An appraisal of groundwater quality for drinking and irrigation purposes in southern part of Bathinda district of Punjab, northwest India

Groundwater is being used for drinking and irrigation purposes in the agricultural dominated Indian state of Punjab. Fifty-six groundwater samples were collected from Bathinda, a south-western district of Punjab, during the pre-monsoon (March 2010) and post-monsoon (October 2011) seasons. These samples were tested for major cations, anions and contaminants. Various classification systems were used to study the groundwater quality with respect to drinking as well as irrigation purposes. Total dissolved solids (TDS) and total hardness (TH) are generally used to determine the suitability of groundwater for drinking purpose. Considering TDS as a parameter, 54 and 57 % groundwater samples were found to be unsuitable for use during the pre- and post-monsoon seasons. A wide range of TH values were observed in the pre-monsoon and post-monsoon waters samples (mean 250 and 270 mgL^?1). About 75 % of pre-monsoon and 79 % of post-monsoon samples exceeded the maximum permissible limit (MPL) of TH (150 mg L^?1) proposed by WHO. In terms of contaminant ions, 40 % and 55 % of the pre- and post-monsoon water samples were unfit for drinking purposes w.r.t. fluoride (MPL 1.5 mg F L^?1), 29 and 36 % were unfit w.r.t arsenic (MPL 10 μg L^?1) and 33 and 45 % were unfit w.r.t nitrate (MPL 45 mg NO₃ ^? L^?1), respectively. To determine the suitability of groundwater of Bathinda for irrigation purpose, three classification systems proposed by different research workers were used. The parameters electrical conductivity (EC), sodium adsorption ratio, and residual sodium carbonate (RSC) were calculated on the basis of chemical data. Considering EC and RSC together, 32 % samples collected during pre-monsoon season were fit, 19 % were marginal and 49 % were unfit for use. However, during post-monsoon, samples fit for irrigation decreased to 17 % and samples unfit for irrigation increased to 70 %. Increases in the percentage of unfit samples for irrigation after monsoon indicates addition of salts along with the rain water percolated into the groundwater. The other two classification systems, i.e. US Salinity diagram and Wilcox diagram also showed the similar results.     

Suitability assessment of shallow and deep groundwaters for drinking and irrigation use in the El Khairat aquifer (Enfidha, Tunisian Sahel)

The El Khairat aquifer is an important groundwater aquiferous system, which is considered a major source for drinking and irrigation water in Enfidha in Tunisian Sahel. The analysis of groundwater chemical characteristics provides much important information useful in water resources management. Assessing the water quality status for special use is the main objective of any water monitoring studies. An attempt has been made for the first time in this region to appreciate the quality and/or the suitability of shallow and deep groundwater for drinking and irrigation. In order to attend this objective, a total of 35 representative water samples were collected during February 2007 from both boreholes (17) and wells (18); and analyzed for the major cations (sodium, calcium, magnesium and potassium) and anions (chloride, sulphate, bicarbonate, and nitrate) along with various physical and chemical parameters (temperature, pH, total dissolved salts, and electrical conductivity). Based on the physico-chemical analyses, irrigation quality parameters like sodium absorption ratio (SAR), residual sodium carbonate (RSC), percentage of sodium (Na%), and permeability index (PI) were calculated. In addition to this, iso-concentration maps were constructed using the geographic information system to delineate spatial variation of qualitative parameters of groundwater samples. The correlation of the analytical data has been attempted by plotting different graphical representations such as Piper, Wilcox, and US Salinity Laboratory for the classification of water. The suitability of the water from the groundwater sources for drinking and irrigation purposes was evaluated by comparing the values of different water quality parameters with World Health Organization guideline values for drinking water. A preliminary hydrochemical characterization shows that most of the groundwater samples fall in the field of calcium–magnesium–chloride–sulphate type of water. Majority of the samples are not suitable for drinking purposes and far from drinking water standards. The high EC value and the percentage of Na in most of the groundwater render it unsuitable for irrigation. Wilcox classification suggested that around 50% of both deep and shallow groundwater samples are unsuitable for irrigation. According to the US Salinity Classification, most of the groundwater is unsuitable for irrigation unless special measures are adopted.     

Hydrogeochemical parameters for assessment of groundwater quality in a river sub-basin

Hydrogeochemical studies were carried out in the Ghataprabha River sub-basin to assess the quality and suitability of groundwater for domestic and irrigation purposes. In the present study, an integrated, geophysical and chemical investigation was carried out in the basaltic terrain. Groundwater samples were collected covering the entire major hydrogeological environment for one hydrological cycle. Comparison of the groundwater quality in relation to drinking water quality standards proves that most of the water samples are not suitable for drinking. Chemical indices such as sodium percentage, sodium adsorption ratio and chloroalkaline indices used for evaluating the water quality for irrigation suggest that the majority of the groundwater samples were good for irrigation. Positive values of 74% of groundwater samples indicated the absence of base exchange reaction (chloroalkaline disequilibrium) and negative ratio of 26% samples indicated a base exchange reaction (chloroalkaline equilibrium). Resistivity tomography studies revealed that the high concentration of total dissolved solids, chloride and sodium were due to the local anthropogenic activities and weathering of basalt rocks.     

Assessment of water quality for drinking and irrigation purposes: a case study of Başköy springs (Ağlasun/Burdur/Turkey)

It is important to know the quality of water resources for drinking, domestic and irrigation in the rural area. Because, in recent times, there has been increased demand for water due to population growth and intense agricultural activities, so, hydrogeochemical investigations come into prominence for the groundwater use. The purpose of this paper is to evaluate water quality of Ba?köy springs for both drinking and irrigation purposes. The geochemical processes and quality of springs were followed as seasonal in the study area. In view of geochemical classification, springs are Ca-Mg-HCO₃ water type for both seasons. Comparison of geochemical data shows that majority of the spring samples are suitable for drinking water. On the other hand, chemical indexes of springs with various classifications were calculated for irrigation purposes. According to the classifications (electrical conductivity, total dissolved solids, total hardness, salinity hazard, percent sodium, sodium adsorption ratio, residual sodium carbonate, residual sodium bicarbonate, permeability index, potential salinity, soluble sodium percentage, magnesium ratio, and Kelly’s ratio), Ba?köy springs are suitable for irrigation purposes. However, water quality of Çaygözü spring is different the other springs due to the high electrical conductivity and total dissolved solids. Also, groundwater mineralization processes and rock–water interaction are controlled with bivariate diagrams of major elements.     

Evaluation of groundwater quality for irrigation and drinking using GIS and geostatistics in a peri-urban area of Delhi, India

Intensive agriculture by indiscriminate use of agrochemicals, sewage water, and polluted drain water has posed a serious threat to groundwater quality in some peri-urban areas of Delhi like Najafgarh block. The objective of the study was to determine the groundwater quality and to map their spatial variation in terms of suitability for irrigation and drinking purpose. Ordinary kriging method was used for preparation of thematic maps of groundwater quality parameters such as electrical conductivity, sodium adsorption ratio, bicarbonate, magnesium/calcium ratio, total dissolved solids, chloride, nitrate and hardness. Exponential semivariogram model was best fitted for all quality parameters except chloride and hardness, where spherical model fitted best. Pollution level was highest at south and south-eastern part of the study area. Better quality groundwater may be expected at the northern and western part. High salinity was due to high chloride concentration in the groundwater. Nitrate pollution level was found to be very alarming and need immediate interventions. High dissolved solids and hardness made the groundwater unsuitable for drinking. There were negligible sodium and bicarbonate hazard in the study area. The groundwater quality index was devised to analyse the combined impact of different quality parameters on irrigation and drinking purposes. The irrigation water quality index and drinking water quality index distribution maps delineated an area of 47.29 and 6.54 km² suitable for irrigation and drinking, respectively. These safe zones were found as a small strip along the northern boundary and a very small pocket at the western side of the study area.     

Suitability assessment of deep groundwater for drinking and irrigation use in the Djeffara aquifers (Northern Gabes,south-eastern Tunisia)

The multilayered Djeffara aquifer system, south-eastern Tunisia, has been intensively used as a primary source to meet the growing needs of the various sectors (drinking, agricultural and industrial purposes). The analysis of groundwater chemical characteristics provides much important information useful in water resources management. Detailed knowledge of the geochemical evolution of groundwater and assessing the water quality status for special use are the main objective of any water monitoring study. An attempt has been made for the first time in this region to characterize aquifer behavior and appreciate the quality and/or the suitability of groundwater for drinking and irrigation purposes. In order to attend this objective, a total of 54 groundwater samples were collected and analyzed during January 2008 for the major cations (sodium, calcium, magnesium and potassium), anions (chloride, sulfate, bicarbonate), trace elements (boron, strontium and fluoride), and physicochemical parameters (temperature, pH, total dissolved salts and electrical conductivity). The evolution of chemical composition of groundwater from recharge areas to discharge areas is characterized by increasing sodium, chloride and sulfate contents as a result of leaching of evaporite rock. In this study, three distinct chemical trends in groundwater were identified. The major reactions responsible for the chemical evolution of groundwater in the investigated area fall into three categories: (1) calcite precipitation, (2) gypsum and halite dissolution, and (3) ion exchange. Based on the physicochemical analyses, irrigation quality parameters such as sodium absorption ratio (SAR), percentage of sodium, residual sodium carbonate, residual sodium bicarbonate, and permeability index (PI) were calculated. In addition, groundwater quality maps were elabortaed using the geographic information system to delineate spatial variation in physico-chemical characteristics of the groundwater samples. The integration of various dataset indicates that the groundwater of the Djeffara aquifers of the northern Gabes is generally very hard, brackish and high to very high saline and alkaline in nature. The water suitability for drinking and irrigation purposes was evaluated by comparing the values of different water quality parameters with World Health Organization (WHO) guideline values for drinking water. Piper trilinear diagram was constructed to identify groundwater groups where the relative major anionic and cationic concentrations are expressed in percentage of the milliequivalent per liter (meq/l), and it was demonstrated that the majority of the samples belongs to SO₄–Cl–Ca–Na, Cl–SO₄–Na–Ca and Na–Cl hydrochemical facies. As a whole, all the analyzed waters from this groundwater have revealed that this water is unsuitable for drinking purposes when comparing to the drinking water standards. Salinity, high electric conductivity, sodium adsorption ratio and sodium percentages indicate that most of the groundwater samples are inappropriate for irrigation. The SAR vary from medium (S2) to very high (S4) sodicity. Therefore, the water of the Djeffara aquifers of the northern Gabes is dominantly of the C4–S2 class representing 61.23 % of the total wells followed by C4–S3 and C4–S4 classes at 27.27 and 11.5 % of the wells, respectively. Based on the US Salinity Classification, most of the groundwater is unsuitable for irrigation due to its high salt content, unless certain measures for salinity control are undertaken.     

A geochemical assessment of coastal groundwater quality in the Varahi river basin, Udupi District, Karnataka State, India

The Varahi Irrigation project site is located at 13°39′15″N (latitude) and 74°57′E (longitude) in Hole Shankaranarayana village, approximately 6 km from Siddapura, Kundapura taluk, Udupi district. A total of 59 groundwater samples were collected from dug and tube wells in November 2008 to evaluate hydrochemistry and suitability for drinking and irrigation purposes. The physico-chemical parameters estimated include pH, electrical conductivity (EC), total dissolved solids (TDS), redox potential (Eh), total hardness (TH), total alkalinity (TA), temperature, major cations and anions, besides irrigation quality parameters like boron, sodium absorption ratio (SAR), % Na, residual sodium carbonate (RSC), residual sodium bicarbonate (RSBC), chlorinity index, soluble sodium percentage (SSP), exchangeable sodium ratio (ESR), non-carbonate hardness, potential salinity (PS), permeability index (PI), Kelly index (KI), magnesium hazard (MH), magnesium ratio (MR), index of base exchange. Chloride, sulphate and bicarbonate concentrations classified the groundwater samples into normal chloride, normal sulphate and normal bicarbonate water types, respectively. The Salinity (Class I; 98.3%), Chlorinity (Class I; 100%) and Sodicity (Class 0; 96.6%) indices suggest the suitability of groundwater for irrigation. The Wilcox diagram illustrates that 96.6% of the samples belongs to excellent to good category, while the US Salinity Laboratory (USSL) diagram indicates the low salinity/low sodium content in 86.44% of samples (C1S1). Positive index of base exchange in majority of the samples (91.52%) indicates direct base exchange reaction or chloro-alkaline equilibrium in the study area. The positive value of RSC in majority of samples signifying higher concentrations of HCO₃ over alkaline earths indicates that groundwater are base exchange-softened water as there is an exchange of alkaline earths for Na⁺ ions. Majority of water samples fall in the precipitation dominance field based on Gibbs’ ratio.     

Hydrochemistry of groundwater in a coastal region and its repercussion on quality,a case study—Thoothukudi district,Tamil Nadu,India

A hydrogeochemical study was conducted in Thoothukudi district situated in the southeast coast of Tamil Nadu, India to identify the influence of saltwater intrusion and suitability of groundwater for domestic and agricultural purposes. Scattered studies of this coastal region have reported signs of seawater intrusion, salt pan and industrial activity together with natural weathering process. To have a holistic picture of geochemical processes in the entire district, a total of 135 groundwater samples were collected and analyzed for major cations and anions. The geochemical parameters were compared with world and Indian standards and it was found that most samples are unsuitable for drinking purpose. The geochemical facies of the groundwater showed Na–Cl as the dominant water type indicating the saline nature of the groundwater. Chadda’s plots show that most of the samples fall in the Na–Cl type of water due to seawater intrusion. The samples were classified with parameters like sodium absorption ratio, residual sodium carbonate, total hardness, chloride, index to base exchange, electrical conductivity and facies to determine their suitability for irrigation purpose. It was inferred that the samples falling along the coast are not suitable for the irrigation purpose. The seawater-mixing percentage indicates that strong mixing was observed in the near shore and at the proximity of the salt pan. The permanent hardness was predominant in all the samples compared to the carbonate hardness reducing its domestic usability.     

Hydrochemical and bacteriological analyses of groundwater and its suitability for drinking and agricultural uses at Manfalut District,Assuit, Egypt

The present work focuses on the evaluation of the groundwater quality by chemical and bacteriological analyses to ensure its suitability for drinking and irrigation. Twenty groundwater samples were collected and analyzed from Manfalut district, Assiut, Egypt. Several water quality parameters were determined; the results show higher concentration of total dissolved solids (50 %), electrical conductivity (55 %), chloride (20 %), total hardness (20 %), and bicarbonate (55 %). This indicates signs of deterioration regarding drinking and domestic uses. Salinity hazard, sodium absorption ratio, sodium (Na) percentage, and residual Na carbonate were used to evaluate groundwater quality for irrigation. The values of electrical conductivity and SAR of groundwater samples were estimated illustrating that the most dominant classes are C2S1 (45 %; medium-salinity-low SAR), C3S1 (50 %; high-salinity-low SAR), and C4S1 (5 %; very high-salinity-low SAR). Bacteriological analysis was also conducted for 20 groundwater wells from December 2011 to May 2012. Seven samples (35 %) are contaminated by bacteria (total and fecal coliforms); these wells are not suitable for drinking. The analysis exhibits that bacterial contamination was the maximum in wells located at the center of the study area; this may be due to using the residential septic tanks. It was also discovered that the quality of groundwater is suitable for irrigation in the target aquifer except in a few locations. As for drinking, about 55 % of the samples are not suitable. However, the groundwater wells which are located in the center of the study area are suitable for drinking according to the hydochemical analysis. It was found that some of these wells are not suitable based on bacteriological analysis.     

Impact of recharge from a check dam on groundwater quality and assessment of suitability for drinking and irrigation purposes

Assessment of surface water and groundwater quality is necessary as it controls their usability for drinking and irrigation purposes. This study was carried out to assess the suitability of groundwater for these purposes and to understand the impact of water stored in a check dam on groundwater quality near Chennai, Tamil Nadu, India. Water samples were collected from a check dam across Arani River and 13 nearby wells during October 2010, January 2011, and April 2011. These samples were analyzed for pH, electrical conductivity (EC), and calcium, magnesium, sodium, potassium, carbonate, bicarbonate, chloride, and sulfate concentrations. The World Health Organization and the Bureau of Indian Standards guidelines were used to assess the suitability of groundwater for the purpose of drinking. Suitability of water for irrigation was determined based on the EC, sodium adsorption ratio, US Salinity Laboratory diagram, percentage sodium, Wilcox’s diagram, Kelly’s index, and Doneen’s permeability index. About 38 % of the groundwater samples were suitable for drinking and 70 % were suitable for irrigational use. Water stored in the check dam and groundwater in the wells closer to the structure were suitable for both drinking and irrigation purposes. The study confirms that the check dam in this area improves the groundwater quality in its surroundings.     

Evaluation of groundwater quality in the Cihanbeyli basin, Konya, Central Anatolia, Turkey

The Cihanbeyli basin is located in the northern part of Konya in the Central Anatolian region, Turkey and is characterized by semi-arid climatic conditions and scarcity in water resources. The suitability of groundwater quality for drinking and agricultural purposes in the Cihanbeyli basin was assessed by measuring physicochemical parameters, including major cation and anion compositions, pH, total dissolved solid, electrical conductivity, and total hardness. For this purpose, 54 samples were collected from different sources viz. deep wells, shallow wells, and springs. Results from hydrochemical analyses reveal that groundwater is mostly affected by salty and gypsiferous lithologies. Evaporite minerals such as gypsum, anhydrite, and chloride salts make high contributions from the recharge areas (west, northwest, and southwest parts) toward the discharge area (central and eastern parts). High values of total dissolved solids in groundwater are associated with high concentrations of all major ions. A comparison of groundwater quality in relation to drinking water standards showed that most of the water samples are not suitable for drinking. Based on sodium absorption ratio values and percent sodium, salinity appears to be responsible for the poor groundwater quality, rendering most of the samples unsuitable for irrigation usage. It is concluded that evaporation and mineral dissolution are the main processes that determine major ion compositions.     

Hydrochemical characterization and geospatial analysis of groundwater quality in Cap Bon region,northeastern Tunisia

The hydrogeochemical characteristics of shallow groundwater in the Grombalia region, northeastern Tunisia, were investigated to evaluate suitability for irrigation and other uses and to determine the main processes that control its chemical composition. A total of 21 groundwater samples were collected from existing wells in January–February 2015 and were analyzed for the major cations and anions concentrations. Conductivity, pH, T°, O₂ and salinity were also measured. Interrelationships between chemical parameters were determined by using the scatter matrix method. The suitability of groundwater for irrigation and other uses was assessed by determining the sodium adsorption ratio, soluble-sodium percentage, total dissolved solids, total hardness, Kelly’s index and permeability index values of water samples. The spatial distribution of key parameters was assessed using a GIS-based spatial gridding technique. This analysis indicated that the chemical composition of groundwater in the study area is of Cl–SO₄–Na–Ca mixed facies with concentrations of many chemical constituents exceeding known guideline values for irrigation. The salinity of groundwater is controlled by most dominant cation and anion (Na–Cl). A correlation analysis shows that Na⁺ is the dominant cation and that reverse ion exchange is a dominant process that controls the hydrogeochemical evolution of groundwater in the area. Geospatial mapping of hydrochemical parameters and indices analyzed with the USSL and Wilcox diagrams show distinctive areas of irrigation suitability. In contrast, 76.2% of samples fall in the highly doubtful to unsuitable category and indicate that the central and north-eastern parts of the study area are unsuitable for irrigation due to a high salinity and alkalinity.     

Spatial assessment of groundwater quality in the Jangseong region,South Korea

A total of 129 groundwater samples were collected in the Jangseong region of South Korea to characterize and evaluate groundwater quality and its suitability for irrigation and domestic uses. Samples were chemically analyzed for major ions, pH, electrical conductivity, and total dissolved solids following standard methods. The AquaChem 2014.2 model linked with PHREEQC was used for the statistical analysis and characterization of the hydrochemistry of the groundwater. The analysis showed that in all samples Ca–HCO₃ was the leading water type and that the abundance of major cations was in the order Ca > Na > Mg > K, and of anions in the order HCO₃ > Cl > SO₄ > F. According to the correlation analysis, Ca showed strong interdependence with HCO₃, suggesting that these parameters may have originated from common sources. Saturation index calculations indicated that all samples were undersaturated with respect to aragonite, calcite, dolomite, fluorite, gypsum, halite, and siderite, and oversaturated with respect to goethite and hematite. The irrigation suitability analysis revealed that groundwater in the Jangseong area can be used for irrigation without any restrictions based on EC, sodium adsorption ratio, percent sodium, residual sodium carbonate, Kelley ratio, permeability index, and the US Salinity Laboratory diagram analysis. The drinking water suitability analysis made for major parameters by comparison with the WHO guidelines indicates that the groundwater in the area is suitable for drinking except in some samples with high nitrate–N concentrations. The elevated nitrate concentrations in the groundwater are likely an indicator of agricultural pollution.     

Assessment of groundwater quality and its suitability for domestic and agricultural uses in Low-Isser plain,Boumedres, Algeria

The assessment of the suitability of groundwater for drinking and irrigation uses was carried out in the alluvial plain of Low-Isser in the north of Algeria. The plain covers an area of 533 km² and lies in a Mediterranean sub-humid climate. Groundwater is the main source for domestic uses and agricultural activities in this area. Groundwater samples were collected from 15 wells during dry and wet seasons in 2015, and they were analyzed for major cations and anions and compared with drinking and irrigation specification standards. The comparison of chemical concentration with WHO drinking water standards of 2006 shows that more than 30% of groundwater samples are unsuitable for drinking, and the majority of groundwater samples fell on the hard and very hard categories. Suitability of groundwater for drinking was also evaluated based on the water quality index (WQI). It shows more than 80% of samples have good or permissible water quality for dry and wet seasons. In terms of the irrigation usage, generally, groundwater in the study area is suitable for different uses in both seasons according to SAR, %Na, RSBC, and PI. However, water rock exchange processes and groundwater flow have been responsible for the dominated water type Ca–Mg–Cl.     

A study of groundwater irrigation water quality in south-central Bangladesh: a geo-statistical model approach using GIS and multivariate statistics

Southern Bangladesh’s irrigation and drinking water is threatened by saline intrusion. This study aimed to establish an irrigation water quality index (IWQI) using a geostatistical model and multivariate indices in Gopalganj district, south-central Bangladesh. Groundwater samples were taken randomly (different depths) in two seasons (wet-monsoon and dry-monsoon). Hydrochemical analysis revealed groundwater in this area was neutral to slightly alkaline and dominating cations were Na⁺, Mg²⁺, and Ca²⁺ along with major anions Cl^? and HCO₃ ^?. Principal component analysis and Gibbs plot helped explain possible geochemical processes in the aquifer. The irrigation water evaluation indices showed: electrical conductivity (EC) >750 µS/cm, moderate to extreme saline; sodium adsorption ratio (SAR), excellent to doubtful; total hardness (TH), moderate to very hard; residual sodium bicarbonate, safe to marginal; Kelly’s ratio >1; soluble sodium percentage (SSP), fair to poor; magnesium adsorption ratio, harmful for soil; and IWQI, moderate to suitable. In addition, the best fitted semivariogram for IWQI, EC, SAR, SSP, and TH confirmed that most parameters had strong spatial dependence and others had moderate to weak spatial dependence. This variation might be due to the different origin/sources of major contributing ions along with the influence of variable river flow and small anthropogenic contributions. Furthermore, the spatial distribution maps for IWQI, EC, SSP, and TH during both seasons confirmed the influence of salinity from the sea; low-flow in the major river system was the driving factor of overall groundwater quality in the study area. These findings may contribute to management of irrigation and/or drinking water in regions with similar groundwater problems.     

Hydrochemical characterization and suitability assessment of groundwater in Baga–Calangute stretch of Goa,India

The present study is the first attempt to determine the suitability of groundwater for drinking and irrigation in the Baga–Calangute stretch of Goa. The suitability of groundwater for potable use was assessed by comparing observed values against standards prescribed by the Bureau of Indian Standards, and the quality was classified based on the Weighted Arithmetic Water Quality Index. Most of the groundwater samples (90%) were found to be suitable for drinking except for hardness, chlorides, and nitrates. The percent sodium (%Na), residual sodium carbonate, soluble sodium percentage, sodium adsorption ratio, Kelly’s ratio, and Permeability Index were found to be within the prescribed limits for irrigation purposes. The major mechanism controlling groundwater chemistry, i.e., rock–water interaction, was also studied, and it was found that silicate weathering plays a major role in the dissolution of minerals. Based on the hydrochemical characterization, the water was observed to be of the Ca–Na–SO₄ composition type except for one sample which was of the Na–Cl composition type. Classification of the meteoric genesis suggested that the groundwater in surficial aquifers in the region had a deep meteoric percolation, and its chemistry is regulated by rock–water interaction.     

Assessment of groundwater quality for drinking and irrigation purposes: a case study of Peddavanka watershed, Anantapur District, Andhra Pradesh, India

In India, the quantity and quality of water available for irrigation is variable from place to place. Assessment of water quality has been carried out to determine the sources of dissolved ions in groundwater. Quality of groundwater in a 398 km² Peddavanka watershed of a semi-arid region of south India is evaluated for its suitability for drinking and irrigation purposes. The middle Proterozoic Cuddapah Supergroup and Kurnool Group of rocks underlie most of the watershed. The main lithologic units consist chiefly of quartzite, limestone, and shale. Seventy-six water samples were collected from open-wells and bore-holes. Water samples were collected representative of the post-monsoon (winter) and pre-monsoon (summer). The quality assessment is made through the estimation of Ca²⁺, Mg²⁺, Na⁺, K⁺, Cl⁻, SO₄²⁻, CO₃²⁻, HCO₃⁻, total hardness as CaCO₃, TDS, EC, and pH. Based on these analyses, parameters like sodium adsorption ratio, % sodium, residual sodium carbonate, non-carbonate hardness, potential salinity, Kelley’s ratio, magnesium ratio, index of base exchange and permeability index were calculated. According to Gibbs‘ ratio samples in both seasons fall in the rock dominance field. The overall quality of waters in the study area in post-monsoon season is high for all constituents ruling out pollution from extraneous sources.     

Hydrogeochemical investigation and groundwater quality assessment of Pratapgarh district,Uttar Pradesh

Hydogrochemical investigation of groundwater resources of Paragraph district has been carried out to assess the solute acquisition processes and water quality for domestic and irrigation uses. Fifty-five groundwater samples were collected and analyzed for pH, electrical conductivity, total dissolved solids, hardness, major anions (F^?, Cl^?, NO₃, HCO₃ ^?, SO₄ ^2?) and cations (Ca²⁺, Mg²⁺, Na⁺, K⁺). Study results reveal that groundwater of the area is alkaline in nature and HCO₃ ^?, Cl^?, Mg²⁺, Na⁺ and Ca²⁺ are the major contributing ions to the dissolved solids. The hydrogeochemical data suggest that weathering of rock forming minerals along with secondary contributions from agricultural and anthropogenic sources are mainly controlling the groundwater composition of Pratapgarh district. Alkaline earth metals (Ca²⁺+Mg²⁺) exceed alkalis (Na⁺+K⁺) and weak acid (HCO₃ ^?) dominate over strong acids (Cl^?+SO₄ ^2?) in majority of the groundwater samples. Ca-Mg-HCO₃ and Ca-Mg-Cl-HCO₃ are the dominant hydrogeochemical facies in the groundwater of the area. The computed saturation indices demonstrate oversaturated condition with respect to dolomite and calcite and undersaturated with gypsum and fluorite. A comparison of groundwater quality parameters in relation to specified limits for drinking water shows that concentrations of TDS, F^?, NO₃ ^? and total hardness exceed the desirable limits in many water samples. Quality assessment for irrigation uses reveal that the groundwater is good for irrigation. However, values of salinity, sodium adsorption ratio (SAR), residual sodium carbonate (RSC), %Na and Kelley index are exceeding the prescribed limit at some sites, demanding adequate drainage and water management plan for the area.     

Hydro-geochemical evaluation of groundwater with studies on water quality index and suitability for drinking in Sagardari,Jashore

Sagardari union is facing groundwater crisis because of contaminations from agriculture and urban sewage, which bring a considerable change in water quality. In view of this, hydro-chemical analyses were undertaken on 35 groundwater samples and the following hydro-geochemical parameters, pH, total dissolved solids (TDS), total hardness (TH), electrical conductivity (EC), cations and anions, were analyzed. From the analytical results, it is found that pH value was lower than WHO drinking water standard and the middle-downstream portions of the investigation region show higher EC. The piper plot indicates that the groundwater in Sagardari falls in the categories of NaClHCO₃ hydro-chemical facies. Higher TH in groundwater was detected, but still in an acceptable range. In addition, salinity and arsenic ratio are higher and moderately higher, respectively. The spatial distribution of Groundwater Quality Index (GWQI) was determined by geo-statistical modelling of Sagardari union. The study provides information and supports the administration which to make better groundwater utilization and quality control in the Sagardari union.     

Identification of hydrogeochemical processes and their influence on groundwater quality for drinking and agricultural usage in Wadi Nisah,Central Saudi Arabia

Groundwater quality of a region is often controlled by the geochemical processes that operate with respect to the aquifer-water interaction, especially in arid regions where rainfall recharge is minimal. The goal of the present research was to understand the hydrochemical processes influencing groundwater chemistry and to evaluate groundwater quality for drinking and agricultural usage in Wadi Nisah and Wadi Al-Awsat, south of Riyadh. Twenty-nine groundwater samples were analyzed for major physio-chemical parameters. Ionic plots, chloro-alkaline indices, and modified Piper plots point towards reverse ion exchange. Saturation indices and correlation coefficients indicate halite, calcite, and dolomite dissolution. The Piper plot shows that most of the groundwater samples (82.76%) are of the (Ca + Mg)–(Cl-SO₄) type. The groundwater quality is not good for drinking due to its high total dissolved solid (TDS) content. The groundwater is found to be suitable for irrigation in terms of residual sodium carbonate, sodium adsorption ratio, soluble sodium percentage, Kelly’s index, and magnesium hazard. The high salinity is unsuitable for irrigation; however, this can be overcome by using salinity-resistant crop varieties.