Comprehensive Analysis of Riverine Flood Impact on Bridges: Iowa Case Study

Abstract

Floods often have a catastrophic impact on human life in terms of economic loss, infrastructure damage, and loss of life. Transportation network resilience is one of the critical aspects of supply lines for delivering goods and services during and after disaster events. Understanding vulnerable transportation segments is critical to addressing potential disruptions that may be caused by a flood event. In this study, we provide a comprehensive assessment of flood impacts on Iowa's transportation infrastructure, focusing on bridges, waterways, and traffic disruption. This research adopts a systematic framework, proceeding from a general overview at the state level to large-scale specifics. The initial segment outlines the statewide flood impact, progressively delving into individual bridges, waterways, and traffic ramifications. The research presented here analyzes the impact on inundated bridges across counties for varying flood intensities. Recognizing the disparity in county bridge counts, the inundated bridge ratio gains precedence alongside absolute counts. The southeast region of Iowa comes out as pivotal in flood scenarios, notably during 50-, 100-, and 500-year events. Marion, a moderately populated county in the southeast of Des Moines, stands out as a critical region due to its significant bridge inventory inundation in 100- and 500-year flood cases. The study also investigates bridge conditions, construction years, and their correlation with inundation risk to determine the vulnerability of bridges to flooding events and enhance our understanding of the potential effects of inundation on various bridge features. Furthermore, waterway bridge evaluations for different flood magnitudes and their impact on evacuation plans are explored. Transportation network vulnerability is assessed through closed-bridge effects on traffic. Average daily traffic values and detour lengths elucidate traffic disruption patterns across the state. These insights underscore the intricate interplay between floods and transportation, shedding light on bridge vulnerability, waterway evaluation, and traffic disruption. Overall, the presented research provides crucial information for flood mitigation strategies and resilience-enhancing measures in Iowa's transportation infrastructure.