People watch a nine-barge tugboat make it's way through the Mississippi River when WaterShed Partners and Mississippi Makeover Project conduct a boat tour along Spring Lake and lower Pool 2, just ...

Richard Carlson, Hanska, MN, carries a 68-pound Bighead Asian Carp down to a paddleboat in Rosemount before a tour of Pool 2 on the Mississippi River June 13, 2012.

The map is based on a U.S. Geological Survey database of the direction water is flowing at every point on Earth. ... the Amazon River is more than 400 miles longer than the Mississippi River alone.

The vast Mississippi River—the second longest river in North America—swirls through a number of U.S. states and has been swelling in recent weeks. That may continue, experts say.