bangladesh

General Information on Bangladesh

Bangladesh is a LEDC country, or more specifically, a sovereign state located in South Asia. It is surrounded by India on all sides except for a small border with Myanmar to the far southeast and the Bay of Bengal to the south. There are three main rivers in Bangladesh are called Ganges (or Padma), Brahmaputra (or jamming), and the Meghna river. Economically speaking, it’s GDP is 111.9 billion USD per capita. Generally speaking, the landform contains virtually no raw materials or rock. It is one of the most flood prone areas in the world. 

---

Factors of Flooding (Natural)

Geological

• Low lying land: Bangladesh is a very low lying land with most of the nation’s acreage being flat. The land form is alluvial, therefore it is prone to severe flooding and cyclones coming in from the bay of Bengal. In addition, with 25% of the entire country only 1 meter (and lower) above sea level, the sea water can easily infiltrate into the land, creating surface runoff during floods.  
• Floodplains and river deltas: Since it is basically a delta for the convergence of the two major rivers, the Ganges and Brahmaputra, Bangladesh receives major amounts of water passing through. The maps shown here also display the varying land height of Bangladesh, around 70% of the its land area being low-lying, and 80% of it as a floodplain. Therefore, the flood prone ares range more around the center of Bangladesh where the rivers are located.
• Additional Information: The fertile flatlands of Bangladesh are surrounded by drainages located at the himalayas in the Northern area of the country, whilst only a small portion of Bangladesh feature hilly uplands. Furthermore, 10% of the land area is made up of lakes and rivers.

Factors of Flooding (Human Causes)

• Deforestation: There is major deforestation in the Headwater areas of the Bangladesh due to the rapid increase of population in Nepal and Tibet. The trees are cleared for fuel and grazing land for farmland owners.  This eventually leads to less evapotranspiration (which is the process in which water evaporates from land to atmosphere), more surface runoff, water flowing downstream at a higher velocity and faster soil erosion. Deforestation also lead to the reduction of interception rates, resulting in a shorter lag time and higher peak discharges.
• Urbanization: The urbanization of Bangladesh (again, due to increase of population), increases the magnitude and frequency of floods. Because it is an LEDC country, the poor levees Bangladesh builds often breach (leak or collapse) in times of high discharge. The increase of population in Bangladesh also results in the sinking of wells, which lowers the water table, subsequently caving in (or subsiding) the land, making the region even more prone to flooding. Because of the rapid population growth in Bangladesh, and since it is one of the most densely populated countries in the world, floodplain areas were moved, making 80% of Bangladesh a floodplain.
• Breaching of embankments: The breaching and cutting of embankments is mainly what aggravates flooding (seen from the research of recent floods in Bangladesh.
• Global Warming: Global warming is also said to be a factor that increased sea level and melted snow in the region. This also threatened the suburbans to become prone to flooding. 

Meteorological 

The climate and annual torrential rains result in the rivers exceeding their capacity and flooding in the coastal areas. Cyclones (violent storms) also often hit Bangladesh due to the country’s location near the warm seas just at the tropic of cancer. When there is heavy rain above the average rainfall, the three main rivers of Bangladesh might have a peak flow at the same time, causing major floods. 

Moist winds blow from the sea, bringing heavy monsoon rains from May to September, and consequently, the monsoon rainfall swells all the riverbeds, creating more surface runoff which eventually leads of flooding. In addition, during hot weathers ranging from 30-40º in the spring and summer, snow from the Himalayas increase flood risks by created melted snow, which enters the rivers at their source. 

Recent floods in Bangladesh (short term effects)

1988
The flooding in 1988 were mainly river floods caused by heavy rainfall throughout a wide area of the Ganges and Brahamputra river catchments. This was a major disaster than flooded 57% of bangladesh. Over 1 million people lost their homes as a result of the flood whilst 240 villages were submerged. 5000 people were killed and millions were left homeless with severe shortages of food and drinking water. Many diseases spread, crops were lost, and after all the river water was drained out only wrecked roads and bridges were left behind. 

1998 
In September, one of the most devastating floods in world history occurred in Bangladesh. 300,000 houses, 9700km of road, 2700km of embankment, 700,000 hectares of crop land have all been either heavily damaged or completely destroyed. 2/3rds of the country was submerged underwater with 1000 deaths and 31 million people left homeless. This was caused by the unusually high monsoon rains, and also the accumulation of the melted water from the himalayas that year. Many trees were also cut down which resulted in major surface runoff.

2004
Numerous floods occurred in Bangladesh this year. One in April destroyed 80% of the rice crop in many areas of Bangladesh. Another in July knocked out many household food stocks and sources of nutrition. Torrential downpours in September led to localized flooding again, with the flood water lasting up to three months in certain areas. 39 of 64 districts, 30 million people were affected directly.  This lasted over 1 month with a total death toll of 747 people, the flood leaving 7 million people homeless. This was mostly caused by, again, the heavy monsoon rains in Bangladesh and it’s neighboring countries, which resulted in the three major rivers of Bangladesh to have a peak flow at the same time. There was a shortage of food, shelter and drinkable water. Many schools, high-rise buildings, and homes were completely wiped out. Crops and cattle were also demolished to the point where citizens who are victims of the flooding lost everything. 

2007
The flood in 2007 was caused by excessive rainfall in the catchment areas of Nepal, Bhutan and Northern India. There were abnormal monsoon patterns, combined with the rapid increase of snow melt from the Himalayas. This affected 13.3 million people — more than half of Bangladesh. Caused a total of 1100 deaths, 90% of them being children, and displaced 400,000 people. There were 1.1 million houses damaged or destroyed. Lack of drinkable water and edible food led to 162,000 cases of diarrhea. More than 2.2 million acres of cropland was heavily damaged. 

Long term effects of Flooding in Bangladesh

The worst floods in Bangladesh since 1954 have a major long term effect on the current country, affecting 30 million people whilst the damage is still spreading, forcing the government to appeal for international aid. 

Social

Moreover, referring to the health issues present in the country, the government had to activate its medical budget to aid those severely injured and ill. Psychologically speaking, floods can also traumatize victims and their families for long periods of time. The loss of loved ones have great impacts on people, which may stain as a scar for the rest of their lives.

Economics 

The persistent negative impact of flooding in Bangladesh (nearly annually) is partially responsible for the negative long term effects economically in terms of having to provide more financial support for the citizens who are victims to floods. The flood led to a serious economic burden for Bangladesh. It created a 20% decrease in production and export industries due to the cut transportation routes such as railways, roads and the main port. 

Environmental

Deposition of silt on the top of levies increases their size and worsens the following subsequent floods. Flooding may also cause long term chemical damage to the land with all the dirt carried out during the flood, which possibly changes the biodiversity (the variety of life) of Bangladesh. Damage to infrastructure also causes many long-term impacts. These may exist as disruptions to supplies of clean water, wastewater treatment, electricity loss, transport, communication, education and health care.