Evaluation of groundwater quality in the Chotanagpur plateau region of the Subarnarekha river basin, Jharkhand State, India

Health risk assessment of groundwater use for drinking in West Nile Delta, Egypt

Human health is at risk from drinking water contamination, which causes a number of health problems in many parts of the world. The geochemistry of groundwater, its quality, the origins of groundwater pollution, and the associated health risks have all been the subject of substantial research in recent decades. In this study, groundwater in the west Rosetta Nile branch of the Nile Delta Aquifer is examined for drinking potential. Numerous water quality indices were applied, such as water quality index (WQI), synthetic pollution index (SPI) models, and health risk assessment (HRA) method. The limits of the measured parameters are used to test its drinking validity on the basis of WHO recommendations. TDS in the southern regions is within the desirable to allowable limits with percent 25.3% and 29.33%, respectively. Nearly all the study area has desirable value for HCO3, Al and Ba. Ca and Mg have desirable values in the center and south portion of the investigated area, whereas in the north are unsuitable. Na, Cl and SO4 fall within the desired level in the regions of the south but become unsuitable towards the north. Mn and NO3 are inappropriate except in the northwestern part. Fe is within suitable range in the southwestern and northwestern regions. Pb, Zn, Cu, and Cd were undetected in the collected samples. Regarding to WQI the study area is classified into 4 classes good, poor, very poor and unfit for drinking water from south to north. According to SPI model, 20%, 18.7%, 18.7%, 8% and 34.6% of water samples are suitable, slightly, moderately, highly polluted and unfit, respectively from south to north. Based on HRA, Children are the most category endangered with percent 14.7% of the overall samples obtained, followed by females and males with percent 12% and 8%, respectively. This study offers insights into the conservation and management of coastal aquifers' groundwater supplies. These findings have significant implications for developing strategies and executing preventative actions to reduce water resource vulnerability and related health hazards in West Nile Delta, Egypt.

Assessment of groundwater quality and soil properties in recharge and discharge areas of a basement environment

This study examined the interaction between soil and groundwater in a recharge and discharge areas of Akungba-Akoko, Southwestern Nigeria. Ten water samples (R1-R5 from the recharge and D6-D10 from the discharge areas) and ten soil samples from trial pits were collected and analyzed for hydrochemical parameters (Ca2+, Mg2+, K+, Na+, Cl+, SO42+, NO3-, PO43-, Fe, Zn, and Pb) and geotechnical investigation. Ten Schlumberger vertical electrical sounding (VES) were carried out to determine the subsurface resistivity distribution. The concentrations of all the hydrochemical parameters including Ca2+ (0.06-0115 mg/L), Mg2+ (0.05-0.099 mg/L), K+ (0.021-0.042 mg/L), Cl- (3.778-9.885 mg/L), Zn (0.01-0.025 mg/L), and Pb (0.003-0.004 mg/L) were within the WHO stipulated standards. Geotechnical tests revealed that the soil was sandy-clay loam with a subgrade rating of A-2-6 or A-2-7 and medium compressibility, indicating the soil was suitable for agricultural purposes. Grain size analysis showed that the sand content of the soil (average = 48.2%) is ideal for agriculture. The VES model revealed four lithologic layers with four curve types (HA, AA, AK, and HK). The wells were located in clayey to sandy-rich weathered layer (66.9-794.4 Ωm) with an average thickness of 11.4 m. The thin layer was responsible for the observed variations in groundwater during the dry season. Two viable fracture zones were identified with good potential. The health risk assessment, drinking water, and irrigation indices (WQI, SAR, SSP, KR, and MH) indicated that the groundwater in both areas was good for drinking and irrigation purposes, with no associated health risks. Nine pairwise parameters were identified with a strong correlation between changes in groundwater quality (sodium content) and the resistivity response of the soil. Continued monitoring of groundwater quality and soil resistivity response will provide effective groundwater management strategies.

Assessment of seasonal water quality and land use land cover change in Subarnarekha watershed of Ranchi stretch in Jharkhand

In this paper, the assessment of seasonal water quality and land use land cover change in the Subarnarekha watershed in Ranchi stretch was analysed. Agricultural runoff along with climate change adds to the pollution risk to the Subarnarekha River of Ranchi stretch in Jharkhand. Water quality indicators, like acidity alkalinity (ALK), total dissolved solids (TDS), hardness (H), dissolved oxygen (DO), biochemical oxygen demand (BOD), chlorides (CL-), electrical conductivity (EC), salinity (SAL), resistivity (RES) and pH, were assessed as per the standard method. During monsoon season, acidity, alkalinity, hardness, chlorides, salinity, pH and DO decreased, whereas EC, TDS, BOD and resistivity increased in comparison to pre-monsoon season. In post-monsoon, chloride problem was observed very high. Hardness was least in monsoon and maximum in post-monsoon season. EC and BOD increased in monsoon season in comparison to other seasons. Statistical analysis like HCA (hierarchical cluster analysis) and PCA (principal component analysis) also confirmed the problem of TDS, EC, chloride and hardness in the area. WQI (water quality index) analysis showed that the water quality was poor to unsuitable on all the sampling points throughout the study area in all seasons. LULC (land use land cover) and NDWI (normalized difference water index) analysis had also concluded that due to high rate of urbanization, the area has undergone a massive change in terms of forest cover and water bodies. The need for afforestation, forest protection and wetland protection can be clearly seen from the result of this study.

An investigation into the influence of climate extreme on groundwater regimes and human health in the Periyar Basin: A fast growing urban centre in India

A total of 212 groundwater samples were collected during North East Monsoon (NEM), South West Monsoon (SWM), Pre-Monsoon (PREM), and Post-Monsoon (POM) seasons of 2020-2021 from the Periyar River Basin, draining the south western flanks of Western Ghats. The analytical results revealed the order of abundance of cations as Ca2+ > Na+ > Mg2+ > K+ and anions in the order of HCO3- > Cl- > SO42- > NO3- for all seasons. The major hydrochemical facies identified were CaHCO3 and mixed Ca-Mg-Cl in all the seasons with rock-water interaction as the key process regulating water chemistry. Ionic ratios of Ca2+ + Mg2+/Na+ + K+ and Ca2+/Mg2+ suggested significant effect of silicate minerals and other sources. The Water Quality Index (WQI) shows that the majority of the samples, namely, 98% in NEM, 86% in POM, 82% in PREM, and 95% in MON, fall in the categories ranging from excellent to good for drinking purposes. Furthermore, the health risk assessment based on carcinogenic and non-carcinogenic risk of the United States Environmental Protection Agency (US EPA) during monsoon and non-monsoon seasons for adults and children revealed the potential risk posed by Pb via oral exposure in the study area suggesting children being more susceptible to the damaging effects than adults.

Assessing drinking water quality in Eloued, south-East Algeria, using the groundwater pollution index (GPI) and the synthetic pollution index (SPI) model

Groundwater quality degradation is a significant environmental issue worldwide, with potentially severe economic consequences and harm to ecosystems and biodiversity. This can directly affect human health, particularly in developing countries where rapid and uncontrolled urbanization is on the rise. Groundwater is the primary resource for meeting the water needs of the Eloued region, located in southeastern Algeria. Water is considered unfit for human consumption if its physico-chemical elements exceed national or international standards or guidelines. We used the GPI and SPI indices to evaluate the quality of groundwater suited for drinking. Groundwater samples were obtained from 22 wells at depths of more than 250 m. Standard analytical procedures were used to determine the physicochemical characteristics of the collected samples, which included pH, EC, TDS, Na+, Ca+2, Mg+2, K+, Cl-, HCO3-, SO4-2, NO3-, NO2-, NH4+ and PO4-3. Multivariate statistical analysis and GIS techniques were used to process the results. The results of the selected physicochemical parameters were compared with World Health Organization (WHO) guidelines to determine the quality of drinking water. The findings indicate that the waters of the terminal complex aquifer are salty and contain medium to high quantities of main ions that surpass the established drinking water limits. The primary ions' relative abundance is Cl- > SO4-2 > HCO3- > NO3 for anions and Na+ > Ca+2 > Mg+2 > K+ for cations. Groundwater chemical types were dominated by Na+, Ca+2, Cl-, and SO4-2. Principal Component Analysis (PCA) showed that alteration and dissolution of carbonates, evaporates, salts, partly silicates, and evaporation, are the main reasons affecting the chemical composition of water in Eloued. The GPI results show that 18.18%, 54.54%, and 27.27% of the water samples were classed as lightly polluted, moderately polluted, or substantially polluted for drinking purposes, respectively. According to the SPI study, 9.09%, 36.36%, 36.36%, and 18.18% were considered drinkable, mildly contaminated, moderately polluted, and seriously polluted for drinking purposes, respectively. According to the GPI and SPI models' geographical distribution maps, potable water is generally scarce and concentrated in the northeastern section of the research area, near the town of Ourmes.

A correlational study of uranium in groundwater with other physicochemical parameters using GIS mapping in Godda district of Jharkhand, India

The present research concentrates on the cumulative use of GPS and GIS technologies, which are excellent resources for analyzing and monitoring divergent physicochemical parameters in groundwater, including pH, TDS, EC, ORP, Ca+2, Mg+2, NO3-, F-, SO4-2, Cl- and PO4-3 with explicit regard to uranium. Garmin GPS is used to record the locations of the sampling points in the Godda study area. The research aims to offer a thorough understanding of the relationship between soil and water, its impact on public health and the extent to which water can be used in various ways based on its quality. Utilizing the inverse distance weighted (IDW) technique, it is examined how these groundwater parameters and the Water Quality Index (WQI) can be estimated spatially. Additionally, a correlation analysis of the water quality parameters is computed to estimate the local population's cancer risk living in the study area. Except for calcium and magnesium, which are present in excess concentrations throughout the study area with the highest values of 325 and 406 mg/l, respectively at Amediha and Meherma, the results showed that the maximum concentration parameters are within limits with the standard. The main reason might be the area's predominance of Alfisol soil type. The radioactive element uranium is found to be in a limited  range. Chemo-toxicity and radiological risk assessment of the whole area lie far below the restricted cancer risk limit i.e., 30 ppb with the highest concentration of 14 ppb in the 'Sunderpahari' region, following the results obtained. The WQI for the area ranges from 'good' to 'very poor.' The results were favorable but a few sites such as 'Boarijor' and its surroundings, require additional attention to enhance groundwater quality. Given uranium's low availability in groundwater the region's cancer risk assessment is below average.

Spatiotemporal evaluation and assessment of shallow groundwater quality for irrigation of a tropical coastal groundwater basin

The present study aims at analyzing groundwater quantity and quality simultaneously to identify its availability and suitability for irrigation. Various water quality indices were used to assess (i) origin of the groundwater sources (Gibbs diagram); (ii) salinity, alkalinity, and sodium hazard (sodium adsorption ratio, exchangeable sodium percentage, Kelly's ratio, US Salinity Laboratory diagram, Wilcox diagram); (iii) magnesium hazard (magnesium absorption ratio); (iv) carbonate and bicarbonate hazard (residual sodium carbonate); (v) hydro-chemical facie and evaluation (Piper diagram and Expanded Durov diagram); and (vi) statistical relationship among the variables, sample sites, and spatiotemporal grouping (principal component analysis and cluster analysis). The overall objective is to quantify the irrigation suitability of groundwater reserves. Gibb's diagram suggests that the groundwater quality is mainly controlled by rock-water interaction. Piper trilinear showed the presence of various types of hydro-chemical facies such as Ca-Mg-HCO3, mixed, and sodium bicarbonate. The expanded Durov diagram revealed the hydro-chemical evolution, grouping, and areal distribution of the groundwater samples. USSL diagram, Wilcox diagram, Kelly's ratio, magnesium hazard, and permeability index suggest that the groundwater quality is suitable for irrigation. Kaiser-Meyer-Olkin (KMO) and Bartlett's tests confirmed the applicability of principal component analysis (PCA), which indicates that groundwater quality is controlled by rock-water interaction mainly. It also suggests that the groundwater has carbonate dissolution, which indicates the groundwater's hardness increased. Cluster analysis (CA) from the year 2000 to 2010 shows 4 to 8 groups present within the study area. Irrigation water quality suitability map and predicted groundwater potential zone map together act as a master tool for deciding tube well location, pumping schedule, and crop planning for the sustainability of the agriculture eco-system in the study area. The implementation of the aforementioned activities in the study area will further stop the advancement of the seawater intrusion front. The methodology shows the potential applicability for similar coastal groundwater basins worldwide with or without modification.

Deployment of entropy information theory in the Indian Sundarban region using hydrogeochemical parameters and GIS for assessment of irrigation suitability

The evaluation of irrigation suitability plays a crucial role for the socio-economic development of the society, especially in the region of Sundarban. For sustainable agricultural practices, groundwater quality must be suitable for irrigation; otherwise, it can degrade soil and diminish crop yield. The entropy information theory, several irrigational indices, multivariate statistics, GIS, and geostatistics are used in this work to evaluate the geographical distribution and quality of groundwater in the Indian Sundarban region. In total, 33 groundwater samples were collected in 2018 (April and May), and they were evaluated for major cations, anions, as well as other parameters like electrical conductivity (EC), soluble sodium percentage (SSP), potential salinity (PS), total dissolved solids (TDS), Kelly ratio (KR), sodium absorption ratio (SAR), permeability index (PI), residual sodium carbonate (RSC), magnesium hazard (MH), and residual sodium bicarbonate (RSBC). The overall trend of the principal cations and anions is in the sequence of Na+  ≥ Mg2+  ≥ Ca2+  ≥ K2+ and HCO3-  ≥ Cl-  ≥ NO3-  ≥ SO42-  ≥ F-, respectively, whereas the spatial variation of %Na, SAR, RSBC, and MH demonstrate very poor irrigation water quality, and spatial variation of KR, RSC, SSP, PI, and PS signifies that the irrigation water quality is excellent to good. In order to identify the specific association and potential source of the dissolved chemical in the groundwater, statistical techniques like correlation and principal component analysis were also employed. The hydrochemical facies indicates that mixed type makes up the bulk (51.51%) of the water samples. Following the Wilcox plot, more than 75% of the water samples are good to doubtful; however, by the US salinity hazard map, roughly 60.60% of the samples had high salinity (C3-S1 zone). The EWQII reports that no samples fall into the very good (no restriction) category, whereas 30.30%, 30.30%, and 39.40% of the sample wells record good (low restriction), average (moderate restriction), and poor (severe restriction) irrigation water quality, respectively. Based on this study, the bulk of the groundwater samples taken from the study area are unsuitable for cultivation. The findings of this study will also help decision-makers develop adequate future plans for irrigation and groundwater resource management.

Spatial variation in groundwater quality and health risk assessment for fluoride and nitrate in Chhotanagpur Plateau, India

The evaluation of groundwater quality is vital to assess the risk to human health. The present study assesses groundwater quality for drinking purposes and human health risks due to ingestion of fluoride and nitrate through drinking water in Chhotanagpur Plateau, India, using geoinformation techniques. For drinking water quality assessment, analyzed parameters were compared with World Health Organization (WHO) standards, and water quality index (WQI) was used. Results reveal that most of the samples come within the desired limit suggested by WHO. In a few samples, conductivity, hardness, chloride, sulfate, and calcium are higher than the desirable limit, whereas fluoride and nitrate are beyond the permissible limit in 70% and 27% of the samples, respectively. WQI highlights that poor to very poor water is present in 25% of the samples. Anthropogenic activities have played a critical role in deteriorating groundwater quality, resulting in harmful impacts on human health. To assess non-carcinogenic health risks, the hazard quotient (HQ) and total hazard index (THI) were computed. THI ranges from 0.01 to 7.46, 0.01 to 7.05, and 0.01 to 9.05 for males, females, and children, respectively. THI is greater than the allowable limit in 84%, 78%, and 89% of the samples for males, females, and children, respectively, indicating high risk to human health, particularly children. The study advocates proper water management strategies. Knowledge of spatial variation and anomalous concentration is vital for groundwater management as well as health risk assessment. The findings of this study will be helpful to government officials, policy planners, and local communities.

Evaluation of groundwater quality for drinking and irrigation purposes using proxy indices in the Gunabay watershed, Upper Blue Nile Basin, Ethiopia

Evaluation of groundwater potential and its quality assessment for drinking and irrigation has recently become a major concern, especially in developing countries due to various constraints. The primary aim of this study is to evaluate the quality of groundwater and establish whether they are safe for domestic and agricultural usage. 78 samples were collected during dry and wet seasons from 39 locations in the Gunabay district of the upper Blue Nile, Ethiopia. The following physicochemical parameters were evaluated successfully (T, pH, EC, TDS, Na⁺, K⁺, Ca²⁺, Mg²⁺, Fe, Cl^-, F^-, SO₄ ^2-, PO₄ ^3-, CO₃ ^2-, HCO₃ ^-, and NO₃ ^--N). Then, Entropy Weight Water Quality Index (EWQI) and irrigation water quality indices (SAR, %Na, MAR, RSC, PS, KI, PI, and IWQI) were used to assess the distribution of groundwater quality in the study area. The Piper diagram used to characterize the groundwater types revealed that Ca-HCO₃ is dominant in the area and rock-water interaction regulates the chemical characteristics of groundwater. Wilcox diagram was used to analyze the salinity level in the groundwater. The findings showed that the groundwater had higher nitrate levels relative to the permissible level of WHO standards due to excessive use of fertilizers in rural areas. Depending on the EWQI approach, the study area was categorized as excellent, good, and medium zones, covering 84.6%, 12.8%, and 2.6%, respectively. The results depict that high-quality drinking water was available in rural areas, n high to medium in the urban regions. The comparative irrigation water indices record 85% of water wells are suitable for irrigation, but some well sites are unsuitable due to higher salinity hazards and deep rock interaction. These integrated water quality indices were effective in validating drinking and irrigation water quality in the study area.

Assessment of the impact of flood on groundwater hydrochemistry and its suitability for drinking and irrigation in the River Periyar Lower Basin, India

Owing to the consequences of Anthropocene climate changes, extremes of weather and climate disasters such as heavy precipitation, tropical cyclones, and floods, have strengthened in every region across the globe and are badly affecting the earth system processes. The climate change has a tremendous impact in the Western Ghats, the UNESCO heritage site in India, and has to be studied in detail. Floods are the most common (and among the most deadly) natural disasters bringing heavy destruction in the Western Ghat river basins of India, and the Periyar basin is one among them. The low-lying areas of Periyar river basin (RPLB) is one of the worst affected river basins in the 2018 Kerala floods. Since the basin was continuously monitoring, the groundwater quality has been assessed in Periyar basin during three periods (pre-flood, flood, and post-flood-April, August, and October 2018 respectively) and is described in this paper. Since the water table is shallow in RPLB, floodwaters quickly reach the groundwater table, thus influencing the groundwater quality. So, the groundwater samples were collected from 26 sites in RPLB, and analyzed for quality determining parameters. Parameters like pH, TDS, EC, TH, NH₃^-, NO₂^-, HCO₃^-, SO₄^2-, SiO₄^4-, Mg²⁺, and K⁺ decreased during flood compared to pre-flood times. On the other hand, Ca²⁺, Na, and Cl^-, turbidity values were increased during flood times. The values of pH, TDS, EC, turbidity, NH₃^-, HCO₃^-, SO₄^2-, SiO₄^4-, Mg²⁺, Na⁺, and K⁺ were slightly increased in post-flood period compared to flood period. When compared to the pre-flood values, turbidity, NH₃^-, SO₄^2-, Na⁺, and K⁺ were slightly increased in post-flood period. It was also observed that pH, TDS, EC, TH, NO₂^-, Cl^-, HCO₃^-, SiO₄^4-, PO₄^3-, Ca²⁺, Mg²⁺, and E. coli values were higher in pre-flood periods compared to the post-flood scenario. Except pH, turbidity, and E. coli, the averages of all other parameters are falling under the recommended drinking quality values of WHO. The pH belongs to acidic nature throughout the study period. The Piper plot indicates the dominance of Ca-Mg-HCO₃ type in pre-flood, and mixing of Ca-Mg-HCO₃ type in both flood and post-flood periods. The Gibbs plot reveals that the concentration of elements is mainly depending on rock weathering and sub-surface water flow. The USSL plot depicted that the 92-96% of samples are noted as lower salinity and low sodium hazard at the source of C2S1 and C1S1; however, the 4-11% of samples are noted as high salinity but low sodium hazard at a source of C4S1 and C3S1. The Wilcox diagram indicates that the 88-96% of groundwater was found as higher suitability for irrigation during the study periods. Based on GIS based WQI model, out of the 26 samples studied, 69% of wells showed improvement in water quality after flood; meanwhile, 19% well water samples in flood were observed for lower quality compared to pre-flood times and 12% of samples remain unchanged during flood. Though floods are having positive and negative impacts, from this study, it is clear that quality of the groundwater in the RPLB is not severely affected, but they became diluted to permissible limits during flood and post-flood periods except some locations. Since the flood impact studies on groundwater systems are meager, this data from Periyar basin can be used as baseline groundwater reference data for all future flood-related river basin studies and will be very beneficial for the policy and planning needs in the context of climate change. It is high time to establish the baseline data of all river basins of Western Ghats since the normal earth system processes are worse affected by the recurrence of floods which are reporting every year.

Groundwater quality assessment for irrigation by adopting new suitability plot and spatial analysis based on fuzzy logic technique

This study was focused on identifying the region suitable for agriculture-based, using new irrigation groundwater quality plot and its spatio-temporal variation with fuzzy logic technique in a geographic information system (GIS) platform. Six hundred and eighty groundwater samples were collected during pre, southwest, northeast, and post monsoon periods. A new ternary plot was also attempted to determine the irrigation suitability of water by considering four essential parameters such as sodium adsorption ratio (SAR), permeability index (PI), Sodium percentage (Na %), and electrical conductivity (EC). The derived ternary plot was the most beneficial over other available plots, as it incorporated four parameters, and it differs from the US Salinity Laboratory (USSL) plot, such that the groundwater with higher EC could also be used for irrigation purposes, depending on the Na%. The ternary plot revealed that the groundwater predominantly manifested good to moderate category during post, northeast, and southwest monsoons. The assessment with the amount of fertilizer used during the study period showed that the NPK fertilizers were effectively used for irrigation during monsoon periods. Spatial maps on EC, Kelly's ratio, Mg hazard, Na%, PI, potential salinity (PS), SAR, residual sodium carbonate (RSC), and soluble sodium percentage (SSP) were prepared for each season using fuzzy membership values, integrated for each season. A final suitability map derived by an overlay of all the seasonal outputs has identified that the groundwater in the western and the eastern part of the study area are suitable for agriculture. The study recommends cultivation of groundwater-dependent short-term crops, along the western and northern regions of the study area during the pre-monsoon season.

Hydrogeochemical assessment of groundwater quality and suitability for irrigation in the coastal part of Cuddalore district, Tamil Nadu, India

A study was undertaken to identify in the irrigational suitability of groundwater in the cuddalore district (coastal part), Tamil Nadu, India. An entire study, 132 shallow and deep groundwater samples was gathered during Pre monsoon period (PRM) year of 2017 and post monsoon (POM) period samples collected year of 2018. Rock water interaction, silicate weathering and domestic waste are dominant sources for the water quality in the study area. The groundwater classification and irrigational suitability of groundwater were performed for both seasons. From the results of Chloro-Alkaline Indices (CAI I), and Chloro-Alkaline Indices (CAI II), during both seasons and classes, the direct ions exchange processes are predominant when compare with reverse ions exchange processes. The r₁ and r₂ results represents that most of the samples found as saline sources as Na⁺ - SO₄^2- facies and performing with Deep Meteoric Percolation (DMP) than shallow meteoric percolation During PRM season, r₁ represents 65 (98%) samples for Na⁺ - SO₄^2- facies and 1 (2%) sample represents Na⁺ - HCO₃^- facies and during POM season, r₁ represents 63 (95%) samples for Na⁺ - SO₄^2- facies and 3 (5%) samples represent Na⁺ - HCO₃^- facies respectively. Irrigation water quality parameters like and satisfied the analysed water's irrigation suitability. However, according to MAR parameters, 5% of water samples were unsuitable for irrigation in PRM based on KR parameters, 41% of samples collected in the PRM season only were unsuitable for irrigation. The Wilcox diagram showed that 35% of water samples are suitable for irrigation. Sodium Adsorption Ratio (SAR), Soluble Sodium Percentage (SSP), Magnesium Adsorption Ratio (MAR), Permeability Index (PI), Potential Salinity (PS), and Total Dissolved Solids (TDS) are indicating the irrigational appropriateness of the groundwater samples, which is more suitable in post monsoon season compare to pre monsoon due to enrichment of Na⁺ by seawater intrusion and other processes. During POM season, the most number of groundwater samples are representing excellent to good categories might be due to an effective rainfall recharge by the monsoonal rain in the study area. The parameters indicated the introduction of geogenic and anthropogenic pollutions. The coastal community's knowledge is crucial to the long conservation of coastal water resources.

Groundwater Quality Issues and Challenges for Drinking and Irrigation Uses in Central Ganga Basin Dominated with Rice-Wheat Cropping System

Increased population and increasing demands for food in the Indo-Gangetic plain are likely to exert pressure on fresh water due to rise in demand for drinking and irrigation water. The study focuses on Bhojpur district, Bihar located in the central Ganga basin, to assess the groundwater quality for drinking and irrigation purpose and discuss the issues and challenges. Groundwater is mostly utilized in the study area for drinking and irrigation purposes (major crops sown in the area are rice and wheat). There were around 45 groundwater samples collected across the study region in the pre-monsoon season (year 2019). The chemical analytical results show that Ca2+, Mg2+ and HCO3− ions are present in abundance in groundwater and governing the groundwater chemistry. Further analysis shows that 66%, 69% and 84% of the samples exceeded the acceptable limit of arsenic (As), Fe and Mn respectively and other trace metals (Cu, Zn, Pb, Cd) are within the permissible limit of drinking water as prescribed by Bureau of Indian Standard for drinking water. Generally, high As concentration has been found in the aquifer (depth ranges from 20 to 40 m below ground surface) located in proximity of river Ganga. For assessing the irrigation water quality, sodium adsorption ratio (SAR) values, residual sodium carbonate (RSC), Na%, permeability index (PI) and calcium alteration index (CAI) were calculated and found that almost all the samples are found to be in good to excellent category for irrigation purposes. The groundwater facie has been classified into Ca-Mg-HCO3 type.

Assessment of surface and groundwater quality for irrigation purposes in the Danube-Tisa-Danube hydrosystem area (Serbia)

The study evaluates irrigation water quality in the Danube-Tisa-Danube hydrosystem area (Vojvodina, northern Serbia). The area is dominantly a plain with about 75% arable land, suitable for agricultural production and irrigation. Use of water of inadequate quality can have long-term effects on irrigated land and affect the yield of cultivated crops. The analyses included data from 40 surface water and 23 groundwater quality monitoring locations, observed during the period 2013-2018. The average annual values of the concentrations of major cations and anions and of electrical conductivity in surface and groundwater were comparatively analyzed. These values were statistically significantly higher (by p < 0.05) in groundwater bodies with most of the analyzed parameters. Hydrochemical classification of water types shows that 95% of surface and 87% of groundwater locations belong to the Ca·Mg-HCO₃ water type. Water suitability for irrigation was assessed using specific parameters and indices (sodium adsorption ratio, Na%, residual sodium carbonate, magnesium hazard, permeability index, and Kelly's index). The results showed that surface and groundwater resources are generally of good quality and suitable for irrigation, with sporadic deviations at several locations. The principal component analysis (PCA) was used to identify the most important variables affecting the chemical composition of the analyzed waters and group the monitoring locations by their chemical characteristics. The spatial variation of the analyzed water quality indices was shown on thematic maps.

Heavy metals pollution indexing, geospatial and statistical approaches of groundwater within Challawa and Sharada industrial areas, Kano City, North-Western Nigeria

Abstract

The present study focused on pollution status of groundwater in the industrial areas of Challawa and Sharada in Kano city based on pollution indices, statistical and spatial analyses. Twenty groundwater samples representing groundwater of the studied areas (Ten from each area) were analyzed for the presence of Cd, Cr, Ni, Fe, Mn and Zn using atomic absorption spectrophotometer. The result showed 95%, 5%, 60%, 15% and 25% of the analyzed water samples had detectable Cd, Cr, Ni, Fe, and Mn above the drinking water limits of both Nigerian standards for drinking water quality NSDWQ and World Health Organization (WHO) with Cd dominating other analyzed heavy metals in the groundwater. Evaluation of heavy metal pollution revealed a low polluted status based on the contaminant index (Cd), synthetic pollution index, heavy metals evaluation index, and heavy metal pollution index. Metal index categorized the groundwater as seriously polluted. The statistical evaluation gave strong and positive correlations between indices and a moderate one between the metallic ions. Component analysis revealed a strongly positive loading of Fe, Ni and Zn while Cd had a strong negative loading. Cr and Mn were positive and moderately loaded. Statistical analyses suggested both anthropogenic and geogenic sources for the heavy metals mainly from the industrial and agricultural practices and rock weathering processes, respectively. This study is expected to be a useful tool in the planning, monitoring and mitigation of pollution activities in the area.

Article Highlights

Groundwater pollution index (GPI) and GIS-based appraisal of groundwater quality for drinking and irrigation in coastal aquifers of Tiruchendur, South India

We assessed groundwater pollution index (GPI) and groundwater quality of coastal aquifers from Tiruchendur in South India for drinking and irrigation by evaluating the physico-chemical parameters of 35 samples of mainly Na-Cl type in an area of 470 km² with respect to the World Health Organization (WHO) standard as well as by estimating different indices such as total hardness (TH), sodium percentage (Na%), magnesium ratio (MR), Kelley's ratio index (KR), potential salinity (PS), Langelier saturation index (LSI), residual sodium carbonate (RSC), sodium adsorption rate (SAR), permeability index (PI), and the irrigation water quality index (IWQI). Minimal influence of aquifer lithology and the dominant influence of evaporation on groundwater chemistry reflected the semi-arid climate of the study area. Electrical conductivity (EC) of about 89% of the samples across 418 km² exceeded the permissible limit and Ca values of 74% of samples, however, remained within the allowable limit for drinking. More chloride was caused by influx of seawater and salt leaching and higher K was due to excessive fertilizer usage for agriculture. The spatial distribution map created using inverse distance weighting (IDW) method shows that the suitable groundwater is present close to the river basin. GPI values between 0.40 and 4.7, with an average of 1.5, classify insignificant pollution in 43% of the study region and the groundwater suitable for drinking purposes. In addition, 17% of the groundwater samples are also marginally suitable for drinking. The irrigation water quality indices provided contradictory assessments. Indices of TH, Na%, MR, PS, and LSI suggested 32-95% of the samples as unsuitable for irrigation, whereas the indices of RSC, SAR, and PI grouped 72-100% samples as permissible for irrigation. The IWQI map, however, indicated that the groundwater from more than half of the study area are not apt for irrigation and the groundwater of about one-third of the area could only be applied to salt-resistant plants.

Geochemical, Geological and Groundwater Quality Characterization of a Complex Geological Framework: The Case Study of the Coreca Area (Calabria, South Italy)

Hydrogeochemical characterization and statistical methods were used to investigate the groundwater quality and the origin of constituents (anthropic or natural) in groundwater of the Coreca area (Calabria, South Italy). Coreca is characterized by an articulated geological setting where the three main geological complexes that distinguish the Northern Calabria Peloritan Orogen (CPO) outcrop. This complex asset affects the quality of groundwater mainly exploited for irrigation use. In particular, the presence of ultramafic rocks (e.g., serpentinite and metabasite) promotes the release of harmful elements such as Cr and Ni. In the studied area, two groups of waters were identified: Ca-HCO3 waters strongly controlled by the interaction with Ca-rich phases (e.g., limestone), and Mg-HCO3 waters related to the interaction of meteoric water with the metamorphic units. Statistical elaboration allowed to detect, in the Mg-HCO3 group, a good correlation between Cr and Ni (not observed in Ca waters) and a negative correlation between Cr, Ca and Al, in agreement with direct interaction with ultramafic rocks characterized by low concentrations of CaO and Al2O3. The concentration of major and trace elements has been compared with the Italian law limit values and the drinking water guidelines provided by the World Health Organization (WHO). Only three samples showed Mn and Ni concentration higher than the Italian law threshold. Furthermore, the assessment of groundwater quality was carried out using salinity and metal indexes. The groundwater quality assessment for irrigation allowed to classify the resource as “excellent to good” and “good to permissible”; nevertheless, a salinity problem and a magnesium hazard were found. Lastly, a metal index (MI) calculation revealed values <1 for almost all samples, pointing to good overall quality. Only a few samples showed a value extremely higher than 1, attributable to prolonged interaction with ultramafic rocks and/or localized anthropogenic pollution. From a general point of view, groundwater showed a generally good quality except for limited areas (and limited to the set of constituents analyzed) and a mild exceedance of the maximum salinity thresholds that must be monitored over time. Through a multidisciplinary approach, it was possible to ascertain the main anomalies attributable to the interaction with the hosting rocks and not (with few exceptions) to anthropic processes.

The Integration of Multivariate Statistical Approaches, Hyperspectral Reflectance, and Data-Driven Modeling for Assessing the Quality and Suitability of Groundwater for Irrigation

Sustainable agriculture in arid regions necessitates that the quality of groundwater be carefully monitored; otherwise, low-quality irrigation water may cause soil degradation and negatively impact crop productivity. This study aimed to evaluate the quality of groundwater samples collected from the wells in the quaternary aquifer, which are located in the Western Desert (WD) and the Central Nile Delta (CND), by integrating a multivariate analysis, proximal remote sensing data, and data-driven modeling (adaptive neuro-fuzzy inference system (ANFIS) and support vector machine regression (SVMR)). Data on the physiochemical parameters were subjected to multivariate analysis to ease the interpretation of groundwater quality. Then, six irrigation water quality indices (IWQIs) were calculated, and the original spectral reflectance (OSR) of groundwater samples were collected in the 302–1148 nm range, with the optimal spectral wavelength intervals corresponding to each of the six IWQIs determined through correlation coefficients (r). Finally, the performance of both the ANFIS and SVMR models for evaluating the IWQIs was investigated based on effective spectral reflectance bands. From the multivariate analysis, it was concluded that the combination of factor analysis and principal component analysis was found to be advantageous to examining and interpreting the behavior of groundwater quality in both regions, as well as predicting the variables that may impact groundwater quality by illuminating the relationship between physiochemical parameters and the factors or components of both analyses. The analysis of the six IWQIs revealed that the majority of groundwater samples from the CND were highly suitable for irrigation purposes, whereas most of the groundwater from the WD can be used with some limitations to avoid salinity and alkalinity issues in the long term. The high r values between the six IWQIs and OSR were located at wavelength intervals of 302–318, 358–900, and 1074–1148 nm, and the peak value of r for these was relatively flat. Finally, the ANFIS and SVMR both obtained satisfactory degrees of model accuracy for evaluating the IWQIs, but the ANFIS model (R2 = 0.74–1.0) was superior to the SVMR (R2 = 0.01–0.88) in both the training and testing series. Finally, the multivariate analysis was able to easily interpret groundwater quality and ground-based remote sensing on the basis of spectral reflectance bands via the ANFIS model, which could be used as a fast and low-cost onsite tool to estimate the IWQIs of groundwater.

Combining Hydrogeochemical Characterization and a Hyperspectral Reflectance Tool for Assessing Quality and Suitability of Two Groundwater Resources for Irrigation in Egypt

Hyperspectral reflectance sensing provides a rapid and cost-effective technique for assessing the suitability of groundwater for irrigation by monitoring real-time changes in its quality at a large scale. In this study, we assessed the quality of 15 groundwater samples from El Fayoum depression in the Western Desert (WD) and 25 groundwater samples from the Central Nile Delta (CND) in Egypt using a traditional approach of the physiochemical parameters, irrigation water quality indicators (IWQIs), and hydrochemical facies. The spectral reflectance data of the water surface was used to build new simple reflectance indices (SRIs), and the performance of these indices for assessing IWQIs was compared with those by partial least square regression (PLSR) that was based on all SRIs or the full-spectrum ranges. Generally, the groundwater of the CND was fresher and more suitable for irrigation purposes than those of the WD. Based on the six IWQIs, ~6.7–60.0% and 85.0–100.0% of the groundwater samples of the WD and CND, respectively, were categorized as highly suitable for irrigation purposes. Based on hydrochemical facies, Na-Cl and Ca-HCO3 were dominant in the WD and CND, respectively, as well as the alkali earth metals (Na+ + K+), which significantly exceeded the alkaline earth metals (Ca2+ + Mg2+) in the WD, with the reverse for the CND. Most developed SRIs had a moderate, weak, and moderate to strong relationship with physiochemical parameters and IWQIs in the WD, CND, and across both regions, respectively. The PLSR models based on all SRIs provided a more accurate estimation of IWQIs in calibration and validation datasets than those based on full-spectrum ranges, and both PLSR models provided better estimation than the individual SRIs. These findings support the feasibility of using ground reflectance measurements as a fast and low-cost tool for the assessment and management of groundwater for irrigation in arid and semiarid regions.

Application of water quality index, synthetic pollution index, and geospatial tools for the assessment of drinking water quality in the Indus Delta, Pakistan

Seawater intrusion into the Indus Delta, Pakistan, has spoiled groundwater aquifers in the area. In the delta, the groundwater is widely used by residents for drinking. Considering the gravity of the problem, and concerns expressed by affected communities, the present study was conducted to assess and map the quality of groundwater, based on the physico-chemical properties of 180 samples, using two standard numerical indices, geospatial and statistical techniques. The analysis of water samples revealed that several parameters exceeded the drinking water quality guidelines suggested by the World Health Organization (WHO). The water quality index (WQI) identified that about 1.7%, 1.1%, 27.8%, 42.8%, and 26.6% of the water samples were excellent, good, poor, very poor, and unsuitable for drinking purposes, respectively. However, the synthetic pollution index (SPI) ranked the quality of 2.8%, 2.2%, 23.9%, 41.7%, and 29.4% as suitable, slightly polluted, moderately polluted, highly polluted, and unsuitable, respectively. Though the numerical model's input is different, the proportionate ranking revealed a fair correlation (R² = 0.75) between the outcomes of both indices. The results of the numerical indices and the interpolated geographical information system (GIS) mapping revealed that the quality of groundwater in most of the delta does not meet WHO guidelines for potable water. Hence, it is recommended that the groundwater of the delta should be properly treated before its use for domestic purposes. The study highlights the significance of using numerical indices and geospatial techniques for water quality evaluation in the Indus Delta and similar deltaic regions throughout the world.

Hydrochemical characteristics and irrigation suitability of surface water in the Syr Darya River, Kazakhstan

The surface water hydrochemistry of the Syr Darya River in Kazakhstan was investigated at 39 locations to analyze regional hydrochemical characteristics and evaluate the irrigation suitability of the studied regions. The cations in the surface water are mainly Na⁺, Ca²⁺, and Mg²⁺, while the anions are mainly SO₄^2-. The main hydrochemical type is Ca-Mg-SO₄-Cl. From the perspective of natural factors, the hydrochemical characteristics in the study area are derived from the dual effects of rock weathering and evaporation-concentration; however, the influence of anthropogenic factors include industrial and agricultural production near the river and the inflow of urban domestic sewage on the hydrochemical characteristic is also present. The irrigation suitability evaluation of the surface water based on SAR, Na% and KI showed that the majority of the water is suitable for irrigation, and from the TDS content analysis, 71.43% of the samples are in a critical state, indicating that the influence of TDS concentration on irrigation suitability cannot be ignored. The results have practical significance for maintaining the sustainable use of water resources in the Syr Darya River.

Effects of groundwater metal contaminant spatial distribution on overlaying kriged maps

Groundwater is a major source of drinking water for many Canadians, and contamination by heavy metals poses a significant risk to people and the environment. In this study, three water quality indices are studied in the vicinity of an unlined landfill in a semiarid climate. The study investigates indices using geostatistical analysis and ordinary kriging. This study employs a novel coupling technique in order to compare the index-based maps to a groundwater quality map from overlapping heavy metal kriged maps. A total of 11 heavy metals were evaluated in preliminary analysis, but only four (Mn, As, Fe, and U) had higher concentrations than allowable limits in some or all of the monitoring wells at the site. Results from mean-based classification of indices suggest the aquifer in proximity to the landfill has been impacted by metal contaminants. Kriged maps show that the spatial variations of Mn and U are similar, while results of Fe and As are also similar. However, the two sets of maps have distinctly different patterns. Maps for indices show an elevated plateau extending from the unlined landfill to the southeast corner, implying that the landfill may have negatively impacted groundwater quality. A groundwater quality map is developed by overlaying the heavy metal maps. The resulting map shows that the north and west parts of the study have lower groundwater pollution with respect to metal contaminants. The groundwater quality map may be more applicable for practitioners who need comprehensive water quality measurement.

Seasonal dynamics of phytoplankton population and water quality in Bidoli reservoir

Seasonal water quality analysis helps to evaluate the impact of anthropogenic activities on reservoirs. The water quality may be judged by estimating various chemical parameters like dissolved oxygen (DO), free CO₂, total alkalinity, total hardness, pH, Ca⁺⁺, Mg⁺⁺, Cl^-, NO₃^-, SO₄^- bicarbonate, and total dissolved solids (TDS) along with environmental parameters like rainfall and temperature. Most of these abiotic factors are subject to human interventions and are interrelated. This cumulative effect directly influences the biota of the reservoir ecosystem where plankton communities are significant. The current work was carried out with the goal to understand the effect of abiotic factors on planktonic growth in a medium-sized artificial reservoir. The study was attempted to analyze two objectives, which were the variations of parameters with respect to three distinct seasons encountered in the region (summer, monsoon, and winter) and second being the impact of such varying parameters on countable/detectable planktonic diversity. From the water samples collected, 44 genera of planktons belonging to Cyanophyceae, Chlorophyceae, Dinophyceae, Desmids, Bacillariophyceae, and Euglenozoa were identified. There was a marked variation in the seasonal parameters pH, EC, temperature, CO_2, and HCO₃^-. Comparison to the BIS and WHO values shows that though water is not potable, it can be used for agriculture and fishing. Thus, it is necessary that this predominantly rainfed reservoir be maintained for sustainable use.

In situ phytoremediation of copper and cadmium in a co-contaminated soil and its biological and physical effects

Phytoremediation is a potential cost-effective technology for remediating heavy metal-contaminated soils.

Estimation of Heavy Metal Contamination in Groundwater and Development of a Heavy Metal Pollution Index by Using GIS Technique

Heavy metal (Al, As, Ba, Cr, Cu, Fe, Mn, Ni, Se and Zn) concentration in sixty-six groundwater samples of the West Bokaro coalfield were analyzed using inductively coupled plasma-mass spectroscopy for determination of seasonal fluctuation, source apportionment and heavy metal pollution index (HPI). Metal concentrations were found higher in the pre-monsoon season as compared to the post-monsoon season. Geographic information system (GIS) tool was attributed to study the metals risk in groundwater of the West Bokaro coalfield. The results show that 94 % of water samples were found as low class and 6 % of water samples were in medium class in the post-monsoon season. However, 79 % of water samples were found in low class, 18 % in medium class and 3 % in high class in the pre-monsoon season. The HPI values were below the critical pollution index value of 100. The concentrations of Al, Fe, Mn, and Ni are exceeding the desirable limits in many groundwater samples in both seasons.