Sustainable Management Of Groundwater Resources Research Articles

Spatial prioritization of groundwater resources in mountain region of Nepal: a GIS and AHP integrated framework

ABSTRACT Climate change and anthropogenic activities pose major challenges to water resource management in water-scarce mountain regions. Managing and monitoring groundwater effectively is crucial in mitigating these challenges. Understanding groundwater resources and their distribution is necessary for effective management. The present study covers Doramba rural municipality of Nepal. It employed the analytic hierarchy process (AHP) as a multi-criteria decision-making (MCDM) tool integrated with remote sensing (RS) data and geospatial techniques to identify groundwater potential zones (GPZs). The parameters for analysis include drainage density, slope, rainfall, lineament density, land use/land cover (LULC), soil, geology, curvature, roughness, topographic wetness index, and topographic position index. These 11 thematic layers of the study area were prioritized using Satty's AHP method for the delineation of GPZs. The results classified the study area into very high, high, moderate, low, and very low groundwater potential classes, covering 26.71, 27.98, 46.61, 34.71, and 4.89 km2, respectively. The delineated map accuracy was confirmed with a 70.7% prediction rate based on the spatial distribution of 56 springs in the study area. The study's results can be applied to the sustainable management of groundwater resources in the study region and other areas with similar hydrogeological conditions.

Quantifying groundwater depletion in Arabian Peninsula transboundary aquifer systems: Understanding natural and anthropogenic drivers

Groundwater is the primary source of freshwater for domestic, agricultural, and industrial usage in the Arabian Peninsula countries. It is increasingly becoming a limited resource due to human activities leading to excessive depletion and contamination. Thus, sustainable management of groundwater resources in this region is critical. The groundwater in the Arabian Peninsula countries is primarily found in transboundary systems such as the Wajid, Umm Er Radhuma, and Wasia Aquifers shared between Saudi Arabia, Iraq, Syria, Yemen, and Oman. These systems have no groundwater-sharing agreements, which leads to a lack of data sharing, unsustainable and uncoordinated development, rapid water depletion, water quality deterioration, and land subsidence. This study examines the Wajid, Umm Er Radhuma, and Wasia aquifer systems from April 2002 to May 2021 by analyzing monthly gravity field solutions from GRACE and GRACE-FO satellite data, other remote sensing observations, information from the Global Land Data Assimilation System (GLDAS), as well as field data to determine how regional water resources are changing over time and to identify the factors that influence these resources. The sharp decline in Total Water Storage Anomalies (TWSA) and the Groundwater Storage Anomalies (GWSA) across all three systems is caused by a combination of climatic and human factors. The observed decline in Total Water Storage can be partly attributed to a decrease in regional rainfall, whereas the depletion of Groundwater Storage has a strong correlation with the rise in groundwater extraction for irrigation purposes in the 2010s. The recent rise is groundwater depletion in specific areas of central Saudi Arabia may be attributed to agricultural irrigation and rapid urban development. The results are insightful for monitoring water storage in management plans and decision-making processes to preserve and efficiently use groundwater resources.

Indicator assessment of groundwater resource sustainability: Using the framework of socio-ecological systems in Hamedan - Bahar Plain, Iran

Study areaIran. Study focusHamedan-Bahar plain is one of the important plains in the west of Iran, which is facing a shortage of water resources and excessive extraction of groundwater resources. The purpose of this article is to identify and evaluate the status of sustainability governance indicators using the knowledge of local experts, which can be an effective step towards the sustainable management of groundwater resources. In this paper, we apply Ostrom’s Social-Ecological Systems Framework (SESF) as a diagnostic tool with 52 indicators to assess the sustainability of groundwater resources. New hydrological insights for the regionBased on key informant interviews with local experts and stakeholders, we use the TOPSIS technique and the Shannon Entropy methodologies to weigh and rank indicators influencing sustainability. Findings revealed that the indicators within the category Resource Systems (RS) and Resource Units (RU) with values of 0.74, and 0.70, are the most stable contributing factors to local sustainability, respectively. In contrast, the Governance System (GS), Actor (A), and Interaction (I) first-tier variables were evaluated as less stable, along with Outcomes (O). This suggests that social factors and diverse outcomes may need further attention in the region to ensure management and policy development that can better enable sustainable outcomes. This analysis also demonstrates the usefulness of a comprehensive science-based framework for organizing, analyzing, and presenting a wide range of complex information to inform policymakers and planners.

Investigating seawater intrusion and salinization using the integration of hydrochemical and geoelectrical techniques

Seawater intrusion poses a significant environmental threat to water resources, agriculture, and ecosystems. We investigate the extent of seawater intrusion and salinization in the eastern coastal aquifers of Saudi Arabia. Hydrochemical measurements and electrical resistivity tomography (ERT) techniques are used to assess groundwater quality and the subsurface extension of seawater intrusion. Two resistivity profiles, 475 m long each, are analyzed to gain insights into the subsurface geology and seawater intrusion. The inversion of the recorded resistivity data reveal four distinct subsurface layers. The uppermost layer consists of surficial deposits, followed by a sandy seawater intrusion layer, beneath which lies a marl layer, and at the bottom, a dolomitic limestone layer representing the brackish-water aquifer. The ERT results are integrated with hydrochemical and hydrogeologic results from 12 wells to overcome the limitations of the ERT. The findings of this study would facilitate the development of efficient mitigation strategies and sustainable management of the groundwater resources in the study area or similar coastal regions affected by seawater intrusion. Understanding and delineating the boundary between saline and fresh water is crucial for safeguarding water resources for agricultural purposes, preserving ecosystem health, and ensuring the long-term sustainability of water supplies in coastal areas.

Hydrochemical and Formation Mechanism Studies of Groundwater in Quaternary Aquifer in a Northern Plain of China: An Example of Beijing Plain

Beijing Plain is a very active part of Beijing city regarding the socio-economic and human activities of the region. Over the past four decades, Beijing’s economic development and the continuous drought for nearly 10 years in the 2000s have negatively impacted the groundwater quantity and quality. Therefore, it is necessary to investigate the present situation of groundwater chemistry in this region to develop a comprehensive database and orientation for future research on groundwater quality evaluation. Mathematical statistics, Piper’s trilinear diagram, Gibbs plots, the ion ratio method and PHREEQC software 3.7.3 were used to analyze the groundwater hydrogeochemical characteristics and formation mechanisms of the quaternary aquifers of the Beijing Plain area. Hydrogeochemical results indicated that the groundwater is slightly alkaline, with pH values ranging from 6.76 to 8.65 and an average value of 7.92. The order of major cations in groundwater was Ca2+ > Na+ > Mg2+ > K+ with average values of 66.54 mg/L, 50.58 mg/L, 23.78 mg/L, and 1.81 mg/L, respectively, while the order of major anions was HCO3− > SO42− > Cl− with average values of 284.89 mg/L, 52.1 mg/L and 35.5 mg/L, respectively. The groundwater chemical types are Mg-Ca-Cl-HCO3, Na-Ca-HCO3, Mg-Ca-HCO3 and Mg-Na-HCO3. Research on the main influencing factors and PHREEQC hydrogeochemical inverse simulations results along the four pathways selected confirmed that rock weathering with sulfate, silicate and carbonate rock mineral dissolution and Na+, Mg2+ and Ca2+ ion reaction exchange influenced groundwater hydrogeochemical characteristics of the quaternary aquifers of the Beijing Plain area. Understanding the formation mechanisms of hydrogeochemistry in quaternary plains provides guidance for future studies and, through suggestions and case studies, facilitates decision-making by policy-makers on the sustainable management of groundwater resources.

Exploring the InSAR signature associated with river-sourced recharge in California’s San Joaquin Valley

Recharge is a critical component for understanding aquifer systems and the sustainable management of groundwater resources, yet this process is challenging to measure at policy-relevant spatiotemporal scales. Building upon previous research, we tested the hypothesis that InSAR can be used to observe river-sourced recharge if the underlying recharge pathways are associated with sufficient clay content. Our analysis leveraged the decomposition of InSAR time series with interpretations of 3D resistivity models derived from airborne electromagnetic (AEM) surveys. We focused our analysis on two study sites where high density AEM data were available and river-sourced recharge is determined to have occurred during wet years: (1) near Fresno, California and (2) near Visalia, California. Sediment type and hydrogeological structure from AEM supported our hypothesis with the InSAR signature attributed to river-sourced recharge occurring only in the study site with semi-confined to confined conditions and relatively high fraction of interbedded clay within recharge pathways. The timing to peak amplitude, the key feature we wanted to isolate in the InSAR data, near Visalia was interpreted as a pressure pulse front associated with river-sourced recharge propagating into the San Joaquin Valley. This study further validated the potential of InSAR, coupled with AEM data, to map and monitor river-sourced recharge in aquifer systems. As InSAR data become more accessible, this approach holds promise for broader applications in groundwater science and management worldwide.

Combination of remote sensing, GIS, AHP techniques and geophysical data to delineate groundwater potential zones in the Shiriya River Basin, South India

Shiriya River Basin (SRB) of Kasaragod district, Kerala, is one of the minor river basins that faces acute water shortage soon after the rainy season. Increasing the aquifer productivity of the SRB is the need of the hour. The present study is performed to determine the groundwater potential zones (GWPZ) of the SRB through Weighted Overlay Analysis. Different thematic layers (Geomorphology, Geology, Lineament density, Slope, Drainage density, LULC, and Soil) were prepared. Based on Saaty's scale, the rank and weightage assigned to each thematic layer and their respective features were standardized through the AHP techniques. Subsequently, GIS-based Weighted Overlay Analysis generated the ultimate GWPZ map, dividing SRB into 3 potential zones (poor, moderate, and good). To validate the GWPZ and understand the geoelectric characteristics of the SRB, 50 Schlumberger VES were performed and analyzed. Depth to water level data is also used to validate the GWPZ. The VES data indicated three distinct geoelectric layers, the topsoil, laterite, and weathered/fractured basement, overlying the resistive basement. In the SRB second layer (laterite) and, in some regions, the third layer (fractured charnockite) functions as an aquifer. The presence of groundwater potential region is indicated by resistivity values ranging from 50 to 200 ohm-m. The combination of surface and subsurface indicators of GWPZ will be much more reliable in locating the site for sustainable groundwater exploration and management of SRB groundwater resources.

MAPPING THE GROUNDWATER POTENTIAL IN SUB-SAHARAN AFRICA: THE CASE OF THE COMMUNE OF LOUMBILA, BURKINA FASO

The objective of this study is to identify and map potential groundwater resource areas in the rural commune of Loumbila in order to assess the potential water accessibility in the area. A spatial data analysis was applied to identify potential groundwater resource areas for drilling. To this end, geomatics tools (Geographic Information Systems and Remote Sensing) and a multi-criteria analysis using the Analysis Hierarchy Process (AHP) technique were deployed. A total of eight (decision) factors with a strong influence on the groundwater storage potential (i.e., soil types, fracture network density, land use, slope, hydrogeology, alterity thickness and drainage density, precipitation) were selected and mapped. An appropriate weight has been assigned to each factor, which were further normalized using the Analytical Hierarchy Process (AHP). Based on the analysis, the rural commune of Loumbila was qualitatively classified into five groundwater potential zones: very low, low, medium, high and very high groundwater potential. The results obtained show that 9.80% (14.75 km2), 22.02% (33.16 km2), 30.68% (46.19 km2), 18.47% (27.81 km2) and 19.03% (28.65 km2) of the rural municipality of Loumbila have very high, high, medium, low and very low groundwater potential, respectively. The groundwater potential mapping aims to identify the areas with the highest potential for the sustainable management of groundwater resources, enabling informed decisions to be taken for its management and conservation.

Mapping and projecting spatiotemporal trends in groundwater levels and flow direction in Pakistan's water-scarce aquifer system

Groundwater is the most vital and reliable source of fresh water globally. This study examined the variability in Depth to Water table (DTW) below ground level in agriculture-dominated Bari interfluve, Pakistan. Observing water levels empowers access and management of water resources ensuring long-term availability. Changes in the DTW were observed by preparing spatiotemporal maps using piezometric data for both pre-monsoon and post-monsoon seasons by five-year difference intervals from 2005 to 2020. Piezometric observations offer more precise real-time monitoring of subsurface water levels. The trend of the groundwater table was analyzed by non-parametric methods i.e., Mann-Kendall (MK) and Sen's slope estimator in all observation wells of districts at a significance level of 5 percent for sustainable groundwater resource management. The resulting trend of fluctuating water table showed a progressive decline in water level in all districts except a minor increase was also noticed. The seasonal fluctuation (between pre-monsoon and post-monsoon seasons) showed that the average DTW was found to be high in 46% of the total tehsils in the post-monsoon season while in 42% it was low and 12% depicted no change compared to pre-monsoon season. Piezometric observation points of DTW exhibiting a trend at a 5 percent significance level were used to project future water table depths that indicated a further alarming depleting trend for both the pre-monsoon and post-monsoon seasons in lower districts of Bari interfluve. The groundwater pattern calls for precautionary measures to see a reversal in trend or even maintain the groundwater levels for future needs.

Review: Application of hydrogeological models coupled with agent-based models to address sustainable groundwater management in Latin America

Agent-based models (ABMs) have long been applied in economics and social science research. The combination or coupling of these models with those of natural systems is a more recent application, and their use in conjunction with groundwater flow and transport models can be considered an innovative way to take advantage of their potential. In the Latin American region, sustainable management of groundwater resources can still be considered understudied. Among other characteristics, the existence of large transboundary aquifers in the region adds a further complication for addressing the sustainability of groundwater resource use. In this type of system, the impacts of joint regulations for utilization by different countries, the diversity of socioeconomic drivers and the conservation interests of each group of users might be consistently represented and explored through flow models coupled with ABMs. This review of the scientific literature aims to compile up-to-date information regarding the application of hydrogeological models coupled with agent-based models, focusing on their contributions to the sustainable management of groundwater resources and analyzing their potential for the Latin American region.

Priorities and potential challenges of sustainable management of ultra-deep groundwater resources in Iran

The water crisis in Iran, and the large share of water allocated to the agricultural sector from groundwater resources has led to access to ultra-deep groundwater (UDGW) resources. Exploration projects have confirmed the presence of UDGW sources of fault origin in Iran. Deciding on the sustainable extraction of UDGW resources is very challenging. In order to better understand the scope and nature of the UDGW literature, our research combines a methodological framework of systematic literature review with an approach to synthesize manifest and latent content. Additionally, we describe expert predictors for and against inductive content analysis, which extracts necessary concepts, priorities, organization, and coding from the data. MFA tool has analyzed sustainability indices, compositions, correlations perceptual behavior of sustainability dimensions of groups in the variables predicting the exploitation of UDGW. In the proposed model, the synthetic index has determined weighting commensurate with the variability of data, to balance the effect of groups of variables. The most important dimensions of sustainability are Proxy/flexibility measures (69.4), Fund (63.3), Safety (63.2) and Extent and possibility of access and exploitation (63.06) of UDGW resources from engineering, social and environmental groups, respectively. However, the performance of Evaluation of quantity and quality of UDGW resources (39.8) and Fairness (42.3) groups were the lowest due to the environmental and social sustainability, respectively. In fact, a fair and sustainable expedient strategy and a restructuring of hydro-social networks that clearly acknowledge the political aspect of resource management and its intricacies are required. The ministry and the UDGW decision-makers themselves must solve these shortcomings.

Assessing groundwater quality in semi-arid conditions: a geographic information systems-integrated approach using water quality index

Meeting freshwater demands in water-scarce regions is imperative, given challenges like hydric stress, urbanization, aridity, and population growth. This study focuses on the Tebessa aquifer system, a critical water source facing escalating demands. A primary objective is to identify actionable management strategies to improve groundwater quality dynamics in semi-arid regions. The methodology involves a comprehensive assessment of groundwater health using the Water Quality Index (WQI) approach. This method integrates diverse parameters influenced by intensive agricultural and industrial activities. Additionally, spatial relationship analysis, facilitated by Geographic Information System (GIS) technology, is employed to gain insights into complex hydrogeological processes. The multi-parameter strategy implemented results in water quality maps that highlight various ions, revealing spatial disparities and assigning quality priority classes from 'Good' to 'Poor' across the groundwater. The research, conducted in the semi-arid Tebessa-Morsott Plain, encompasses field and laboratory investigations to delineate hydrochemical traits, including alkalinity, salinity, and heightened ion concentrations. The results of the study contribute to scientific understanding by uncovering interrelationships and spatial intricacies, offering valuable insights for water resource governance. The effectiveness of the methodology, incorporating WQI and GIS, is demonstrated in the comprehensive evaluation of groundwater quality. Ultimately, this research provides a foundation for informed decision-making and sustainable management of groundwater resources in semi-arid regions.

Site-specific condition evaluation for managed aquifer recharge (MAR) site selection in granitic aquifers, Ghana

ABSTRACT Water has prominence over all the usable natural resources to humankind due to its very significance to human life. Approximately, 70% of Ghana's populace relies on groundwater exploitation for freshwater consumption. Managed aquifer recharge is capable of sustaining water resources for all livelihood activities. Underperformance of MAR systems is often due to site-specific hydrogeological conditions turning out to be less favorable than anticipated. This study evaluates the site-specific conditions for MAR sites identification in granitic aquifers, integrating in situ hydrogeological factors and GIS-MCDA. One hundred and twenty-one datasets from different boreholes comprising hydro geophysics, borehole drilling and pump test reports were used. The constraint mapping results indicate 92% suitable for MAR application within the study area, implying available enormous bare lands for flooding recharge technique. The suitability analysis discloses that 48 and 51% of the studied area fall within very high and high suitable zones, respectively, showing convincing and great potential to support infiltration ponds for MAR technology application. The valuable information provided through this study can serve as a guide for MAR implementation and for sustainable groundwater resources management within the Upper East region of Ghana.

Analysis on the spatiotemporal evolutions of groundwater hydrochemistry and water quality caused by over-extraction and seawater intrusion in eastern coastal China

The over-extraction of groundwater has resulted in seawater intrusion and the southward migration of the saltwater interface, gradually deteriorating the groundwater quality in the Weibei Plain. In this research, groundwater samples were gathered from 46 monitoring wells for shallow groundwater during the years 2006, 2011, 2016, and 2021. The hydrochemical features of regional groundwater and the factors influencing the issue were subjected to statistical analysis. Additionally, the assessment of spatiotemporal variations in groundwater quality was conducted using the customized entropy-weighted water quality index (EWQI) method. The relationship between groundwater over-extraction and the southward intrusion of the saltwater interface was compared and analyzed. The results of this paper revealed that the Weibei Plain has been in a state of long-term over-extraction of groundwater from 2000 to 2021, with an average annual over-extraction of 118.49 million m3. The groundwater depression cone areas in the northern part of the study area increased from 3,247.37 to 4,581.34 km2 from 2006 to 2021, with the center of the cone experiencing a drop in groundwater level from −22 to −85 m. The saltwater interface shifted southward by 711.71 km2 from 2006 to 2021. In groundwater, the high concentrations of TH, TDS, and Cl− were primarily related to the seawater intrusion, while higher concentrations of NO3− were mainly determined by frequent agricultural production, industrial wastewater, and domestic sewage discharges. The groundwater hydrochemical types in the study area transitioned from predominantly HCO3·Ca-Mg type in 2006 to HCO3-Na type and SO4·Cl-Ca·Mg type in 2021 due to seawater intrusion. The results of PCA and HCA show the effects of seawater intrusion, human activities, and rock weathering on groundwater hydrochemistry. The evaluation results based on the EWQI revealed that the average value of the samples in 2021 was 101.36, which belonged to Class IV water quality standards, representing the poorest water quality among the 4 years. The southward migration of the saltwater interface led to the deterioration of groundwater quality in the groundwater depression cone areas, which gradually worsened from 2006 to 2021. The maximum increase in EWQI value was 174.68 during the period, shifting from Class III water quality to Class V water quality. Groundwater quality remained relatively better in the western and southern regions which were less affected or unaffected by seawater intrusion. The results of the study can provide a certain reference value for the sustainable management of groundwater resources and the management of groundwater pollution and seawater intrusion in the Weifang City area in the future.

Delineation of Groundwater Potential Zones for Sustainable Development and Planning using AHP and GIS Techniques in the Coal Mining Province of Mahan River Catchment Area

The present research aims to address the drinking water crisis in the Mahan River catchment area resulting from the disruption of groundwater availability due to extensive coal mining. The study uses GIS-based Multi-Criteria Decision Analysis (MCDA) to map the groundwater potential of the area by analysing several factors that affect groundwater availability, including rainfall, water depth, geomorphology, geology, soil, land-cover/land-use, and topographic characteristics derived from DEM. The groundwater potential map created using the MCDA technique classified the area into low, moderate, and high groundwater potential zones. The map was validated and verified using water table depth and electrical conductivity values available in the region, indicating that it can be used to identify groundwater recharging sites. The study’s results show that about 30% of the area has high groundwater potential, and more than 45% of the area has moderate groundwater potential. The information derived from the study can be used for sustainable management and proper planning of groundwater resources in the Mahan River catchment area. Overall, the study presents a useful approach to address the groundwater depletion problem resulting from coal mining activities in the Mahan River catchment area.

CALDERA: a scientific drilling concept to unravel Connections Among Life, geo-Dynamics and Eruptions in a Rifting Arc caldera, Okataina Volcanic Centre, Aotearoa New Zealand

Abstract. Silicic caldera volcanoes present major volcanic and seismic hazards but also host dynamic hydrothermal and groundwater systems and a rich but largely unexplored subsurface biosphere. Many of these volcanoes are hosted in rift settings. The intricate connections and feedbacks among magmatism, rifting, hydrothermal processes, and the biosphere in these complex systems remain poorly understood, necessitating subsurface joint observations that are only enabled by scientific drilling. The CALDERA (Connections Among Life, geo-Dynamics and Eruptions in a Rifting Arc caldera) project workshop funded by the International Continental Scientific Drilling Program (ICDP) gathered multi-disciplinary international experts in January 2023 to advance planning of a scientific drilling project within one of these dynamic, rift-hosted calderas, the Okataina Volcanic Centre (OVC), Aotearoa New Zealand. The OVC's high eruption rate, frequent unrest events and earthquake swarms, location in a densely faulted rapidly extending rift, abundant groundwater–geothermal fluid circulations, and diverse surface hot spring microbiota make it an ideal location for exploring a connected geo-hydro-biosphere via scientific drilling and developing a test bed for novel volcano monitoring approaches. Drilling configurations with at least two boreholes (∼ 200 and ∼ 1000–1500 m deep) were favoured to achieve the multi-disciplinary objectives of the CALDERA project. Decadal monitoring including biosphere activity and composition has the potential to evaluate the response of the hydro-bio system to volcano-tectonic activity. In addition to the OVC caldera-scale datasets already available, site surveys will be conducted to select the best drilling locations. The CALDERA project at the OVC would provide, for the first time, an understanding of volcanic–tectonic–hydrological–biological connections in a caldera–rift system and a baseline for global comparisons with other volcanoes, rifts, and hydrothermal systems. CALDERA would serve as an unprecedented model system to understand how and how quickly the subsurface biosphere responds to geologic activities. Discoveries will improve assessment of volcanic and seismic hazards, guide the sustainable management and/or conservation of groundwater and geothermal resources and microbial ecosystems, and provide a forum for interweaving mātauranga Māori and Western knowledge systems.

Groundwater Modelling of Jamwa Ramgarh using Visual MODFlow Flex

A steady state finite difference model, MODFLOW, is developed to quantify groundwater in Jamwa Ramgarh, Jaipur (Dt) Rajasthan, using Groundwater data from 06 observation wells. ArcGIS was used to generate various shapefiles required as input files in Visual MODFlow Flex. The findings indicate that the calculated contours of groundwater levels closely correspond to the observed contours. The sustainable utilization and management of groundwater resources pose significant challenges for many countries worldwide. In recent years, groundwater modelling has emerged as an effective approach to tackle these challenges. Various modelling software tools are available to simulate groundwater flow, with MODFLOW being widely used to investigate the interactions between surface water and groundwater and to develop models for specific study areas. MODFLOW, a renowned groundwater modelling software, enables researchers and water resource professionals to understand and analyze the complex dynamics of groundwater systems. By utilizing MODFLOW, it becomes possible to assess the interactions between surface water and groundwater, evaluate the impacts of pumping or recharge activities, and make informed decisions regarding the sustainable management of groundwater resources. The utilization of MODFLOW and similar modelling software plays a crucial role in advancing our understanding of groundwater systems and supporting effective groundwater resource management practices.

Water Governance in Tanzania – A Synthesis of Legal and Institutional Frameworks for Groundwater Management in the Upper Great Ruaha River Catchment

The importance of groundwater resources in buffering the effects of climate change on water scarcity and security is highly acknowledged worldwide. However, groundwater development and use can only be sustainable with a more robust policy and institutional arrangements related to water governance. The purpose of this study was to analyse the legal framework of water resource development and management in order to contribute in identifying policy constraints to sustainable groundwater resource development and management in Tanzania. The paper used information from literature reviews and data collected through qualitative methods using a case study of Usangu Plains in the Upper Great Ruaha River Catchment in Tanzania. The findings reveal that water governance institutional frameworks are well structured to provide guidelines on how water as a basic human resource can be utilised and properly managed, but most importantly, these institutional arrangements place disproportionate emphasis on groundwater. Attaining sustainable groundwater development and use requires new disclosures and narratives in water policy and law, integrating both surface and groundwater resources. The weaknesses identified in groundwater governance need to be taken on Board once, the existing water institutional frameworks open to perfection for sustainable utilisation of groundwater resources

Quantitative and qualitative assessment of groundwater resources for drinking water supply in the peri-urban area of Dhaka, Bangladesh

Groundwater is the primary source of freshwater for drinking, industrial, and agricultural water in many nations worldwide. This vital resource is deteriorating due to rapidly growing urbanization, pollution, overexploitation, and climate change. However, it is unclear how much this specific resource deteriorates over time. Therefore, this study aimed to investigate groundwater resources qualitatively and quantitatively in the peri-urban area of Dhaka, Bangladesh. The study used the modified Mann-Kendall trend test, hotspot analysis, groundwater recharge estimation, multivariate statistical analysis, and the water quality index (WQI) mapping. The trend analysis of groundwater levels indicates that in the most recent year, groundwater levels close to industrial areas have declined at a maximum rate of 1.18 m/year. The estimated groundwater recharge reveals that it is highest (480 mm/year) on rural agricultural land and lowest (220 mm/year) in urban areas. With a 99% confidence level, the groundwater water trend cluster analysis indicates the hotspots of groundwater level depletion near the industrial area. The results showed that Mn, Fe, and As exceeded the World Health Organization's (WHO) recommended limit for drinking water by 76.92%, 61.53%, and 23.07%, respectively. The principal component analysis and hierarchical clustering results indicate that groundwater quality is influenced by rock-water interaction and human interventions. The WQI results suggest that 47.05% of the samples were excellent, 7.69% were good, 9.96% were poor, 17.65% were very poor, and the remaining 17.65% were unfit for drinking purposes. The depletion of groundwater hotspots was identified in northeast region of the study area. Overall, an integrated framework was proposed that offers a holistic approach to sustainable groundwater resource management amid urbanization and industrialization. These findings will provide an essential guideline for groundwater resource management in the peri-urban area of Dhaka city.

Temporal and spatial variations of groundwater quantity and quality for drinking and irrigation purposes in the arid and hot weather of Southern Iran

Groundwater provides a reliable water supply of fresh water worldwide for drinking, agricultural, and industrial purposes, especially in areas where surface water is scarce or unreliable, making it an essential resource for human and economic development. Proper management and protection of groundwater resources are crucial to ensure their sustainability and continued contribution to fulfilling the growing water demand worldwide. This study focused on the quantitative and qualitative changes in groundwater in the Kahoorestan Plain, located northwest of the Persian Gulf in southern Iran. The zoning maps produced by Arc GIS revealed a declining trend in the aquifer level and a drop in the groundwater level of 5.24 m over 20 years. The maps of the flow directions also indicated a general trend from the western highlands to the south and southeast regions of the plain. The Piper diagram showed that the predominant hydrochemical facies of the plain area is NaCl. Temporal changes analysis by the Mann-Kendall test revealed that EC, TDS, TH, Na, Mg, Ca, SO4, and Cl parameters have a rising trend in the majority of wells, which attributes to groundwater over-withdrawal, drought, excessive well drilling, and insufficient aquifer recharge. The study’s analysis of the temporal and spatial changes of the water quality index, Schoeller diagram, and Wilcox diagram revealed that the aquifer’s water quality is unsuitable for drinking and irrigation use due to its high salinity and sodium content. The findings underscore the urgency of adopting effective management strategies to ensure the sustainable management of groundwater resources in the region.