This was presented at the Basin Focal Project Review meeting held in Cali, Colombia from 1-5 Feb, 2008

1. Volta b i 2030
V lt basin 2030:
Needs,
opportunities
and risks"
Cali February 2008

2. Volta Basin
area : 395 000 km2
Burkina Faso
Population (2007)
20 M
Ghana Data mainly from
Ghana and
Burkina Faso
Faso,
The Volta basin : 6 countries
Cali February 2008

3. Within basin Dissemination pathway
Go e
Government :
e t Outside the basin
Relevant
Ministries, BFP Volta Scientific
Departments community
and Agencies
CPWF
(MDA)
Institutions for
District
Di t i t water management
assemblies at basin scale
Donors
Traditional VBA bilateral,
bilateral
Heads (Chiefs) international
ECOWAS-WRCU
Development
agencies WRC x 6 NGOs
Farmers/Water VRA Ghana
users
associations
Cali February 2008

4. Water
Water productivity
Water and poverty
Poverty
P t Food
production
Institutions
Scale : the basin time : present and trends 2050
Cali February 2008

5. The challenge (1)
Volta Pop. Starchy food Starchy food
basin ( x106) produced needed
(kcal x 1012) (kcal x 1012)
Year
2005 19.5 21* 17
2025 32 ? 28
2050 50 - 60 ?? 48
plus possible climate change impact
Cali February 2008

6. The challenge (2)
The Global scenarios for SSA to 2050 (SRES and
Millennium Assessment ) :
• the demand will not be matched by an increase in
domestic agriculture p
g production,
,
although
• higher levels of agriculture productivity growth
compared with north western regions,
• the relatively lower level of productivity from which
SSA region is starting explains much of this difference.
i i t ti l i h f thi diff
Cali February 2008

7. Two main priorities
The rain fed food crops in the semi-arid area
The water uses in the basin
Cali February 2008

8. The rain fed food crops in the semi-arid area
p
present distribution
yields
water productivity
rural poverty
l t in f d
i food crop production
d ti
in fisheries
in livestock production
p
the ways out of poverty:
diversification (small scale irrigation ..)
)
intensification (...)
Cali February 2008

9. Food production
Rain fed = 99 % of
total cultivated area
Main cropping systems
Cereals
millet
sorghum
maize
rice
Rootcrops
yam
cassava
plantain
( data from MOFA and
MAHRH)
Cali February 2008

10. The
Th agroclimatic zones
li i
and rainfall
-Sahel
-Sahelo-sudan
Sahelo sudan
-Sudan
-Guinean
Cali February 2008

11. 500 - 900 mm 900 - 1100 mm > 1100 mm
% of cultivated area for the different crops along the
Cali February 2008
climatic gradient

12. The increase in production results from increase in cultivated area,
not from increase in productivity.
p y
Data for the Ghana and Burkina parts of the basin, 1992-2004.
Cali February 2008

13. The cropped area
as % of total land
Cali February 2008

14. 2,5
Y Maize (t/ha)
2
1,5
15
1
0,5
0 Rainfall (mm)
400 900 1400
Production data from Ghana and Burkina Faso, 1990-2002,
rainfall from CRU
Cali February 2008

15. 0,4
WPr maize kg/m3
0,3
0,2
02
0,1
,
0,0 Rainfall (mm)
400 900 1400
Cali February 2008

16. 2,5
Y millet t/ha
2
1,5
1
0,5
Rainfall (mm)
0
400 600 800 1000 1200 1400 1600 1800
Cali February 2008

17. 0,4
04
WPr millet kg/m3
0,3
0,2
0,1
0 Rainfall (mm)
400 900 1400 1900
Cali February 2008

18. An analysis of rural p
y poverty in Burkina Faso
y
data from TASIM-AO project
3 regions,
6 villages in each
30 households in each
The study was based on the food sales from the
Households in order to evaluate the inland market
possibilities
The results are by quartiles of the total, plus the upper
decile
Cali February 2008

19. Poverty incidence
in Ghana
Burkina Faso
and Togo
Cali February 2008

20. Cumulated cultivated area as a function of the household
sales.
The three lower deciles cultivate 10 % of the land, while the
upper d il cultivates 30 % of the land
decile l i f h l d
Cali February 2008

21. From Q1-Q2 to Q3-Q4
Total sales +++
area +++
Water/irrig ++
Family manpower ++
Family manpower/ha --
Hired manpower days/ha +++
Inorg. fertilizer % ++
Draught power % ++
Draught power number ++
Cattle +++
Small ruminants ++
Credit use % +
Family credit % ++
Institutional credit % +
Cali February 2008

22. 2 Total sales ( CFA )
1,6
3000 USD
1,2
12
Fada
2000 USD Kaya
0,8 Dédougou
0,4 1000 USD
area (ha)
( )
0
0 5 10 15 20
Cali February 2008

23. InorgFertilizer(% of farms)= f(ha)
100
75
Fada
50 Kaya
Dédougou
25
ha
h
0
0 5 10 15 20
Cali February 2008

24. The main constraints to the increase of production for
food sales (from TASIM-AO, 2005

25. PN5 experiments Northern Ghana
1800
1600
1400
1200
g/ha
No fertil.
1000
Yield kg
Micro-dose
800
Full dose
600
400
200
0
Maize Millet Sorghum
Effects of fertilizer on crop yields central Volta basin
yields,
(from CPWF PN5)
Cali February 2008

26. Modeling f tili
M d li fertilizer impact on yields
i t i ld
and water productivity
Cali February 2008

27. Out of poverty
Household water develop affordable access to good
d l ff d bl t d
quality (health etc.)
Intensification = better use of rainfall
Increase power, tools, land, yield, decrease vulnerability
draught animals, plough or cart,
g ,p g ,
fertilizers, SWC, rain harvesting (PN47)
Diversification
small scale irrigation (dry season),
large scale irrigation
g g
cash crop,
small ruminants, cattle,
processing ( fish, beer ...),
fishing ><cultivation
Cali February 2008

28. Lack of access to
good quality
household water
The two darker
zones are f more
for
than 60 % without
good access
Cali February 2008

29. Water related diseases : a significant limiting factor
The example of malaria
High prevalence o e whole bas ,
g p e a e ce over o e basin,
Health system very expensive and poor efficiency
Prevention not affordable ( > 1 USD/day)
Malaria as cause of 30 % of micro credit failure
(Planet Finance), and concern at macro economic state scale
Technical solutions exist (ACT, mosquito net, maternal
prevention) but poorly applied.
Cali February 2008

30. Basin wide malaria
prevalence model
(
(from MARA/ARMA
Program)
From environment,
pop density, rainy
density
season,...)
10% classes
To be compared with
cultivated area %
Cali February 2008 Volta BFP

31. Three main activities
Cultivation Livestock Fisheries
Similar status for the poorer : lack of production
means and poor labour efficiency
Fisheries
Social and economic importance of fisheries for the
basin
Livestock
Small
S ll ruminants as safety net for many,
i t f t tf
Intensification needed, with improved use of fodder
Present and future export value.
p
Cali February 2008

32. Out of poverty
Intensification ( = better water productivity)
Small farmer
fisherman
Incentives and credit as f cotton development
for
= political will
With nation wide benefits for the people now and
later
- Large inland market,
- land tenure, market access, inland market development,
Cali February 2008

33. Water productivity
The general approach, at the field scale,
WP = production/water consumed by the plants
Grain , biomass Soil evaporation + evapotranspiration
In rain fed agriculture, the agro-climatic regions
determine where specific crops can be grown. The
p p g
field needs a certain amount of rainfall.
With a farmer or ecological perspective, rainfall WP
is chosen as a tool to measure improvement of a
system (Gregory 1988 in Rockström & Barron 2007).
WPr
WP = production/ rainfall received by the field
d ti / i f ll i d b th fi ld
Cali February 2008

34. Water uses in the basin
The surface water resource
The underground water
Surface water allocation
Opportunities:
irrigation, small scale
irrigation, large scale
i i ti l l
hydropower
Volta basin Authority
Risks : climate change
environmental flows
Simulation : two scales
• whole basin and Lake Volta
• sub-basin and small reservoirs ( need for recent
b b i d ll i df t
data)
Cali February 2008

35. Where does
the water go ?
Mostly in the air,
Runoff coef. (3 -12 %)
Cultivated area
= (13.7 % of total)
= most of evap. not from cultures
Irrigation
< 0.1 % of total area
Underground
xx
Cali February 2008

36. Many of the rivers of the
Upper Volta basin used to
dry up during part of the year
before 1974.
Some have become perennial
after the construction of hydro-
electric reservoirs.
Data from Moniod et al. 1977
Cali February 2008

37. Lake Volta :
a major component of
the aquatic system
8500 km2,
about 140 km3 (three years
residence time),
and uncertainty about
y
the fisheries production Ghana Togo
Circa 70 000 fishermen
Fishing = diversification
from MODIS data base
Cali February 2008 Volta BFP

38. nflow to Lake Volta (km3) Observed inflows to Lake Volta (1985-99)
70
60
50
40
30 y = 0 36x - 107
0,36x
L
20 R2 = 0,66
10
0
In
200 250 300 350 400 450 500
Rainfall on basin (km3)
Observed inflows to Lake Volta as a function of annual rainfall
on the basin. Data from Volta River Authority and CRU.
Mean inflow : 36.7 km3/y Mean runoff coef : 9.3 %
10% change in rainfall = 39 % change in inflows
Cali February 2008

39. Two questions
q
• What would be the impact of rainfall change on the
availability of water for electricity p
y y production ?
• What relationship between small reservoirs
development and water inflows to Lake Volta ?
The approach :
A simulation combining river discharge
(
(from Mac Kirby) and WEAP for water uses and
y)
allocation
Cali February 2008

40. Plus 1 °
ITCZ latitudinal shift
and
d
rainfall changes
Minus 1°
1980-2000
Our climate change scenario
Cali February 2008

41. Domestic 156
Livestock 71
Irrig. various 242
Large dams 630
Small reservoirs 894
Lake Volta 35000
Basin wide main water uses 1996-2000
uses,
Cali February 2008

42. Akosombo dam and spillway. In March 2007 only 2 of
spillway 2007,
the 6 turbines were working, and only one in June
Cali February 2008

43. 60 000 Reference
scenario
50 000 Wetter scenario
40 000 Drier scenario
30 000
20 000
10 000
0
0 2 4 6 8 10 12 14 16 18 20 22
Year of simulation
Inflows to Akosombo as simulated by WEAP in the three scenarios.
The main variability remains dependent on the year to year rainfall
variations.
Cali February 2008

44. 160 000
Storage capacity (148,000 Mm3)
140 000
120 000
m3)
100 000
Storage (Mm
80 000
Top of inactive (70,000 Mm3)
60 000
S
Top of buffer zone (85,000 Mm3) Reference scenario
40 000
Wetter scenario
20 000
Drier
D i scenario
i
0
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
Year of simulation
But on the long term, there is a progressive increase or
decrease in water availability
Cali February 2008

45. Small reservoirs development ( see also PN47)
There is a strong demand for new small reservoirs
ne reser oirs
Present total storage in 2007 is estimated from our
calculations as 900 Mm3 for 1600 reservoirs.
reservoirs
The
Th model needs more recent data for the northern basin,
d l d d f h h b i
because of the hydrological paradox :
In dry periods ( post 1972) the runoff coefficient has
almost doubled compared with the wetter period (pre 1972)
in the basin with a rainfall below 750 mm/y. In Wayen, the
coefficient changed from 1.4 to 2.8
Another approach indicates that the volume of the
reservoirs is substracted f
i i b t t d from th fl
the flow to Lake Volta.
t L k V lt
Cali February 2008

46. Outputs of BFP Volta
Portofolio of research and development activities for VBA,
UCRE, funding agencies, NGOs and technical ministries :
- underground water resource,
- institutions changes for land tenure, investment
- livestock (transhumant) status enforcement,
( )
- bush fodder,
- weather forecast (AMMA) and practical use,
- fisheries monitoring (how) and improvement,
- further developments of allocation model within
climate and population change, at different scales,
addressing local and transboundary issues,
More on social acceptance/enforcement
Ouagadougou November 2007

47. Water availability:
Climate change (past and future),
Rain season variability and forecast,
forecast
Surface/underground resource and variations
as a f
function of land cover and land use,
ti fl d dl d
Impact of reservoirs on the water availability
p y
and transnational agreements
Water budget
budget.
Socio-economic analysis of hydropower generation
compared with other water uses.
d ith th t
Ouagadougou November 2007

48. Agriculture :
- soil and water conservation techniques *
(cost in labour, e.g. zaï only on most degraded soil and
high pop density, 1.5 % of cultivated area),
- f tili
fertilizer use, socioeconomic
i i
- groundwater use
- irrigation potential
Development of small reservoirs for small irrigation
irrigation.
Social management of large schemes
Water
W t quality as a result of pesticides..
lit lt f ti id
Ouagadougou November 2007

49. Volta basin institutions (1)
Dual
D l system with
t ith
Legal state
g and traditional hierarchy
y
low enforcement power land tenure and
water access
conflicts use one against the other
Progressive shift from one land tenure to the other ??
P i hift f l dt t th th
= the poor maintained poor
insecure land tenure, small investment on water and soil
conservation techniques or fertilizers
Ouagadougou November 2007

50. Volta basin institutions (2)
Health system to be improved, by capacity building and
public awareness,
Basin scale Volta basin Authority being created, and WEAP for water
allocation between power generation and irrigation
Market access, for cash crops (eg cotton) and meat, and in-basin
market development for food crops.
Ouagadougou November 2007

51. Within basin Dissemination pathway
Go e
Government :
e t Outside the basin
Relevant
Ministries, BFP Volta Scientific
Departments community
and Agencies
CPWF
(MDA)
District
Di t i t meetings
assemblies
Donors
Traditional VBA bilateral,
bilateral
Heads (Chiefs) international
ECOWAS-WRCU
Development
agencies WRC x 6 NGOs
Farmers/Water VRA Ghana
users
associations
Cali February 2008

52. Thank you
Cali February 2008

53. The uneven distribution of
towns and population density
in Ghana and Burkina Faso
Cali February 2008

54. Rural Poverty
y
Why
Water related
Poor water productivity (yields)
Rain fed dominance, rainfall quantity and variability risk
avoidance low yields
health (malaria), domestic water (
( ) (diarrhea)) human power
decreased low yields
access to water for livestock conflicts
Non water related
Poor soils, degraded soils,
Low work power
Institutional,
Land tenure, access to water, micro credit not for agriculture,
tenure water agriculture
cash crop market low (cotton), access to fertilizers,
Why?
Solutions and techniques available but lack of implementation
Cali February 2008