Delineating the coastal vulnerability using Coastal Hazard Wheel: A study of West Bengal coast, India

Abstract

The present study was carried out to deliver an overview of the hazard profile and identify the hazard hotspots of the West Bengal coast. Indian coasts are under threat and vulnerable due to multiple stresses like sea-level rise, erosion, frequent extreme events, saltwater encroachment, and human intervention The newly developed Coastal Hazard Wheel (CHW) methodology explores the vulnerability scenario of any eco-system disruption associated with the gradual inundation; saltwater intrusion, erosion, and flooding of any coastal zone either at a local or regional scale. This study examines coastal vulnerability factors and their assessment of 185 km coast of West Bengal, India, using both CHW data and data of the primary survey. The result shows that the entire coast is high to very highly vulnerable in gradual inundation, saltwater intrusion, erosion, and coastal flooding. Islands of Sundarban and main lands of East Midnapur district facing the coast directly experienced by wave action are always prone to very high vulnerability. On the other hand, areas that are protected from open fetch of the ocean are less vulnerable to coastal hazards. Combined five hazard profiles (ecosystem disruption, gradual inundation, saltwater intrusion, erosion, and flooding) explore that coastal flooding and saltwater intrusion are in most vulnerable indicating a severe effect on the entire coast. Sea level rise induced gradual inundation can damage major parts of the coast. Erosion produces a very high to moderate impact (63%–37%).