Waves on the coast of England, Hartlepool.
Source: Floodsite, HR Wallingford
Natural hazards for floods are:
- severe storm
- heavy rainfall
- sudden melting of snow or ice
By abundant rainfall or large amounts of snow, the water in a river or reach more dangerous heights. Storms can make the sea surge and make the waves ride high. A flood hazard does not always cause a flood. Perhaps the storm does not reach the coast. Perhaps the dunes can defend the land against the water.
Man-made hazards are:
- breach of a dam, dike or dune
- failure of a sluice, lock, weir
- listorm surge barriers not closing (or closing too late)
A man-made hazard will mostly lead to disaster only when it takes place under severe weather conditions. A sea lock that doesn’t close may not cause that much trouble at low tide, but it may at high tide or in a storm. A storm surge barrier that doesn’t close when it is tested on a sunny doesn’t cause problems, but if it doesn’t close in a severe storm surge it does.
Here you can see a presentation on natural hazards.
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