Regional land use planning can be started in Kerala to reduce the risk of landslides: GSI Geology director

"A regional land use planning can be started immediately in Kerala with the available macro-scale landslide geo database to reduce the risk to a great extent," says Dr. Saibal Ghosh, Director, Geohazard Research and Management Centre, Geological Survey of India, in an e-mail interview to The Hindu as the State continued to face the increasing threat of disasters induced by landslide events. It is also important to note that, the conventional landslide susceptibility maps can only model the zone of initiation or source areas of any future landslide, and this is a systemic limitation of any landslide susceptibility model; however, like other areas, and in Kerala too, many damages have been noticed because of linear debris flows, where relatively stable slopes in the landslide runout and/ or accumulation zone, located much away from the source areas also become severely hazardous/ fatal, and thus need to be modeled too to comprehend the complete hazard scenario in an area, which is not only difficult but also is very challenging too. That is why, in mesoscale landslide susceptibility mapping, GSI is also attempting debris flow runout impact model outputs in the landslide susceptibility model to make it more inclusive, appropriate, and useful at that larger scale. In each district of the State, all the critical sectors for mesoscale landslide susceptibility and hazard mapping, and critical landslides for site-specific remediation need to be identified for planning and prioritising landslide remediation, mitigation, and management work To take up comprehensive landslide mitigation and management, some pilot districts in the State are to be identified first; and a comprehensive mitigation strategy for those districts be planned and implemented by taking into account all the available scientific data/ information; if new data is to be generated, the same may be prioritized for use; arrangement for exclusive funding arrangement for such mitigation tasks be made beforehand in a DPR mode; execution of mitigation work also needs to be monitored closely by an expert group.