Mapping of potential groundwater recharge zones: a case study of Maputaland plain, South Africa

• Published in: Environmental earth sciences 2022-08, Vol.81 (16), Article 418
• Main Authors: Ponnusamy, Denisha, Rajmohan, N., Li, Peiyue, Thirumurugan, M., Chidambaram, S., Elumalai, Vetrimurugan
• Format: Article
• Language: English
• Subjects: Analytic hierarchy process; Baseline studies; Biogeosciences; Boolean; Boolean algebra; Coastal plains; Decision analysis; Decision making; Earth and Environmental Science; Earth Sciences; Eigenvectors; Environmental Science and Engineering; Geochemistry; Geographic information systems; Geographical information systems; Geology; Geomorphology; Groundwater; Groundwater availability; Groundwater data; Groundwater potential; Groundwater recharge; Groundwater resources; Hydrology/Water Resources; Land cover; Land use; Multiple criterion; Rainfall; Recent Advances in Environmental Sustainability; Slopes; Terrestrial Pollution; Thematic Issue; Water resources
• ISSN: 1866-6280; 1866-6299
• DOI: 10.1007/s12665-022-10540-4

The potential groundwater zones of the Maputaland coastal plain of Kwazulu-Natal is identified by comparing the analytic hierarchy process (AHP)—multi-criteria decision making (MCDM) technique and Boolean logical approach. The map of groundwater potential zones was prepared by assimilating the eight thematic layers, i.e., geology, geomorphology, lineament density, soils, slope, rainfall, and land use. Each thematic layer was assigned with a subjective relative weight under AHP-MCDM technique and Boolean logic and was overlaid in a GIS platform to identify the groundwater potential zones. The groundwater potential zones were delineated under two different GIS techniques to obtain confident results. Weights of thematic layers were allocated using AHP normalized Eigen vector methodology and weighted linear combination method was employed to find the groundwater potential index. Whereas in a Boolean approach, AND operator was applied to integrate thematic layers to delineate the groundwater potential zones. The delineated groundwater potential maps using AHP-MCDM technique indicates that 6.0% (310.5 km 2 ) from total area falls under very good; 67% (3467 km 2 ) good; 25% (1294 km 2 ) poor and 2% (103.5 km 2 ) under very poor, whereas in Boolean logic about 70% of the area (i.e., 3623 km 2 ) constitutes good and 30% (1552 km 2 ) of the areas constitutes poor groundwater potential zone. Further, the obtained results indicate that the geology, geomorphology, land use and land cover and slope played a vital role in groundwater recharge. This pioneer study in Maputaland coastal plain explores the baseline data of the potential groundwater zones. The results emanating from this study can be used in further understanding of the available groundwater resources and can be helpful in future to find suitable groundwater exploration sites in the area.