Abstract. In view of climate change driving extreme events such
as floods, assessing urban infrastructure resilience is critical for
disaster response and urban planning. We investigated how flooding in
Rio Grande do Sul affected road network connectivity and urban
resilience in terms of lack of redundancy to healthcare facilities. We
performed centrality analysis using the edge betweenness indicator to
identify urban arteries critical for connectivity at metropolitan and
intracity scales and compared alternative routes to assess healthcare
facilities resilience. Understanding how floods disrupt road
connectivity and mobility is critical for identifying vulnerable areas
and improving disaster response planning. The results revealed that just
71 km—or 2% of the total analysed network—accounted for 12% of
core-metropolitan connectivity prior to the floods. These
high-centrality urban arteries, including the BR-290 Freeway, were
disproportionately affected: they lost approximately 92% of their total
centrality after the flooding. Overall, the road network experienced a
59% reduction in betweenness centrality at the core metropolitan scale.
At the municipal level, impacts varied. For example, Canoas experienced
a 59% loss in intracity connectivity, while Nova Santa lost only 14%,
despite a larger flooded area (113 km2 versus 65 km2). Regarding the
analysis of urban resilience to access healthcare facilities, the
results revealed higher deficits in peripheral hospitals, such as
Hospital Restinga e Extremo Sul, indicating a lower resilience. These
results indicate the importance of multi-scale analyses to reveal
spatial disparities and inform disaster risk management. This study
provides actionable insights to support decision-makers in improving
emergency responses and strengthening infrastructure resilience to
future climate-related disasters.
https://doi.org/10.5281/zenodo.4059767