After Hurricane Katrina, the Army Corps of Engineers embarked on a $14 billion network of levees and floodwalls to protect greater New Orleans. The upgrades created what seemed to be an invincible safeguard against flooding.
Now, just 11 months after the completion of the project, the federal agency says the system will stop providing adequate protection in as little as four years. The statement from the Army Corps of Engineers cites rising sea levels and sinking levees as causes for concern.
The Army Corps is beginning to assess repair work, including raising hundreds of miles of levees and floodwalls. The repairs could cost hundreds of millions of dollars, with about 75% paid by federal taxpayers.
The system was built over a decade, concluding in May 2018. It is projected to no longer provide adequate risk protection as early as 2023, which illustrates the rapidly changing sea levels and local erosion that has wiped out protective barrier islands and marshlands in southeastern Louisiana.
The levees are losing height as they sink into the naturally soft Louisiana soil, but sinking is exacerbated by rising sea levels. Studies in recent years have warned about New Orleans’ vulnerability to sea-level rise.
The National Academy of Sciences projected that New Orleans could be among the cities hardest hit by rising sea levels.