Landslide Hazard Zonation Mapping Using Geo Spatial Technology in Bodimettu Hills, Theni District, Tamil Nadu, India

Landslides are often destructive and periodically affect the Bodimettu district. The landslide events not only cause fatalities but also damage to road, buildings, vehicles, etc. and affect the society by disturbing the utility services and economic activities. Rainfall is one of the triggering mechanisms for the landslides and most of the landslide incidents correspond to peaks in rainfall which have occurred when the area was saturated with antecedent rainfall. Thematic maps were prepared on the various causative factors that is geo-system parameters like geology, lineaments/faults, geomorphology, land use/land cover, drainage system, slope, etc. High resolution Geo-eye satellite data, LANDSAT-TM and ASTER images have been used to generate thematic maps. The events have taken place mainly during North West (NW) monsoon during the months from October to December and only few slides have occurred during South West (SW) monsoon even if there is excess precipitation. The Possibility of landslide occurrences is due to improper drainage system, lithology, Intensive Rainfall, High slopes with no vegetation etc. The study also highlights the need for maintenance of landslide database and installation of more rain gauge stations to update and improve the Land Hazard Zonation (LHZ) maps to reduce the risk of landslide hazard faced by the human community.