1.1.1.WATER RESOURCES Greece has a Mediterranean climate with mild and rainy winters, relatively warm and dry summers and many hours of sunshine almost all year. The coldest months are January and February, with mean minimum temperatures ranging between 5-10°C near the coasts and 0-5°C in mainland areas, and lower values (below freezing) in the northern part of the country. The warm season lasts from April until September. The warmest period is in July and August, with mean maximum temperatures in the range 29-35 C. Precipitation is concentrated in the cold period, with almost no precipitation in the warmest months. The amount of rainfall is approximately halved in the eastern part compared to the western part of the country [HNMS, 2009]. Greece has a long-term average annual precipitation of 652mm/year. The long-term average of annual renewable water resources is 74,250 million m³/year of which 78 per cent are considered internal water resources (57,915 million m³) and around 22 per cent are considered external water resources (16,335 million m³). As at 2009 the total dam (reservoir) capacity was 11,770 million m³. Climate change is said to directly affect weather conditions. Since the end of the 1990s, the temperature in Greece has been increasing, especially during the summer. There is a trend of decreasing precipitation, mainly between 1980 and 2000, with a trend of increasing precipitation over the following years. Extreme weather conditions, including flooding, drought, heat-waves and storms, also occur [NCESD, 2009]. The impacts of climate change may be environmental, economic and social (e.g. biodiversity loss, increased insurance in flood-risk zones, changing holiday patterns). However, in Greece, freshwater issues are related to quantity rather than quality. Greece has an uneven spatial mean annual and seasonal rainfall distribution, resulting in rather small catchment areas, small lakes and relatively small rivers, distributed throughout the country. In addition, the catchments in Greece are marked by high spatial differences in morphologic, climatic, hydrographical, petro-graphic and vegetative features. The hydro-geological conditions differ significantly with geographical latitude and longitude. The main aquifers have been formed either from depositions in layers of sand, gravel and shingle or from chalky rocks that become karst due to the flow of water through cracks that were shaped by tectonic movements. It should be emphasised that groundwater that flows in aquifers of the first category can be utilised more easily and therefore has already been exploited intensively. On the other hand, karst groundwater was not abstracted until 1968 and there is still the possibility of further utilisation. The overabstraction/exploitation of groundwater resources has in many instances led to the decline of the water table as well as to the deterioration of water quality, primarily through saltwater intrusion in coastal areas. There are 14 river basin districts in Greece. In the north there are the Thrace, the Eastern, Central and Western Macedonia, and the Epirus. In the central part of the country there are the Western and Eastern Sterea Ellada and the Attica. Finally, in the south there are the Northern, Eastern and Western Peloponnese, the Aegean islands and Crete. The majority of the River Basin Districts (RBD) - in which Greece is divided for an effective management of the water resources - use the largest percentages of their abstracted water for agriculture. In 2007, only in the Attica RBD did the water supply take the largest percentage of abstracted water, since the metropolitan area of Athens is the country’s largest urban centre, representing almost half of the country’s population.

1.1.2.WATER USE Water withdrawal in the country by the year 2007 was estimated to be 9,471 million m³. Of this, 61 per cent (5,820 million of m³) was from surface water, and 39 per cent was from groundwater abstraction (3,650 million m³). A very small portion of the water resources (10 million m³) were produced by desalination processes. This water abstraction can be itemized by user sector. By the year 2007, it was estimated that the water dedicated to agriculture reached 8,458 million m³. These resources were used in 128,000km² from the total area equipped for irrigation of 150,000km², which itself represents a significant percentage ( 47.9 per cent) of the area dedicated to cultivation. Water abstraction for urban purposes was estimated to be 846 million m³; and for industrial uses, 167 million m³. The growing demand for drinking water supply and irrigation has resulted in an intense and frequently unreasonable exploitation of water resources. The metropolitan areas of Athens, Thessaloniki and Patra, which account for most of the population and economic activities, are geographically distant from important water resources. On the other hand, peak demands from agriculture, the greatest water consumer, occur mainly in the summer period. During the same period, drinking water consumption is significantly increased due to tourist activity, especially in the islands where there are no water bodies of significant size. Consequently, available water quantities are presently declining and large areas have or soon will become deficient in water. Water demands in many cases are met by transporting water over long distances, resulting in increased capital, operational and maintenance costs.

1.2.WATER QUALITY, ECOSYSTEMS AND HUMAN HEALTH Until the middle of the last century, surface freshwater in Greece mainly followed the slow rhythm of natural changes, with little or no influence from human activities. However from the 1960s, a number of water bodies situated either in the vicinity of urban areas or in regions with increased agricultural and industrial activity, showed signs of pollution. The phenomena associated with Country Overview - Greece pollution have gradually grown and have recently started to influence smaller and previously unaffected water bodies. Urbanization has been a strong driver of land use change over the post-war period in Greece. Eight million people live in urban areas. Urbanization exacerbates some local environmental problems, such as air and noise pollution, traffic congestion and urban waste disposal. Inappropriate waste disposal and management practices may lead to the degradation of surface and ground waters, air pollution and forest fires. In addition, agricultural production has been intensified in productive areas and, in combination with bad land management, can be a threat for the soil. The implementation of the revised Common Agriculture Policy (CAP) by the year 2011 and the introduction of good agricultural practices, are expected to improve the soil condition in Greece (EEA, 2009). The catchments in Greece are marked by high spatial differences in morphologic, climatic, hydrographic, petrographic and vegetative features and variability in pollution impact . As a result, river and stream habitat, hydrochemical regime and biocommunity structure, vary considerably along their courses. In addition, research on ecological quality assessment is limited and geographically restricted, and classification systems are absent. Hence, the assessment of the ecological quality of Greek rivers is a complex task and needs a special approach, since an optimal ‘ecological quality assessment’ can only be achieved through regional adaptations. The nitrate concentrations in groundwater bodies generally reflect the relative importance and intensity of agricultural activities above them. Mean nitrate concentrations in groundwaters are above the background levels (10mg/l NO3), but well below the parametric value of 50mg/l NO3 [Drinking Water Directive]. Between 2000 and 2007, the annual average nitrate concentrations in Greek rivers decreased by approximately -43.5 per cent (from 2.67 to 1.51mg N/l), reflecting the effect of measures to reduce agricultural inputs of nitrate. Nitrate levels in lakes are generally much lower than in rivers and vary between 0.27mg N/l and 0.44 mgN/l over the period 2000 to 2007. The number of monitoring stations in lakes increased from 13 stations in 2000 to 26 stations in 2007. Phosphorus concentrations in Greek rivers and lakes have generally low levels over the period 2000 to 2007. In Greece, existing policies are effective in reducing loading discharges of nutrients and organics. Much progress was made during the period 1980 to 2008 in equipping Greece with sewerage and wastewater treatment systems, thus satisfying the objectives of the EU Urban Waste Water Directive 91/271/EC (UWWD). Water quality and safe sanitation are considered to be of a high priority and measures have been taken. There is a particular challenge in fully covering the water supply needs of the small islands and remote mountainous villages. In order to comply with the UWWD, by the end of 2008, 91 per cent of the population is expected to have wastewater treatment plants meeting the requirements of the directive, and 88 per cent of this population will be served by sewerage systems. There are 290 treatment plants in Greece, with 242 municipal wastewater treatment plants falling under the UWWD, and smaller plants making up the remainder. The authorities responsible for the operation of most treatment plants are the Municipal Services for Water Supply, but in cases of the Psytalia (Athens) and Thessaloniki treatment plants, the responsible authorities are EYDAP and DEYATH respectively.