Effect of disaster debris, floodwater pooling duration, and bridge damage on immediate post-tsunami connectivity

This study establishes a general methodology to account for the effects of the amount of disaster debris generated, debris dispersal, the duration floodwater pooling for events like tsunamis, and damage to infrastructure on initial and time evolution of connectivity between critical facilities and key locations within a community such as evacuation zones and shelters. The proposed methodology is applied to Seaside, OR, for cascading seismic and tsunami hazards corresponding to seven return periods ranging from 250 to 10,000 years. The post-event connectivity is assessed for the first 72 h. The results provide insights on immediate post-event connectivity, its evolution with time as floodwaters recede and as the debris is cleared, and the relative effect of debris, floodwater pooling, and infrastructure damage on connectivity. For example, the level of disconnection caused by debris and flooding in Seaside is not always directly proportional to the return period (magnitude) of the seismictsunami event. Results show that bridge damage further exacerbates the lack of connectivity due to debris and floodwater pooling, highlighting that multi-hazard and multi-infrastructure analyses are necessary to understand connectivity for disasters.

Automated summary

This study establishes a general methodology for evaluating connectivity between critical facilities and key locations within a community, taking into account factors such as debris, flooding, and infrastructure damage. It reveals that the level of disconnection caused by debris and flooding is not always directly proportional to the return period of seismic-tsunami events.