Nuisance flooding duration across the United States

Low level flooding, often termed high-tide, sunny-day, recurrent, or nuisance flooding, has the potential to disrupt routine activities of coastal communities such as interrupting traffic patterns and decreasing visits to commercial businesses. In some locations, it is suggested that recurrent flooding may be cumulatively more expensive over time than losses resulting from one large, rare event. Furthermore, rising sea levels will continue to increase the frequency of nuisance flooding, in some locations at accelerated rates. While recent research has progressed our understanding of patterns and trends surrounding the frequency of nuisance flooding events, the duration of these events, lasting from minutes to multiple hours, will undoubtedly also drive the severity of local impacts.

This research evaluates regional differences in the duration of nuisance flood events across the United States. The analysis is built upon a recently derived suite of nationally consistent thresholds for minor, moderate, and major coastal flooding. Within this framework, the duration of minor, moderate, and major events are specified from tide gauge data. The processes driving long and short duration events are defined by assessing the relative contribution of tides, mean sea level, and non-tidal residuals to each event. The duration and drivers of minor flooding at each coastal location are then compared to those experienced by moderate and major coastal flooding events. Understanding the relationship between the frequency and duration of low level flooding will help to distinguish differences in potential impacts, now and into the future.