Bangladesh - Causes, effects and prevention of Flooding
The capital city is Dhaka
The Himalayas are situated to the North of the country.
It is situated on an Arcuate Delta - very fertile lands.
80% of land is less than 1 metre above sea level.
In Summer 25% of land is submerged under sea and it can reach as high as 40%.
The river is rapidly changing as 1820 million tonnes of sediment being carried through Bangladesh.
Nation with a high drainage density.
It's an LEDC with an average income of $360, many are surviving on a dollar a day.
Population of 147 million, population density is high at 1019 people per km.
48% suffer from malnutrition and only 0.2% have computer access, 0.4% have a telephone and only 14% are literate.
Evaluation of Bangladesh flooding:
+ Flooding is essential as farming season is planned around the floods and rice requires large amounts of water (their main crop).
+ Leaves behind fertile silt - one of the most fertile countries in the world. In normal years the floods cover 1/3 of the land in shallow water.
+ June-September monsoon season replenishes underground water supplies, provides soils with nutrients and provides a breeding ground for fish (source of animal protein).
- Death through drowning, snakebites, electrocution from floating power cables and waterborne diseases e.g. cholera, diorrehea etc.
- Families torn apart - orphans
- Food and water shortages as the crops have been ruined and the water supply polluted.
- Destruction of communications leaving it almost impossible to deliver aid.
- Much soil erosion due to the silting up of the river channel reducing its capacity.
May 1995: 40,000 dead, resulted in famine.
September 1988: 2,400 dead, 25 million left homeless, 80% of the country under at least 1m of water, infrastructure ruined and they experienced the heaviest monsoon rains ever.
June 2004: $7 billion worth of damage, 1 in 3 workers off sick with waterborne diseases. 600 dead, 30 million left homeless, 20 million in need of food and 100,000 suffered from diorrehea
Management of Flooding in Bangladesh
+ Stops smaller floods by increasing the river's capacity.
- They can burst increasing the damage caused. They may trap water - becomes stale carrying waterborne diseases.
+ gets people away from the flood danger areas, reducing the death toll e.g. 1991- 150,000 died - 1998 only 1000 died.
- Not enough flood shelters and they've poor access.
+ This will allow people to evacuate safely and reach storm shelters.
- Not many people have access to communications (TV, phones, internet) so few will know about the flood risk.
+ It will decrease lag time, increase interception, less surface run-off and less soil erosion - it's a long-term, sustainable solution.
- This is more long-term as tress take years to grow.
+ allows flow to be controlled during flood periods and the stored water can be used during the dry season.
- They may end up storing necessary water which leads to drought.
