Distribution Of Groundwater Quality Parameters Research Articles

Assessing Groundwater Quality and Diagnosing Nitrate Pollution in the Sidi Allal Region: A GIS-Based Approach Utilizing the Groundwater Pollution Index

Groundwater is a critical resource for various human activities, yet it faces contamination risks from agricultural, industrial, and domestic sources. This study aimed to evaluate groundwater in Morocco’s Sidi Allal region using the groundwater pollution index (GPI) and diagnose nitrate pollution. The study included 45 groundwater wells from the study area, and physicochemical parameters such as pH, electrical conductivity, cations, and anions were examined in the laboratory. The geographic information system (GIS) was used to determine the spatial distribution of groundwater quality parameters. The groundwater pollution index and nitrate pollution index (NPI) were determined. The inverse distance weighting method (IDW) was used to create a spatial distribution map. The results indicated that the calculated GPI values ranged from 0.856 to 7.416, with an average of 2.06. About 40% of groundwater samples were highly polluted and unsuitable for drinking. The NPI values ranged between −0.74 and 10.5, with an average of 5.1. About 64% of the total groundwater samples were considered highly polluted according to the NPI classification, suggesting that the groundwater was unsuitable for drinking purposes. The spatial distribution map revealed the availability of appropriate groundwater in the central area of the study area and inappropriate groundwater near the Esbou River and Nassour Canal. The findings of this study revealed high concentrations of nitrates in groundwater samples in the central part of the study area, indicating that this increase in nitrates may be due to intensive use of nitrogen fertilizers in agricultural activities and sewage waste.

Geospatial analysis of groundwater quality using GIS: A case study of Ahafo Kenyasi, Ghana

The exploitation and sustainable use of groundwater has received much attention with the sudden decline in quantity and quality of surface water. Knowledge on the current status of the physico-chemical parameters of groundwater becomes important in ensuring the sustainable use of the resource. This study used Geographic Information System (GIS) to assess groundwater quality in Ahafo-Kenyasi with particular focus on determining the spatial distribution of groundwater quality parameters and also produce groundwater quality map of the area. Physico-chemical analyses of groundwater quality parameters were made after collection of water samples from 24 community boreholes. The results of analysis carried out showed the following concentration ranges: pH (5.12-6.54), EC (71.6-952μS/cm), TDS (35.08-465.59mg/l), Turbidity (0-6.25NTU), Ammonia (0.01-0.61mg/l), Nitrate (0.1-4.12mg/l), Sulphate (1-65.5mg/l). All the samples analysed were above the guidelines set by World Health Organization (WHO, 2011) except for pH and Turbidity. Spatial distribution maps of the individual water quality parameters were developed using kriging interpolation technique and accepted based on the prediction performances of Stable, Exponential, K-Bessel semivariogram models. Overall water quality of the study area was assessed using Water Quality Index (WQI). The results showed that groundwater quality in the area decreases from north-western to south-eastern. However, groundwater from Ahafo-Kenyasi is good for domestic purposes.

Spatial distribution of Groundwater quality assessment using Water Quality Index and GIS techniques in Thanjavur Taluk, Thanjavur District, Tamil Nadu, India

Assessment of groundwater quality is of utmost importance to ensure sustainable use of water. Since the availability of water, irrespective of quantity and quality, varies from area to area in Thanjavur taluk. The present paper attempts to determine the spatial distribution of groundwater quality parameters and identify locations with the best quality for drinking and irrigation in the study area using GIS and WQI. Using IDW interpolation methods with ArcGIS 10.8, the spatial distribution maps of physical parameters, anions, cations, WQI, and irrigations indices have been generated. Piper pilot shows that Ca-Mg-Cl (mixed), Na-Cl, Ca-Cl, and Ca–Mg–HCO3 water types are found in the study area. Using a water quality index with a rating scale, 42.85%, 28.57%, and 14.3% of groundwater samples are fit, good, and very poor for drinking purposes, respectively. The obtained results of higher SAR, RSC, Na% show that 75% of groundwater samples are perfectly fit for irrigation purposes due to the long residence time of water, dissolution of minerals from lithological composition, and the addition of chemical fertilizers. The results of groundwater quality analysis have been used to suggest models for assessing water quality. The present study ascertained that the area's groundwater must be treated prior to consumption and protected from the perils of contamination.

Evaluation of some groundwater quality parameters using geostatistics in the urban coastal aquifer of Bosaso plain, Somalia

Groundwater is a major drinking water resource in arid coastal regions. The groundwater quality of Bosaso city experienced degradation due to rapid urbanization and industrialization. This study was carried out to delineate the spatial distribution of groundwater quality parameters and evaluate groundwater suitability for drinking and irrigation uses. The groundwater samples were collected from Bosaso Plain to determine the pH, electrical conductivity (EC), total dissolved solids (TDS), and sodium and chloride concentrations. To categorize water quality for irrigation purposes, sodium adsorption ratio (SAR) was calculated. Ordinary kriging procedure was performed in order to map the spatial distribution of groundwater quality parameters. The interpretation of laboratory analysis results revealed that the most of groundwater wells in the study area is unsafe for drinking purposes due to high salinity, except for the central area (Biyo Kulule). In terms of irrigation uses, the minor area may be under the risk of alkalinity or sodium hazard. However, all groundwater supply points are not suitable for irrigation due to the salinization risk and can be only used to irrigate high salt-tolerant crops. The final maps show that the groundwater quality decreases from southeast to the north of the plain. This indicates that the groundwater is probably subjected to the seawater intrusion. In this regard, the implementation of a groundwater monitoring program is necessary to achieve concrete results. Nevertheless, the most suitable groundwater quality is found to be at the central part of the Bosaso plain.

Factors Controlling the Spatial Distribution and Temporal Trend of Nationwide Groundwater Quality in Korea

Factors controlling the spatial distribution and temporal trend of groundwater quality at a national scale are important to investigate for sustaining livelihood and ecological balance. This study evaluated groundwater quality data for 12 parameters (n = 6405 for each parameter), collected from 97 groundwater monitoring stations (=289 monitoring wells) for ten years. Spatial distribution of groundwater quality parameters varied through the regional scale. Six parameters: T, EC, Ca2+, Mg2+, HCO3−, and Cl− were having dominant increasing trend, remaining pH, Eh, Na+, K+, SO42−, and NO3− showed a dominant decreasing trend over time. Among land use types, the upland fields had the highest mean of groundwater NO3− (22.2 mg/L), confirming plenty of application of fertilizers (5–10 kg/a more than standard) to upland fields. Means of groundwater Cl− and Na+ (705.3 and 298.4 mg/L, respectively) in the residential areas are greater than those in other land use types by 408–685.9, 154.3–274.2 mg/L, respectively. Agricultural activities were the main controlling factor of groundwater NO3− contamination in rural areas, domestic activities were responsible for groundwater Cl− and Na+ in urban areas, and seawater intrusion was controlling groundwater Cl− in coastal areas (within 10 km from sea). Groundwater hydrochemistry was controlled by the mechanism of geogenic rock and evaporation dominance. The rock dominance mechanism indicated that groundwater was interacting with rocks and resulted in groundwater chemistry. The findings of this study showed that groundwater was mainly contaminated by anthropogenic factors in some rural and residential areas. Effective measures by government authorities are needed to improve the groundwater quality.

Spatializing Groundwater Quality Parameters and Their Impacts on Land Value in Khushab City, Punjab, Pakistan

This research was designed to examine the spatial variation in land value in response to ground water qualityin Khushab city, Punjab Pakistan. There were four Physical and five chemical parameters such as pH, ElectricConductivity (EC), Calcium (Ca), hardness, Magnesium (Mg), Total Dissolved Solids (TDS) concentration, taste, colorand odor were tested for groundwater quality appraisal in the study area. There were one hundred water samplescollected from different wells in the study area. Thereafter, the water quality parameters were processed in ArcGIS foranalyzing spatial distribution of groundwater quality parameters by using interpolation and geostatistical tools. It wasfound that all the groundwater parameters were higher than the permissible limit by WHO except pH concentration. Itwas further revealed that the ground water was unsafe for drinking and domestic purpose. Variation in land price wasalso studied with special reference to ground water quality. It was concluded that the groundwater quality has asignificant effect on land value in the study area. The deteriorated groundwater quality was proved to be a potentdeterminant for decreasing land price in the study area.

Spatializing Groundwater Quality Parameters and Their Impacts on Land Value in Khushab City, Punjab, Pakistan

This research was designed to examine the spatial variation in land value in response to ground water qualityin Khushab city, Punjab Pakistan. There were four Physical and five chemical parameters such as pH, ElectricConductivity (EC), Calcium (Ca), hardness, Magnesium (Mg), Total Dissolved Solids (TDS) concentration, taste, colorand odor were tested for groundwater quality appraisal in the study area. There were one hundred water samplescollected from different wells in the study area. Thereafter, the water quality parameters were processed in ArcGIS foranalyzing spatial distribution of groundwater quality parameters by using interpolation and geostatistical tools. It wasfound that all the groundwater parameters were higher than the permissible limit by WHO except pH concentration. Itwas further revealed that the ground water was unsafe for drinking and domestic purpose. Variation in land price wasalso studied with special reference to ground water quality. It was concluded that the groundwater quality has asignificant effect on land value in the study area. The deteriorated groundwater quality was proved to be a potentdeterminant for decreasing land price in the study area.

Geospatial Distributions of Groundwater Quality in Gedaref State Using Geographic Information System (GIS) and Drinking Water Quality Index (DWQI).

The observation of groundwater quality elements is essential for understanding the classification and distribution of drinking water. Geographic Information System (GIS) and remote sensing (RS), are intensive tools for the performance and analysis of spatial datum associated with groundwater sources control. In this study, groundwater quality parameters were observed in three different aquifers including: sandstone, alluvium and basalt. These aquifers are the primary source of national drinking water and partly for agricultural activity in El Faw, El Raha (Fw-Rh), El Qalabat and El Quresha (Qa-Qu) localities in the southern part of Gedaref State in eastern Sudan. The aquifers have been overworked intensively as the main source of indigenous water supply in the study area. The interpolation methods were used to demonstrate the facies pattern and Drinking Water Quality Index (DWQI) of the groundwater in the research area. The GIS interpolation tool was used to obtain the spatial distribution of groundwater quality parameters and DWQI in the area. Forty samples were assembled and investigated for the analysis of major cations and anions. The groundwater in this research is controlled by sodium and bicarbonate ions that defined the composition of the water type to be Na HCO3. However, from the plots of piper diagram; the samples result revealed (40%) Na-Mg-HCO3 and (35%) Na-HCO3 water types. The outcome of the analysis reveals that several groundwater samples have been found to be suitable for drinking purposes in Fa-Rh and Qa-Qu areas.

Groundwater quality mapping of Yogyakarta City, Sleman, Kulonprogo and Bantul regency area of Yogyakarta Province

The groundwater quality is equally important as that of quantity. GIS is a powerful tool for representation and analysis of spatial information related to water resources. To attempt this goal, samples were analyzed for various physico-chemical and bacterial parameters such as pH, Electrical Conductivity (EC), nitrate, Fe, E. coli, etc have been estimated for all the sampling locations. The spatial variation maps of these groundwater quality parameters were derived and integrated through GIS. An interpolation technique inverse distance weighting was used to obtain the spatial distribution of groundwater quality parameters. The final map classified the groundwater quality in the study area. The results of this research show that groundwater contamination are occurred and the development of the management strategies for the aquifer system is vitally necessary.

Spatial analysis of groundwater quality mapping in hard rock area in the Akola and Buldhana districts of Maharashtra, India

The study of groundwater quality parameters is most essential for irrigation and drinking water, and its quality is a serious problem around the study area. The spatial analysis of groundwater quality mapping is required and stimulated us to undertake a systematic work of groundwater quality parameters for suitable water exploration of crops and drinking purposes from bore wells and open wells in basaltic hard rock area. A detailed study of physico-chemical parameters composition of groundwater was performed from groundwater quality data of post-monsoon (December) in the year of 2013. The groundwater quality data were collected from 35 wells samples randomly distributed in area. GIS is a powerful tool for representation and analysis of spatial information related to groundwater resources management. To achieve this aim, the groundwater quality samples were analysed for the preparation of groundwater quality maps such as pH, electrical conductivity, TDS, Cl and Mg. The groundwater quality parameters were analysed for all the sampling locations using IWD interpolation techniques. In this study, groundwater quality values observed are minimum and maximum values of pH (6.2–8 on scale), electrical conductivity (348–1598 S/cm), total dissolved solids (268.32–707.95 mg/l), carbonate (0–30 mg/l), bicarbonate (0.9–58.9 mg/l), chloride (1.15–28.36 mg/l), sulphate (17.4–105 mg/l), nitrate (0.4–6.0 mg/l), calcium (2.35–7.24 mg/l), magnesium (2.88–3.73 mg/l), sodium (0.57–3.31 mg/l), potassium (0.26–1.2 mg/l), sulphate (0.5–4.64 mg/l), bicarbonate+ carbonate (1.07–11.16 mg/l) and carbonate (0–0.79 mg/l) in hard rock area. The spatial variation maps were derived and integrated through ARC GIS 10.3 software. The interpolation tool was used to obtain the spatial distribution of groundwater quality parameters in the basaltic hard rock area. Therefore, the result of groundwater analysis of large number of groundwater samples has been found to be suitable for drinking and irrigation purposes in the basaltic hard rock area.

GIS-Based Spatial Distribution of Groundwater Quality and Regional Suitability Evaluation for Drinking Water

Hydrochemistry mapping of groundwater is one of the important aspects of water resources management of an area based on usages such as drinking water or irrigation, and their quality requirement. Such mapping could lead to optimal utilization and protection from quality deterioration. In this paper, a geospatial based water quality index is developed for preparing water quality class suitability map. The aim of this study is to provide an overview of the spatial variation of groundwater quality parameters, i.e., Fluoride (F_), Nitrate (NO3 _), Chloride (Cl_), Total Dissolved Solids (TDS), pH and Total Hardness (TH) in the Khushkhera - Bhiwadi - Neemrana Investment Region (KBNIR). Groundwater samples were collected from 14 locations, tested in the laboratory and were analyzed using Geographical Information Systems (GIS) techniques. Geospatial analyst tools were used to generate various thematic maps, and interpolation techniques were applied to identify the spatial distribution of groundwater quality parameters. Groundwater quality was analyzed in detail and compared with BIS and WHO water quality standards. Multivariate statistical techniques, such as Correlation Matrix Analysis and Principal Component Analysis (PCA) were carried out. The correlation coefficient showed TDS highly correlated with chloride (r = 0.725), and a negative correlation (r = −0.656) between pH and nitrate. It was observed that 36.02% of the populated area depends on excellent quality groundwater and 23.56% on good quality groundwater, while poor and moderately poor quality groundwater is available for respectively 6.26% and 34.16% of the populated area. Also, only 65.88% of the total geographical area within the KBNIR region is hydrochemically suitable for drinking purposes. Attempts are also made to compare these results with PCA results.

Temporal and spatial variation of chemical parameter concentration in drinking water resources of Bandar-e Gaz City using Geographic Information System

One of the serious challenges in ensuring and promoting community health is gradual increase in contamination levels of drinking water of communities across the world. The purposes of this study were (1) to evaluate the chemical quality of groundwater in the Bandar-e Gaz city and (2) to determine spatial distribution of groundwater quality parameters (total hardness (TH), chloride, nitrate and fluoride concentrations, and (3) mapping the quality of groundwater using Geographical Information System (GIS) software. In this study 20 groundwater samples were collected from 5 wells in two successive 2010–2011, in the rainy and dry seasons. Sample preparation and analysis, according to standard methods were done. Based on the findings of this study, it can be expressed that the average concentration chloride and nitrate parameters in Bandar-e Gaz drinking water is within the 1053 standard limit in Iran, except fluoride content is lower than the standard and hardness was high in majority of water sample groundwater. According to the zoning maps of groundwater, in the dry season’s nitrate and hardness concentration is greater than rainy seasonal. The data showed falling and rising trend in CL concentrations, respectively. This study indicated that all parameter within the standard except fluoride then, its necessity to addition fluoride in that’s regions population food chain and drinking water. Management of the utilization and protection greed underground waters should be as a basic principle in the planning Bandar-e Gaz city. © 2017 Desalination Publications. All rights reserved.

Evaluation of groundwater quality using a GIS-MCDA-based model: a case study in Aksaray, Turkey

Evaluation of water resources and the protection of these resources from environmental pollutants is a difficult and complex process. In this study, a development of model to estimate the water quality and identify the most suitable regions based on good water quality was aimed. For this purpose, 40 water samples were taken through water wells in Aksaray region of Turkey. A groundwater quality index (AWQI) based on water chemistry data has been developed to assessment the groundwater quality using the techniques of the multi-criteria decision analysis. Based on this index, four suitability classes were defined as excellent, good, permissible and unsuitable. Kriging method was used to determine the spatial distribution of groundwater quality parameters in the study area. For each map, different semivariogram models were tested by cross-validation and the best model was selected. The exponential model having a minimum standard error was selected the most suitable model for deriving water quality maps. The areas that are excellent for groundwater quality are concentrated in the northeastern and southeastern parts of the region where the AWQI-II scores were greater than 0.9. This study provides general information on how to determine the spatial distribution of the groundwater quality and identify the performance scores of criteria affecting water quality in inland aquifers.

Accessing groundwater quality in lower part of Nagapattinam district, Southern India: using hydrogeochemistry and GIS interpolation techniques

The aim of this present study was to evaluate groundwater quality in the lower part of Nagapattinam district, Tamil Nadu, Southern India. A detailed geochemical study of groundwater region is described, and the origin of the chemical composition of groundwater has been qualitatively evaluated, using observations over a period of two seasons premonsoon (June) and monsoon (November) in the year of 2010. To attempt this goal, samples were analysed for various physico-chemical parameters such as temperature, pH, salinity, Na+, Ca2+, K+, Mg2+, Cl−, HCO3− and SO42−. The abundance of major cations concentration in groundwater is as Na > Ca > Mg > K, while that of anions is Cl > SO4 > HCO3. The Piper trilinear diagram indicates Ca–Cl2 facies, and according to USSL diagram, most of the sample exhibits high salinity hazard (C3S1) type in both seasons. It indicates that high salinity (C3) and low sodium (S1) are moderately suitable for irrigation purposes. Gibbs boomerang exhibits most of the samples mainly controlled by evaporation and weathering process sector in both seasons. Irrigation status of the groundwater samples indicates that it was moderately suitable for agricultural purpose. ArcGIS 9.3 software was used for the generation of various thematic maps and the final groundwater quality map. An interpolation technique inverse distance weighting was used to obtain the spatial distribution of groundwater quality parameters. The final map classified the ground quality in the study area. The results of this research show that the development of the management strategies for the aquifer system is vitally necessary.

Groundwater quality assessment using the Water Quality Index and GIS in Saveh-Nobaran aquifer, Iran

Groundwater is the most important natural resource used for drinking by many people around the world, especially in arid and semi-arid areas. The resource cannot be optimally used and sustained unless the quality of groundwater is assessed. Saveh-Nobaran aquifer in Iran is the most important groundwater aquiferous system in the region which is considered a major source for drinking and irrigation. The main objective of this study is to understand the groundwater quality status of Saveh-Nobaran aquifer, followed by attempts to investigate the spatial distribution of groundwater quality parameters to identify places with the best quality for drinking consume within the study area. For this purpose, a set of original data, as yet unpublished, is presented. This paper provides an important contribution for understanding relationship between land use and groundwater quality, and also groundwater depth and groundwater quality. This goal has been achieved with the combined use of the Water Quality Index (WQI) and a geographical information system (GIS). A total of 58 groundwater samples were collected and analyzed for major cations and anions. Spatial distribution maps of pH, TDS, EC, TH, Cl, HCO, SO4, Ca, Mg, Na and K have been created using the kriging method in a GIS environment. From the WQI assessment, over 65 % of the water samples fall within the ‘‘Poor’’, ‘‘Very poor’’ and “unsuitable for drinking” categories, suggesting that groundwater from the center and north-east of the Saveh-Nobaran aquifer is unsuitable for drinking purposes. This research and its results have shown the great combination use of GIS and WQI in assessing groundwater quality. Having a clear view of the geographic areas of groundwater quality, decision makers can plan better for the operation and maintenance of groundwater resources.

Assessment of Groundwater Chemical Quality, Using Inverse Distance Weighted Method

An interpolation technique, ordinary Inverse Distance Weighted (IDW), was used to obtain the spatial distribution of groundwater quality parameters in Damghan plain of Iran. According to Scofield guidelines for TDS value, 60% of the water samples were harmful for irrigation purposes. Regarding to EC parameter, more than 60% of studied area was laid in bad range for irrigation purposes. The most dominant anion was Cl - and 10% of water samples showed a very hazardous class. According to Doneen guidelines for chloride value, 100% of collected water from the aquifer had slight to moderate problems for irrigation water purposes. The predominant cations in Damghan plain aquifer were according to Na + > Ca ++ > Mg ++ > K + . Sodium ion was the dominant cation and regarding to Na + content guidelines, almost all groundwater samples had problem for foliar application. Calcium ion distribution was within usual range. The magnesium ion concentration is generally lower than sodium and calcium. The majority of the samples showed Mg ++ amount within usual range. Also K + value ranged from 0.1 to 0.23 meq/L and all the water samples had potassium values within the permissible limit. Based on SAR criterion 80 % of collected water had slight to moderate problems. The SSP values were found from 2.87 to 6.87%. According to SAR value, thirty percent of ground water samples were doubtful class. The estimated amounts of RSC were ranged from 0.4-2 and based on RSC criterion, twenty percent of groundwater samples had slight to moderate problems Normal 0 false false false EN-US X-NONE AR-SA /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Calibri","sans-serif"; mso-bidi-language:AR-SA;}

Microtopography as a Driving Mechanism for Ecohydrological Processes in Shallow Groundwater Systems

Microtopography can have a large effect on flow processes at the soil surface and the composition of soil water. Microtopography is often represented by a roughness parameter in hydrological models. In areas without a strong topographical gradient, microtopography may be underestimated when accumulated in a single parameter, especially in shallow groundwater systems. This study reviews the intricate relationships between microtopography, surface runoff, and ecohydrology in systems featuring shallow water tables. We specifically focus on relations between microtopography and runoff, impact of microtopography on response times of shallow groundwater ecosystems, and microtopography and spatial distribution of groundwater quality parameters and site factors. We advocate the use of microtopography in modeling approaches by examples that feature typical ecosystems with shallow groundwater under influence of microtopography. With a simple modeling approach, we show how microtopography could add flexibility to the acrotelm–catotelm concept in raised bog hydrology. The classic acrotelm–catotelm concept hinders progress in understanding small scale hydrological variations and other ecohydrological relations. Furthermore, we illustrate possible self-organization properties of wetlands. Finally, we show how microtopography and surface runoff affect the mixing of water with different chemical signatures, resulting in variations of the occurrence of plant species.

Use of geographical information system and water quality index to assess groundwater quality in El Khairat deep aquifer (Enfidha, Central East Tunisia)

Groundwater is the most important natural resource used for drinking by many people around the world, especially in rural areas. In Tunisia, since the quantity and the quality of water available for different uses is variable from one place to another, groundwater quality in El Khairat deep aquifer was evaluated for its suitability for drinking purposes. To this end, an attempt has been made for the first time in order to determine spatial distribution of groundwater quality parameters and to identify places with the best quality for drinking within the study area based on: (1) an integrated analysis of physical–chemical parameters, (2) use of Geographical Information System, and (3) Water Quality Index (WQI) calculation. The physical–chemical results were compared with the World Health Organization (WHO) standards for drinking and public health, in order to have an overview of the present groundwater quality. According to the overall assessment of the basin, almost all the parameters analyzed are above the desirable limits of WHO. Using GIS contouring methods with Arcview 3.2a, spatial distribution maps of pH, TDS, EC, TH, Cl, HCO3, SO4, NO3, Ca, Mg, Na, and K have been created. The spatial analysis of groundwater quality patterns of the study area shows that the TDS value increases from north-west to south-east following the general trend of the Khairat aquifer flow direction. The spatial distribution map of TH shows that a majority of the groundwater samples falls in the very hard category. WQI was used to assess the suitability of groundwater from the study area for human consumption. From the WQI assessment, over 82% of the water samples fall within the “Poor” and “Very poor” categories, suggesting that groundwater from the south-eastern of the El Khairat deep aquifer is unsuitable for drinking purposes.

Groundwater quality mapping in urban groundwater using GIS

Konya City, located in the central part of Turkey, has grown and urbanized rapidly. A large amount of the water requirement of Konya City is supplied from groundwater. The quality of this groundwater was determined by taking samples from 177 of the wells within the study area. The purposes of this investigation were (1) to provide an overview of present groundwater quality and (2) to determine spatial distribution of groundwater quality parameters such as pH, electrical conductivity, Cl-, SO4(-2), hardness, and NO3- concentrations, and (3) to map groundwater quality in the study area by using GIS and Geostatistics techniques. ArcGIS 9.0 and ArcGIS Geostatistical Analyst were used for generation of various thematic maps and ArcGIS Spatial Analyst to produce the final groundwater quality map. An interpolation technique, ordinary kriging, was used to obtain the spatial distribution of groundwater quality parameters. The final map shows that the southwest of the city has optimum groundwater quality, and, in general, the groundwater quality decreases south to north of the city; 5.03% (21.51 km2) of the total study area is classified to be at the optimum groundwater quality level.