1
WMO/GWP Associated Programme on Flood Management
BANGLADESH: FLOOD MANAGEMENT
A.N.H. Akhtar Hossain
1
Abstract. Information is provided about the approach and long-year experience on flood
management in that country, with strategies that have seen continuous change after a number of
disastrous floods. Of interest is in particular the introduction of an integrated approach for flood
management, which has been reflected in recent plans for flood and water management
1. Location
Bangladesh is situated in the south Asian sub-continent. Because of its unique geographical
location and topography, it is one of the most flood-prone countries in the world. Approximately 20
to 25% of Bangladesh’s territory is inundated during the monsoon season. Such flooding provides
fertile agricultural land and the floodplains in the country are densely populated and intensely
utilized. On the other hand, at least 50 to 70% of the country’s territory is exposed to intermittent
extreme flooding that has far-reaching negative impacts on the national economy. Flood
management in Bangladesh is, therefore, perceived as an indispensable component of poverty
reduction initiatives.
2. Nature of floods
The country has a unique hydrological regime. It has 230 rivers, of which 57 are international,
Bangladesh in most cases being the lower riparian country. Of the three large transboundary river
systems (Ganges, Brahmaputra and Meghna), only 7% of their huge catchment areas lies in
Bangladesh. The major rivers have a length of 500 to 2500 km and width range from 1 km to 20
km, with very flat slopes.
The seasonal flooding regime has been characterized by means of inundation of the different land
types, which have been divided into five categories, ranging from very low to high land. Except
high lands (which cover 29% of the country’s total area), all other types are subjected to flood
inundation to different degrees. Excepting very low lands, human settlements can be found in all
other land categories.
Bangladesh generally experiences four types of floods. Flash floods occur during mid-April before
the on-set of the south-westerly monsoon. Rain-fed floods generally happen in the deltas in the
south-western part of the country and are increasing in low-lying urban areas. River floods are the
most common; the areas are inundated during monsoon season along the river and in cases far
beyond the riverbanks. Storm surge floods occur along the coastal areas of Bangladesh, which has
a coastline of about 800 km along the northern part of Bay of Bengal. In case of important cyclones
the entire coastal belt is flooded, sometimes causing great loss of lives. Coastal areas are also
subjected to tidal flooding from June to September.
During the last half-century, at least eight extreme flood events occurred affecting 50% of land area.
These extreme events are generated by excessive rainfall in the catchments. When water levels in
the three major river systems rises simultaneously and cross the danger marks (usually starting
from mid-July and continuing until mid-September), an extreme flood situation usually occurs all
over the country. Duration of these extreme events normally extends from 15 days to 45 days. This
was observed during those which occurred in 1987, 1988 and 1998, the latter having been the
severest one in terms of magnitude and duration.
1
Bangladesh Water Development Board (BWDB)
2
WMO/GWP Associated Programme on Flood Management
3. Flood management and mitigation strategies
Flood management strategies adopted in the country have continuously evolved over the last 50
years, in three distinct phases of their development, and with mixed experiences. Initially, the
emphasis was on structural measures through the implementation of some large-scale flood
control, drainage and irrigation (FCDI) projects. However, it was soon recognized that their
implementation involved large investments, as well as longer duration for their completion. It was
then opted for the construction of small and medium scale FCD projects so as to provide early
benefits. Thereafter, it was realized that water resources development should not be focused only
on agriculture but take also into account other sectors related to water resources utilization and
development. Environmental protection also came to the fore.
As a result, since the 1960’s about 628 large, medium and small-scale FCDI projects have been
implemented; they comprise levees and embankments, drainage channel improvements, drainage
structures, dams and barrages, pumping systems, etc. They have provided flood protection to
about 5.37 million ha of land, which is about 35% of the total area.
Non-structural measures such as flood forecasting and warning were later incorporated, as it was
felt that structural measures alone could not mitigate flood problems. The Flood Forecasting and
Warning System (FFWS), established in the 1970s, was modernized in 1996 and then again as of
2000. It now covers all the flood-prone areas of the country with 85 flood-monitoring stations, and
provides real-time flood information and early warning with lead-times of 24 and 48 hours. The
FFWS is currently assisting Government, disaster managers and the communities living in the
flood prone areas in matters of flood preparedness, preparation of emergency mitigation plans,
agricultural planning and rehabilitation, etc
In addition, more emphasis is now put on other non-structural means for flood mitigation, in
particular by adopting a policy of involving communities in flood management, the stopping of
encroachments on the flood plains through legislation controlling the developments in the flood
plains and wetlands. In addition, a new concept is being introduced of controlled flooding as per
desire of the stakeholders, instead of protecting some areas to make them completely flood-free. A
pilot project was established in which flooding is allowed in each unit as decided by the
stakeholders through consultation among themselves.
4. Flood and water management instruments
Since ancient time legal instruments were used for flood management in the country. During the
latter part of 19th
Century, many acts and rules for flood management were introduced, e.g.
Embankment Act, Drainage Act and Canal Act, etc. From the early sixties Government has
introduced some more acts to manage floods. Since there are some inconsistencies found in these
laws it has been decided to promulgate a unified law and work is now going on in framing a
National Water Code.
Bangladesh has developed a good hydrological data collection system all over the country, as well
as an integrated hydrological database with about 40 years of data. There is also a real-time water
level and rainfall data collection system from a selected number of stations for FFWS during
monsoon months. All these data are used for planning and design of different types of hydraulic
structures, construction of different infrastructures, etc.
During the last 40 years Government has invested approximately USD 4 billion in the water sector,
mainly for FCDI projects. Annually about USD 200 million are disbursed for water and flood
management.
3
WMO/GWP Associated Programme on Flood Management
5. Institutions responsible for flood management
About 53 central government organizations and 13 ministries are identified to be involved in water
and different stages of flood management, and a National Water Council (NWC) was set up to
coordinate all the various activities of the Agencies and Departments involved in the water sector.
Of those organizations involved in different stages of flood management, the following may be
mentioned:
(i) Water Resources Planning Organization - macro planning of water resources
management;
(ii) Bangladesh Water Development Board - feasibility studies, implementation, operation
and maintenance of flood management projects, real-time data collection for flood
forecasting and warning services, dissemination of flood information at national and
regional levels;
(iii) Joint River Commission - to conduct negotiations for data and information exchange on
trans-boundary rivers;
(iv) Bangladesh Meteorological Department (BMD) - long, medium and short range weather
forecasting and dissemination;
(v) Local Government Engineering Departments – implementation, operation and
management of small-scale FCD projects;
(vi) Disaster Management Bureau (DMB) - dissemination of all information on natural
disaster, including flood information at community level, flood preparedness awareness
building, etc.;
(vii) Directorate of Relief - conducting relief and rehabilitation operation in flood hit areas;
and
(viii) Local Government Institutions (LGI) - implementation of small scale flood management
projects, flood information dissemination, relief and rehabilitation of flood victims.
The principal national institution concerned with flood management is the BWDB. The JRC and
BWDB carry out international and regional data and information exchange. BWDB disseminates all
kinds of flood information to all related Government Departments and Organizations.
Flood management relating to water management at national level is co-coordinated by the
abovementioned National Water Council and the Ministry of Water Resources. Flood management
relating to disaster management is co-coordinated by the National Disaster Management Council,
particularly by the Ministry of Disaster Management and Relief. Over-all coordination during the
flood event is the responsibility of the latter Ministry and the Inter-Ministerial Disaster Management
Committee.
The Government has made flood management as a participatory activity. Up-dated Guide Lines
For Participatory Water Management have been prepared to involve all kinds of stakeholders, both
at national and local levels. Public consultation has been made compulsory for any flood
management project. Some pilot studies have recently been completed to ensure effective
peoples’ participation in dissemination, as well as in flood preparedness activities at the community
level. Methodologies were developed for constituting Community Based Organizations for flood
management. Intensive consultation and training were conducted for the local people to develop
their capacity for dissemination of flood information and preparedness.
6. Policy
In the early eighties, a National Water Plan was formulated to address various aspects of water
use and demand and the interests of different stakeholders involved in the water sector. A Flood
Action Plan was implemented from 1990-1996, on the basis of which a National Flood and Water
Management Strategy was formulated in 1996. It already included policy guidelines for peoples’
4
WMO/GWP Associated Programme on Flood Management
participation, Environmental Impact Assessment (EIA) and multi-criteria analysis during planning
process in all future water sector projects.
In 1999 the National Water Policy (NWPo) was introduced, which guides all the activities in the
water sector. Subsequently, a National Water Management Plan (NWMP) was prepared in 2001,
cross-cutting different sectors of national economy in the light of Integrated Water Resources
Management, to address conflicting water needs and to ensure equitable water use and balanced
economic growth, into the next 25 years. The Plan includes also the management of water-induced
disasters, e.g. floods, erosion and droughts. A Comprehensive Disaster Management Plan (CDMP)
and Disaster Management Guidelines were also prepared, in which the responsibilities of different
agencies involved in disaster mitigation activities are delineated during pre-disaster preparedness,
rescue and evacuation operation during disaster and post-disaster relief and rehabilitation.
7. Main lessons learned
Bangladesh has learnt many lessons from its experiences of the last 50 years in flood
management, namely:
• Flood management activities should not be a stand-alone approach but rather an integrated
approach in line with IWRM.
• Flood management should a combination of both structural and non-structural measures.
• The process of flood management should be a participatory one; especially communities
should be pro-actively involved.
• Flood management activities should be sustainable.
• Technical considerations should not preclude socio-economic considerations.
• Flood management should directly contribute to poverty reduction or alleviation in the
developing countries.
WMO/GWP Associated Programme on Flood Management
BANGLADESH: FLOOD MANAGEMENT
A.N.H. Akhtar Hossain
1
Abstract. Information is provided about the approach and long-year experience on flood
management in that country, with strategies that have seen continuous change after a number of
disastrous floods. Of interest is in particular the introduction of an integrated approach for flood
management, which has been reflected in recent plans for flood and water management
1. Location
Bangladesh is situated in the south Asian sub-continent. Because of its unique geographical
location and topography, it is one of the most flood-prone countries in the world. Approximately 20
to 25% of Bangladesh’s territory is inundated during the monsoon season. Such flooding provides
fertile agricultural land and the floodplains in the country are densely populated and intensely
utilized. On the other hand, at least 50 to 70% of the country’s territory is exposed to intermittent
extreme flooding that has far-reaching negative impacts on the national economy. Flood
management in Bangladesh is, therefore, perceived as an indispensable component of poverty
reduction initiatives.
2. Nature of floods
The country has a unique hydrological regime. It has 230 rivers, of which 57 are international,
Bangladesh in most cases being the lower riparian country. Of the three large transboundary river
systems (Ganges, Brahmaputra and Meghna), only 7% of their huge catchment areas lies in
Bangladesh. The major rivers have a length of 500 to 2500 km and width range from 1 km to 20
km, with very flat slopes.
The seasonal flooding regime has been characterized by means of inundation of the different land
types, which have been divided into five categories, ranging from very low to high land. Except
high lands (which cover 29% of the country’s total area), all other types are subjected to flood
inundation to different degrees. Excepting very low lands, human settlements can be found in all
other land categories.
Bangladesh generally experiences four types of floods. Flash floods occur during mid-April before
the on-set of the south-westerly monsoon. Rain-fed floods generally happen in the deltas in the
south-western part of the country and are increasing in low-lying urban areas. River floods are the
most common; the areas are inundated during monsoon season along the river and in cases far
beyond the riverbanks. Storm surge floods occur along the coastal areas of Bangladesh, which has
a coastline of about 800 km along the northern part of Bay of Bengal. In case of important cyclones
the entire coastal belt is flooded, sometimes causing great loss of lives. Coastal areas are also
subjected to tidal flooding from June to September.
During the last half-century, at least eight extreme flood events occurred affecting 50% of land area.
These extreme events are generated by excessive rainfall in the catchments. When water levels in
the three major river systems rises simultaneously and cross the danger marks (usually starting
from mid-July and continuing until mid-September), an extreme flood situation usually occurs all
over the country. Duration of these extreme events normally extends from 15 days to 45 days. This
was observed during those which occurred in 1987, 1988 and 1998, the latter having been the
severest one in terms of magnitude and duration.
1
Bangladesh Water Development Board (BWDB)
2
WMO/GWP Associated Programme on Flood Management
3. Flood management and mitigation strategies
Flood management strategies adopted in the country have continuously evolved over the last 50
years, in three distinct phases of their development, and with mixed experiences. Initially, the
emphasis was on structural measures through the implementation of some large-scale flood
control, drainage and irrigation (FCDI) projects. However, it was soon recognized that their
implementation involved large investments, as well as longer duration for their completion. It was
then opted for the construction of small and medium scale FCD projects so as to provide early
benefits. Thereafter, it was realized that water resources development should not be focused only
on agriculture but take also into account other sectors related to water resources utilization and
development. Environmental protection also came to the fore.
As a result, since the 1960’s about 628 large, medium and small-scale FCDI projects have been
implemented; they comprise levees and embankments, drainage channel improvements, drainage
structures, dams and barrages, pumping systems, etc. They have provided flood protection to
about 5.37 million ha of land, which is about 35% of the total area.
Non-structural measures such as flood forecasting and warning were later incorporated, as it was
felt that structural measures alone could not mitigate flood problems. The Flood Forecasting and
Warning System (FFWS), established in the 1970s, was modernized in 1996 and then again as of
2000. It now covers all the flood-prone areas of the country with 85 flood-monitoring stations, and
provides real-time flood information and early warning with lead-times of 24 and 48 hours. The
FFWS is currently assisting Government, disaster managers and the communities living in the
flood prone areas in matters of flood preparedness, preparation of emergency mitigation plans,
agricultural planning and rehabilitation, etc
In addition, more emphasis is now put on other non-structural means for flood mitigation, in
particular by adopting a policy of involving communities in flood management, the stopping of
encroachments on the flood plains through legislation controlling the developments in the flood
plains and wetlands. In addition, a new concept is being introduced of controlled flooding as per
desire of the stakeholders, instead of protecting some areas to make them completely flood-free. A
pilot project was established in which flooding is allowed in each unit as decided by the
stakeholders through consultation among themselves.
4. Flood and water management instruments
Since ancient time legal instruments were used for flood management in the country. During the
latter part of 19th
Century, many acts and rules for flood management were introduced, e.g.
Embankment Act, Drainage Act and Canal Act, etc. From the early sixties Government has
introduced some more acts to manage floods. Since there are some inconsistencies found in these
laws it has been decided to promulgate a unified law and work is now going on in framing a
National Water Code.
Bangladesh has developed a good hydrological data collection system all over the country, as well
as an integrated hydrological database with about 40 years of data. There is also a real-time water
level and rainfall data collection system from a selected number of stations for FFWS during
monsoon months. All these data are used for planning and design of different types of hydraulic
structures, construction of different infrastructures, etc.
During the last 40 years Government has invested approximately USD 4 billion in the water sector,
mainly for FCDI projects. Annually about USD 200 million are disbursed for water and flood
management.
3
WMO/GWP Associated Programme on Flood Management
5. Institutions responsible for flood management
About 53 central government organizations and 13 ministries are identified to be involved in water
and different stages of flood management, and a National Water Council (NWC) was set up to
coordinate all the various activities of the Agencies and Departments involved in the water sector.
Of those organizations involved in different stages of flood management, the following may be
mentioned:
(i) Water Resources Planning Organization - macro planning of water resources
management;
(ii) Bangladesh Water Development Board - feasibility studies, implementation, operation
and maintenance of flood management projects, real-time data collection for flood
forecasting and warning services, dissemination of flood information at national and
regional levels;
(iii) Joint River Commission - to conduct negotiations for data and information exchange on
trans-boundary rivers;
(iv) Bangladesh Meteorological Department (BMD) - long, medium and short range weather
forecasting and dissemination;
(v) Local Government Engineering Departments – implementation, operation and
management of small-scale FCD projects;
(vi) Disaster Management Bureau (DMB) - dissemination of all information on natural
disaster, including flood information at community level, flood preparedness awareness
building, etc.;
(vii) Directorate of Relief - conducting relief and rehabilitation operation in flood hit areas;
and
(viii) Local Government Institutions (LGI) - implementation of small scale flood management
projects, flood information dissemination, relief and rehabilitation of flood victims.
The principal national institution concerned with flood management is the BWDB. The JRC and
BWDB carry out international and regional data and information exchange. BWDB disseminates all
kinds of flood information to all related Government Departments and Organizations.
Flood management relating to water management at national level is co-coordinated by the
abovementioned National Water Council and the Ministry of Water Resources. Flood management
relating to disaster management is co-coordinated by the National Disaster Management Council,
particularly by the Ministry of Disaster Management and Relief. Over-all coordination during the
flood event is the responsibility of the latter Ministry and the Inter-Ministerial Disaster Management
Committee.
The Government has made flood management as a participatory activity. Up-dated Guide Lines
For Participatory Water Management have been prepared to involve all kinds of stakeholders, both
at national and local levels. Public consultation has been made compulsory for any flood
management project. Some pilot studies have recently been completed to ensure effective
peoples’ participation in dissemination, as well as in flood preparedness activities at the community
level. Methodologies were developed for constituting Community Based Organizations for flood
management. Intensive consultation and training were conducted for the local people to develop
their capacity for dissemination of flood information and preparedness.
6. Policy
In the early eighties, a National Water Plan was formulated to address various aspects of water
use and demand and the interests of different stakeholders involved in the water sector. A Flood
Action Plan was implemented from 1990-1996, on the basis of which a National Flood and Water
Management Strategy was formulated in 1996. It already included policy guidelines for peoples’
4
WMO/GWP Associated Programme on Flood Management
participation, Environmental Impact Assessment (EIA) and multi-criteria analysis during planning
process in all future water sector projects.
In 1999 the National Water Policy (NWPo) was introduced, which guides all the activities in the
water sector. Subsequently, a National Water Management Plan (NWMP) was prepared in 2001,
cross-cutting different sectors of national economy in the light of Integrated Water Resources
Management, to address conflicting water needs and to ensure equitable water use and balanced
economic growth, into the next 25 years. The Plan includes also the management of water-induced
disasters, e.g. floods, erosion and droughts. A Comprehensive Disaster Management Plan (CDMP)
and Disaster Management Guidelines were also prepared, in which the responsibilities of different
agencies involved in disaster mitigation activities are delineated during pre-disaster preparedness,
rescue and evacuation operation during disaster and post-disaster relief and rehabilitation.
7. Main lessons learned
Bangladesh has learnt many lessons from its experiences of the last 50 years in flood
management, namely:
• Flood management activities should not be a stand-alone approach but rather an integrated
approach in line with IWRM.
• Flood management should a combination of both structural and non-structural measures.
• The process of flood management should be a participatory one; especially communities
should be pro-actively involved.
• Flood management activities should be sustainable.
• Technical considerations should not preclude socio-economic considerations.
• Flood management should directly contribute to poverty reduction or alleviation in the
developing countries.
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