Using Advancements in Hydraulic Modeling to Gather Flood Impact Information for Decision Support Services

In early May 2010, historic flooding took place across much of Western and Middle Tennessee, where 10 to 20 inches of rain fell in less than 48 hours from near Memphis to Nashville. The epic flooding that resulted caused 24 deaths in Tennessee, more than a billion dollars in property damage, and catastrophic levels on many rivers, including the Cumberland River which flows through Nashville and aided in the inundation of the city.

After the flood, a Metropolitan Government of Nashville and Davidson County led initiative brought together representatives from the U.S. Army Corps of Engineers, the U.S. Geological Survey, and the National Weather Service to develop tools to mitigate the effects of future floods. One of the main outcomes was the development of inundation maps for various stages of the Cumberland River. Once these maps were produced with GIS software and satellite imagery, they were used to gather impact information at points away from the river gauges. The end result was a more robust list of impacts for areas that previously had little or no such information.

This presentation will outline the background and modeling that went into the inundation levels, and cover the process of gathering impacts from these maps. It will also demonstrate the accuracy of the inundation maps at all river levels by showing examples where photographs confirmed the depth and location of the water.