The First Street Foundation, a non-profit research center, just published its first nationwide community level flood resilience report, The 3rd National Risk Assessment: Infrastructure on the Brink, which details the flooding risk over a 30-year period for every locale in the contiguous U.S. The report analyzes the vulnerability of five key dimensions of community risk, one of which is critical infrastructure. It determined that 25 percent of all critical infrastructure in the U.S. are at risk of being taken offline today from potential flooding. “Our work aims to determine the amount of flooding that would render infrastructure either inoperable or inaccessible,” according to Dr. Jeremy Porter of First Street Foundation. “By applying research on depth thresholds and comparing them to flood data and probability metrics, we can determine roughly the extent of flooding that would cause a road to be impassable to cars, or a hospital to be shut down.” The findings were incorporated into First Street’s Flood Factor tool; First Street also offers to share publicly available data with state and local stakeholders to help them assess their current flooding risk.

Flooding is the most common and expensive disaster in the U.S., according to FEMA. The water and wastewater sector, particularly, is vulnerable to operational disruptions from rising water levels, as Hurricane Ida in August demonstrated. During the hurricane and its aftermath, infrastructure facilities experienced surging water levels in parts of the South and Northeast, which triggered service disruptions that lasted for weeks in some locations. At a very large drinking water facility in Pennsylvania, for example, surging floodwaters filled with mud and debris poured into the facility and disabled operations for nine days. At another water treatment facility in New Jersey, a recently completed $37 million flood wall kept the floodwater out and allowed the facility to stay operational during the hurricane and its aftermath. Ultimately, as the risk from flooding continues to grow due to the increasing frequency and intensity of extreme weather events, infrastructure operators should continuously re-assess their facilities’ risk hazards and plan mitigation and prevention measures to increase their operational resiliency going forward. Access the full report here and read a news article related to Hurricane Ida here.