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News Archive: Louisiana Coast Threatened by Wetlands Loss

Brian Handwerk
for National Geographic News
February 9, 2005
 
Editor's Note, September 8, 2005: In February 2005, National
Geographic News reported on the ongoing loss of wetlands along
Louisiana's Gulf Coast. At the time, marine biologist Max
Schexnayder warned that the disappearance of the marshes made the
coastal region—a linchpin in the U.S. oil and gas
infrastructure—vulnerable to frequent flooding and severe
hurricane damage. Hurricane Katrina has since provided the tragic
coda to that forecast. National Geographic News is republishing
the article from our archives.


Louisiana's wetlands are being washed away—an area the size of a football field disappears every 35 minutes. Their erosion is more than just an environmental concern, as it exposes the U.S. oil, gas, and fishing industries to harmful flooding and shifting waterways.

"Down here when we speak of wetlands loss, it's actual, physical loss," said Mark Schexnayder, a marine biologist with the Louisiana State University Agricultural Extension and Research Center's Sea Grant Program. "You can't stand on [the land] anymore. It's gone."

Coastal communities, many protected by small levee systems, already feel the brunt. With fewer wetlands to mitigate storm surges, residents and businesses are experiencing increased flooding.

"With the rapidly depleting wetlands, people that have lived in southern Louisiana can tell that, over the last 30 years, large storms now come in faster, and the water rises faster, which gives less time to respond and less time to evacuate," said Denise Reed, a professor of geology and geophysics at the University of New Orleans.

"In the next few years it's going to get worse."

Louisiana is home to more than 40 percent of the U.S.'s salt marshlands. Economic interests, from fishing to oil and gas companies, are dependent on marshlands, making their loss not just a local issue but also a national one.

National Energy Infrastructure at Risk

The Louisiana coast is home to many rigs and pipelines, crucial infrastructure for the domestic oil and natural gas industries and for petroleum arriving by ship from foreign sources.

Wetlands act as a natural buffer protecting such industrial systems from hurricanes and other storms.

Though it did not directly hit the infrastructure area, Hurricane Ivan nonetheless caused extensive damage to infrastructure in 2004.

A more direct hit—resulting in lost oil and wrecked infrastructure—could cause major disruptions to U.S. energy sources.

"I hate to even think what would happen if a Category Five hurricane would hit directly anywhere near here," Schexnayder said. "We were very, very lucky with Ivan—and still had damage to offshore facilities. And some pipelines are still out of commission."

Energy-consuming Americans aren't the only ones with a stake in the future of wetlands.

Shrimping and fishing industries could also feel the pinch of wetland loss.

The shifting coastal landscape is treacherous for the New Orleans shipping industry. Channels are filling, jeopardizing operations at one of the nation's largest ports.

Schexnayder hopes to preserve what's left—a far easier task than trying to rebuild wetlands after they've disappeared.

"There's a lot left that we can preserve and keep from going south," he said. "Being close to the situation for 20 years and watching islands disappear before your eyes, you tend to get frustrated with the pace [of protection efforts]."

Part of Schexnayder's task is public awareness. "It's not always easy to make someone from central Louisiana realize that an investment in the coastal wetlands is an investment for the whole state," he said. "And that needs to be understood on a national level."

Fortunately, in this area scientists got assistance from "student argonauts."

Students Wade Into Wetland Preservation Efforts

The JASON Expedition (formerly JASON Project) is a middle school program designed to engage students in science and math by partnering them with real scientists. Organized annually by the JASON Foundation for Education, a nonprofit based in Needham, Massachusetts, the expedition is sponsored by the National Geographic Society.

Scientists and students, called argonauts, travel into the field, where they do research and use satellite broadcasts and Internet technology to bring their interactive exploits to classrooms around the world.

This year, from January 31 to February 6, a group of students donned their waders and went to work in Louisiana's wetlands—shoulder to shoulder with the scientists who study them.

"At school you work with science teachers, but here you work with the people you see on TV, the people who are actually out there coming up with the information that we learn in science books," said Rosalind Fennell, a ninth grader at the Potomac School in Washington, D.C.

"During our broadcast a student [via the Internet] asked us what they could do," she said. "Part of it is just being aware. That's one of the main points of JASON—to help others to become aware."

"I got to help everyone around the world realize that our wetlands are disappearing and we need to take action," added Colleen Harris, a ninth grader at Colleyville Heritage High School in Colleyville, Texas.

Many Causes, Limited Solutions

This year's JASON broadcasts helped students and educators worldwide understand what's happening to Louisiana's wetlands. Scientists blame a number of factors, rather than a single cause, for the wetlands' decline. Natural marsh subsidence, or soil compacting, is occurring, but other threats are of human origin.

Flood-control efforts along the length of the Mississippi River have hampered natural delta building by blocking the floods that once periodically delivered water and sediment to the area.

Other changes have restructured the existing wetlands.

"What we've done on the surface has really, really changed ... the marshes," Reed added. "We've dredged innumerable oil and gas locations, most of which have dredge-material levees next to them. Those are only 4 feet (1.2 meters) high, but [they constitute] a mountain in the Louisiana marshes, and they really stop natural tidal flows."

Deep shipping channels alter water salinity throughout the marshes and produce corresponding ecological shifts.

Nutria called Myocastor coypus—rodents imported from South America—have added to the destruction by devouring already weakened wetlands.

"It's not one thing that really caused these massive problems," the University of New Orleans's Reed explained. "It's lots of things added together."

While the causes are numerous, there is only one obvious solution—returning sediment to the Mississippi Delta. And a decade of spending—50 million U.S. dollars annually—has so far failed to keep pace with the problem.

"The solution to rebuilding the marshes has to involve rebuilding the substrate," Reed continued. "That has to involve returning sediment to the system, and the Mississippi River is the only natural way to do that."

Scientists and students alike hope that their efforts will make an impact.

"I'm afraid that when I go back ten years later to the places we went with JASON, those places might not be there," student Colleen Harris said from her Texas home. "Hopefully they will be there. Hopefully we'll be able to make a difference."

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