local water resource assessment in messinia, greece643960/fulltext01.pdf · 2013-08-29 · local...

Master’s thesisPhysical Geography and Quaternary Geology, 45 Credits

Department of Physical Geography and Quaternary Geology

Local water resource assessment in Messinia, Greece

Karin Ekstedt

NKA 812013

Preface This Master’s thesis is Karin Ekstedt’s degree project in Physical Geography and Quaternary Geology at the Department of Physical Geography and Quaternary Geology, Stockholm University. The Master’s thesis comprises 45 credits (one and a half term of full-time studies). Supervisors have been Jerker Jarsjö and Steve Lyon at the Department of Physical Geography and Quaternary Geology, Stockholm University. Examiner has been Karin Holmgren at the Department of Physical Geography and Quaternary Geology, Stockholm University. The author is responsible for the contents of this thesis. Stockholm, 13 June 2013

Lars-Ove Westerberg Director of studies


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ABSTRACT Messinia is a region in Greece renowned for its rich nature, olive agriculture and water

availability. In the light of increasing anthropogenic and climatic pressure, this study assessed

local water resources in catchments in south western parts of the region. The main objectives

were to evaluate the balance between supply and demand, the sustainability of current water

consumption, capacity of further land use intensification and to review local water

management. The method was dual with both quantitative (water balance calculations and

linear modeling) and qualitative (interviews and a questionnaire survey) approaches.

It was confirmed that, on an annual basis, rainfall is comparatively high, there is a surplus of

water leaving the catchments and aquifers are “superfluous”. The climate however, brings

seasonal imbalance and notable shortages during summer that affect operation of local actors,

especially with agriculture and tourism being the principal water users. Unofficial sources

indicated that current consumption may not be sustainable, either because of over-exploitation

or climatic changes, but further studies are required to draw reliable conclusions. Modeling

showed the importance of land management, that unconsidered water consumption may

impact the water balance substantially but also that, while minimizing evapotranspiration,

there is capacity of intensification if water withdrawals are increased. Considering

accessibility, competitive interests and sustainability however, such development is not

necessarily feasible.

The municipal water management appeared to be well established and, given that measures

are taken concerning for example stakeholder integration and regulation of private and

agricultural consumption, there is capacity of handling increasing water stress. Finally,

stressing the crucial role of freshwater availability, the study highlighted the importance of

further hydrological research and thus the need for improved data quality, particularly

regarding river discharge.

ACKNOWLEDGEMENTS First of all, I would like to give big thanks to Jerker Jarsjö and Steve Lyon for more than great

support and supervision throughout the project. Big thanks go also to the NEO (see below)

station managers Nikos Kalivitis (up to July 2012) and Giorgos Maneas who have been really

helpful with a variety of issues. Konstantine Boulolis, agronomist in Gargaliani, also deserves

special thanks for all the valuable information and material provided; during the interview and

in later e-mail conversations. The support from Efstathia Zontanou at Nileas, with the

interview and with collecting questionnaires is likewise highly appreciated. I am grateful also

to Victoras Plevrakis for consultation and pictures and, together with Katerina Mazi and

Magdalini Zampouni, for translations to and from Greek. I furthermore want to mention

Göran Alm and Ingmar Borgström at the department who helped with lending a GPS and

providing data and material respectively. Thanks go also to Iris Claesson, at the Department

of Human Geography, for lending the Dictaphone. Finally, I want to thank TEMES for

providing the data, all that I interviewed and those who filled in the questionnaires and, of

course, family and friends that supported and encouraged me along the way. No report

without all of you.

Karin Ekstedt

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TABLE OF CONTENTS

1. INTRODUCTION .............................................................................................................. 5

1.1 Study objectives ............................................................................................................ 5

1.2 Regional context ........................................................................................................... 5

2. DATA AND METHODS ................................................................................................. 10

2.1 Site description ............................................................................................................ 10

2.2 Data ............................................................................................................................. 12

2.3 Methods ....................................................................................................................... 16

3. RESULTS ......................................................................................................................... 22

3.1 The water balances ...................................................................................................... 22

3.2 ET of local vegetation and olive irrigation ................................................................. 23

3.3 Hypothetical land use intensification .......................................................................... 23

3.4 The interviews and questionnaires .............................................................................. 25

4. DISCUSSION ................................................................................................................... 31

4.1 Performance and uncertainty ...................................................................................... 32

4.2 The current state of local water resources ................................................................... 33

4.3 Local water management ............................................................................................ 37

4.4 Further studies ............................................................................................................. 39

5. SUMMARY AND CONCLUSIONS ............................................................................... 40

REFERENCES ..................................................................................................................... 41

APPENDIX A: STUDIES REVIEWED FOR ESTIMATING ET IN OLV AND NV ......... 46

APPENDIX B: THE QUESTIONNAIRE ............................................................................ 48

APPENDIX C: RESULTS OF MODEL 1 IN GIANOUZAGAS ........................................ 50

APPENDIX D: COMMENTS TO THE QUESTIONNAIRS ........................................................... 51

Karin Ekstedt

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1. INTRODUCTION Freshwater availability is integral to all ecosystems and to all aspects in human societies,

economic as well as social. Therefore shortage can be a major constraint to development. In

the semi-arid Mediterranean region water resources are indeed limited, especially because of

the characteristic of seasonal imbalance in supply and demand that induces scarcity in the

summer months. This is also an area where climate change is projected to decrease water

availability further and where anthropogenic pressures are increasing through growing

population, tourism and irrigation demands (e.g. Tsagarakis, et al., 2003; IPCC, 2007a; b;

Trondalen, 2009).

Thus, understanding and monitoring the hydrological system and the anthropogenic influence

on it, is of high importance in both land and water management in this region (Sánchez-

Canales, et al., 2012). Research is fundamental on all scales and there is a need for

coordination and cooperation, between scientists and with stakeholders and policy makers.

(Cudennec, et al., 2007). From such motivation, this thesis looks at local water resources and

management in the area round Navarino Environmental Observatory (NEO), Greece, that is a

recently started cooperation between Stockholm University, the Academy of Athens and

TEMES S.A. The NEO is located at Costa Navarino, a luxury mixed-use resort being

developed by TEMES, and is meant to gather researchers from all over the world to offer a

platform for studies and knowledge exchange on Mediterranean environments.

1.1 Study objectives This study’s main objective is to evaluate the current state of water resources in three local

catchments in the area of NEO: the Sellas, Gianouzagas and Xerias rivers (see site

description). The study addresses both water availability and demands and an attempt is made

at both reviewing local water resources management and at assessing the situation and

opinion of local actors who deal with, and are depending on, the local water resources. More

specifically, it is investigated i) if there is shortage or surplus of water resources, ii) if current

levels of consumption are sustainable, iii) how local water management is set up and iv) if

management is sufficient to address increasing anthropogenic and climatic pressure in the

area. Also, to address current and future development, the capacity for hypothetical land use

intensification is simulated through simple linear modeling with emphasis on how such

intensification would affect local hydrological systems.

The overall method includes setting up the catchment water balances and modeling, but also

the gathering of information from local stakeholders through interviews and questionnaires

during a long-term stay on location. This dual approach offers a great opportunity of

characterizing local conditions and of identifying up-to-date key points. The hope is that the

thesis will provide an inclusive overview of the local hydrological system and make a starting

point for further water or other environmentally related studies in the area.

1.2 Regional context Costa Navarino is located in the western parts of Messinia in southwestern Peloponnese,

Greece (see site description), an area renowned for its rich nature and prosperous olive

agriculture in which human settlement reaches far back in time. The geography of the region

Karin Ekstedt

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was described in the 19th

century already and a number of physical studies have followed,

often in connection to archaeological investigations such as the “Minnesota Messina

Expedition” (McDonald and Rapp, 1972) and the “Pylos Regional Archaeological Project”

1991-1996 (Zangger, et al., 1997). Investigating local hydrology requires an understanding of

the regional context. Therefore the following sections offer a more detailed presentation of

principal regional parameters: climate, climate change, land use and water management.

1.2.1 Regional climate and water resources

For being under Mediterranean climate, weather in Messinia is relatively humid. Most

precipitation (P) in Greece is brought in by westerlies during winter and Messinia, being

situated on the west coast and on the windward side of the inland mountains, receives

relatively large amounts of rainfall. Annual P averages 1100 mm in this part of Greece but

varies over an elevation gradient starting at circa 800 mm at the coast, reaching 1000 mm

further uphill and around 1600 mm in the higher mountains (Loy and Wright, 1972; Ministry

of Development, 1997). This can be compared to an average of 652 mm over the entirety of

Greece (AQUASTAT, 2013) and to 350 mm round Athens and on the east coast - where the

land is shadowed by the Pindos mountain range extending north-south through the country

(Loy and Wright, 1972; Ministry of Development, 1997; Baltas, 2008).

Despite relatively large amounts, rainfall is still characterized by the Mediterranean

seasonality which is controlled by the north- and southward shift of the large-scale general

circulation systems. In winter, moist air and cyclonic depressions are brought in from the

Atlantic by the Subpolar jet stream and the westerly surface winds, while in summer, a

northward shift places the Bermuda-Azores subtropical high pressure system over the region.

Thus in summer, i.e. June-August, descending and warming air dominates, skies are clear and

P amounts are close to zero. About half the annual P falls in winter December-February,

mostly as rain, and the other half in autumn and spring. Summer thunderstorms are rare in the

region but do occasionally break the summer drought (Loy and Wright, 1972; Giorgi and

Lionello, 2008; Finne, et al., 2011).

Temperature (T) is also bound by the seasonality of the region. Mean T in Messinia is around

11°C in winter and 27°C in summer (Loy and Wright, 1972). Generally along the coasts in

Greece, mean minimum T in January-February is 5-10°C and mean maximum T in July-

August is 29-35°C. Sea breezes cool temperatures along the coasts during summer (HNMS,

2013) yet the intensive incoming solar radiation still causes high potential evapotranspiration

(PET) and atmospheric water demands that clearly exceed P (Fig. 1, after Loy and Wright,

1972). Hence, through the 5-6 months that make up the dry season, roughly April/May-

September/October, evapotranspiration (ET) is controlled by P in combination with soil

moisture and the system is clearly water-limited. Winters offer the opposite, P is rich and low

temperature gives low PET (e.g. Loy and Wright, 1972; Baltas, 2008; Ryu, et al., 2008;

HNMS, 2013).


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P PET ET

1

2

3

200

150

100

50

Figure 1: Constructed graph (fictive numbers)

generalizing the typical annual interplay

between P, PET and ET under Mediterranean

conditions. At point 1 water surplus is ended

and PET exceeds P, ET draws on soil

moisture. At point 2 soil moisture is depleted

and there is a clear water deficit. At point 3 P

exceeds PET again and soil moisture is

recharged. After original water-balance

diagrams from the local area produced by Loy

and Wright (1972), p.39, Fig. 3-1.

Water availability in Greece follows the complex pattern of P and the country is split into

several smaller hydrological regions, ranging from those of intense deficiencies to those of

lasting surpluses (Sofios, et al., 2007; MEECC, 2010). As mentioned, P and therefore also

water resources, are generally richer in the western regions (Kerkides, et al., 1996) and

according to the Ministry of Development (1997), the district of Western Peloponnese has

ample surface- and ground water resources. Ground water flows in particular, are important

for water transport in this type of climate and landscape (Newman, et al., 1998; 2006). The

geological structure of Messinia, with limestone, sandstone and conglomerates, is favorable

for ground water generation and the mountain headwaters make up good catch basins (Loy

and Wright, 1972; García-Ruiz, et al., 2011). As a result, there are numerous springs at lower

altitudes and ground water can be easily extracted in wells. This is important for feeding the

extensive irrigation systems as well as for the drinking water supply, particularly in the

summer drought when most rivers run dry (Loy and Wright, 1972, MEECC, 2010).

1.2.2 Climate change and water resources

Numerous studies have reviewed the characteristics and impacts of climate change in the

Mediterranean region. It is identified as one of the primary “Hot-Spots” (Giorgi, 2006) and

most responsive and vulnerable regions to climate change globally (e.g. IPCC, 2007a; Giorgi

and Lionello, 2008; Trondalen, 2009; Bosello, et al., 2013). Greece moreover, is among the

areas identified as particularly affected in the Mediterranean region (Diffenbaugh, et al.,

2007). Substantial climate changes are projected with evident consistency in most models and

recent studies show that shifts are already occurring (e.g. Kostopoulou and Jones, 2005;

IPCC, 2007a; b; Mavromatis and Stathis, 2011).

In short, with global warming a “pole-ward extension” is expected of the seasonal shifts in

latitudes of the global circulation system. This means the Bermuda-Azores anticyclonic cell

will become more dominant and long-standing in the region. The dry summer season will thus

be prolonged and intensified and winter low pressures hampered and moderated (IPCC,

2007a; Giorgi and Lionello, 2008). Accordingly, P is confidently projected to decrease,

especially during summer and in terms of the number of rainy days in winter. IPCC (2007a)

Karin Ekstedt

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for example, predicts a total decrease in average P of 7-27% until 2090-2099 in the

Mediterranean (assembled models, SRES scenario A1B, reference period 1980-1999). The

corresponding modeling for T projects an increase of 2.2-5.1°C and particular warming in

summer. Many studies also point to higher rainfall intensity, higher interannual variability in

both P and T and a higher frequency and severity of extreme hot and dry weather conditions

(e.g. Diffenbaugh, et al., 2007; IPCC, 2007a; Trondalen, 2009; MEECC, 2010; Sánchez-

Canales, et al., 2012).

Naturally then, most models predict a decrease in runoff and ground water infiltration in the

Mediterranean basin (Trondalen, 2009; MEECC, 2010). This has, again, been confirmed in

several studies to occur already (e.g. García-Ruiz, et al., 2011; Mavromatis and Stathis, 2011).

IPCC (2007b) predicts a decrease in runoff of 0-23% until 2020 and of 6-36% until 2070 in

southern Europe (reference period 1961-1990). Together with increased interannual

variability, and a higher frequency and severity of droughts, this will cause notable

disturbances in hydrological systems altering the regime, quantity, quality and sustainability

of water resources. Environmental and social impacts extend also to for example forest fires,

losses of biodiversity, desertification and also effects in general health, tourism and energy

consumption (e.g. IPCC, 2007b; Trondalen, 2009; FAO, 2011; García-Ruiz, et al., 2011).

1.2.3. Land use and water resources

Both natural and anthropogenic changes in land cover and land use are also particularly

intense in the Mediterranean landscape, as they have been for the past 10 000 years (García-

Ruiz, et al., 2011), and many studies have shown related impact in the hydrological systems.

Particularly, vegetation has large influence on evapotranspiration and infiltration that affects

the quantity, quality and regime of rivers and aquifers (e.g. Brown, et al., 2005; Bhattarai, et

al., 2008; García-Ruiz, et al., 2011; Sánchez-Canales, et al., 2012). The actual influence will

always depend on specific catchment characteristics, such as soil water storage capacity and

climatic conditions, and new equilibriums can take many years to reach after permanent

changes occur (Bosch and Hewlett, 1982; Brown, et al., 2005).

In the Mediterranean, climatically induced water scarcity is projected to cause considerable

changes in land use and specifically, a decrease and degradation of arable cropland is

expected (e.g. MEECC, 2010; IPCC, 2007b; FAO, 2011; García-Ruiz, et al., 2011).

Agriculture has always been the main feature in Greek economy (Loy and Wright, 1972).

Sugar beets and olives dominate production and, after Spain and Italy, Greece is the third

largest producer of olives in the world (FAOSTAT, 2011). Due to the climatic conditions,

irrigation in Greece already accounts for 84% of total water consumption (MEECC, 2010) and

demands are increasing, partly also following growing markets for olive products and

intensification in agriculture (e.g. Metzidakis, et al., 2008; Iniesta, et al., 2009; Nainggolan, et

al., 2012). In Greece alone, the proportion of irrigated fields increased 22% 1990-2006

(MEECC, 2010).

Olive trees are resistant to drought and have long been cultivated in low density orchards

using rainfall only. New orchards however, are streamlined with higher density, less alternate

bearing behavior and effective drip irrigation (Beede and Goldhamer, 1994). Increasing water


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demand however, poses an issue in water management and is a limiting factor for alternative

uses (Bosello, et al., 2013). Research is becoming progressively focused on estimating and

modeling specific and local irrigation requirements and it is crucial for sustainability that land

use and irrigation management is adapted accordingly (e.g. Orgaz, et al. 2006; Testi, et al.,

2006; Metzidakis, et al., 2008).

Coastal regions in the Mediterranean are under additional pressure from for example tourism

(which just like agriculture is an important feature in Mediterranean economies), denser

population and industry and, in addition, future scenarios indicate further intensification.

Tourism and agriculture in particular, cause seasonal imbalance in supply and demand that

above all generates large deficiencies in summer. It is not uncommon that aquifers here are

intensively and unsustainably exploited, not least along Greek coastlines, and that the issue of

salt water intrusion emerges (e.g. Cudennec, et al., 2007; MEECC, 2010; García-Ruiz, et al.,

2011; Mazi, et al., 2013). Increasing salinity, together with intense fertilization and use of

pesticides in agriculture, deteriorates water quality and affects all users in these areas (NTUA,

2007; Baltas, 2008).

1.2.4 Water management in Greece

There have been recent large-scale reorganizations in Greece restructuring a fragmented and

decentralized institutional framework with the merging of municipalities into larger units as

one of the main outcomes. Up until 2011 the former Ministry of Environment, Planning and

Public Works was the main body for environmental and water management (Tsagarakis, et

al., 2003) yet in the new system, water management is governed under the National Water

Commission chaired by the Ministry of Environment, Energy and Climate Change (MEECC).

The Special Secretariat for Water is then the body responsible for planning and coordinating

implementation between national and regional levels (MEECC, 2009).

There are 14 Water Regions in the country, with their own departments for water and waste

water, that are responsible for regional implementation of the national strategic planning

(Tsagarakis, et al., 2003; MEECC, 2009). Actual measures and management however is run at

municipal level. Most commonly, in municipalities with more than 10 000 inhabitants (and in

some with fewer), water is managed by the “Municipal Enterprise for Water Supply and

Sewage” (DEYA). There are now more than 200 DEYA in Greece and they serve about 35-

40% of the total population. The bigger cities of Athens and Thessaloniki have similar yet

somewhat different solutions and smaller municipalities cover management themselves

(Tsagarakis, et al., 2003; Safarikas, et al., 2006).

The DEYA is owned by the municipality and partly financed by the state yet it is run as a

private company rendering the enterprise flexible and efficient in its operation (Tsagarakis, et

al., 2003; Safarikas, et al., 2006). It owns the facilities, sets the water tariffs according to

operation costs and independently determines their extent of cooperation with private

companies. In effect it is responsible for constructing, maintaining and running local networks

for water supply and sewage and for verifying that quality is sufficient for environmental and

health requirements (Tsagarakis, et al., 2003).

Karin Ekstedt

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The DEYAs in Greece typically face several challenges, for example with loans, distributing

networks and sewage systems requiring expensive upgrades, inadequate monitoring,

increasing anthropogenic development and increasing quality issues in local water resources

(Tsagarakis, et al., 2003). In this context there are several studies that point to the importance

of strong institutional frameworks with political and economic stability, fewer water districts

(preferably at watershed-level as is set in the EU Water Framework Directive (WFD)) and

clear guidelines and assignment of responsibilities. Also commonly emphasized is the

significance of stakeholder integration; for information-sharing, for prevention of mistrust,

conflict and unawareness and for fair decision-making. This is particularly important

considering external political regulation commonly interferes with economic interests (e.g.

IPCC, 2007b; Baltas, 2008; García-Ruiz, et al., 2011; Bosello, et al., 2013). As mentioned, a

new legal framework is being developed in Greece in order to facilitate the enterprises and

water legislation is under continuous adjustment in correlation with the EU WFD (Tsagarakis,

et al., 2003) - which was the focus of the first meeting of the National Water Commission in

2010 (MEECC, 2009).

2. DATA AND METHODS

2.1 Site description Sellas, Gianouzagas and Xerias are three main rivers draining into the sea along the coast

between Costa Navarino and Pylos. Their headwaters are typically in the inland mountainous

areas where elevations reach more than 1000 m (Tab. 1a) but closer to the coast topography

levels out and the rivers flow through plains of fertile agriculture before reaching the sea (Fig.

2). The Sellas catchment is roughly twice the size of the Gianouzagas and Xerias catchments

and it also covers higher altitudes than does the other two.

The dominating land use in this area is olive agriculture (OLV). It covers around 70% of the

total catchment area in Sellas and Xerias and almost 90% in Gianouzagas (Tab. 1b). Other

vegetation, summed under “native vegetation” (NV), is diverse and includes coniferous,

broadleaved as well as sclerophyllous vegetation. Sparsely vegetated areas and shrubs are also

common but bare land and artificial surfaces cover no more than 1.5% in either of the

catchments (Lundholm, et al., 2009). Typically, geology is mainly made up of sandstone and

limestone while alluvial deposits dominate at the coastal plain between Gialova and

Romanos.

Table 1: Physical characteristics of the catchments: a. altitude statistics: average (avg) (also in Tab. 2),

standard deviation (std), minimum (min) and maximum (max) and b. areas: the total catchment, olive

agriculture (OLV) and “native” vegetation (NV).

a. Altitude statistics, masl b. Areas, km2 (%)

Avg std min max total OLV NV

Sellas 370 194 6 1041 87.7 65.2 (74) 22.6 (26)

Gianouzagas 268 100 20 703 39.0 34.7 (89) 4.4 (11)

Xerias 201 96 9 823 47.7 33.6 (70) 14.1 (30)


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Figure 2: The three catchments, the local rainfall (P) and discharge (Q) gauging stations, local

villages, the two development sites of Costa Navarino, land use (Lundholm, et al., 2009) and elevation

relief (Delrue, unpubl.).

At this alluvial plain lies Gialova (Osmanaga) lagoon which is perhaps the most prominent

environmental feature in the area. It is an important wetland for more than 271 species of

residential and migratory birds and it is the only European residence for the African

chameleon (TEMES S.A., 2009a). Through the past decades however, it has been under much

anthropogenic pressure from for example freshwater withdrawals in agriculture, exhaustive

fishery, drainage and increasing infrastructure (HOS, 2013). The lagoon was formed gradually

Coordinate System: WGS 1984

Projection: Mercator Auxiliary Sphere

Land

useand

use

Land use

Karin Ekstedt

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through the successive steps of barrier formations that shaped Navarino Bay the last 9000

years. Today the floodplain is an inactive erosional environment but it was previously fed

with massive amounts of sediments from the Sellas River. The river was diverted just north of

Romanos during the Late Bronze Age (in the Mycenaean Era, 1600 BC - 1100 BC) in a

hydraulic project that created a clean water port for the palace of Nestor - the first known

artificial harbor installation of its size in Europe (Zangger, et al., 1997).

The area has been of high significance and both a cultural and demographic center through

history yet at present, it is a remote and rural area and population density is low (Zangger, et

al., 1997). NEO and Costa Navarino are located in the municipality of Pylos-Nestor, formed

from merging 6 former units in 2011, that has a population of 21 077 (38 people per km2, total

area 555 km2) and in which the main city is Pylos with 2 350 residents (ELSTAT, 2012). The

municipality has an oblong shape stretching from Palea Vrisi in the north to Koroni in

southeast. All in all, the area has high environmental and recreational values that make it an

attractive destination for tourism. Hitherto there has still only been little tourism yet the recent

establishment of Costa Navarino could make a turning point for such development. The resort

is likely to attract not only thousands of guests but also further local business and settlement

that will increase anthropogenic pressure on natural resources, such as water.

2.2 Data The water balances for the three catchments (see method section) were set up using local

discharge (Q) and P data series measured and provided by TEMES through NEO. They were

reported every 15 minutes and the longest records covered January 2009 to October 2012

(Tab. 2). There were six meteorological stations around the catchments (Fig. 2) that were set

up in a network by TEMES in 2008 to monitor for example T, humidity and wind speed. P

was gauged using weighing buckets and both missing data and outliers did occur in the series.

Q was measured in the rivers of Sellas, Gianouzagas and Xerias respectively (Fig. 2 and 3)

using an optical radar technique (Fig. 4). It was reported as an “instrument to water surface

distance” that was converted to a depth and rated into discharge. However, no explicit

information on the “instrument to river bed distance” was provided such that it was necessary

to assume it equal the highest “instrument to water surface distance” reported.

Under an initial quality control check the daily streamflow data series from Sellas appeared to

be the most reliable among the three. It had the most continuous record and a hydrograph

reflecting the expected river regime (Fig. 3). Gianouzagas on the other hand had very short

time coverage and its hydrograph, particularly considering i) the unexpectedly steady flows in

November 2010 - February 2012 and ii) the peculiar drop in March and April 2012, indicates

that the measurements were affected not only by natural factors and that there were errors

inherent in the observations.


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Table 2: P and Q gauges set up by TEMES, their station names, time coverage, mean altitude and

average annual P or runoff (R, see below) respectively. Brackets in the last column give Q in m3/s.

Parameter Station Time period Altitude, m P/R (Q), mm/yr

P

Navarino Sep10 – May12 34 694

Moyzaki Jan09 – May12 436 1151

Chora Jan09 – May12 237 766

Handrinos Jan09 – Oct12 184 895

Sgrapa (Gialova) Jan09 – Oct12 14 660

Kynigos Jan09 – Oct12 311 880

Q

Sellas Jan09 – May12 370 378 (1.05)

Gianouzagas Jan09 – Apr12 268 392 (0.48)

Xerias Oct10 – May12 201 1602 (2.42)

The Xerias data series contained much missing data, several unaccountable extremes

(sometimes exceeding 70 m3/s) and reported values of questionable accuracy (see July-

October 2009 for example). For relevant presentation in Fig. 3, extremes have been cut and

missing data replaced by monthly averages. Because of data shortage and lack of reliability in

the records of Xerias, these monthly averages were estimated through correlation with Sellas:

the proportional relation between the monthly and the annual average “instrument to water

surface distance” in Sellas was applied to the annual average in Xerias thus giving an

approximation of the corresponding monthly values. The correlation was justified given i) the

spatial proximity, ii) the assumption of similar hydrological regimes and iii) the statistical

similarity of the monthly average measurements in the two catchments despite deviation some

months (the annual average/standard deviation of the “instrument to water surface distance” is

302/11 and 366/16 mm in Sellas and Xerias respectively).

It should be mentioned that the data available for constructing rating curves in the three

catchments were limited to six (three in Xerias) monthly average water levels and their

corresponding Q values in January-June 2012 only. These were presumably measured at the

same cross section as where the daily data was collected. Also, from personal communication

with local sources and observation on location it appears that the river beds are unstable with

erosion and sedimentation of up to 30 cm or more at times. Water is furthermore transferred

to surface water reservoirs (see the result section) from all three rivers (TEMES S.A., 2009b).

To our knowledge however, Q is measured upstream from these artificial outlet points so they

should not have influence over the resultant water balance.

Karin Ekstedt

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Figure 3: The hydrographs of the three rivers with the set hydrological years marked with

crosshatched vertical lines. In black is runoff (R, see below) and in blue the catchment precipitation

(P, on the secondary y-axis), both in mm/yr. Notice that the vertical axis for R in Xerias has a larger

scale than the other two. For legibility extremes of R have been cut in Sellas (2176 mm/yr the 7

February 2012) and Xerias (several, with the highest being 49 114 mm/yr (!) the 28 December 2009).

0

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For other spatial analyses there was also a digital elevation model (DEM) with a resolution of

30 m and a land use shape file available from previous studies performed by Delrue (unpubl.

data) and Lundholm et al. (2009) respectively (Fig. 2). The catchments were delineated, and

their areas estimated, using the DEM and hydrological tools in ESRI ArcGIS. The same

software was used for evaluating the land cover distributions in the catchments, as based on

the land use shape file. This land use map was made on a regional scale covering the whole of

Messinia hence it gives a rough estimation of local distribution only. It should be noted that

because the exact locations of the Q gauges were not specified, there might be an offset of

these to the delineation points.

Figure 4: (a) Local meteorological

station measuring for example T and

P and (b) the radar instrument used

for measuring river stage. Photo

courtesy: TEMES (a) and Victoras

Plevrakis (b).

Finally, there was information provided by Konstantine Boulolis, an agronomist active in

Gargaliani (a city 7.6 km from Costa Navarino located outside the municipality of Pylos-

Nestor, see Fig. 2), on approximate irrigation amounts applied seasonally in the local olive

orchards. This estimation was based on his experience and on “irrigation diaries” filled and

turned in by his client farmers reporting field characteristics, dates, duration and volumes of

irrigation (Fig. 5). Importantly, this is an approximation of applied amounts only.

Figure 5: Example of an irrigation diary filled in by a local farmer and collected by agronomist

Konstantine Boulolis in Gargailianoi, Messinia. The first column gives the field ID, the second and

third the date and hours of irrigation respectively and the fourth the quantity of water for each tree

(translation Magdalini Zampouni). Field characteristics are given in a separate form.

(a) (b)

Karin Ekstedt

16

2.3 Methods

2.3.1 The water balances

There is no limit to the possible complexity of water resources modeling. Data demands and

uncertainty increase rapidly the more comprehensive the evaluation and the higher the

number of parameters included. The water balance is a straightforward method for evaluating

water availability with little data yet sufficient accuracy. It can be used on any temporal and

spatial scale, yet again; the finer the resolution the higher the demand for detail and precision.

Depending on the assumptions made, the water balance equation can be set with varying

complexity but the basic concept is for inputs to the water system to equal outputs. Assuming

no trans-boundary transfer of water, the balance can be written as:

where P is precipitation, ET evapotranspiration, R runoff ( ), ΔS

change in storage (including ground water, soil moisture, snow/ice and lakes/rivers/reservoirs)

and μ is the balance discrepancy (preferably close to zero) (Senay, et al., 2011). For large

spatial scales and long time periods this equation can be reduced into:

while assuming:

(1) The change in storage is zero. This assumption is (most often) valid when studying

long time series, at least one year, where temporal variability is balanced (i.e. the

system approaches an approximate steady state). The longer the time considered the

greater the power of this assumption. When using this form for shorter time periods,

such as for individual months, contributions due to ΔS cannot be ignored.

(2) The discrepancy (uncertainty and errors) is negligible and “embedded” in the

parameters left.

Evapotranspiration is difficult to measure and is more conveniently evaluated as the residual

that closes the balance. Eq. 2 is therefore rearranged into:

which was the simple equation employed in this study on catchment scale and on an annual

basis.


17

Ideally the annual water balance would be evaluated for the hydrological year (HY) starting in

September when discharge is lowest. However, in order to use the available time period of

data optimally, the HY was set to start in May (HYMay). Annual catchment P was estimated

through inverse distance weighed averages (IDWA) i.e. through weighing the nearest gauges

(Tab. 3) according to their proximity to the catchment center. Thus, the closer the gauge the

greater was the influence on the average. Orographic variance caused uncertainty in

interpolation and there was a lack of gauging stations at higher altitudes where P was richer

(Tab. 2 and Fig. 6). Moyzaki was the closest equivalent with the highest P and was therefore

given additional weight when estimating P in Sellas. For the same reason, i.e. better

representation of the orographic setting, both Navarino and Sgrapa stations were excluded

completely from the calculations.

Table 3: The stations (x) used for the IDWA estimations in each catchment.

Navarino Moyzaki Chora Handrinos Sgrapa Kynigos

Sellas - x x x - -

Gianouzagas - - x x - x

Xerias - - - x - x

Figure 6: Annual average precipitation (HYMay, 2009-2012 or the time available) as a function of

altitude at the local meteorological stations set up by TEMES.

Navarino

Moyzaki

Chora

Handrinos

Sgrapa

Kynigos

500

600

700

800

900

1000

1100

1200

0 100 200 300 400 500

An

nual

P

(mm

)

Altitude (m)

Karin Ekstedt

18

2.3.2 ET of local vegetation

The ET of local vegetation was required for subsequent land use modeling. For simplicity and

relevant accuracy (especially with the crude land use map available), the current land cover

was classified into two categories only, again: olive agriculture (OLV) and “native”

(other) vegetation (NV). These were then characterized by their different ET values, initially

taken from literature. All studies reviewed for this purpose (Fig. A1 and marked with asterisks

in the reference list) were performed in Mediterranean climate, either in the Mediterranean

countries or in California (one in Arizona), U.S. The primary methods employed were i) eddy

covariance measurements, ii) different kinds of modeling or iii) water balance approaches. All

in all, 21 reported annual numbers were noted and averaged into approximate representative

ET values for both OLV and NV.

These literature values were then calibrated to local conditions and scaled to the three

catchments. This was possible with the underlining assumption that the relative distribution

(represented as a ratio, rlit, Eq. 4) between the literature ET values of regional OLV and NV

(ETo_lit and ETn_lit respectively), applies also to the local area. Scaling was done through

combining this ratio with the ET balance in each catchment (Eq. 5). This balance states that:

the total volume of ET (ETt*At) from the catchment, which was estimated in the water balance

(Eq. 3), equals the summed ET volume from OLV and NV (Ax*ETx). Eq. 4 and 5 were

rearranged and combined into Eq. 6, in which ETn in the local catchments can be

approximated. Based on this result and Eq. 4, ETo was then estimated in a fourth and final

step (A = area, t = catchment total, o = OLV and n =NV).

⁄

)

⁄

2.3.3 Hypothetical land use intensification

Focus then fell on possible land use change and on how the introduction of an additional

highly evaporative vegetative cover would affect the current land use - and water balances.

This hypothetical land cover (HYP) was assumed to have an ET (ETh) close to PET (scenarios

A-C, Tab. 4) resulting from any intensive land use with for example high water demands

and/or exhaustive irrigation. The PET was correlated to literature (average of all studies

reviewed is 1240 mm/yr) but also to local Priestly-Taylor modeling performed in the Sellas

catchment (again 1240 mm/yr) (Klein, unpubl.). Two opposite alternatives of water

management were addressed when introducing HYP: that of maintaining the current

(presumably) sustainable water consumption (Model 1) and that of consuming surface water

until no basin outflow remains (Q = 0) (Model 2). Of course there exists a range of plausible

water exploitation between these yet focus here is on the end-point scenarios.

Table 4: The three scenarios, A, B and C, of ETh in mm/yr. Scenario C resembles PET, A is set to a

lower value close to P (average for all three catchments is 893 mm/yr) and B is their average.

A B C

ETh, mm/yr 900 1075 1250


19

Model 1

Model 1 returned what measures are required in land management regarding the areas of OLV

and NV, to compensate for HYP and maintain the current water balance. The principal

underlining base (Eq. 7) of the model was the same as in Eq. 5 yet here also HYP was

included (ETh*Ah). Eq. 8 offers a way of substituting for the area of NV (An) through the fact

that all sub-areas add up to the total area. It was used also for back-calculating An after

retrieving the decreased area of OLV (Ao) in Eq. 9. This equation originates from combining

Eq. 7 and 8 and then solving for Ao.

⁄

Model 2

Model 2 addressed the theoretical capacity of accommodating HYP before ET exceeds P if

river flow (Q) would instead be completely exhausted for satisfying the HYP water need. It

was set up based on the same ET-balance as in Model 1 only this time, the initial land use

distribution was considered plus P replaced ETt on the left-hand side since Q was added to

total availability. It was run in two sub-sets assuming that i) the HYP replaces all NV first and

then OLV (case 1, Eq. 10-11) and ii) only OLV is replaced by the HYP (case 2, Eq. 12-13).

Eq. 11 and 13 originates from solving for Ah_max in Eq. 10 and 12 respectively.

( )

( )

In both models (Eq. 7-13) it was assumed that:

(1) PET, and thus ETh, was the same in all three catchments despite possible difference in

their water balances. This should be justified considering the dependence of PET on P

and T primarily, which both have low spatial variability.

(2) The ratio between ETo and ETn as derived from literature was the same in all three

catchments, which presupposes plants and their physical conditions were similar.

Applying literature values in the first place is a considerable source of uncertainty that

will be addressed in later discussion.

(3) ETn was representative of all “other” land uses than olive agriculture.

(4) Ah increased with a percentage of the total and respective catchment area, rather than

with a set magnitude equal in all three catchments.

Karin Ekstedt

20

(5) The 2009-2012 average P and ET values were representative for the long-term

regional conditions.

(6) There was no transboundary exchange of water between the catchments.

2.3.4 Interviews and questionnaires

The qualitative assessment of water resources was performed by reviewing literature,

distributing questionnaires and through simple interviews with concerned actors on location

(Tab. 5). The purpose was to investigate how local water resources are managed, what the

dominating water uses are and what “pressures” exist on water availability - between different

actors and in current and future development. The interviews were set up in an open semi-

structured way collecting a narrative and leaving open the possibility of adapting questions

and discussions to the interviewee. A Dictaphone was brought for the interviews but

functional issues unfortunately hindered recordings.

The questionnaire (Appendix B) was put together with the purpose of gathering general

thoughts and opinions from local residents and actors. It was made available both in English

and Greek (translation to Greek by Katerina Mazi). Tab. 6 lists the occupation, gender, age

and residence city of the contributors that filled in the questionnaire. Most have connection to

agriculture (two agronomists and 12 farmers), some are active at Costa Navarino and NEO (8

people) and the rest are “other” local stakeholders. Most interviews and questionnaires were

collected on location in June-July 2012 but answers were also brought in afterwards via e-

mail.

Table 5: Interview dates and the names and occupation/position of the people interviewed.

Date Name Occupation/position

9 July 2012 Efstathia Zontanou Supervising agronomist at the producer’s group Nileas,

Chora

10 July 2012 Giorgos Maneas Station manager at NEO from June 2012, former head of

the HOS* Gialova lagoon project

28 July 2012 Konstantine Boulolis Agronomist, Gargaliani

10 July 2012 Panagiotis Andrianopoulos

& Nikitas Crikas General and technical managers at DEYA Pylos**

17 July 2012 Vasilis Karakousis Environment and sustainability manager at TEMES

*The Hellenic Ornithological Society, runs environmental protection work at Gialova lagoon among many other

things.

** ΔΕΥΑΠ, public-service corporation responsible for drinking water supply and waste water treatment in the

municipality of Pylos- Nestor.


21

Table 6: Name, occupation, gender (1=female, 2=male), age and city of residence of the individuals

that filled in the questionnaires in the order of collection (CN = Costa Navarino).

Name Occupation Gender Age Residence

1 Konstantine

Bouloulis Agronomist 2 42 Gargaliani

2 Theodoras

Kostadopulos Farmer 2 38 Gargaliani

3 Panagiotis

Panagiotopoulos Farmer 2 54

Floka (ΦΛΟΚΑ)

(Gargaliani)

4 Helen Boulouli Farmer 1 - Gargaliani

5 Ioannis Boulouli Farmer 2 - Gargaliani

6 Ioanna

Karamichalou Buisiness woman 1 47 Gialova

7 - Restaurant owner /

merchant 1 50 Gialova

8 Ioannis Lopas Pharmacist 2 50 Romanos

9 Dimitrios Kajas Agronomist 2 40 Chora

10 - Farmer 2 32 Pyrgos (north)

11 - Farmer / gym teacher 2 44 Chora

12 - Private employee 1 33 Chora

13 Giorgos Melcher Electrical engineer at CN 2 52 Gialova

14 Heleni

Georgiopoulou

Student and farmer’s

daughter 1 20 Chora

15 Dionisis Sampolis Farmer 2 58 Filiatra

16 Nikos Kalivitis Physicist, former NEO

station manager 2 35 (Crete)

17 Giorgos Maneas NEO station manager,

former head of HOS 2 32 Kalamata

18 Dimitrakopoulos

Takis Farmer, Nileas 2 49 Chora

19 - Farmer, Nileas 2 58 Chora




23 Raphaella Tsianti Hotel employee, CN 1 - Pylos

24 - Hotel employee, CN 1 29 Marathopoli

25 - Civil engineer, CN 2 42 Kalamata

26 Georgia (Vlahou) Director of conventions

and events, CN 1 52 Greece

27 Natasa Glaraki Assistant to the Chief

Destination Officer, CN 1 32 Kalamata

Karin Ekstedt

22

3. RESULTS

3.1 The water balances The annual water balance (Eq. 3) for the three considered catchments are shown in Fig. 7 and

Tab. 7 below. Because the estimated R in Xerias (averaging 1602 mm/yr) exceeds rainfall

input, the water balance cannot be closed and the catchment is therefore not considered in

further analysis. In Gianouzagas, time coverage and data quality are clearly limited. However,

average water balance terms HYMay 11-12 (HY3) are similar to Sellas, which indicates that

available data are consistent.

P data is available throughout the whole period and annual patterns of rainfall are similar

across all catchments. Comparing the hydrological years, HY3 is generally the wettest, HYMay

10-11 (HY2) the driest and HYMay 09-10 (HY1) is closer to the average of the three years. The

interpolated annual average P across all the catchments is 893 mm and spatial difference

(averaging 39 mm) is smaller than the interannual (averaging 97 mm).

Figure 7: The water balance parameters of the three catchments HY1-3: P (black), R (crosshatched)

and ET (white). Notice that the vertical axis for Xerias has a larger scale than the other two. All values

are in mm.

Table 7: The actual water balance values (P, R (% of P) and ET estimated as P minus R) in the three

catchments. All values are in mm/yr.

Sellas

Gianouzagas

Xerias

HYMay P R ET

P R ET

P R ET

09-10 891 416 (47) 476

862 - -

915 2148 (235) -

10-11 834 302 (36) 532

839 - -

812 1166 (144) -

11-12 1024 416 (41) 608

928 393 (42) 535

930 1483 (159) -

Average 916 378 (41) 539

876 392 (45) 484

886 1602 (181) -

0

200

400

600

800

1000

1200 Sellas

P

Q

ET

0

200

400

600

800

1000

1200 Gianouzagas

P

Q

ET

0

400

800

1200

1600

2000 Xerias

P

R

ET

Am

oun

t o

f w

ater

(m

m)


23

3.2 ET of local vegetation and olive irrigation Tab. 8 shows a summary of the average ET in OLV and NV obtained through the literature

review and the estimated catchment ET values reached after water balance closure and

calibration. As can be seen, OLV has 1.78 times the ET of NV in this type of climate and, even

if they differ from the regional estimations, the calibrated catchment numbers are fairly

similar in the two catchments of Sellas and Gianouzagas. ETo and ETn in Gianouzagas amount

to 93% of the same values in Sellas while their average is only 80% of the regional

estimation.

Table 8: Regional ET numbers attained from the literature review (ETo_lit and ETn_lit), their ratio (rlit)

and the ETo and ETn scaled to the catchments of Sellas and Gianouzagas respectively. All values apart

from the ratio (no unit) are in mm/yr.

Regional Sellas Gianouzagas

ETo_lit ETn_lit rlit ETo ETn ETo ETn

730 410 1.78 607 341 563 316

In the literature reviewed were also estimations of applied irrigation amounts, all in the

Mediterranean region. These range from 181 mm/yr (Fernández, et al., 2006) to 403 mm/yr

(Palomo, et al., 2002) and averages 300 mm/yr (additionally: Fernández, et al., 1998; Orgaz

and Fereres, 2004; Pastor, 2005; Tognetti, et al., 2006). Also, the average tree density is 223

trees/ha. Local olive fields, according to Mr. Boulolis agronomist in Gargaliani, are irrigated

approximately once every second week during the warm and dry season June-September and

then harvested in October-December. Generally and based on farmers’ irrigation diaries, the

average size of a local farm is 1 ha, the tree density is 200 trees/ha and each tree consumes 1

ton of water per 10 days from July to September. Small trees would need half the water. A

rough estimation based on these numbers results in an irrigation amount of around 100-150

mm/yr in the local area (11-17% of total annual rainfall (2009-2012)) depending on land

cover distribution, proportion of irrigated agriculture and proportion of “grown” vs. “small”

trees. The extra water evaporated from OLV in relation to NV (estimated above) corresponds

to 200 mm/yr and 220 mm/yr on catchment scale in Sellas and Gianouzagas respectively.

3.3 Hypothetical land use intensification

3.3.1 Model 1

The primary result of simulation in Model 1 in Sellas is a clear increase in the ratio of An to Ao

(An/Ao) as HYP covers an increasing proportion of the catchment (Fig. 8, upper chart). This

response is similar to that in Gianouzagas (Appendix C and Fig. C1 therein) which supports

consistency in the model results. Common for both catchments also is that An/Ao grows more

rapidly i) the higher the ETh (compare scenario A to B to C), and ii) the larger the Ah

introduced (growth is non-linear). Also, the larger the scale of development the greater is the

influence of ETh.

Karin Ekstedt

24

0

0,4

0,8

1,2

1,6

2

0 5 10 15 20 25

An/

Ao

Ah (% of At)

A

B

C

0%

20%

40%

60%

80%

100%

0 5 10 15 20 25

% o

f A

t

Ah (% of At)

Χ

Χ

Figure 8: 0 < An/Ao < 2 as a function of Ah introduced in the catchment of Sellas under the three ETh

scenarios (A = 900, B = 1075 and C = 1250 mm/yr of ETh) (upper chart) and a stacked area diagram

showing the change in distribution between Ao (white), An (checked) and Ah (black) in scenario C

(lower chart). The markings indicate corresponding points in the upper and lower charts of Ao = An

(An/Ao = 1) and An = 2Ao (An/Ao = 2) respectively.

In accordance with the linearity of the model, Ao and An change with constant rates (Fig. 8,

lower chart). The rate of decrease in Ao (ΔAo/ΔAh) is -2.1 in scenario A, -2.8 in scenario B and

-3.4 in scenario C. This latter value also represents the slope of the boundary separating Ao

and An in the lower chart of Fig. 8. As Ao approaches zero, An/Ao reaches infinity and the

asymptote of the curve will correspond to the Ah theoretically possible before inevitably

affecting the water balance (i.e., violating the conversation of mass assumption inherent to the

approach). In Sellas, this occurs at Ah ≈ 31.1 km2 (35% of At) in scenario A, 23.7 km

2 (27%)

in scenario B and 19.1 km2 (22%, also visible in the lower chart of Fig. 8) in scenario C

respectively (the dependence of maximum Ah on ETh is non-linear). The markings in Fig. 8

relate the upper and lower charts and are set at An/Ao equaling 1 and 2 respectively.


25

3.3.2 Model 2

Because of the model structure, the response of Ah_max to the proportion of Q exploited in

Model 2 is fully linear. Focusing on the scenario of exhaustive water consumption, however,

Tab. 9 presents Ah_max in Sellas under the different cases and scenarios considered. Again,

simulations in Gianouzagas result in similar results, i.e. the proportions of At feasibly covered

by HYP in the two catchments are similar. In scenario C for example, Ah_max is around 50%

and 60% of At in both catchments in case 1 and 2 respectively.

Generally, in case 2 where only OLV is converted, larger areas of HYP are feasible compared

to case 1 where NV is converted initially. Ah_max in case 1 is 18% smaller than in case 2

through all scenarios A-C in Sellas. It is furthermore clear that ETh has a considerable

influence on Ah_max in both cases. Ah_max in scenario A, for example, is more than 200% of that

in scenario C. Also, Model 2 evidently generates larger areas of HYP feasible than Model 1.

This can be seen by comparing Ah = 19.1 km2 at Ao = 0 to Ah_max = 42.1 km

2 (case 1) and 51.1

km2

(case 2) in scenario C.

Table 9: The results of Model 2 in Sellas, i.e. the largest area of HYP possible (Ah_max, km2 (% of At))

before exceeding P if Q is completely exhausted. Case 1 assumes (all) NV is converted first and case 2

that no NV is used (i.e. only OLV is converted) (A = 900, B = 1075 and C = 1250 mm/yr of ETh).

Case 1 Case 2

A B C A B C

Ah_max, km2(% of At) 92.5 (105) 57.9 (66) 42.1 (48) 113.0 (129) 70.7 (81) 51.1 (59)

Finally, it should be noted that neither case 1 and 2 in Model 2 can be directly translated to

Model 1. The latter corresponds to a case where the “remaining” ET after satisfying ETh (ETt -

ETh) is “distributed” between OLV and NV regardless of their initial areas (only At and Ah are

decisive in Eq. 6). Changes therefore occur in Ao (decrease) and An (increase) simultaneously

and theoretically, Ao is transformed to both Ah and An.

3.4 The interviews and questionnaires This section provides a summary and overview of the narratives, information and opinions

gathered through the interviews and questionnaires. Interpretation and connective reasoning

are found in discussion below.

3.4.1 The questionnaires: Opinions of local actors

Fig. 9 illustrates the statistics generated with the questionnaires. For clarification, the answers

to question (Qn) 3 have been converted (see the box below) to merge with the graph. For

completeness with regard to this question, 20 people answered “decreased”, 3 answered

“unchanged” and another 3 “increased”. The oral and written comments given in connection

to the questionnaires are summarized in Tab. D1.

Karin Ekstedt

26

1. Access to water is important in my daily life/work 2. Water availability limits my daily life/work 3. In recent years, water availability has: increased(10) / been unchanged(5) / decreased(1) 4. I am well informed about rules and regulation regarding the use of water for my daily life/work 5. Water availability may limit my daily life/planned work in the future 6. I am well informed about water management in the region and know how it is handled 7. Water resources are well treated and managed in the region/basin 8. The water policies and management plans are transparent and allow for involvement of local

stakeholders/actors 9. There are no conflicting interests for water use in the region/basin 10. The current water resources are enough to protect the environment and the ecosystems in the region

Figure 9: Graph illustrating the questionnaire statistics and a presentation of the corresponding

questions below. The grey bars indicate the mean of all answers, the triangles show the mean of the

farmers, the asterisks the modes (the most common answers), the intervals indicate standard deviation

(std) and the numbers at the bottom indicate the number of “no opinion/do not know” answers.

There is agreement that water is indeed an important factor (Fig. 9, Qn1) and that many

consider water availability as limiting in their daily activities (Qn2). Furthermore, despite a

larger spread, the majority of those surveyed believe water resources have decreased in recent

years (Qn3) and that availability will become increasingly limiting in future operations (Qn5).

Farmers’ opinion generally follows the overall average yet in Qn5, it deviates towards a

stronger agreement of future restraints compared to average.

Regarding rules and regulations of individual water consumption (Qn4), most who answered

seem to be well informed yet there is a wide spread in replies. For regional water management

there was even greater spread and average is somewhat lower (Qn6). As for the opinion then,

on how water management is run, water resources are not seen as well treated (Qn7) and

transparency in processes and plans is regarded as low (Qn8). Furthermore, the opinion

appears to be that there are indeed conflicting interests around the local water resources,

1 1 3 2 3 4 5 4 0

1

2

3

4

5

6

7

8

9

10

11

12

1 2 3 4 5 6 7 8 9 10

An

swer

(1=

do

no

t ag

ree,

10 =

agr

ee f

ully

)

Question (see box below)

Mean Farmers Mode

no opinion/ do not know


27

though 19% gave no opinion (Qn9). Finally, however, the amount of water currently available

is mostly seen as sufficient for protecting environmental values (Qn10). Still, also here the

opinions diverge; 4 people checked box 1 (water is not sufficient for environmental

protection) and another 4 “do not know”.

3.4.2 The interviews: Narratives of local key actors

Mr. Andrianopoulos and Mr. Crikas: Water management in the municipality of Pylos-Nestor

Water management in the municipality of Pylos-Nestor is accounted for by “ΔΕΥΑ

ΠΥΛΟΥ”: DEYA Pylos (DEYAP). Its board members are assigned, and regulations and

activities are approved for, by the municipality. Apart from facilitating technical water

management it has a responsibility also to regulate public water use and to inform and raise

public awareness regarding water related issues. Local stakeholders are integrated in the

management process by allowing two of the seven seats on the board to one “commercial

representative” and one “local citizen”, respectively. By law, the company must produce and

distribute a yearly booklet accounting for their operation and plans, guidelines for local

citizens and for costs of water use. As for the implementation of the EU WFD there is so far

no regional river basin authority installed in the region. However, the Ministry of

Environment, Energy and Climate Change is gradually gathering data from local authorities

to set up a large-scale plan for implementation. Furthermore, the directive is incorporated in

legislation (N.1069/80) that governs local water management already.

Most drinking water in the region is from subsurface aquifers located inland at higher

altitudes. Water to the areas of Pylos and Gialova (round Gianouzagas and Xerias) is

transferred from the Chandrinou springs while to the areas of Chora and Costa Navarino (the

Sellas catchment) water it is taken from the springs of Kefalovriso near Chora. There are two

additional withdrawals closer to Gialova but because of high salinity - 1500 μS/cm compared

to a maximum allowance within EU of 2500 μS/cm - these are used only rarely.

There are no bigger industries hence the main consumers on the network, approximately in

order of mentioning, are the hotels, restaurants and households. Farmers use separate wells for

irrigation and up till now there has been little control of their number and withdrawal. In 2012

however, all wells were reregistered in accordance with new regulation. New permissions

will be handed out successively from the Peloponnese prefecture and hydrometers will be

installed to control water consumption. In the municipality of Filiatra northwest of Pylos three

to four reservoirs were recently constructed for municipal irrigation supply but no such

solution exist round Pylos.

Waste water treatment is set up in two different systems. The first involves a local treatment

plant in Pylos where water from those connected to the network is treated biologically and

then discharged into the sea outside the village. Restriction levels are set by the Ministry of

Environment and are checked by chemical engineers three times a week. There are about

20 000 residents in the municipality and the system was constructed to cover 16 000 of these.

Currently, less than 20% of the municipality population and about 50% of population in the

village of Pylos are connected. The rest, counted to the second system, collects their waste

Karin Ekstedt

28

water in tanks that are regularly emptied and transported to Kalamata for treatment. There

also exist separate small-scale solutions that mainly discharge into ground water or supply

agriculture with irrigation water and fertilization. The size and oblong shape of the

municipality, together with the scattered layout of small villages and touristic activities, make

it a complex task to connect all households to the local network. Still, there are plans for a

new plant close to Gialova that will cover 60-70% of the population and all in Pylos.

There are issues of seasonal shortages in the area and one of the main issues at these times is

the public’s unawareness of the circumstances. Water is wasted for washing streets and

watering gardens despite temporary restrictions. It usually passes, however, with the

municipality “closing their eyes”. Currently there is no control of the actual flow magnitudes

in the distributing network. DEYAP is therefore planning to install a monitoring system that

will enable real-time measurements, troubleshooting and balancing of in- and outflows. There

are thoughts of trying water pricing to regulate consumption, it has proven successful in

reducing water use in Athens earlier. For increasing and securing water supply there are plans

for withdrawing water from another aquifer at Eleofito near Pylos. The Environmental Impact

Assessment (EIA) has been approved by the prefecture, grants have been given at EU-level

and the pumping stations are now under construction. It will supply the new Costa Navarino

development in Navarino Bay but primarily also Pylos and surrounding villages. This water is

of lower salinity (600 μS/cm) and will substitute for the water pumped at times from Gialova.

To compensate summer shortages further, there are ideas also of desalinization and of

constructing surface water reservoirs similar to those of Costa Navarino (see below). There is

currently no budget for such plans however.

Mr. Boulolis: Local agriculture and water management

Olives dominate agriculture in the area and there are 1000-2000 olive farms and 12 active

agronomists within 10 km of Gargaliani only. Other common crops are grapes, blackcurrant

and vegetables. Grapes and blackcurrant are generally not irrigated but vegetables, such as

tomatoes, cucumbers and peppers, grown in greenhouses consume a considerable amount of

water, as much as 80 tons/day/ha approximately (compared to 20 tons/day/ha in OLV).

The most common technique in olive agriculture is drip irrigation and water is mainly

withdrawn from separate ground water wells. Almost all local wells were constructed before

the 1990’s by groups of farmers joining in cooperatives and sharing the costs. The only

requirement was a license for the construction and electricity and farmers now only pay for

the latter, about 3 Euro per hour, while water is free. In Filiatra farmers pay about 8 Euro per

hour for the water, electricity and service of the municipal supply. The wells are usually 100-

150 m deep but the oldest ones are around 20-30 m and used for drinking water and small-

scale irrigation only. Because there is a set minimum distance between the wells there is

basically no room for new ones in the area. Farmers requiring additional water turn to existing

cooperatives and surplus for access is not uncommon.

Much water has been exploited for irrigation, especially around the 80’s. Water availability

has been considered high and withdrawals have allegedly not affected the aquifers. Boulolis

expresses however, that recent climatic changes have caused higher irrigation demands and


29

less rainfall for ground water recharge. In shallow wells down to 20-30 m, there have been

signs of declining water levels and increasing salinity of up to 2500-2700 μS/cm. Also, there

is an issue of pollution from garbage deposited in the cities contaminating the proximate

aquifers.

In later years nonetheless, there have been attempts to optimize and reduce water

consumption and thereby increase sustainability. In Gargaliani, agronomists and farmers have

been cooperating around education on irrigation and integrated crop management the last ten

years (Fig. 10). In addition, the recent governmental initiative aiming to map out the irrigation

system and regulate water consumption, has required farmers to fill in forms reporting the

location of the wells, use of electricity and the amounts and purpose of irrigation. The

workload for the agronomists has been comprehensive yet it is important for the farmers to

receive the necessary license to continue irrigation.

Figure 10: Farmer (in orange) and

agronomists during a quality system

inspection in a local olive field. Photo

courtesy: Konstantine Boulolis.

Mrs. Zontanou: Ecological farming and water management

Nileas is an emergent corporation in Chora that is gathering farmers for achieving good

quality ecological farming. The organization has two agronomists that offer advice on for

example the use of pesticides and fertilizers and on water management in olive agriculture.

They also help with environmental certification such as for the EU Eco-Management and

Audit Scheme (EMAS) and the Environmental Product Declaration (EPD) (in cooperation

with the Swedish-based secretariat). The corporation now encompasses around 90 producers

and exports organic olive oil produced since 2002 to Austria, Germany, Canada, and the U.S.

and there is a quickly growing interest and market for its services and products.

There is no support for this type of activity from the ministry and related ongoing

governmental programs are very slow. With the upcoming new permission system, Nileas has

assisted its member farmers with controls and paperwork that will provide the information for

new irrigation licenses. With this there will be increased regulation adapted to the local

aquifers yet because olive trees consume little water, farmers rarely exceed restrictions.

Again, there is no general system for common irrigation water supply yet it might be

beneficial to construct a municipal dam for such purposes in the future.

Karin Ekstedt

30

Mr. Karakousis: Costa Navarino and water management

Planning the resort from its initial stage TEMES has had the possibility of incorporating water

management from the start and it has been done with high ambitions of sustainability. At the

very first a thorough and scientific investigation (which has not been reviewed in this study)

was financed to examine the local hydrogeological setting and used by the developers to set

up the resort’s water supply. This survey has also been made available to the municipality and

prefecture to be used in public water management planning. Furthermore, TEMES has

assisted with new mapping and data for the additional wells around Pylos planned in

collaboration with the municipality. The developers also engage in local communities and

environment and did for example contribute financially to hydrological studies in Gialova

lagoon (see below).

Drinking water for the resort is, as given by law, taken from the municipal supply but internal

water saving schemes minimize demands. For golf course irrigation, a separate system has

been developed. In order to evade adding pressure on local aquifers and to maintain

sustainability TEMES built two surface water reservoirs for this purpose. These have a total

capacity of 700 000 m3 and are recharged from the local rivers in the area: Sellas,

Gianouzagas and Xerias. The one at Korifasi supplies the courses at Navarino Dunes and the

one near Pylos (Fig. 11) is used for those at Navarino Bay (Fig. 2). In general, the reservoirs

are exploited during summer with peaking demands in August, and are refilled again during

autumn and winter.

Figure 11: The surface water reservoir constructed by TEMES close to Pylos. Photo: Karin Ekstedt.

The volume of extraction is regulated by a license and controlled by the water authority at the

Peloponnese prefecture. No more than 2% of winter discharge is used for filling the tanks and

an environmental permit at ministerial level verifies that the local river ecosystems will not be

disturbed. The actual irrigation is furthermore optimized via meteorological monitoring

systems and through models connected to automatic sprinkler installations. As a

supplementary source, internal waste water treated by TEMES in their own treatment plant is

also put in use for the golf course irrigation. Finally also, a variety of grass has been planted

that requires less water than would the average types.


31

Mr. Maneas: Gialova lagoon and water management

Regarding Gialova lagoon there is currently no particular plan for its water management. The

area is protected under Natura 2000 and it has become important to the touristic development.

Conservation of the lagoon started in 1998 after two local oil spills in 1992 and 1996

respectively. The EIA brought up the wealth of the ecosystem but also its dystrophic crisis

caused by years of drainage, exploitation, eutrophication and pollution. HOS has been running

the protection programs since, financed through the EU LIFE project, and the wetland is now

classified as an “Important Bird Area”, a “Special Protection Area” and a “Site of Community

Interest”. The municipality also cooperates with HOS in a program called “Conservation and

Awareness”.

In one of the conservation projects in 2000 one managed for example, to reopen two of the

drainage channels to recover the wetland. Attempts have been made also at reducing the

farmers’ water consumption and thereby increasing freshwater recharge, yet these have been

fruitless and levels of salinity are still too high. The study made in cooperation with TEMES

was completed in 2 years and included the collection of for example salinity, oxygen,

temperature, phosphorus and phytoplankton data, and it has resulted in a number of

management directives. There is a need, for example, to have a freshwater reservoir to support

the wetland during the dry season, management needs to shift focus from fishing to

environmental conservation and the area included under the protection needs to be expanded.

The influence of nutrients and pesticides has not yet been fully investigated because of the

costs and thus remains a topic for studying.

4. DISCUSSION The region of Messinia and the area around NEO has seen much human development through

history though in recent decades there has been a long period of undisturbed and highly

developed olive agriculture. 70-90% of the catchment areas are farmland and the system of

farmer cooperatives, associated agronomists and irrigation schemes is well established.

Development is now in an interesting phase where tourism and related business is growing

and it could be a turning point for the level of activity in the area. It is also a point where

policy makers have the opportunity of setting the frame for managing natural resources and

where it is important to keep up with development and have good knowledge about the local

environment. This is particularly true in the light of expected climate change.

These discussion sections make an attempt at putting together and interpreting the results and

at addressing the objectives of this study; at evaluating the current state of water resources,

their capacity of accommodating intensification and finally their management (see study

objectives). First however, follows an account of study performance and uncertainties.

Karin Ekstedt

32

4.1 Performance and uncertainty Naturally there are uncertainties inherent in the data and methods that should be accounted for

in analysis and interpretation of the results. Most data issues were addressed in the data and

method’s section. They include for example extremes and missing values in the raw data

series, lack of Q metadata (location, state of the river bed, rating information etc.), and short

time coverage. Treating such short interval of three years only, impairs the assumption of

constant storage in the water balance. Furthermore, the years may not be representative for the

long term average. Gianouzagas for example, covers only one year, which is the wettest year

of the three. A less simplified model would likely give higher accuracy on such short

temporal scale though it would also demand extensive monitoring and data quality. Given

current data availability the simple annual water balance is likely the most reliable approach.

The resultant average annual rainfall in the local catchments (890 mm) falls well within the

range expected from previous regional studies. It is in the middle of the range 800 to 1000

mm estimated for this area and altitudinal range (Loy and Wright, 1972; Ministry of

Environment, 1997). The small difference between the catchments indicates local variability

is small as expected. Larger yearly ranges however show that rainfall varies interannually and

that these particular years may, again, not be representative of the long-term average.

Because no previous studies have been found, the current estimate of discharge and water

balances cannot be compared to observations in similar catchments. Moreover, the issues in

the discharge data of Gianouzagas and Xerias prevent comparison between the catchments.

There are factors that have not been investigated, such as bedrocks, soil types and geological

structures, which could cause spatial differences. Still, the proximity and climatic and

physical similarities between the catchments allow for assuming, in this study, that the

hydrological regimes are similar. Also, the one year in Gianouzagas (HY3) coincides with and

therefore shows consistency with discharge in Sellas. The hydrographs of the rivers (Fig. 3)

furthermore show that the hydrological regimes are somewhat similar in the catchments,

despite the data issues, and often follow variation in precipitation. There are peaks during

winter in both Sellas and Xerias and a simultaneous maximum peak in all three rivers in

February 2012. It is possible that an extreme rainfall event caused this high flow, which might

have wiped out instrumentation or affected the river bed in Gianouzagas judging from its

sudden dip in later observations. This event is not accounted for in the P-data series however.

Lastly, interannual changes in discharge in Sellas follow annual variation in rainfall as is

expected (Fig. 7).

There is uncertainty inherent also in the estimation of ET in local olive agriculture and native

vegetation. As mentioned, the estimation of land use distribution used for calibration is based

on previous regional mapping that may not capture all potentially important local features and

there are only two land use categories. “Native” vegetation represents a range of land covers

that may be different in their evaporative characteristics. Also, precise estimates of ET (as

those from the literature review) are site specific and can rarely be extrapolated spatially

(Fernández, n.d.). This was accounted for however, through scaling the regional average to

the local conditions (see methods). Furthermore, ET resulting from the local water balances

(averaging 540 mm/yr in Sellas) is in the same range as the regional estimations (730 and 410


33

mm/yr in OLV and NV respectively), even if it is comparatively low considering the high

proportion of OLV in the catchment. Indirectly, through the water balance, it indicates that

also the measured Q is in a realistic range.

The land use change modeling next is of course a highly simplified version of a more

complex, dynamic and non-linear response in reality. Uncertainty in the raw data can

moreover propagate also into this analysis. Nonetheless, the simulation gives a robust

indication of the catchment dynamics. The simplicity of the models is adapted to the limited

data availability and the consistency in the results (with expected responses to i) increasing

ET in the new land use, ii) the type of land use transformed and iii) increasing water

exploitation) shows that physical relations are well simulated.

In the interviews and questionnaires finally, two potential sources of uncertainty are linguistic

misunderstandings and the loss of nuances. Smoother communication of course enables

deeper and more extensive discussion as well as collecting a greater number of interviews and

questionnaire responds. Without explanation the mentioning of “university” and “survey”

became intimidating to many. Having no recording device also limits the exact interpretation

after the meetings. Thorough notes were taken however and the texts have been approved by

each respective interviewee. It is apparent furthermore, judging from disagreement between

related rankings and comments, that the questions in the questionnaire were sometimes

misinterpreted. Thus, any interpretation should be made with care.

4.2 The current state of local water resources

4.2.1 Water availability and demands

Abundant water resources, in a regional context, might very well be one of the reasons for

Messinia’s significance through history, and it has certainly contributed to its prosperous

agriculture. It thus appears there has long been a surplus of water for development in the

region. As Mr. Boulolis expressed in the interview, local water resources are considered

plentiful and much water has been exploited for irrigation so far. As mentioned, rainfall here

is much higher than average in Greece and the annual amounts of 890 mm 2009-2012 can

even be further compared to for example Sweden in northern Europe, where the average

rainfall was 620 mm/yr 1860-2012 (SMHI, 2010). Geology in the local area is favorable for

infiltration and storage which, because of high PET particularly in summer, is indeed

important for water availability in this region and climate. Likewise, the Ministry of

Environment (1997) considered water resources and aquifers in this part of the country as rich

and MEECC (2010) describes its supply as “superfluous” in relation to demands under current

conditions.

Altogether, judging from general distribution in Greece and the large proportion of farmland

in the area, the dominating actor in regional and local water consumption is most likely

agriculture. Olive trees consume relatively little water per unit area compared to other crops

(Boulolis, 2012; Zontanou, 2012) though large areas are farmed and up till now water has

been free and withdrawal from local aquifers nearly uncontrolled. Based on independent

numbers provided by Mr. Boulolis, 100-150 mm (11-17% of annual rainfall 2009-2012) is

Karin Ekstedt

34

used for irrigation annually. Again, this is a rough estimation. It is little in comparison to

literature estimations of 180-403 mm/yr, but then these are estimates for irrigated fields and

not necessarily scaled to the catchment. Scaled to the local catchments and normalized over

the total area the literature numbers indicate an extra 200-220 mm/yr is evaporated from local

olive fields compared to native vegetation. This implies that the estimated 100-150 mm per

year of irrigation allows farmers to compensate (within the margin of error for such a coarse

estimate) for the relative excess water lost through olive fields compared to native vegetation

through re-allocation of groundwater on the land surface. It could also show part of the extra

demand is supplied from precipitation and that relatively little irrigation is required, which is

in line with reputation and previous studies confirming this area’s abundant water resources

as described above (e.g. Loy and Wright, 1972; Ministry of Environment, 1997; Zangger, et

al., 1997; MEECC, 2010).

The municipal water supply network also draws upon local aquifers. The largest demand on

the network is from the local business and tourism industry with its hotels and restaurants

(Andrianopoulos and Crikas, 2012), which is indeed an important feature in Greek economy

(e.g. Cudennec, et al., 2007; MEECC, 2010; García-Ruiz, et al., 2011). On the network is now

also Costa Navarino which, counting demands for golf course irrigation, probably is the main

single actor affecting local water resources. The high ambitions of sustainability in its

development, however, have led to several measures for minimizing its influence

(Karakousis, 2012). Domestic uses make the second largest demand on the network and are

also important in local water consumption.

From the questionnaire survey (Qn9, Fig. 9) it appears that the opinion exists of conflicting

interests in the area. Someone mentioned unjust withdrawals in agriculture and someone

brought up “negotiations” with TEMES that gave an unfavorable outcome for the

municipality and local stakeholders (Tab. D1). Importantly, these are subjective views among

individual citizens. With that, the extension (and projected increase) of agricultural

withdrawal does generally create a risk for conflict and competition for water resources with

other uses in the Mediterranean region (Bosello et al., 2013). This implies it could be an

important issue to consider also in local water management.

4.2.2 Capacity of accommodating hypothetical land use intensification

The hypothetical change considered here, the introduction of a highly evaporative land cover

(HYP), can represent any intensification in land use that raises water consumption, in this case

causing ET to approach PET. Countermeasures in land management for such intensification

could include parallel abandonment of (other) agricultural land or general reductions and

savings in irrigation amounts. In Model 1 this is represented by a simultaneous transformation

of olive fields (OLV) to both HYP and native vegetation (NV). Of course the required

reduction of OLV (savings gained) depends on the type of vegetation established afterwards

and full development may take many years. Here, the farmland is assumed to be left to a mix

of native vegetation and its ET is related to regional literature values. Also, it is not relevant in

reality to assume all OLV and irrigation should be abandoned. When the area of NV equals

that of OLV (An/Ao = 1) or earlier already, results start losing their relevance because of

socioeconomic losses (i.e. if HYP is not simply intensification in agriculture).


35

From the three considered scenarios in Sellas, it was found that the area for growing olives

(Ao) must be reduced by 2.1-3.4 units for each unit increase of hypothetical land use, in order

to keep the water balance of Sellas as it is today. This means that at an area of 10 km2, already

up to 34 km2 of current OLV would be lost. Also, assuming all olive agricultural water

consumption is stopped (Ao = 0), as little as 22% (19.1 km2) of the total area can be covered

by HYP in Sellas (if its ET is close to the potential). Thus, intensifying the land use in the area

to this extent is difficult without affecting the current water balance. This is likely because of

the high PET that causes vegetation to consume much water if provided. It is clear in the

model accordingly that impacts depend greatly on the ET of the new land use, particularly the

larger the development (compare the scenarios of increasing ET). Numerous studies point

accordingly to the decisive influence of ET on water resources during land use changes

(Brown, et al., 2005).This implies not only the area transformed, but also the land and water

management applied, are important. Timing and type of irrigation as well as type of

vegetation might influence capacity for example. The approach aimed for by TEMES, using

meteorologically controlled irrigation systems and low-evaporative grass types for their golf

courses (which create intensification in land use), is seemingly an effective method for

reducing the hydrological impacts.

Increasing the total water consumption above today’s level, i.e. exploiting a higher proportion

of discharge, naturally allows for considerably larger areas to be covered with HYP (Model 2).

Of course a complete exhaustion of the water resources for irrigation is not realistic - there are

competing interests for example for human and ecological needs, supply and demands are

seasonally unbalanced and not all water is exploitable for technical, economical or quality-

related reasons - yet it demonstrates what extents are theoretically possible. Whether OLV or

NV is transformed to HYP is a matter of the specific situation. OLV normally covers more

attractive and accessible land for development plus abandonment results in water savings

(compare case 1 and 2). Exploiting NV however, prevents the loss of fertile farmland.

At this scale, evapotranspiration of the new land cover has substantial influence. In scenario C

(ETh is 1250 mm/yr which correspond to PET) no more than 59% of the total area is possible

while in scenario A (ETh is 900 mm/yr) already the entire catchment can be exploited; with a

surplus of water (P now exceeds ETh). Thus, if evapotranspiration (again) is kept low,

increased water withdrawals could enable substantial intensification while still satisfying

other water requirements in the area (i.e. if feasible and desired in land use management).

Also, considering the current levels of consumption this implies there is a present (annual)

surplus of water available for development (inherent in Q). This is only true however, if the

excess water is accessible and if other demands are small and satisfied. It is unclear how

much of the “excess outflow” in the rivers that can be further exploited considering the

reservoirs already constructed by TEMES. Also, it would require additional infrastructure for

storage because of the uneven seasonal supply. It has been shown that reservoirs affect river

systems considerably and that functioning is sensitive to hydrological alterations brought for

example by climate change (García-Ruiz, et al., 2011), which could be notable in the region

(e.g. IPCC, 2007b; MEECC, 2010; Trondalen, 2009). All in all this implies there is theoretical

Karin Ekstedt

36

capacity for increased water consumption and land use intensification in the local area but

then it may not, necessarily, be achievable in reality.

4.2.3 Is there shortage or surplus of water resources and are current levels of consumption

sustainable?

If there is shortage or surplus of water depends on the balance between supply and demand.

As described above local water resources in the area are considered (and are) comparatively

rich and there is considerable surface outflow from the basins at today’s level of consumption.

Thus, there should be a surplus of water in the local area. On the other hand, Mediterranean

water resources are bound by climatic seasonality. Not only is annual PET high (compare

1240 mm to 200-600 mm in Sweden 1961-1990 (SMHI, 2009)) but as it peaks during

summer, there is essentially no rainfall. At the same time, agriculture and tourism are two of

three main local consumers of water, and their demands are greatest during the high summer

season. This suggests, as is typical in coastal regions around the Mediterranean (e.g.

Cudennec, et al., 2007; Giorgi and Lionello, 2008; MEECC, 2010; García-Ruiz, et al., 2011),

that there is a seasonal imbalance in supply and demand - which brings an apparent shortage

of local water resources during the summer season. This matter is also confirmed by the

managers at DEYAP and in several questionnaire comments (Tab. D1) where many point

specifically to summer deficiencies. Answers to Qn2 also show that water availability

commonly is a limiting factor in every-day operation of local stakeholders.

Storage in the aquifers allows for winter excess to be extracted during the dry summer season

and this, again, is what enables extensive agriculture. As it is, irrigation withdrawals go far

back in time and agriculture is now close to its maximum extent judging from its domination

in the catchments. The question is then if supplies and demands are balanced in the long-term

and if consumption is sustainable. That might very well be the case considering the annual

surplus addressed above, and the opinion seems to be that exploitation has not yet affected the

reservoirs. Still, there appears to be signs (see interview with Mr. Boulolis) of declining

ground water tables as well as deteriorating quality with both pollution and increasing salinity

in shallow wells (not scientifically confirmed). In the old wells near Gialova, salinity is

almost too high to pump for drinking water and in the questionnaire (Qn3), majority of those

surveyed feel water availability has decreased in recent years.

Thus, based on unofficial sources it appears local ground water resources are experiencing

(increasing) pressure. Whether this is because of over-exploitation or a result of climatic

variability or change is difficult to judge but it may point to a state of non-sustainability.

Several studies stress the sensitivity of coastal aquifers in the Mediterranean region, the over-

exploitation, the lowering of ground water tables and increasing risk of salt water intrusion

(e.g. Cudennec, et al., 2007; MEECC, 2010; García-Ruiz, et al., 2011; Mazi, et al., 2013).

This implies that the issue of sustainability requires attention in both research and

management, even if more extensive studies and monitoring are required to objectively

determine the actual state in the local catchments.


37

4.3 Local water management The setup of water management in the municipality of Pylos-Nestor was described through

the interview with Andrianopoulos and Crikas (2012). Since the municipal population

exceeds 10 000 the management is arranged through a DEYA as is common in Greece and its

main challenge is apparently also similar to what is typical in the country: the balancing of

increasing socioeconomic development with a risk of decreasing water availability. Here

follows an evaluation of water management in the local area, based on literature and on

findings in the study.

There are several strategies for adapting to increasing water stress, comprising both supply

and demand side measures. Supply-side measures include water recycling and consideration

of alternative sources (e.g. Safarikas, et al., 2006; IPCC, 2007b; García-Ruiz, et al., 2011;

Bosello, et al., 2013). In the local area this could correspond to building extra surface water

reservoirs for irrigation in order to redistribute pressure from local aquifers. This has been

done by TEMES and is considered by DEYAP together with ideas of desalinization. Based on

previous reasoning there is capacity for increased withdrawals still it may not be

straightforward in practice. It could also mean exploring other locations for ground water

exploitation, as is already underway. DEYAP is working on improving the drinking water

supply and waste water treatment which is important for securing human requirements. As

mentioned however, the issue of aquifer sustainability must be considered in such

development.

Demand-side measures include reduction of leakages, water conservation and water prizing

(e.g. Safarikas, et al., 2006; IPCC, 2007b; García-Ruiz, et al., 2011; Bosello, et al., 2013).

Degraded networks are a common issue in Greece overall (Tsagarakis, et al., 2003) and local

voices claim it is indeed an issue in the study area (Tab. D1). Thus, this might be an issue to

address in local management. It is common in Greece also that water prices are set too low.

Tariffs are often in conflict with the business sector and domestic expenses, and they are

usually set merely to cover the running costs of the DEYA (Safarikas, et al., 2006). In this

context the strong institutional framework is important to set clear guidelines and distribute

responsibility (García-Ruiz, et al., 2011; Bosello, et al., 2013).According to Mr.

Andrianopoulos and Mr. Crikas water pricing is one of the strategies considered at DEYAP to

prevent water over-consumption and deductions in this study imply this is indeed an

important tool and measure.

There are some contrasting views on the degree of integration of local stakeholders in the

management processes of DEYAP. The commercial sector and local citizens are represented

in the board of DEYAP, planning and actions are accounted for in yearly information

distributed to the households and there is seemingly dialog and cooperation with the

important actor of TEMES. Most of those asked in the questionnaire accordingly seem well

informed about regulation (Qn4) and more than half feel they have insight in regional water

management (Qn6). When it comes to the possibility of local stakeholders and actors to

participate and become involved in the process however, responds are negative (Qn8) and

answers to Qn7 show that confidence in local management is low. The work and influence of

the board representatives mentioned have not been investigated in this study yet, based on

Karin Ekstedt

38

motivation in previous studies (e.g. Tsagarakis, et al., 2004; Bosello, et al., 2013), it could be

that both managers and stakeholders could benefit from greater outreach and a more open and

integrative process. This would be the goal while implementing the EU WFD also.

As was described in the introduction the main responsibility for strategic environmental

planning is on national and regional (prefectural) levels yet DEYAP governs local

implementation. According to Mr. Andrianopoulos and Mr. Crikas much attention is given to

environmental needs, for example through supporting preservation work in Gialova lagoon.

There are evident issues remaining in management of this wetland however (Maneas, 2012;

HOS, 2013). Impression is there is little consideration and efforts made in agriculture and that

there is only limited control of, for example, the influence of freshwater withdrawals,

pesticides and nutrients both here and in the overall aquifers. Most of those asked in the

questionnaire survey believe water resources are sufficient to protect environmental values

(Qn10) yet there are critical voices particularly aimed at unsatisfactory management rather

than limited water quantities. Thus, based on personal communication, there might be a need

for increased environmental consideration in water management and naturally, upstream

measures are equally important as site specific remediation.

Water management in agriculture is particularly important considering its socioeconomic

importance but also its possible influence on local water resources. Future trends are difficult

to predict and will depend greatly on external factors (Nainggolan, et al., 2012). It could be

that stable or growing markets continue to cause intensification in farming or that decreasing

water availability causes water prices to escalate, rendering OLV non-profitable. OLV could

also be gradually transformed in favor of other crops having different water demands and/or

better commodity prices. Given the profound establishment and culture of olive farming in the

region however it will likely remain dominant. Regardless, there is a justified need to control

withdrawals, both for preserving the aquifers and for securing long-term access to water.

Deduced from Qn5 in the questionnaire, farmers are more concerned than average citizens

regarding future water limitation and even more than regarding current limitation in Qn2

(though these difference are small). Closer regulation at prefectural level is clearly in progress

and local farmers are apparently working additionally with agronomists to improve water

management. Markets for ecological farming are furthermore growing judging from emergent

interest of the services and products of companies such as Nileas.

In the end, even if local water resources are currently considered “superfluous”, short-term

unsustainability in ground water exploitation is a common issue in the Mediterranean and

Greece. Indeed, given the projected shift in the balance of supply and demand, MEECC

(2010) has predicted a reduction of also this area’s water surplus. Current management may

be critical for long-term sustainability and future trend predictions should be considered also

here, despite large uncertainty. After all though, it appears local water resources are being

actively and increasingly cared for and management has the potential of being sufficient to

address increasing anthropogenic and climatic pressure given that i) necessary measures are

taken to keep up with development and prevent over-exploitation, ii) environmental values

are sufficiently administered iii) agricultural water consumption is controlled and iv) local

stakeholders and citizens are involved and active in programs for preserving water resources.


39

4.4 Further studies There are several studies that highlight the importance of extensive research regarding future

water supplies, at the local as well as sub-continental scale (e.g. Cudennec, et al., 2007;

Giorgi and Lionello, 2008; García-Ruiz, et al., 2011; Bosello, et al., 2013). Often pointed out,

research should be coordinated in interdisciplinary teams with much cooperation among

scientists and knowledge should be communicated to stakeholders and policy makers. With

the establishment of NEO, policy makers in Pylos-Nestor now have a unique opportunity of

taking advantage of local research and adjusting environmental management strategies. To

enable studies however, it is crucial there is sufficient monitoring and data available. This is

probably the most common key point in the studies mentioned, and perhaps the most

important outcome of this study. To enable local hydrological studies there is a strong need of

improving data quality and exchange, particularly of discharge gauged in the local rivers.

Researchers need more control of the measurements and uncertainty needs to be minimized.

Thus, better communication and exchange between NEO and TEMES, who are conducting

the measurements, should be sought.

Based on issues identified in this study some topics could be suggested for further research.

For example, more detailed mapping of local land use distribution could enable more precise

hydrological modeling. Focus could naturally also fall on investigating future scenarios of

both anthropogenic and climatic changes in the local area, and their influence on local water

resources. Long-term trends in water tables could be evaluated for investigating sustainability

and finally, further study could assess the water quality impacts of pesticides and nutrients

used in local agriculture. Freshwater availability is indeed important in the daily life of local

stakeholders and actors active in the catchments of Sellas, Gianouzagas and Xerias (Qn1). It

is, hence, of importance for proper management and for continuous monitoring and research.

Karin Ekstedt

40

5. SUMMARY AND CONCLUSIONS Summarizing the current state of local water resources it can be concluded that, in a regional

context, they are indeed comparatively rich. Rainfall is higher than average in Greece, there is

considerable outflow from the basins and geology is favorable for ground water recharge.

This has allowed for extensive agriculture and rich nature, which is now also attracting

considerable tourism and possibly other socioeconomic development. On an annual basis

there is a net surplus of water in the local area. Still, considering the temporal imbalance of

supply and demand - especially with agriculture and tourism being the principal water users -

there are seasonal shortages that based on this study do affect local actors.

Furthermore, because of high annual potential evapotranspiration, the water system is

sensitive to intensification in land use. Modeling shows that unconsidered water consumption

requires large countermeasures not to affect the water balance but also that proper

management, keeping evapotranspiration down, may render large capacity of intensification if

withdrawals are increased. The question is however, if such development is feasible in the

perspective of i) accessibility, ii) human and ecological needs and iii) sustainability. There are

signs showing the current situation could be non-sustainable already - either because of over-

exploitation or climatic factors. Reliable conclusions on the subject however, call for more

detailed studies and monitoring. Regardless, any development requires careful management

especially in the light of increasing climatic water stress.

The municipal water management in the area appears to be well established and there are

several measures planned and considered for improving water security at DEYAP. All in all

there is potential for accommodating increasing anthropogenic and climatic pressure given

sufficient measures are taken. Such identified in this study include increasing integration of

local stakeholders, maintaining environmental values and controlling agricultural water

consumption. Also, studying and understanding the hydrological system is fundamental - and

adequate monitoring and data availability crucial. Therefore, as a main implication of this

study, there is a need for data improvements, especially in terms of discharge. In the end,

freshwater availability is, irrespectively and decisively, integral to all ecosystems and to all

aspects in human societies.


41

REFERENCES *Anderson, R.G., Jin, Y. and Goulden, M.L., 2012. Assessing regional evapotranspiration and water

balance across a Mediterranean montane climate gradient. Africulture and forest Meteorology,

166(-), pp.10-22.

*Avila, A. and Roda, F., 1990.Water budget of a broadleaved sclerophyllous forested catchment.

Proceedings and Information - Committee for Hydrological Research TNO, [online] 44(-).

Abstract only. Available at: http://www.scopus.com/record/display.url?eid=2-s2.0-

0025626133&origin=inward&txGid=3F010F9E8408302A6CB54A4DAAEB097E.iqs8TDG0W

y6BURhzD3nFA%3a2 [Accessed 20 November 2012].

AQUASTAT, 2013. Country fact sheet: Greece. [pdf] Rome: FAO. Available at:

http://www.fao.org/nr/ water/aquastat/data/factsheets/aquastat_fact_sheet_grc_en.pdf [Accessed

14 January 2013].

*Baldocchi, D.D. and Xu, L., 2007. What limits evaporation from Mediterranean oak woodlands - The

supply of moisture in the soil, physiological control by plants or the demand by the atmosphere?

Advances in Water Resources, 30(10), pp.2113-2122.

*Baldocchi, D.D., Xu, L. and Kiang, N., 2004. How plant functional-type, weather, seasonal drought,

and soil physical properties alter water and energy fluxes of an oak-grass savanna and an annual

grassland. Agricultural and Forest Meteorology, 123(1-2), pp.13-39.

Baltas, E.A., 2008. Climatic conditions and availability of water resources in Greece. Water Resources

Development, 24(4), pp.635-649.

Beede, R.H. and Goldhamer, D.A., 1994. Olive irrigation management. In: L. Ferguson, G.S. Sibbett

and G.C. Martin, eds.2004?. Olive Production Manual. Berkeley: University of California

Publication 3353, pp.61-68. In: Iniesta, et al., 2009.

Bhattarai, G., Srivastava, P., Marzen, L., Hite, D. and Hatch, U., 2008. Assessment of Economic and

Water Quality Impacts of Land Use Change Using a Simple Bioeconomic Model.

Environmental Management, 42(1), pp.122-131.

Bosch, J.M. and Hewlett, J.D., 1982. A review of catchment experiments to determine the effect of

vegetation changes on water yield and evapotranspiration. Journal of Hydrology, 55(1-4),

pp.03-23.

Bosello, F., Lamaddalena, N., Osberghaus, D. and Ortega C.V., 2013. Perspectives in Resource

Management and Climate Change Adaptation in the Southern and Eastern Mediterranean:

MEDPRO Policy Papers No.6. Brussels: Centre for European Policy Studies (CEPS), European

Commission.

Brown, A.E., Zhang, L., McMahon, T.A., Western, A.W. and Vertessy, R.A., 2005. A review of

paired catchment studies for determining changes in water yield resulting from alterations in

vegetation. Journal of Hydrology, 310(1-4), pp.28-61.

Cudennec, C., Leduc, C. and Koutsoyiannis, D., 2007. Dryland hydrology in Mediterranean regions -

a review. Hydrological Sciences Journal, 52(6), pp.1077-1087.

*David, T.S., Ferreira, M.I., Cohen, S., Pereira, J.S. and David, J.S., 2004. Constraints on transpiration

from an evergreen oak tree in southern Portugal. Agricultural and Forest Meteorology, 11(3-4),

pp.193-205.

Delrue, J. (unpubl. data). [Digital Elevation Model] Contact: Ingmar Borgström, Department of

Physical Geography and Quaternary Geology, Stockholm University. Mail:

[email protected], phone: 08-164810.

*Dettori, S., 1987. Estimación con los métodos de la FAO de las necesidades de riego de los cultivos

de aceitunas de mesa de Cerdeña. Olivae, 17(-), pp.30-35. In: Fernández, n.d..

Karin Ekstedt

42

Diffenbaugh, N.S., Pal, J.S., Giorgi, F. and Gao, X., 2007. Heat stress intensification in the

Mediterranean climate change hotspot. Geophysical Research Letters, 34(11), L11706.

ELSTAT, Hellenic Statistical Authority, 2012. Announcement of the results of the 2011 Population

Census for the Resident Population. [press release] Available at:

http://www.statistics.gr/portal/page/portal/ESYE/BUCKET/A1602/PressReleases/A1602_SAM

01_DT_DC_00_2011_02_F_EN.pdf [Accessed 8 April 2013].

FAO, Food and Agriculture Organization of the UN, 2011. Climate change, water and food security:

FAO Water Report No. 36. [pdf] Available at:

http://www.fao.org/docrep/014/i2096e/i2096e.pdf [Accessed 11 April 2013].

FAOSTAT, 2011. Food and agricultural commodities production: Countries by commodity. [online]

Available at: http://faostat.fao.org/site/339/default.aspx [Accessed 14 January, 2013].

*Fereres, E., 1995. El riego del olivar. Proceedings of the VII Simposio Científico-Técnico

Expoliva’95, p.18. In: Fernández, n.d..

*Fernández, J.E., n.d.. Irrigation management in Olive. [pdf] IrriQual. Available at:

http://www.irriqual.com/Documentos/Fern%C3%A1ndez%20OLIVE.pdf [Accessed 23

November 2013].

*Fernández, J.E., Díaz-Espejo, A., Infante, J.M., Durán, P., Palomo, M.J., Chamorro, V., Girón, I.F.

and Villagarcía, L., 2006. Water relations and gas exchange in olive trees under regulated

deficit irrigation and partial rootzone drying. Plant and Soil, 284(1-2), pp.273-291.

*Fernández, J.E., Díaz-Espejo, A., Palomo, M.J., Girón, I.F. and Moreno, F., 1998. Riego y

fertilización del olivar en la comarca de El Aljarafe (Sevilla). Broucher 32. In: Fernández, n.d..

Finne, M., Holmgren, K., Sundqvist, H.S., Weiberg, E. and Lindblom, M., 2011. Climate in eastern

Mediterranean, and adjacent regions, during the past 6000 years - A review. Journal of

Archaeological Science, 38(12), pp.3153-3173.

García-Ruiz, J.M., Lópes-Moreno, J.I., Vicente-Serrano, S.M., Lasanta-Martínez, T. and Beguería, S.,

2011. Mediterranean water resources in a global change scenario. Earth-Science Reviews,

105(3-4), pp.121-139.

Giorgi, F., 2006. Climate change hot-spots. Geophysical Research Letters, 33(8), L08707.

Giorgi, F. and Lionello, P., 2008. Climate change projections for the Mediterranean region. Global

and Planetary Change, 63(2-3), pp.90-104.

*Goulden, M.L., 1996. Carbon assimilation and water-use efficiency by neighboring Mediterranean-

climate oaks that differ in water access. Tree Physiology, 16(4), pp.417-424.

*Goulden, M.L., Anderson, R.G., Bales, R.C., Kelly, A.E., Meadows, M. and Winston, G.C., 2012.

Evapotranspiration along an elevation gradient in California’s Sierra Nevada. Journal of

Geophysical Research, 117(G3), [online] Available at:

http://onlinelibrary.wiley.com.ezp.sub.su.se/doi/10.1029/2012JG002027/pdf [Accessed 17

November 2012].

HNMS, Hellenic National Meteorological Service, 2013. The climate of Greece. [online] Available at:

http://www.hnms.gr/hnms/english/climatology/climatology_html [Accessed 22 February 2013].

HOS, Hellenic Ornithological Society, 2013. Gr119 Divari Pilou lagoon (Gialova). [online] Available

at: http://ornithologiki.gr/page_iba.php?aID=119&loc=en [Accessed 8 April 2013].

*Infante, J.M., Domingo, F., Fernández Alés, R., Joffre, R. and Rambal, S., 2003.Quercus ilex

transpiration as affected by a prolonged drought period. Biologia Plantarum, 46(1), pp.49-55.

http://www.irriqual.com/Documentos/Fern%C3%A1ndez%20OLIVE.pdf


43

Iniesta, F., Testi, L., Orgaz, F. and Villalobos, F.J., 2009. The effects of regulated and continuous

deficit irrigation on the water use, growth and yield of olive trees. European Journal of

Agronomy, 30(4), pp.258-265.

IPCC, 2007a. Contribution of Working Group I to the Fourth Assessment Report of the

Intergovernmental Panel on Climate Change, 2007. S. Solomon, D. Qin, M. Manning, Z. Chen,

M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller, eds. Cambridge, United Kingdom and

New York, NY, USA: Cambridge University Press.

IPCC, 2007b. Contribution of Working Group II to the Fourth Assessment Report of the

Intergovernmental Panel on Climate Change, 2007. M.L. Parry, O.F. Canziani, J.P. Palutikof,

P.J. van der Linden and C.E. Hanson, eds. Cambridge: Cambridge University Press, UK and

New York, US.

*Joffre, R. and Rambal, S., 1993. How tree cover influence the water balance of Mediterranean

Rangelands. Ecological Society of America, 74(2), pp.570-582.

Kerkides, P., Michalopoulou, H., Papaioannou, G. and Pollatou, R., 1996. Water balance estimates

over Greece. Agricultural Water Management, 32(1), pp.85-104.

Klein, J., (unpubl.). Water resource sensitivity from a Mediterranean perspective - Using a

hydrological model to explore the combined impact of climate and land-water management

changes. MSc. Stockholm University.

Kostopoulou, E. and Jones, P.D., 2005. Assessment of climate extremes in the Eastern Mediterranean.

Meteorology and Atmospheric Physics, 89(1-4), pp.69-85.

*Krishnan, P., Meyers, T.P., Scott, R.L., Kennedy, L. and Heuer, M., 2011. Energy exchange and

evapotranspiration over two temperate semi-arid grasslands in North America. Agricultural and

Forest Meteorology, 153(SI), pp.31-44.

*Lewis, D., Singer, M.J., Dahlgren, R.A. and Tate, K.W., 2000. Hydrology in a California oak

woodland watershed: a 17-year study. Journal of Hydrology, 240(1-2), pp.106-117.

Loy, W.G. and Wright, H.E., 1972. The physical setting. In: W.A. McDonald and G.R. Rapp, eds.

1972. The Minnesota Messinia Expedition: reconstructing a Bronze Age regional environment.

Minneapolis: University of Minnesota Press. Ch.3, pp.36-46.

Lundholm, G., Borgström, I. and Kleman, J., 2009. Land cover of Messinia, Greece. [GIS shape file]

Stockholm University, Dept. of Physical Geography and Quaternary Geology and Navarino

Environmental Observatory.

*Luo, H., Oechel, W.C., Hastings, S.J., Zulueta, R., Qian, Y. and Kwon, H., 2007. Mature semiarid

chaparral ecosystems can be a significant sink for atmospheric carbon dioxide. Global Change

Biology, 13(2), pp.386-396.

Mavromatis, T. and Stathis, D., 2011. Response of the water balance in Greece to temperature and

precipitation trends. Theoretical and Applied Climatology, 104(1-2), pp.13-24.

Mazi, K., Koussis, A.D., and Destouni, G., 2013. Tipping points for seawater intrusion in coastal

aquifers under rising sea level. Environmental Research Letters, 8(1), L014001.

McDonald, W.A. and Rapp, G.R. eds., 1972. The Minnesota Messinia Expedition: reconstructing a

Bronze Age regional environment. Minneapolis: University of Minnesota Press.

MEECC, Ministry of Environment, Energy and Climate Change, 2009. Water resources. [online]

Available at: http://www.ypeka.gr/Default.aspx?tabid=247&locale [Accessed 4 may 2013].

MEECC, 2010. 5th National communication to the United Ntions Framework convention on climate

change. [pdf] Available at: http://unfccc.int/resource/docs/natc/grc_nc5.pdf [Accessed 7

february 2013].

Karin Ekstedt

44

Metzidakis, A., Martinez-Vilela, A., Nieto, G.C. and Basso, B., 2008. Intensive olive orchards on

sloping land: Good water and pest management are essential. Journal of Environmental

Management, 89(2), pp.120-128.

Ministry of Development, 1997. Study for the Water Resources Management in Greece. Athens:

Ministry of Development. In: Baltas, 2008.

Nainggolan, D., de Vente, J., Boix-Fayos, C., Termansen, M., Hubacek, K. and Reed, M.S., 2012.

Afforestation, agricultural abandonment and intensification: Competing trajectories in semi-arid

Mediterranean agro-ecosystems. Agriculture, Ecosystems and Environment, 159(-), pp.90-104.

Newman, B.D., Campbell, A.R. and Wilcox, B.P., 1998. Lateral subsurface flow pathways in a

semiarid ponderosa pine hillslope. Water Resources Research, 34(12), pp.3485-3496.

Newman, B.D., Vivoni, E.R. and Groffman, A.R., 2006. Surface water-groundwater interactions in

semiarid drainages of the American southwest. Hydrological Processes, 20(15), pp.3371-3394.

NTUA, National Technical University of Athens, 2007. National Programme for Water Resources

Management and Preservation. [online] Available at: http://www.itia.ntua.gr/e/docinfo/782/

[Access date unspec.]. In: Cudennec, et al., 2007.

*Orgaz, F. and Fereres, E., 2004. Riego. In: D. Barranco, R. Fernández-Escobar and L. Rallo, eds.

2009. El Cultivo del Olivo, 4th edition. Coedición Junta de Andalucía y Ediciones Mundi-

Prensa, pp.285-306. In: Fernández, n.d..

*Orgaz, F., Pastor, M., 2005. Fertirrigación del olivo. Programación de riegos. In: C. Cadahía, ed.

2005. Fertirrigación. Cultivos Hortícolas, Frutales y Ornamentales. Ediciones Mundi-Prensa,

S.A. Madrid, pp.496-533. In: Fernández, n.d..

*Orgaz, F., Testi, L., Villalobos, F.J. and Fereres, E., 2006. Water requirements of olive orchards-II:

determination of crop coefficients for irrigation scheduling. Irrigation Science, 24(2), pp.77-84.

*Palomo, M.J., Moreno, F., Fernández, J.E., Díaz-Espejo, A. and Girón, I.F., 2002. Determining water

consumption in olive orchards using the water balance approach. Agricultural Water

Management , 55(1), pp.15-35.

*Pastor, M, ed. 2005. Cultivo del olivo con riego localizado. Junta de Andalucía y Ediciones Mundi-

Prensa, 783 pp plus CD, ISBN 84-8476-229-7. In: Fernández, n.d..

*Ryu, Y., Baldocchi, D.D., Ma, S., and Hehn, T., 2008. Interannual variability of evapotranspiration

and energy exchange over an annual grassland in California. Journal of Geophysical Research,

113(D9).

Safarikas, N., Paranychianakis, N.V., Kotselidou, O. and Angelakis, A.N., 2006. Drinking water

policy in the frame of the Directive 2000/60/EC with emphasis on drinking water prices. Water

Science and Technology, 5(6), pp.243-250.

Sánchez-Canales, M., López Benito, A., Passuello, A., Terrado, M., Ziv, G., Acuña, V., Schumacher,

M. and Elorza, F.J., 2012. Sensitivity analysis of ecosystem service valuation in a

Mediterranean watershed. Science of the Total Environment, 440(SI), pp.140-153.

Senay, G.B, Leake, S., Nagler, P.L., Artan, G., Dickinson, J., Cordova, J.T. and Glenn, E.P., 2011.

Estimating basin scale evapotranspiration (ET) by water balance and remote sensing methods.

Hydrological Processes, 25(26), pp.4037-4049.

SMHI, Swedish Meteorological and Hydrological Institute, 2009. Årlig potentiell avdunstning

medelvärde 1961-1990. [online] Available at: http://www.smhi.se/klimatdata/hydrologi/

vattenstand/ arlig-potentiell-avdunstning-medelvarde-1961-1990-1.4098 [Accessed 20 May

2013].

SMHI, 2010. Klimatindikator - Nederbörd. [online] Available at: http://www.smhi.se/klimatdata/

meteorologi/nederbord/1.2887 [Accessed 14 May 2013].

Sofios, S., Arabatzis, G. and Baltas, E., 2007. Policy for management of water resources in Greece.

Environmentalist, 28(-), pp.185-194. In: Baltas, 2008.


45

TEMES S.A., 2009a. Home to more than 271 bird species. [online] Available at:

http://www.costanavarino.com/#/discover/the-gialova-lagoon [Accessed 03 May 2013].

TEMES S.A., 2009b. Sustainability. [online] Available at:

http://www.costanavarino.com/#/sustainability [Accessed 20 February 2013].

*Testi, L., Villalobos, F.J., Orgaz, F. and Fereres, E., 2006. Water requirements of olive orchards: I

simulation of daily evapotranspiration for scenario analysis. Irrigation Science, 24(2), pp.69-76.

*Tirone, G., Dore, S., Matteucci, G., Greco, S. and Valentini, R., 2003. Evergreen Mediterranean

forests: Carbon and water fluxes, balances, ecological and ecophysiological determinants. In: R.

Valentini, ed. 2003, Fluxes of carbon, water and energy of European forests. Berlin: Springer-

Verlag, pp.125-149. In: Baldocchi and Xu, 2007.

*Tognetti, R., d'Andria, R., Lavini, A. and Morelli, G., 2006. The effect of deficit irrigation on crop

yield and vegetative development of Olea europaea L. (cultivars Frantoio and Leccino).

European Journal of Agronomy, 25(4), pp.356-364.

Trondalen, J.M., 2009. Climate changes, water security and possible remedies for the Middle East.

The United Nations World Water Assesment Programme. Paris: UNESCO.

Tsagarakis, K.P., Paranychianakis, N.V. and Angelakis, A.N., 2003. Greece. In: S. Mohajeri, B.

Knothe, D-N. Lamothe and J-A. Faby, eds. 2003. European water management between

regulation and competition: Aqualibrium Project, European Commission. [pdf] Available at:

http://www.wise-rtd.info/sites/default/files/d-2008-07-14-Aqualibrium.pdf [Accessed 4 May

2013].

*Villalobos, F.J., Orgaz, F., Testi, L. and Fereres, E., 2000. Measurement and modeling of

evapotranspiration of olive (Olea europaea L.) orchards. European Journal of Agronomy, 13(2-

3), pp.155-163.

Zangger, E., Timpson, M.E., Yazvenko, S.B., Kuhnke, F., Knauss, J., 1997. The Pylos Regional

Archaeological Project: Part II: Landscape Evolution and Site Preservation. Hesperia, 66(4),

pp.549-641.

*Included in the literature review for finding regional values of ET in OLV and NV (see Tab. A1).

Karin Ekstedt

46

a.

Oliv

e agricu

lture (O

LV

)

A

uth

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nd

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r L

oca

tion

M

ethod

S

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PE

T

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Fern

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pain

F

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286

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45

605

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1983

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2

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55

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648

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Detto

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-

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- 1

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560

4

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200

620

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99

5

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- -

- 1

400

750

6

Fern

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98

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86

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640

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Palo

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SW

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1996-1

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286

730

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653

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-

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588

9

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4

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Villalo

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1983

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06

S S

pain

M

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1983

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835

15

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1983

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200

55

2

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06

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1983

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200

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06

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1983

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2

400

55

2

13

33

10

87

18

Testi, et al., 2

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6

S S

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1998

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100

59

2

13

33

932

19

Testi, et al., 2

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6

S S

pain

M

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1998

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300

59

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33

10

25

20

Testi, et al., 2

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6

Califo

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1998

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76

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IEWED

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: auth

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and

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. So

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lt from

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uced

or th

e full article w

as not av

ailable. A

num

ber o

f abb

reviatio

ns are u

sed to

simp

lify th

e table:

EC

= ed

dy co

varian

ce measu

remen

ts, RE

FE

B =

Reg

ion

al Evap

orativ

e Fractio

n E

nerg

y B

alance m

ethod, R

S =

remo

te sensin

g, S

= so

uth

ern, S

A =

scenario

analy

sis, SC

= sclero

ph

yllo

us, S

F =

sap flo

w m

easurem

ents, S

td =

standard

dev

iation, S

W =

south

western

. Th

e references are in

clud

ed in

the referen

ce list

of th

e main

repo

rt mark

ed w

ith asterisk

s.


47

§T

ab

le A1

cont.

b.

Nativ

e veg

etatio

n (N

V)

A

uth

or a

nd

yea

r L

oca

tion

M

ethod

S

tud

y p

eriod

V

egeta

tion

typ

e P

P

ET

E

T

1

Krish

nan

, et al., 20

11

Arizo

na

EC

+R

S

2004

-2007

G

rassland

(post-fire)

475

-

29

7

2

Krish

nan

, et al., 20

11

Arizo

na

EC

+ R

S

2004

-2007

G

rassland

(un

burn

ed)

340

-

22

5

3

Ryu

, et al., 20

08

Califo

rnia

EC

2001

-2007

G

rassland

565

9

61

31

9

4

An

derso

n, et al., 2

01

2

Califo

rnia

EC

2007

-2008

O

ak/C

onifer

515

-

43

0

5

An

derso

n, et al., 2

01

2

Califo

rnia

Priestly

-Tay

lor m

odelin

g

2008

-2009

O

ak/C

onifer

322

>

13

00

65

5

6

An

derso

n, et al., 2

01

2

Califo

rnia

RE

FE

B +

RS

2008

-2009

O

ak/C

onifer

322

>

13

00

37

1

7

Go

uld

en, et al., 2

01

2

Califo

rnia

EC

+ R

S

2003

-2011

S

avan

na-e

verg

reen o

ak/p

ine

984

5

54

42

9

8

Bald

occh

i, et al., 20

04

Califo

rnia

EC

2001

-2002

G

rassland

525

5

85

29

5

9

Bald

occh

i, et al., 20

04

Califo

rnia

EC

2001

Oak

/grass

494

8

69

38

1

10

Gould

en, 1

996

Califo

rnia

Can

op

y lev

el and S

F.

1989-1

990

SC

everg

reen trees

449

- 443

11

Go

uld

en, 1

99

6

Califo

rnia

Can

opy lev

el obs +

SF

1989

-1990

S

C ev

ergreen

, large sh

rubs

449

-

57

0

12

Lew

is, et al., 20

00

Califo

rnia

Water b

alance

1981

-1997

O

ak w

oo

dlan

d

708

1

916

36

8

13

Bald

occh

i and

Xu

, 20

07

Califo

rnia

EC

20

03

-2004

O

ak w

oo

dlan

d

558

1

089

35

8

14

Joffre an

d R

amb

al, 199

3

Sp

ain

(site 1)

Water b

alance

1984

-1985

O

ak w

oo

dlan

d

895

-

51

7

15

Joffre an

d R

amb

al, 199

3

Sp

ain

(site 2)

Water b

alance

1984

-1985

O

ak w

oo

dlan

d

797

-

48

4

16

Joffre an

d R

amb

al, 199

3

Sp

ain

(site 3)

Water b

alance

1984

-1985

O

ak w

oo

dlan

d

939

-

55

7

17

Infan

te, et al., 2003

Spain

S

F

1993-1

994

Oak

wo

odlan

d

720

1419

191

18

Tiro

ne, et al., 2

00

3

Italy

EC

-

Oak

woo

dlan

d

- -

43

2

19

Dav

id, et al., 2

00

4

Po

rtugal

SF

1996

-1998

O

ak w

oo

dlan

d

665

1

760

41

4

20

Avila an

d R

oda, 1

99

0

NE

Sp

ain

"Watersh

ed ap

pro

ach"

(6 y

ears) S

C b

road

leaved

8

57

-

41

5

21

Lu

o, et al., 2

00

7

S

Califo

rnia

EC

tow

er 1997

-2003

S

hru

blan

d

349

-

36

1

Av

erag

e

596

1

144

41

0

Std

212

5

11

11

2

*S

ee: Alle

n, R

.G., P

ereira, L.S

., Raes, D

. and

Sm

ith, M

., 199

8. C

rop

evapo

tran

spira

tion

- Gu

idelin

es for co

mp

utin

g cro

p w

ater req

uirem

ents - F

AO

Irriga

tion

an

d d

rain

ag

e pap

er 56

. [pd

f] Ro

me: F

oo

d an

d A

gricu

lture O

rgan

ization o

f the U

nited

Natio

ns (F

AO

). Availab

le at:

http

://ww

w.fao

.org

/do

crep/X

04

90

E/X

049

0E

00

.htm

[Acce

ssed 7

January

20

13

].

Karin Ekstedt

48

APPENDIX B: THE QUESTIONNAIRE

Survey on water resources management

Responsible: Karin Ekstedt (+46 73 402 16 36)

Background information

This survey is part of a master thesis in the program of “Hydrology, Hydrogeology and Water

Resources” at Stockholm University in Sweden. The study objectives are to quantify a basic water

balance and to assess water resources management in the region of Navarino. Individual answers in

the questionnaire will not be published but compiled and presented as statistics and anonymous

statements. Participation is greatly appreciated!

Personal information

Ranking questions

Please rank the following issues on a scale from 1-10 where applicable.

Feel free to comment and explain your answers (Greek is okay)!

Do not

agree Agree fully

1. Access to water is important in my daily life/work

Comment:

2. Water availability limits my daily life/work

Comment:

3. In recent years, water availability has…

Comment:

Name (optional):

Contact info (optional):

Gender: male female

Age:

Home town/district:

Occupation:

1 2 3 4 5 6 7 8 9 10 No opinion /

Do not know

PLEASE TURN OVER

increased been

unchange

d

decreased Do not

know


49

Do not

agree Agree fully

4. I am well informed about rules and regulation regarding the use of water for my daily life/work

Comment:

5. Water availability may limit my daily life/planned work in the future

Comment:

6. I am well informed about water management in the region and know how it is handled

Comment:

7. Water resources are well treated and managed in the region/basin

Comment:

8. The water policies and management plans are transparent and allow for involvement of local

stakeholders/actors

Comment:

9. There are no conflicting interests for water use in the region/basin

Comment:

10. The current water resources are enough to protect the environment and the ecosystems in the

region

Comment:

Thank you for your participation!

Other comments:

1 2 3 4 5 6 7 8 9 10 No opinion /

Do not know

Karin Ekstedt

50

0%

20%

40%

60%

80%

100%

0 5 10 15 20 25

% o

f A

t

Ah (% of At)

APPENDIX C: RESULTS OF MODEL 1 IN GIANOUZAGAS The response of An/Ao to Ah in Gianouzagas simulated in Model 1 is similar to that in Sellas

(Fig. 8). Naturally, Gianouzagas has a different initial ratio of An to Ao compared to Sellas

(from Tab. 1 in Data and Methods; Site description: 26/74 = 0.35 and 11/89 = 0.13

respectively) and it has a somewhat higher rate of decrease in Ao with one unit of Ah. For

example, in scenario C ΔAo/ΔAh = -3.8 in Gianouzagas compared to -3.4 in Sellas. The

difference however, is considered insignificant in this context and comparison and similarity

support the results of Model 1 in Sellas.

Figure C1: 0 < An/Ao < 2 as a function of Ah introduced in the catchment of Sellas under the three ETh

scenarios (A = 900, B = 1075 and C = 1250 mm/yr of ETh) (upper chart) and a stacked area diagram

showing the change in distribution between Ao (white), An (checked) and Ah (black) in scenario C

(lower chart). The same graph for Sellas only, is shown under Results; Hypothetical land use

intensification; Model 1; Fig. 8.

0

0,4

0,8

1,2

1,6

2

0 5 10 15 20 25 30

An/

Ao

Ah (% of At)

A

B

C


51

APPENDIX D: COMMENTS TO THE QUESTIONNAIRS Table D1: Summary of the written and oral (in italics) comments given in connection to the

questionnaire (Qn = question). No names are given in order to maintain anonymity.

Translation from Greek was made by Victoras Plevrakis.

Qn Comment

1

It’s impossible to operate without water, most people don’t know of water importance and for example

do not close tap while shaving/showering

Need it for all things

2

Do not drink from the tap

During dry periods

During summer especially

The water in the summer season is significantly less, summer season decreases, sometimes no water

It makes everything very difficult

Tap water is from ground water, do not drink because pipes are bad, but they do drink in Athens

Do not drink tap water because of salinity, bad taste

Net/pipes are from asbestos, ca. 60-70 years old, degrading, it is 20 km from source to city, people buy

water to drink

Some days there is no water

Some years ago water was periodically turned off to save water

3

Water availability decrease due to less rain and gw withdrawal (illegal)

Waste of water, water not drinkable so they don't care, wash cars + streets, irrigate gardens

Due to limited rainfall and bad management practices

Most probably decreased - does not rain enough

Due to climate change less rains and big irrigation need

Have plenty of resources in Petrochori (village between Romanos and Gialova Lagoon)

4

Everybody must be

Different info from different sources, is not from here (lived here for 3 years), no info by post

Based on studies and working experience (answer: 9)

It is common that people with separate waste water tanks cast off used water down the streets at night

to clean the path and to avoid the high costs of emptying the tanks

5 I wouldn't like that

Water is the life

6

But even the others must be

I am well informed but not certain that everyone does what he says

Government and municipality do not involve locals, no integrated management

No info to local citizens about water management and quality

7

Absolutely not, they make quality tests but still not okay

There can be better water resources management in order to save more and not waste it + can use and

save more water

I totally disagree because too much water is spent without being used

Water management should be updated according to 2000160 EU directive

No they are not

Water management is not god

8 Absolutely not

No information is given to citizens about water management and quality

9

Unfortunately there are a lot: olive groves, ground water for irrigation, nobody pays, everyone help

friends to get more than others

There are, and to be more precise in the case of the large touristic resort “Costa Navarino” the

negotiations that took place didn’t have the optimum outcome for the municipality and the local people

(farmer in Chora)

10

Yes, but they must be administrated as well, have water but not handled properly

No, need more water for basic needs

In my opinion it is a matter of water management and not water quantity

local water resource assessment in messinia, greece643960/fulltext01.pdf · 2013-08-29 · local...

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