An Overview of Impact of Flood in Bangladesh and Options for Mitigation

1. An Overview of Impact of Flood in Bangladesh and Options for Mitigation A. N. H. Akhtar Hossain PEng Honorary Secretary General, The Institution of Engineers, Bangladesh & Managing Director, Dhaka WASA

2. Points to be highlighted • Causes of Flood • Impact of Flood • History of Flood Management • Mitigation Options

3. Types of Flood • Flash Flood • Rainfed Flood • River Flood • Storm Surge and Tidal Flood • Urban floods

4. Major Causes of Floods in Bangladesh • Large volume of flow from transboundary rivers in very short period of time (June-October) • Intensive rainfall within the country • Very flat topography • Higher sea level during monsoon • Synchronization of flood peaks • Siltation of the drainage routes • Breaching and overtopping of flood protection embankments • Human intervention and encroachment of rivers and floodplains

5. Overview of some historical flood event • 1987 Floods: Heavy rainfall in Northwest Region • 1988 Floods: High floods in Brahmaputra and Ganges Basins; Flood peaks synchronised • 1998 Floods: Four successive flood peaks in Brahmaputra; higher sea level. • 2004 Floods: High rainfall in northern and northeastern catchments; high water level at Chandpur

6. More than 68% of the inundated in 1998

7. More than 38% of the inundated in 2004

8. Socio-economic Implications Historical flood events – extent and crop damage

9. Event Impact 1954 floods Affected 55% of country 1974 flood Moderately severe, over 2,000 deaths, affected 58% of country, followed by famine with over 30,000 deaths 1984 flood Inundated 52,520 sq-km, cost estimated at US$ 378 million 1987 floods inundated over 50,000 sq-km, estimated damage US$ 1.0 billion, 2055 deaths 1988 floods Inundated 61% of country, estimated damage US$ 1.2 billion, more than 45 million homeless, between 2,000-6,500 deaths 1998 floods 1,100 deaths, inundated nearly 100,000 sq-km, rendered 30 million people homeless, damaged 500,000 homes, heavy loss to infrastructure, estimated damage US$ 2.8 billion 2004 floods Inundation 38%, damage US$ 6.6 billion, deaths 700, affected people nearly 3.8 million

10. RELATED POLICY, PLAN AND STRATEGY • 1957, Krugg Mission Milestones • 1964, IECO Master Plan • 1972, IBRD Plan • National Water Plan 1, 1986 • National Water Plan 2, 1991 • National Env. Policy, 1992 • Flood Action Plan, 1989-95 • National Forest Policy,1994 • BWFMS, 1995 • National Fisheries Policy,1998 • National Water Policy,1999 • National Agri. Policy,1999 • Guidelines for Participatory • Water Management, 2000 NWMP, 2004

11. FLOOD CONTROL MEASURES • Structural:Dam, Barrage, Regulator, Sluices, Embankment, Channel Improvement, River Training & Bank Protection Works etc. • Non-structural: Flood Forecasting & Warning System, Flood Proofing, Crop Diversification

12. Completed FCD Projects – approx. 600

13. Non Structural Measures • Flood Forecasting & Warning System since 1972 • From 1990 FFWS has been developed with Hydrodynamic model • FFWS has the capability to produce Flood Inundation Status on Daily basis • Flood Forecasting and Warning System for all flood prone areas having 85 Flood Monitoring Stations of which 46 are real Flood Forecast Stations • Flood Proofing has been practiced since time immemorial in the low lying areas through raising the platform for homesteads • Crop Diversification is also been practiced

14. Benefits from Flood Management Measures • Cereals Production (2001-2002) • - Incremental 8.535 million MT Equivalent • to appx. US$ 1.0 billion • FFWS plays an important role in reducing losses as well as saves life and property • Poverty Reduction: • Directly • - LCS, EMG, CMG

15. Options for Flood Mitigation Stages Flood preparedness Post-flood Rehabilitation Flood Response

16. Flood Preparedness Measures • Flood zoning and risk mapping: A comprehensive approach is required to develop flood zoning and risk maps for coordinated development and risk management in floodplains • Rationalization and adequate maintenance of existing FCD projects • Flood management modeling: to study any development options in the floodplains in an integrated manner based on proper scientific basis • Erosion prediction and monitoring: making use of available modeling integrated with remote sensing and GIS technology a nation-wide erosion prediction and monitoring system should be immediate instituted

17. Flood Preparedness Measures • Drainage Improvement:The natural drainage need to dredged and made free from encroachment to bring back the original conveyance capacity. Canal Digging program may be strengthened with proper technical guidelines and effective monitoring. • Offtake Maintenance:It is important the offtake of the rivers are regularly dredged to allow flood flow distribution in wider areas. • Integrated Floodplain Management:There should be government guidelines for any development in the floodplains which would pave the way for an Integrated Floodplain Management.

18. Flood Preparedness Measures • Urban Flood Management:There is a need for immediate actions to free the natural drainage routes from encroachment, design and implement sustainable drainage management system for each of the urban areas. • Improvement of Lead-time for Flood Forecast:The lead-time of forecasts could be extended using climate forecasts. The CFAB project has paved the way-the development made through CFAB should be carried forward. • Flood Proofing and Shelters:Various flood proofing measures could be adopted deep-flooding areas. One of the options may be to build clustered habitats with all the civic amenities. This may be undertaken on a pilot basis under Asrayan Project for the poor in the Haor areas.

19. Flood Response Measures • Updating and further development of the Standing Order for Disaster Management • Development and implementation of an ICT based Flood Response system which should also include a nation-wide network of flood information database by connecting databases of various agencies involved in flood response activities. Such a system could be developed based on internet and wireless communication technologies; • Training and capacity building of field officials and community workers, volunteers and NGO staffs in flood fighting and relief activities.

20. Flood Response Measures Awareness building: It is imperative that for implementing participatory approach in flood disaster management and to make it effective, awareness about any disaster event and the role of all concerned should be clearly understood. For this purpose the government, NGOs and others concerned should undertake concerted efforts.

21. Post Flood Reconstruction and Rehabilitation • Methods and tools for damage assessment: One of the constraints in responding to any disaster and mobilizing resources for reconstruction and rehabilitation is reliable data on flood damage. There are no methods or tools available in the country. Measures should be taken to develop such tools and methods • Coordination:The limited resources of the government should be properly mobilized and coordinated. For this all agencies working in the post-flood rehabilitation and reconstruction should carry out their activities in a transparent and coordinated manner. There should be central flood rehabilitation body to coordinate such activities.

22. General Recommendations • Regional cooperation: As more than 90% of the flood flow originate from outside the country, Bangladesh alone cannot solve the flood problem. For effective flood management basin wide approach with concerted regional participation may be pursued. A regional flood management initiative should be initiated with participation from all co-riparian countries. • The Indian River Link Project: The proposed Indian river link project would be a disaster for the society, economy and the ecology of Bangladesh. Immediate actions are required in the following areas’ • to foster dialogue with the Indian side on this issue. • Initiative from people to build awareness • Scientific studies to understand the impacts

23. Thank you for your kind attention

24. Average inflow Total Basin Area 1.72 million sq km Only 7% of basin area lies within Bangladesh 80% in 5 months

25. Lower Megna Max Q 180,000 m3/ s Min Q 4,000 m3/ s Annual Variation of Major River Discharge Brahmaputra-Jamuna India Meghna India Ganges-Padma Bay of Bengal Myanmer

26. 4600 4200 1500 2600 1900 1700 2200 2000 2100 2800 2900 • Annual Ave. Rainfall:2300mm • Annual Maximum > 4500mm (northeast Bangladesh) Cherapunji (in INDIA) Worlds highest rainfall

27. Topography of Bangladesh • -Land elevation of 50% of the country is within 5 m of MSL • 68% of the country is vulnerable to flood • 20-25% of the area is inundated during normal flood

28. 1998 Floods Synchronisation of Flood Peaks on Sept 10 Jamuna River at Bahadurabad Ganges River at Hardinge Br. Meghna River at B Bazar

29. Higher sea level in monsoon Monsoon

30. River siltation Three river systems carry about 1.8 ~2 billion tons of sediment every year. A large volume of this sediment flow is deposited within the country on river beds and flood plains.

31. Breach/failure of Embankments

32. Human Interventions Kobadak Betna Ichamati Beel Dakatia in 1998 Satkhira in 2000

33. Severe flooding Moderate flooding Dry Flood zoning & Risk Mapping

34. Suggest Flood Proofing Suggest Flood Proofing High risk zone Flood Proof existing infrastructure Flood Proof existing infrastructure Beyond Probable Flood Beyond Probable Flood Risk Mapping & Development Guidelines 100 year flood 50 year flood 10 year flood

35. Erosion Prediction Using Morphological Models Sirajganj Bhuapur Jamuna Brdige Site

36. Policy issues Monitoring & Measurement Forecasting Decision Support Systems Water system Management/ support Knowledge Information Feedback Knowledge Information Feedback Decision Studies Projects Investment Stakeholders ICT based Flood Response System

37. Knowledge provider Knowledge Consumer Interaction Consultation Sharing Stakeholders User community • An assessment of the cost if a certain phenomenon were to occur with a particular intensity • This may be quantified to provide the cost of occurrence of a phenomenon Knowledge Consumer Forecaster Knowledge provider Probabilities of a particular event occurring at a particular time at a particular intensity

38. Dredging & Canal Digging for Drainage Improvement

39. Offtake Management Ganges River Old Brahmaputra Offtake Dhaleswari offtake Gorai offtake Gorai

40. - Drainage Projects - Flood Control - Flood Control & Drainage - Flood Control, Drainage & Irrigation - Irrigation & Drainage - Irrigation Projects Rationalisation of FCD/FCDI Schemes 65% of flood prone lands now under flood management 617 projects so far completed

41. Before After

42. Flood Proofing in Haors & Low Lands

44. Top Width Berm Modified Embankment Section Top Width River R/S Country R/S Normal Embankment Section

45. Awareness Building & Motivation

46. Integrated Management of Transboundary River Basins: From the Mountain top to the Sea

47. Water a Medium of Cooperation in GBM Basins Flow Augmetation Net potential 5339 m3/s Flood Management Flood Forecasting Hydropower For around 400,000 Km2 Navigation Potential 233,800 Mw Present 22,722 Opening up Nepal, Bhutan and the Northeast to the sea Participatory Water Management Private Public Partnership Environmental Conservation & Restoration Integrated Water Resources Management Fragmented Development

48. Climate Forecast Application in Bangladesh (CFAB) Partners: Georgia Tech University, Univ. of Colorado, Asian Disaster Preparedness Centre, FFWC, BMD, DAE, IWM, CEGIS and others • Develop forecasts schemes for Short (1-6 days), medium (20-30 days) and long (1-6)months time scales • Incorporate these schemes into the Bangladesh’s flood and weather/climate forecasting systems • Produce systems that are transportable in the short-term to Bangladesh institutions CFAB presently focuses on making available the forecast products for agriculture sector which accounts for nearly 30% of the country’s GDP

49. Short-range forecasts of Basin Discharge 1-6 days Short-range forecast schemes use rainfall over the Ganges and Brahmaputra catchment areas provided by ECMWF. Statistical Analysis. Provides river discharge into Bangladesh 1-6 days ahead. Schemes will increase FFWC forecast in Bangladesh to 8-10 days Brahmaputra Basin 552,000 sq.km C H I N A N E P A L I N D I A BHUTAN Ganges Basin 1,087,000 sq.km I N D I A MYANMAR BANGLADESH Meghna Basin 82,000 sq.km B A Y O F B E N G A L

50. date of forecast: 04-09-2003 Series 1 Observed Lower Bound Upper Bound Forecasting with Longer Lead-time 5-day Hindcasting For 1998 5-day Forecasting For 2003 X 104 m3/s