Groundwater Hardness Research Articles

Effectiveness of electrochemical softening for removing hardness in real groundwater

Effectiveness of electrochemical softening for removing hardness in real groundwater

Causes and Effects of Scale Deposition in Water Supply Pipelines in Surakarta City, Indonesia

Globally, scale deposition in water supply pipelines is one of the major problems faced by water utilities. This research aimed to determine the causes and effects of scale deposition in the water supply pipelines in Surakarta City, Indonesia. The total dissolved solids (TDS), hardness, manganese, and alkalinity in groundwater were higher than those in the surface water and spring water; thus, the supply areas from groundwater were identified using TDS at the taps. The three scaling indicators, i.e., the Langelier saturation index (LSI), the Ryznar stability index (RSI), and the Puckorius scaling index (PSI), indicated moderate calcium carbonate scaling. However, elemental analysis of eight scale samples using X-ray fluorescence (XRF) revealed that the major components of scale were either manganese (50.1–80.8%) or iron (45.6–63.8%), whereas calcium (3.0–7.8%) was a minor component. Because only five of twenty groundwater sources were chlorinated before distribution, it is estimated that dissolved manganese is oxidized by manganese-oxidizing bacteria. The manganese deposition rate in the networks was estimated to be 1660 kg/year using the manganese concentration at groundwater sources and in customers’ taps. These results suggest the importance of the elemental analysis of scale and avoidance of overreliance on scale indicators.

Phreatic Groundwater Quality Analysis Based on Physical and Chemical Parameters in Kuta Raja Sub-District

Phreatic groundwater, discovered easily around communities in the Kuta Raja Sub-district, is sourced from the subsurface and stored in saturated areas, where it flows naturally through seepage or jets. Therefore, this study aimed to analyze the quality of phreatic groundwater using physical and chemical parameters. Color, taste, smell, and temperature were the physical parameters analyzed, while chemical parameters tested included electrical conductivity value, acidity (pH), and hardness level. To conduct the experiment, a total of 50 samples were obtained using a random sampling method. Physical parameters were evaluated using the observational method. Test for groundwater hardness level was conducted at the Aceh Health Office's Health & Medical Equipment Testing Laboratory. The pH was measured using a pH meter, while electrical conductivity value and phreatic groundwater temperature were tested using a water quality checker. The results showed that the physical quality of groundwater was in good condition. Approximately 64% of the samples had characteristics of yellow, tasteless, and odorless. The temperature value was in the medium category (30°C-35°C). Additionally, the electrical conductivity value of 84% was in the medium class (1,200–2,500) brackish groundwater category. It was important to acknowledge that a groundwater pH value of 6.5–8.5 based on field measurements was in the normal class. The hardness level (CaCO3) of phreatic groundwater was evaluated using the Titrimetric method based on SNI Number 06-6989.12-2004. The test was conducted on 6 groundwater samples in terms of water flow and variations in electrical conductivity values. Based on observations, 4 samples were categorized as "hard" samples, while 2 were classified as “very hard”.

A pragmatic approach of hydrochemical and irrigation indices of groundwater quality of district Ballia, U.P. India

ABSTRACT In the groundwater aquifer media, enormous amounts of ions can be found naturally in rocks from the Pleistocene and Holocene ages. There are several reports of metals and ionic contamination in the different blocks of the Ballia district. This article focuses on a thorough investigation of the hydrogeochemical properties and the cause of ionic contamination in the Ballia district's groundwater system. This article discusses the interactions between the numerous cations and anions that are hydro-geologically present as well as several physico-chemical factors. The relationship analysis was conducted utilizing irrigation indices and a Stufzand classification, which was further supported by a Durov and Stiff plot. The Durov plot shows the mineralization of the aquifer by sand and evaporates of geological formation. The Gibbs plot shows that the rock–water interaction, weathering of silicates, evaporates dissolution, carbonate dissolution, and anthropogenic activities. The Stiff plot shows the highest concentration of Mg-rich minerals and Cl due to the weathering of calcite, amphiboles, and anthropogenic activities also proven by the Irrigation indices and Stufzand classification. The high water quality index (WQI) value was discovered to be mostly due to greater EC, total dissolved solids, hardness, nitrate, sulfate, chloride, and magnesium levels in groundwater.

Modeling the total hardness (TH) of groundwater in aquifers using novel hybrid soft computing optimizer models

Modeling the total hardness (TH) of groundwater in aquifers using novel hybrid soft computing optimizer models

Groundwater Hardness and Alkalinity As Risk Factors for Kidney Stone Disease in Alwar, India: An Ecological Study.

Rajasthan is a semi-arid state in India where people still use groundwater for drinking purposes. However, the quality of groundwater as compared to standards have not been studied in any details. This ecological study was done to study the groundwater quality parameters in the stone-belt states, compare the quality of groundwater in Alwar with the rest of Rajasthan, and study the morbidity profile of surgical in-patients in the same district, with special emphasis on kidney stone disease (KSDs). The morbidity profile of patients coming to the surgery department of a tertiary teaching hospital between January 2002 and June 2023 was obtained from the medical records department, and water quality data was obtained from the publicly available Water Resources Information System (WRIS) groundwater dataset for the year 2023. The dataset provided detailed information on the chemical parameters of water samples throughout the country that were evaluated to estimate the quality of groundwater. It was found that the groundwater in Alwar is non-potable due to the presence of iron, alkalinity, magnesium, and total dissolved solids (TDS). Iron was estimated to be much higher than the acceptable limit of the Bureau of Indian Standards (BIS) drinking-water quality guidelines (0.3 mg/L). Similarly, most of the chemical parameters in the groundwaters of Rajasthan significantly exceeded the national average. The median electrical conductivity, fluoride, magnesium, sodium, hardness, alkalinity, and turbidity were found to be 1680 μS/cm, 1.05 parts per million (PPM), 41 PPM, 233 PPM, 330 PPM, 310 PPM, 988 PPM, respectively, which are above the WHO recommendations for drinking water guidelines. The levels of iron and total alkalinity were significantly higher in the study district as compared to the rest of the state. Also, magnesium hardness and TDS levels were very high in the groundwater of the entire state of Rajasthan, making the population vulnerable to KSDs in the long run.

Analysis of the chemical characteristics and causes of high total hardness of groundwater in Jianghan Plain, China.

Familiarity with the chemical characteristics of regional groundwater can provide important guidance and reference for the development of regional groundwater exploitation. Jianghan Plain has been reported to have high groundwater total hardness (TH), resulting in the inability of local groundwater to be directly used as drinking water. In order to explore the causes of high TH, the paper analyzed the hydrochemical characteristics of shallow groundwater in Jianghan Plain combined with software of SPSS, JMP, and PHEEQC. The results showed that the cations in the groundwater in the area were mainly Ca2+, while the anions were mainly HCO3-. 20% of groundwater exceed the China national guideline for TH (i.e., 450mg/L). The groundwater chemistry in the study area was controlled by three main factors of dissolution of carbonate rocks, human activities, and redox conditions, among which the interaction between water and rock had the greatest impact. The water carbonate rock interaction within Jianghan Plain was affected by various factors such as water flow and aquifers and showed a gradually weakening trend from west to east. This work not only strengthened the understanding of the causes of the high TH of groundwater in the region, but also provided reference value for regional groundwater environmental management.

Chemical Characteristics of Shallow Groundwater in the Yellow River Diversion Area of Henan Province and Identification of Main Control Pollution Sources

The northern plain of Henan in the lower reaches of the Yellow River is an area where the Yellow River is frequently diverted. The shallow groundwater quality in this area is poor， and many types of components have been found to be exceeding the limit value； however， the contribution of various environmental factors to water quality needs to be further quantified. In order to clarify the genesis of water quality of shallow groundwater in the study area， 330 groups of shallow groundwater samples were collected via a regional water quality survey. The evolution of shallow groundwater quality in the Yellow River diversion area of northern Henan was revealed using the principal component-absolute principal component score-multiple linear regression （PCA-APCS-MLR） model. The results showed that the components with a shallow groundwater excess rate greater than 10% in descending order were manganese， iron， total hardness， total dissolved solids， sodium， fluoride， arsenic， chloride ions， sulfate， and ammonium. In particular， the excess rate of manganese reached 76%. The four factors of dissolution enrichment， native origin of soil， redox conditions， and agricultural activities were identified as the main reasons for poor groundwater quality， which accounted for 71.24% of the cumulative interpretation rate of variance. In addition， the recharge from the surface water also influenced the groundwater quality. The effects of dissolution between the water and aquifer matrix and redox condition in the aquifer of the Yellow River dried-riverway like Xinxiang were significantly enhanced， resulting in the increasing concentration of iron， arsenic， total hardness， TDS， and other components in groundwater. Fluoride enrichment was caused by dissolution enrichment， the origin of the soil， and lateral replenishment of the Yellow River. Groundwater with high manganese concentration was widely affected by the soil matrix. Nitrate pollution of the groundwater was caused by the extensive use of chemical fertilizers in agricultural activities in individual areas.

Hydrochemical Characteristics and Genesis Mechanism of Groundwater in the Dry Period in the Zhangjiakou Area

In order to better support the construction of the capital water conservation functional area and ecological environment support area， research on the chemical characteristics of groundwater and its formation mechanism in the dry period in the Zhangjiakou area can provide a great reference for the rational development and utilization of groundwater resources. A total of 41 groups of groundwater samples were collected， and the hydrochemical types， composition characteristics， and control factors of groundwater in the study area were analyzed by using the combined method of descriptive statistical analysis， Piper triplot， correlation analysis， Gibbs plot， and ion ratio. The results showed that the groundwater in the study area was weakly alkaline， with the total hardness and ρ（TDS） ranging from 105.00 mg·L-1 to 1 433.00 mg·L-1 and 137.00 mg·L-1 to 2 286.00 mg·L-1， respectively. The total hardness and TDS mass concentrations of groundwater in the Bashang area were higher than those in the Baxia area. HCO3- and Na+ were the main dominant anions and cations in the groundwater in the study area. The highest overstandard rate of the main components in groundwater was that of total hardness （36.59%）. The overstandard rate and maximum excess multiple of each component in groundwater in the Bashang area were greater than those in the Baxia area. HCO3-Ca·Mg·Na was the main type of groundwater hydrochemistry in the study area， and there was little difference between the Bashang area and the Baxia area. SO42-， Cl-， HCO3-， Na+， and Mg2+ contributed the most to TDS. The chemical characteristics of groundwater were affected by weathering and filtration of rock minerals such as salt rock， albite， and dolomite； cation exchange； and human activities. Evaporative crystallization and atmospheric precipitation contributed to a small part of the main ion source of groundwater in the area. The effect of human activities on groundwater in the Bashang area was greater than that in the Baxia area， and NO3- mainly originated from agricultural activities.

Challenges Ahead in Groundwater of Sri Lanka

Groundwater has been a safe water storage in Sri Lanka throughout history and the unique characteristics of different aquifers impact variation of the water quality. However, due to population growth, unplanned urbanization, intensive agriculture, improper waste management, etc., the groundwater quality is considered unsafe. Therefore, it is important to refer to the available data related to the groundwater quality of Sri Lanka. Saltwater intrusion is a considerable factor in shallow karstic aquifers and as a result, relatively higher electrical conductivity, water hardness, total alkalinity, and higher anions concentrations (chloride, sulfate) were observed in the Jaffna area. The dry zone including Padaviya and Hambanthota shows relatively higher water hardness and fluoride in groundwater. Nitrate concentration is also a considerable factor, especially in the Jaffna and Padaviya areas may be due to intensive agriculture. Identification of groundwater recharge zones, recharge estimates, continuous monitoring of groundwater quality, vulnerability mapping of aquifers, and proper planning of urbanization have been identified as challenges ahead in groundwater of Sri Lanka and it is essential to include those items in the National Water Policy in Sri Lanka.

Komposit Zeolit-Polivinil Alkohol sebagai Adsorben untuk Menurunkan Kesadahan Air Tanah

Granular zeolite-polyvinyl alcohol (PVA) composites without glutralaldehyde and zeolite-PVA composites with the addition of glutaraldehyde were carried out in this study and used as adsorbents. This study aims to reduce groundwater hardness, determine the optimum zeolite size in composite mixtures, and determine the characterization of functional groups in composites. The stages of the research included: preparation and activation of zeolite with variations in zeolite sizes of 100, 60 and 45 mesh and variations in composition of zeolite-polyvinyl alcohol 1:1; 1:2; 2:1; 2:3 and 3:2. Furthermore, the preparation of PVA solution concentration of 9% and the formation of the composite. The results showed that the optimum size of the zeolite on the composite without glutaraldehyde was 60 mesh with a decrease in hardness of 68% while the ratio of the optimum zeolite-PVA composition was at a ratio of 3:2 with a decrease in hardness of 34 mg/L. The results of Langmuir and Freundlich isotherm analysis showed the presence of chemical bonds because the determination value (R2) of the adsorption isotherm was > 0.9. The results of functional group characterization showed OH- in the zeolite-PVA composite without glutaraldehyde at a wavelength of 3363.01 cm-1 while in the composite with glutaraldehyde at a wavelength of 3345.89 cm-1. The C=C functional group appeared at a wavelength of 1628.73 cm-1 for the zeolite-PVA composite without glutaraldehyde and 1635.86 cm-1 for the composite with glutaraldehyde. At a wavelength of 788.70 cm-1 and 794.40 cm-1, the Si-O symmetric stretching vibrations show in the zeolite structure.

Impact of dairy farms on groundwater quality in a productive basin in the northeast of the Pampean Plain, Argentina

The Pampean Plain is a relevant world food production area where livestock and agricultural activities are developed. The northeast of this region is characterized by dairy production, where large quantities of excreta from the animals to the substrate cause environmental impacts associated with soil and groundwater contamination. On these dairy farms, the same water sources are used for animal nutrition, cleaning of facilities, and home consumption by rural workers. Groundwater quality assessment is therefore crucial to guaranteeing safe production and human supply. The aim of this work is to analyse the impact of family dairy farming on the geochemical processes that govern the groundwater quality of aquifers used for domestic and animal consumption in productive basins of the northeast Pampean Plain. An analysis of major ions, nitrates, and phosphates in groundwater was performed in 42 wells sampled at different periods. Also, sediments in diverse sectors were collected to be analysed for available phosphorus. The main point sources of contamination that were identified derive from farm facilities’ cleaning and the degradation of animal excrement. These sources infiltrate toward the unsaturated zone and reach the groundwater, or they directly enter through poorly constructed perforations. This produces reactions in the unsaturated zone, releasing protons and generating the dissolution of carbonates, increasing the groundwater hardness. The chemical compounds registered may produce limitations in water quality for human consumption and the development of agricultural activities, affecting animal nutrition and the production of a dairy basin in the northeast of the Pampean Plain.

Demystifying the decadal shift in the extent of groundwater in the coastal aquifers of Gujarat, India: A case of reduced extent but increased magnitude of seawater intrusion

Catastrophic increase in urbanisation and industrialisation along the coastal region leads to increased stress on groundwater reservoirs worldwide. As a growing economy, India faces extreme water crises due to rising water demand and escalating salinisation, specifically in the coastal districts. Therefore, this study shows the implication of a comprehensive modelling approach to assess the spatiotemporal changes in hydrogeochemical processes in the coastal aquifer of the Surat district. Using a multi-model assessment approach, the present study focuses on the decadal evolution in groundwater quality of the coastal aquifers of Surat, Gujarat. Fifty-one groundwater samples were collected for 2008, 2012, and 2018 to assess the spatio-temporal shift in groundwater quality. Piper diagram revealed a shift of hydrogeochemical facies from Mg2+-HCO3− type to Ca2+-Mg2+-Cl− type, indicating the increased salinisation over a decade. The result suggests that rock-water interaction, seawater intrusion mechanism, and anthropogenic activities (intensive agricultural activities and improper waste management) govern the hydrogeochemical processes in the coastal aquifer. A shift of dominance of carbonate weathering to silicate weathering with the dissolution of calcite, dolomite, and gypsum, changing the hydrogeochemistry, was observed over the last decades. This shift leads to the increasing hardness of groundwater. The enrichment of nutrients in groundwater during 2018 (NO3− = 2 to 85 mg. L−1) compared to 2008 (NO3− = 1 to 36 mg.L−1) indicates the increasing imprints of agricultural fertilizer application and human organic waste through sewage contamination on the coastal aquifer. The seawater mixing index model demonstrates that extent of seawater intrusion reduced in 2018 compared to 2012, but the magnitude increased near the coastal talukas (SMI =9.5). The present study helps to understand the increasing anthropogenic activities over a decade leading to increased salinisation and groundwater contamination in the aquifer system. This work can help local stakeholders, water resource managers, and the state government manage the groundwater resources and the future potential threat of aquifer contamination.

Treatment of water using Arc discharge plasma in Patan area

The quality of drinking water has been degraded and declining day by day and its impact is directly seen on human health and other organisms too. So, the way we want to solve this problem by using new technology which was not based on the Plasma Treatment. Plasma based technology which is one of the best and new technology it takes a short time for improvement of water quality. Water sample collected from various sources within Patan from different sources such as Jar water, Ground water, Tap water and Stone spout water. The concentration of ammonia in the Jar and Tap water increased at 10 seconds after the sample was treated with Plasma. The hardness of groundwater increased significantly in all time periods as compared to without treatment. Overall, the hardness of Tap water decreased when treated with Plasma. But in case of Stone Spout water, hardness increased during 5 and 15 seconds whereas it decreased at 10 seconds. The concentration of Chloride only decreased in case of Jar water whereas there was a significant increase in its amount in all other remaining samples in each time factors i.e., 5,10,15 seconds. By using this technology water quality can be improved within short time.

Исследование многолетней динамики органолептических рисков здоровью населения волгоградского Заволжья, формируемых подземными водами, с использованием дистанционного зондирования

The paper considers the potential of using remote sensing methods in assessing the risks of olfactory effects in the population regularly drinking water from shallow underground sources vulnerable to climatic factors. The Volgograd Trans-Volga region, located on the territory of the Caspian lowland, is a typical representative of ardidized territories with highly mineralized groundwater. The xerophytic wormwood-fescue-feather-grass and solonetzic vegetation characteristic of the region determines the effectiveness of using the NDMI indicator to assess the degree of influence of soil aridity on the growth of hardness and total iron content in groundwater. A high degree of closeness of correlations between dependent indicators of the sanitary and hygienic quality of groundwater for drinking purposes and NDMI values in five-year dynamics for all groundwater basins (regions) of the North Caspian province was found. The data obtained can be useful in predicting and managing the risks of reflex-olfactory effects in consumers of water from underground sources in the organization of water supply and water treatment. Keywords: ORGANOLEPTIC RISK, NDMI, GROUNDWATER, HYDROGEOCHEMISTRY, ARIIDIZATION, HARDNESS, IRON

Variation and multi-time series prediction of total hardness in groundwater of the Guanzhong Plain (China) using grey Markov model.

Total hardness (TH) is an important index representing the water suitability for domestic purpose. TH is represented mainly by Ca2+ and Mg2+ which are essential elements for human bone development. Between 2000 and 2015, the TH values of groundwater in major cities of the Guanzhong Plain varied significantly. The study was carried out to investigate TH variation over 16 years and to examine how effective the grey Markov model was in predicting TH concentrations in time series datasets. The hydrochemical parameters determining TH concentration and their origins were investigated using statistical analysis and geochemical models. The grey Markov model, which is effective in short time series prediction, was used to forecast the multi-time series of TH. The findings demonstrated a prevalence of HCO3- and SO42- in the groundwater types combined with calcite precipitation, gypsum, and dolomite dissolution that increased the concentration of Ca2+, Mg2+, and HCO3-, influencing TH variation. The predicted TH values of the eight monitoring wells for the year 2016 were 1213.66, 124.30, 203.66, 103.01, 349.56, 251.23, 453.31, and 471.81 mg/L, respectively. Datasets with low TH variation were more accurately predicted than datasets with high TH variation. This was especially observed on sample B557 where TH concentration in 2010 was 400.33 mg/L and suddenly dropped to 90.1, 82.6, 85.1, 87.6, and 75.1 mg/L in 2011, 2012, 2013, 2014, and 2015, respectively. The study also shows that the Markov chain model can optimize the GM(1,1) model and improve the prediction accuracy significantly. All samples in Weinan City and one sample in Xi'an City showed a significant decrease in TH concentration. Except one sample in Xi'an City, TH concentrations tended to rise in the other cities (Baoji, Xianyang) of the Guanzhong Plain. This study verified the reliability of the grey Markov model in terms of forecasting time series datasets with high variability, and the results can be referential to similar studies in the world.

A unified multivariate statistical approach for the assessment of deep groundwater quality of rapidly growing city of Maharashtra Province, India, with potential health risk.

The main aim of this research is to assess the consequences of natural and anthropogenic processes on the groundwater quality of 65 deep aquifers of Nagpur city, Maharashtra Province, India, using a unified multivariate statistical approach. The dominant groundwater type recognized is Ca-HCO3 (recharge waters) in 43.1 and 38.5% of groundwater samples of pre- and post-monsoon seasons, followed by mixed water types. The seasonal distribution of physicochemical parameters shows increase in the concentration of EC, TDS, TH, Mg2+, SO42-, and NO3- signifying the high mineralization and anthropogenic loading from pre- and post-monsoon season respectively. The entropy-weight water quality index categorizes the 84.6% and 75.4% of total samples from pre- and post-monsoon seasons into moderate quality. The multiple linear regression and PCA analysis reveal the masking of rock weathering mechanism by anthropogenic activities. The % of PCA Variance varies from 79 to 83.7% from pre- to post-monsoon season. The high contributions of EC (0.76, 0.72), TDS (0.79, 0.73), TH (0.97, 0.962), Ca2+ (0.84, 0.78), Mg2+ (0.79, 0.83), Cl- (0.73, 0.75), and NO3- (0.78, 0.68) in PC1 components expose high salinity and hardness in urban groundwater that signifies the consequences of urbanization on the groundwater regime. About 55.4 and 70.8% of children population as compared to the adult female (53.8%, 69.2%) and male (32.3%, 46.1%) population in PRM and POM respectively were at high non-carcinogenic health threat of NO3--enriched groundwater. The study is beneficial for understanding the variation in groundwater composition due to unplanned urbanization and is very useful for protecting groundwater resources in urban areas.

Potential aquifer mapping for cost-effective groundwater reverse osmosis desalination in arid regions using integration of hydrochemistry, environmental isotopes and GIS techniques

In arid regions, water resources are scarce; therefore, sea and brackish groundwater desalination using reverse osmosis (RO) techniques is commonly used to provide freshwater for potable purposes. El-Moghra Oasis, a case study of an inland depression, represents an arid region in the Western Desert of Egypt. The oasis relies mainly on the brackish groundwater in El-Moghra Aquifer for salt-tolerant crop irrigation and feeding desalination plants. The RO brackish groundwater desalination conserves about 75% of the total cost compared to seawater as feed water. Accordingly, the main target of the present work is to allocate cost-effective sites for constructing desalination plants to solve freshwater shortages. The hydrogeochemical and isotopic techniques have been applied to understand the aquifer recharge mechanism and the main factors that deteriorate the groundwater quality. Additionally, an Analytical Hierarchy Process (AHP) relying on the geographic information systems (GIS) utilized to delineate the promising desalination sites. Four main criteria linked with the cost of RO groundwater desalination were investigated, including aquifer hydraulic parameters, hydrogeochemical characteristics, recharge indicators based on isotopic tracers, and other miscellaneous parameters related to the site accessibility and environmental issues. These four main criteria include fourteen sub-criteria; depth to water (DTW), aquifer saturated thickness (ST), transmissivity (T), total dissolved solids (TDS), iron (Fe), total groundwater hardness (TH), calcium sulfate (CaSO4), silica (SiO2), strontium (Sr), oxygen-18 (δ18O), global solar radiation (GSR), land slope (LS) and distance to roads (D). The final suitability map identifies the most favorable locations for constructing a desalination plant is in the northeast, which comprises 64.5% of the study area. The locations with low appropriateness are concentrated in the west and southwest and account for 35.5% of the area.

Spatial Analysis of Groundwater Hardness, Electrical Conductivity, pH, and Underlying Causes for Variations in Ratnapura District, Sri Lanka

Hardness in drinking water may not be harmful to human health, though it can cause a variety of problems at both the domestic and industrial levels, most notably its objectionable taste and scale deposition. Excessive hardness in groundwater of the Ratnapura district has been perceived, particularly in the district’s dry and intermediate zones. Despite the fact that many residents rely on groundwater for their daily needs, no previous groundwater hardness investigation has been conducted in the area. In this context, this research aims to analyze the spatial distribution of groundwater hardness as well as pH and electrical conductivity (EC), including possible underlying causes. Georeferencing and spatial interpolation techniques were used to visually analyze the spatial variation of these three parameters over the area. Results revealed contrasting differences in all three parameters in the wet zone of the district compared with the dry and intermediate zones as well as alarming ranges of parameter values that exceed the standard limits for drinking water. Further, the study reveals that both climate conditions and geological conditions play a vital role in deciding the constituents of groundwater.

Status of Groundwater Aquifers, Water Quality, Sources of Contamination, and Future Challenges in Bangladesh: A Comprehensive Review

The groundwater resource of Bangladesh is under increasing threat from population growth, over-water mining, quick urbanization, and pollution from industrial events with domestic and agricultural activities. The objective of this paper is to review over a hundred well-recognized national and international journals, conference proceedings, reports, and other related documents on the status of groundwater aquifers, water quality, sources of contamination, and future challenges in Bangladesh to develop sustainable groundwater resource management. The study observed that groundwater in several zones in the country has been contaminated with elevated levels of dissolved elements. Temporary hardness in countrywide groundwater was found in higher ranges for all purposes while except for bicarbonate, all anions did not cross the guideline value. Among the metal contaminants, arsenic found in the shallow aquifer at an alarming level throughout the country threatened public health, and millions of consumers are suffering from severe and chronic poisoning from arsenic riches water. Additionally, climate change and sea-level rise are likely with increasing salinity and various nutrient concentrations in the coastal aquifer systems of the country, and that water is not fit for domestic and agricultural uses.