Louisiana's coast is disappearing at the rate of about a football field an hour. Since the 1930s, the Gulf of Mexico has swallowed up an area the size of Delaware.
You can see the water encroaching in Delacroix in St. Bernard Parish, less than an hour southeast of New Orleans. Here, a narrow crescent of land known locally as the "end of the world" is where the road abruptly comes to a dead end; in the distance, you see the tops of now-submerged trees.
"It's hard to imagine if the coast continues to erode and enormous amounts of money are not invested in protecting it, that New Orleans could survive," says historian John Barry.
Barry is known for his book Rising Tide, about the 1927 Mississippi River flood. Most recently, he was vice president of the Southeast Louisiana Flood Protection Authority-East and pushed a lawsuit alleging that oil and gas companies destroyed land that once served as a buffer protecting New Orleans from hurricanes.
Related Stories From NPR
The Disappearing Coast