Assessing Post‐Earthquake Emergency Healthcare Accessibility Considering Damage to Hospital Buildings and Transportation Infrastructure

This article presents a framework for performing a regional assessment of the accessibility of emergency healthcare facilities after a major earthquake. Accessibility is assessed by applying the enhanced two‐step floating catchment area method to a regional road network, implemented in ArcGIS. Damage state estimates for hospital buildings with emergency departments and bridges on the road network are used to estimate a reduction in hospital capacity and identify inaccessible links. We demonstrate the use of the framework through a case study of the Metro Vancouver, BC region under M9 Cascadia Subduction Zone earthquake scenarios and compare accessibility for four conditions: (1) baseline analysis before an earthquake, (2) considering hospital damage, (3) considering bridge damage, and (4) considering both hospital and bridge damage after an earthquake. Results show that hospital damage contributes the most to accessibility reduction due to a reduced ratio of emergency healthcare capacity to the population. By including bridge damage, the method allows identification of populations that become isolated after an earthquake due to loss of road connectivity in heavily damaged areas. We further demonstrate how the method may inform regional retrofit strategies. Outputs of the article highlight the importance of examining interdependent systems when performing regional seismic risk assessment and provide a framework to assist in infrastructure management decision‐making and emergency planning initiatives.