1. NATIONAL TECHNICAL UNIVERSITY OF ATHENS SCHOOL OF MINING AND METALLURGY KARST SPRINGS OF GREECE MAPPING AND EVALUATION USING GEOGRAPHIC INFORMATION SYSTEM ( G.I.S.) I. Obetzanov, I. Koumantakis, S. Stamataki

2. 1. Scope of the Work  Computer science tools development for the systematization of scattered knowledge  Multilevel information analysis and evaluation Capabilities of the Geographic Information Systems  connection of the database that includes all information about the karst springs’ characteristics to their positions on a digitized map  very efficient way to generate simple or more complex thematic maps  systematic analysis and data interpretation

3. 2. Questioning  The major importance of the karst aquifers in tackling the increasing water demands of Greece  Favorable geological conditions (carbonate rocks) for development of the existing aquifers  A reliable picture of aquifers karst systems distribution in the Hellenic area (combination of the production places and water transportation systems)  Systematization of all relative data Conclusions for planning of the most optimal exploitation of karst waters and for the optimization of karst aquifers storage capacity Essential Research encouragement for karst springs’ full-scale development for any kind of water usage

4. 3. Inventory Data Data for spring’s geographical position : name or toponym, catching area, prefecture, municipality or community, nearest point of recognition: city or village,date of inventory Chemical and physical characteristics: type, flow rate, water and air temperature, water hardness, mineralization, pH, content of cations Ca 2+, Mg 2+, Na +, K +, total cations’ content, content of anions HCO 3 -, SO 4 2-, Cl -, NO 3 - and total anions content. Current stage of development springs’ water usage, exploitation level Springs’ number that have been introduced into the database system: 544 Source of data: Issues of Institute of Geology & Mineral Exploration (I.G.M.E.)

5. Major concentration in Peloponnisos, E.Sterea Hellas, Crete and Macedonia (Carbonate karstified rocks) Observations: Strong dispersion of karst springs all around Greece Different density distribution in each region GEOGRAPHIC DISTRIBUTION OF KARST SPRINGS Data missing from I.G.M.E.

6. SPRINGS’ TYPES Springs’ classification Contact Overflow Coastals Subseas Observations  Dominated springs are those of overflow type which belong mainly to the continental karst aquifers and therefore they can be receptive in regulation possibility of a full-scale exploitation of underground storage capacity of these aquifers  Many coastal karst springs are situated in Southern Greece most of which are of high flow rates and brackish with difficult exploitation conditions

7. Distribution of karst springs according to their ion chloride content KARST SPRINGS’ PHYSICAL AND CHEMICAL CHARACTERISTICS The chemical composition of karst springs’ water depends on : Parameters which determine the hydrochemical features of karst water Lithological structure of the karst system Influence of sea water (springs of coastal karst) 1. Ion chloride content 2. Water hardness 3. Water mineralization

8. Total Water Hardness of Karst Springs Variation of karst springs’ water hardness KARST SPRINGS’ PHYSICAL AND CHEMICAL CHARACTERISTICS Observations : 58% of karst springs have water hardness that varies between 15-50 french degrees and 14% between 50-508 french degrees  karst springs’ water is of hard to very hard type

9. FLOW RATES OF THE KARST SPRINGS Observations: 1.Strong variation of flow rate values: from 36 to 50400 m 3 / h 2.73% of karst springs present flow rate values between 36 - 500 m 3 /h and 21% higher than 500 m 3 / h Distribution of karst springs according to their flow rates

10. DEVELOPMENT OF KARST SPRINGS Observations: A great number of karst springs (126 or 24%) were non usable during the period of their inventory 62 of them belong to the coastal karst system and still remain non usable Low exploitation level: Low exploitation level: karst aquifers’ brackishness karst aquifers’ brackishness not sufficient degree of technology development not sufficient degree of technology development high cost of research and exploitation high cost of research and exploitation

11. KARST SPRINGS’ EXPLOITATION LEVEL Observations: Observations: Important number (83) are used without any kind of exploitation. Most of them are situated in Peloponnisos, in Western Macedonia and in the boundaries of prefecture Magnisia. Distribution of karst springs of according to their exploitation level

12. CONCLUSIONS  The combination of database and Geographic Information System leads to the development of an integrated system of storage, classification and evaluation of all available data about karst springs of Greece  The resulting thematic maps provide information for each parameter that characterizes the spring in relation with its geographic location. The processing and the interpretation of the data provides the way of a comparison analysis of the characteristics among the springs.  The system is very flexible. Each user is allowed to adapt data, in any desired way, to create new type of images, graphical representations and thematic maps.

13.  The geographic distribution of karst springs presents a very strong dispersion with major concentration, based on available data, in Peloponnisos, Eastern Sterea Hellas, Crete and Macedonia.  Dominated springs are those of overflow type and therefore the karst aquifer related to this springs’ type can be receptive in regulation and often in artificial recharge.  The hydrochemical characteristics of most karst springs’ water depend on the lithological nature of the karst system. 79% of the karst springs have very low ions chloride concentration values (up to 50 ppm).  Most of the karst springs present flow rates up to 500 m 3 /h, sufficiently above the lower critical limit that characterize their economical exploitation. Nevertheless, their exploitation is not satisfactory (1 to 4 springs is non usable), while systematic exploitation works have been applied only for 30% of the springs. CONCLUSIONS

14.  Data searching in various studies and reports is required for the karst springs in areas where no systematic inventory has been carried out.  Actualization of those data that concern the exploitation level of karst springs and the exploitation methods that have been applied after 1986.  Observation of flow rates time variation of the karst springs via long-term flow-rate measurements in order to be increased the degree of reliability of the data and of the resulting conclusions.  Particular attention should be paid to the springs of the continental karst and initiatives have to be taken to the direction of their full-scale exploitation in tackling the very serious water problem of Greece.  Research strengthening is needed for new technologies development regarding the exploitation techniques for coastals and subseas karst springs with very high flow rates and significant financial support is required.  It is a subject of national scale of interest that the responsible state organizations must consider as soon as possible. RECOMENDATIONS