It's not nice (or smart) to fool Mother Nature

Dikes and levees built across the Mississippi River in the United States have prevented the annual flooding of the river delta, denying it access to fresh alluvial soils, and resulting in 1,900 square miles of coastal marshes and tidal wetlands being lost to subsidence and erosion. A coalition of environmental groups, scientists, the state of Louisiana, and the Army Corps of Engineers have envisioned a US$14 billion plan to save the delta and the coastal wetlands.