Dams
- essentially designed to help in flood protection and control
- most dams have flood-control reservations where the level of a reservoir has to be maintained below a certain elevation before it rains to allow a certain amount of space in which floodwaters can fill.
- Dry dams are dams which solely aim to control floods without any conservation storage
Water-Gate
- an immediate response which can be deployed quickly
- it self-deploys using the weight of water to hold it back
Diversion canals
- redirects excess water to purpose-built canals or floodways which diverts the water to temporary holding ponds or other bodies of water where there is a lower risk or impact to flooding
- Examples of flood control channels include the Red River Floodway that protects the City of Winnipeg(Canada) and the Manggahan Floodway that protects the City of Manila (Philippines)
Self-closing flood barrier
- a flood defense system designed to protect people and property from inland waterway floods caused by heavy rainfall, gales or rapid melting snow
- It can be built to shield residential properties and communities
- It is ready to deploy whenever and can be installed in any length, using the rising flood water to deploy
River defenses
- levees, bunds (embankment to hold back water), reservoirs, and weirs are used to prevent rivers from bursting their banks.
- When these defenses fail, emergency measures such as sandbags, hydrosacks or portable inflatable tubes are used.
- A weir, also known as a low head dam, is most often used to create millponds (the pool that is created by a milldam and provides the head of water that powers a water mill)
Coastal defences
- sea walls, beach nourishment, and barrier islands.
- Tide gates are used in conjunction with dikes and culverts. Tide gates close during incoming tides to prevent water from moving upland and open during outgoing tides to let the water drain out. The opening and closing of the gates is determined by the water level difference on either side of the gate. They can be placed at the mouth of streams or small rivers, where an estuary (where the tide meets the stream) begins or where tributary streams, or drainage ditches connect to sloughs (swamps).
Asia
- In India, Bangladesh and China, flood diversion areas are rural areas that are deliberately flooded in emergencies in order to protect cities
- Deforestation is viewed as a potential cause of flooding
- With natural forest cover, the flood duration should decrease. Reducing the rate of deforestation should improve incidents and mitigate the severity of floods
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