Groundwater Protection Zones Research Articles

Terrestrial land use signals on groundwater fauna beyond current protection buffers.

Terrestrial and aquatic ecosystems are tightly linked, with direct implications for applied resource management and conservation. It is well known that human land use change and intensification of terrestrial systems can have large impacts on surface freshwater ecosystems. Contrastingly, the study and understanding of such land use impacts on groundwater communities is lagging behind. Both the impact strength of land use on groundwater communities and the spatial extents at which such interlinkages are operating are largely unknown, despite our reliance on groundwater for drinking water extraction as a key ecosystem service. Here, we analyzed groundwater amphipod occurrence from several hundred shallow groundwater aquifers used for drinking water extraction across a region of varying agricultural intensity and human population density in Switzerland. Despite drinking water extraction sites being generally built at locations with expected minimal aboveground impacts on water quality, we found a direct correlation between land use type and intensity within the surrounding catchment area and the locally measured nitrate concentrations, which is a direct proxy for drinking water quality. Furthermore, groundwater amphipods were more likely to be found at sites with higher forest coverage than at sites with higher crop and intensive pasture coverages, clearly indicating a tight connection between aboveground land use and groundwater biodiversity. Our results indicate that land use type effects on groundwater communities are most relevant and pronounced to spatial scales of about 400-1000 m around the groundwater sampling site. Importantly, the here identified spatial scale is 1.2- to 3-fold exceeding the average extent of currently defined groundwater protection zones. We postulate that incorporating an ecosystem perspective into groundwater management strategies is needed for effective protection of groundwater quality and biodiversity.

Strategies for Sustainable Water Management

Groundwater in the Rania basin, Iraqi Kurdistan region, has been under intensive exploitation in the last two decades, where quantity and quality are both affected. Hence, any attempt to protect the aquifers has become an urgent need. Saruchawa, Qulai Rania, and Qulai Kanimaran are the three large springs, among dozens of others in the area, that are heavily relied on as the sole or main source of water supply. Hydrochemical analysis, the first and most practical step to evaluating the water quality, was carried out through 60 water samples collected from 13 springs and 17 wells in both dry and wet seasons (October 2018 and May 2019). Laboratory results show a high calcium bicarbonate concentration with weak acids’ dominance. Protection zones are delineated for these springs using aquifer susceptibility to contamination and analysis of the recession part of the spring curves. The equivalent relationship between the protection factor (Fp) produced by the Epikarst, protective cover, infiltration condition, and Karst network development mapping method and the groundwater protection zone (S) is considered. Qulai Rania and Kanimaran Springs are mapped to be in S2 (a highly vulnerable area), whereas Saruchawa Spring is located in S1 (very highly vulnerable). Based on the second method results (recession curve analyses), all three selected springs fall under the (D-type) vulnerability category. As a result, the immediate protection zone was going to be surrounded by the inner protection zone, and both are enclosed within the outer protection zone, which covers the remainder of the catchment area.

Modeling groundwater recharge potential zones in the Wadi Yalamlam, Saudi Arabia

Effective management of groundwater resources is vital in arid and semi-arid regions like the Yalamlam Basin. Identifying appropriate places for groundwater artificial recharge is key to addressing water shortages and guaranteeing the long-term viability of aquifers. By combining the Analytical Hierarchy Process (AHP) approach with GIS technology, this research offers a thorough framework for evaluating the potential for groundwater recharge. Data collection for the study includes lineament density, slope, drainage density, rainfall, Land Use/Land Cover (LU/LC), soil, elevation, and TWI, among other crucial variables. In this study, lineament density, slope, drainage density, rainfall, LULC, soil, elevation and TWI are the most sensitive characteristics with relative weights of 30, 23, 16, 11, 8, 5, 4 and 3%, respectively. According to the study’s findings, there are many zones in the Yalamlam region with varying capacities for groundwater recharging. Based on the locations that may be used for groundwater recharge, the study’s findings were categorized into five groups: very high (12.7%), high (23.3%), moderate (29.6%), poor (24.4%), and very poor (10%). The validation of the groundwater protection zones was conducted by using eight wells in the basin. As part of the validation process, the Total Dissolved Solids (TDS) in the boreholes and the groundwater protection zones (GWPZs) were compared. A strong positive correlation was found between them (0.61). The results of this research can be used for the management of groundwater resources and provide valuable information for the creation of policies that focus on specific actions to boost groundwater recharge. These findings may considerably enhance the effectiveness of efforts aimed at implementing customized methods to encourage groundwater recharge. The results suggest that there are substantial prospects for using artificial recharge in groundwater management and planning to tackle the issue of groundwater availability in the study region.

Groundwater recharge potential zone modeling in the Wadi Al-Lith Basin, Saudi Arabia

The management of groundwater resources is crucial in arid and semi-arid regions such as Al-Lith Basin, and therefore, the identification of suitable areas for groundwater recharge is important in solving the problem of water scarcity and ensuring the long-term sustainability of aquifers. In this study, the Analytic Hierarchy Process (AHP) technique, in conjunction with GIS, was applied to locate potential zones for groundwater recharge in the Al-Lith basin. The research methodology includes collecting the essential data, including lineament density, slope, rainfall, drainage density, LU/LC, soil, elevation, and TWI. AHP is used to assign relative weights to different qualities, considering their significance in influencing groundwater recharge. The ArcGIS was employed to process and analyze the weighted layers, which resulted in the creation of a comprehensive map illustrating the potential for groundwater recharge. The study results suggested that the Al-Lith Subbasin has several zones that exhibit different levels of groundwater recharge capability. The results obtained from this study indicated that 12.83% of the basin area has significant groundwater recharge potential zones (GWPZ), ranging from high to very high levels. The groundwater recharge potential zones in the basin are categorized as very poor to poor, covering 19.4% of the area, while the moderate groundwater recharge potential zones represent 67.77% of the basin area. The groundwater protection zones were validated using 19 wells distributed across the basin. The validation findings indicate there is an overlap between the GWPZ classes and the wells in the specified location. Overall, the findings of this study can enhance groundwater resource management and inform policy development for targeted interventions aimed at enhancing groundwater recharge.

Enhancing groundwater recharge in drinking water protection zones in Flanders (Belgium): A novel approach to assess stormwater managed aquifer recharge potential

Study regionFlanders (Belgium) Study focusStormwater infiltration for managed aquifer recharge is increasingly recognized as a drought adaptation measure. Given the high degree of urbanization and imperviousness, stormwater infiltration has significant potential in Flanders (Belgium). This research presents a novel approach to quantify stormwater availability and its potential to enhance groundwater recharge. Stormwater volumes available for recharge are calculated based on the imperviousness level, yearly average precipitation volumes, and runoff coefficients. This study focuses on groundwater protection zones around drinking water wells to assess the role of increased infiltration for sustainable drinking water production. Calculated potential stormwater volumes for recharge are compared to natural groundwater recharge and pumping volumes for drinking water production to quantify the potential significance of stormwater infiltration for aquifer recharge. New hydrological insights for the regionResults show a high potential for stormwater infiltration in Flemish protection zones with an average of 17% (7%-33%) additional groundwater recharge from stormwater infiltration. Additionally, stormwater recharge could potentially compensate for 19% (8%-37%) of abstracted drinking water production from phreatic aquifers. Locally, higher groundwater recharge potentials were calculated, especially in protection zones around the city of Leuven. Therefore, stormwater harvesting for infiltration and groundwater recharge should be further encouraged throughout the region, with special attention to urban areas. However, further research is needed on stormwater quality to assess groundwater quality risks in this water quantity-quality balancing exercise.

Geochemical Characteristics and Controlling Factors of Groundwater Chemical Composition in the Zihe River Source Area, Shandong, China

The geochemical characterization and evolution of shallow groundwater in the Zihe River source area is a key issue that needs to be addressed. In this study, a combination of traditional geochemical techniques and geochemical modeling was used to explain the geochemical processes and major ion sources in the chemical evolution of shallow groundwater in the Zihe River source area, Northeast China. Fifty-seven water samples were collected in June 2020 for chemical analysis, and the results showed that the main groundwater chemistry types in the three major aquifers are HCO3·SO4-Ca·Mg-type pore water from loose quaternary rocks, HCO3·SO4-Ca·Mg-type karstic fissure water from carbonate rocks, and HCO3·SO4-Ca-type weathered fissure water from massive rocks. Water–rock interactions in alkaline environments were the main causes of changes in groundwater chemistry. Rock weathering dominated the geochemical evolution of each aquifer. The analysis of ion concentration ratios and modeling revealed that the aquifer’s chemical components are mainly derived from the dissolution of dolomite and calcite and partly from the infiltration of pollutants containing Cl− and NO3−, as well as from the dissolution of quartz. Mg2+ is derived from the dissolution of dolomite. HCO3− is primarily derived from the co-dissolution of calcite and dolomite, and to a lesser extent, its content is also influenced by the recharge of rainfall. SO42− has two sources: it mainly originates from the dissolution of gypsum and the anhydrite layer, followed by atmospheric precipitation. The synthesis showed that the groundwater quality in the source area of Zihe River is good, all the indices reached the standard of class III groundwater quality, and the overall degree of human pollution is low. The results of this research will provide a scientific basis for the local authorities to delineate karst groundwater protection zones in the Zihe River source area and to formulate resource management strategies for the development, utilization, and protection of karst groundwater.

Geostatistical estimates of groundwater nitrate-nitrogen concentrations with spatial auxiliary information on DRASTIC-LU-based aquifer contamination vulnerability.

Groundwater nitrate-nitrogen contamination typically involves several natural and anthropogenic factors, including those related to hydrology, hydrogeology, topography, and land use (LU). DRASTIC-LU-based aquifer contamination vulnerability could be used to characterize the pollution potentials of groundwater nitrate-nitrogen and to determine groundwater protection zones. This study used regression kriging (RK) with environmental auxiliary information on DRASTIC-LU-based aquifer contamination vulnerability to investigate groundwater nitrate-nitrogen pollution in the Pingtung Plain of Taiwan. First, the relationship between groundwater nitrate-nitrogen pollution and assessments of aquifer contamination vulnerability was determined using stepwise multivariate linear regression (MLR). Subsequently, the residuals between the nitrate-nitrogen observations and MLR predictions were estimated by kriging techniques. Finally, the groundwater nitrate-nitrogen distributions were spatially analyzed using RK, ordinary kriging (OK), and MLR. The findings indicated that the land used for orchards and the medium- and coarse-sand fractions of vadose zones were associated with groundwater nitrate-nitrogen concentrations. The fertilizer used for orchards was identified as the primary source of groundwater nitrate-nitrogen pollution. The RK estimates could be used to analyze the characteristics of the pollution source for land used for orchards and exhibited high spatial variability and accuracy after residual correction. Moreover, RK had an excellent estimate ability for extreme data compared to MLR and OK. Correctly determining groundwater nitrate-nitrogen distributions using RK was useful for administering environmental resources and preventing public health hazards.

Some Legal Options to Ensure the Protection of South Africa's Utilisable Groundwater Resources

Groundwater, which is water that is found underground, is less susceptible than surface water resources to evaporation, and thus offers resilience against the impacts of climate change. Many South African cities, communities and farmers depend on groundwater for domestic or other socio-economic purposes. This implies that groundwater resources which are currently or potentially utilisable should be identified, and suitable legal measures should be implemented to protect these resources from potential risks of harm or damage posed by anthropogenic activity. This article firstly evaluates the effectiveness of the country's existing regulatory framework to effectively protect South Africa's groundwater resources and finds that the framework can be improved upon significantly. Secondly, it explores regulatory opportunities within the existing legal framework to strengthen South Africa's groundwater governance regime, including making use of land-use planning instruments to facilitate the implementation of groundwater protection zones.

Application of Particle Trace Morphology and Sensitivity Analysis in Delineation of Drinking Water Protection Zone in the Luan River, North China

The appropriate division of underground drinking water source protection zones is a low-cost method of preventing water source pollution and ensuring a supply of safe drinking water. Based on FEFLOW, a groundwater flow model of large water sources was established for Luan River, North China. Trace lines of particle reverse migration for 100 and 1000 days were obtained by random walks. According to the trace morphology, the water sources in the riverside water source area were divided into four categories. The first- and second-grade protection areas were delimited by ArcGIS, with areas of 0.375 and 1.20 km2. The local and global sensitivity of the permeability coefficient (K) and effective porosity (ne) effects on the area of groundwater protection zones were calculated. The area of the protection zones was positively correlated with K and negatively correlated with ne. The variation in the protected zone caused by the simultaneous changes in K and ne is the same as that of ne alone, and the global sensitivity is closer to the local sensitivity of ne. This indicates that ne has a greater impact than K on the scope of groundwater protection zones. Moreover, global sensitivity is not simply a superposition of local sensitivity, and the interaction between parameters can reduce the effect of a parameter acting alone on the delineation of protection zones. This also shows that the global sensitivity is closer to the actual situation than the local sensitivity, thus providing a scientific basis for the delimitation and monitoring of water source protection zones.

On using lumped-parameter models in groundwater protection zones to predict aquifer response to reduced agrochemical input

• Waiting times for aquifers contaminated by agrochemicals are useful for management. • Lumped-parameter models can be used to estimate these waiting times. • Waiting times useful for management must not be confused with mean transit times. In groundwater protection zones, water managers and water providers will typically need to know the time scale of recovery for aquifers contaminated by agrochemicals. Despite the large body of work on the topic in the scientific literature, there still seems to be some need to clarify which waiting times are most relevant for water management planning, and how they relate to metrics such as the mean transit time of tracer. Firstly, we propose a simple nomenclature for the different waiting times and how they relate to the evolution of agrochemical concentration (increasing and decreasing concentration trends, trend reversal, etc.). Secondly, we describe how to select and fit a lumped-parameter model to contaminant time series and environmental isotopes in order to characterize aquifer response to agrochemical contamination. Thirdly, we explain how waiting times can be calculated from the fitted lumped-parameter model. Finally, we present a case study focussing on the contamination of several springs of the city of Luxembourg by a fungicide transformation product combining environmental tracers and pesticide measurements. We find that on the study site, the parameters estimated separately from the environmental tracers and from the pesticide data are nearly the same although they correspond to different areas within the groundwatershed. Although this could be incidental, it might also indicate that robust waiting time estimates can be obtained from agrochemical time series and environmental tracer measurements, at least in simple cases.

Hydrogeology of a complex karst catchment in Southern Dalmatia (Croatia) and Western Herzegovina (Bosnia and Herzegovina)

ABSTRACT Our study focuses on a sizeable transboundary karst catchment in Croatia and Bosnia and Herzegovina, extending over 2000 km2. A complex underground conduit system and extreme karst forms heterogeneity are the main characteristics of the area in question. Since determining the boundary of such a large and complex catchment is difficult, we used different kinds of data sets, of which the most relevant are the available geological data, hydrochemical data, hydrological data, and tracing tests data, to divide the regional catchment into six subcatchments. We also examined past archived reports and carried out new hydrological investigations of several major and minor springs. Our research results in a hydrogeological map that can be used as a base for establishing site-specific groundwater protection zones, for water balance calculations and the planning of new research in this area, especially the ones regulating combined cross-border efforts to prevent groundwater contamination and ensure sufficient drinking water.

Delineating the groundwater protection zone (GPZ) around a water supply plant in Bekasi, West Java, Indonesia

The escalating community demands for water supply in urban areas lead to overexploitation on groundwater and worsening the condition of the resources. These exploitation activities will affect the quality, quantity, and continuity (QQC) of groundwater, especially those that are produced as the resource for the water supply industry. The study area is a water supply industry plant located in Bekasi, West Java, Indonesia, that uses groundwater originating from the Bekasi–Karawang Groundwater Basin. Proper management is needed to maintain the QQC of the groundwater, and one of the steps in pursuing it is with the Groundwater Protection Zone (GPZ) delineation. The aim of this study is to delineate the GPZ in the study area based on the natural conditions and the conceptual hydrogeological models. The method used to delineate the GPZ is groundwater flow modelling. As a result, this study identifies the unconfined and confined aquifers systems at the plant, while the groundwater extraction is only sourced from the confined aquifer. Our findings reveal that the groundwater in both unconfined and confined aquifers generally flows in a south-north direction with the travel time varying from 25 days to 133 years. The GPZ resulted for the water supply plant consists of the production well protection zone and the recharge area protection zone. This study also suggests recommendations for groundwater management in the GPZ based on the source of contaminants.

Delineating springs safeguard zones with DISCO-URBAN index: a valuable tool for groundwater vulnerability mapping in local-scale urban areas

Assessing groundwater vulnerability to contamination is vital worldwide, particularly in sustainable water resources management. That is mainly a concern in fractured media in urban areas due to a large diversity of contaminant sources and the complexity of recharge pathways. Thus, groundwater vulnerability assessment is essential to delineate groundwater protection zones around springs or wellheads. Furthermore, it considers the groundwater system’s heterogeneity and the surrounding hydrogeological conditions, as well as provides suitable solutions to protect the resource and mitigate potential hazards. DISCO-URBAN index focused on urban areas was applied to evaluate the intrinsic vulnerability in fractured media in the surroundings of Penafiel city (NW Portugal). The analytic hierarchy process (AHP) was used to determine the weight of each evaluation factor. Furthermore, multi-criteria indexes were applied: GOD‐S, DRASTIC‐Fm, SI DISCO and DISCO-URBAN. Low to moderate vulnerability classes dominate in the combined approach of the vulnerability indexes. However, very high vulnerability classes occur in DISCO and DISCO-URBAN, corroborated by the water-enriched nitrates. Therefore, the DISCO-URBAN method highlights a better delineation of groundwater safeguard zones. In fact, the DISCO-URBAN index is reliable in urban areas to be integrated as a tool to develop local site hydrogeological investigations related to springs safeguard zones.

Water Security Needs What Ought to Be Done to Increase the Future Water Security as a Fundamental Base for Social, Economic and Political Stability—The Case of Jordan

This study discusses the present water security situation in Jordan and delineates the required policies and programs to reach at a more robust and resilient water security situation. Although Jordan has achieved much in securing the different components of its water sector system, some components have still to be adequately addressed and others strengthened. Increasing the available water resources, which is practically only possible by desalinating sea water at Aqaba under sole Jordanian sovereignty, is found to be the most important and vital issue in improving the country’s water security situation. It improves the security issues of providing dearly needed additional water, releases the overexploited aquifers and saves them from depletion and quality deterioration, allows introducing new industries to Jordan, de-sharpens the conflict on the shared water resources with Jordan’s neighboring countries and is expected to render these conflicts to a problem of royalty on water resources and not as it is at present a social, economic, human, environmental and political conflict. Desalination will also make Jordan more resilient to climate change. Infrastructure security must be strengthened in Jordan both against natural hazards and against intended sabotage and damage. Water quality protection from pollution and deterioration has still to be adequately addressed requiring strengthening of laws and regulations and their application. The already delineated surface and groundwater protection zones have to be strictly adhered when licensing human activities in addition to implementing cybersecurity best practices. In addition, technology-dependent management tools have to be strongly advanced using integrated water resources management to ensure sustainable resource management, detection and repair of physical water losses and illegal water tapings, pricing water at its opportunity cost, irrigation modernization, strict environmental impacts assessment and application wherever water resources and water infrastructures are involved, and strengthening of training and management programs.

Groundwater Recharge Assessment using Geographic Information System APLIS Method in Donorojo Karst Area, Pacitan

Karst aquifers can be a source of water supply, especially for the community in Donorojo District, which is one of the areas with the worst drought crisis in Pacitan Regency and requires a sustainable solution to the problem of water needs. Therefore, the study and management of karst formations are very important because of their abundance and potential in forming subsurface aquifer karst aquifers. The recharge rate is one of the basic parameters in the management of the consumption and maintenance of this resource. In addition, the distribution of aquifer locations, aquifer characteristics, and the quality of groundwater forming the aquifer need to be known. This study aims to assess aquifers in the Karst area of Donorojo, Pacitan based on recharge rate and spatial distribution. The APLIS method can estimate surface recharge rates and present the results as a map of the spatial distribution of aquifer recharge rates by utilizing a Geographical Information System (GIS). The results of the analysis using the APLIS method, the groundwater recharge rate in the Donorojo Pacitan karst area is divided into 4 classes, namely very low, low, moderate, and high. Almost the entire Donorojo karst area has a high groundwater recharge rate, this means that the area needs to be used as a groundwater protection zone and it is important to carry out good groundwater management, especially to overcome the problem of drought.

Application of the APLIS Method for Groundwater Vulnerability Assessment in Rote Island Karst Areas

The karst area on Rote Island dominates more than 60% of the Island. The land surface conditions in karst areas are generally dry, while below the subsurface is the potential for abundant water resources. This study aims to assess groundwater vulnerability using the APLIS (Altitude, Pendiete/Slope, Lithology, Infiltration, and Soils) method that will integrate with Geographic Information System (GIS) technique. The parameters used are elevation, slope, lithology, infiltration zone, and soil type. Slope and elevation are obtained from DEM maps, the soil is obtained from soil type maps, while lithology and infiltration zone are obtained from geological maps. The lithology and the infiltration zone in APLIS method analysis have a high role in determining the level of groundwater vulnerability. The groundwater vulnerability in Rote Island was divided into four classes: very low in the Northeast, low in the South, moderate in the East and North, and high in the East and West part of the Island. It explains that a high level of groundwater vulnerability in Rote Island needs to be used as a groundwater protection zone.

DISCO-Urban: an updated GIS-based vulnerability mapping method for delineating groundwater protection zones in historic urban areas

DISCO-Urban: an updated GIS-based vulnerability mapping method for delineating groundwater protection zones in historic urban areas

The EPIK multi-attribute method for intrinsic vulnerability assessment of karstic aquifer under semi-arid climatic conditions, case of Cheria Plateau, NE Algeria

Karst aquifers supply an important freshwater resource for MENA (Middle East and North Africa) semi-arid regions. Their functioning conditions reveal often several contaminations. The Cheria carbonate aquifer (NE Algeria) has never had management tools to deal with the pollution of this resource. The outlining and protection of the vulnerable areas are essential to ensure the water purity and the consumer health. Based on the EPIK multicriteria analysis method, we aim in our study to assess the karstic aquifers intrinsic-vulnerability to contamination in the Cheria Plateau. This method has been already applied for contamination problems in Northeast Algeria. It uses a conceptual scheme that considers epikarst, protective cover, infiltration, and karst network as parameters. In addition, it also uses the interpolation of the geophysics data to define the conditioning attributes. The resulting vulnerability map categorizes all the basin vulnerable areas and the groundwater protection zones. Nearly 30% of the study area was judged as highly vulnerable to anthropogenic pollution, whereas around 10% is moderately vulnerable. These results confirm that the karst aquifer of the Cheria Plateau is severely polluted by chemical pesticides resulting from farming activity. In addition to the surrounding agricultural lands, the underground of Cheria city was found as extremely vulnerable to pollution (F < 19). Our study delimited boundaries for the karst aquifer protection zones and for an integrated resource management in this region. It recommends applying this method for comparable problems.

Determination of protection zones in drinking water basins: a case study from Turkey, Sapanca Lake Basin

To prepare specific protection and policies for drinking water basins is important for providing sustainable drinking water management. In this study, a decision support system composed of hydrogeological, hydrogeochemical, soil type and topological parameters was applied to define the protection zones. Littoral zone and slope parameters in topology, the grain size in soil media, hydraulic conductivity, aquifer type and well parameters in hydrogeology, hydrogeochemical and isotopic assessment were used to create protection zones in the decision support system based on the Geographic Information System. Identifying hydrological resource areas, and determination of residence time and recharge altitude in groundwater were done using hydrogeochemical parameters and isotopic tracers. The GIS platform was used to evaluate the maps generated from the parameters and to apply reclassification and overlapping methods. The proposed methodology was applied to the Sapanca Lake Basin in Turkey since the lake is one of the most crucial drinking water lakes in Turkey. According to the proposed methodology, green belt, wellhead, absolute, short-range groundwater protection, short and medium-range protection zones were defined in the basin. The absolute protection zones in the basin are distinctively the areas covered with karst structures which are dolines and swallow holes.

Integration of borehole and vertical electrical sounding data to characterise the sedimentation process and groundwater in Krueng Aceh basin, Indonesia

This research aims to determine the characteristics of sediment and aquifer layers beneath the surface based on borehole data and the Vertical Electrical Sounding (VES) method as well as to map the groundwater protection zone for future generations. Thirty boreholes were analysed to determine sediment grain size and its structure at every depth up to 200 m beneath the surface. Six locations of VES were performed to confirm the presence of groundwater at every depth of lithology. The spatial analysis was used to scrutinize sand to clay ratio distribution of the boreholes data from which map of the groundwater protection zone of the study area was developed. The results reveal that the characters of sedimentation in the Krueng Aceh basin are influenced by terrestrial and coastal processes at a depth of −200 m below modern mean sea-level (MSL). Historically, the sedimentation process beneath −160 m is highly related to the Last Glacial Maximum (LGM) event and sea-level fluctuation in Southeast Asia. The VES findings denote the clayey sands, sands, and gravel strata discovered in borehole functioning as aquifer layers and they are indicated by low resistivity value. The sand to clay ratio distribution mapping indicates that the centre part of the basin is the water resources zone, and it should be protected for future generations.