Bridging technical and social dimensions in critical infrastructure accessibility assessment: A case study from Chile

Assessing accessibility to critical infrastructure (CI), e.g., drinking water supply and transportation network, during extreme natural events is fundamental for improving the resilience of urban and rural systems. This study introduces a novel methodology to evaluate the criticality of road network links for accessing CI, integrating both technical assessments and societal preferences. A Critical Accessibility Index (CAI) was developed and applied to a case study in the Metropolitan Region of Chile, using a goal programming framework to quantify the relative importance of seven CI types as perceived by 750 survey respondents. Drinking water supply was assigned the highest weight (59.7%), followed by healthcare (15.9%) and electricity (8.5%), reflecting priorities during an earthquake scenario. The CAI was estimated under two scenarios: one assuming equal CI importance and another incorporating community preferences. Results showed that in scenario (a), 69.3% of links had very low criticality, while in scenario (b), this decreased to 47.5%, with a notable increase in medium and high criticality links. Spatial analysis underscored the heightened criticality of drinking water access, especially in rural areas with low redundancy. Policy implications emphasize the need for dual-focused investment planning that balances technical criticality with social priorities. This approach supports inclusive and robust disaster risk management, offering a replicable framework for diverse regional applications.