Bulletin of the Geological Society of Greece, 2007
The present paper deals with the relationship between precipitation and runoff. Theresults from a... more The present paper deals with the relationship between precipitation and runoff. Theresults from application of the "Antecedent Precipitation Index " (API) techniqueafter introduction of the "delay factor " in eight river basins from NE Achaia-Peloponessos are presented. Measurements of runoff in the exits of the basins werecarried out during the period 1996-1999. Precipitation measurements were usedfrom precipitation gauge stations lying in the river basins. Runoff seems to followthe course of rainfall with a time-lag varying from 30 to 60 days.After trial anderror technique the best fittings of runoff and precipitation graphs were defined.Based on the best fitting equations to calculate the "Antecedent Precipitation Index"the "delay factor" was compiled. High correlation degree between rainfall andrunoff was therefore achieved. The technique may be used to assess the expectedrunoff, based either on real rainfall dataset or on hypothetical sce...
Groundwater plays an important role for urban and agricultural water supply in northern part of P... more Groundwater plays an important role for urban and agricultural water supply in northern part of Peloponnesus. Despite increasing environmental awareness in this area, groundwater is a resource that is being stressed. Groundwater provides about 80% the total quantity of water supply. Distribution of water resources is nonhomogeneous in this region. In general the eastern part is semiarid, whereas the western part is supplied with abundant water. Surface water potential in North Peloponnesus estimated to be 0.9- 1.2x109 m3 y-1. Overexploitation of groundwater and the extensive agriculture has created environmental problems in some aquifers (sea water intrusion, nitrate pollution). Seawater intrusion occurs in some coastal aquifers, where negative water balance has been established. High percentage of the examined samples exceeded the maximum admissible nitrate concentration of 50 mg l-1, set by EU for drinking water. Groundwater in urban areas has been contaminated to varying degrees....
Bulletin of the Geological Society of Greece, 2017
The results of a ground water isotopic research program conducted during the period 2004-2008 by ... more The results of a ground water isotopic research program conducted during the period 2004-2008 by an IGME/Hydrogeology Department team in the area of North Korinthian prefecture are presented here. 69 ground water samples were collected during the period 6/2007 and analyzed in the laboratory of Isotope Hydrology of NCSR…
Bulletin of the Geological Society of Greece, 2017
Hydrogeological maps adopting international standards and covering the whole Greek territory are ... more Hydrogeological maps adopting international standards and covering the whole Greek territory are lacking today in Greece. Sheet D6 - Athina of the International Hydrogeological Map of Europe, scale 1:1,5 million can serve, among many other uses, for such a map. Although relatively limited amount of hydrogeological information is conveyed in the map, because of its small scale, it can serve very well as a guide for information, teaching purposes, planning and scientific work. Besides, because it has fully adopted the standards set from a number of relevant organisations (IAH, IAHS, COHYM, CGMW, UNESCO etc) for the compilation of such kind maps, it can serve equally well as a model for the generation of larger scale Hydrogeological maps.
The implementation of a geographic information system (GIS)/fuzzy spatial decision support system... more The implementation of a geographic information system (GIS)/fuzzy spatial decision support system in the selection of sites for drinking-water pumping boreholes is described. Groundwater is the main source of domestic supply and irrigation in Korinthia prefecture, south-eastern Greece. Water demand has increased considerably over the last 30 years and is mainly met by groundwater abstracted via numerous wells and boreholes. The definition of the most “suitable” site for the drilling of new boreholes is a major issue in this area. A method of allocating suitable locations has been developed based on multicriteria analysis and fuzzy logic. Twelve parameters were finally involved in the model, prearranged into three categories: borehole yield, groundwater quality, and economic and technical constraints. GIS was used to create a classification map of the research area, based on the suitability of each point for the placement of new borehole fields. The coastal part of the study area is completely unsuitable, whereas high values of suitability are recorded in the south-western part. The study demonstrated that the method of multicriteria analysis in combination with fuzzy logic is a useful tool for selecting the best sites for new borehole drilling on a regional scale. The results could be used by local authorities and decision-makers for integrated groundwater resources management.RésuméLa mise en œuvre d’un système d’information géographique (SIG)/système spatialisée de logique floue d’aide à la décision pour la sélection de sites de forages d’eau potable est décrite. Les eaux souterraines constituent la principale source d’approvisionnement en eau pour des usages domestiques et agricoles (irrigation) dans la préfecture de Corinthe, dans le Sud-Est de la Grèce. La demande en eau a augmenté de manière considérable au cours des 30 dernières années et est principalement satisfaite par le prélèvement d’eaux souterraines au niveau de nombreux puits et forages. La définition de l’emplacement le plus approprié pour le forage de nouveaux puits est une question centrale dans ce domaine. Une méthode de sélection des sites appropriés a été développée sur la base de l’analyse multicritère et la logique floue. Douze paramètres ont finalement été considérés dans le modèle, arrangés selon trois catégories: le rendement du forage, la qualité des eaux souterraines, et les contraintes économiques et techniques. Le SIG a été utilisé pour créer une carte de classification au niveau de la zone de recherche, sur la base de la pertinence de chaque point pour la localisation de nouveaux champs de captage. La partie côtière de la zone d’étude est totalement inadaptée, alors que les valeurs élevée d’aptitudes sont enregistrées dans la partie sud-ouest. L’étude a démontré que la méthode d’analyse multicritère combinée à la logique floue est un outil utile pour la sélection des meilleurs sites pour implanter de nouveaux forages à l’échelle régionale. Les résultats pourraient être utilisés par les autorités locales et les décideurs pour une gestion intégrée des ressources en eau souterraine.ResumenSe describe la implementación de un sistema de información geográfica (GIS)/sistema de apoyo a la toma de decisiones espaciales difusas en la selección de sitios para perforaciones de bombeo de agua potable. El agua subterránea en la principal fuente de abastecimiento doméstico e irrigación en la prefectura de Korinthia, sudeste de Grecia. La demanda de agua se ha incrementado considerablemente durante los últimos 30 años y está principalmente satisfecha por el agua subterránea extraída por numerosos pozos y perforaciones. La definición del sitio más adecuado para las perforaciones de nuevos pozos es un tema mayor en esta área. Se ha desarrollado un método para la ubicación apropiada de las locaciones basado en análisis de multicriterio y lógica difusa. Doce parámetros fueron finalmente involucrados en el modelo, preestablecidos en tres categorías: rendimiento de la perforación, calidad de agua subterránea, y limitantes técnicas y económicas. Se usó el GIS para crear un mapa de clasificación del área investigada, basado en la pertinencia de cada uno de los puntos para la ubicación de nuevos campos de pozos. La parte costera del área de estudio es completamente inadecuada, mientras que se han registrado valores altos de oportunidad en la parte sudoeste. El estudio demostró que el método de análisis multicriterio en combinación con la lógica difusa es una herramienta útil para seleccionar los mejores sitios para las nuevas perforaciones en escala regional. Los resultados podrían ser usados por autoridades locales y por tomadores de decisión para el manejo integrado de los recursos de agua…
Groundwater and saline intrusion. Selected papers from the 18th Salt Water Intrusion Meeting. Car... more Groundwater and saline intrusion. Selected papers from the 18th Salt Water Intrusion Meeting. Cartagena, Spain. Publ. Geological Survey of Spain (ed. L. Araguas, E. Custodio, M. Manzano), 465-480. ... Enter the email address you signed up with, and we'll send an ...
The present study is an attempt to implement several spatial interpolation methods for the distri... more The present study is an attempt to implement several spatial interpolation methods for the distribution of groundwater level in a wider area with multiple aquifers having variable hydraulic characteristics. Moreover, the goal of this study is to compare the results of these methods and check their accuracy and reliability, considering mainly the physical meaning of the outcome. Finally, we try to figure out which of these methods manage to identify hydrogeological features like groundwater divides, hydraulic conductivity barriers and no flow boundaries, and to highlight the hydraulic relationship between aquifers. Exploratory Spatial Data Analysis proved to be a necessary step prior to the implementation of spatial interpolation methods, since normalization of datasets, removal of general trends and data declustering was necessary for the proper implementation of geostatistical methods and reduction of the uncertainty of the results. Inverse Distance Weight, Radial basis functions, ...
The implementation of a geographic information system (GIS)/fuzzy spatial decision support system... more The implementation of a geographic information system (GIS)/fuzzy spatial decision support system in the selection of sites for drinking-water pumping boreholes is described. Groundwater is the main source of domestic supply and irrigation in Korinthia prefecture, south-eastern Greece. Water demand has increased considerably over the last 30 years and is mainly met by groundwater abstracted via numerous wells and boreholes. The definition of the most “suitable” site for the drilling of new boreholes is a major issue in this area. A method of allocating suitable locations has been developed based on multicriteria analysis and fuzzy logic. Twelve parameters were finally involved in the model, prearranged into three categories: borehole yield, groundwater quality, and economic and technical constraints. GIS was used to create a classification map of the research area, based on the suitability of each point for the placement of new borehole fields. The coastal part of the study area is completely unsuitable, whereas high values of suitability are recorded in the south-western part. The study demonstrated that the method of multicriteria analysis in combination with fuzzy logic is a useful tool for selecting the best sites for new borehole drilling on a regional scale. The results could be used by local authorities and decision-makers for integrated groundwater resources management.
Advances in the Research of Aquatic Environment, Environmental Earth Sciences, Springer Berlin Heidelberg, p. 299-306
During the period 2004-2008 a hydrogeological investigation project was conducted by an IGME/Hydr... more During the period 2004-2008 a hydrogeological investigation project was conducted by an IGME/Hydrogeology Department team in the area of North Peloponnesus, funded by the 3rd EU Framework Directive budget. In 2008 using the results of this investigation and implementing article 5 of Water Framework Directive 60/2000/EU as well as articles of Ground Water Directive 2006/118/EU, eleven ground water bodies (management units) were able to be identified in this area. Using the DPSIR criteria six of them found to be needed further characterization and two out of these six were concluded not to be able to fulfil the required good (quantitative and chemical) groundwater status by 2015. All these results are presented here.
Advances in the Research of Aquatic Environment, Environmental Earth Sciences, Springer Berlin Heidelberg, p. 299-306
During the period 2004-2008 a hydrogeological investigation project was conducted by an IGME/Hydr... more During the period 2004-2008 a hydrogeological investigation project was conducted by an IGME/Hydrogeology Department team in the area of North Peloponnesus, funded by the 3rd EU Framework Directive budget. In 2008 using the results of this investigation and implementing article 5 of Water Framework Directive 60/2000/EU as well as articles of Ground Water Directive 2006/118/EU, eleven ground water bodies (management units) were able to be identified in this area. Using the DPSIR criteria six of them found to be needed further characterization and two out of these six were concluded not to be able to fulfil the required good (quantitative and chemical) groundwater status by 2015. All these results are presented here.
The present paper deals with the relationship between precipitation and runoff. The results from ... more The present paper deals with the relationship between precipitation and runoff. The results from application of the " Antecedent Precipitation Index " (API) technique after introduction of the " delay factor " in eight river basins from NE Achaia-Peloponessos are presented. Measurements of runoff in the exits of the basins were carried out during the period 1996-1999. Precipitation measurements were used from precipitation gauge stations lying in the river basins. Runoff seems to follow the course of rainfall with a time-lag varying from 30 to 60 days.After trial and error technique the best fittings of runoff and precipitation graphs were defined. Based on the best fitting equations to calculate the " Antecedent Precipitation Index " the " delay factor " was compiled. High correlation degree between rainfall and runoff was therefore achieved. The technique may be used to assess the expected runoff, based either on real rainfall dataset or on hypothetical scenarios. The " delay factor " of the runoff response to the precipitation is highly correlated with geomorphological and hydrogeological characteristics of the river basins.
Hydrogeological maps adopting international standards and covering the whole Greek territory are ... more Hydrogeological maps adopting international standards and covering the whole Greek territory are lacking today in Greece. Sheet D6-Athina of the International Hydrogeological Map of Europe, scale 1:1,5 million can serve, among many other uses, for such a map. Although relatively limited amount of hydrogeological information is conveyed in the map, because of its small scale, it can serve very well as a guide for information, teaching purposes, planning and scientific work. Besides , because it has fully adopted the standards set from a number of relevant organisations (IAH, IAHS, COHYM, CGMW, UNESCO etc) for the compilation of such kind maps, it can serve equally well as a model for the generation of larger scale Hydrogeological maps.
The assessment of groundwater vulnerability to pollution has proved to be an effective tool for t... more The assessment of groundwater vulnerability to pollution has proved to be an effective tool for the delin-eation of protection zones in areas affected by groundwater contamination due to intensive fertilizer applications. By modifying and optimizing the well known and widely used DRASTIC model it was possible to predict the intrinsic vulnerability to pollution as well as the groundwater pollution risk more accurately. This method incorporated the use of simple statistical and geostatistical techniques for the revision of the factor ratings and weightings of all the DRASTIC parameters under a GIS environment. The criterion for these modifications was the correlation coefficient of each parameter with the nitrates concentration in groundwater. On the basis of their statistical significance, some parameters were subtracted from the DRASTIC equation, while land use was considered as an additional DRASTIC parameter. Following the above-mentioned modifications, the correlation coefficient between groundwater pollution risk and nitrates concentration was considerably improved and rose to 33% higher than the original method. The model was applied to a part of Trifilia province, Greece, which is considered to be a typical Mediterranean region with readily available hydrogeological and hydrochemical data.
Groundwater plays an important role for urban and agricultural water supply in northern part of P... more Groundwater plays an important role for urban and agricultural water supply in northern part of Peloponnesus. Despite increasing environmental awareness in this area, groundwater is a resource that is being stressed. Groundwater provides about 80% the total quantity of water supply. Distribution of water resources is nonhomogeneous in this region. In general the eastern part is semiarid, whereas the western part is supplied with abundant water. Surface water potential in North Peloponnesus estimated to be 0.9-1.2x10 9 m 3 y-1. Overexploitation of groundwater and the extensive agriculture has created environmental problems in some aquifers (sea water intrusion, nitrate pollution). Seawater intrusion occurs in some coastal aquifers, where negative water balance has been established. High percentage of the examined samples exceeded the maximum admissible nitrate concentration of 50 mg l-1 , set by EU for drinking water. Groundwater in urban areas has been contaminated to varying degrees. The water quality is classified into Ca-HCO 3 type (fresh water) and Na-HCO 3 or Na-Cl type (brackish waters) in the coastal part, due to seawater intrusion. Some recommendations are made in order to safeguard high water quality and to develop new ways of providing water source in the study area. Moreover, an integrated and comprehensive management scheme should be applied, aiming at sustainability of water resources and based on surface water and groundwater exploitation, simultaneously.
This article was originally published in a journal published by Elsevier, and the attached copy i... more This article was originally published in a journal published by Elsevier, and the attached copy is provided by Elsevier for the author's benefit and for the benefit of the author's institution, for non-commercial research and educational use including without limitation use in instruction at your institution, sending it to specific colleagues that you know, and providing a copy to your institution's administrator. All other uses, reproduction and distribution, including without limitation commercial reprints, selling or licensing copies or access, or posting on open internet sites, your personal or institution's website or repository, are prohibited. For exceptions, permission may be sought for such use through Elsevier's permissions site at: http://www.elsevier.com/locate/permissionusematerial Summary The assessment of groundwater vulnerability to pollution has proved to be an effective tool for the delineation of protection zones in areas affected by groundwater contamination due to the intensive fertilizer applications. The main objective of this study has been to develop and check the results of three hybrid methods for specific aquifer vulnerability assessment based upon the parameters, classification and rating principles of the well known DRASTIC model. The first method, proposed by [Panagopoulos, G., Antonakos, A., Lambrakis, N., 2006. Optimization of DRASTIC model for groundwater vulnerability assessment, by the use of simple statistical methods and GIS. Hydrogeology Journal (published online).], has proved to be an effective way to modify the DRASTIC model in order to achieve better correlation with actual nitrates occurrence. Descriptive statistics and simple statistical tests on a hydrochemical data-set are used by the method in order to change the initial factor ratings and factor weights participating in the vulnerability assessment equation. The other two methods were developed by the use of logistic regression and weights of evidence statistical procedures and the use of the same hydrochemical dataset, and attain relatively high correlation factors when referring to sample points while correlation was significantly lower for the entire distributions of vulnerability estimation and actual nitrates occurrence.
The main objective of this work is to determine the parameters of hydrological balance for severa... more The main objective of this work is to determine the parameters of hydrological balance for several basins in the prefecture of Korinthia (SE Greece), using hydrometeorological data and geographic information systems (GIS) technology. Multiple linear regression and GIS were used to estimate the spatial distribution of rainfall. The largest precipitation amounts occur in the SW part of the region and decrease towards the eastern and northern coastal parts. The long term mean annual rainfall is 1.39×10 9 m 3. Based on the Thornthwaite method, infiltration and streamflow were estimated to be 0.29×10 9 m 3 /yr and 0.38×10 9 m 3 /yr, respectively. The unequal distribution of rainfall results in water surplus in the western part of Korinthia prefecture and water deficit in the eastern. We conclude that he estimation of hydrologic balance is a useful tool in order to establish sustainable water resources management in each hydrological basin.
Bulletin of the Geological Society of Greece, 2007
The present paper deals with the relationship between precipitation and runoff. Theresults from a... more The present paper deals with the relationship between precipitation and runoff. Theresults from application of the "Antecedent Precipitation Index " (API) techniqueafter introduction of the "delay factor " in eight river basins from NE Achaia-Peloponessos are presented. Measurements of runoff in the exits of the basins werecarried out during the period 1996-1999. Precipitation measurements were usedfrom precipitation gauge stations lying in the river basins. Runoff seems to followthe course of rainfall with a time-lag varying from 30 to 60 days.After trial anderror technique the best fittings of runoff and precipitation graphs were defined.Based on the best fitting equations to calculate the "Antecedent Precipitation Index"the "delay factor" was compiled. High correlation degree between rainfall andrunoff was therefore achieved. The technique may be used to assess the expectedrunoff, based either on real rainfall dataset or on hypothetical sce...
Groundwater plays an important role for urban and agricultural water supply in northern part of P... more Groundwater plays an important role for urban and agricultural water supply in northern part of Peloponnesus. Despite increasing environmental awareness in this area, groundwater is a resource that is being stressed. Groundwater provides about 80% the total quantity of water supply. Distribution of water resources is nonhomogeneous in this region. In general the eastern part is semiarid, whereas the western part is supplied with abundant water. Surface water potential in North Peloponnesus estimated to be 0.9- 1.2x109 m3 y-1. Overexploitation of groundwater and the extensive agriculture has created environmental problems in some aquifers (sea water intrusion, nitrate pollution). Seawater intrusion occurs in some coastal aquifers, where negative water balance has been established. High percentage of the examined samples exceeded the maximum admissible nitrate concentration of 50 mg l-1, set by EU for drinking water. Groundwater in urban areas has been contaminated to varying degrees....
Bulletin of the Geological Society of Greece, 2017
The results of a ground water isotopic research program conducted during the period 2004-2008 by ... more The results of a ground water isotopic research program conducted during the period 2004-2008 by an IGME/Hydrogeology Department team in the area of North Korinthian prefecture are presented here. 69 ground water samples were collected during the period 6/2007 and analyzed in the laboratory of Isotope Hydrology of NCSR…
Bulletin of the Geological Society of Greece, 2017
Hydrogeological maps adopting international standards and covering the whole Greek territory are ... more Hydrogeological maps adopting international standards and covering the whole Greek territory are lacking today in Greece. Sheet D6 - Athina of the International Hydrogeological Map of Europe, scale 1:1,5 million can serve, among many other uses, for such a map. Although relatively limited amount of hydrogeological information is conveyed in the map, because of its small scale, it can serve very well as a guide for information, teaching purposes, planning and scientific work. Besides, because it has fully adopted the standards set from a number of relevant organisations (IAH, IAHS, COHYM, CGMW, UNESCO etc) for the compilation of such kind maps, it can serve equally well as a model for the generation of larger scale Hydrogeological maps.
The implementation of a geographic information system (GIS)/fuzzy spatial decision support system... more The implementation of a geographic information system (GIS)/fuzzy spatial decision support system in the selection of sites for drinking-water pumping boreholes is described. Groundwater is the main source of domestic supply and irrigation in Korinthia prefecture, south-eastern Greece. Water demand has increased considerably over the last 30 years and is mainly met by groundwater abstracted via numerous wells and boreholes. The definition of the most “suitable” site for the drilling of new boreholes is a major issue in this area. A method of allocating suitable locations has been developed based on multicriteria analysis and fuzzy logic. Twelve parameters were finally involved in the model, prearranged into three categories: borehole yield, groundwater quality, and economic and technical constraints. GIS was used to create a classification map of the research area, based on the suitability of each point for the placement of new borehole fields. The coastal part of the study area is completely unsuitable, whereas high values of suitability are recorded in the south-western part. The study demonstrated that the method of multicriteria analysis in combination with fuzzy logic is a useful tool for selecting the best sites for new borehole drilling on a regional scale. The results could be used by local authorities and decision-makers for integrated groundwater resources management.RésuméLa mise en œuvre d’un système d’information géographique (SIG)/système spatialisée de logique floue d’aide à la décision pour la sélection de sites de forages d’eau potable est décrite. Les eaux souterraines constituent la principale source d’approvisionnement en eau pour des usages domestiques et agricoles (irrigation) dans la préfecture de Corinthe, dans le Sud-Est de la Grèce. La demande en eau a augmenté de manière considérable au cours des 30 dernières années et est principalement satisfaite par le prélèvement d’eaux souterraines au niveau de nombreux puits et forages. La définition de l’emplacement le plus approprié pour le forage de nouveaux puits est une question centrale dans ce domaine. Une méthode de sélection des sites appropriés a été développée sur la base de l’analyse multicritère et la logique floue. Douze paramètres ont finalement été considérés dans le modèle, arrangés selon trois catégories: le rendement du forage, la qualité des eaux souterraines, et les contraintes économiques et techniques. Le SIG a été utilisé pour créer une carte de classification au niveau de la zone de recherche, sur la base de la pertinence de chaque point pour la localisation de nouveaux champs de captage. La partie côtière de la zone d’étude est totalement inadaptée, alors que les valeurs élevée d’aptitudes sont enregistrées dans la partie sud-ouest. L’étude a démontré que la méthode d’analyse multicritère combinée à la logique floue est un outil utile pour la sélection des meilleurs sites pour implanter de nouveaux forages à l’échelle régionale. Les résultats pourraient être utilisés par les autorités locales et les décideurs pour une gestion intégrée des ressources en eau souterraine.ResumenSe describe la implementación de un sistema de información geográfica (GIS)/sistema de apoyo a la toma de decisiones espaciales difusas en la selección de sitios para perforaciones de bombeo de agua potable. El agua subterránea en la principal fuente de abastecimiento doméstico e irrigación en la prefectura de Korinthia, sudeste de Grecia. La demanda de agua se ha incrementado considerablemente durante los últimos 30 años y está principalmente satisfecha por el agua subterránea extraída por numerosos pozos y perforaciones. La definición del sitio más adecuado para las perforaciones de nuevos pozos es un tema mayor en esta área. Se ha desarrollado un método para la ubicación apropiada de las locaciones basado en análisis de multicriterio y lógica difusa. Doce parámetros fueron finalmente involucrados en el modelo, preestablecidos en tres categorías: rendimiento de la perforación, calidad de agua subterránea, y limitantes técnicas y económicas. Se usó el GIS para crear un mapa de clasificación del área investigada, basado en la pertinencia de cada uno de los puntos para la ubicación de nuevos campos de pozos. La parte costera del área de estudio es completamente inadecuada, mientras que se han registrado valores altos de oportunidad en la parte sudoeste. El estudio demostró que el método de análisis multicriterio en combinación con la lógica difusa es una herramienta útil para seleccionar los mejores sitios para las nuevas perforaciones en escala regional. Los resultados podrían ser usados por autoridades locales y por tomadores de decisión para el manejo integrado de los recursos de agua…
Groundwater and saline intrusion. Selected papers from the 18th Salt Water Intrusion Meeting. Car... more Groundwater and saline intrusion. Selected papers from the 18th Salt Water Intrusion Meeting. Cartagena, Spain. Publ. Geological Survey of Spain (ed. L. Araguas, E. Custodio, M. Manzano), 465-480. ... Enter the email address you signed up with, and we'll send an ...
The present study is an attempt to implement several spatial interpolation methods for the distri... more The present study is an attempt to implement several spatial interpolation methods for the distribution of groundwater level in a wider area with multiple aquifers having variable hydraulic characteristics. Moreover, the goal of this study is to compare the results of these methods and check their accuracy and reliability, considering mainly the physical meaning of the outcome. Finally, we try to figure out which of these methods manage to identify hydrogeological features like groundwater divides, hydraulic conductivity barriers and no flow boundaries, and to highlight the hydraulic relationship between aquifers. Exploratory Spatial Data Analysis proved to be a necessary step prior to the implementation of spatial interpolation methods, since normalization of datasets, removal of general trends and data declustering was necessary for the proper implementation of geostatistical methods and reduction of the uncertainty of the results. Inverse Distance Weight, Radial basis functions, ...
The implementation of a geographic information system (GIS)/fuzzy spatial decision support system... more The implementation of a geographic information system (GIS)/fuzzy spatial decision support system in the selection of sites for drinking-water pumping boreholes is described. Groundwater is the main source of domestic supply and irrigation in Korinthia prefecture, south-eastern Greece. Water demand has increased considerably over the last 30 years and is mainly met by groundwater abstracted via numerous wells and boreholes. The definition of the most “suitable” site for the drilling of new boreholes is a major issue in this area. A method of allocating suitable locations has been developed based on multicriteria analysis and fuzzy logic. Twelve parameters were finally involved in the model, prearranged into three categories: borehole yield, groundwater quality, and economic and technical constraints. GIS was used to create a classification map of the research area, based on the suitability of each point for the placement of new borehole fields. The coastal part of the study area is completely unsuitable, whereas high values of suitability are recorded in the south-western part. The study demonstrated that the method of multicriteria analysis in combination with fuzzy logic is a useful tool for selecting the best sites for new borehole drilling on a regional scale. The results could be used by local authorities and decision-makers for integrated groundwater resources management.
Advances in the Research of Aquatic Environment, Environmental Earth Sciences, Springer Berlin Heidelberg, p. 299-306
During the period 2004-2008 a hydrogeological investigation project was conducted by an IGME/Hydr... more During the period 2004-2008 a hydrogeological investigation project was conducted by an IGME/Hydrogeology Department team in the area of North Peloponnesus, funded by the 3rd EU Framework Directive budget. In 2008 using the results of this investigation and implementing article 5 of Water Framework Directive 60/2000/EU as well as articles of Ground Water Directive 2006/118/EU, eleven ground water bodies (management units) were able to be identified in this area. Using the DPSIR criteria six of them found to be needed further characterization and two out of these six were concluded not to be able to fulfil the required good (quantitative and chemical) groundwater status by 2015. All these results are presented here.
Advances in the Research of Aquatic Environment, Environmental Earth Sciences, Springer Berlin Heidelberg, p. 299-306
During the period 2004-2008 a hydrogeological investigation project was conducted by an IGME/Hydr... more During the period 2004-2008 a hydrogeological investigation project was conducted by an IGME/Hydrogeology Department team in the area of North Peloponnesus, funded by the 3rd EU Framework Directive budget. In 2008 using the results of this investigation and implementing article 5 of Water Framework Directive 60/2000/EU as well as articles of Ground Water Directive 2006/118/EU, eleven ground water bodies (management units) were able to be identified in this area. Using the DPSIR criteria six of them found to be needed further characterization and two out of these six were concluded not to be able to fulfil the required good (quantitative and chemical) groundwater status by 2015. All these results are presented here.
The present paper deals with the relationship between precipitation and runoff. The results from ... more The present paper deals with the relationship between precipitation and runoff. The results from application of the " Antecedent Precipitation Index " (API) technique after introduction of the " delay factor " in eight river basins from NE Achaia-Peloponessos are presented. Measurements of runoff in the exits of the basins were carried out during the period 1996-1999. Precipitation measurements were used from precipitation gauge stations lying in the river basins. Runoff seems to follow the course of rainfall with a time-lag varying from 30 to 60 days.After trial and error technique the best fittings of runoff and precipitation graphs were defined. Based on the best fitting equations to calculate the " Antecedent Precipitation Index " the " delay factor " was compiled. High correlation degree between rainfall and runoff was therefore achieved. The technique may be used to assess the expected runoff, based either on real rainfall dataset or on hypothetical scenarios. The " delay factor " of the runoff response to the precipitation is highly correlated with geomorphological and hydrogeological characteristics of the river basins.
Hydrogeological maps adopting international standards and covering the whole Greek territory are ... more Hydrogeological maps adopting international standards and covering the whole Greek territory are lacking today in Greece. Sheet D6-Athina of the International Hydrogeological Map of Europe, scale 1:1,5 million can serve, among many other uses, for such a map. Although relatively limited amount of hydrogeological information is conveyed in the map, because of its small scale, it can serve very well as a guide for information, teaching purposes, planning and scientific work. Besides , because it has fully adopted the standards set from a number of relevant organisations (IAH, IAHS, COHYM, CGMW, UNESCO etc) for the compilation of such kind maps, it can serve equally well as a model for the generation of larger scale Hydrogeological maps.
The assessment of groundwater vulnerability to pollution has proved to be an effective tool for t... more The assessment of groundwater vulnerability to pollution has proved to be an effective tool for the delin-eation of protection zones in areas affected by groundwater contamination due to intensive fertilizer applications. By modifying and optimizing the well known and widely used DRASTIC model it was possible to predict the intrinsic vulnerability to pollution as well as the groundwater pollution risk more accurately. This method incorporated the use of simple statistical and geostatistical techniques for the revision of the factor ratings and weightings of all the DRASTIC parameters under a GIS environment. The criterion for these modifications was the correlation coefficient of each parameter with the nitrates concentration in groundwater. On the basis of their statistical significance, some parameters were subtracted from the DRASTIC equation, while land use was considered as an additional DRASTIC parameter. Following the above-mentioned modifications, the correlation coefficient between groundwater pollution risk and nitrates concentration was considerably improved and rose to 33% higher than the original method. The model was applied to a part of Trifilia province, Greece, which is considered to be a typical Mediterranean region with readily available hydrogeological and hydrochemical data.
Groundwater plays an important role for urban and agricultural water supply in northern part of P... more Groundwater plays an important role for urban and agricultural water supply in northern part of Peloponnesus. Despite increasing environmental awareness in this area, groundwater is a resource that is being stressed. Groundwater provides about 80% the total quantity of water supply. Distribution of water resources is nonhomogeneous in this region. In general the eastern part is semiarid, whereas the western part is supplied with abundant water. Surface water potential in North Peloponnesus estimated to be 0.9-1.2x10 9 m 3 y-1. Overexploitation of groundwater and the extensive agriculture has created environmental problems in some aquifers (sea water intrusion, nitrate pollution). Seawater intrusion occurs in some coastal aquifers, where negative water balance has been established. High percentage of the examined samples exceeded the maximum admissible nitrate concentration of 50 mg l-1 , set by EU for drinking water. Groundwater in urban areas has been contaminated to varying degrees. The water quality is classified into Ca-HCO 3 type (fresh water) and Na-HCO 3 or Na-Cl type (brackish waters) in the coastal part, due to seawater intrusion. Some recommendations are made in order to safeguard high water quality and to develop new ways of providing water source in the study area. Moreover, an integrated and comprehensive management scheme should be applied, aiming at sustainability of water resources and based on surface water and groundwater exploitation, simultaneously.
This article was originally published in a journal published by Elsevier, and the attached copy i... more This article was originally published in a journal published by Elsevier, and the attached copy is provided by Elsevier for the author's benefit and for the benefit of the author's institution, for non-commercial research and educational use including without limitation use in instruction at your institution, sending it to specific colleagues that you know, and providing a copy to your institution's administrator. All other uses, reproduction and distribution, including without limitation commercial reprints, selling or licensing copies or access, or posting on open internet sites, your personal or institution's website or repository, are prohibited. For exceptions, permission may be sought for such use through Elsevier's permissions site at: http://www.elsevier.com/locate/permissionusematerial Summary The assessment of groundwater vulnerability to pollution has proved to be an effective tool for the delineation of protection zones in areas affected by groundwater contamination due to the intensive fertilizer applications. The main objective of this study has been to develop and check the results of three hybrid methods for specific aquifer vulnerability assessment based upon the parameters, classification and rating principles of the well known DRASTIC model. The first method, proposed by [Panagopoulos, G., Antonakos, A., Lambrakis, N., 2006. Optimization of DRASTIC model for groundwater vulnerability assessment, by the use of simple statistical methods and GIS. Hydrogeology Journal (published online).], has proved to be an effective way to modify the DRASTIC model in order to achieve better correlation with actual nitrates occurrence. Descriptive statistics and simple statistical tests on a hydrochemical data-set are used by the method in order to change the initial factor ratings and factor weights participating in the vulnerability assessment equation. The other two methods were developed by the use of logistic regression and weights of evidence statistical procedures and the use of the same hydrochemical dataset, and attain relatively high correlation factors when referring to sample points while correlation was significantly lower for the entire distributions of vulnerability estimation and actual nitrates occurrence.
The main objective of this work is to determine the parameters of hydrological balance for severa... more The main objective of this work is to determine the parameters of hydrological balance for several basins in the prefecture of Korinthia (SE Greece), using hydrometeorological data and geographic information systems (GIS) technology. Multiple linear regression and GIS were used to estimate the spatial distribution of rainfall. The largest precipitation amounts occur in the SW part of the region and decrease towards the eastern and northern coastal parts. The long term mean annual rainfall is 1.39×10 9 m 3. Based on the Thornthwaite method, infiltration and streamflow were estimated to be 0.29×10 9 m 3 /yr and 0.38×10 9 m 3 /yr, respectively. The unequal distribution of rainfall results in water surplus in the western part of Korinthia prefecture and water deficit in the eastern. We conclude that he estimation of hydrologic balance is a useful tool in order to establish sustainable water resources management in each hydrological basin.
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