Presentation of Larry Harrington, Ganges Basin, as part of the "Simposio Internacional: El Desafío del Agua y la Alimentación en el Mundo" organized by National Authority of Water (ANA) in Peru and the Consorcio para el Desarrollo Sostenible de la Ecorregión Andina (CONDESAN). June 3, 2013.
Master Plan Project Report on Remodeling of Storm Water Drains_BBMP
Similar to The Ganges Basin Development Challenge: Increasing the resilience of agricultural and aquaculture systems in the coastal areas of the Ganges Delta
Similar to The Ganges Basin Development Challenge: Increasing the resilience of agricultural and aquaculture systems in the coastal areas of the Ganges Delta (20)
The Ganges Basin Development Challenge: Increasing the resilience of agricultural and aquaculture systems in the coastal areas of the Ganges Delta
1. The Ganges Basin Development
Challenge (GBDC)
Increasing the resilience of agricultural
and aquaculture systems in the coastal
areas of the Ganges Delta
2. Andes • Ganges • Limpopo • Mekong • Nile • Volta
Water for a food-secure world
The short, short version
• Coastal Bangladesh, seasonal salinity, “polders”
• Low productivity farm systems
• Enormous potential to intensify systems if better water control
• But infrastructure for water control needs improvement
• Multiple institutions working on water infrastructure –
coordination problems
• CPWF projects working with National Planning Commission and
other local institutions on practical steps to upgrade infrastructure
– could involve up to USD1b of investment
3. Andes • Ganges • Limpopo • Mekong • Nile • Volta
Water for a food-secure world
LOCATION OF GANGES RIVER BASIN
5. West Bengal, India
South West Bangladesh
Patuakhali STU
Polder 43/2/F
Polder 30
Polder 3
North 24 Parganas
South 24 Parganas
Andy Nelson
“LOW SALINITY”
•Water “stagnation” 30-50 cm
several weeks in aman
•River water fresh 10-11 months
•Mild soil salinity in dry season
“MEDIUM SALINITY”
•Water “stagnation” 30-50 cm
several weeks in aman
•River water saline mid-Feb-Jun
•Medium soil salinity in dry
season
“HIGH SALINITY”
•Water “stagnation” 30-50 cm
several weeks in aman
•River water saline Dec-Jul
•High soil salinity in dry
season
6. Increasing area affected by soil salinity
Soil salinity
None
Very slight
Slight
Strong
Very strong
3/12
7. Study sites for improved technologies
Polder 3
Rice/Aquaculture &
Shrimp/Shrimp
Polder 30
Intensification from one to
two crops
Polder 43/2f
Intensification from
one/two to three crops
2/12
8. 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
Low salinity areas: Aus-Aman-Rabi Cropping System
9. 15 July
15 Nov 30 Apr
Rabi (120-140 d)
Dec/Jan
Aman (140 d)
M J J A S O N D J F M A M
Terminal Drainage
Moderate salinity areas: Aman-Rabi Cropping System
10. Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Wet seasonDry season
Gher
preparation
Seedling
Bagda Rice+Fish
High salinity areas: Improved aquaculture-rice
Drain out saline water,
expose gher soil to
rainfall to leach down
soil salinity
Poorly-drained gher in polder 3 Well-drained gher
12. • 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.
Details: What “water control” means in this case
13. Re-defining the roles of polders
• Each polder needs to be considered as an
integrated water management unit
• The original role of the polders was to enable one
crop of tall, long duration traditional aman rice
• HYVs & improved cropping system technologies
now available, but require better water control
14. 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
15. 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
16. 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
17. 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
18. 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
19. Trust fund money is allocated to every polder
each year for Repair and Maintenance
20. Polder 31
Polder 30
River
Inlet to sluice gate
Sluice gate on river side
Sluice gate inside the
polder
5 research projects - expected outcomes
Use of suitability domain maps as a decision
support tools
Develop, evaluate, and adapt new and improved
cropping and aquaculture systems
Better polder governance through reduced conflict
between fishermen and farmers
Understanding of the key external drivers of change
in water resources
Establish a policy framework for scaling up/out of
technologies to enable changes in HH of Ganges
coastal zone (team effort)
Polders in the southern region on Bangladesh and India were built in the 60’s and 70’s to control storm surges and create freshwater flood plains. 2-3 crops a year, however…………..There are no polders in W.Bengal (India). The polders were built to prevent flooding at high tide during the rainy season, and to prevent saline water intrusion during the dry season. In most of the polders of SW Bangladesh there is only 1 rice crop per year (aman, grown during the rainy season). Farmers grow a low yielding, tall traditional variety, sometimes followed by a low yielding legume. In the polders in the more saline areas, aman rice is sometimes grown in rotation with brackish water shrimp, which is a risky practice, but can be highly profitable. However, because of poor management of the shrimp ghers, farmers are currently unable to grow aman rice in many locations.
Working in 4 locations in Bangladesh & 2 in India representing 3 situations
Structured into 5 inter-related projects addressing the single challenge