Almost all of Bangladesh’s
rivers have their source outside
Bangladesh has three mighty rivers, the Ganges,
the Jamuna and the Meghna
that it cannot
drain into the
enough to take
Most floods follow heavy rain or melting snow,
frozen ground and already high river levels.
The floods in Bangladesh begin through a
combination of heavy monsoon rains flooding
the rivers and abnormally high tides in the
Bay of Bengal preventing floodwater from
running off the land and into the sea.
The deltas of the Ganges and Brahmaputra rivers in South
Asia flood on a seasonal basis. The flooding keeps the soil
fertile because the rivers deposit silt which forms fertile soil
each year. Partly because of the flooding, it is one of the most
densely populated areas of the world (900 people per km2).
Millions of people in Nepal, Northern India and Bangladesh
depend on the rivers and fertile soils for their livelihoods.
Tear Fund UK
Where does the flooding occur?
Identify specific regions that are worst hit.
80% of Bangladesh is
located on the delta.
The low level of the
delta land means that
large areas are prone to
flooding. 75% of
Bangladesh is at or
below just 10 metres in
Total rainfall within the Brahmaputra, Ganges – Meghna
catchment is very high and very seasonal. 75% of annual
rainfall occurs in the monsoon between June and September.
Annual rainfall total in Dhaka is almost 2000mm
Tropical cyclones from Bay of Bengal bring heavy rain and
storm waves in late summer
Bangladesh also suffers
melting snows from the
Human factors that cause
• Deforestation may be partly to blame, stripping the land bare of
the vital top soil which slows and drains water. This causes soil
erosion which reduces the ability of the land to absorb water.
• Irrigation for farming is a factor, because this causes river
channels to silt up, reducing their capacity to hold flood waters.
According to some experts, irrigation interferes with river
drainage into the sea.
• Climate experts also believe global warming is partly to blame,
by increasing monsoon rainfall and speeding up the melting of
• In built-up areas with a lot of concrete roads and houses, there
are fewer places for water to go and less soil for water to drain
into. Planners in cities prone to flooding have to develop ways of
channelling water to cope with potential floods.
Bangladesh - Fact File
• is one of the world's most densely populated
• has a population of 125m inhabitants
• is one of the poorest countries in the world with a
GNP of $200 per head
• has three of the world's most powerful rivers passing
through its country - The Ganges, the Meghna & the
• contains virtually no raw materials or rock
• experiences floods and tropical storms every year
The Physical Causes of the
• Most of the country consists of a huge flood plain and
delta . 70% of the total area is less than 1 metre
above sea level
• 10% of the land area is made up of Lakes and Rivers
• Snowmelt from the Himalayas takes place in late
spring & summer
• Bangladesh experiences heavy monsoon rains,
especially over the highlands
• Tropical storms bring heavy rains and coastal flooding
• The main cause was the above average & long period
of heavy rain which caused all 3 rivers to have their
peak flow at the same time!!!
The Human Causes of the
• Deforestation in Nepal and the Himalayas increases
run off and adds to deposition and flooding
• Urbanisation of the flood plain has increased
magnitude & frequency of floods
• the building of dams in India has increased the
problem of sedimentation in Bangladesh
• Global warming is blamed for sea level rise, increased
snow melt & increased rainfall in the region
• Poorly maintained embankments (levees) leak &
collapse in times of high discharge
The Effects of the 1998 Floods
• Over 57% of the land area was flooded
• Over 1300 people were killed
• 7 million homes were destroyed
• 25 million people were made homeless
• There was a serious shortage of drinking water & dry
• Diseases spread such as bronchitis and
• As the waters receded - it left fields of rotting
crops, wrecked roads and bridges and destroyed
• 2 million tonnes of rice was destroyed
• 1/2 million cattle and poultry were lost
floods occurred July to Sept Airport, roads and railways
July 2004 - 40% Dhaka was under
60% of country was flooded Rice crop destroyed along with
food supplies – vegetables
600 reporte deaths
Cash crops – jute and sugar
20 million homeless
100,000 in Dhaka suffered from
diarrhoea as floodlwaters left mud
35cm of rain fell in 1 day on 13th
Sept page 115
Death toll rose to 750
During the monsoon, between 30% and
50% of the entire country is flooded.
The flood waters:
• Replenish groundwater reserves
• Provide nutrient rich sediment for
• Provide fish
• Reduce the need for artificial
• Bangladesh GNP US$ 380 per capita
• Short term concern is always for health survival and
suffering of people affected.
• A heavy reliance is placed upon emergency aid – food,
drinking water medicines, plastic sheets, boats
• Assistance is provided from United Nations,
• Problem is distribution because so much of the
country is underwater.
• As flood water recedes it is easier to set up medical
treatment centres, distribute water purification
tablets and provide help with repairing homes and
restarting economic activities
In 1989 the government of Bangladesh began working with a number of
international agencies to produce a Flood Action Plan. This huge
scheme contained 26 action points which it was hoped would provide a
long term solution to the country's flooding problems.
Short Term Management
• Boats to rescue people
• Emergency supplies for food, water, tents and medicines
• Fodder for livestock
• Repair and rebuild houses, as well as services such as sewage etc
• Aid from other countries
Long Term Management
• Reduce Deforestation in Nepal & Himalayas
• Build 7 large dams in Bangladesh to store excess water $30-$40 million
and 40 yrs to complete
• Build 5000 flood shelters to accommodate all the population
• Build 350km of embankment - 7 metres high at a cost of $6 billion to
reduce flooding along the main river channels
• Create flood water storage areas
• Develop an effective Flood Warning Scheme
How have decision makers respond to the flooding?
The Flood Action Plan (FAP) was set up in 1990 supported by several wealthy
countries and the World Bank. Its aim was to reduce the impact of the
floods that occurred annually in Bangladesh.
The FAP’s objectives were to set up regional planning groups to study and
monitor local river processes, followed by hard engineering aproaches. This
involved the construction of 3,500km of coastal and river embankments to
protect the land and to protect from storm surges brought by cyclones.
The project included building seven large dams partly to stop water from
reaching the land and to provide up to 15 floodwater storage basins.
Millions of dollars of aid were poured into the engineering projects but the
scheme remains unfinished due to corruption and inadequate funding.
As a result the FAP is not considered to have been a complete success.
Over 3 million people have been killed by coastal flooding in the last 30 years.
The first findings of the FAP in 1995 stated that, while the flood protection
scheme was economically desirable for urban areas, it was not a good idea in
rural areas, which are dependent upon fishing and farming.
What issues are faced in implementing
strategies in countries like Bangladesh?
Whilst the embankments have been strengthened,
increased in height and extended in many places, the
FAP has come across several problems, such as:
• The Bangladeshi Government cannot afford the high maintenance costs of
• The embankments are at risk of erosion from the rivers
• River channelisation by FAP embankments has increased the risk of flood
damage for downstream areas
• An estimated 8 million people were forced to move due to the FAP. These
were people who relied on farming and fishing to support themselves.
A sustainable solution?
• People have suggested that
Bangladesh really needs a mixture of
strategies involving flood forecasting
and early warning schemes together
with more well stocked flood
• These projects would be cheaper
and more appropriate for farming
and fishing communities in rural
areas and would be more in keeping
with local knowledge, skills and
income levels and thus more
sustainable. They would also have
the advantage of being less likely to
damage the ecosystems.
Imagine you are working as a volunteer for an aid
agency such as Water Aid in Bangladesh during the
floods of 2004. Write a letter home describing the
situation in the floods in Bangladesh, its effects and
responses to it. Try to make your account as real as
possible so that the reader can imagine the
experience. Include photo images, witness accounts
and describe your own thoughts and feelings.
Use the following links to add detail to your
• Why Bangladesh floods are so bad
• India 'made floods worse'
• Bangladesh floods worsen
• Bangladesh praised for disaster planning