The worst region for flash floods in the continental United States is likely the Southwest, according to a recent analysis of flash floods by The University of Alabama.
Using hydrologic data, along with socio-economic information, researchers at the UA Center for Complex Hydrosystems, led by center director Dr. Hamid Moradkhani, mapped the hotspots for flash floods.
They found the most severe effects from flash floods occur in a string of counties along the U.S.-Mexico border from Texas to California, including areas much further north in New Mexico, Arizona and even Nevada, according to the study published in Scientific Reports.
Many counties in Southwest states are not well equipped to prevent or recover from damages caused by flash floods even though the region has less frequent flash floods than other areas of the country, particularly the Southeast.
Overall, the poor socio-economic indicators in the Southern half of the U.S. affects the region’s response to flash floods events, the study found.
The Southeast states, particularly the Deep South, are hotspots for frequent and longer duration flash floods alongside poor socio-economic status, which reveals the region suffers from lack of infrastructure and sufficient resources to respond to more frequent flash flood events.
“Flash floods are among the costliest and most disastrous natural hazards worldwide because of their rapid onset that limits effective emergency response and management,” said Moradkhani. “Understanding the socioeconomic status of a region helps determine the underlying vulnerabilities, which will, in turn, be useful for discerning the risks and potential losses.”
Along with Moradkhani, the Alton N. Scott Chair Professor of Civil and Environmental Engineering, the paper is co-authored by two former doctoral students of Moradkhani’s, Dr. Sepideh Khajehei and Dr. Ali Ahmadalipour, who was also a post-doctoral researcher at UA, along with Dr. Wanyun Shao, UA assistant professor of geography.