The Mississippi River Delta Basin is not in serious trouble nor was it ever. Sometime in the course of human history, people began thinking that they were special as a species. The creation myth came into being that the world was created for man, and the world is ours to conquer. Well I hate to burst everyone's bubble, but the planet Earth does not belong to us. We are simply passengers along for the ride with the numerous other creatures that live here.
Because of the myth that the world is ours, we systematically began the process where we have attempted to control nature. You can find no better example of this attitude than the United States Army Corps of Engineers. They are charged with flood and erosion control in this country. Isn't it ironic that a branch of the military was given this job?
Getting back to the Mississippi River, flooding is a normal geologic process. When surface runoff increases during heavy or prolonged precipitation, or snow melt, the excess water is will enter a river system, and the river will overflow its banks. This water will saturate the relatively flat areas adjacent to the river channel, depositing sediment. Lining most rivers you will find a system of wetlands acting as buffers or sponges absorbing this water.
Check out a map of the United States sometime, and you will see that almost every major city is located near water. This of course was no accident. Before trains and truck and planes, waterways were the chief method by which goods and people moved. People were drawn to floodplains because of their rich fertile soils (which ironically are a result of the periodic flooding) and the ease of building on flat land.
When floods began occurring, instead of heeding the warning, we began building flood control devices such as levees and dams. While dams could hold back floods and let the water slowly leave, they also disrupted fish migrations and starved wetlands downstream. Levees have had to be built higher and higher. Not because of increased precipitation, but because we are systematically paving over the land, resulting in less infiltration of water and more surface runoff.
So to summarize, the Mississippi River Delta Basin is not in serious trouble nor was it ever. It flooded long before man walked the Earth and will continue to do so long after we are gone. It is we, and our arrogant attitude that are in trouble. Perhaps someday we will learn to live with nature instead of constantly battling it.