GWEN IFILL: Next: Even with the BP oil well sealed, environmental worries linger along the Gulf Coast. NewsHour correspondent Tom Bearden reports from Louisiana's wetlands.
TOM BEARDEN: When BP's Macondo well started spewing crude oil into the Gulf, a lot of people were afraid it would kill thousands of acres of marsh vegetation, accelerating coastal erosion.
Hundreds of miles of boom were deployed to try to keep that from happening. But Garret Graves says some of the oil got through, and wreaked havoc. He's the director of the Louisiana Governor's Office of Coastal Activities.
GARRET GRAVES, director, Louisiana Governor's Office of Coastal Activities: There is no question that the areas that have been oiled are dying. We have -- we have been out there. And some areas that were lightly oiled one time, you had some browning of the vegetation.
We believe the root systems are remaining intact. Repeated, even light oilings appear to have killed those plants and likely the root systems. The heavily oiled areas appear to be totally dead.
TOM BEARDEN: Aaron Viles is the campaign director for the Gulf Restoration Network, an environmental advocacy group.
AARON VILES, campaign director, Gulf Restoration Network: You can't really clean it up. You know, you can try to put some water in the system to flush out some of the oil, but, you know, getting in there to physically try to remove the oil will likely do more harm than good, because we will actually be driving oil into the root system.
TOM BEARDEN: The oil spill is just the latest insult to Louisiana's wetlands. They have actually been under siege since the great flood of 1927. That year, the Mississippi River flooded 27,000 square miles of land, killing 247 people in seven states.
The government ordered the Corps of Engineers to build higher, stronger levees and massive flood-diversion projects. The river was contained and navigation improved. But Louisiana's wetlands also started to die. Dr. Ralph Portier is an LSU scientist.
DR. RALPH PORTIER, professor, Louisiana State University: Well, where we are standing, a dramatic example of how this changed. Over my shoulder, this used to be a very valuable cow pasture. Dairy cattle were raised here in the 1970s. And, as you can see now, it's -- it's a coastal marsh.
TOM BEARDEN: He says channelizing the Mississippi prevented the river from depositing new silt and delivered less freshwater to the marshes. That allowed saltwater from the Gulf of Mexico to attack marsh grasses.
DR. RALPH PORTIER: It dissolves the marsh, and it also kills the freshwater root systems that are there, because they can't handle the salt.
TOM BEARDEN: Portier says, even before the spill, years of oil and gas industry operations also killed wetlands. For nearly 60 years, the companies drilled wells in the marshes and dredged canals so boats could reach them. That allowed even more saltwater to intrude.
Don Briggs says, when the canals were dredged, nobody realized what kind of damage they might cause. He's the president of the Louisiana Oil and Gas Association.
DON BRIGGS, president, Louisiana Oil and Gas Association: When you look at the pictures, it looks horrific, when you see all the different canals that were drilled and different fields where's there are lots of canals that are dug. And, today, that's not the mode of the industry. That's not what we do in the industry any longer, because we have technology where we can drill from one site. And we use old sites.
TOM BEARDEN: Regardless of the reasons, the consequences are enormous.
DR. RALPH PORTIER: Everything from this being the major flyway for migratory birds from the upper part of North America to the Gulf, to the major fisheries, this parish that we're in is one of three parishes or counties here in the United States that more seafood is harvested for domestic consumption here than anywhere else in the Lower 48.
TOM BEARDEN: Loss of wetlands and barrier islands also left Louisiana more vulnerable to the impact of hurricanes. Graves says the oil spill was a serious setback to the restoration work that was being done after Hurricane Katrina.
GARRET GRAVES: Because of the investments that the state had made in coastal restoration and ecosystem restoration, we were actually on track this year to have the lowest rate of land loss since the 1930s. And I think the oil spill has put that in jeopardy, and I think really beyond jeopardy.
I think the oil spill has prevented us from reaching that this year because of the additional land loss that will occur because of the oiled wetlands in South Louisiana.
TOM BEARDEN: A lot of people in Louisiana think the BP spill might provide a unique opportunity to focus Washington's attention on coastal erosion, and perhaps even provide a way to pay for some of the enormous cost of restoring those lost wetlands.
AARON VILES: There is a Clean Water Act fine that is going to be enormous, because it's assessed per barrel spilled. If that Clean Water Act violation is linked to criminal negligence, the amount paid per barrel goes up. So, we should be seeing billions of dollars penalizing BP under their Clean Water Act violations.
TOM BEARDEN: Viles wants to use the money to remove some of the levees in the Lower Mississippi Basin, and allow the river to resume its historic role of providing silt and freshwater.
AARON VILES: We need a lot more money. We need a lot larger projects. And we need to be doing it strategically and science-based to ensure we can turn this problem around and start building land, instead of losing land.
TOM BEARDEN: Portier says it's way past time the rest of the country woke up to what is happening.
DR. RALPH PORTIER: People have to realize that this is not just Louisiana's coastal zone; it's the United States' coastal zone. This habitat, we're losing anywhere between 25 to 30 square miles of coastline a year. There is no equivalent anywhere else in the United States where we're using the coast that fast.
TOM BEARDEN: Portier and a lot of his fellow Louisianians say it's time to stop talking about the problem and actually start doing something about it.