As the swollen Mississippi River rolls south, many residents living along the “Big Muddy” are scrambling to get out of its path. If the Army Corps of Engineers opens up the Morganza spillway in an attempt to save New Orleans and Baton Rouge, it will flood a 3 million acre flood plain and displace 2,500 residents of that area.

Opening the floodway would alleviate the pressure on levees further down the Mississippi that may not be able to withstand the bulging river. Experts predict a breach near Baton Rouge or New Orleans would result in catastrophic flooding worse than the disaster after Hurricane Katrina.

“It’s just sad on both ends,” said Capt. Adrian Slaughter of the Point Coupee Sheriff’s Office. “If it opens here, the other side gets the water. I mean, the decision that would have to be made, you know, we just hope everybody is OK.”

Adam Bo-dawn lives below the spillway in Butte La Rose, La.

“What they’re telling us,” he said, “is take whatever you want out cause it

probably won’t be there when you come back.”

In Warren County, Miss., Mary and Jack McGrew are packing up and moving out.

“Backwater levee’s that way,” Mary McGrew said, pointing. “And when the water comes in, we’re possibly going to have six feet of water in our house.”

Farther north, William Moore of Natchez, Miss., is taking a “wait-and-see approach.”

“You have to be optimistic,” he said. “You wouldn’t farm if you were not optimistic.”

His family has been farming 6,000 acres since 1880. In the worst-case scenario, the Moores could lose more than $2 million.

“The [Army Corps of Engineers] gives you projections,” Moore said. “They might be right. They might not be right.”

Moore pointed to pictures of the 1973 floods, which left his family’s entire property under water.

Further upriver, in Memphis, Tenn., health officials are still worrying about the muddy water still pooling in the city. The worst of the flooding may be over, but it has left behind a toxic brew of chemicals, fertilizers and sewage.

Samples tested for ABC News showed that levels of deadly E.coli, coliform and other bacteria were 2,000 times higher than any acceptable levels.