Causes Of Flooding Flashcards
Five human factors that increase flooding?
- urbanisation: large areas of impermeable Tarmac so increased surface run off, gutters/drains
- flood management: dam fail
- agriculture: overgrazing less infiltration, overgrazing ploughing increased soil erosion
- climate change: increase rainfall/storms
- deforestation: reduced interception/ soil loose washed into river raise river bed smaller capacity
5 physical factors that increase flooding
- steep slopes
- high drainage density(lots of streams): drain quickly
- circular drainage: all points of basin similar distance so arrive in short time
- impermeable ground: increased surface runoff-clay, frozen, baked
- sparse vegetation or deciduous trees: decrease infiltration/no leaves
When does flooding occur
Discharge of river high and spills over its banks onto floodplain
What’s a major cause of flooding?
Prolonged rainfall- soil becomes saturated, increase surface runoff
Heavy rainfall- rapid surface runoff
Melting snow ice
5 social impacts of flooding?
- killed
- contaminated floodwater, lack of clean drinking water
- disease
- possessions damaged
- homeless
5 economic impacts of flooding?
- businesses shut down, premises inundated, power supplies affected
- rescue work and repairs costly
- unemployment levels rise due to closed down businesses
- public transport, roads destroyed
- crops destroyed, price of food increases
2 bad environmental impacts of flooding?
- floodwater contaminated, pollute rivers
- river banks eroded
2 good environmental impacts of flooding?
- flood plain more fertile
- wetlands created
Absolute/relative economic impact?
Absolute economic impact higher in richer countries- higher value buildings
Relative economic impact higher in poorer countries- crops building worth less but effect economy more and less money to recover
Social impact higher in poorer countries
