Exploitation of groundwater and frequent failure of monsoons has produced rapid water table depletion in present days. Rainwater is discharged as surface runoff without replenishing the groundwater table. Identification of potential zones for groundwater recharge has become an important event to replenish the groundwater resources. The recharge potential is governed by various features of surface, subsurface and hydrometeorological parameters. Remote sensing technique is found to be very effective tool for the integration of various features of these factors. In this work, an attempt has been made to identify groundwater recharge potential zones in Namakkal district of Tamilnadu state, India. Weighted index overlay analysis (WIOA) was carried out in this study using the software ArcGIS by intergrating the thematic layers of soil, geology, geomorphology, lineament, land use/ land cover, rainfall, groundwater level and slope. The groundwater potentials were delineated as Very Good, Good, Moderate to Good, Moderate and Poor zones. Good category of groundwater recharge potential zones constitutes 62.21 % in the study area. GIS based output results were validated with the water level data of Public Works Department (PWD).

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This study characterized the Owu drainage basin in southwestern Nigeria using geospatial approach with the objectives of examining the morphometry in relations to flood vulnerability of people in the region. Data used were the topographic maps and satellite imageries of the region. The data were analysed by both hydrological and geographical information techniques for basin delineation, stream ordering and digital elevation modelling. Results showed that the drainage basin is characterized by about 429 stream segments, and mean bifurcation ratio of about 1.9, and that about 23% of the entire basin area is susceptible to severe flooding. The study concluded that livelihoods and people in the flood vulnerable areas are endangered, and recommends preparedness for potential flood hazards in the area.