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The Ganges Basin Development Challenge (GBDC)
Increasing the resilience of agricultural and aquaculture systems in the
coastal areas of the Ganges Delta
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Water for a food-secure world
Tasks
• Who work in GBDC• Why GBDC• What GBDC is• How it works• Where it works• Your support
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Water for a food-secure world
THE BD GANGES TEAM
BAU BUET BFRI BRAC BWDB LGED IRRI
IWM IWMI PS&TU SRDI Shushilan WFC
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Why? Poverty in Coastal Zone of Bangladesh
• Among world’s poorest, most food insecure, vulnerable
• 75% of households (HH) with 0.2-0.6 ha; HH income ~70000 BDT
• 80% of population income < national poverty line
• Too much water in rainy season• Salinity and lack of fresh water in
dry season
BBS / WorldBank / WFP (2009)
With advances in sciences, innovation and improved understanding of socio economic issues ….There are opportunities for livelihood improvements. GBDC is
optimistic about a more productive and prosperous BD coastal zone
GBDC
Reducing poverty, improving resilience, through improved water
governance and management and intensified and diversified agricultural and aquaculture systems in brackish water of the
coastal Ganges.
We envision that after 10 years of GBDC……..
• Livelihood– Reduce food insecure HHs by 50%; increase HH
income by $100/year– Disadvantaged groups and women are empowered– Increase resilience (farmers ability to cope with
effects of vulnerability)• Production
– Annual agricultural/aquaculture outputs increased by 50%
– 50% of HHs have 2 crops/year, diversified with high value non-rice crops and/or aquaculture
– Income from “homestead” increased by 50%• Policy
– Enabling crop diversification and intensification– Coherent policies and institutions on water
management
Polder 31
Polder 30
River
Inlet to sluice gate
Sluice gate on river side
Sluice gate inside the polder
How? • Develop improved, intensified and
diversified agric and aqua systems and homestead
• Better water governance and management
• Quantify salinity and water dynamics: present and future
• Identify extrapolation domains and propose land use maps
• Enhance impact through coordination, stakeholder participation and policy advocacy
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Where?
Barisal: Patuakhali, BargunaKhulna: Khulna & Satkhira
except the Sundarbans
Andes • Ganges • Limpopo • Mekong • Nile • Volta
1S or1S-1R
2
S+C - F
14
2R/U
5
3R/U
3R/U
6
1S or1S-1R
3
xS: No. of shrimp crops
xR: No.of rice crop
xR/U: No. of rice or upland cropS+C-F: Shrimp+Crab - Fish
Land use zoning proposed by project in 2000
Land use 2005
Land use 2000To serve you better, we need your support
You are policy makersCritical feedbacksGuidance & collaboration
Policy uptake
Frequent interactions
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Thank You
Ganges Basin Development Challenge
Adoption of new technologies- Salinity and
External Drivers
POLDER-43/2f
Salinity Dynamics in the Peripheral river of Polder-43/2F
Kharif-2 Rabi Kharif-1
POLDER-30
Kharif-2 Rabi Kharif-1
Salinity Dynamics in the Peripheral river of Polder-30
POLDER-3
Salinity Level remain below 2 ppt form end of July to Early December
Salinity Dynamics in the Peripheral river of Polder-3
Polder-30
Road Network and Change of Drainage Pattern
Water flow Models
Water Flow boundary
Q
WL WL WL WL
WL
Water Flow Model ofSouth-West Region
2 Dimensional Model (Bay of Bengal Model)Water flow boundary from SWRMWater level from Global Tide Model
QQQ
WL
Water Flow at Pussur River
Water Level at Pussur River
Average of Peak water level during kharif-2
Scenarios
Single or combination of the external drivers
2030 and 2050
Drivers and Scenarios
Final List of Key External Drivers
• Experts, • service providers, practitioners and academicians• Policy planners • representatives from other G’s• Stakeholders and community representatives
Participants
1. Change in transboundary flow +Population growth+Land use change+Climate change (including ppt, temp & SLR)A2+ Urbanization
2. Change in transboundary flow +Population growth+Land use change+Climate change (including pptn, temp & SLR)A1B+ Urbanization
Scenarios from the workshop
Effects of External drivers on Salinity intrusion and Fresh water availability
15 Km
2 PPT Salinity line moves 10-15 km upwards 800 Sqkm more area is likely to be affected
2 PPT Salinity line moves 12-18 km upwards 1050 Sqkm more area is likely to be affected
• In the low saline zone freshwater is available for the whole year at present and future and three crops can be established instead of one crop at present;
• Gravity irrigation is feasible during Aman Crop;• Costal polder needs improved water management with additional drainage
and flushing sluices and ensuring proper operation of gates;• Internal road network needs adequate number of cross-drainage structure
for drainage improvement;• Excavation of internal drainage khal for drainage improvement and water
storage for agriculture;• In the high saline zone, unauthorized pipes/structure are used for saline
water supply can be replaced by few number of flushing sluices for better water and conflict management and safety of the embankment ;
• The effects of external drivers on water resources is significant and needs to be considered in future plannning.
Key Findings
THANK YOU
Adoption of improved technologies requires improved water management in coastal polders
The opportunity• Tremendous potential to improve food security &
livelihoods in the coastal zone through – improved crop & aquaculture technologies – cropping system intensification & diversification
• CPWF Ganges program has demonstrated that with – new varieties– timely crop establishment – improved crop & water management, cropping system intensity & the productivity of the
coastal lands can be greatly increased - in all seasons.
The opportunity: low saline area
• where freshwater is available in the rivers for 10-11 months a year, such as parts of Barguna District
– Aman-Grasspea (rice: 3 t/ha, grasspea: 0.5 t/ha) – Aus-Aman (rice: 6 t/ha)
can be replaced by
– Aus-Aman-Boro (rice: 16 t/ha)– Aus-Aman-Rabi (rice: 10 t/ha, sunflower: 3 t/ha, maize: 8 t/ha)
10 Apr
30 June
10 July
15 Nov 05Apr
Rabi (130-140 d)
1 Dec
T. Aman (130-140 d)
Aus (100-105 d)
A M J J A S O N D J F M A
Aus-Aman-Rabi Cropping System
The opportunity: moderately saline area
• Where freshwater is limited during the dry season, such as parts of Khulna District,– Productivity of the traditional Aman-Sesame
or single Aman systems (rice: 2 t/ha, sesame: 0.5 t/ha)
can be increased several-fold through
– Aman-Rabi (rice: 4 t/ha, maize: 8 t/ha, sunflower: 3 t/ha)– Aman-Boro (rice: 9 t/ha)
15 July
15 Nov 30 AprRabi (120-140 d)
Dec/Jan Aman (140 d)
M J J A S O N D J F M A M
Terminal Drainage
Aman-Rabi Cropping System
The opportunity: high saline area
• where water salinity too high for dry season agriculture, e.g. parts of Satkhira District, productivity of shrimp culture can be greatly enhanced by new technologies for higher aquaculture production & reduced risk
• Shrimp culture (shrimp: 200 kg/ha) can be replaced by more resilient systems of [Shrimp+Fish]-[Rice+Fish]
(shrimp: 200 kg/ha, rice: 3 t/ha, fish: 700-1200 kg/ha) • Win-win-win: greater food security + cash income
without damaging the environment.
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Wet season Dry season
Gher preparation
Seedling
Bagda Rice+Fish
Improved aquaculture-rice system
Drain out saline water, expose gher soil to rainfall to leach down soil salinity
Poorly-drained gher in polder 3 Well-drained gher
Realising the opportunity
Requires ability to:– drain fields– intake water of the desired quality – store fresh water for irrigation
This is NOT the current situation………
Aman rice field in Patuakhali
Aman rice field in Patuakhali
Aman rice field in Patuakhali
Aman rice field in Patuakhali
Rice-Fish cultivation in Ghers in Satkhira(inundated due to rainfall during 3-5 September 2012)
How to realise the opportunity?
• Successful large-scale implementation of the opportunities requires – a change in mind set & investments in agriculture,
aquaculture, & water management. – Need to focus on polder level water management; a
pre-requisite• Effective investment in water management requires
fundamental changes in thinking about the roles of the polders, polder design & infrastructure, & the institutional set up to manage the water of the polders
Re-defining the roles of polders
• Each polder needs to be considered as an integrated water management unit, serving the production systems
• The original role of the polders was to enable one crop of tall, long duration traditional aman rice (HYVs did not exist)
• HYVs & improved cropping system technologies now available, but with different requirements from traditional aman
How will good drainage help?
• Improved drainage will– enable adoption of HYV in rainy season (aman)– timely establishment of rabi crops– ability to grow higher yield/value rabi crops – adequate leaching of salt from shrimp ghers
prior to transplanting the aman crop– cropping system intensification
How to increase storage volume inside polders?
• Increased fresh water storage capacity during the dry season requires re-excavation of existing canal networks (will also improve drainage!)
Effective water management at polder level require separation of lands on the basis of land topography to form a small water management unit by about 50 cm high farm levee
Changing institutional set ups• Treating the polders as unified water management
units also requires fundamental changes in institutional set up to govern and manage water in the polders.
• The present set up is too fragmented and disjoint– BWDB is in charge of embankment and sluices– BADC for small scale irrigation systems in/out-side polders– LGED for structures outside the polders
• There should be one single entity in charge of each whole polder, servicing the people living within the polder and their production systems.
Key messages for policy makers
• Invest in polder water management• Consider polder as a single integrated
water management unit servicing the production systems
• Create small water management units with provision of drainage and water storage
• One single entity in charge of each whole polder
Thank You
Adoption of improved technologies improved spatial data availability
Why do we need improved spatial data?
The challenge is to identify where and when each improved technology can be successful in the coastal polder zone Technology targetting
The coastal zone is complex, it faces multiple challenges, and situations change quickly over small distances and from season to season A high resolution spatial database and multidisciplinary partnerships are paramount for targetting at village level.
1/12
Study sites for improved technologies
Polder 3Rice/Aquaculture &
Shrimp/Shrimp
Polder 30Intensification from
one to two crops
Polder 43/2fIntensification from
one/two to three crops
2/12
Increasing area affected by soil salinity
Soil salinityNoneVery slightSlightStrongVery strong
3/12
Large changes in salinity through the year
Movement of the 4ppt water salinity boundary in early 2011
4/12
Improving livelihoods and profitability
Current practice – shrimp farming in Feb-Jun
5/12
Rice Shrimp
Upper threshold limit of salinity - Rice
Date
Wate
r sa
linit
y (
ppt)
Lower threshold limit of salinity - Shrimp
Daily water salinity
Opportunities for targetting additional crop in fallow lands (Polder 3)
Opportunity for rice Aug-Nov and shrimp Feb-Jun
Spatial land use patterns are complex!
There is scope for intensification & diversification in the coastal zone
Boro riceNov – Apr
5m hectares
Aus riceApr – Jul
1.1m hectares
Aman riceJul – Nov
5.8m hectares
6/12
Cropping systems are complex!
Detailed data & multi disciplinary expertise needed to define requirements
7/12
Aman - Boro Water quality and availability in dry season
Description of Land use type(technology)
Fresh (< 4dS/m),
ground water availability
and pumping depth
Month when river water still
remain fresh
(<4 dS/m)
Internal storage
capacity in relation to land area(ML/ha)
Proximity to river, canal,
ponds (m)
Difference (m) in high water level in Mar and
land surface for
gravity irrigation
(m)
Aman HYV rice is transplanted in July-August, to be harvested by the end of November (Moderate Salinity zone) or December (low saline zone).
Yes, < 6 m
S1 March S1 > 5 S1 <50 S1 > 1 S1
Yes, 7 -20 m
S2 Feb S2 2.5 - 5 S2 50-100 S2 0.5 - 1 S2
yes, > 20 S3 Jan S3 1 - 2.5 S3100-300
S30.2 - 0.5
S3
No SN Dec SN <1 SN >300SN
< 0.2 SN
Aman - Boro Water quality and availability in wet season
Description of Land use type(technology)
Maximum inundation depth (m) in August
Maximum inundation depth (m) for more than one week in
Sep/Oct
Difference (m) in land surface and low water level in
Sep/Oct for drainage
Boro rice is seeded around 15 Nov. (MS) to 15 Dec (LS). Boro rice is irrigated with river water (when fresh) or with water stored in canal networks
< 0.1 S1 < 0.2 S1 > 1 S1
0.1 – 0.2 S2 0.2 – 0.5 S2 0.5 - 1 S2
0.2 – 0.3 S3 0.5 – 0.8 S3 0.2 – 0.5 S3
> 0.3 SN > 0.8 SN < 0.2 SN
S1 = Most Suitable S2 = Suitable S3 = Least Suitable SN = Not Suitable
Cropping systems are complex
Fresh GW (< 4dS/m)
Tubewell?Depth of prehatic
surface (m)
Month when river water (< 3
dS/m)
Storage capacity (ML/ha)
Proximity to fresh SW source (m)
Suitability for dry
season rice crop
Yes
No
Shallow
Deep
< 6
7 - 20
Mar
Feb
Jan
Dec
> 20
2.5 - 5
1- 2.5
2.5 - 5
1 – 2.5
< 100
> 100
< 100
> 100
< 100
> 100
< 100
> 100
S1
S1
S2
S3
S1
S1
S2
S2
S3
S2
S3
S3
SN
SN
Groundwater Surface water
8/12
Coastal ecosystems are complex!
Social
Demographic
Economic
Infrastructure
Water
Climate
Soil
Land cover
Topography
Open sharing of GIS data and expertise across institutes in Bangladesh
9/12
BWDB
IRRI
IWM
LGED
SRDI
Basin partners
Data held by many different institutes10/12
We need a coordinated approach to facilitate data sharing/access
Detailed and specific information is needed
Incorporating socio economic constraints to the usual “climate+soils+topography” approach is paramount for realistic suitability maps
11/12
Location and time specific constraints like appropriate sluice gate operation (community level water management), and canal siltation (infrastructure maintenance), need to be incorporated into the suitability analysis as critical requirements for innovative cropping systems.
Key messages on spatial data12/12
A framework that encourages institutes in Bangladesh to openly share GIS data in consistent standards will greatly
enhance the ability to respond to policy makers needs A Spatial Data Infrastructure (SDI) for Bangladesh
Socioeconomic, infrastructure and management information need to included in the targetting approach. They are as important as biophysical constraints.
Thank you
Adoption of improved technologies requires better investments in water
management
Some policy suggestions
We studied institutional arrangements in 5 BWDB polders and 4 LGED sub-projects
To understand the actors, communities and institutions
What are the problems and for
which groups? How are they managed?
Which institutions, organizations and
individuals are involved in water
management? How?
How is the community involved
in water management?
POLICY CHANGE FOR BETTER WATER MANAGEMENT
Over 3000 people were interviewed
Polders and sub-projects vary widely
– Salinity and fresh water availability
– Cropping systems and livelihoods
– Procedures for closing and opening of gates
– Role of Water Management Organizations
Diverse cropping pattern depending on salinity levels
Institutional Arrangements of Water Management varies across and within polders (e.g. who opens gates?)
Polder/Sub-Project
WMO Gher owners
UP Chairman and Members
Gate committee appointed by UP or BWDB
Local elites
Polder 3 - × × × ×
Polder 31 × × × × ×
Polder 30 × - × - ×
Polder 43-2F × - × - ×
Latabunia × × - - ×
Jabusha × × × -
Jainkathi - - × - ×
Bagarchra × × × - ×
But all sites have three things in common
• Poor condition of embankments, khals and gates due to poor maintenance
• Conflicts surrounding water management and land use
• UP Chairman and Members are de-facto decision makers, but do not necessarily have a formal role
Why are water infrastructures not maintained?
• WMOs were created for solving ‘deferred maintenance’
• Why communities don’t maintain?– Public goods dilemma
– Even so called ‘minor’ repair and maintenance may be beyond the capacity of communities
– Incentive problems: if communities don’t fix it in time, government or donor will in a few years time
‘Deferred maintenance’ as an incentive problem• Why can’t the governments
do regular repair and maintenance?
– Allocation from Non-Revenue Development Budget is less than 10% of total requirement
– Belongs to communities, they must do it
• Why don’t donors pitch in?– Belongs to GOB and
communities, they must do it
Field evidence shows communities
cannot do maintenance
expected of them.
How can we help communities to better maintenance?
• Give WMOs access to income generating assets like lease of common land or micro-credit
• Devise fair rules for collection of maintenance funds
• Coordination between existing WMOs and UP
But communities can not do it alone!
Solutions beyond community levels• Use existing social safety
net funds of UP, like 40 days work, KABHIKA for polder maintenance
• Twin benefits of employment creation (LCS) and infrastructure maintenance
• Coordination between UP, BWDB, LGED and Central Government
Solutions by donors and central government
• Create of Donor-Government Trust Fund for Maintenance of Water related infrastructure in Bangladesh
• All polder/sub-projects get allocations for repair and maintenance every year from interest amount of Trust Fund
GoB
Development partner
Donor Government Trust Fund
Trust fund money is allocated to every polder each year for Repair and Maintenance
How to reduce drainage problems and conflicts?
Divide polders into smaller hydrological units (SHU).
Use LGED rural roads as hydrological boundaries
For even smaller boundaries, use UP social safety funds for ail construction
Some of these are already happening…
• Constitution of Union Parishad Coordination (UPCC) launched under Local Government Support Project to oversee all developmental activities.
• Using rural roads as hydrological boundaries for forming smaller hydrological units. LGED is already doing it in SSWDRP III and IV phases
• Delineating smaller hydrological units within BWDB polder with help of LGED: Already happening in Narail Chenchury Bil project where LGED is doing 30 sub-projects within BWDB polder
So, what can policy makers do? Devise better ways of maintaining existing infrastructure:
– Through Donor-Government Joint Maintenance Trust Fund
– Use social safety net programs for construction of rural roads, small ails, and repair of internal canals and embankments
Devise ways to reduce water conflicts:
– Divide larger polders into smaller hydrological units by using rural roads and ails as hydrological boundaries
– Formal involvement of UP’s and WMOs
So, what can policy makers do?
Thank you