The document discusses methods of flood control and river management. It describes various causes of flooding such as heavy rain, urbanization, dam collapse, tsunamis, snowmelt, monsoons, and global warming. Common flood control techniques include building dams and pumping stations, barriers like embankments and flood walls, altering river channels by straightening and widening them, and controlling land use near rivers. The Mississippi and Nile Rivers are discussed as examples, with details provided about the extensive levee system along the Mississippi and the Aswan High Dam on the Nile.