Visual MODFLOW Research Articles

Predictive simulation of groundwater contamination due to landfill leachate: A case study on the Robinson Deep Landfill, Johannesburg, South Africa

Groundwater contamination from municipal solid waste landfills is a global issue, including South Africa. The Robinson Deep landfill (RDL) in Johannesburg lacks necessary leachate collection and handling facilities, has a shallow groundwater table, and no groundwater quality forecast tool. This situation poses a risk of groundwater contamination. This study aimed to construct groundwater flow and contaminant transport models to predict contamination from leachate migration at RDL. Visual MODFLOW Flex software was used for model construction and verification. Heavy metal concentration observations (Al, Cd, Mn, and Pb) from boreholes BH-1, BH-2, BH-3, and BH-H near the RDL were used to calibrate and validate the contaminant transport model (CTM). The result of the CTM predictive simulations for 2030 show Mn and Pb concentrations in the BH-H groundwater could reach 4.28 mg/L and 6.85 mg/L, respectively, exceeding permissible limits of 0.01 mg/L for Pb and 0.4 mg/L for Mn. The simulations indicate that the RDL threatens groundwater quality, especially in the northern areas of the landfill. Based on these findings, a recommendation is made for future studies on assessment and modelling of groundwater quality to focus on areas where increased concentrations of Pb and Mn are predicted. Further, it is recommended that precautionary preventive measures be implemented to mitigate possible contamination of groundwater in the northern areas of the landfill.

Molecular dynamics simulation of modified bentonite and barrier mechanism of phenol pollution in groundwater

In this paper, phenol was used as the target pollutant, and the cutoff walls were prepared with modified bentonite, cement, and sand. Density functional theory (DFT) was used to simulate the modification mechanism of 3-amino-propyl triethoxy silane (APTES) and bentonite. The charge and energy of APTES were discussed, and the graft morphology was simulated. The structure of bentonite was characterized using Scanning electron microscope (SEM) and X-ray Diffraction (XRD) after modification. The spacing of the bentonite layer increased, and the surface of bentonite was folded and stacked, indicating that APTES had been grafted onto the surface of the bentonite. Adsorption kinetics and isothermal tests indicated that modified bentonite's adsorption reaction to phenol aligns more with the pseudo-second-order kinetic model and Langmuir model. According to Computed Tomography (CT) scanning, three-dimensional reconstruction, and Finite element method (FEM) calculations revealed that the effective porosity of the modified bentonite cutoff wall increased significantly, while its permeability coefficient decreased. Through column tests and centrifugal tests, the seepage velocity of phenol solution with different concentrations in the cutoff walls was 10-9m/s. The migration of phenol at a contaminated site was simulated for over 4000 days using Visual ModFlow. The results indicated that the implementation of cutoff wall successfully controlled the migration of phenol.

Visual MODFLOW, solute transport modeling, and remote sensing techniques for adapting aquifer potentiality under reclamation and climate change impacts in coastal aquifer

Global environmental changes, such as climate change and reclamation alterations, significantly influence hydrological processes, leading to hydrologic nonstationarity and challenges in managing water availability and distribution. This study introduces a conceptual underpinning for the rational development and sustainability of groundwater resources. As one of the areas intended for the development projects within the Egyptian national plan for the reclamation of one and a half million acres; hundreds of pumping wells were constructed in the Moghra area to fulfill the reclamation demand. This study investigates the long-term impacts of exploiting the drilled pumping wells under climate change. The approach is to monitor the groundwater levels and the salinity values in the Moghra aquifer with various operational strategies and present proposed sustainable development scenarios. The impact of global warming and climate change is estimated for a prediction period of 30 years by using satellite data, time series geographical analysis, and statistical modeling. Using MODFLOW and Solute Transport (MT3DMS) modules of Visual MODFLOW USGS 2005 software, a three-dimensional (3D) finite-difference model is created to simulate groundwater flow and salinity distribution in the Moghra aquifer with the input of forecast downscaling (2020–2050) of main climatic parameters (PPT, ET, and Temp). The optimal adaptation-integrated scenario to cope with long-term groundwater withdrawal and climate change impacts is achieved when the Ministry of Irrigation and Water Resources (MWRI) recommends that the maximum drawdown shouldn’t be more significant than 1.0 m/ year. In this scenario, 1,500 pumping wells are distributed with an equal space of 500 m, a pumping rate of 1,200 m3/day and input the forecast of the most significant climatic parameters after 30 years. The output results of this scenario revealed a drawdown level of 42 m and a groundwater salinity value of 16,000 mg/l. Climate change has an evident impact on groundwater quantity and quality, particularly in the unconfined coastal aquifer, which is vulnerable to saltwater intrusion and pollution of drinking water resources. The relationship between climate change and the hydrologic cycle is crucial for predicting future water availability and addressing water-related issues.

Assessment of urbanization‐related groundwater flooding process via Visual MODFLOW modeling: A case study for the northern part of Almaty city, Kazakhstan

AbstractGroundwater flooding might be triggered by disregarding hydrogeological processes during urban area development. Such flooding might result in public disruption, engineering infrastructure destruction, and general damage to natural and human environments, as in the northern part of Almaty city. A MODFLOW groundwater flow model was used to simulate and quantitatively assess the changes in hydrogeological conditions affecting the groundwater flooding process. A field study of the Akbulak micro‐district research site showed that groundwater flooding occurred in its center owing to a water table hillock with a total area of 0.07 km2 and groundwater levels ranging from 1.2 to 0.25 m below the ground surface. The MODFLOW simulation suggested that this water table hillock developed from runoff, which, owing to a decrease in natural infiltration across an urbanized area, accumulated in low‐elevation areas and infiltrated. This runoff accumulation effect may be up to eight times the annual average precipitation amount. Once in local sub‐basins, larger runoff volume infiltrates into an underlying aquifer water table that is already high, might cause groundwater flooding in populated areas. The Almaty scenario simulation confirmed the field observations, suggesting that the clogging of the Karasu‐type stream has concentrated runoff to low‐elevation areas and is the leading cause of flooding.

Optimization of Advance Drainage Borehole Layout Based on Visual Modflow

It is an effective measure to prevent water damage in coal mines in order to construct drainage boreholes in water-filled aquifers of a working face roof. The hydrogeological parameters of the roof water-filled aquifer and the parameters of the drainage borehole are closely related to the underground drainage effect. Taking the 3085 working face of the Donghuantuo Mine in Kailuan as an example, the influence degree of hydrogeological parameters and hydrophobic borehole parameters on the amount of drainage water was analyzed using the generalized gray correlation degree. Based on Visual Modflow, the 3D groundwater visualization model was established and the dredging borehole was generalized into the pumping borehole. By changing the main influencing factors, the design optimization of the advanced hydrophobic borehole was discussed. The results showed that the aquifer thickness had a great influence on the amount of water discharged, and the influence degree of the sharp angle between the formation and the direction of drilling, the depth of the final hole, the azimuth angle of drilling, the dip angle of drilling, the elevation of the final hole and the elevation of the borehole on the amount of water discharged decreased successively. Based on the simulation calculation, it could be observed that the hydrophobic borehole should be placed in a position with a larger accumulated thickness of the aquifer to have a better effect of hydrophobic depressurization.

Predicting heavy metal transport in groundwater around Lemna dumpsite: implications for residence utilizing borehole water in Cross River State, Nigeria

Groundwater is considered the most important natural resource to mankind. Groundwater constitutes an important part of the hydrological cycle and is more prone to pollution. Dumpsite located in close proximity to groundwater resources is highly susceptible to leachates pollution. Predicting the susceptibility of groundwater pollution is crucial to address industry-standard codes for groundwater flow, contaminant transport, local to regional-scale water quality, and source water protection issues. Therefore, predicting heavy metal transport in groundwater around Lemna dumpsite in Cross River State, Nigeria, was examined. Soil samples were purposively collected with a soil Auger, along a straight line at (5 m, 25 m and 50 m) in the dumpsite. Water samples were purposively collected from five (5) boreholes close to Lemna dumpsite. The study utilized pumping test method to obtain data for the analysis of heavy metal transport in groundwater. Data analysis of the laboratory results of soil and borehole water quality focuses on arsenic, lead, cadmium, chromium, nickel, and mercury. Paired sample t test was used to analyse the soil and borehole water quality. Visual Modflow was also used to analyse the solute transport of heavy metals in groundwater around Lemna dumpsite. The paired sample t test of the analysis of heavy metals in soil exhibited a significant difference (p < 0.05) compared to National Environmental Standard Regulation and Enforcement Agency limits. The paired sample t test of the analysis of heavy metals in borehole water exhibited a significant difference (p < 0.05) compared to World Health Organization limits. The significant level indicates contamination of the soil and borehole water. The findings revealed a spatial spread of 259.2000 m2/day, with the contaminant travelling up to 94,608 m2/year. The extent of heavy metals concentration exhibited a maximum of 0.991 mg/l to a minimum of (− 6.72 × 10–18 mg/l), with concentrations decreasing as the plume extend. The study recommends the need for remediation and stringent monitoring to mitigate heavy metal contamination of boreholes near Lemna dumpsite.

Modeling and analysis of temporal dynamics in groundwater aquifers of New Valley Oases, Egypt

Water scarcity poses a significant challenge in arid and semi-arid regions, necessitating a focused exploration of groundwater resources. Egypt, confronted with various water challenges, particularly in its Western Desert, relies heavily on groundwater as the exclusive water source due to the presence of the Nubian Sandstone aquifer. Effective groundwater management in this region is imperative. This study delves into the hydrogeological characteristics of the Nubian Sandstone aquifer system (NSAS) in the prominent New Valley Oases—Kharga, Dakhla, and Farafra—where agricultural activities heavily depend on groundwater. The primary objective entails a meticulous temporal assessment of the impact of groundwater development on aquifer behavior, groundwater levels, and drawdown. Employing a remote sensing approach, agricultural expansion from 1995 to 2020 was scrutinized. The Visual MODFLOW package served as a robust tool for simulating groundwater flow in the study areas. Noteworthy findings reveal an upward trajectory in agricultural crop areas, escalating by approximately 6% from 1740 km² in 1995 to 1850 km² in 2020. Concurrently, drawdown, influenced by current groundwater extraction, is anticipated to range from 0.5 to 5 meters per year. To ensure the sustainable development of these areas, stringent regulations must be implemented, underscoring the imperative for judicious groundwater management practices. This research underscores the critical need for informed decision-making and proactive measures to address the evolving dynamics of groundwater resources in the New Valley Oases.

Study on river channel rainwater and flood resources utilization

ABSTRACT In arid regions, the optimal utilization of river channels to collect rainwater resources can effectively alleviate the problem of water scarcity. This paper employs visual MODFLOW software to simulate the infiltration volume of rainwater under different schemes, with the objective of identifying the optimal infiltration volume. The results indicate that the infiltration volume of rainwater is 0.6, 79.7, 36.5, 62, and 10,000 m3 under different design schemes. COMSOL software is employed to simulate the infiltration situation of rainwater under different schemes, and the scheme with the most favourable infiltration effect is identified. The simulation results indicate that scenarios 2, 4, and 5 demonstrate superior early-stage infiltration performance. Ultimately, the optimal infiltration scheme is selected by integrating the infiltration volume, infiltration effect, construction, economic, and ecological factors to achieve the objective of enhancing rainwater harvesting and utilization. This study offers effective and reasonable measures for addressing the challenge of water resources management in arid regions. It provides suitable reference schemes for river channel rainwater storage projects and offers innovative approaches to rainwater resource utilization, thereby contributing to the alleviation of water scarcity in arid areas.

Hydrogeological assessment and contaminant transport modelling of Enyimba landfill site in Aba, Nigeria

ABSTRACT Commercial and industrial growth in cities generates hazardous waste, often disposed of in open dump sites, contaminating groundwater. Understanding pollutant movement and numerical models are crucial for effective water resource management. This study assessed hydrogeological dynamics and pollutant transfer in the Enyimba landfill site, Nigeria, using field surveys and contaminant modelling to understand groundwater quality and arsenic contamination spread. The research technique included field and laboratory experiments, as well as water sampling during both dry and wet seasons, to evaluate groundwater quality. The geochemical examination of groundwater samples revealed the amounts of several metals using atomic absorption spectrophotometry. The study used contaminant transport modelling with Visual MODFLOW Flex 6.1 and MT3DMS software to simulate groundwater flow and solute transport within the aquifer layers. Predictive simulations over a 20-year timeframe demonstrated the progressive spread of arsenic pollution from the landfill, resulting in an ellipsoid-shaped plume stretching from its source. Arsenic levels have gradually increased, posing a serious threat to groundwater quality and human health. The research highlights the need for remedial measures to reduce groundwater pollution, including waste recovery and recycling facilities and geo-membrane use. It emphasizes proactive actions to protect groundwater supplies and promote environmental sustainability in the Enyimba landfill site.

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.

A semi-analytical solution for transient confined-unconfined flow toward the partially penetrating well

In this paper, a semi-analytical solution has been proposed for the transient confined-unconfined flow toward a partially penetrating well in a confined aquifer. It can be used to characterize the dynamic development of drawdown and the transient unconfined region during the transient confined-unconfined conversion. The proposed solution takes into account the delayed response recharge from the unsaturated region by the Neuman's upper surface recharge boundary condition, which is derived by the Laplace and Fourier transformations. The reliability of the semi-analytical solution has been proved by comparisons with numerical solutions from Visual MODFLOW Flex. In addition, a new model for the pumping flow in a pure unconfined aquifer is also developed by degradation analysis of the proposed solution, which has been used to fit well with the measured data from the pumping test in Cape Cod aquifer. The results indicate that both the use of partially penetrating pumping well and aquifer anisotropy have negative effects on the drawdown delayed responses and the development of transient unconfined region, which are disappeared at times &amp;gt;105Srb/Kr. The delayed response is positively related to the gravity storage and vertical hydraulic conductivity.

Simulation of Groundwater Quality in Xi 'an,Shaanxi Province Based on Visual Modflow

The so-called groundwater quality simulation is to study the spatial and temporal variation law of the concentration of a certain soluble substance (element or other component) when it is dispersed and transported by simulation method, to predict the instantaneous dynamics and expansion range of polluted groundwater, and to provide scientific basis for formulating reasonable and effective prevention measures. In recent years, the environmental hydrogeology survey results of some provinces, cities and regions in China show that the groundwater in most cities in China has been polluted to varying degrees. This situation directly affects industrial and agricultural production and people's health. However, in the past, environmental hydrogeology work was mostly limited to surface investigation, lacking quantitative and predictive evaluation research. Monitoring groundwater quality dynamics and forecasting the development trend of groundwater pollution is one of the main tasks of groundwater pollution investigation and research. Relevant information shows that some countries in the world have already carried out this research and established a predictive groundwater quality model. Among them, the United States has established 22 material transport models and 5 heat transport models; France has established 5 models of material transport and 4 models of heat transport. The following countries have only established material transport models: 7 in Israel; 2 in the UK; 2 in Canada; 1 in West Germany and 1 in Japan. Therefore, we believe that the study of groundwater quality simulation experiment, which is still blank in China's scientific field, has become an important subject that needs to be carried out urgently to ensure the four modernizations and people's health. The hydrogeological conditions and dynamic characteristics of groundwater resources have been comprehensively analyzed and studied. It points out that the continuous exploitation of groundwater resources in 2018 has led to the deterioration of groundwater quality, land degradation, underground, cracks and depletion of groundwater resources, and puts forward some preventive measures.

The impact of the embankment and the recreational lake on capturing front with drilling wells

This paper presents the influence on the levels from the well caption front Gherăeşti-Bacău, located on the right side of the Bistrița River, through the construction, on the right shore, of a 2.25 km long perimetral embankment, and a recreational lake with a surface of 3.18 hectares and average depth of 5.5 m (Figure 1). Through numerical modelling, using the modelling software of Visual Modflow aquifer, the influence on the hydrostatic level from drilled wells was determined, as well as the influence on the phreatic flow through the making of the recreational lake, which captures a part of the underground water. The use of the mathematical model allows the determination of the optimal parameters for an extraction from the aquifer known through classical methods. To achieve the mathematical model the method of filtration resistances was used, which is applied in the case of a sudden curvature of the streamlines (in the proximity of the imperfect permeable/impervious borders: channels, drains, well systems, screens), hence they are applied during pressure/level drops. This method allows the following equalizations: the imperfect wells can be considered as perfect; the lines of perfect/imperfect wells can be considered as perfect trenches (channels) with a flow equal to the sum of all wells; a stratified aquifer (up to 3 layers) can be equivaled with a homogenous one. Aspects regarding the flow were taken into consideration: with a free level or under pressure, the dimensioning of the model, the initial conditions of the aquifer layer, the lithostratigraphic characteristics, homogeneity, anisotropy, the transfer mechanisms in the domain’s interior, the studied hydrogeological structure was schematized, having done a monolayer model. The calibration of the model consists of adjusting, in reasonable conditions, of the domain data (the permeabilities), boundary conditions, so that through the running of the model and obtaining the corresponding piezometric lines and the obtained data will overlap the levels of the existing drillings.

Study on the Contribution of Groundwater Nitrogen Pollution Sources in a Typical Section of the Wei River in China

Aiming to assess the groundwater nitrogen pollution problem in a typical section of the Wei River in China, the contribution of groundwater nitrogen pollution sources in the region was studied. Using Hydrus-1D to implement the simulation process of substituting points for surfaces, we calculated the volume and nitrogen concentration of the water leaching out from the bottom of the encompassing aeration zone. The results of the Hydrus-1D simulation were input as initial values into the nitrogen migration and transformation numerical model constructed using Visual MODFLOW to integrate the simulation calculations between the surface, the aeration zone, and the aquifer system. In addition, the contribution rates of different groundwater nitrogen pollution sources were calculated using the equilibrium formula combined with the groundwater nitrogen test results. The simulation results showed that the groundwater nitrogen in the southern part of the Wei River comes from two main sources: vertical infiltration and river recharge. Specifically, ammonia nitrogen vertical infiltration and river recharge contribute 95.82% and 4.18%, respectively; nitrite nitrogen vertical infiltration and river recharge contribute 92.41% and 7.59%; and nitrate nitrogen vertical infiltration and river recharge contribute 94.26% and 5.74%. According to the simulation results, an increase in the intensity of surface water pollution control is required in the study area. It is also necessary to control the use of nitrogen fertiliser on farmland in the study area and improve the utilisation rate of nitrogen fertiliser to reduce the nitrogen pollution loads from these sources.

Numerical simulation of the interaction between mine water drainage and recharge: A case study of Wutongzhuang coal mine in Heibei Province, China

Water inflow poses a critical safety concern in coal mining. The pressing challenge in current mine water inflow research is the need to enhance the prediction of dynamic changes in mine water inflow across different mining stages. In this study, the hydrogeological conditions and aquifer structural characteristics of the Wutongzhuang Coal Mine in Hebei Province, China were analyzed, and the results were combined with pumping test and drilling data. A numerical model of groundwater flow in the study area was established using Visual MODFLOW and the model was calibrated and verified by comparing its results with the measured values to ensure that it realistically reflected the state of groundwater movement in the study area. The results of numerical simulation indicated that: (1) The water level of the Ordovician aquifer varies significantly by season. A large exposed area of Ordovician limestone in the western mountainous region receives a large amount of rainfall infiltration recharge in the summer rainy period that raises the water level of the Ordovician aquifer in the study area. (2) The groundwater system in the study area is in an equilibrium state, with the water inflow approximately equal to the outflow. (3) The recharge of mine drainage water has a slight positive effect on the Ordovician water level and the floor water inflow, with the impact on the water level of the aquifer decreasing as the distance from the recharge well and the import of Ordovician limestone water increase. In cases in which there is mine water recharge, the water level of the Ordovician aquifer is approximately 0.33 to 1.37 m higher than in cases without recharge, resulting in an increase in water inflow of approximately 10.6 m3/d. (4) In cases in which there is recharge of all drainage water, the maximum water inflow into the fifth mining area is 3,491.3 m3/d, which is 12.5 m3/d higher than in the case without recharge. These results provide important technical references for the formulation of mining schemes and water prevention measures in mining areas.

A PERMANENT MATHEMATICAL MODEL OF FILTRATION AND MIGRATION CONDITIONS BETWEEN THE PRIPYAT AND UZH RIVERS OF THE CHORNOBYL EXCLUSION ZONE

Background. Over the past 8–10 years, the radio-hydroecological and hydrogeological conditions of the Chornobyl Exclusion Zone have changed significantly. Under the influence of the decommissioning of the water-containing cooler, the levels, speed and direction of movement of groundwater have changed on a regional scale. New radiation-hazardous objects were created: Storage of spent nuclear fuel (SSNF-2) and Centralized storage of spent nuclear fuel (CSSNF). The impact of climate change on the regime of water bodies has also increased. To study the impact of radiation-hazardous objects on the water environment of the exclusion zone, to forecast changes in hydrogeological conditions under the influence of climate change and man-made loads, it is necessary to create an updated model of filtration and migration conditions with the possibility of its further adjustment and improvement. Methods. In creating and developing a constant mathematical model based on the finite difference method, the geological and hydrogeological conditions of the research area were considered. Spatial constructions were also carried out to visualize the geological structure using GIS technologies. The filtering scheme was drawn up for computational operations. The QGis program was used to construct the surfaces of geological horizons, and the Visual MODFLOW program was used to develop the filtration model. Results. A model of filtration and migration conditions of the Pripyat-Uzh interfluve of the Chornobyl Exclusion Zone was constructed. The distribution of groundwater levels and heads in the Buchach aquifer was obtained. Forecasts of the paths, directions and time limits of the spread of pollutants with underground water from radiation-hazardous objects have been made. We carried out forecasts of the impact of changes in the boundary conditions of the aquifer on the hydrodynamic parameters of groundwater to justify project decisions on improving the network of observation wells and determining the conditions of flooding of the Chornobyl nuclear power plant site. Forecasts of the impact of global warming on the underground water regime have been carried out. Conclusions. The forecast field of pressure distribution demonstrates the possibility of improving the radiological state of groundwater as a result of: increasing the thickness of the aeration zone and its sorption capacity and accelerating self-purification due to the growth of underground flow gradients. It is important that the unloading of polluted groundwater will not take place in the Pripyat River, but in the isolated residual lakes of the former cooling pond. It will take about 20 years for groundwater to reach the lakes from the Chornobyl nuclear power plant site.

SIMULATION OF GROUNDWATER POLLUTION IN A FACTORY BASED ON VISUAL MODFLOW

The groundwater pollution situation of an industrial park in Mengzhou City, Henan province was simulated to provide reference for groundwater pollution migration and prevention. Through various experiments and hydrogeological surveys to obtain basic parameters for simulation work, this paper uses Visual Modflow software to establish groundwater numerical model in the study area, and on this basis, MT3DMS module is used to simulate solute transport of leaked pollutants COD and NH3-N. In this paper, solute transport is simulated under two working conditions: under abnormal working conditions, the influence range and maximum transport distance of pollutants in sewage transport pipeline leakage without seepage prevention measures; Sewage transport pipeline leakage but seepage prevention measures in the case of pollutant diffusion.

Assessment of future groundwater levels using Visual MODFLOW in the Gomti River basin in India

Assessment of future groundwater levels using Visual MODFLOW in the Gomti River basin in India

Experimental and numerical investigation of Engineered Injection and Extraction (EIE) induced with three-dimensional flow field

Abstract In situ groundwater remediation technique is a commonly adopted method for the treatment of contaminated groundwater and the porous media associated with it. Engineered Injection and Extraction (EIE) has evolved as an improved methodology for in situ remediation, where sequential injection and extraction of clean water around the treatment area enhances the spreading of treatment reagents by inducing additional flow fields. Conventional EIE studies were based on flow fields in two dimensions. There are only limited experimental and theoretical studies exploring the potential of inducing a three-dimensional flow field using EIE. The present study experimentally and numerically evaluates the effect of a three-dimensional flow field induced by partially screened wells. EIE experiments were conducted on a laboratory-scale aquifer model with laterite soil as the porous medium. Tracer transport in porous medium was studied by measuring the concentration at various observation points and enhanced dilution was observed when EIE was employed with partially screened wells. Experimental observations were also used to calibrate and validate the numerical model developed using Visual MODFLOW Flex. Enhancement in spreading was quantified in terms of concentration mass attenuation and maximum mass attenuation was observed when EIE was employed with partially screened wells.

Groundwater sustainability assessment under climate change scenarios using integrated modelling approach and multi-criteria decision method

Groundwater is the main preferred source of freshwater resources and therefore its use, management, and sustainability are closely related to the Sustainable Development Goals (SDGs). Escalating water demands along with climate change scenarios has raised serious concern over groundwater sustainability in the state of Rajasthan in India. It put further challenges to fulfill regional-level sustainable development targets. The present study is focused on assessing groundwater sustainability under RCP 4.5 and RCP 8.5 scenarios using an integrated modelling approach for the Khari River basin. For hydrological assessment, the SWAT model was selected to obtain recharge and evapotranspiration in the historical and future periods. The results showed that average recharge will decrease in the RCP 4.5 from 119.4 mm in the decade 2011–2020 to 57.30 mm in the decade 2040–50, and 108 mm in RCP 8.5. The Visual MODFLOW model was also used to estimate the future groundwater level in the basin using recharge & evapotranspiration data, hydrogeological data, and groundwater level for the basin. Under Multi-Criteria Decision Methods (MCDM), the Shannon Entropy method was selected for weightage, and the results showed that hydrology is the most important factor according to the weights obtained. TOPSIS result shows that sub-basin 1 and sub-basin 5 are at the lower ranking based on the groundwater sustainability index in comparison to the other three sub-basins in 2011–2020 as well as in 2040–2050. The sub-basins need better management and conservation practices to achieve SDGs components for groundwater sustainability.