In recent years, there has been a significant uptick in the number of major flooding events across the United States and the Globe. According to NOAA, in the United States, billion-dollar events per year have increased from approximately 3 in the 1980’s to approximately 13 in the 2010’s and, in the past 5-years, to over 20. The total cost of the 376 events between 1980 and 2023 was over $2,600 billion, of which, nearly 80% was storm related.
This session examines data characterizing contemporary and future storms. Analysis points to a need to expand the design storm concept recognizing that storms are becoming more frequent; more broadly distributed seasonally; flashier (i.e. excess rainfall in short time periods) and there are more instances of multi-day events contributing to extended duration, wide-area flooding.
In the session, precipitation events such as those experienced in Tennessee in 2010, North Carolina in 2016, New York City in 2021, Massachusetts in 2023, and California in 2023 and 2024 will be examined. Through the analysis, the session identifies how data can inform a design storm strategy that supports multi-dimensional risk assessment considering flooding, streambank erosion & bridge scour, infrastructure resiliency, habitat destruction, and/or socio-economic impact.
The session concludes by introducing a design storm methodology that considers the bellwether 100-yr storm; events of exceptional intensity; and multi-day, wide-area storms events. Lessons derived help further develop our members to serve in key roles addressing the top challenges of our time: climate resiliency, disaster recovery, infrastructure performance, and societal well-being.
1 PDH