Transcript:
This summer marks 20 years since Hurricane Katrina devastated New Orleans. Since then, the city has built stronger levees and higher flood walls.
But parts of New Orleans are sinking, so the city will likely need to continue updating its flood defenses over time.
Simone Fiaschi was part of a Tulane University team that analyzed satellite data to study land movement in and around New Orleans from 2002 to 2020.
Fiaschi: “To better understand where the ground movements are happening, but also at what rates.”
They found that most of the city is stable. But several places are subsiding significantly – including some areas that provide critical flood protection.
For example, a wetland northeast of the city that absorbs water and helps buffer the city during storms is sinking by up to two inches each year.
Fiaschi: “If the rates continue as they are right now, in the near future, we are going to lose the wetland because that will become open water.”
And although Fiaschi says the city’s flood walls are still high enough to keep people safe, the ground below some of them is also sinking by about an inch per year. So over time …
Fiaschi: “For sure, that will impact the protection that the flood walls can bring to the city.”
So he says tracking the changes is critical, so the city can intervene and improve its flood defenses when needed.
Reporting credit: ChavoBart Digital Media