The document discusses methods of flood control and river management. It describes various causes of flooding such as heavy rain, urbanization, dam collapse, monsoon rains, and deforestation. Common flood control techniques include building dams and pumping stations to control water levels, constructing barriers like levees and flood walls, altering river channels by straightening and widening them, and controlling land use near rivers. The document also provides examples of river management for the Mississippi River in the US, which uses an extensive levee system, and the Nile River in Egypt, which is controlled by the Aswan High Dam.