Flood control

Flood control (or flood mitigation, protection or alleviation) methods are used to reduce or prevent the detrimental effects of flood waters.^[1][2] Flooding can be caused by a mix of both natural processes, such as extreme weather upstream, and human changes to waterbodies and runoff. Flood control methods can be either of the structural type and of the non-structural type. Structural methods hold back floodwaters physically, while non-structural methods do not. Building hard infrastructure to prevent flooding, such as flood walls, is effective at managing flooding. However, best practice within landscape engineering is more and more to rely on soft infrastructure and natural systems, such as marshes and flood plains, for handling the increase in water.

To prevent or manage coastal flooding, coastal management practices have to handle natural processes like tides but also sea level rise due to climate change. Flood control is an important part of climate change adaptation and climate resilience.^[3]

Flood control is part of environmental engineering. It involves the management of flood water movement, such as redirecting flood run-off through the use of floodwalls and flood gates, rather than trying to prevent floods altogether. It also involves the management of people, through measures such as evacuation and flood proofing properties. The prevention and mitigation of flooding can be studied on three levels: on individual properties, small communities, and whole towns or cities.