The Mississippi, called “America’s Greatest River,” rises in western Minnesota and flows south for 2,530 miles into the Gulf of Mexico. But after more than a century of abuse by humans, the Mississippi (pictured here from Baton Rouge) is in dire need of help. Due to an abundance of locks, dams and 1,678 miles of levees, the river utilizes only 10 percent of its original flood plain. The Audubon Society says this means the river now supplies barely any of the sediment needed to support its delta. Consequently, as much as 19 square miles of delta land disappear each year. Recent blows such as the Gulf oil spill have only worsened the situation. Fortunately, the Mississippi River has an abundance of conservation projects and initiatives dedicated to its care.