Drought. Sea level rise. Dredging for cargo ships. Those are just some of the complex factors blamed for an inland flow of salt water from the Gulf of Mexico into the Mississippi River. Salty water was a problem for months for low-population communities at Louisiana's southeastern tip. Fears that the salt water would reach the heavily populated New Orleans area have abated for now. But people in rural Plaquemines Parish say too little was done to help them. Meanwhile, New Orleans-area officials say long-rage plans are needed for the return of the salt water threat.