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The Mississippi River flows over rapids and falls. It drops nearly 700 feet between its headwaters at Lake Itasca and Minneapolis and Saint Paul.
It keeps dropping until it reaches the Gulf of Mexico. The river also gets wider as it flows south. Its water level keeps changing, too. This makes it hard to keep the river safe for boats. It also makes it hard to keep its shores safe for people to live there. But over the years, engineers have built dams, levees, and locks. These things help control the mighty Mississippi.
