Impacts on people and society
Flooding can cause physical injury, illness and loss of life. Deep, fast flowing or rapidly rising flood waters can be particularly dangerous. For example, even shallow water flowing at 2 metres per second (m/sec) can knock children and many adults off their feet. Vehicles can be moved by flowing water of only 1 foot (300mm) depth. The risks increase if the floodwater is carrying debris. Some of these impacts may be immediate, the most significant being drowning or physical injury due to being swept away by floods.
Floodwater contaminated by sewage or other pollutants (e.g. chemicals stored in garages or commercial properties) is also likely to cause illnesses, either directly as a result of contact with the polluted floodwater or indirectly, as a result of sediments left behind. Those most likely to be at risk are people living in a single-storey bungalow or below ground in a basement, those outdoors, on foot or in a vehicle, or people staying in a tent or caravan.
As well as the immediate dangers, the impact on people and communities as a result of the stress and trauma of being flooded, or even of being under the threat of flooding, can be immense. Long-term impacts can arise due to chronic illnesses and the stress associated with being flooded and the lengthy recovery process.
The ability of people to respond and recover from a flood can vary. Vulnerable people, such as the elderly, people with a disability or those who have a long-term illness, are typically less able to cope with floods than others. Some people may have difficulty replacing household items damaged in a flood and may lack the financial means to recover and maintain acceptable living conditions after a flood.
Floods can cause impacts on communities as well as individuals through the temporary, but sometimes prolonged, loss of community services or infrastructure, such as schools, health services, community centres or amenities.