Modeling Culvert Failure and Community Accessibility Impacts During Hazards.

Culverts (or road-stream crossings) are prone to failure during extreme events such as flooding. However, culverts are considered small-scale infrastructure and have been understudied and overlooked. The impact of culvert failure could be far-reaching and is especially damaging in rural networks where there is less redundancy in the transport system when compared to a dense urban network. Culvert failure can block road infrastructure and disconnect community members from places of interest such as hospitals. Current work on culverts has focused on improving component level condition ratings. This work allows for prioritization at the component level; however, culvert failure should be modeled as a system event where multiple culverts may fail at one time. Community characteristics are also neglected from current work focusing only on culvert condition ratings. Spatial distributions of communities and places of interest must be integrated into risk analyses to holistically understand culvert impact. This paper introduces a new methodology for simulating culvert failure during hazard events. Particular attention is given toward measuring community impact and using publicly available data to ensure transferability. Additionally, infrastructure-induced disconnection is coupled with community characteristics to identify areas of concern and propose mitigation actions. Finally, culvert importance metrics are introduced to help identify critical culverts within the system. The method is illustrated on a case study network in Western Massachusetts.