Katrina offers lesson on wetlands protection

Wetlands could have protected New Orleans, experts say, if so many acres hadn't been destroyed by years of alterations to the Mississippi River.

Published September 5, 2005

For years, experts have warned that New Orleans was doomed to drown.

Louisiana has lost more than 1-million acres of wetlands at the mouth of the Mississippi River. Scientists estimated that every 24 minutes another acre sank beneath the waves.

All those swampy acres could have protected New Orleans from inundation by Hurricane Katrina's record 29-foot storm surge. They used to function "like a sponge, absorbing rain and wind," said Craig E. Colten, a geography professor from Louisiana State University and author of Unnatural Metropolis: Wrestling New Orleans from Nature.

But now they're gone.

What happened to New Orleans should serve as a warning to other hurricane-prone states about the value of wetlands, experts say.


Using satellite imagery, the St. Petersburg Times found that Florida has lost 84,000 acres of wetlands to urban development over the past 15 years.

Unlike Florida, Louisiana's wetlands weren't replaced by subdivisions and strip malls. They were wiped out by alterations to the river itself. Since the 1800s the U.S. Army Corps of Engineers has been molding the Mississippi to fit mankind's needs, and ignoring the effect on the environment.

The corps dredged channels that turned the Mississippi into a backbone of the nation's economy and New Orleans into a bustling port city, a hub for the oil and gas industry and agriculture.

And thanks to the corps' work raising levees to hold back the river and Lake Ponchartrain, tourists visiting the Big Easy didn't worry about getting their shoes wet. But scientists now believe those alterations are responsible for as much as half the erosion of the state's coastal wetlands.

When Hurricane Betsy hit in 1965, "we had hundreds of square miles of more wetlands to protect New Orleans," said Marc Levitan, director of Louisiana State University's Hurricane Center. "The city is much more exposed, because those coastal wetlands are all gone."

Before the alterations, millions of tons of sediment flowing south in the Mississippi River would have replenished the wetlands and barrier islands in the delta on a regular basis.

"The levees on either side of the river meant increased water flow, so that what had been the tons and tons of sediment deposited as flood plain silt was being sent farther into the Gulf," Colton said.

The corps was not alone in killing wetlands that thrived on fresh water thundering down the river.

"Oil and gas interests dig canals wherever they like through the marshes" in order to lay pipelines from their offshore oil and gas rigs, said Carl A. Brasseaux, director of the Center for Louisiana Studies at the University of Louisiana at Lafayette.

"These canals led to saltwater intrusion that killed the (freshwater) marsh grasses, Brasseaux said.

That Louisiana's coastal wetlands have been disappearing has been known since the 1950s. The only solution, the experts agreed, was to rebuild the marshes, although they differed on how.

Since the 1980s Louisiana officials have asked Congress for money to do the work, but Congress was unwilling to spend much on a program where there were so many disagreements on solutions.

Then, in 1998, Hurricane Georges came within a hair of slamming into New Orleans. The near-miss scared everyone in Louisiana into agreeing to work together. They drew up a plan for restoration, but it had a $14-billion price tag. That's higher even than the anticipated cost of restoring the Everglades, which corps officials have called the largest environmental restoration project in history.

Congress and the Bush Administration balked.

Last year, after Hurricane Ivan gave Louisiana another scare, Congress again failed to act.

"What is it going to take for Congress and the president to realize this is not just another project?" gubernatorial aide Sidney Coffee told the New Orleans Times-Picayune last year. "Would we have had to get hit by the big one? Who wants to wait for that? Surely it shouldn't have to take loss of life, does it?"

A sophisticated lobbying effort, backed by such sponsors as Shell Oil and the makers of Tabasco, tried labeling the delta "America's Wetland" to drum up nationwide support. Finally, in July, the House passed a bill to provide $700-million to get started. It was awaiting Senate action when Katrina hit.

Now advocates argue that to protect New Orleans from the next hurricane, the $14-billion restoration should be part of the federal aid package Congress will pass to help storm recovery. And the old timeline for restoration - extending the work out 30 years - must shrink into a few years, they said.

"No one, the corps, the state, the oil and gas community, the environmental community, the parishes, treated this with sufficient urgency," said Scott Faber, a spokesman for the activist group Environmental Defense. "Now there's agreement that it is the most important component of protecting New Orleans from the next storm."

-- Times staff writer Robert Jenkins and researcher Angie Drobnic Holan contributed to this report, which contains information from Scientific American, the Times-Picayune and the Shreveport Times.