Landslide Risk in Hong Kong under Extreme Storms

Abstract

Landslides are a major hazard in Hong Kong which can lead to loss of life, injury to people, or economic losses. This paper assesses the landslide risk in western part of Hong Kong Island under extreme rainstorms of 29%, 44%, 65% and 85% of the 24-h probable maximum precipitation. The number of buildings affected and the total population inside the buildings have been identified. The vulnerability factor was evaluated as a function of travel angle and time of landslide occurrence. It was observed that the vulnerability factors increase as the travel angle increases for all the PMP levels. At 85% and 65% PMP, the occurrence of landslides and the risk they pose on buildings are much higher than those at 44% and 29% PMP. The lowest potential loss of life is observed in schools, hospitals, community centres and government buildings. The findings from this work suggest that the time of occurrence of landslides can significantly affect the distribution of potential loss of life in each building.