Assessment of groundwater potential zones for urban development site suitability analysis in Srivaikundam region, Thoothukudi district, South India

To demarcate groundwater potential zones (GWPZ) for the Srivaikundam region in Thoothukudi district, Tamil Nadu, India, an effort was made in this study to locate the subsurface basin for groundwater storage and to identify the suitable destination for the urban development, agricultural, and drinking needs. This study using remote sensing and geographical information system (GIS) with analytical hierarchy process (AHP). According to their respective importance for groundwater occurrence, Saaty's scale was appropriately weighted to give the thematic layers and their attributes. The selected thematic maps were then merged using the weighted linear combination method to produce the final groundwater potential zone map after the layers' assigned weights and their features had been standardized using the Analytic Hierarchy Process (AHP) and eigenvector approach. Based on Saaty's 9-point scale, each criterion or factor was given the proper weight, and the weights were then normalized using the analytic hierarchy approach (AHP). To create the groundwater potential prediction map for the research area, the method was incorporated into the GIS environment. For the purpose of identifying potential urban residential development sites, the generated GWPZ is combined with eight different thematic layers. Groundwater conditions have been used to define GIS analysis criteria, and each information layer has been assigned an appropriate rank and weightage. Finally, groundwater recharge zones have been selected and classified into low, medium, and high based on cumulative weighted value. The moderate groundwater potential zone covers the majority of the land, with areas of very low 0.5 km2 (0.1%), low 112.3 km2 (17.7%), medium 428.7 km2 (67.6%), high 87.8 km2 (13.8%), and very high 5.1 km2 (0.8%) accordingly. Furthermore, higher groundwater yields are estimated in medium to good zones, indicating greater potentiality of groundwater sources.