FloodsFloodsBy Dima VasetskyyBy Dima Vasetskyy

10-A grade10-A grade

Causes of floodsCauses of floods Weather events heavy rainfall and thunderstorms over a short period; prolonged, extensive rainfall; high tide combined with stormy conditions.

Poor maintenance faulty sewer networks; poor or insufficient drainage networks; inadequate maintenance of watercourses.

Development/planning issues inappropriate development in flood plains.

Types of floodsTypes of floods

Coastal floodingCoastal floodingRiver floodingRiver floodingFlash floodingFlash flooding

Groundwater floodingGroundwater floodingSewer floodingSewer flooding

Coastal floodingCoastal flooding River Flooding River FloodingHeavy storms or other extreme weather conditions combined with high tides can cause sea

levels to rise above normal, force sea water to the land and cause

coastal flooding. Proper flood defences need to be in place to safeguard life and property. The Environment Agency and SEPA

constantly monitor sea levels and release flood warnings when

required.

This type of flooding, where a river bursts or overtops its banks and floods the areas around it, is more common than coastal flooding in the UK. River flooding is generally caused by prolonged, extensive rain. Flooding can be worsened by melting snow. Flooding can also occur if the free flow of a river gets blocked by fallen trees, natural overgrowth or rubbish.

GrondwaterGrondwater flooding flooding sewer Flooding sewer FloodingGroundwater flooding can occur

when water levels underneath the ground rise above normal levels

approaching the surface. It is usually caused by prolonged

periods of rainfall. Groundwater flooding can last for weeks and

months.

Sewer flooding may result from a failure of the sewerage system.

It may also happen when the sewer system does not have

enough capacity to take water entering the system from heavy

rainfall or river or highway flooding.

EFFEcts of floodsEFFEcts of floodsThe primary effects of flooding include loss of life, damage to buildings and

other structures, including bridges, sewerage systems, roadways, and canals.

Floods also frequently damage power transmission and sometimes power generation, which then has knock-on effects caused by the loss of power.

This includes loss of drinking water treatment and water supply, which may result in loss of drinking water or severe water contamination. It may also cause the loss of sewage disposal facilities. Lack of clean water combined

with human sewage in the flood waters raises the risk of waterborne diseases, which can include typhoid, giardia, cryptosporidium, cholera and

many other diseases depending upon the location of the flood.Damage to roads and transport infrastructure may make it difficult to mobilise

aid to those affected or to provide emergency health treatment.Flood waters typically inundate farm land, making the land unworkable and

preventing crops from being planted or harvested, which can lead to shortages of food both for humans and farm animals. Entire harvests for a

country can be lost in extreme flood circumstances. Some tree species may not survive prolonged flooding of their root systems

The most dangerous floodsThe most dangerous floods

Floods in China in 1931 St. Felix's Flood in Netherlands in 1930 Hanoi and Red River Delta flood in

North Vietnam in 1970 Eastern Guatemala flood in 1949 Bangladesh monsoon rain 1972 St. Marcellus flood in Germany,

Denmark and Netherlands in 1362 Vargas mudslide in Venezuela in 1999

Thanks for your attentionThanks for your attention