Wetlands Protection Has Long Received Inadequate Funding, Even Though they Absorb Some of the Destructive Power of a Hurricane

Flood control measures in southern Lousiana have led to large-scale damage to wetlands. An elaborate system of levees, dams, spillways, and pumps has allowed the presence of a major metropolis like New Orleans in an area that is below sea-level. But by straight-jacketing the Mississippi River, this system has also prevented the natural flooding on which the area’s wetlands and barrier islands depend for replenishing sediments. Without the river’s silt—channeled out into the Gulf of Mexico instead—the land must increasingly subside.

As a rule of thumb, every 2.5 miles of wetlands reduces the storm surge by 1 foot.

Some 1,900 square miles of coastal islands and marshland have vanished in Louisiana since the 1930s. Each year, an additional area of 25-35 square miles—roughly equivalent to Manhattan—are lost to the sea. Hurricanes Katrina and Rita submerged at least 118 square miles of marshland—an area almost twice the size of Washington, DC.

Related Links:

Mike Tidwell, “Goodbye, New Orleans. It’s Time We Stopped Pretending,” Orion Online.
Matthew Brown, “Coastal Losses Greater Than Thought,” The Times-Picayune, 15 February 2006.
Cornelia Dean and Andrew C. Revkin, “After Centuries of 'Controlling' Land, Gulf Learns Who's the Boss,” New York Times, August 30, 2005.