Humans have been trying to control floods for thousands of years. However, some flooding, particularly along the great river valleys (e.g. Nile) were the reason agricultural activities flourished and civilization developed
There is a balance between the regular flooding of river areas and catastrophic flooding
Dams and reservoirs are designed to aid in flood protection and control. They do this by controlling water levels and allowing water to flow as needed, but to protect lower elevations by storing water behind the dam wall.
River defenses -- Levees, bunds, reservoirs and weirs (low head dam) are all used to…