Saline Water Intrusion Research Articles

Spatial and vertical distribution of uranium and associated hydro-geochemistry, chemometric statistics in groundwater of Mansa and Barnala districts, Punjab, India.

ABSTRACT Seawater intrusion (SWI) is the most important hydrological problem in the highly populated coastal regions. SWI in the coastal aquifers is caused by the intense withdrawal of groundwater and reversal of the natural hydraulic gradient. The study focuses on geophysical and geochemical analysis to identify areas contaminated by saline water intrusion. Resistivity survey and groundwater analysis were conducted in 33 locations in the study area to identify the extent of SWI. Geochemical analysis indicated that the groundwater quality was not suitable for drinking and irrigation purposes in 64% and 85% of the study area, respectively. The areas with low resistivity and high values of water quality parameters, such as electrical conductivity, chloride, and low values of Na/Cl, indicate SWI. Resistivity study was verified by geochemical studies, and the results indicated high salinity prevailed up to 13.7 km, moderate salinity up to 16.5 km, and freshwater was present beyond 16.5 km from the coast. The study found that geophysical methods offer a valuable alternative to laborious geochemical approaches for estimating aquifer parameters and detecting saline water intrusion. The study indicated the need for proper management of coastal aquifers to control SWI.

This study examines the impacts of climate change on fisheries and aquaculture in Bangladesh, one of the most climate-vulnerable countries in the world. The fisheries and aquaculture sectors contribute significantly to the national GDP and support the livelihoods of 12% of the total population. Using a Critical Literature Review (CLR) approach, peer-reviewed articles, government reports, and official datasets published between 2006 and 2025 were reviewed across databases such as Scopus, Web of Science, FAO, and the Bangladesh Department of Fisheries (DoF). The analysis identifies major climate drivers, including rising temperature, erratic rainfall, salinity intrusion, sea-level rise, floods, droughts, cyclones, and extreme events, and reviews their differentiated impacts on key components of the sector: inland capture fisheries, marine fisheries, and aquaculture systems. For inland capture fisheries, the review highlights habitat degradation, biodiversity loss, and disrupted fish migration and breeding cycles. In aquaculture, particularly in coastal systems, this study reviews the challenges posed by disease outbreaks, water quality deterioration, and disruptions in seed supply, affecting species such as carp, tilapia, pangasius, and shrimp. Coastal aquaculture is also particularly vulnerable to cyclones, tidal surges, and saline water intrusion, with documented economic losses from events such as Cyclones Yaas, Bulbul, Amphan, and Remal. The study synthesizes key findings related to climate-resilient aquaculture practices, monitoring frameworks, ecosystem-based approaches, and community-based adaptation strategies. It underscores the need for targeted interventions, especially in coastal areas facing increasing salinity levels and frequent storms. This study calls for collective action through policy interventions, research and development, and the promotion of climate-smart technologies to enhance resilience and sustain fisheries and aquaculture in the context of a rapidly changing climate.

Climate change can severely impact fishermen’s community due to the nature of their profession. This study investigates the impacts of climate change on sea-going fishers in Paikgachha Upazila, Khulna, Bangladesh. A total of 60 randomly selected fishers were interviewed using semi-structured questionnaires and focus group discussions to assess climate-induced changes in their livelihoods. Field data reveal that 100% of the respondents experienced reduced fishing duration due to frequent storms, erratic sea behaviour, and early seasonal changes. Around 40% of fishers have shifted to alternative professions, and approximately 40% of local residents have migrated over the past 20 years due to climate-related livelihood disruption. In 2022, 90% of fishers lost their prawn farms owing to saline water intrusion and elevated water temperatures. Climatic trend analysis using Bangladesh Meteorological Department data confirms an increasing pattern in mean temperature per year (+0.014℃) and rainfall (+7.22 mmyr-1) in coastal regions over the past three decades. The findings underscore the urgent need for targeted adaptation strategies, safety protocols, and livelihood diversification to support the resilience of this vulnerable population.

Agriculture in the coastal regions of West Bengal is increasingly threatened by extreme climatic events such as cyclones, erratic rainfall, sea-level rise, and saline water intrusion. These events jeopardise food security and rural livelihoods, particularly for small and marginal farmers with limited adaptive capacity. This study aims to identify and analyse the constraints faced by farmers in adapting to such climatic adversities in the coastal districts of South 24 Parganas and Purba Medinipur. An ex-post facto research design was adopted using a mixed-methods approach. Data were collected through structured interviews with 300 randomly selected farmers across four vulnerable blocks - Mathurapur II, Kultali from South 24 Parganas; and Ramnagar I and Ramnagar II from Purba Medinipur district. The perceived constraints were categorised into personal, technological, communicational, and institutional domains, and analysed using descriptive statistics and Garrett’s ranking technique. Findings revealed that high input costs, fragmented landholdings, and poor investment capacity were the most severe personal constraints. Technological constraints included over-dependence on monsoons, lack of technical guidance, and non-availability of salt-tolerant varieties. Inadequate extension services, limited access to information resources, and weak farmer membership in different organisations emerged as major communicational constraints. Institutionally, the absence of timely credit and inefficient compensation mechanisms was most prominent. Across both districts, farmers prioritised economic support measures - such as subsidies, input supply, and minimum support prices - as key adaptation needs. Notably, respondents of South 24 Parganas emphasised training and knowledge enhancement, whereas respondents of East Medinipur highlighted market access and soil health improvement. The study underscores the urgency of district-specific, multi-dimensional adaptation strategies that integrate financial support, policy reform, infrastructure investment, and capacity-building initiatives. Strengthening institutional and technical support systems is found to be critical for enhancing resilience in climate-vulnerable farming communities.

Climate change disproportionately affects coastal communities worldwide, increasing exposure to extreme temperature and saline water intrusion. Understanding these impacts is critical for public health planning and intervention. This study aims to examine the perceptions about the effects of climate change-induced phenomena, specifically extreme temperature and water salinity, on the overall human health of coastal communities residing in Ramgati, Lakshmipur, Bangladesh. The study adopted a quantitative research approach and utilized a cross-sectional survey design to gather data. The sample consisted of 391 participants (N = 391) residing in the coastal region of Ramgati. A structured questionnaire was employed to collect data. The gathered data were subjected to several bivariate analyses, including independent-sample t-tests, Pearson correlation analysis, and hierarchical regression analysis, using IBM SPSS version 24.0. Participants exposed to higher extreme temperature reported their perceptions of various health effects, such as heat stroke, dengue epidemic, migraine and headache. Additionally, participants experiencing elevated water salinity reported different health effects, including hair loss, high blood pressure, diarrhea, maternal health problems, child development, and hindered child mental health development. Linear regression analysis revealed that participants' age (β = 0.33, p < 0.001), gender (β = -0.16, p < 0.001), perceived risk of health diseases (β = 0.17, p < 0.001), high salinity in water (β = 0.15, p = 0.002), and high temperature (β = 0.25, p < 0.001) were significantly associated with the perception of health effects. This study highlights the importance of addressing key issues regarding the effects of extreme temperature and saline water on human health. Specifically, the study reports on access to clean drinking water, climate change adaptation strategies, health education and awareness, an integrated public health approach, and the needs of vulnerable populations, in order to mitigate the effects of climate change on human health living in the coastal areas.

This study explores the interplay of climate vulnerability and social capital in two rural communities: Brajaballavpur, a high-climate-prone village in the Indian Sundarbans characterized by high ecological fragility, recurrent cyclones, and saline water intrusion affecting water access, livelihoods, and infrastructure; and Jemua, a low-climate-prone village in the land-locked district of Paschim Bardhaman, West Bengal, India, with no extreme climate events. A total of 85 participants (44 in Brajaballavpur, 41 in Jemua) were selected through purposive sampling. Using a comparative qualitative research design grounded in ethnographic fieldwork, data were collected through household interviews, Participatory Rural Appraisals (PRAs), Focus Group Discussions (FGDs), and Key Informant Interviews (KIIs), and analyzed manually using inductive thematic analysis. Findings reveal that bonding and bridging social capital were more prominent in Brajaballavpur, where dense horizontal ties supported collective action during extreme weather events. Conversely, linking social capital was more visible in Jemua, where participants more frequently accessed formal institutions such as the Gram Panchayat, local NGOs, and government functionaries that facilitated grievance redressal and information access, but these networks were concentrated among more politically connected individuals. The study concludes that climate vulnerability shapes the type, strength, and strategic use of social capital in village communities. While bonding and bridging ties are crucial in high-risk contexts, linking capital plays a critical role in enabling long-term social structures in lower-risk settings. The study contributes to both academic literature and policy design by offering a relational and place-based understanding of climate vulnerability and social capital.

To ascertain the groundwater physicochemical quality and spatiotemporal variation, a systematic real-time hydro-geological field survey was conducted across 22 bore wells during both the Pre-Monsoon (PrM) and Post-Monsoon (PoM) seasons of 2022, in the Namkhana Development Block, South 24 Parganas, a significantly populated area of the Sundarban Biosphere Reserve (SBR). Hydrochemical analysis assessed its viability for drinking, domestic, and irrigation. The spatiotemporal fluctuation of cations and anions was portrayed by the concentration contour diagrams along with standard statistical approaches like correlation analyses and PCA to ascertain the interdependence between the major ions. Relevant plots and standard formulae were inculcated to evaluate the groundwater’s appropriateness for drinking and irrigation. Findings revealed a strong interdependence between EC, TDS, and Na+, whereas pH exhibited negligible influence. The dominant cation and anion sequence for both the PrM and PoM was (Na+ > Ca2+ > Mg2+ > K+) and (HCO3− > Cl− > SO42− > NO3−). Higher concentrations of Na+ and Cl− in coastal areas decreased inland, highlighting the effects of salt intrusion. Overall, the suitability of groundwater for agricultural, drinking, and domestic uses also varies adversely from its normal acceptable limits. Excessive and unregulated tapping of groundwater from the deeper aquifers for irrigation to meet the required yield seems to be the key reason for depleted water quality in the area. The findings underscore the importance of ion interactions and saline water intrusion in defining the groundwater situation in this region. The research output provides an updated hydrogeological status of the Block, useful for better water management plans relevant to public health engineering and irrigation.

Relative assessment of constrained multiple objective optimization techniques for optimal pumping strategy design to mitigate saline water intrusion in coastal groundwater systems

The tropical coastal regions are severely vulnerable to climate change and associated hazards, having a major impact on global hydrological cycle from the last three decades, with subsequent enhancement of hazards. Tidal inundations and the saline water intrusions are responsible for the disaster in coastal areas of West Bengal making people susceptible to livelihood hazards by affecting the agricultural land resources which transform into saline land resulting in joblessness and income reduction. Storm Surge and cyclonic high-speed wind break the weak river embankments, resulting in inundations. So, the aim of the study is to unfold the effect of inundation due to super cyclone Amphan and Yash on the livelihood of the rural people, in Ramnagar I &amp; II Blocks, of Purba Medinipur, West Bengal, India. NDVI during the years 2000, 2010 and 2022 reveal a decline in the values, ranging from -0.54 to +0.7 in 2000, -0.239 to +0.55 in 2010, and -0.16 to +0.51 in 2022, showing a gradual reduction in agricultural productivity during 2000 to 2022. Notably, the most pronounced changes in NDVI values occur between the coastline and 25 to 30 kilometers inland, an area where soil salinity has had a detrimental impact on the land. NDVI values have steadily decreased from 2000 to 2022, indicating reduced agricultural productivity. Agricultural land has decreased by 62.36%, while water proportions increased by 71.2% and rural settlements decreased by 37.64% due to water inundations during the period 2010 to 2022. Likewise, 6% of the respondents became jobless during post-disaster phase.

BackgroundClimate change and health issues pose a global threat, particularly in developing countries like Bangladesh. Within the socio-economic structure in coastal regions, women played a crucial role in contributing livelihood and living resources, while new climatic ecology creates chaotic relationships between environment and human health. The emerging adverse climatic ecology is directly and indirectly affecting them in the sphere of their both outdoor and indoor activism. This study explores the health impacts of climate change on the women of reproductive age (ages between 14 and 49 from the Bangladeshi perspective) living in coastal communities, i.e., Satkhira, Bangladesh.MethodsTo choose study locations, this study conducted a literature survey to find out the most vulnerable coastal region of Bangladesh. The study has selected the five most vulnerable unions of Shyamnagar upazila in Satkhira district. This study adopted a multi-method approach combining in-depth interviews and KIIs. Based on this methodological guide, this study interviewed 25 women and 5 married men, while their responses have further been supplemented and validated by KIIs with health workers and medical officers.ResultsFindings show that climate change posture to new climatic ecology facilitating adverse situations that lead to the intrusion of saline water within communities, lack of fresh and drinkable water, women exposure to waterborne diseases resulting from both salinity and scarcity of fresh usable water, skin disorders, gynaecological and reproductive illnesses, and vector-borne diseases. Women also bear an encountered burden in their struggle to acquire water and good health, including limited hygiene facilities and maternal care. This dilemma is even worsened during the summer season, which exposes women to heat waves, resulting in physical complications such as anaemia, pregnancy risks, heat stroke, dehydration, hypertension and psychological complications like anxiety, stress and depression.ConclusionBreaches in awareness and prevention practices were outlined from the study, as there is a need to realize integrated solutions to address the environmental and health challenges of the populations. Further, there is an absolute need to continue improving access to safe water, healthcare services, and education as a way to build resilience in affected communities.

ABSTRACT This study analyzed 44 groundwater samples – 30 from shallow (&amp;lt;200 m) and 14 from deep (&amp;gt;200 m) aquifers – to assess the drinking water quality in the Barguna district. Parameters such as temperature, electrical conductivity (EC), and pH were measured on-site and major ions (Na, Ca, Mg, K, HCO3, Cl, and SO4), As, Fe, and Mn were analyzed in the laboratory. The spatial distribution of ions shows higher levels of Ca, Fe, and HCO3 in shallow tubewells (STWs) in the north, and elevated levels of Cl, Na, and K in the south. In deep tubewells (DTWs), only HCO3 is higher compared with STWs. STWs are mainly NaCl-type, while DTWs are characterized by Ca-HCO3 and Na-HCO3 types. The high EC values and the presence of Cl and Na in STWs indicate brackish to saline water, likely due to ancient saline pockets or saline water intrusion. Meanwhile, the prevalence of HCO3 in DTWs, along with low Na and Cl, suggests relatively fresh groundwater not affected by saline intrusion. According to health risk guidelines, shallow groundwater is highly vulnerable to saline and As contamination, which poses significant health risks. Conversely, deep groundwater is considered safe for drinking as it appears free from As contamination.

Saline water is measured by its salinity, the amount or concentration of dissolved salts. Daily, a tidal phenomenon occurs in the Parit Botak channel, regardless of whether it is low or high. There is no tidal gate that separates the Parit Botak channel from seawater. Hence, the primary objectives of this study are identifying saline water characteristics and investigating the saline water intrusion patterns during high tide along the Parit Botak channel. In this study, in-situ testing methodology was employed using a multifunctional water quality tester. Three stations were selected to conduct in-situ tests to identify the characteristics of saline water flow in the open channel. The investigation of saline water intrusion was carried out with daily data collection during high tide from November 1st to December 31st, 2023. Weather conditions and moon phases were not considered in this case study. Thus, the investigation along the Parit Botak channel revealed that the water characteristics classify it as brackish to saline, with moderate salinity levels. In addition, the saltwater intrusion was stretched to a distance of 18.03 km, accompanied by a tidal height of 2.96 m. The tide heights impacted the degree and variations of saltwater infiltration, although this relationship was not consistently linear. The irregularity of the fluctuation patterns was caused by severe precipitation or the moon phase.

Remote sensing assessment of the weed adaptability to soil salinization induced by extreme droughts on coastal agriculture

The people of the coastal parts of Bangladesh are insecure for safe drinking water. Present study is an attempt to delineate the water quality in the coastal parts of Mirsharai, Sonagazi and Companiganj areas. Various parameters of water quality such as free hydrogen (pH), electrical conductivity (EC), total dissolved solids (TDS), oxidation reduction potential (ORP), salinity, turbidity, dissolved oxygen (DO), biological oxygen demand (BOD), chemical oxygen demand (COD), acidity, alkalinity, total hardness and nitrate, phosphate, sulphate, chloride, iron, manganese, cobalt, nickel, arsenic and chromium were determined through field work, available data and laboratory analysis. The results indicate that the arsenic concentration and electrical conductivity in shallow aquifers exceed WHO and Bangladesh standards limit. Additionally, chloride, total hardness, alkalinity, and lead exceed the WHO and Bangladesh standards in both shallow and deep aquifers. In many cases, the turbidity of surface water both inside and outside the coastal embankments also exceeds these limits. The lead, chloride and manganese contents, DO and BOD in the Feni River also exceed the BSTI limits. The analysis reveals that the deep aquifers are free from arsenic, while the shallow aquifers are significantly contaminated. Although, the deep aquifers need precaution for salinity, alkalinity, total hardness and lead contents. Correlation matrix analysis confirms that EC and TDS serve as reliable indicators of salinity levels in both shallow and deep aquifers. Principal Component Analysis (PCA) further supports this, showing that EC, TDS, and salinity are influenced by the saline water intrusion in these aquifers. Additionally, pollutants in both shallow and deep aquifers are positively associated with EC, TDS and salinity. Keywords: Drinking water insecurity, water quality analysis, coastal areas, Bangladesh.

Influence of saline water and heavy rain on the fate of chlorinated ethenes in groundwater characterized by compound-specific isotope and microbial data.

Excessive groundwater abstraction in coastal areas exacerbates saltwater intrusion (SWI), a widespread global issue. Characterization of mechanisms delivering saltwater to wells can assist in developing suitable SWI mitigation strategies for reducing the risk of groundwater degradation. This paper presents findings from hydrogeological monitoring, time-lapse electrical resistivity tomography (ERT) and self-potential (SP) measurements to investigate SWI under natural and artificially perturbed conditions in a quasi-homogeneous pristine coastal sand aquifer, affected by large tidal ranges (>2m). Time-lapse ERT surveys conducted under undisturbed conditions identified an upper saline recirculation cell (IRC) beneath the intertidal zone, arising due to seawater infiltrating into an underlying ∼20m thick sand sequence containing fresher groundwater, with resistivity variations noted between spring and neap tides. Measurements taken during a 69-h constant-rate pumping test, discharging at 10.2L/s, revealed that pumping drew saline water from the IRC towards abstraction wells. This resulted in saltwater contributions to discharge increasing from 1.4 to 4.1%, consistent with the decrease in resistivity detected in ERT profiles between 3m and 7m below surface. Over the same period, SP signals fell by between 20 and 30mV with greater declines occurring at locations nearer to the high-water mark. Monitoring data suggest that these changes in SP are primarily due to saline water intrusion from the IRC, rather than pressure changes resulting from pumping. Research findings provide further evidence that SP monitoring could act as a key geophysical early warning parameter for SWI, while ERT data further highlight the potential for monitoring SWI in shallow coastal aquifers. This study also demonstrates that optimal groundwater abstraction strategies in tidal-influenced coastal aquifers can be achieved by targeting deeper zones.

Paddy soils undergo wet-dry cycles that greatly influence the behaviour and availability of nutrients, but also of potentially toxic elements (PTEs). This study assessed the quality of paddy soils (actively cultivated and abandoned) and rice (white, brown, and wild) produced in the Baixo Vouga Lagunar (BVL) region, central-north Portugal. Surface soils were analysed for physicochemical parameters and chemical compositions, alongside sequential selective chemical extraction to evaluate metal(loid) availability. Chemical analyses were also performed on interstitial- and irrigation waters, and rice grains. The BVL soils are very strongly to moderately acidic (pH = 4.4–5.8), with organic matter contents reaching up to 34%, and exhibit a wide range of electrical conductivity values. Abandoned rice fields generally show higher values of these parameters and evidence of saline water intrusion. Several sites showed As, Cu, Pb, and U concentrations exceeding Portuguese thresholds for agricultural soils. While Cu levels were similar in both cultivated and abandoned fields, the latter had higher contents of As, Pb, and U. A geogenic origin is envisaged for these metal(loid)s, though anthropogenic contributions cannot be excluded. Sequential selective chemical extraction showed that Pb and U are strongly associated with available fractions, whereas amorphous Fe-oxyhydroxides primarily support As and Cu. Nevertheless, porewaters and irrigation waters showed low concentrations of these PTEs, suggesting minimal mobilisation to water. Furthermore, translocation to rice grains was low, with concentrations well below European Commission limits, indicating that elevated PTEs in soils do not necessarily lead to toxic levels in rice, providing reassurance regarding food safety.

This study investigates the presence and spatial extent of saline water and seawater intrusion in the Subiya Peninsula, Kuwait, a region designated for the establishment of the new Silk City. We collected transient electromagnetic (TEM) data at 63 stations using a coincident loop setup on a regional, as well as local, scale. The data were analyzed through conventional 1D inversion techniques, including Occam and Levenberg–Marquardt methods, to create detailed resistivity models of the subsurface. Our findings indicate significant variations in groundwater salinity, with increased salinity towards the coast and partly decreasing resistivity with depth, suggesting a transition from brackish to saline water. In the northern region, close to the Abdali farms and Al-Raudhatain freshwater fields, groundwater remains fresher at greater depths, while in the south, saline conditions are encountered, occurring at shallower depths. Local scale analysis reveals potential saltwater intrusion pathways and highlighted geological features such as faults. A thorough understanding of the hydrogeological conditions is crucial, as saltwater injection for oil recovery is common in Kuwait, and may correlate with present-day seismic activity. These insights are critical for the sustainable planning and development of Silk City, emphasizing the necessity for further geophysical studies and borehole data to ensure construction safety and sustainable water supply management. This research provides a foundational understanding of the hydrogeological conditions essential for the successful implementation of the Silk City project and for groundwater management in northern Kuwait.

In coastal saline–alkali regions, the intrusion of saline water exacerbates the nutrient depletion in the plow layer, posing a significant challenge to agricultural productivity. Given the limited understanding of soil fertility in these areas and the inconsistent results among different assessment methods, this study aims to develop a more accurate and reliable soil fertility evaluation system. To achieve this objective, 108 topsoil samples were systematically collected from saline–alkali lands in Jiangsu Province. Several key soil fertility indicators, including soil pH, total salinity (TS), soil organic matter (SOM), total nitrogen (TN), total phosphorus (TP), total potassium (TK), alkaline-hydrolyzable nitrogen (AN), available phosphorus (AP), and available potassium (AK), were comprehensively evaluated. Four advanced methods, namely principal component analysis indexing–linear scoring (SQIPCAL), principal component analysis indexing–nonlinear scoring (SQIPCANL), modified Nemerow–linear scoring (SQINemeroL), and modified Nemerow indexing–nonlinear scoring (SQINemeroNL), were employed to conduct a multi-dimensional examination of soil fertility. Additionally, principal component analysis (PCA) was utilized to establish a minimum data set (MDS), which was then compared with the total data set (TDS) for a more precise assessment of soil fertility. Linear scoring methods (SQIPCAL and SQINemeroL) had higher semi-variogram R2 values compared to nonlinear methods. Moreover, under the SQIPCAL and SQINemeroL evaluation methods, a strong correlation was observed between the TDS and MDS, with R2 values reaching 0.63 and 0.65, respectively. Based on these findings, the SQINemeroL method, integrated with MDS, is recommended as an effective approach for soil fertility assessments in coastal saline–alkali regions in Jiangsu Province. This research not only enriches the theoretical understanding of soil fertility in such regions but also provides practical insights for sustainable agricultural management.