LOUISIANA - Oil may no longer be flowing freely into the Gulf of Mexico, but remnants of the catastrophe will be around for years to come.
Many are especially concerned about the Louisiana wetlands, the place where the Mississippi River meets the Gulf of Mexico.
Sediment from the river settles into the system of wetlands that thrive on the delicate marriage of fresh and salt waters. They're a nursery for shrimp, oysters, and crabs. And they're in danger.
Dr. David White, a biologist at Loyola University in New Orleans, has been studying Louisiana's wetlands for decades. He offers a grim forecast.
"All of the grass and wetland plants, all of them that have been oiled, the surface leaves will all die," he said. "Those plants are going to die."
A History of Trouble
While oiled beaches are relatively easy to clean, White says wetlands are much more difficult. Their plants have shallow roots that grow just inches below the muddy soil. Just the weight of humans walking on the plants to clean them would crush their roots and suffocate them.
However, these wetlands were in trouble even before oil from the Deepwater Horizon leak started creeping into the area.
Darryl Malek-Wiley, a field organizer for the New Orleans chapter of the Sierra Club, keeps an aerial map of the wetlands. It's easy to see straight lines where the marsh has been dredged for oil and gas pipelines. These lines have allowed saltwater to intrude into freshwater, wreaking havoc on freshwater plants.
When oil was first discovered in the Gulf of Mexico in the 1930s, Malek-Wiley said coastal residents didn't understand the value or purpose of the marsh.
"It's an amazing web of life that we're just now getting a handle on," he said.
Weighing the Options
Now Louisiana's coastal parishes are weighing their cleanup options.
White prefers a technique called trimming. With this method, the grasses are essentially given a haircut while the wetlands are flooded to keep oil from collecting on their leaves when the water recedes.
Since oil started threatening Louisiana's coast, locals have been using the Mississippi River as a shield. Right now, the unhindered outflow of the river is keeping oil from washing too far into the marsh.
But it will be short lived. In autumn, the river level drops.
"You get low river water, you've got the potential then for tropical storms moving, potentially, oil into these interior lands of the delta. Not the peripheral, but the interior lands of the delta where most of the migratory birds stay over winter," White explained. "They (the birds) don't know oil from a hole in the ground."
A Bitter Dose of Reality
Another concern is just how long oil and toxic dispersements used to dissipate the oil will stay in the food chain. White fears it will be years - a sad dose of reality hitting the people who make a living on the waters.
"This is very valuable to me," said Stanley Encalade, a fisherman from the east bank of the Mississippi River. "At 50 years old, I don't want to go nowhere else and start nothing."
In 2005, Hurricane Katrina gobbled up 217 square miles of wetlands. Scientists are hopeful the oil won't destroy any more than that.
Many hope the disaster will draw attention to the work that was already underway to restore the coastal wetlands. People who live along the Gulf are ready for resolution.
"We got an old saying: you fish till you die," Encalade said. "I'm content with that, but I don't want to be flipping hamburgers till I die."
Originally aired on August 6, 2010.