Introduction

One of the most valuable natural resource is Groundwater, which supports human health, socio-economic development and functioning of ecosystems (Humphreys 2009; Steube et al. 2009); besides, it forms one of the primary resources for development activities. Groundwater quality is one of the most important aspects in water resource studies. In recent times, there has been tremendous demand for fresh water due to population growth and intensive agricultural activities. The chemical parameters (Ca2+, Mg2+, Cl−, HCO3−, Na+, K+ and SO −24 ) of groundwater play a significant role in classifying and assessing water quality. Assessment of groundwater quality requires determination of ion concentrations which decide the suitability for drinking, domestic, agricultural and industrial uses. The water quality may yield information about the environments through which the water has circulated. Accordingly, groundwater quality is a function of its physical and chemical parameters which in turn are highly influenced by geological formations, climatic conditions and anthropogenic activities in any area (Ramkumar et al. 2012; Subramani et al. 2005a, b). Moreover, the use of pesticides and fertilizers enhances the agriculture production but they result in direct and negative impact on water quality (Carpenter et al. 1998; Matson et al. 1997; Kolpin 1997; Griffith 2001). According to Vasanthavigar et al. (2010), periodic changes in groundwater quality are caused by the constitution of the recharged water, hydrologic and human factors.

The Water pollution or water chemistry change not only affects water quality but also threatens human health, economic development and social prosperity (Milovanovic 2007). The quality of groundwater has particularly received immense attention since water of high quality is required for domestic and irrigation needs. The groundwater resources are not only the most important resources for drinking purposes but the groundwater exclusively fulfils agricultural, domestic and industrial water demands in India. Knowledge on hydrochemistry is important to assess the quality of groundwater for understanding its suitability for domestic, irrigation and industrial needs. Until recently, hydrochemical assessment of groundwater was based on laboratory investigation, but nowadays, geosciences research is carried out in different fields using geospatial techniques having advantage of observing and integrating various thematic layers with ease, accuracy and in time effective manner (Ali 2000; Ali and Piresteh 2004; Ali and Ali 1983, Ali and Ali 1984; Piresteh and Ali 2004; Ali et al. 2003a, b; Ali and Piresteh 2005; Pirasteh et al. 2007; Ali 1988; Ali and Khan 2013a, b; Ali and Tesgaya 2010; Ali and Ali 2014, 2015). The main objective of this study was to assess the spatial distribution of hydrochemical parameters, chemical variations in groundwater under various natural and anthropogenic activities. In this study, suitability of groundwater quality for various purposes like drinking, domestic, agriculture and industrial use in future was also analysed.

Description of study area

The present study is carried out in Lakheri river basin Jhansi district, Uttar Pradesh, India (Fig. 1). It covers an area of 390.03 km2 and is situated between 79°00′00″–79°15′00″E longitude and 25°15′00″–25°30′00″N latitude. The average annual rainfall is 850.1 mm. The climate is sub-humid and is characterized by a hot dry summer and cold winter. About 91% of rainfall takes place from June to September. In monsoon season, the availability of more surface water on percolation recharges and enhances the groundwater in the area. January is the coldest month of the year when the mean daily maximum temperature is 24.1 °C and the mean daily minimum temperature is 9.2 °C, May is the hottest month with mean daily maximum temperature is 42.6 °C and means daily minimum temperature is 28.8 °C. The mean monthly maximum temperature is 32.6 °C and means minimum temperature is 19.2 °C.

Fig. 1
figure 1

Location map of the area

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Geologically, the massif is mostly dominated by Palaeoproterozoic granitoids known as Bundelkhand Granitoids, which are described as pink granite, grey granite, biotite granite and granite porphyry (Singh et al. 2010). Singh et al. (2007), reviewed the geology of Bundelkhand and suggested that the Bundelkhand Gneissic Complex (BnGC) is the oldest component that comprises high-grade metamorphics reaching up to granulite facies (Singh and Dwivedi 2009) that is followed by low-grade metamorphic rocks of green schist facies of the Basement metamorphic complex, known as the Bundelkhand metasedimentaries and metavolcanics (BMM). These low- and high-grade metamorphites have angular relationships with each other and are characterized by polyphase deformation. Physiographically, the area has been divided into two units, i.e. Southern Bundelkhand Pediplane Province and Northern Highly Eroding Composite Plain Province.

  1. A.

    North block (Jhansi–Lalitpur) comprises vast area with inclusion of metasediments and has regional Precambrian granite.

  2. B.

    The South block (south of Lalitpur) consists of Bundelkhand granitoid flanked in south by medium and low-grade metasedimentary of Mehroni group and sedimentary sequence of Bijawars. The study area is part of block ‘B’ (Fig. 2).

    Fig. 2
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    Geology of the study area

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Materials and methods

For the present study, groundwater samples were collected at equally distributed locations to cover the entire study area. For collecting groundwater samples, plastic bottles were first washed by distilled water. The bottles containing groundwater samples were closed in field and were transported without any spillage. The chemical analysis of all the groundwater samples was carried out using standard methods recommended by American Public Health Association (APHA 1998). Some of the parameters of groundwater such as Temperature, ph and EC (Electrical Conductivity) were measured on spot in the field. Chemical analysis of all the samples for Na+, K+, Ca2+, Mg2+, F−, Cl−, NO3− and SO42− was carried out and were compared with standard values recommended by BIS. Moreover, the chemical parameters like PH, Hardness, TDS, Na+, K+, Ca2+, Cl− and SO42− were selected separately for generation of spatial distribution maps using point data analysis in GIS environment. Survey and India (SOI) Topo sheets, ERDAS Imagine 9.1, Arc GIS 10.2, Rockworks15 softwares were used for this spatial analysis and other diagrammatical representations of chemical data. For spatial analysis, point feature is prepared using the location data showing the position of water sample locations with the help of GPS technology to enhance spatial accuracy. The data obtained from chemical analysis for each groundwater sample are stored in excel format and is added to each point spatially drawn in Arc GIS 10.2 for the entire study area. These spatial and non-spatial data bases are jointly applied for generation of spatial distribution maps for analysing variation in hydrochemical parameters. The approach used to delineate the anomalous areas with respect to drinking, domestic and irrigation purpose from spatial distribution maps is Kriging and Inverse Distance weighted (IDW) spatial interpolation techniques.

Results and discussion

Physicochemical parameters of groundwater

The groundwater quality analysis is important in determining its suitability for different purposes. Physical and chemical parameters including statistical measures, such as minimum, maximum, mean and standard deviation are reported in (Tables 1, 2). The following water quality parameters were selected and their respective maps were prepared: pH, EC, TDS, TH, Cl−, SO42−, NO3−, Na+, Ca2+,Mg2+ and K; using point data spatial analysis of Arc GIS 10.2.

Table 1 Hydrochemical parameters
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Table 2 Hydro-chemical parameters
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Hydrogen ion concentration (pH)

The pH value indicates the acidic or alkaline material present in the water. When substance dissolve in water they produced charged molecules called ions. Hydrogen (H+) ions are found more in acidic water whereas Hydroxyl (OH−) ions are in basic water. The pH scale ranges from 0 to 14, with 7 being neutral for pure water. Acidic water has pH values less than 7, with 0 being the most acidic; likewise the basic water has value greater than 7, with 14 being the most basic. A change in pH from 7 to 6 indicates that there is a tenfold increase in hydrogen ion concentration. Similarly, a change in pH from 7 to 8 indicates a tenfold increase in the hydroxyl ion. In the area, the pH of water samples range from 8.14 to 9.14 (Fig. 3a) with an average of 8.615 which indicates that groundwater of this area is generally alkaline in nature. The pH value in some parts of the study area was found to be 9.0 which is beyond the permissible limit as per Bureau of Indian Standards, due to the seepage of effluent and domestic sewage. If pH is not within the permissible limit, it damages mucous membrane present in nose, mouth, eye, abdomen and anus in human beings.

Fig. 3
figure 3

Spatial distribution map of PH, Hardness, TDS and Calcium

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Total dissolved solids (TDS)

Water used for irrigation can vary greatly in quality depending upon type and quantity of dissolved salts. They originate from dissolution or weathering of the rocks and soil, including dissolution of lime, gypsum and other slowly dissolving soil minerals. These salts are carried with the water wherever it is used. In case of irrigation, the salts are mixed with the water and remain behind in the soil as water evaporates or is used by the crop. Salinity problem exists if salt accumulates in the crop root zone to a concentration that causes a loss in yield. Water with TDS up to 500 mg/l is considered desirable for drinking, 500–1000 mg/l is permissible for drinking, up to 3000 mg/l is useful for irrigation and the greater than 3000 mg/l is unsuitable for drinking and irrigation purposes (Davis and DeWiest 1966). The Total dissolved solids (TDS) observed for this area are between 1140 and 1960 mg/l and it reveals that water has moderate quality because TDS ranges around 1000–2000 mg/l (Fig. 3c). The TDS in the area may be due to influence of anthropogenic sources such as domestic sewage, industrial waste, septic tanks, agricultural activities and influence of rock–water interaction. Generally, the higher TDS causes gastro-intestinal irritation to the human beings and the prolonged intake of water with the higher TDS can also cause kidney stones and heart diseases (Garg et al. 2009).

Total hardness

Total hardness (TH) is caused primarily by the presence of cations such as calcium and magnesium and anions such as carbonate, bicarbonate, chloride and sulphate in water. Water hardness has no known adverse effects; however, some evidences indicate its role in heart diseases (Schroeder 1960) and hardness of 150–300 mg/l and above may cause kidney problems and kidney stone formation (Jain 1998), as it causes unpleasant taste and reduce ability of soap to produce lather. Total hardness is an important parameter of water for its use in domestic purpose. The acceptable limits for domestic use are 75 mg/l. Hard water is unsuitable for domestic use. In this area, the total hardness varies between 72 and 344 mg/l (Fig. 3b) with an average of 173.26 mg/l, which reveals that most of the samples are moderately hard to very hard water given in Table 3 (Sawyer and Mc Carty 1967). The ill effects of excess hardness are its undesirability mostly for economic or aesthetic reasons.

Table 3 Hardness classification of Water (After Sawyer and McCarty 1967)
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Magnesium (Mg2+) and Calcium (Ca2+)

Magnesium content of water is considered as one of the most important qualitative criteria in determining the quality of water for irrigation (Table 4). Calcium, magnesium and total hardness in the groundwater are inter-related. Generally, calcium and magnesium maintain a state of equilibrium in most waters. More magnesium in water will adversely affect crop yields as the soils become more alkaline. Calcium (Ca2+) is an important element to develop proper bone growth. It is found alkaline in nature. Calcium content is very common in groundwater, because they are abundantly available in most of the rocks and also due to its higher solubility. However, the range of its availability depends on the solubility of calcium carbonate and sulphate. In the present study, the magnesium content in water of Lakheri river averages 31.39 mg/l which reveals that water is suitable for irrigation purpose in terms of magnesium content. The calcium concentration in water samples collected from the study area ranged from 3.2064 to 46.4928 mg/l (Fig. 3d) and with an average value of 20.41971 mg/l. Thus, all the samples on the basis of calcium content fall in desirable limit for drinking purposes.

Table 4 Groundwater desirable and permissible limits prescribed by BIS for drinking purposes
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Magnesium (Mg2+) usually occurs in lesser concentration than calcium due to the fact that the dissolution of magnesium-rich minerals is slow process and that of calcium is more abundant in the earth’s crust. If the concentration of magnesium in drinking water is more than the permissible limit, it gives unpleasant taste to the water. Magnesium is an essential ion for functioning of cells in enzyme activation, but at higher concentrations it is considered as laxative agent (Garg et al. 2009), while deficiency may cause structural and functional changes in human beings. The acceptable limit is 30 mg/l as per standards (BIS 1991). In this area, the magnesium level in the water samples ranged from 1.949179 to 65.29751 mg/l with an average 31.39205. Therefore, the Mg2+ content exceeds the desirable limit in most of the water sample locations in the area.

Sodium (Na+)

Sodium concentration is important in classifying irrigation water because sodium reacts with soil to reduce its permeability. Excess sodium in waters produces undesirable effects by changing soil properties and reducing soil permeability. Hence, the assessment of sodium concentration is of utmost importance while considering the suitability of irrigation water. In all natural waters per cent of sodium content is a parameter to evaluate its suitability for agricultural purposes (Wilcox 1948); sodium combining with carbonate can lead to the formation of alkaline soils, while sodium combining with chloride forms saline soils. Both these soils do not help for the growth of plants. Sodium content is usually expressed in terms of per cent sodium (%Na) and Sodium (Na+) occurs as a major cation in the water samples obtained by the following equation:

$${\text{Na}}^{ + } \% = ({\text{Na}}^{ + } + {\text{K}}^{ + } ) \times {{100} \mathord{\left/ {\vphantom {{100} {\left( {{\text{Ca}}^{2 + } + {\text{Mg}}^{2 + } + {\text{Na}}^{ + } + {\text{K}}^{ + } } \right)}}} \right. \kern-0pt} {\left( {{\text{Ca}}^{2 + } + {\text{Mg}}^{2 + } + {\text{Na}}^{ + } + {\text{K}}^{ + } } \right)}},$$

where ionic concentrations are in epm. The calculated values of per cent sodium range 10.13–53.83 ml/l (Fig. 4a) with an average of 30.7.

Fig. 4
figure 4

Shows spatial distribution map of Sodium

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The chemical quality of groundwater samples was studied from plots of percentage of sodium and electrical conductivity on the Wilcox diagram. Wilcox diagram revealed that out of 19 samples in the study area 82 per cent belongs to permissible to doubtful category, followed by 18 per cent samples belonging to good to permissible category for irrigation (Table 5). The agricultural crop yields are generally low in lands irrigated with waters belonging to permissible to doubtful category. This is probably due to the presence of excess sodium salts, which causes osmotic effects on soil plant system. When the concentration of sodium is high in irrigation water, sodium ions tend to be adsorbed by clay particles, displacing Mg and Ca ions. This exchange process of Na in water for Ca and Mg in soil reduces the permeability and eventually results in soil with poor internal drainage. Hence, air and water circulation is restricted during wet conditions and such soils are usually hard when dry (Collins and Jenkins 1996; Saleh et al. 1999). Also the sodium concentration more than 50 mg/l makes the water unsuitable for domestic use because it causes severe health problems like hypertension (Patnaik et al. 2002). The higher concentration of sodium may pose a risk to persons suffering from cardiac, renal and circulatory diseases (Haritash et al. 2008).

Table 5 Sodium percentage water class (After Sadashivaiah et al. 2008)
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Potassium (K+)

Generally the behaviour of potassium (K+) is similar to the sodium content in the water but not found in the concentration as much as the sodium in groundwater. It maintains fluids in balance stage in the human body. In present investigation, potassium concentration ranged from 4 to 80 mg/l (Fig. 4b) with an average value of 23.526. The permissible limit of potassium is 10 mg/l (BIS 1991) and in study area, 12 water sampling sites exceed the permissible limit. Thus, the excess amount of potassium present in the water sample may lead to nervous and digestive disorder (Tiwari and Mishra 1985). The higher values in the area may be contributed due to the effluent discharged by industries and domestic sewages. However, excessive fertilizer usage may also increase its concentration in groundwater.

Chloride (Cl−)

Chloride (Cl−) is a widely distributed element in all types of rocks in one or the other form. Therefore, its concentration is high in groundwater where the temperature is high and rainfall is less. Mostly, the chlorides are found in the form of sodium chloride in the groundwater. Soil porosity and permeability also has a key role in building up the chloride concentration. Chloride imparts a salty taste and some times higher consumption causes hypertension, risk for stroke, left ventricular hypertension, osteoporosis, renal stones and asthma in human beings (McCarthy 2004). Although the chloride plays an important role in balancing level of electrolyte in blood plasma, higher concentration can produce some physical disorders. In the area, the chloride concentration showed variation from 8.52 to 193.12 mg/l (Fig. 5a) with an average of 59.64. The limit of Cl− (mg/l) concentration is 250–1000 (BIS standard), 200 is maximum acceptable limit and 600 is maximum allowable limit for drinking water specification (WHO 1984).

Fig. 5
figure 5

Spatial distribution map of chloride and sulphate

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Spatial distribution shows few places with higher concentration, which could be dangerous from health point of view. The high chloride may be attributed to industrial, domestic wastes, leaching from upper soil layers in dry climates and natural geochemical activities in the area.

Sulphate (SO4 2−)

The sulphate (SO42−) ion one of the important anions present in natural water that produce catharsis, dehydration and gastrointestinal irritation effect upon human beings when it is present in excess of 150 mg/l. It is mainly derived from gypsum on oxidation of pyrites. The sulphide minerals add the soluble sulphate into the groundwater through oxidation process. In the present investigation, the sulphate concentration ranged from 82.3 to 411.5 mg/l with an average of 190.59 shown in spatial distribution diagram (Fig. 5b). In the area, seven places are having sulphate ion concentration more than 200 and the higher sulphate content may be contributed due to biochemical, anthropogenic sources and industrial process, etc.

Residual sodium carbonate (RSC)

Residual sodium carbonate (RSC) can be used as a criterion for assessing the suitability of irrigation waters. The water having higher carbonate and bicarbonate concentration than the alkaline earth mainly calcium and magnesium concentration, diminishes the water quality and affects agriculture unfavourably (Eaton 1950; Richards 1954). RSC can be computed using the following formula, where ions were expressed in meq/l:

$${\text{RSC}} = \left( {{\text{CO}}_{3}^{2 - } + {\text{HCO}}_{3}^{ - } } \right) - \left( {{\text{Ca}}^{2 + } + {\text{Mg}}^{2 + } } \right).$$

If RSC < 1.25 meq/l, the water is considered safe. If RSC lies between 1.25 and 2.5 meq/l, the water is of marginal quality. If RSC > 2.5 meq/l, the water is unsuitable for irrigation. The RSC variation was drawn using (Richards 1954) as good, medium and bad categories.

The classification of groundwater for irrigation purpose according to the RSC values indicates that about eighty per cent of the water samples are of unsuitable category, ten per cent samples are marginal and safe irrigation purposes. Continued usage of high residual sodium carbonate water affects the yields of crops.

The concentration of bicarbonate and carbonate also influences the suitability of water for irrigation purpose. One of the empirical approaches is based on the assumption that all Ca2+ and Mg2+ precipitate as carbonate. Considering this hypothesis, (Eaton 1950), proposed the concept of residual sodium carbonate (RSC) for the assessment of high carbonate waters. The water with high RSC has high pH and land irrigated with such water becomes infertile owing to deposition of sodium carbonate; as known from black colour of the soil. According to U.S. Salinity Laboratory, an RSC value less than 1.25 meq/l is safe for irrigation. A value between 1.25 and 2.5 meq/l is of marginal quality and value more than 2.5 meq/l is unsuitable for irrigation. In the present study, RSC values range between 0.26 and 15.64 meq/l with an average value 4.99. Only the location 9 (Rippa Dhamna) is considered excellent for irrigation in Table 6. Thus, water of Lakheri river cannot be considered safe for irrigation purpose as mentioned according to above considerations. Besides, bicarbonate is a major element in human body, which is necessary for digestion. The bicarbonate has no known adverse effects on human health; if it exceeds 300 mg/l in the drinking water, it may lead to kidney stones in the presence of higher concentration of Ca, especially in dry climatic conditions.

Table 6 Classification of samples on RSC value (Richards 1954)
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Permeability index (PI)

The soil permeability is affected by long-term use of irrigation water and is influenced by sodium, calcium, magnesium and bicarbonate contents of the soil. The permeability index (PI), as developed by (Doneen 1964), indicates the suitability of groundwater for irrigation. It is defined as follows:

PI = [(Na+ + √HCO3−)/(Ca2+ + Mg2+ + Na+)] 100 (All value are expressed in epm)

Sodium, calcium, magnesium and bicarbonate content of the soil influence it. Doneen (1964), evolved a criterion for assessing the suitability of water for irrigation based on the permeability index. In the present study, the minimum value of PI is 6.06 and maximum is 32.04 and the average value is 13.42.

Salinity

The EC and Na concentrations are important in classifying irrigation water. The electrical conductivity values range from 780 to 1540 μS/cm with an average of 1189 μS/cm given in Table 7. A high salt content (high EC) in irrigation water leads to formation of saline soil. This affects the salt intake capacity of the plants through their roots. On the basis of electrical conductivity values, Richards (1954) classified irrigation water into four groups. As per Richards classification, all 19 samples are fair. Groundwater samples falling in medium salinity hazard can be used, if a moderate amount of leaching occurs. High salinity waters cannot be used on soil with restricted drainage. Excess salinity reduces the osmotic activity of plants and thus interferes with the absorption of water and nutrients from the soil (Saleh et al. 1999).

Table 7 Salinity Classification (Richards 1954)
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Hydro-chemical facies

As water flows through an aquifer, it assumes a characteristic chemical composition as a result of interaction with the lithologic framework. The term hydro-chemical facies is used to describe the bodies of groundwater in an aquifer that differs in their chemical composition. The facies are a function of the lithology, solution kinetics and flow patterns of the aquifer. Hydro-chemical facies can be classified on the basis of dominant ions using the Piper’s trilinear diagram. The concentrations of major ionic constituents of groundwater samples were plotted in the Piper Trilinear diagram (Piper 1944) to determine the water type (Fig. 6). The classification for cation and anion facies, in terms of major-ion percentages and water types, is according to the domain in which they occur on the diagram segments. From the cationic and anionic triangular fields of Piper diagram, it is observed that 100% of groundwater samples fall into the no dominant type; conversely, 35% of these groundwater samples fall into the bicarbonate type and other 20% into the no dominant type and 45% into the sulphate type in anion facies. The diamond shaped field between the two triangles is used to represent the composition of water with respect to both cations and anions. The points for both the cations and anions are plotted on the appropriate triangle diagrams. The positions of the points are projected parallel to the magnesium and sulphate axes, respectively, until they intersect in the centre field. The plot of chemical data on diamond shaped trilinear diagram reveals that majority of groundwater samples fall in the fields of 1 and indicates that alkaline earth exceeds alkalies and alkalies exceeds alkaline earth. From the data plots (Fig. 6), it is apparent that the total hydrochemistry is dominated by alkaline earths.

Fig. 6
figure 6

Piper diagram for describing the hydro-chemical facies variation

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The ion concentration of sample of all locations is also shown by Durov Diagram (1948), which is alternative to the Piper diagram. In the Durov diagram, two triangles are used for ploting major ions as percentage of milliequavalent. The square grid which lies perpendicular to the third axis in each triangle, is used to project the data points from two triangles. According to the Durov diagram (Fig. 7), it can be found that sodium ion is high in each sample while as Cl and CO3 are two equally dominant ions in the water samples of the study area.

Fig. 7
figure 7

Durov diagram of water samples

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Groundwater for irrigation purpose

The water quality used for irrigation is essential for the crop yield and quantity, maintenance of soil productivity and protection of the environment. The quality of irrigation water is very much influenced by the land constituents of the water source. The important parameters affecting the suitability of groundwater for irrigation purposes are: Electrical Conductivity (EC), Sodium adsorption ratio (SAR), Sodium percentage (Na %) and Residual sodium carbonate (RSC).

The most influential water quality guideline on crop productivity is the water salinity hazard as measured by electrical conductivity (Ec). The primary effect of high Ec water on crop productivity is the inability of the plant to compete with ions in the soil solution for water (physiological drought). The higher the Ec, the less water is available to plants, even though the soil may appear wet. Because plants can only transpire “pure” water, usable plant water in the soil solution decreases dramatically as Ec increases. Water with Ec less than 250 μs/cm is considered good and that with greater than 750 μs/cm is unsuitable for irrigation in Table 8. The minimum Ec was recorded 780 μs/cm in the Mauranipur area. The maximum Ec was recorded 1540 μs/cm in the Markua area. The large variation in EC is mainly due to lithologic composition and anthropogenic activities prevailing in this region. It is observed that in some samples the EC values increase with the increasing amounts of sulphate, chloride, bicarbonate and hardness as CaCO3.

Table 8 Classification on the basis of EC (After Sarma and Narayanaswamy 1981)
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Sodium adsorption ratio (SAR)

Although sodium contributes directly to the total salinity, the main problem with a high sodium concentration is its effect on the physical properties of soil. The water with high salt (EC) leads to formation of saline soil while as high sodium (SAR) leads to development of an alkaline soil. This Na enriched water causes soil aggregates to disperse, reducing its permeability (Tijani 1994). The sodium hazard is typically expressed as sodium adsorption ratio (SAR). This index quantifies the proportion of sodium to calcium and magnesium ions in a water sample. Sodium hazard of irrigation water can be well understood by knowing SAR. Sodium Adsorption Ratio (SAR) is most commonly used to assess suitability of irrigation water. The SAR measures sodicity in terms of the relative concentration of sodium ions to the sum of calcium and magnesium ions in a water sample. Sodium concentration in water effects deterioration of the soil properties reducing permeability (Richards 1954). SAR is calculated using the following formula:

SAR = Na+/√[(Ca2+ + Mg2+)/2], where the ionic concentrations are expressed in meq/l.

Excess sodium in waters produces the undesirable effects of changing soil properties and reducing soil permeability. Hence, the assessment of sodium concentration is necessary while considering the suitability for irrigation. The degree to which irrigation water tends to enter into cation-exchange reactions in soil can be indicated by the sodium adsorption ratio. Sodium replacing adsorbed calcium and magnesium is a hazard, as it causes damage to the soil structure. It becomes compact and impervious. SAR is an important parameter for the determination of suitability of irrigation water because it is responsible for the sodium hazard. The waters were classified in relation to irrigation based on the range of SAR values. Water with SAR ranging from 0 to 3 is considered good and with greater than 9 is considered unsuitable for irrigation purpose. In the present study, SAR was found in the range of 1.69–26.10 with an average value of 8.97. The high value of SAR for Lakheri river water cannot be categorized as water of excellent category. It cannot be used for irrigation on almost all soil types. The plot for SAR vs EC (Fig. 8) values when lesser than 10 indicates low SAR with medium salinity, high salinity, very high salinity and values greater than 10 requires careful management by application of gypsum, which makes water feasible and increases soil permeability (Goel 2000). Na is important cation which in excess deteriorates the soil structure and reduces crop yield (Srinivasamoorthy et al. 2009). When the concentration of Na is high in irrigation water, Na tends to be adsorbed by clay particles displacing Mg and Ca ions. This exchange process of Na in water for Ca and Mg in soil reduces the permeability and results in soil with poor internal drainage. Hence, air and water circulation is restricted during wet conditions and become hard when dry (Collins and Jenkins 1996). Na causes an increase in the hardness of soil as well as reduction in its permeability (Tijani 1994).

Fig. 8
figure 8

US salinity diagram for classification of irrigation waters (after Richards 1954)

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There is a significant relationship between sodium adsorption ratio of irrigation water and the extent to which sodium is absorbed by the soils. If water used for irrigation is high in sodium and low in calcium content, then exchangeable calcium in soil may replace sodium by Base Exchange reaction in water. This can destroy the soil structure owing to dispersion of the clay particles. The analytical data plotted on the U. S. Salinity Laboratory Diagram (Richards 1954) illustrates that most of the groundwater samples fall in the field of C3S1 (High salinity with low sodium), C3S2 (high salinity with medium sodium), C3S3 (high salinity with high sodium) and one sample fall in (high salinity with very high sodium) waters, which cannot be used for irrigation on almost all types of soil with little danger of exchangeable sodium.

The Stiff diagram (Fig. 9) is also used for investigation of cation and anion dominance at different locations. Sample wise composition is also shown by Stiff diagram which is in common cations and anions, with concentration represented in electrical equivalents. Analysis of Stiff diagram shows highest concentration of (Na + K) followed by Mg among the cations, whereas, in the area, anions (Cl, SO4, CO3) showed unequal dominance at different locations but Cl and CO3 concentration is more at some locations in the study area. The highest concentration of Na and CO3 may possibly increase pH, electrolyte conductivity (EC) and SAR of the soil.

Fig. 9
figure 9

Stiff diagram showing cation and anion concentration in all samples separately

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According to (Wilcox 1955) diagram Fig. 10, relating sodium percentage and total concentration, indicates that most of samples of the groundwater fall in the field of good to permissible suitability and five samples are unsuitable for irrigation, respectively. The agricultural yields are, generally, very low in the lands irrigated with the water of unsuitable category due to the presence of excess sodium salts. This causes osmotic effects on soil–plant system. In addition to the SAR and Na%, the excess sum of carbonate and bicarbonate in groundwater over the sum of calcium and magnesium also influences the unsuitability of groundwater for irrigation. This is termed as residual sodium carbonate (RSC) (Richards 1954). The RSC is calculated using the formula given below: RSC = (HCO3− + CO32−) − (Ca2+ + Mg2+), where the concentrations are expressed in meq/l. If RSC < 1.25 meq/l, the water is considered safe and is only for Rippa dhamna area. If RSC lies between 1.25 and 2.5 meq/l, the water is of marginal quality and is for Markua, Gursarai, Kotra and Dogra. If RSC > 2.5 meq/l, the water is unsuitable for irrigation. In the study area, most of the samples fall in RSC > 2.5 meq/l category which indicates water is not suitable for irrigation. The RSC variation was drawn using (Richards 1954) as good, medium and bad categories.

Fig. 10
figure 10

The Wilcox diagram of water samples

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Conclusion

Groundwater quality of an area was analysed to understand its suitability for drinking, domestic and irrigation purposes. The average pH of groundwater is 8.615 which indicates alkaline nature and an average hardness of 173.26 mg/l which reveals that most of the samples are moderately hard to very hard water. The TDS observed ranges between 1140 and 1960 mg/l indicate that water is of moderate quality. From the cationic and anionic triangular fields of Piper diagram, it is observed that 100% of groundwater samples fall into the no dominant type; conversely, 35% of these groundwater samples fall into the bicarbonate type, and other 20% into the no dominant type and 45% into the sulphate type in anion facies. The concentration of physiochemical constituents in the water samples was compared with the Bureau of Indian Standards (BIS) to know the suitability of water for drinking. Based on the analysis, most of the area at many locations in industrial area falls in moderately polluted to severely polluted, making the water unsuitable for drinking purposes. Various determinations such as sodium adsorption ratio (SAR), per cent sodium (Na%) and residual sodium carbonate (RSC) revealed that most of the samples are also unsuitable for irrigation. According to the quality classification of irrigation water proposed by Wilcox and US salinity classification, most samples fall in the permissible to doubtful range for irrigation purpose. It was observed that the quality of groundwater was not suitable for drinking purpose in industrial area. Ground water at some sampling sites is unsuitable because of influence of urban and industrial waste discharge, aquifer mineralogy and with other anthropogenic activities and increased intervention of humans in deteriorating the groundwater quality of the area. All these hydro -geochemical characteristics were spatially analysed so that it will be easily understood and beneficial to human society.