1. Communities and Institutions for Flood Resilience
Turning Tides?
Learning from our futures
Resilient Adaptation to Flood Risks under
Urban Growth and Climate Change Dynamics
Promovendus: Farhana Ahmed
Promotor: Prof. Chris Zevenbergen
Supervisors: Berry Gersonius, William Verbeek
2 November, 2012

2. Research Background
• Cities are prone to hazards with 233 out of 633
cities or urban agglomerations and 663 million
inhabitants vulnerable to high risk of flooding
• World urban population is presently more than
50%, expected to reach 67% by 2050
• Of which, 86% population in the more developed
regions and 64% in the less developed regions.
• Urbanization rate of 1.32% in less developed
regions, is more than developed region with 0.4%
• Climate change will increase precipitation and
more frequent flooding events.

3. Adverse Effects of Flood
Physical effects
– Damage to structures and
– Infrastructure
Environmental effects
– Water quality through
contamination of drinking
water and water bodies
– Public health issues and
– Aesthetic influence
Socio-economic effects
– Economy
– Societal disruption • Within 1995-2004, flood
contributed to 20% death toll
• 33% economic losses

4. Project Background
Communities and institutions for flood resilience:
enhancing knowledge and capacity to manage flood risk
in the Bangladeshi and Dutch Deltas
 Partners:
Dutch institutes
(Wageningen University,
UNESCO-IHE) &
Bangladeshi Institutes
(IWFM-BUET, CEGIS)
 Analyze the strategies and
policies of rural, urban,
epistemic and policy
communities to reduce
flood risks and
vulnerabilities
 Period: 2012-2016

5. Integration among the PhDs under WOTRO
Publication and
Integration process among the PhDs
Dissemination
Delta lessons and Water Management Practices
in the Dutch-BD deltas
PhD-1:Dealing with uncertainty: the delta
knowledge agendas in the Netherlands
PhD
and Bangladesh
Thesis
Urban-Rural Flood Management
Practices in BD
PhD-2: Assessment of rigid vs flexible flood Publications
PhD-3: Rural climate-change adaptation adaptation and mitigation sStrategies under
in Bangladesh: strengthening flood (Journals/Book)
dynamic urban environment and changing climate
resilient communities
Adaptation and Mitigation Strategies
in BD-Netherlands
PhD-4: Linking climate change adaptation Workshops/ Website
and disaster risk reduction with floods: seminars
towards resilient deltas Dissemination

6. Flood Risk Assessment and Adaptation
Approaches
• Qualitative vs Quantitative assessment
• Resilience (Socio-technical) approach vs robust engineering approach for Flood
Risk Mitigation and Management
• Different Approaches: Adaptive Policy Making (APM), Adaptation Tipping Point
(ATP), Real-In-Options (RIO), and Adaptation Tipping Point - Adaptation
Mainstreaming Opportunity (ATP-AMO)
Top-down
ATP’s in water management Risk Management
Static
are the specific boundary APM
conditions where technical,
economic, spatial or societal
acceptable limits are ATP, Exploratory
RIO Modelling Adaptation
exceeded. Caused- Adap
tation
Effect-based/ Policy
based/impact Decision Analysis Adaptation Pathways vulnerability Pathways
ATP-AMO
Dynamic
Bottom-up

7. Gaps in the State of the Art
• Uncertainty in urban growth scenario (Planned and
unplanned)
• Uncertainty in climate change / flood predictions
• Lack of adequate/accurate data
• Constraints for adaption (financial constraint, large-scale
in-migration, gap in technical knowhow)

8. Objectives
to identify the impacts of changing climate and urbanization on urban
flooding and to assess the effectiveness of management, including flood
mitigation and adaptation. The specific objectives are:
I. Tailor the adaptation tipping point (ATP) method to a constrained
context such as experienced in developing countries.
II. Extend the traditional application of the ATP method through the
incorporation of multiple drivers, namely climate change and urban
growth.
III. Demonstrate the extended ATP method for the current flood risk
management (FRM) strategy for Dhaka.
IV. Develop alternative FRM strategies including multi-layer safety for
Dhaka by taking a combined top-down/bottom-up approach, and assess
these strategies with the extended ATP method.
V. Compare the effectiveness of multi-layer safety for adapting to
increasing flood risks between Bangladesh and the Netherlands.

9. Research questions
I. How can the ATP method be adapted to a developing country
context, in which management objectives may be lacking, not
well defined or exceeded?
II. How can the spatio-temporal dynamics of (planned and
unplanned) urban growth be incorporated into the ATP method?
III. What are the (intermediate) goals, measures and critical ATPs of
the current FRM strategy of Dhaka?
IV. Which alternative FRM strategies can be identified for Dhaka,
and are these strategies effective in postponing the critical ATPs?
V. Is multi-layer safety an effective way to adapt to changes in flood
risk in urbanised delta areas?

10. Dhaka City-The Case Study
• Area of DMA is 360 sq.km and DAP area
is 1528 sq.km (590 sq mile)
• Population of Dhaka city: 12 million
Turag river
(2010)
• DWASA: key agency for water supply Tongi Canal
system, sewerage and drainage (since
1963)
Balu
• Present water demand: 2200 MLD River
• Water demand: 91% demand is met up
by 4 SWTPs and 575 DTWs
• Source of water: 87% water from DTWs Lakhya
River
 Five rivers: Turag, Buriganga, Dhaleshwari,
Lakhya, Balu and Tongi canal
Buriganga
 Ground water: Relatively low depth of River
aquifer
 Rainfal: 2400 mm average annual rainfall Dhaleswari
(between 2001-2008, NWRD) River

11. Dordrecht-The Case Study
• in the delta of the rivers Rhine and Maas and is
situated in the transition area between rivers and
sea.
• 118 thousand inhabitants with a population of 1500
inhabitants per km2
• 99 km2 of which 19 km2 consists of surface water.

12. Change in Builtup area (1993-2007) Change in Vegetation area (1993-2007)
23% to 47% 58% to 40%

13. Flood map of 1988 Flood map of 1998
•75% area of western part inundated •23% area of western part inundated
•Duration of 3 weeks •61 wards were affected
•Flood height higher than 1998 (3-4.5m) •Duration was 2 months
•2.5 million people affected Data Source: IWM

14. Flood map of July-Aug 2004 Flood map of September 2004
•600 mm rainfall from 11-15th Sept
•Inundated Area 40% •Average 297 mm
•341 mm rainfall on 13th Sept

15. Flood map of August 2007 Flood Map of July 2009
• Above average year flooding
• Less severe than 2004, 1998 or 1988 • Highest rainfall of 333 mm in 24 hrs
• Record number of patients with diarrhoea (21,401 in between 27th-28th July.
August), dehydration and cholera. (Source: ICDDRB) • 1 day maximum rainfall of 448mm

16. Dhaka City Flood Management Systems
Flood Infrastructure
Western Part (136 sq km)
• Fully flood protected
• Inundation occurs due to
intensive rainfall
• Inadequate drainage systems
Eastern Part (124 sq km)
• No flood protection
• Encroachment of water bodies
• Lack of coordination between
agencies

17. DHAKA: LOCATED IN THE DELTA FORMED BY GANGES -
BRAHMAPUTRA/JAMUNA -MEGHNA SYSTEMS

18. Deviation of Rainfall from daily normal
(1961-1990)
40 120
100
30
80
Rainfall deviation (mm)
Rainfall deviation (mm)
20
60
10 Hydrographs of Buriganga at Dhaka 40
0 (1988-2009) 20
1-Jul 11-Jul 21-Jul 31-Jul 10-Aug 20-Aug 30-Aug 9-Sep 19-Sep 29-Sep 0
-10 1-Jul 11-Jul 21-Jul 31-Jul 10-Aug 20-Aug 30-Aug 9-Sep 19-Sep 29-Sep
-20
-20 -40
Dates Dates
Fig. 6: Temporeal variation of the deviation of daily rainfall during July-September 1988
Fig. 7: Temporeal variation of the deviation of daily rainfall during July-September 1998
from the daily normal of 1961-1990
from the daily normal of 1961-1990
400
350
300
Rainfall deviation (mm)
250
200
150
100
50
0
1-Jul 11-Jul 21-Jul 31-Jul 10-Aug 20-Aug 30-Aug 9-Sep 19-Sep 29-Sep
-50
Dates
Fig. 8: Temporeal variation of the deviation of daily rainfall during July-September 2004
from the daily normal of 1961-1990

19. Review of Planning Initiatives
Dacca Master Plan, 1958, DIT
 Basically a land use plan prepared for 20yr period.
Dhaka Metropolitan Development Plan (DMDP) 1995, by RAJUK (MOHPW)
 DMDP includes:
a) Structure Plan (SP) 1995-2015
b) Urban Area Plan (UAP)/Master Plan (1995-2005)
c) Detailed Area Plan (DAP)
 SP provides long term strategy for growth, spatial and sectoral policies
 UAP, a mid term plan, includes Resource maps, Interim management report &
Multi sectoral investment program
 DAP provides detailed planning for specific sub areas.
Detail Area Plan (DAP)
 Approved by cabinet on 21st June, 2010
 Includes 3.4 lakh acres (excluding restricted areas)
 Provides detailed planning proposals for specific sub-areas of Dhaka
 Objective is to prevent flooding & ease the traffic congestion

20. Review of Planning Initiatives
Flood Action Plan (FAP 8A and FAP 8B)
 Prepared in 1988 for flood protection and drainage of the Greater Dhaka City
 FAP-8A comprises the East area (124 km2) of Dhaka city and FAP-8B comprises of
West area (136 km2) of Dhaka city.
 FAP-8B program proposes construction of drainage facilities along with Natural
drainage khals/canals, Natural storage and reservoirs of storm water
BANGLADESH CLIMATE CHANGE STRATEGY & ACTION PLAN 2009
 Adapt of climate change threats
 Contains two parts
 First part based on physical and climatic contexts, core socio-economic realities
and policies in the country and the consequent rationale for a strategy on climate
change
 Second part proposes interventions on six thematic areas: i) Food Security, Social
Protection & Health, ii) Comprehensive DM, iii) Infrastructure, iv) Research &
Knowledge Management, v) Mitigation & Low Carbon Dev., vi) Capacity Building
& Institutional Strengthening

21. Some Ongoing Projects
 DWASA projects, funded by JICA, include khal improvement,
main drains, construction of culvert and dredging.
 Badda urgent project to remove water logging (DWASA)
 Dholai Khal Rehabilitation and area development (DCC/World
Bank)
 Detail design of FAP 8B, funded by ADB which includes
strengthening of the western embankment with pumps and
sluice gates.
 Bangladesh Delta Plan Preparatory phase
 CORFU project

22. Future Planning Initiatives
Bangladesh Delta Plan
 draws experience from the
"Netherlands Delta Plan 2100“
 will be incorporated in the sector plans
 will be implemented through dev.
programmes of GOs and NGOs
 appropriate institutional arrangement
 funding source from govt. revenue and
development budget and development
partners
 a holistic long term (50 to 100 years)
integrated strategy plan for Bangladesh
 to achieve long term sustainable
development through adaptive water
governance

23. Proposed Methodology for the study
Input Process Output
Landuse Urban Urban
Demography Growth Modelling Growth Scenarios
DEM
Rainfall Flood Flood
River Water level Risk Modelling Scenarios
Climate change scenarios
Urban Drainage System
Urban Development Adaptation Adaptation
Policies & Plans Assessment Tipping Points
Climate Change Policy
and Action Plan
Flood Risk Management
& Adaptation Strategies

24. Urban growth scenarios

25. 2040
2050
2035
2025
2030
2015
2010
2045
2020
2060
2055

26. Flooding under different UG scenarios

27. Conclusion/Concerns
 Dhaka is in its incumbent stage of implementation of the DAP
 Urban growth’s threshold value have to identified and taken
into consideration at planning/policy level
 Climate change effects needs to be specific and concise to be
able to help set the standards for decision making
 Adaptation tipping points and turning points needs to be
identified
 Adaptive delta management approach in perspective of
changing urban and climate environment needs to be
examined
 Flood management with inclusion of flexible and rigid
strategies need to be compared to find the best combination