Landslide hazard, vulnerability, and risk assessment (HVRA), Mussoorie township, lesser himalaya, India

In the present study, landslide hazard, vulnerability and the risk assessment of the Himalayan township Mussoorie, located in the lower part of the Lesser Himalaya has been undertaken. The area famous for tourism constitutes > 7000 buildings with ~ 30,000 habitations. Four bivariate statistical approaches viz. Weight of evidence (WoE), Frequency ratio (FR), Yule Coefficient (YC), and Information Value (InV) were used for landslide hazard assessment, and all these approaches with 75%—80% success and predication rate are found to be acceptable for landslide hazard mapping. The analyses indicate that the Nagar Palika Parisad ward, Library ward, Happy valley ward and Bhadraj ward exhibit the maximum area falling under the high and very high landslide hazard zones, whereas Landaur ward, Jalkii ward and Indra Colony ward exhibit a greater part of the area in the low and very low hazard zones. On the basis of the six elements at risk present in the study area viz. settlement, crop land, water body, roads, barren and degraded land, and dense forest, the ~ 40% of the area is very high and high vulnerable, ~ 11% moderate, and ~ 49% is low and very low vulnerable. High and very high vulnerable zones are located in the west and central portion mainly because of higher habitation and more anthropogenic activities. Finally, risk map prepared intersecting hazard and vulnerability maps exhibits that Nagar Palika Parisad ward has the largest part (~ 41%) of the area with 37% buildings falling in the high and very high risk zones, whereas the Landour ward is the safest ward having ~ 83% area in the low and very low risk. Overall ~ 1604 buildings with habitation of ~ 8,000 persons in the township, are prone to high and very high landslide risk. The results of this study may be utilized for further development and planning in the area.