The present study focused on the Upper Cretaceous to Middle Miocene sequence in the Central Gulf of Suez, Egypt. The Upper Cretaceous to Middle Miocene sequence in the October field is thick and deeply buried, consisting mainly of brown limestone, chalk limestone, and reefal limestone intercalated with clastic shale. This study integrated various datasets, including total organic carbon (TOC), Rock-Eval pyrolysis, visual kerogen examination, vitrinite reflectance (%Ro), and bottom-hole temperature measurements. The main objective of this study is to delineate the source rock characteristics of these strata regarding organic richness, thermal maturity, kerogen type, timing of hydrocarbon transformation and generation. The Upper Cretaceous Brown Limestone Formation is represented by 135 samples from four wells and is considered to be a fair to excellent source rock, primarily containing type I and II kerogen. It is immature to early mature, generating oil with a low to intermediate level of hydrocarbon conversion. The Eocene Thebes Formation is represented by 105 samples from six wells and is considered to be a good to fair oil source rock with some potential for gas, primarily containing type II and II/III kerogen. Most samples are immature with a low level of hydrocarbon conversion while few are mature having an intermediate degree of hydrocarbon conversion. The Middle Miocene Lower Rudeis Formation is represented by 8 samples from two wells and considered to be a fair but immature source rock, primarily containing type III kerogen with a low level of conversion representing a potential source for gas. The Middle Miocene Belayim Formation is represented by 29 samples from three wells and is considered to be a poor to good source rock, primarily containing kerogen type II and III. Most samples are immature with a low level of hydrocarbon conversion while few are mature having an intermediate degree of hydrocarbon conversion. 1D basin model A-5 well shows that the Upper Cretaceous Brown Limestone source rock entered the early oil window at 39 Ma, progressed to the main oil window by 13 Ma, and remains in this stage today. The Eocene Thebes source rock began generating hydrocarbons at 21.3 Ma, advanced to the main oil window at 11 Ma, and has been in the late oil window since 1.6 Ma. The Middle Miocene Lower Rudeis source rock entered the early oil window at 12.6 Ma, transitioned to the main oil window at 5.7 Ma, where it remains active. In contrast, the Middle Miocene Belayim source rock has not yet reached the early oil window and remains immature, with values ranging from 0.00 to 0.55 % Ro. The transformation ratio plot shows that the Brown Limestone Formation began transforming into the Upper Cretaceous (73 Ma), reaching 29.84% by the Miocene (14.3 Ma). The Thebes Formation initiated transformation in the Late Eocene (52.3 Ma) and reached 6.42% by 16.4 Ma. The Lower Rudeis Formation began in the Middle Miocene (18.7 Ma), reaching 3.59% by 9.2 Ma. The Belayim Formation started its transformation at 11.2 Ma, reaching 0.63% by 6.8 Ma.

The global need for energy has risen sharply recently. A global shift to clean energy is urgently needed to avoid catastrophic climate impacts. Hydrogen (H2) has emerged as a potential alternative energy source with near-net-zero emissions. In the African continent, for sustainable access to clean energy and the transition away from fossil fuels, this paper presents a new approach through which waste energy can produce green hydrogen from biomass. Bio-based hydrogen employing organic waste and biomass is recommended using biological (anaerobic digestion and fermentation) processes for scalable, cheaper, and low-carbon hydrogen. By reviewing all methods for producing green hydrogen, dark fermentation can be applied in developed and developing countries without putting pressure on natural resources such as freshwater and rare metals, the primary feedstocks used in producing green hydrogen by electrolysis. It can be expanded to produce medium- and long-term green hydrogen without relying heavily on energy sources or building expensive infrastructure. Implementing the dark fermentation process can support poor communities in producing green hydrogen as an energy source regardless of political and tribal conflicts, unlike other methods that require political stability. In addition, this approach does not require the approval of new legislation. Such processes can ensure the minimization of waste and greenhouse gases. To achieve cost reduction in hydrogen production by 2030, governments should develop a strategy to expand the use of dark fermentation reactors and utilize hot water from various industrial processes (waste energy recovery from hot wastewater).

Using geochemical and pumping test data from 80 groundwater wells, the chemical, hydrologic, and hydraulic properties of the fractured Eocene carbonate aquifer located west of the Al-Minya district, the Western Desert, Egypt, have been characterized and determined to guarantee sustainable management of groundwater resources under large-scale desert reclamation projects. The hydrochemical data show that groundwater from the fractured Eocene carbonate aquifer has a high concentration of Na+ and Cl− and varies in salinity from 2176 to 2912 mg/L (brackish water). Water–rock interaction and ion exchange processes are the most dominant processes controlling groundwater composition. The carbonate aquifer exists under confined to semi-confined conditions, and the depth to groundwater increases eastward. From the potentiometric head data, deep-seated faults are the suggested pathways for gas-rich water ascending from the deep Nubian aquifer system into the overlying shallow carbonate aquifer. This mechanism enhances the dissolution and karstification of carbonate rocks, especially in the vicinity of faulted sites, and is supported by the significant loss of mud circulation during well drilling operations. The average estimated hydraulic parameters, based on the analysis of step-drawdown, long-duration pumping and recovery tests, indicate that the Eocene carbonate aquifer has a wide range of transmissivity (T) that is between 336.39 and 389,309.28 m2/d (average: 18,405.21 m2/d), hydraulic conductivity (K) between 1.31 and 1420.84 m/d (average: 70.29 m/d), and specific capacity (Sc) between 44.4 and 17,376.24 m2/d (average: 45.24 m2/d). On the other hand, the performance characteristics of drilled wells show that well efficiency ranges between 0.47 and 97.08%, and well losses range between 2.92 and 99.53%. In addition to variations in carbonate aquifer thickness and clay/shale content, the existence of strong karstification features, i.e., fissures, fractures or caverns, and solution cavities, in the Eocene carbonate aquifer are responsible for variability in the K and T values. The observed high well losses might be related to turbulent flow within and adjacent to the wells drilled in conductive fracture zones. The current approach can be further used to enhance local aquifer models and improve strategies for identifying the most productive zones in similar aquifer systems.

The Wadi El-Rayan lakes are important aquatic environments located at the border of the great North African Sahara. Quantifying the temporal changes in these lakes due to natural and/or anthropogenic stressors is critical when assessing potential impacts on aquatic ecosystem health and the sustainability of fisheries. To detect the changes in fish communities and their drivers, the landing composition of the Wadi El-Rayan lakes over the past 30 years was quantitatively analyzed. The areas of the lakes dramatically decreased from 110 km2 in 1991 to 73 km2 in 2019. The loss of the lake area was attributed to climate warming, where the evaporation rate exceeded the volume of recharge and the recharge decreased due to an increase in agriculture and aquaculture. The total landing significantly increased in the past three decades due to an increase in the fishing effort (number of licensed boats). Nile tilapia, mullet, and grass carp dominated the landings. The pelagic-to-demersal ratio indicated a shift in the fish community composition towards demersal species. This shift was attributed to an increase in the eutrophication level. The fish communities of the landing data were clustered into four distinct groups. These clusters were significantly differentiated (p < 0.001) in both a PERMANOVA test and a PCA plot. There was a gradual replacement of the dominant species among these clusters. The most recent cluster (2018–2019) was characterized by rare species dominating the community. This shift in species composition suggests that target taxa may have been overexploited. The total landing also decreased, which may have been a result of climate warming. Furthermore, the presence of alien and warm-water species significantly increased. The fish community structure and composition shift could be attributed to anthropogenic (mismanagement) and natural climatic changes (warming).

Karst regions represent fragile landscapes that are particularly vulnerable to environmental changes. The study aims to assess the soil quality in the karst basin of Ioannina, which is located in the north-western region of Greece. Factor analysis was employed to evaluate the concentrations of trace elements in the soil. Additionally, Geographical Information Systems (GIS) was utilized to visualize the spatial distribution of these trace elements and their potential sources in relation to the local geology and land use. The study findings underscored that most of the karst landscape in the research area is comprised of Quaternary deposits and it is predominantly occupied by agricultural land. The soil displays substantial levels of clay and silt, with noticeably elevated concentration of iron (Fe), manganese (Mn), nickel (Ni), chromium (Cr), lead (Pb), copper (Cu), vanadium (V), and phosphorous (P) compared to the median concentrations observed in European topsoil. The factor analysis is applied to the dataset of elements content in soil to identify the factors controlling their distribution. Factor 1 involves the geological contribution and the adsorption of Fe–Ni–Cr–Pb–V and lithium (Li) into clay minerals. Factor 1 may be termed as “lithogenic factor”. The cultivated land and road network showed a significant correlation with the higher positive loadings of Fe, Mn, Pb and Cu for Factor 2 which may be termed “agricultural-road network factor”. Agricultural activities and cultivated land presented a significant correlation with the higher positive loadings of nitrate (NO3−), nitrite (NO2−), organic matter (OM), ammonium (NH4+) and P for Factor 3 which may be termed as “agricultural” factor. The higher positive loadings of Factor 4 suggest a variation in the mechanical properties of the Quaternary deposits and may be termed as “soil texture factor”. Quaternary deposits and agricultural land exhibit a strong spatial relationship with factor scores of each factor. Combining factor analysis and GIS proved to be an effective method for identifying and confirming the sources of elements content in soil.

Improperly managed wastewater effluent poses environmental and public health risks. BOD evaluation is complicated by wastewater treatment. Using key parameters to estimate BOD in wastewater can improve wastewater management and environmental monitoring. This study proposes a BOD determination method based on the Artificial Neural Networks (ANN) model to combine Chemical Oxygen Demand (COD), Suspended Solids (SS), Total Nitrogen (T-N), Ammonia Nitrogen (NH4-N), and Total Phosphorous (T-P) concentrations in wastewater. Twelve different transfer functions are investigated, including the common Hyperbolic Tangent Sigmoid (HTS), Log-sigmoid (LS), and Linear (Li) functions. This research evaluated 576,000 ANN models while considering the variable random number generator due to the ten alternative ANN configuration parameters. This study proposes a new approach to assessing water resources and wastewater facility performance. It also demonstrates ANN's environmental and educational applications. Based on their RMSE index over the testing datasets and their configuration parameters, twenty ANN architectures are ranked. A BOD prediction equation written in Excel makes testing and applying in real-world applications easier. The developed and proposed ANN-LM 5-8-1 model depicting almost ideal performance metrics proved to be a reliable and helpful tool for scientists, researchers, engineers, and practitioners in water system monitoring and the design phase of wastewater treatment plants.

The main objective of this research was to evaluate the surface water system of Lake Vegoritida (Region of Central Macedonia, Greece). The Driver–Pressure–State–Impact–Response (DPSIR) methodological approach was used. The analysis includes data from three (3) stations monitoring point source pollution and recording the most critical water quality measurement parameters in a time series data analysis from 1983 to 1997. The data will contribute to the analysis and was used to investigate, identify, and evaluate possible sources of chemical and ecological changes recorded in the lake. The artificial neural network (ANN) is a valuable tool for making predictions based on the water quality data set. The findings highlighted the increased concentration of nutrients that contribute to the presence of eutrophic conditions, while their seasonal variability is mainly due to factors, such as water level fluctuations and biological processes in the lake. The above, combined with the critical biotic indicators and factors alongside the reduction in biodiversity, indicated that only the most resistant species survive, confirming the previous finding. In Greece, systematic monitoring and reporting programs have recently been implemented, such as the ECOFRAME scheme and the guidelines proposed by the “Intercalibration Group for Mediterranean Lakes”. The water quality status could be classified as “High”, “High to Good”, and “High to Poor”, respectively, while the overall ecological assessment tends to change to poor conditions. The actions required at an early stage concern the planning of programs and actions that contribute to the sustainable management of land uses and the reduction in point sources of pollution, as well as the reduction of the applied quantities of agrochemicals on the cultivated land in the study area.

The primary goal of this study is to analyze the hydrogeochemical properties and assess the groundwater quality for drinking, domestic, and irrigation purposes in West El Minia, Egypt. Major components were determined in 49 groundwater samples to evaluate water quality in the study area. Principal component analysis (PCA), hierarchical cluster analysis (HCA), geostatistics, and spatial mapping were used to identify the chemical components and processes that influence groundwater quality and highlight areas of health risks. According to the TDS values, about 22% of the groundwater samples are suitable for drinking. Due to the elevated values of hardness in the examined water, none of the water samples are suitable for use in a household. The majority of groundwater samples are acceptable for irrigation based on the sodium adsorption ratio (SAR), residual sodium carbonate (RSC), Kelley ratio (KR), magnesium hazard (MH), and permeability index, and some can be adequately treated. The study indicated that different groundwater characteristics (such as TDS, Na+, K+, HCO3−, Cl−, and SO42−) do not comply with WHO requirements in some regions, which may pose a threat to human health.

Water quality indices (WQIs) are practical and versatile instruments for assessing, organizing, and disseminating information about the overall quality status of surface water bodies. The use of these indices may be beneficial in evaluating aquatic system water quality. The CCME (Canadian Council of Ministers of the Environment) and NSF (National Science Foundation) WQIs were used for the assessment of surface water (depth = 1 m) in Lake Union, Washington State. These WQIs were used in surface water at Lake Union, Seattle. The modified versions of the applied WQIs incorporate a varied number of the investigated parameters. The two WQIs were implemented utilizing specialized, publicly accessible software tools. A comparison of their performance is offered, along with a qualitative assessment of their appropriateness for describing the quality of a surface water body. Practical conclusions were generated and addressed based on the applicability and disadvantages of the evaluated indexes. When compared to the CCME-WQI, it is found that the NSF-WQI is a more robust index that yields a categorization stricter than CCME-WQI.

The composition of sediments and other materials occurring in streams, geochemical processes within the drainage basin, and various land uses are among the main factors influencing stream water composition. Stream sediment and wildfire ash samples were gathered from the area studied. The applied methodology consists of aqua regia and Diethylene-Triamine-Penta-Acetic acid (DTPA) chemical extraction; Cation Exchange Capacity (CEC), pH, and soil organic matter (OM) determination; a Geographic Information System (GIS) database; factor analysis; and determination of the contamination factor (CF) for the assessment of contamination degree. This study aimed to evaluate the elements' content in stream sediments of Kineta and Nea Peramos areas (West Attica, Greece) and investigate any relationship between elements (aqua regia and DTPA extracted) in stream sediment and ash in wildfire and flood-impacted areas. The stream sediments' properties, the bioavailable forms of copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn), and the total content of other potentially toxic elements in wildfire ash samples, are discussed. This research estimated moderate contamination for Fe-DTPA, Mn-DTPA and Zn-DTPA in stream sediments of the study area. Contamination for Cu-DTPA and moderate contamination for Zn-DTPA in the stream sediments of the Nea Peramos area was recorded. Factor analysis results suggested that the contents of Fe-DTPA, Mn-DTPA, Cu-DTPA and Zn-DTPA in the study area's stream sediments may affect the chemistry of stream water.

The Mediterranean countries' coastal-karstic aquifer systems are facing increased pressure due to seawater intrusion and drought impacts. There is a need to understand better karstic systems' functional mechanisms for developing the most appropriate management scenario of water resources in these systems. In this study, the application of Non-Linear Autoregressive neural networks (NAR) on a dataset from mid-1968 to 1994 was deployed for predicting values of discharge flow rates and salinity of Almyros spring (Heraklion-Crete, Greece). Two neural networks were trained for the prediction of the discharge rates and the chloride concentration. The neural networks operated with the Levenberg–Marquardt algorithm's aid and attained a coefficient of determination R = 0.83, and R = 0.86, respectively, indicating a high degree of prediction capacity.

Karst features such as polje are highly vulnerable to natural and anthropogenic pollution. The main objectives of this study were to investigate the soil quality in the Ioannina polje (north-west Greece) concerning arsenic (As) and zinc (Zn), and delineate their origin as well as compare the As and Zn content in soil with criteria recorded in the literature. For this purpose, the geomorphological settings, the land use, and the soil physicochemical properties were mapped and evaluated, including soil texture and concentrations of aqua-regia extractable As and Zn. The concentration of elements was spatially correlated with the land use and the geology of the study area, while screening values were applied to assess land suitability. The results reveal that 72% of the total study area has a very gentle slope. This relief favors urban and agricultural activity. Thus, the urban and agricultural land used cover 92% of the total area. The spatial distribution for As and Zn in the soil of the study area is located on very gentle slopes and is strongly correlated with the geological parent materials and human-induced contamination sources. Arsenic and Zn can be considered enriched in the soil of the area studied. The median topsoil contents (in mg kg−1) for As (agricultural soil 16.0; urban soil 17.8) and Zn (agricultural soil 92.0; urban soil 95.0) are higher compared to the corresponding median values of European topsoils. Land evaluation suitability concerning criteria given from the literature is discussed. The proposed work may be helpful in the project of land use planning and the protection of the natural environment.

The Driver–Pressure–State–Impact–Response (DPSIR) framework is applied for assessing the pressures and impacts on groundwater bodies of two Mediterranean sites (Megara and Oropos–Kalamos basins). The study areas present joint driving forces (drivers) and pressures. The main driving forces in the areas studied mainly include geology, agricultural activities, and urban development, while the main pressures mainly include the weathering of ultramafic rock masses, application of agrochemicals, and groundwater abstractions for irrigation and drinking uses. Hexavalent chromium (Cr+6), chromium total (Crtotal), manganese (Mn), and nitrate (NO3−) contamination of groundwater bodies are attributed to both anthropogenic and lithological sources. Elevated Crtotal (up to 70.3 μg L−1), Mn (up to 87.7 μg L−1), and NO3− (up to 411 mg L−1) contents are recorded for groundwater samples in Megara basin. High Crtotal (up to 34.3 μg L−1), Cr6+ (up to 27.9 μg L−1), Mn (up to 132.5 μg L−1), and NO3− (up to 30 mg L−1) are also observed for groundwater samples in the Oropos–Kalamos basin. The major response actions needed for the management options of groundwater bodies are discussed. Among the proposed remedial measures, the installation of a continuous groundwater monitoring network and the control in the usage of nitrogen fertilizers seems to be the most effective and tangible for immediate action.

Assessing the suitability of urban and agricultural land is essential for planning sustainable urban and agricultural systems. The main objective of this study is to evaluate the suitability of land in Ioannina plain (western Greece) concerning the soil contents of two potentially toxic elements, cadmium (Cd) and cobalt (Co). Geochemical and spatial analysis methods were applied to assess the distribution of Cd and Co in the soil of the Ioannina plain and identify their origin. The primary anthropogenic sources of Cd and Co in the topsoil of the study area can be attributed to traffic emissions, aircraft operations, vehicle crushing and dismantling activities. Element content is compared to international guidelines and screening values. Cadmium and Co concentration in the soil of the study area is well above the European topsoil mean. Thus, the urban and agricultural lands cover the vast majority (92%) of the total area. Cadmium concentration in soil of the study area with a mean (mg kg−1) 1.7 and 2.0 was observed in agricultural and urban land use, respectively. Cobalt content in soil of the area studied with a mean (mg kg−1) 30.8 and 37.1 was recorded in agricultural and urban land use, respectively. Land evaluation suitability by adopting criteria provided from the international literature is discussed.

On the occasion of the July 2018 wildfire in the West Attica region (Kineta area, Geraneia Mountain) this study aimed to the assessment of soil quality in Kineta area and the effect of fire on soil properties and the bioavailable forms of copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn), which is a topic poorly documented. Topsoil (0–5 cm depth) and subsoil (5–25 cm depth) samples were collected from burned sites and unburned control sites two months after the wildfire event. The area is mainly covered by pine trees ( Pinus halepensis ). Statistical analysis and Geographical Information System (GIS) database elaboration proved successful tools for this research. The type of methodology applied in this study consists of Diethylene-Triamine-Penta-Ace-tic acid (DTPA) chemical extraction, pH, Cation Exchange Capacity (CEC), Electric Conductivity (EC) and soil organic matter (OM) evaluation, factor analysis, GIS database and comparison of soil parameters with quality standards and levels given from the literature. Results of this study indicated that wildfires significantly (p < 0.05) increased pH values, as well as, OM, Fe DTPA and Mn DTPA higher contents in topsoil at burned sites than topsoil in unburned locations. This higher availability of elements in the soil may be associated with the addition of ash during a fire. At the same time, relationships between various parameters have been identified from factor analysis and reflect genetic association. A GIS elaboration showed the spatial relationship among high positive factor scores, lithology, Mn-oxides and soil condition (burned or unburned soil). In particular, Zn DTPA contents in Kineta soils constitute a case of lithogenic contamination, while high concentrations of Mn DTPA demonstrate the role of wildfire in enhancing levels of available elements in topsoil.

ABSTRACT Total contents of 36 potentially toxic elements are summarized for agricultural topsoil (n = 12; soil depth = 0–20 cm), subsoil (n = 12; soil depth = 20–40 cm), and representative rock samples collected from a Mediterranean site (Megara Plain, Greece). The five-stage sequential extraction procedure for the geochemical partitioning of cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), and nickel (Ni), proposed by Tessier, was applied to topsoil and subsoil collected from the study area. Soil Cd was highly associated with exchangeable fraction, illustrating high bioavailability of this element. The order of mobility of the elements was as follows: Cd > Cu > Co > Zn > Ni > Cr > Mn. Results from sequential extraction experiments illustrated that the bioavailability of Cu, Co, and Zn is moderate, while Ni, Cr, and Mn presented low bioavailability, indicating that these elements could pose a limited threat to the quality of crops. Cadmium is the chief contamination controlling factor posing moderate potential ecological risk. The contamination sources of the examined elements are discussed.

A 1-year monitoring study is presented on the chemical status of two surface water reservoirs in a decentralized Mediterranean island. Water samples were collected at varying depths in the two surface water reservoirs and different seasons between November 2015 and September 2016, covering both wet and dry periods of the year. Samples were analyzed in order to determine major chemical parameters and priority substances based on the EU Water Framework Directive (2000/60/EC) and the latest revision of the Priority Substances Policy Directive (2013/39/EU). Tested parameters in both reservoirs did not exceed the set limits. Increased pollutant concentrations were observed in the bottom samples. More than 200 pesticide active substances were determined but none of them was above the parametric trigger value (0.1 μg L−1). Toxic metals were not detected in the examined water samples, whereas the relatively high concentrations of Mn and Cu in the bottom samples are mainly attributed to geogenic background concentrations. Based on the results of the present study, it can be concluded that the chemical situation of both water reservoirs is considered acceptable; however, continuous monitoring should be implemented in the area.

Rocks and sediments are non-anthropogenic sources of elements contamination. In this study, a series of potentially toxic elements were quantified in rocks and sediments of the Oropos-Kalamos basin. Only As, Hg, Pb, and Sb contents, in all the examined rocks and sediments, were higher than the levels given in international literature. Concentration of the elements As, Cr, Hg, Mo, Ni, and U is highly elevated in the lignite compared to crustal element averages. The enrichment of Cr and Ni in the lignite can be attributed to the known ultramafic rock masses surrounding the basin, while enrichment of As, Hg, Mo, Sb, and U is associated with the past geothermal activity of the Upper Miocene (about 15 million years ago). Nickel and Cr were transported into the lignite deposition basin by rivers and streams draining ultramafic rock bodies. The results of this study imply the natural source of Cr3+ and Cr6+ contamination of the Oropos-Kalamos groundwater, since high Cr contents were also recorded in the lignite (212.3 mg kg−1), chromiferous iron ore occurrences (256.6 mg kg−1), and alluvial deposits (212.5 mg kg−1), indicating Cr leaching and transportation to the depositional basin dating from the Upper Miocene age.

Stream sediment samples were collected from Arachthos River, Arachthos–Vovos Artificial Channels, Louros Artificial Channels, Louros River and Vovos River, which are located in Arta plain (western Hellas). The samples were taken in order to determine the spatial distribution of selected elements (Co, Cr, Cu, Fe, Li, Mn, Ni, Pb, Sr, V and Zn), and to evaluate the geogenic and anthropogenic factors controlling the distribution of elements in sediments. The methodology applied in this study includes geomorphological analysis, chemical analysis, factor analysis and comparison of element contents with other data sets. The weathering materials, derived from the Arachthos River's drainage basin, contribute the high element contents in the sediments of the Arta plain. The high element contents may be related with the very gentle slope of the area and the long length of artificial channels. Interpretation of factor analysis results points to geogenic (Fe-oxides, calcareous rocks with phosphorite intercalations, ophiolite fragments within deltaic deposits) and possibly anthropogenic contamination sources (intensive agricultural and farming practices), which control the element distribution in the stream sediments.

In this study, hydrochemical analysis, statistical analysis and GIS database have been successfully used to explain the main factors and mechanisms controlling the distribution of major and trace elements in groundwater. The groundwater of Megara basin is subject to intense exploitation to accommodate all the water demands of this agricultural area. Water quality data obtained from 58 sampling sites of the Megara basin, aims to describe groundwater quality in relation to geology and anthropogenic activities. Factor analysis revealed that four factors accounted for 79.96% of the total data variability. The contribution of each factor at sampling sites was calculated. Evaluation of water samples by comparing quality standards and levels recorded in the literature for both drinking and irrigation uses is discussed.