LANDSLIDE HAZARD ZONATION ALONG NATIONAL HIGHWAY BETWEEN AIZAWL CITY AND LENGPUI AIRPORT, MIZORAM, INDIA USING GEOSPATIAL TECHNIQUES

One of the most common victim of landslide is road transport network. This is inturn affects the economy and population. Due complex tectonic set up and unplanned developmental activities in Mizoram, the most common geoenvironmental hazard in the state is landslide. The present study investigates the Landslide Hazard Zones along the highway between Aizawl city and Lengpui airport of Mizoram. This highway is the most important road connecting Aizawl city and other parts of the country. The study utilized Remote Sensing and Geographic Information System (GIS) techniques. The road was buffered 50m on both side to delineate the study area. Important factors which induced landslide were identified and accordingly, five thematic layers viz., slope morphometry, geological structures like faults and lineaments, lithology, geomorphology and land use / land cover were generated. These thematic layers were ranked and weighted based on their relative importance in causing landslide. Each class within a thematic layer was assigned an ordinal rating from 1 to 10 as attribute information in the GIS environment. These attribute values were then multiplied by the corresponding rank values to yield the different zones of landslide hazard. Landslide inventory map is also considered while classifying the the different zones of landslide hazard. The resulting Landslide Hazard Zonation map classified the area into five relative hazard classes like very high, high, moderate, low, and very low. The final map generated will, therefore, be used by engineers and administrators for maintenance and monitoring of this highway to ensure smooth flow of transportation between the state capital and Lengpui airport, which the only airport in Mizoram. Remedial measures for landslide were also suggested at several landslide locations.