Use of hazard and vulnerability maps for landslide planning scenarios: a case study of the Nilgiris, India

Even small number of built-up areas experienced landslide problems; however, the loss could rise when the built-up areas develop in and on the unstable slopes. Landslide hazard information serves one of the many components in an integrated development planning study. A study on spatial vulnerability assessment is carried out for the part of Nilgiris district in the Western Ghats of India with the help of remote sensing and geographical information system to make use of landslide planning scenario. A spatial database is created for past landslide histories in the study area. The critical facilities, transportation and lifeline utilities, which include tourist spots, banks, ATMs, educational institutions, hospitals, bus stops, railway stations, that are potential threat under the very high to severe landslide hazard areas were identified. These are the elements at risk during landslides. From the study, it has been found that the eastern part of the study area is more prone to landslides. The past landslide inventories very clearly reveal that most of the landslides are triggered by the intense rainfall, human and cultural activities. Out of 36 utilities in the study area, about 65 % critical facilities and 36 % of transportation and lifeline utilities are vulnerable to severe landslide threat. The output of the present study can be used as first-hand information for the decision makers and planners and also helpful for the further developmental activities in the landslide-prone areas of the Nilgiris district of India.