Groundwater depletion is one of the most critical concerns for users and policymakers. Identifying groundwater potential (low to high) helps properly plan the available groundwater resource. This study has used the possibilities of a geographical information system (GIS), remote sensing and, of course, field data to delineate the groundwater potential zones in the Chennai River Basin (CRB). Thematic layers generated for eleven controlling factors, such as geology, water level, drainage, soil, lineament, rainfall, land use, slope, aspect, geomorphology, and depth to bedrock, were brought into the GIS environment. Then, appropriate weightage was given to each layer using a multi-criteria decision-making technique, namely, the analytic hierarchical process (AHP). A groundwater potential map is generated using weighted overlay analysis, with the following five classes: very poor, poor, moderate, good, and very good. The results were comparable to the actual specific yield data from the field and accuracy was 78.43%. Thus, AHP-aided GIS–RS mapping is a useful tool in groundwater prospecting in this region of the world.
