

based upon the volumetric capacity of the installation for Aegean Islands..........................62

Table 4.8: Water cost and energy requirements from reserve osmosis desalination plant

based upon the volumetric capacity of the installation, for Aegean Island...........................66

Table 4.9: Water transported to arid Islands for the year 2004............................................67

Table 4.10: Water transportation cost and energy required, according to the volumetric

capacity of transferred water, for Aegean Islands.................................................................69

Table 4.11: Seasonality of water transport to Cyclades for the year 2004...........................69

Table 5.1: Evaluation of alternative water supply methods.................................................72

Table 5.2: Selection criteria of water supply methods.........................................................73

Table 5.3: The factors affecting the cost of water from dams in terms of investment and

operational cost.....................................................................................................................74

Table 5.4: The factors affecting the cost of water from ground water reservoirs in terms of

investment and operational cost............................................................................................74

Table 5.5: The factors affecting the cost of water from desalination plants with

conventional and renewable energy sources in terms of investment and operational cost...75

Table 5.6:Investment cost comparison. Desalination plants versus water transportation...78Table 5.7:Production cost comparison. Desalination plants versus water transportation...79Table 5.8: Cost of seawater desalination according to the size of plant..............................82


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Glossary

C Degree Celsius

CO2 Carbon Dioxide; the main Greenhouse gas

kg kilogramkWh kilowatt-hour (1 kWh = 3,600 kJ = 3.6 MJ)

m3 cubic meter

m3/d Volumetric Capacity (cubic meter per day)

PV Photovoltaic system

RES Renewable Energy Sources

RO Reserve Osmosis desalination system

TDS Total Dissolved Solids

WTP Water Treatment Plant

WTW Water Treatment Works


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Acknowledgements

I would like to thank my supervisor Dr. Emilia Kondili for her continuous support and

excellent advice throughout the research; Dr. Phil Skittides and Mr. Alastair Fisher for

editing and proofreading the text. I would also like to express my gratitude and appreciationto Mr. Antonios Kotsonis who gave me significant guidance and access to techno-

economical official documents and studies from the Hellenic Ministry for the Environment,

Physical Planning and Public Works.


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CHAPTER 1 INTODUCTION

1.1BACKGROUND TO THE RESEARCH

Water is the most valuable natural resource and its shortage is a serious problem faced bymany areas on the planet. Water supply chain management and optimisation are evolving as

the most difficult and urgent problems in this field (Voivontas et al, 2003). Mediterranean

countries invested heavily in irrigation schemes in order to confront the water shortage

problem, although the water quality in many countries is likewise a major issue that even

directly induces the improvement of food safety (Chohin-Kuper et al., 2003). In many

Greek areas and, particularly in the Aegean islands, the water shortage problem is acute due

to their geomorphology, low precipitation and seasonal population increase. In recent years,

the water supply problems have significantly deteriorated due to the following parameters

that the islands of the Aegean confront.

1.) The existence of a consequential xerothermic period which has as a characteristicthe low precipitation rate. This effect is the low performance (qualitative and

quantitative) of the existing drills, the non draw down of the existent conservation

storage reservoirs, etc.

2.) High water demand, namely from a rural livestock farming economy to a serviceprovision economy (hotels, lodgements, restaurants, bars, etc.).

3.) Seasonal increase in tourist population particularly during the summer season.4.) The annulment of the traditional reservoirs for the collection and storage of rain

water at each household; this kind of reservoir was capable of covering all domestic

needs.

5.) The loss of the transferred water in the supply networks due to the age of thenetworks. By certain estimations, the percentage of these losses exceeds 30% of the

transferred water (Avagianos, 2001).

The quantitative difference between the water demand and the corresponding availability

on the Cyclades Island group are represented in Figure 1.1, illustrating the magnitude of the

size of the problem.


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Figure 1.1: Water demand and availability in Aegean Islands. (Source: Kondili &

Kaldellis, 2006)

The well known solutions for the confrontation of the water shortage problem and,

therefore, the various supply methods that are used worldwide and described in any

textbook of hydrogeology science, are listed below:

1. Water Drills,2. Dams,3. Off-river lake reservoirs,4. Interception dams to collect water,5. Desalination, and6. Water transportation.

In Greece the first dam was built on the coastline of western Aitoloakarnania, in ancientAlyzia. The dam is dated to the 1st B.C. century and it has been maintained as a visiting

monument until today. Nowadays, there are up in excess of 150 big and 150 small dams

constructed in Greece (Bournatzi, 2008). The main aims for the construction of a water

reservoir plant are relatively close to those for the installation of a dam. Generally,

geophysical, climatic, hydrologic, socio-economic, water use and facilities prospecting data


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methods are commonly used from scientists to determine the final selection (Georgakakos,

2007). Dams are usually built in areas, which are close to the upper and middle part of

rivers (Savvaidis, et al. 1999).

The idea of water reservoir development in Greece is not recent, but represents an old andtraditional way for the storage of water in winter and its consumption in summer.

Generally, it is known that in several regions of our country and mainly in the Aegean

Islands, small water cisterns (for pluvial water collection) have been installed in order to

cover individual needs. On the contrary, the water reservoir plants are highly varied and for

collective usage. For example, in a small village of Chios Island, a big water reservoir plant

was constructed forty years ago by local grangers, in order to cover their needs for

irrigation. Also, in Pantanassa village of Lakonia region, an installation with a similar

capacity of ten thousand cubic meters was constructed in 1975 (Efthimiou &

Theodoropoulos, 1997).

Desalination also goes back to ancient times when Greek sailors used evaporation to purify

seawater (Alishiri, 2008). In the last decade desalination has been considered as a solution

for potable water needs only for specific water scarcity countries which have cheap fuel at

their disposal. Nowadays, desalination is used extensively even in Greece, due to the

reduction in desalination cost, and the high cost of dams and water transfer to Greek

Islands. Therefore, considering the alternatives, desalination can significantly cover or

assist the water needs of a small Island. Also, the reduction in the cost of desalination units

is due to new developments and improvements in current technologies, particularly in

Reserve Osmosis (RO) technology (Reddy & Ghaffour, 2007).

For a long time, increasing water demand was covered by transfer via ships between the

Greek islands. However, there are very significant economic costs associated with this

method, as well as the belief that it is completely unsustainable and does not create any

infrastructure for a long-term solution (Kondili & Kaldellis, 2006).

The supply augmentation options that have been implemented in mainland Greece are

suitable for the small Islands of the Aegean Sea and are as follows (Manoli, et al., 2003):

1.) Desalination, and desalination using Renewable Energy Sources,


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2.) Mobile floating desalination,3.) Construction of dams and surface storage reservoirs,4.) Exploitation of groundwater resources through boreholes,5.) Water transfer (via vessels), and6.)

Waste water reclamation and reuse.

Water supply methods burden local authorities with a specific cost, and in proportion to the

total annual cost of each process, one can accomplish a decision making process related to

the components of the operational cost and, definitely, to the cost of the initial investment.

More specifically, in our case the cost depends on local conditions and the seasonality of

demand. The interdependencies in the Integrated Water Resources Management (IWRM)

concerns a link between water resources, water used and water services, creating a chain

(Manoli, et al., 2003). The specific geomorphology, climate and topography characteristics

of the Aegean Islands that are being dealt with, engender different parameters affecting the

operational cost, such as the energy that is used, maintenance, repairs, labor etc. However,

the water cost evaluation procedure that is widely used, suggests alternatives for the supply

augmentation (Manoli, et al., 2003):

1.) Economic Evaluation for water costing:a. Production cost

i. Capital Costii. Operational and Maintenance Costs

b. Lifetime Analysisc. Financing Mechanisms

2.) Technical Considerations:a. Equipment reliabilityb. Experiencec. Dependence on climate conditionsd. Flexibilitye. Construction Period, andf. Quality issues

3.) Environmental/Social issues, namely main impacts on:a. Ecosystems


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b. Aquifersc. Air quality

Thus, with a multi-criteria analysis one is led to the optimum solution(s) for each specific

area.

1.2RESEARCH PROBLEM AND/OR HYPOTHESIS

The problem of limited water resources, in Greece and elsewhere, has been widely

discussed in the scientific community. In isolated areas, like the Aegean Islands of Greece,

the high cost of water due to water shortage, the islands geomorphology and the increase

in the population due to tourism during the summer season, has long been an issue that

needed addressing. The research problem of this investigation is to derive and discuss

analytically the different types of water sources and water supply methods used in the

above mentioned areas. Additionally, the characteristics of each method will be expressed

as a function of cost. The outcome of this investigation will be a valuable tool for

supporting the decision making process for water supply investment for infrastructure

development.

1.3 JUSTIFICATION OF THE RESEARCH (INCLUDING AIMS)

Regional development and the preserve of natural balance are the essential issues that

concern the sourcing of water, in the current environmental climate. Although it is a

renewable resource, peoples overuse engenders great pressure and strain on water supply

in current situations. In addition to this, water quality is a complex issue, involving

diminished water availability and the scarcity of resources in general, in remote areas

(Avagianos, 2001). Traditionally, water has been a very valuable resource in the Aegean

Sea region, as one of most precious natural resources and indispensable for human beings

and economic growth(Ranhang & Shouyu, 2008). Hence, the water resources in most of

the islands are not sufficient to cover the continuously increasing needs (Kaldellis &

Kondili, 2007). The degradation of water quality in Aegean Islands, as a result of the


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diminished water availability and therefore its cost, has some specific local features

(Avagianos, 2001):

a.) The irrational water resource management.

b.) The interpenetration of the sea in underground levels due to over-pumping.

c.) Small built-up areas and the seasonal increase in population during the summerseason, encumber the production and the distribution of soil.

d.) Uncontrollable waste disposal sites construction and soil distribution.

e.) Interspersed agricultural and fodder plants of small potential.

f.) Restricted industrial plants

g.) Contention for the ensuring of the necessary water quantities.

Those specific characteristics demonstrate that it is worthwhile developing a method for

water cost determination in real cases. Therefore, we can agree that demand and supply

must be kept in a balance; otherwise the water resources for the next generation are

seriously endangered(Kaldellis & Kondili, 2007).

From all the above universally acceptable aspects, we can note that the present research

will deal with beneficial issues, trying to implement a tool with advantages that concern the

proper water costing and, consequently, proper water pricing. The proper water cost (i.e.

how efficient the process of pumping and preparing the water for use) results in rational

pricing, and is a tool for the ideal conservation of water.

Many approximate projects have dealt with the identification of the parameters affecting

the cost of water in the Aegean Islands. Specifically, Manoli E., et al. dealt with the

parameters affecting the cost of water supply in small Aegean Sea Islands (Manoli, et al.,

2003). Also, water supply methods and the source type that is used in the specific area are

practically noted by previous works. For example, Chohin-Kuper, A et al. reforms water

policies about pricing of water, cost recovery, water demand and impact on agriculture for

the improvement of the Mediterranean Sea (Chohin-Kuper et al., 2003).

In addition, other similar models have been developed, such as Ranhang, Z. & Shouyu, C.

construction and application model, but for urban water resources. (Ranhang & Shouyu,

2008). Therefore, the main processes of our research have already been engaged by the

Greek or worldwide scientific community. Furthermore, the fact there has not been a


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parallel research to the urban water resource models, into models for water resources on

small islands such as the ones of the Aegean, proves the practical validity of this research.

One can evaluate that the main benefits from this research are the accomplishment of a

more accurate future prediction of the water cost for every newly project plant, i.e.desalination plants, dams, ground reservoirs, wells, ship transport approach, etc. Also, the

evaluation of the existing water supply sources will be a beneficial outcome of the research.

The research will interpret each supply methods characteristics as a function of the water

cost, defining the water supply methods and source types as well. Considering the existing

situation in the Aegean Islands, a more rational management of all water resources due to

economical optimization is definitely required. However, we can suggest that there are

good prospects that the outcome of the research will be significant for future projects and

therefore, as a result of undertaking this work, there will be only beneficial consequences.

Water supply problems are in many cases confronted by way of the development of new

infrastructure projects. Furthermore, there may be more than one alternative type of project

that could be constructed. In any case, the final decision includes not only technical but also

economic aspects and the cost of the resulting investment should be evaluated on a long

time-horizon basis.

Therefore, the main aim of this project is to create a method for calculating the cost of the

water from each separate water supply method that will aid the process of the optimal

selection of the most suitable water supply project and also the operational cost of the

water. To that effect the parameters that affect water cost and the resulting cost functions

will be determined and validated in specific cases studies. As a result of the process, a

valuable tool to support the decision making process for a water supply investment in the

Aegean Islands will be developed. The sub-objectives (main steps) to achieve this aim

were:

To specify the types of the problem that will be approached, i.e. in which cases wewill develop water costing methods, i.e. specify the limits and the extent of the

work.


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To work out the selection of the problems that will be examined, i.e. for which typesof water supply usage combinations we will develop costing tools for.

To identify the parameters of the problem in each case. To identify the parameters affecting the cost of water. To determine the proper costing method and model for each specific case in order to

implement case studies.

The final step is to validate the results of the project.

In order to accomplish the main aim/objective, or during the above procedure, one should

also investigate the present state of the water supplies that are used in the Aegean Islands,

and to determine the cost of each water supply method using official data. Likewise, one is

able to study and to analyze if there are available technologies which lead to lower water

costs than the cost of the current systems that are being used in the corresponding area.

1.4METHODOLOGY

Describing the present research, one can say that its primary aim is to solve a particular

problem; Engestrm (1999) is concerned with discovering, interpreting, and the

development of methods and systems for the advancement of human knowledge on a wide

variety of scientific matters of our world and the universe, therefore, it can be

characterized as applied research. The research process planning procedure comprises four

main steps that constitute the methodology of the research (Skittides & Koiliari, 2006) as

follows.

The first step constitutes the research approach method selection that, definitely,

presupposes the proposed title selection. The present research is an empirical research,

namely it is based on the implementation of results. Next, the inductive approach has beenadopted, because the data that we are able to collect, infer a general theory. This type of

empirical research according to Stanbrough (2005) is defined as: The method that starts

with many observations of nature, with the goal of finding a few, powerful statements about

how nature works (laws and theories). The concept behind this research is based on a

researchable relationship between multiple variables, or similarly, multiple parameters in


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our case. The parameters concern the specific localized characteristics that directly or

indirectly affect water cost. Therefore, water cost reduction, the central, even pivotal point

of the research, is investigated in order to be predictable. However, the empirical research

approach is connected with a co-relational research in which, according to Cohen and

Manion (1994), a relationship among phenomena is investigated with a view to predicttheir association.

Secondly, the type of the design that the present research is going to utilize is a survey and

case study combination. Initially, we will carry out a survey about the water supply

methods that are used in the specific area, namely the water transfer, desalination,

desalination with RES, dams and wastewater reuse, presenting the specific costs of each

supply method. Accordingly, we will use these costs in order to implement a valuable tool

to define the actual variation of the water cost according to some parameters of the specific

localized characteristics. These parameters should already be defined. Thus, the research

object will consider a present or past situation, positing a forecasting extension of the

future, in the context of a diachronic-evolutionary research (Skittides & Koiliari, 2006).

The third element of the research methodology that should be covered is the proposed

category of activity. The category of cross-sectional study is also applicable since,

according to Skittides and Koiliari (2006), we are going to investigate differences in a set of

phenomena at only one time in a small number of settings, and not over time, as the

longitudinal category relates. Particularly, the present research, as above mentioned, will

provide an answer to the research problem of reducing the cost of water in the Aegean

Islands at the present time, investigating the corresponding water supply method and source

type, and, therefore it can be described as a cross-sectional case study.

The final step constitutes the data gathering technique/techniques. There are multiple

techniques that the researcher has to implement in order to gather the available and correct

data. In the present case, we should follow a multiple data gathering selection. The

companies and publics files analysis, and also the use of secondary material are the

investigative techniques that we are able to apply in order to gather the desirable data.

Besides what we have said above, nevertheless, the proposed title of the present research


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claims that it is a qualitative research. As Denzin and Lincoln (2005) state that qualitative

research isa situated activity that locates the observer in the world, namely it involves

an interpretive and naturalistic approach to the world. Also, as Lazaraton (2003) notes, the

qualitative research consists ofa set of interpretive material practices that make the world

visible. The aim of the qualitative research is to attempt to make sense of, or interpret,phenomena in terms of the meaning people bring to them (Hoepfl, 1997), and more

specifically, it may involve the studied use and collection of a variety of empirical

materials, such as a case study, personal experience, introspection, life story, interview,

artifacts, cultural texts and productions, observational, historical, interactional and visual

texts (Denzin and Lincoln, 2005). Accordingly, qualitative researchers deploy a wide range

of interconnected interpretive practices, hoping always to get a better understanding of the

subject matter at hand. Hence, there is frequently a commitment to using more than one

interpretive practice in a study (Miles & Huberman, 1994).

1.5 DELIMITATION OF SCOPE

In the present research work, the type of water sources and supply methods used in the

above mentioned areas will be analytically discussed and the characteristics of each method

will be described. The parameters included in the cost functions will be identified and

efforts will be made for the development of cost functions of each separate method

according to the most significant parameters. The results of the work will be validated with

integrated case studies for representative Aegean islands to compare the water cost for

various alternative water supply methods. Indicatively, islands of average and small size

that could support different water supply methods will be taken as the basis for the

validation of cost functions.

1.6 OUTLINE OF THE DISSERTATION

The first chapter is an introduction to the present study. The definition of the research

problem, the aims, and the justification of the research allows the reader to clearly

delimitate the scope of the present work; in addition to the strategic and tactical choices

which are explained via the methodology presented in this chapter.


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The second chapter is the main research definition, namely an analysis of the practical and

theoretical problems. The defined practical problem describes any possibilities of

minimising water cost, and presents a water cost evaluation method. In the context of the

theoretical problem the available water resource and water uses per water region in Greeceis described, while a cost comparison of the current water supply in the Cyclades Islands is

listed as a representative sample. Also, the fundamental description of dams, ground water

reservoirs, desalination, and water importation in the case of Aegean Islands in terms of the

costs is presented in order to accumulate representative data of each supply source situation

in the specific place. The research questions, which will give guidance towards the

practical and theoretical problem clarification, are also listed. Also, in the second chapter

the basic characteristics of all available supply sources, namely, dams, ground water

reservoirs (conservation storage reservoirs), desalination plants, and, water import are

analytically discussed in terms of the conditions on Aegean Islands.

The third chapter contains the research process plan. Furthermore, it consists of certain

steps that will be followed during the analysis of the core problem. Also, the ethical

considerations of the present research are discussed.

The fourth chapter contains an elaboration of the collected data and the results. An analysis

of all water supply sources is carried out with respect to the water cost per cubic meter, and

both investment and operational cost of each supply source.

The fifth chapter discusses and analyzes the results. Internal discussion of the results that

are presented in the previous chapter is a cross-comparison between the cost of water from

dams and ground water reservoirs, and, also, between the cost of water between

desalination and water importation. As regards the external discussion, alternative

theoretically researched methods for the determination of the water cost from dams or

ground water reservoirs are presented. Finally, the implications of the uncertainties in data

are discussed.


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The final chapter presents the conclusions of the research work. The conclusions are

derived from the analysis carried out in chapter 4 and the discussion in chapter 5 and are in

essence the answer to the research problem and research questions by means of cross

reference to all the findings.

1.7 SUMMARY

This chapter introduces the current situation and characteristics of the Aegean Islands.

More specifically, solutions for facing the water demand in combination with the problems

concerning the water shortage and the particular geomorphology of the specific area are

presented and utilized. Based on the above justification, the research problem is defined as

how we can reduce the cost of water as a function of the supply method and source type in

those remote areas. The methodology that will be adopted for finding the appropriate

solution to define the cost of water and then to minimise its cost are also described. Finally,

the outline of the dissertation is presented.


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CHAPTER 2 RESEARCH DEFINITION

2.1 INTRODUCTION

The research definition concerns the practical and theoretical problems. The followingparagraphs try to address the practical problem, namely the reason we are looking for the

most economically efficient water source and what needs to be done to define those

parameters that affect the cost. Likewise, the theoretical problem concerns the

environmental water management in Aegean Islands. Finally, the research questions that

will drive the research towards finding an answer to the research problem are presented.

2.2 THE PRACTICAL PROBLEM

The problem environment:The demand for exploiting any contingent water resource as a

more economically useful solution than the existent situation; introducing the parameters

affecting the cost in the Aegean Islands.

The problem of water shortage in Greece is significantly acute, and particularly in the

Aegean Islands, where the water resources are quite limited and the water reserves are not

adequate to cover the needs of the population; additionally, the problem deteriorates during

the summer months, when the demand increase by a factor of about four or five times at

that of the winter level, due to national and international tourism data (Karagiannis &

Soldatos, 2007). Water resources must be developed, exploited and used in a sustainable,

economically efficient, integrated and multi-purpose manner. Water in production should

be considered as economically efficient and a subsidized system should be established.

Activities in water resources protection and development and in water service provision

should be performed with the participation of all social and economic sectors (MNRE,2008). Regarding the water cost, the main problem of non conventional resources is that

surface and underground water are undervalued or usually subsidized. Given that the non

conventional resources appear valued with a real or almost real cost, it is necessary to apply

some incentives to encourage the use of these resources (Hernndez, 2006).


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The area under consideration, i.e. Islands of South and Central Aegean Sea, is a semi-arid

region (aridity index: 0.30) with precipitation: 380mm/yr (European Communities, 2003).

Therefore, the Islands of the Central and South Aegean Sea are characterized as the most

arid regions of Greece (Kaldellis, et al., 2004); the aggravating factors of limited run-off

potential, and the overexploitation of groundwater resources during summer is the result ofthe seasonal population increase (Manoli, et al., 2003). In many small Aegean islands the

water shortage problem is solved through the transportation of potable water, whereas in

the larger islands a significant number of water surface reservoirs and dams are constructed,

for the collection of rain water. The yearly amount of transferred water is 2,500,000 m 3

(Kaldellis, et al., 2000). Recently, significant interest has been exhibited in the construction

of water tanks for the storage of energy in the form of water inventories during the low

demand periods, and their exploitation during peak demand periods. The suitability of each

one of the alternative water management solutions depends on the specific characteristics of

the island, while each solution implies a different cost. (Kaldellis, et al., 2004). Inclusive of

the above, prudent water resource exploitation is absolutely necessary. The

interdependencies of the Integrated Water Resources Management (IWRM) that concerns a

link between water resources, water uses and water services, creating a chain (Manoli, et

al., 2003) can become the guidance in order to gather information concerning

corresponding environmental problems. With the implementation of an Integrated

Management, one can contrast the current situation of water resources, with the predictable

effects in order to decide the cost effectiveness of an investment and all environmental and

other impacts.

The problem context:Water cost abatement in remote areas of Aegean Islands.

Water cost reduction is an issue that motivates scientists worldwide because it is related to

water destruction. Most certainly, water cost reduction is related to an important benchmark

of pricing policies. The contribution of those policies toward economic efficiency is a

complex issue but nonetheless remarkable. An efficient policy may be defined as one which

maximizes the net benefits accruing to a community from a given course of action, with no

consideration paid to the way in which those benefits are distributed. The objective of


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pricing policy could be one or combination of the following (Abu Qdais & Al Nassaym,

2001):

1. To allocate resources efficiently between sectors within the economy and within thesector itself.

2.

To satisfy the consideration of equity or the ability to subsidize consumers,especially the poor.

3. To raise revenues to meet financial requirements for providing the service.4. To subsidize special areas to encourage development.5. To take into account political consideration for a special area or subsector of the

population.

For most countries satisfying these multiple objectives would involve a trade-off.

The context of the problem of the present work is to examine the relationship between the

price and the cost of water. Considering that in our case the price is dependent on water

cost, it is necessary to present some useful relationships. Many researchers have

investigated the relationship between the price of water and the consumption level (Abu

Qdais & Al Nassaym, 2001).

Babbitt, Donald and Cleasby (1962) have indicated the following relationship (Abu Qdais

& Al Nassaym, 2001):

C = 21logQ

Where,

C =Cost, dollars/1000 ft3 ;

Q =rate of water used in thousands of gallons per year.

Walski, Richards, McCall, Deb, and Morgan (1985) developed a model for evaluating the

effectiveness of water conservation measures. Among the conservation measures evaluated

was the price of water. A reduction factor in water use was calculated as a function of water

price elasticity as follows (Abu Qdais & Al Nassaym, 2001):

R = 1.0(P1/P2)e

Where,

R = reduction factor;


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P1 = initial price;

P2 = final price;

e = elasticity of demand, which is a measure of how strongly the quantity demanded

responds to change in price.

Although Walski et al.(1985) do not give the potential reduction factor that may be

achieved by increasing the water price, they indicated that the price has a higher coverage

value than other conservation measures such as water conservation devices and public

education, which means, that the number of consumers that will react to a change in price is

higher than those who will react to other measures (Abu Qdais & Al Nassaym, 2001).

Twort, Law, Crowley, and Ratnyak (1994) suggested the following formula (Abu Qdais &

Al Nassaym, 2001):

Q = Kpe

Where,

Q = is the demand at price P per unit of consumption;

P = price per unit of consumption;

K = constant;

e = elasticity of demand.

The water demand elasticity (e) can be calculated as follows:

e =Percent change in quantity/Percent change in price

Finally, it should be noted that in several cases of increasing the price of water, in many

places in the world, there has been a fall in consumption (Abu Qdais & Al Nassaym, 2001).

The problem of interest:What needs to be done to define the parameters affecting the cost

of water according to the water supply method and source type.

In order to define the parameters affecting the cost of water we are able to follow a water

cost evaluation method. The water cost evaluation procedure that Manoli, et al. use,

suggests alternatives for the supply augmentation (Manoli, et al., 2003):


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1.) Economic Evaluation:a. Production cost

i. Capital Costii. Operational and Maintenance Costs

b.

Lifetime Analysisc. Financing Mechanisms

2.) Technical Considerations:a. Reliabilityb. Experiencec. Dependence on climate conditionsd. Flexibilitye. Construction Period, andf. Quality issues

3.) Environmental/Social issues, namely main impacts on:a. Ecosystemsb. Aquifersc. Air quality

Thus, with a multi-criteria analysis one is led to the optimum solution(s) for each specific

area.

Also, a more tangible and detailed model is suggested by Hernndez (2006). The objective

of this model is to minimize the total cost necessary to obtain water resources from

different sources to satisfy water demand in a region. This optimization model focuses on

the comparison of the different cost structures associated with the various alternative water

supplies. In this model are included data from the following resources that should be

defined:

1. Conventional resources (surface water and underground water), and2. Non-conventional resources (reclaimed water, desalinated water and transferred

water).

Finally, these sources can be ranked in terms of their price in different scenarios. If some

quantities of water supply are calculated, the model will provide through mathematical

programming the optimal price for each water supply type to apply to each of the uses or


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contemplated demands. Likewise, if the water prices are obtained using the principle of

Full Cost Recovery, the model could provide the optimal quantities of water to obtain from

each one of the considered sources and the optimal quantities to allocate to the different

destinations (Hernndez, 2006).

2.3 THE THEORETICAL PROBLEM

The subject:Environmental water management.

The continuously intensifying scarcity of water resources is a crucial problem in almost all

contemporary societies (Bithas & Stoforos, 2006).This issue currently affects many regionsof the world. Without a significant reversal of economic and social trends, it will become

more acute over time (European Communities, 2005). Water resources must be viewed

holistically to ensure their sustainability, both in their natural state and in balancing competing demands on them - domestic, agricultural, industrial (including energy), and

environmental. Sustainable management of water resources requires systemic, integrated decision-making that recognizes the interdependence of three areas; namely decisions on:land use, our economic and social future, and at the international, national, and local levels

(Burton, 2003).

According to water resources legislation (1739/87 for the management of water resources),

Greece has been divided into fourteen water regions as follows: West Peloponnese, North

Peloponnese, East Peloponnese, West Central Greece, Epirus, Attiki, Central Greece and

Evia, Thessaly, West Macedonia, Central Macedonia, East Macedonia, Thrace, Crete and

Aegean Islands (Ministry of Development, 1987). The fourteen water regions of Greece are

illustrated geographically in Figure 2.1.


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Figure 2.1: Water regions of Greece (Source: European Communities, 2003)

The fact that a precise estimation of the available water resources in Greece has not been

made yet is noteworthy. The only available information about this issue is that most

authorities agree that the water consumption and use constitute less than ten per cent of the

annual precipitation and fifteen per cent of the water potential. Also, it is estimated that the

water consumption in Greece increases by more than 3% per year. The major water uses in

Greece, as we can see in Figure 2.2 below, are mainly irrigation use and secondly domestic

use.


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Figure 2.2: Available water resource and water uses per water region in Greece (Source:

European Communities, 2003).

Regardless of the official data, water imbalance is often met, mainly due to the temporal

and spatial variations of the precipitation, the increased water demand during the summer

months and the difficulty of transporting water due to bad weather (Aegean Islands and

Crete) or mountainous terrain (terrestrial areas) (European Communities, 2003).

In terms of the current situation in the Greek water market, one can note that Greece, as a

member of the EU has a clear and well established legal framework, but implementation

and regulation are still developing. The fact that there is no single, over-arching pricing and

service regulation system in the country is an indicative example of this slow development

and lack of proper implantation of legislation. It is also unlikely that the systems adopted

by individual municipalities work faultlessly.

Kaldelis et al. (2004) classify the arid Aegean Islands into three categories based on their

average summer season daily water deficit as follows:

First category:Average summer fresh water deficit: 1,000-2,500 m/d.

These islands are: Koufonisia, Kimolos, Tinos, Milos, Lipsi, Megisti, Nisiros, Patmos, Simi

and Halki.

Second category:Average summer fresh water deficit: 100-250 m/d.


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These Islands are: Amorgos, Heraklia, Schinousa, Folegandros, Sikinos, Thirasia and

Agathonisi.

Third category:Average summer fresh water deficit: 10-25 m/d.

These Islands are: Donousa, Palionisos (North Kalimnos) and Pserimos.

The Area:The cost of water from all available water resources / infrastructures.

Typically, water use is categorized by its three major uses: agriculture, industry, and

domestic consumption often measured as municipal use. In global terms agriculture is seen

as the sector that uses the most water. However, in countries with a higher per-capitaincome, industry accounts for a higher share of water withdrawal according to World Bankestimates (European Communities, 2005).

In Figure 2.1, we observed the allocation of the water regions of Greece, but even in areas

where supplies of water are adequate, the problem of scarcity is usually confronted through

the deterioration of water quality. Generally, the actual production cost of water in an

acceptable quality includes the operational cost (staff wages, cost of energy, expendable

materials, etc.), and the fixed accoutrements depreciation. The more reliable cost

production data are collected by the Ministry of Aegean Sea which is normally acquainted

with both the investment costs for new installations, and the cost for the water transport

(Kaldellis, et al., 2004). Therefore, the increase in the costs for certain water uses, and

mainly for the indoor use is the result of the decrease in water quality (Bithas & Stoforos,

2006). Before the presentation of the costs analysis according to the corresponding water

supply method, it is useful to assign some values which are the foundation of the estimated

costs. These values concern the individuals desire and acceptability, and more specifically:

the willingness to pay for a commodity, and the willingness to accept individuals to acquire

a resource (Markandya, 2003). The willingness to pay and willingness to accept are

determined empirically and range proportionally by country, region or city. The willingness

to pay and willingness to accept concepts are fundamentals in order to analyze the basic

tools used in any cost analysis, and also to identify how these costs are relevant to the

pricing of water (Markandya, 2003).


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The Aegean Islands cover an area of 9,103 km2. Also, the Cyclades Islands are a complex

in the Aegean Sea that comprises of 39 Islands (24 inhabited) and cover an area of 2,432

km2. Costs data from previous works can be a representative sample in order to account for

the condition of the present situation of water resources management in the Aegean Islands.

Figure 2.3: Cost comparison of water supply in the Cyclades Islands (Source: Manoli, et

al., 2003)

All desalination plants are considered to have grown rapidly in the Aegean Islands,

developing a cost effective solution for water supply. However, water transfer via vessels is

still a widely used old method in areas of the Aegean Islands where no initiatives or

appropriations have been taken. Unfortunately, the supply methods like water transfer,

where the cost depends on local condition, are obsolete and in need of modern techniques

in order to minimize the overall cost and to maximize the profits of the investments

concerning water management in remote areas.

The gap in knowledge: The lack of knowledge concerning the implications of using

obsolescent water supply methods for remote areas in the Aegean Islands.

After the available data analysis, the results show that the North Aegean Islands have

relatively sufficient water resources for the coverage of potable water needs, while there is


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the reasonable possibility of a water shortage for irrigation needs in the near future. On the

contrary, in the complex of Cyclades Islands the water shortage problem is fairly acute.

Regardless of the official data processing, ground water reservoirs and desalination plants

have been constructed in some Islands (Ios, Mykonos). It is also scientifically proven that

there are some Islands among the Cyclades, in which the available water resources are notutilized or are underutilized, however, there are other Islands such as Andros and Naxos,

which dispose adequate water resources that are efficiently exploited (Kaldellis, et al.,

2000).

The gap of knowledge which can be identified is that there is not a standard water cost

production allocation system in order to calculate the documentary operational cost of a

corresponding installation. Additionally, it is widely accepted that the adoptive pricing

policy does not reflect -for social reasons- the actual cost of water, and, therefore, the water

shortage problem is not obvious in the local communities. The result is that the residents do

not fully realize the water shortage problem (Kaldellis, et al., 2004). Correspondingly,

many incorrect opinions and the absence of knowledge of the profits of the investments

concerning the water management in remote areas seem to be the main obstacles for any

technological innovation. As we have already said, whilst new desalination plants have

been installed in some Aegean Islands, there are still remote areas where no initiative has

been taken and water transfer via vessels is the only water supply method. Also, the

appropriate funding for the creation of alternative projects, such as ground reservoirs, dams

and wastewater treatment plants, is not the main priority that has been scheduled. The main

parameters that complicate the development of new desalinating or other alternative

technologies are listed below (Manoli, et al., 2003):

1.) The quality of the supply water.2.) The cost of the investments.3.) The place/ground availability.4.) The energy demand and availability.5.) The experience of the staff required.


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Nevertheless, there are many promising parameters that should be taken into account when

attempting to subsidize the economical development of the Aegean Islands. An

improvement in the infrastructure type of a specific place can boost the development many

times over, such as the upgrade of the quality of life, the increase in tourism and the

creation of new employment. Therefore, one can estimate all parameters affecting the costof an investment and the posterior consequences before the final step, but it is obvious that

all signs are encouraging, especially in the case of the Aegean Islands.

2.4 RESEARCH QUESTIONS AND/OR HYPOTHESIS

Generally, the research questions are absolutely essential to the investigator in order to

determine the basic and specific elements of the research problem. The disaggregation

between practical and theoretical problems can be effectively separated by answering the

appropriate research questions, while refining, with the most prudent methodological steps,

the proper initial research area and the desirable goals. Therefore, the research questions

should be accurately and lucidly defined. They are listed below:

1. What is the current situation concerning water resource management in the AegeanIslands?

2. What are the primary and secondary water uses in the Aegean Islands?3. Which are the current water supply methods that are employed?4. What alternative technologies are used today worldwide for water supply?5. Which of these technologies is/are appropriate to implement in the Aegean Islands?6. What is the relationship between the cost and the price of water in our case?7. Which parameters affect the cost of the water supply method that is used according

to the source type in each case?

8. By how much can we reduce the cost of water and which areas will presentobstacles and difficulties?


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2.5 SUMMARY

In the second chapter the research was defined by means of analysing the practical and

theoretical problems. The defined practical problem describes any possibilities for

minimising water cost, presenting a water cost evaluation method. In the context of thetheoretical problem the available water resource and water uses per water region in Greece

was analytically described by their basic principles, while a cost comparison of the current

water supply in the Cyclades Islands is listed as a representative sample. Finally, the

research questions which will give guidance towards the clarification of the practical and

theoretical problems are also listed.


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CHAPTER 3 METHODOLOGY

3.1 INTRODUCTION

In this chapter the research process plan has been developed. The overall steps of the

project are presented in terms of schematic appearance. The main procedure illustrates how

I will be able to achieve the basic goals that are defined in previous chapter(s). Also, this

third chapter attempts are made to give descriptions in as much detail as possible,

describing all the steps taken and procedures held.

3.2 RESEARCH PROCESS PLAN

The research process plan presents all of the basic steps in order to accomplish the present

research. The primary procedure repeats for each supply source that I have already selected.

The available supply methods that are mainly used in Aegean Islands are: dams, ground

water reservoirs (conservation storage reservoirs), desalination plants, and water transport

via tanker boats (water importation).

The initial process for all supply methods concerns the examination of the total production

cost of each plant. It is necessary to check if there is an operational cost, and if the answer

is yes, I should firstly define the operational cost, and secondly the investment cost. If the

answer to the initial question is no, I should directly determine the investment cost of

each plant. In case of water importation, considering that there is no investment cost, the

term of operational cost concerns the energy requirements. Next, I will parameterize the

investment cost in order to define the parameters affecting the cost of water. For that

reason, I will collect real data from several dams and ground water reservoirs, while a

lengthy literature research will be carried out for desalination plants used in Aegean Islandsand water importation options. Finally, estimation for the size of the project in relation with

the total production cost of water per cubic meter to be comparable will be made for all

available sources. The results will be very useful for the final step of water cost reduction

assessment. Referring to specific Island(s), and using all the above selected data we will

discuss if there is any water cost reduction option for Aegean Islands.


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Figure 3.1: The research process plan. (Source: The author).

3.3 ETHICAL CONSIDERATIONS

The present research is a technical project that uses data collected from literature research,

and is also conducted in an ethical manner by the researcher who has requested permission

by the Hellenic Ministry for the Environment, Physical Planning and Public Works. More

specifically, the access to official documents carried out with authorization from Mr.

Kotsonis Antonios, director of the Ministrys D4 section. The author has been grantedaccess to techno-economical official documents and studies, and is authorized to use and

publish the data gathered, however, for educational research reasons only. The good quality

of literature sources and the reliability of the data prove the trustworthiness of the research.

The progress of the work was always under the supervision of my tutor and hence the

explanation of results remained open to suggestions, so as to avoid any ethical problems.


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The project is considered worthwhile since it produces favorable results for the public at

large. Also, the present research does not receive any funding, neither use laboratory

infrastructure nor other kind of facilities. Therefore, the only ethical issue that one should

take into account is that the presented data can be used only for educational research

reasons only.

3.4 SUMMARY

In the third chapter the research process plan of the research was presented. The research

process plan presents all basic steps in order to accomplish a water reduction assessment for

the specific place of Aegean Islands. Each step was analysed, and, finally, the ethical

considerations for conducting the research were presented.


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CHAPTER 4 ANALYSIS AND RESULTS

4.1 INTRODUCTION

This chapter contains the presentation and elaboration of gathered data. An analysis of allwater supply sources will be carried out in respect to the water cost per cubic meter of each

one. In order to accumulate representative data of each supply source situation for the

Aegean Islands, I will accomplish an examination of investment cost, for the case of dams

and ground reservoirs, and I will parameterize the total production cost of reserve osmosis

desalination plants and water importation. The cost results are presented in tables, graphs

and pie charts where it is necessary.

4.2 RESULTS OF ANALYSIS: THE FINDINGS

4.2.1 DESCRIPTION OF THE WATER SUPPLY SOURCES

The main available methods, which are most commonly used in the Aegean Islands,

ensuring water resources are: dams, ground water reservoirs, desalination units, and water

transfer via tanker boats. Dams and water reservoirs are intended to cover the basic

irrigation and water supply needs as well as to give an integrated solution to the problem of

water management, while desalination constitutes a reliable solution offering good quality

potable water in a cost comparable to or lower than other methods (Tzen, 2001). Following,

there is a fundamental analysis, and the basic principles of the water resources that this

research will take into consideration.

Dams:

A dam is a barrier that can prevent, redirect or decelerate a natural water flow while the

primary purpose of a dam is to retain water in a specific place. Usually, for that reason, in

addition to the dam construction, many other auxiliary devices are installed, such as, water

collectors, reservoirs or even artificial lakes. Dams are classified into various categories

depending on their manufacture, operation and feasibility. According to their operation,


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dams can be distinguished as: elevation level of the dams, storage dams, and channeling

dams. Also, according to the aim for which they are constructed; they are characterized as:

dams for irrigation, water supply, energy production, etc. Dams are classified, by

constructional characteristics, according to the following Figure (Dimitriou, 2006).

Generally, dams are constructed in Greece as river water reservoirs, and they are usually

from reinforced-concrete caisson (R.C.C) or with clay core, or rockfill dams with uphill

plate. For that reason, I will focus this studys interest on rockfill dams. In a 1960

symposium on rockfill dams sponsored by the American Society of Civil Engineers

(ASCE), a rockfill dam was defined as (Breitenbach, 2004c): A dam that relies on rock

either dumped in lifts or compacted in layers, as a major structural element. An

impervious membrane is used as the water barrier and can be placed either within the

embankment (internal membrane) or on the upstream slope (external membrane). Various

materials have been used for this membrane including earth materials, concrete, steel,

asphaltic concrete, and wood. Rockfill dams may be classified into three groups, depending

on the location of the membrane (USDI, 1987):

1. Central core,2. Sloping core, and3. Upstream membrane, or decked.

Each membrane location has its advantages and disadvantages, which vary according to thetype of membrane, materials available at the site, and foundation conditions. Central and

DAMS

Permanent Provisional

Rigid Flexible Flap gate Vertical lift gate

Fill/Embankment

Rockfill

Gravity

Hollow/Cellular

Arch

Figure 4.1: Dams classification (Source: Dimitriou, 2006)


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sloping cores, which are internal membranes, are generally constructed of impervious earth

materials. An economic analysis should be carried out in order to determine the type of

material to use in constructing the membrane, whether it is internal or external (USDI,

1987). If an internal membrane is selected, a central vertical core is recommended. This

type of core provides maximum contact pressure with the foundation and requires less strictconstruction control than a sloping core. On the other hand, if an external membrane is

used, it should be constructed of concrete, asphaltic concrete, or steel.

Figure 4.2: Membrane types of dams (Source: USDI, 1987)

Rockfill dams use rock of all sizes to provide stability and an impervious membrane to

provide watertightness. The construction of a RCC dam also includes the diversion, the

ground discharge, the spillway and the importation works. The sealing of the foundation is

accomplished by the construction of a grout curtain, while in some cases a seal membrane

is used (Breitenbach, 2004a). In order to prevent the damage or destruction of the dam by

the overflow of water, they have a spillway of adequate capacity. Spillways are provided

for storage and detention dams to release surplus water or floodwater that cannot be

contained in the allotted storage space. The foundations of rockfill dams are not subjected

to settlements large enough to rupture the watertight membrane (Breitenbach, 2004b).


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Therefore, the only suitable foundations are rock or compact sand and gravel that are

abundant in the case of the Aegean Islands. Elimination or reduction of transportation

expenses for construction materials, particularly those used in great quantities reduce the

total cost of the project considerably. The most economical type of dam is often that for

which a large quantity of materials can be found within a reasonable distance from the site(USDI, 1987). The existence of the main foundation materials in a specific place can

significantly reduce the construction cost, and that is the reason most dams in the Aegean

are made of RCC. Likewise, except for the low initial cost that RCC dams have, they also

need small construction lead times in comparison with those of other types of dams

(Efthimiou & Theodoropoulos, 1997).

The operational costs of dams comprise mainly energy requirements (in case that there is a

water treatment plant) and human resources costs. The scheduled maintenance mainly

concerns inspections from experts during rapid filling of the reservoir in the downstream

slope of the dam or foundation contacts that should carefully be inspected at specified

intervals for indications of abnormal condition. During periods of sustained high reservoir

level, particular attention should be given to inspecting the visible portions of the upstream

face of the dam, crest, downstream face, abutments, and areas downstream from the dam

for evidence of abnormal development. Also, the earth embankment of dams should be

inspected at regular intervals for evidence of the development of unfavorable conditions.

The frequency of inspections may be decreased after several seasons of operation if no

abnormal conditions have been observed(USDI, 1987). Therefore, the operational cost for

the oldest dams (for irrigation and/or industrial use) is significantly low or negligible. Also

occasionally maintenance may be needed after all unusual occurrences, such as sustained

periods of high-velocity winds, low infrequent reservoir conditions that expose features

normally submerged. However, if the uses of water from a dam are expanded to include

potable, it will be necessary to install a water treatment plant in order to transform the water

from the dam into high quality drinkable water. The construction of the WTP, namely the

water treatment works (WTW), will add a significant investment cost due to the WTP and

operational cost due to the energy requirements. The construction of a WTP is an

independent project that presupposes an additional investment and operational cost

definition of the parameters to both dams and ground water reservoirs.


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The following methods are the most commonly used water treatment technologies:

(Cheremisinoff, 2002)

1. Physical methods:a.

Heat

b. Reserve Osmosisc. Distillationd. Micro filterse. Sand filtersf. Other filtration methodsg. Activated Carbon

2. Chemical treatment:a. Chlorideb. Iodinec. Silverd. Potassium Permanganatee. Coagulationf. Flocculation

3. Energy intensive technologies:a. Ozoneb. UV Lighty

Ground water reservoirs / conservation storage reservoirs:

The term water ground reservoir / conservation storage reservoir characterizes an individual

type of reservoir that is constructed ordinarily out of the water river bed or at specific areas

where the relief allows for the installation of the water storage reservoir with limited

magnitude of land works. The conservation storage reservoir structure made by

constructing a dam, embankment, or pit, while its purpose is to conserve water by holding

it in storage until it is used either to meet crop irrigation requirements or industrial and

other secondary urban uses (Ogibin, 1968).


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The reservoir may be a natural or artificial lake that collects and stores water for a specific

place, village or island in our case. The main purpose of the water reservoir construction

may be irrigation, industrial, or other secondary uses. Nowadays, the alternatives of water

importation via ships and ground reservoirs remain the most popular solutions to the water

scarcity problem of the Aegean Islands. In addition is the solution of ground reservoirs,which have almost no long-term operating cost (Karagiannis& Soldatos, 2007). If we take

into account that most ground reservoirs of the Cyclades and Dodecanese Island complexes

are used to retain both rainwater and spring water, augment the aquifer, supply water for

agricultural applications (Gikas & Tchobanoglous, 2009), and more rarely for urban water

supply, one can note that it is a sustainable and economically profitable solution to the

water shortage problem. Generally, the basic steps of the construction of a ground reservoir

are:

1.) Collecting works,

2.) Pipeline, and

3.) Main reservoir.

Before the study and construction of the conservation storage reservoir in a specific place

starts, a series of mandatory technical requirements should take place that are aimed at the

location area identification. The technical requirements concern: the identification of

utilized agricultural areas, the siting of possible locations of the installation, and finally, the

environmental impact assessment study with a safety audit for possible expropriations and

social impacts (Efthimiou & Theodoropoulos, 1997). Evaluating and exploring the

proposed reservoir requires that attention be given to all factors that affect reservoir

adequacy or use. The principal factors are rim stability, water-holding capability, bank

storage, potential sources of pollution, and effects of borrow removal on stability and

seepage (USDI, 1987).

The collecting works concern a spillway across the water feed. The purpose of the spillway

is to elevate the level of water as well as to collect water. At the settlement of the spillway,

an open channel is constructed, through which can travel the water inducted at the main

water pipeline as long as, before, it has passed through the sedimentation tank. The


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installation is equipped with a sluice valve/gate in order to control the flow and for its

convenient maintenance.

The water is transported from the intake to the storage via the pipeline. The type of the

pipeline may be open section or embedded linear tube (Efthimiou & Theodoropoulos,1997). The selection of the pipeline type should be accomplished according to the data of

the specific project. For example, in the case of uneven terrain the correct selection is to use

an embedded linear tube pipeline. Additionally, the selected solution depends on the quality

of the transferred water. The possible existence of sediment in the water should drive the

project owner to use an open section pipeline in order to have the ability to observe and

clean the water. On the contrary, if the water is sediment free, the adaptable choice is the

embedded pipeline. Generally, the most common pipeline type is the embedded linear tube

through its low flow rate. Also, there are some common problems that appear in rough

areas, such as the Aegean Islands, that have to confront the measures to be taken in the light

of the prevailing circumstances (Parissopoulos, 1994).

As was mentioned above, the main reservoir may be a natural or artificial lake. In the case

of an artificial lake and for the construction of the main reservoir, excavation and side-

extension works are needed. The materials for the construction of the side-extensions are

mainly materials from the excavation, the wider region and borrow areas or quarries if it is

difficult to find the appropriate materials. The construction of the main reservoir also

includes works that will protect the installation against overflow, the discharge of the

reservoir, the water extraction and the air expansion. The most significant part of the

ground reservoir construction is the seal membrane (geomembrane) installation. The term

geomembrane is characterized by thin plastic leaves with extremely low permeability.

The construction materials are persistent synthetic substances from the plastics industry.

Other materials that accomplish the main watertightness operation and comprise primary

substances should not be confused with geomembranes (i.e. insulation layer from

asphalt/cement, aluminum and soil mixture, barrier layers from metal or concrete) (Kollios

& Parissopoulos, 1995). Planning and construction of membranes are not governed by

severe environmental regulations, because the water use from ground reservoirs is mainly

irrigation and other secondary urban uses. Therefore, small amounts of infiltration are


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effectual, however, with the requirement of temporal stability for the operating lifetime of

the installation.

Accountin

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