High Groundwater Potential Zones Research Articles

Mapping of heterogeneity on groundwater level and potential zones along expeditiously urbanizing tropical coastal regions

The study of coastal groundwater potential is critical as freshwater availability is under tremendous stress due to increased coastal region development and noticeable monsoonal changing patterns over time. In addition to these factors, Odisha's coastal region has a larger drainage network in low-lying plains, which reduces freshwater recharge by increasing surface discharge. To sustain freshwater usage, the demarcation of the Groundwater potential zone (GWPZ) was done using Geographic Information System (GIS), Analytical Hierarchy Process (AHP), and Multi Influence Factor (MIF). Factors such as geomorphology, geology, land use/land cover, rainfall, lineament density, drainage density, elevation, slope, and soil were considered to accurately predict GWPZ. The AHP technique was used to construct a pairwise comparison matrix (PCM) and assign weights to each thematic layer, whereas the MIF method computes a recommended score for each layer based on the sum of the major and minor effect weights. The findings demonstrate that a significant portion of the study area falls into the "good" GWPZ (∼ 83% for both methods) category, indicating that the aquifer's storage is adequate. The output was validated by the Receiver operating curve (ROC) and groundwater prospects data. The ROC findings showed that the Area under curve (AUC) was 81% and 80.1% for AHP and MIF, respectively. This outcome signifies moderate to high precision indicating that the model could make accurate positive predictions. Analysis of pre-monsoon and post-monsoon water levels reveals spatial variations, with lower water levels indicating higher potential. Water levels in low-lying plains with high groundwater potential zones (GWPZ) are declining due to coastal erosion, sediment accumulation, limited infiltration, and increasing seawater intrusion. Continued groundwater abstraction may aggravate seawater intrusion despite favorable geological conditions. This study would be advantageous for coastal region decision-making involving water resource management and planning for sustainable development.

Groundwater Potential Zone Delineation Using Multi-criteria Decision-making Approach: A Case Study

Over-exploitation of groundwater from coastal aquifers causes seawater intrusion and depletion of freshwater resources. As 40 percent of the world’s population live within 100 km of the coast. This will increase the demand for potable water in coastal aquifers. Hence, it is essential to evaluate the sources of fresh-groundwater potential and productivity in coastal aquifers. Nowadays, integrated studies based on geographic-information systems play a major role in groundwater-exploration studies. Thus, the current study was carried out with the objective to delineate groundwater potential in the Nambiyar river basin in Tamil Nadu's southeast coastal area, where groundwater is in a critical condition. In order to improve groundwater recharge, it is very important to identify possible recharge areas. A novel work of the integration of remote sensing, geographic information system (GIS) and multi-criteria decision-making approaches of analytical hierarchical-process methodologies (AHP) was used in the present study. A total of 11 thematic layers, such as slope, curvature, soil, roughness, topographic-wetness index, drainage density, land use/land cover, geology, geomorphology, lineament density and rainfall, were generated for delineating groundwater potential zones. All the thematic maps are weighted using AHP based on the attributes of the classes and the potential capacity of their water supply. The demarked region of groundwater potential was validated by comparing pre-monsoon and post-monsoon groundwater levels. The groundwater potential zone map was classified into five categories: very high, high, moderate, low and very low. Areas with very high and very low potentials are delineated only in very limited areas. 64% of the regions are covered under the moderate-potential zones. The low-and high-groundwater potential zones are delineated at 22% and 14%, respectively. KEYWORDS: GIS, Recharge areas, Groundwater potential, Nambiyar river basin, AHP

Characterization of Groundwater Potential Zones from a Tropical River Basin, Southern Western Ghats, India

The increasing demands for groundwater resources and marked changes in climate over the years have imposed immense pressure on global groundwater resources. The present study has been undertaken to emphasize the expediency of remote sensing and geographic information system (GIS) to delineate the groundwater potential of a small tropical river basin of Kerala (India), viz., Thuthapuzha River Basin. Atotal of 10 geo-environmental thematic layers such as Geology, Geomorphology, Drainage density, Rainfall, Soil, Slope, Topographic Position Index, Groundwater level and Curvature were prepared and studied for groundwater potential zone demarcation. Weights assigned to each class in all the thematic maps are based on their characteristics and water potential capacity through Weighed overlay method (WoM). The groundwater potential zone map subsequently obtained was classified into five classes-very high, high, moderate, low and very low. The study reveals that about 63% of the river basin is covered under a moderate groundwater potential zone. The low and high groundwater potential zones are observed at 27% and 9%, respectively. The area under very high and very low potential zones is recorded only in very limited areas (>1%) in the basin. Keywords: Groundwater Potential Zone; Weighed Overlay Method (WoM); GIS; Thuthapuzha River; Kerala

Mapping Groundwater Potential Zones in the Habawnah Basin of Southern Saudi Arabia: An AHP- and GIS-based Approach

The excessive depletion of groundwater resources and significant climate change have exerted immense pressure on global groundwater reserves. Owing to the rising global demand for drinking water, as well as its use in agriculture and industry, there is an increasing need to evaluate the capacity and effectiveness of underground water reservoirs (aquifers). Recently, GIS has gained significant attention for groundwater exploration because of its ability to provide rapid and comprehensive information about resources for further development. This study aims to assess and map the groundwater potential of a large basin located in the southern region of Saudi Arabia. Techniques such as GIS and AHP were employed in this study. To perform the delineation for the groundwater potential zones (GWPZ), seven thematic layers were prepared and analyzed. These layers include geology, slope, land use, lineament densities, soil characteristics, drainage density, and rainfall. These variables were carefully considered and examined to identify and categorize areas based on their respective groundwater potentials. The assigned weights to each class in the thematic maps were determined using the well-known analytic hierarchy process (AHP) method. This methodology considered the characteristics of each class and their capacity to influence water potential. The results’ precision was verified by cross-referencing it with existing information about the area’s potential for groundwater. The resulting GWPZ map was classified into the following five categories: very low, low, moderate, high, and very high. The study revealed that approximately 42.56% of the basin is classified as having a high GWPZ. The low and moderate potential zones cover 36.12% and 19.55% of the area, respectively. Very low and very high potential zones were found only in a limited number of areas within the basin. This study holds global importance as it addresses the pressing challenge of depleting groundwater resources. With rising demands for drinking water, agriculture, and industry worldwide, the effective evaluation and management of underground water reservoirs are crucial. By utilizing GIS and AHP techniques, this study provides a valuable assessment and the mapping of groundwater potential in a large basin in southern Saudi Arabia. Its findings and methodology can serve as a model for other regions, supporting sustainable water resource management globally.

MAPPING GROUNDWATER POTENTIAL ZONES USING RELATIVE FREQUENCY RATIO, ANALYTIC HIERARCHY PROCESS AND THEIR HYBRID MODELS IN NZHELELE-MAKHADO AREA, SOUTH AFRICA

The water deficit in Nzhelele-Makhado area calls for an efficient assessment to delineate and map existing alternative water resources for future extraction. We are of a view that the identification of groundwater potential zones (GWPZ) in an area is as equally important as determining the most effective groundwater mapping models for the efficient production of reliable GWPZ maps. Consequently, relative frequency ratio (RF), with predictor value, and analytic hierarchy process (AHP) models, including two RF-AHP hybrid models (HM-A and HM-B) were applied and compared to evaluate their effectiveness and accuracy in groundwater potential mapping of Nzhelele-Makhado area. HM-A model is based on the ranks of classes of groundwater controlling factors that were computed by RF model and weights of controlling factors computed by AHP model. Meanwhile, for HM-B model it was vice versa. Eight groundwater controlling factors (slope, geomorphology, lithology, lineament density, soil, rainfall and land use land cover) were considered for this assessment. These were derived and extracted from conventional and remotely sensed datasets. The resultant GWPZ maps computed by the four models were classified into five categories: very low, low, moderate, high and very high groundwater potential zone. The RF, AHP, HM-A and HM-B has an area coverage of 13.62%, 21.50%, 14.56% and 19.62%, respectively, in very high potential zone. The area under curve (AUC) was used to assess the accuracy of the four models and evaluate the resultant maps using 37 geosites in the area. The RF, AHP, HM-A and HM-B show the AUC value of 72.47%, 60.55%, 71.96% and 49.85%, respectively. The models based on RF-derived ranks show better accuracies than models based on AHP-derived ranks. This suggest that the ranks have more influence in the performance of models than weights. The weights derived by AHP and RF models were generally consistent; thus, confirming that the ranks have more influence on the resultant maps. The maps generated from RF-derived ranks can therefore be used for further ground-based investigation of groundwater potential sources in the area.

Integration of hydrogeological data, GIS and AHP techniques applied to delineate groundwater potential zones in sandstone, limestone and shales rocks of the Damoh district, (MP) central India

The Damoh district, which is located in the central India and characterized by limestone, shales, and sandstone compact rock. The district has been facing groundwater development challenges and problems for several decades. To facilitate groundwater management, it is crucial to monitoring and planning based on geology, slope, relief, land use, geomorphology, and the types of the basaltic aquifer in the drought-groundwater deficit area. Moreover, the majority of farmers in the area are heavily dependent on groundwater for their crops. Therefore, delineation of groundwater potential zones (GPZ) is essential, which is defined based on various thematic layers, including geology, geomorphology, slope, aspect, drainage density, lineament density, topographic wetness index (TWI), topographic ruggedness index (TRI), and land use/land cover (LULC). The processing and analysis of this information were carried out using Geographic Information System (GIS) and Analytic Hierarchy Process (AHP) methods. The validity of the results was trained and tested using Receiver Operating Characteristic (ROC) curves, which showed training and testing accuracies of 0.713 and 0.701, respectively. The GPZ map was classified into five classes such as very high, high, moderate, low, and very low. The study revealed that approximately 45% of the area falls under the moderate GPZ, while only 30% of the region is classified as having a high GPZ. The area receives high rainfall but has very high surface runoff due to no proper developed soil and lack of water conservation structures. Every summer season show a declined groundwater level. In this context, results of study area are useful to maintain the groundwater under climate change and summer season.The GPZ map plays an important role in implementing artificial recharge structures (ARS), such as percolation ponds, tube wells, bore wells, cement nala bunds (CNBs), continuous contour trenching (CCTs), and others for development of ground level. This study is significant for developing sustainable groundwater management policies in semi-arid regions, that are experiencing climate change. Proper groundwater potential mapping and watershed development policies can help mitigate the effects of drought, climate change, and water scarcity, while preserving the ecosystem in the Limestone, Shales, and Sandstone compact rock region. The results of this study are essential for farmers, regional planners, policy-makers, climate change experts, and local governments, enabling them to understand the groundwater development possibilities in the study area.

Assessment of Groundwater Potential Zone using Multi-criteria Decision-making Technique: A Case Study in the South-western Part of Yadadri Bhuvanagiri District, Telangana, India

Abstract Groundwater which occurs beneath the earth’s surface is an important natural resource. The study area, part of Yadadri Bhuvanagiri district, Telangana, which is a part of Musi river basin, is a hard rock terrain covering an area of 1107 sq km, part of the eastern Dharwar craton (EDC) of the southern India peninsular shield. Exploration of groundwater in this terrain is difficult because groundwater is confined to weathered and fractured layers. The present study aims to delineate groundwater potential zones using the multi-criteria decision analysis (MCDA) technique. An integrated application of remote sensing and GIS is very effective in mapping features that provide information about groundwater potential zones using several thematic layers such as geology, soil, geomorphology, slope, lineament density, drainage density, rainfall, and land use/land cover maps. The groundwater potential zones of the study area are classified into five categories, namely very high, high, medium, low, and very low and they occupied an area of 116.8, 381.29, 345.15, 149.70, and 115.42 km2 respectively. The results were validated using discharge data from existing wells in the study area, and the majority of the high-productivity wells are located in very high and high groundwater potential zones. The groundwater potential zone mapping using this model will be a very useful improving the groundwater resources of the study area.

Groundwater quality enumeration and health risk in the extended part of Chhotanagpur granite gneiss complex of India.

The majority of people on the earth bank largely on groundwater to quench their thirst. In the era of rapid population growth, the over-exploitation of groundwater gives rise to water scarcity, and people find themselves in distress to manage safe drinking water. In this backdrop, the present study is carried out in the terrain of Pre-Cambrian igneous and high- to low-graded metamorphic rocks, to assess the groundwater potential zones (GWPZs) and evaluation of groundwater quality. The map of GWPZ is produced employing the multi-criteria decision-making model and geospatial technology. It unveils that around 29% area of the watershed enjoys good GWPZ, whereas around 43% area experiences low GWPZ. The overall accuracy of the simulated model is 92%. The water quality index indicates that 68% of water samples belong to excellent to good water quality. A significant proportion of water samples (24%) are found to be unsuitable for drinking, which may be due to groundwater contamination by the process of leaching of mineral-rich weathered rocks. The presence of fluoride (F-) beyond the maximum permissible limit (1.5mg L-1) of WHO is recorded among 18% samples of the watershed, where 24,963 souls including 3457 children aged between 0 and 6years lived and might have ingested F- through drinking water. Hence, the health risk of those people is quite high. Children are at a more non-carcinogenic health risk of F- than adults. The study also confirms no statistically significant difference (p ˃ 0.05) is observed between low and high GWPZ with respect to groundwater quality. The study recommends adopting a sustainable outlook to explore GWPZ, and an assessment of drinking water quality must be done before drinking.

Integrated GIS, Remote Sensing, and Electrical Resistivity Tomography Methods for the Delineation of Groundwater Potential Zones in Sangaw Sub-Basin, Sulaymaniyah, KRG-Iraq

In the Sangaw region, groundwater is the primary supply of water for drinking, residential purposes, livestock, and summer farming activities. Therefore, the main objective of this research is to delineate groundwater potential zones (GWPZs) in the Sangaw sub-basin, Sulaymaniyah, KRG-Iraq, by integrating geographic information system (GIS), remote sensing (RS), analytical hierarchy process (AHP), and electrical resistivity tomography (ERT) techniques. Seven different thematic layers, including geology, rainfall, slope, lineament density, land use/land cover, drainage density, and topographic position index, were chosen as the prediction factors. The analytical method of an analytical hierarchy process pair-wise matrix was used to evaluate the normalized weight of these thematic layers. All the layers and their corresponding classes were assigned ranks and weights based on their impact on groundwater potential. Using ArcGIS, these thematic maps were combined to precisely determine the groundwater potential map within the research area. Five different potential zones were generated for the resulting map, namely, very low (55.4 km2), low (90.4 km2), moderate (68.1 km2), high (100 km2), and very high (62.4 km2). The findings revealed that almost 43.2% of the study region is characterized by high to very high groundwater potential zones. In contrast, the very low to low groundwater potential covers around 38.7%, and the moderate groundwater potential occupies 18.1% of the study region. The final map was then validated using results from the two-dimensional inverse sections of eight electrical resistivity tomography profiles. The validation data confirmed that groundwater potential classes strongly overlap with the subsurface water-bearing or non-bearing lithology, and groundwater productivity zones in the given area. The novelty of this research lies in the application of electrical resistivity tomography validation to the groundwater potential mapping approach, which illustrates the robustness of the overall methodology for data-scarce areas. Furthermore, this is one of the very few groundwater potential studies in Iraq and the first in the Sangaw sub-basin, which can assist decision-makers with groundwater prospecting and management, and enable further exploration in the region.

Groundwater Potential Zone Mapping in the Ghaggar River Basin, North-West India, Using Integrated Remote Sensing and GIS Techniques

The immense dependence of the growing population on groundwater has resulted in depletion at a fast pace can be seen nowadays. Identifying a groundwater potential zone can be proved as an aid to provide insight to the decision-makers and local authorities for planning purposes. This study evaluated the delineation of groundwater potential zones using integrated remote sensing and GIS approach. Various thematic layers such as geology, geomorphology, lineament, slope, drainage, soil, land use/land cover, and rainfall were considered in this study as these have influence on the occurrence of groundwater and its cycle, and maps have been prepared in GIS domain. Afterward, appropriate weights were assigned to these layers based on multi-criteria decision analysis, i.e., Analytical Hierarchy Process (AHP). Groundwater potentiality has been delineated in different zones (low, moderate, high, and very high) in the study region based on weighted overlay analysis. The study reveals zones with different groundwater prospects viz. low (1.27%), moderate (15.65%), high (75.54%), and very high (7.29%). The ground survey data provided by CGWB (Central Ground Water Board) of nearly 100 wells/dug wells/borewells/piezometers have been used for validation purposes, showing comparable results with the groundwater prospects zones. It also confirms that the majority of these wells fall under very high or high groundwater potential zones. They were also found to be thereby indicating that there is the existence of a permeable reservoir with considerable water storage in the subsurface. One of the most important issues for users and governments is groundwater depletion. Planning for the available groundwater resource is made easier by identifying the potential for groundwater (low to high).

Spatial Prediction of Groundwater Withdrawal Potential Using Shallow, Hybrid, and Deep Learning Algorithms in the Toudgha Oasis, Southeast Morocco

Water availability is a key factor in territorial sustainable development. Moreover, groundwater constitutes the survival element of human life and ecosystems in arid oasis areas. Therefore, groundwater potential (GWP) identification represents a crucial step for its management and sustainable development. This study aimed to map the GWP using ten algorithms, i.e., shallow models comprising: multilayer perceptron, k-nearest neighbor, decision tree, and support vector machine algorithms; hybrid models comprising: voting, random forest, adaptive boosting, gradient boosting (GraB), and extreme gradient boosting; and the deep learning neural network. The GWP inventory map was prepared using 884 binary data, with “1” indicating a high GWP and “0” indicating an extremely low GWP. Twenty-three GWP-influencing factors have been classified into numerical data using the frequency ration method. Afterwards, they were selected based on their importance and multi-collinearity tests. The predicted GWP maps show that, on average, only 11% of the total area was predicted as a very high GWP zone and 17% and 51% were estimated as low and very low GWP zones, respectively. The performance analyses demonstrate that the applied algorithms have satisfied the validation standards for both training and validation tests with an average area under curve of 0.89 for the receiver operating characteristic. Furthermore, the models’ prioritization has selected the GraB model as the outperforming algorithm for GWP mapping. This study provides decision support tools for sustainable development in an oasis area.

Groundwater potential zone mapping using geographic information systems and multi-influencing factors: A case study of the Kohat District, Khyber Pakhtunkhwa

Groundwater is a vital component of life; without its identification, it is impossible to live. Therefore, identifying groundwater potential zones (GWPZs) is critical. For this purpose, the study area of the Kohat District was selected to identify GWPZs using the multi-influencing factors (MIF) approach. The Kohat area has a semi-arid to sub-humid subtropical climate and is classified as a sub-tropical, triple-season, semi-arid, sub-mountainous area. The geology, land use, soil, rainfall, lineament density, and drainage density are important parameters of ground water potential identification. The GWPZs were classified into five types: very poor, poor, good, high, and very high. We determined that 37.72% of the study area had high GWPZs, which were predominately in or near the northwest region of the study area, whereas 4.62% of the study area, in the southeast region, had very poor GWPZs. The water table data from the study varied due to different parameters used to identify the GWPZs. Our MIF results revealed that a large area of the Kohat District has good water potential. Still, due to topographic elevation changes, the groundwater potential has been limited in hilly areas. Our final results were compared with water level field data collected from different sources across the Kohat District.

Delineation of groundwater potential zone for sustainable water resources management using remote sensing-GIS and analytic hierarchy approach in the state of Jharkhand, India

Groundwater abstraction in many parts of India is highly unregulated which has caused a gradual decrease in groundwater levels over the years. Normally surface water storage structures or recharge zones are developed without knowing if all the groundwater is getting recharged. The issue becomes serious in the plateau region where most of the rainfall goes as surface runoff. Here an effort was made to identify the groundwater potential recharge zones of the entire Jharkhand state using Remote Sensing, GIS, and Analytic Hierarchy Approach techniques. Thematic layers which could contribute to the successful recharge of groundwater were prepared. The whole region was classified into four prospective groundwater potential zones: extremely low, low, moderate, and high. The results showed that approximately 3.28 and 77.34% of the total area falls under the High and average groundwater potential zones and the rest are under Low and Very low. Most of the high potential area is located in eight districts due to the alluvial plain region or a few mountains in that region namely Godda, Sahibganj, Pakur, Dumka, Purbi, Singhbhum, Saraikela-kharsawan and part of the Ranchi. The discharge data of 28 existing bore wells were used to endorse the groundwater potential zones. The further validation was made with an Area Under Curve (AUC) of 83%. According to the validation, the applied method produces a fairly dependable outcome for the state of Jharkhand.

Evaluation of rock mass permeability along a borehole by integrating the techniques of geological features and logistic regression: a case study in Taiwan

When the budget for in situ hydraulic tests is constrained, cost-effective approaches for determining the variations in hydraulic conductivity along a borehole remain enticing for helping design and planning of groundwater-related engineering systems. This study proposes a practical method with probabilistic outputs for fulfilling engineering concerns. First, 474 sets of hydrogeological investigation and hydraulic test data of fractured rock masses in most of the watersheds of mountainous areas of Taiwan were collected. Then, seven geological indices [rock quality design (RQD), depth index (DI), gouge content design (GCD), lithology permeability index (LPI), fracture density (FD), fracture width (FW), and groundwater velocity (GV)] significantly correlated with rock mass permeability were identified. Third, using logistic regression analysis, the seven indices were used as explanatory variables, and the hydraulic conductivity was utilized as an outcome variable (its threshold value is 1 × 10−6 m/s) for developing prediction models of high groundwater potential zones along a borehole. All indices passed the collinearity test, indicating no collinearity between the indices. To make the prediction models proposed more flexible in practical applications, a total of 127 combinations based on the combination selection of seven explanatory variables were explored to develop various prediction models. Through the validation of the Hosmer–Lemeshow test, Omnibus test, and Wald test for all developed models, only 77 models were statistically significant. The 77 models were evaluated by three measures of Nagelkerke R2, SR (success rate), and AUC (area under the curve) to further understand the prediction performance of each model. The results show that the accuracy of the prediction model is positively correlated with the number of geological indices used. When all seven geological indices are used, Nagelkerke R2, SR, and AUC can reach the best values, which are 0.83, 91.6%, and 0.976, respectively. In conclusion, the prediction model developed by combining geological indices with logistic regression analysis can provide a more efficient way of understanding the hydrogeological conditions of a borehole site.

Groundwater potential zone demarcation in the Khadir Island of Kachchh, Western India

In the present work, remote sensing, Geographic Information System (GIS), field investigation, and mapping methods/techniques were incorporated to demarcate the groundwater potential zones in the Khadir Island of the Kachchh region. Preliminary work consists of reconnaissance surveys and the preparation of various thematic maps of the region. The lithology (Khadir formation of Mesozoic period), slope, soil, land use and land cover (LULC), lineament density (Faults, fractures and linear valleys), drainage density, and geomorphology thematic maps were prepared using Advanced Land Observation Satellite - Phased Array Type L-band Synthetic Aperture Radar (ALOS PALSAR) data with 12.5 m spatial resolution, Sentinel-2 data (bands 8, 4, and 3), and ICAR- National Bureau of Soil Survey and Land Use Planning and Geological Survey of India (GSI) published maps. The Groundwater Potential Index (GWPI) was determined by integrating and computing the groundwater thematic maps. The groundwater potential map was further validated using the Cohen's Kappa statistic method. The GWPI determines a high groundwater potential zone in the study area, of which about 12.24% and 19.41% of the area are excellent and very good potential zones for groundwater extraction, respectively. The study shows that the Cohen's Kappa coefficient of 0.767, which falls under the “Good Strength of Agreement” validates the result and determines that the Western and Eastern parts of the study area have greater groundwater potential zones.

Identification of groundwater potential sites in the drought-prone area using geospatial techniques at Fafen-Jerer sub-basin, Ethiopia

ABSTRACT Analyzing the groundwater potential zone is a fundamental first step in investigating groundwater resources in arid and semi-arid regions. This study examined the groundwater potential zone of the Fafen-Jerer sub-basin by applying geographic information system (GIS) and remote sensing (RS). The study used ten influencing factors, including geology, geomorphology, slope, soil, lineament density, drainage density, land use, land cover, topographic wetness index, topographic roughness index, and rainfall, to identify potential sites. Based on their effect on groundwater recharge, the sub-class of each influencing factor was identified and evaluated. The weights were determined using the multi-criteria decision-making method’s analytical hierarchy process technique. At the conclusion of the investigation, the region was divided into four potential zones: low, moderate, high, and extremely high. The study region comprises 84% moderate potential zones, 14% high groundwater potential zones, and 2% low and extremely high potential zones. area under the curve (AUC) of the receiver operating characteristic (ROC) curve was used to evaluate the groundwater potential zone, and the findings show extremely good performance (AUC = 0.87). The study provides recommendations for stakeholders and water management professionals to develop a strategy for water resource management based on the conjunctive use of surface and groundwater.

Mapping the Groundwater Potential Zones in Kota Belud, Sabah and its surrounding areas by using the Geographical Information System (GIS) and Remote Sensing Techniques

The increasing demand for groundwater sources is due to many reasons; increasing in population, increasing in agricultural area, pollution, industrialization and urbanization. The declining supply of clean water every year worsen this situation. This study aims to map the groundwater potential zones in Kota Belud, Sabah and its surrounding by using the Geographical Information System (GIS) and remote sensing techniques. Five parameters were studied that influence groundwater potential in the study area. The parameters are derived from existing maps, remote sensing imagery, and associated databases. The parameters are; rainfall distribution, drainage density, lineament density, elevation and slope steepness. All of these parameters will be used to create a thematic map based on a given weighting value. Finally, all the thematic maps will be integrated to produce the final groundwater potential map of the study area. The groundwater potential map is classified into five categories which are very low, low, moderate, high and very high. This study shows that three major factors that significantly affecting the occurrence of groundwater in study area are rainfall distribution, elevation, and slope steepness, and almost half of the study area was a high groundwater potential zone.

Using Geospatial Techniques and Analytic Hierarchy Process to Map Groundwater Potential Zones.

This study is conducted in Luvuvhu River Catchment (LRC) of South Africa, which has numerous major agricultural farms that are located in the upper catchment, especially in Levubu Valley. The significant irrigation developments in upper catchment have resulted in a decrease in the yield of surface water resources to such an extent that these resources struggle to meet domestic and industrial demand. The aim of this study is to delineate groundwater potential zones (GWPZ) as a way of establishing alternative water resources to relieve the overly stressed surface water resources. Various datasets are processed to extract groundwater controlling factors. Map layers of controlling factors are assigned weights according to their relative importance to groundwater occurrence using analytic hierarchy process and then integrated based on weighted sum analysis to generate GWPZ map. Rainfall infiltration breakthrough (RIB) and area under curve (AUC) are used to validate the GWPZ map. GWPZ map shows that lower catchment has very high groundwater potential covering about 409 km2 . Nonetheless, about 50% of LRC spatially falls within high groundwater potential zone. Groundwater recharge, based on RIB for three boreholes, that is, A9N0007, A9N0008, and A9N0018 around Levubu Valley is estimated at 8.3, 15.4, and 16.2%, respectively. Boreholes A9N0018 and A9N0018 correspond to moderate to high groundwater potential zone, whereas A9N007 coincides with low to moderate zone. Considering the groundwater recharge estimates and associated potential zones, RIB results correspond well with GWPZ map. Also, an AUC, based on 26 boreholes, of 70.9% is achieved; thus, indicating a reliable model.

Mapping of Groundwater Potential Zone Using GIS and Remote Sensing of Shwan Sub-Basin, Kirkuk, NE Iraq

The groundwater is an intrinsic and vital capital for providing water supplies in rural and urban areas. Climate change poses a strong threat to the world; especially in Iraq is considering one of the arid and semi-arid regions. The climatic changes lead to an increase in the demand for groundwater, especially with low rainfall and an increase in the population. It is very important to model groundwater potential for the sub-basin. This paper aims to produce a map defining the potential groundwater zones of the Shwan sub-basin. By Geographic Information System and remote sensing data, the required data or six factors (geology, elevations, slope, drainage density, soil, and land uses/land covers) are available to be collected through weighted overlay for creating groundwater potential map. The result was five zones for groundwater potential from very low towards the eastern parts and also end of the western boundary to very high towards the western parts of the sub-basin. The geological formations of the sub-basin such as conglomerate, low elevations, low slope and low drainage density consider as high groundwater potential zones.

Application of RS and GIS to Capture the Interplay of Geological Units and Watershed Development Activities: Implications on Change in Groundwater Potential with Reference to Anjeni Micro-watershed

Abstract In the dryland areas watershed development is one of the major programs of the Government of India. Ever since its initiation (1981), large tracts of degraded lands are treated through this approach. Remote sensing (RS) is a tool that has been successfully applied to capture groundwater potentials in different regions and geological units. In this study RS & GIS tools are applied to correlate groundwater potentials with various geological controls and watershed development activities at Anjeni watershed,Udaipur district, Rajasthan, India. In the study reference periods taken are year 2013 (pre-project) and 2016 (post-project). A hydro-geomorphological approach integrating remote sensing applications,field investigations, geological and hydrological studies were undertaken to delineate and study the groundwater potential along with recharge dynamics before and after intervention situation. Thematic maps were prepared through linking the RS data with morphometric characteristics, topographic analysis, land use/cover assessment and groundwater conditions.Geographical Information System (GIS) was used to integrate all the contributing factors like lithology, geomorphology, LU/LC, lineaments, drainage, and slope with the help of weighted overlay analysis. Merging the characteristics of groundwater potential, hydro-geomorphology, geology, water harvesting structures, morphometric analysis, lineament density studies, and water balance elements provide an effective approach for the delineation of potential sites for groundwater. This integrated approach has successfully captured the changes that occurred in groundwater situation of the Anjeni watershed in form of poor to very high groundwater potential zones. It establishes the importance of application of RS-GIS in flagship development program of the watershed management.