Risk Management of Rural Road Networks Exposed to Natural Hazards: Integrating Social Vulnerability and Critical Infrastructure Access in Decision Making

Abstract
Road networks play a crucial role in accessing, sourcing, and evacuating populations during extreme natural events. These issues are especially critical in rural settings, where redundancy of networks is uncommon and where the population may present significant social disparities. Traditional risk management systems have studied the risk of the road network from a physical perspective, where the probability of damage is estimated in terms of its fragility (vulnerability) and exposure given certain hazard intensity measures. However, the specialized literature increasingly suggests the development of more comprehensive risk management systems, where not only physical aspects associated with infrastructure are considered but also the social and economic characteristics of the beneficiary population. This study proposes a Vulnerability Access Index for road network decision-making that integrates social vulnerability of rural communities exposed to extreme natural events and their accessibility to nearby critical infrastructure. The proposed methodology considers three stages: Stage 1, Social Vulnerability Index based on socioeconomic variables, to which a principal component analysis is applied to identify the most determining dimensions of social vulnerability; Stage 2, Importance Index to evaluate access to critical infrastructure, and; Stage 3, Vulnerability Access Index, which is obtained as a combination of the indices estimated in the previous stages. A case study is presented in a highly exposed region to volcanic hazards in Chile. The proposed index identified links of the road network that require special attention as they provide access to highly vulnerable population and present critical access issues.
Description
Keywords
Social vulnerability, Critical infrastructure, Road network, Access index, Natural hazard
Citation