Decision support tools for prioritizing the hydraulic vulnerability of existing New York State coastal bridges due to the impact of climate change projections

With the reality of climate change now broadly accepted by scientific organizations and governments, bridge owners are considering how climate change projections may affect the safety of their bridges. Existing bridges were designed based on historic, or observed, climate conditions and not future climate change projections. The average age of U.S. bridges is 43 years, and it is possible that many of these bridges will still be in service in the latter half of the century. Projected increases in sea level may have strong implications for coastal bridge design, inspection, maintenance and risk assessment activities.;The first objective of this study was to develop a set of criteria to readily prioritize the hydraulic vulnerability of U.S. coastal bridges, in light of climate change projections, to serve as a decision support tool for bridge owners. The National Bridge Inventory database was the source from which the prioritization criteria were developed. This tool can assist owners in determining which bridges are likely to be the most vulnerable to climate change projections. These bridges can then be given the highest priority towards a more thorough risk assessment.;The second objective was to determine whether sea level rise projections would negatively impact a bridge's hydraulic vulnerability. Using the criteria developed, a negative impact was defined as an increase in priority from the historic to the projected climate condition. The New York State coastal area was chosen as the case study because of the region's sensitivity to changes in sea level. Nine (9) case study bridges were selected, and a projected sea level rise of 55 inches (1.4 m) was used for the hydraulic and scour analysis. It was determined that sea level rise projections would have a negative impact on the hydraulic vulnerability of New York State coastal bridges since four of the nine case studies increased in priority from the historic to the projected climate condition. Based on the research findings, revisions to national and state standards were recommended to incorporate sea level rise projections with regard to hydraulic studies, design and risk assessment.