"The share of Americans living in counties and parishes that are at least partially protected by earthen and concrete levee systems increased to 62%, or more than 201 million people, in 2019, compared to 55% a decade earlier, according to Federal Emergency Management Agency statistics obtained by Levees.org, a New Orleans-based advocacy group.
However, the number of people actually living within the areas protected by levees in counties is likely much smaller. For instance, in 2018, the Army Corps of Engineers estimated that 11 million people -- 3% of the nation's population -- lived or worked behind the 2,200 levee systems it built or maintained, representing just over half of all levees nationwide. More than 1 million people of those people live in the New Orleans area.
Sandy Rosenthal, who founded Levees.org in 2005 after Hurricane Katrina to provide the public with information about how and why New Orleans area levees failed during the storm, said the new data again confirms that New Orleans is not alone in relying on levees for protection from hurricane storm surge flooding."