Final Volta Basin Development Challenge Science Workshop, September 2013

1. IMPACTS OF AGRICULTURAL WATER MANAGEMENT
INTERVENTIONS ON THE HYDROLOGY OF THE WHITE
VOLTA RIVER BASIN: THE CASE OF DAMS AND
DUGOUTS.
Joachim A. Abungba1, Samuel N. Odai1 , Frank O. Annor1,2, 3Maxwell Boateng-Gyimah and
Geoffrey Anornu1
Abstract
The reduction of flows into the White Volta is not only due to evaporation but also
other factors such as continuous development of reservoirs and dugouts, although
some of these reservoirs have problems with construction and boring of dam walls
by crocodiles which leads to seepage. Results show a significant reduction in flow
between 2017 and 2028 and beyond 2031. Specific irrigation schemes like Tono and
Vea will record the highest unmet demand of about 0.00045Mm3 between 2038
and 2039. More reservoir development should be coordinated and targeted at
improving the existing ones before any new development.
Conclusions
Small reservoirs are a major component of the people’s
farming activities with over 239 of such reservoirs dotted
across the length and breadth of the region.
About eighty-five percent (85%) of reservoirs from the
study are in good condition and are therefore supporting
agricultural production through dry season irrigation in the
area.
Both Tono irrigation scheme in the Nawuni catchment will
be hard hit in terms of unmet water demands especially from
the year 2032 to 2040.
Pictures
CGIAR Challenge Program
on Water and Food
P.O. Box 2075,127 Sunil Mawatha
Pelawatta, Battaramulla, Sri Lanka
T: +94 11 288 0143
F: +94 11 278 4083
E: cpwfsecretariat@cgiar.org
www.cgiar.org www.waterandfood.org
1 Civil Engineering Department
Kwame Nkrumah University of Science and Technology
Kumasi, Ghana
September 2013
Background and Purpose
Agriculture is the main economic activity in the White Volta River Basin
with agricultural water management activities contributing significantly to
food security and income.
Current situation: Agricultural water management practices such as the use
of shallow wells with buckets/ water pumps, dugouts, small reservoirs with
lined or earth canals, stone and earth bunds and water pumps in rivers and
wells in river beds have become a growing phenomenon in the Basin
(Laube et al., 2008).
Uncertainty: Unfortunately no long-term data and projections on the
impacts of further development of agricultural water levels are available
(Martin and Van de Giesen, 2005).
Main objective of our research is, to assess the Impacts of Agricultural
Water Interventions on the Hydrology of the White Volta River Basin.
Findings
About CPWF
The CGIAR Challenge Program on Water and Food was launched in 2002. CPWF aims to increase the resilience of social and
ecological systems through better water management for food production (crops, fisheries and livestock). CPWF currently works in six
river basins globally: Andes, Ganges, Limpopo, Mekong, Nile and Volta.
CPWF is a member of the CGIAR Water, Land and Ecosystems Research Program. The program focuses on the three critical issues
of water scarcity, land degradation and ecosystem services, as well as sustainable natural resource management. CGIAR is a global
agriculture research partnership for a food secure future. Its science is carried out by the 15 research centers who are members of the
CGIAR Consortium in collaboration with hundreds of partner organizations.
Methodology
Kwame Nkrumah University
of Science
and Technology, Ghana
Desk Study
Field Measurements of
Reservoirs, Communities and institutional
interactions.
Calibration and Validation of the Model (WEAP)
Application of Calibrated model and Analysis
Report
Measurement of reservoirs
Model - impacts of AWMI
Evaluate the state
of Small Reservoirs
N
i
aveobsiobs
N
i
iestiobs
QQ
QQ
1
2
..
1
2
..
)(
)(
1
SR area Measurements
District No. of SR Total Area (Ha)
Bolgatanga & Talensi Nabdam 30 205.94
Kasena/ Nankana East & West 81 2277.35
Bawku West 17 187.65
Bawku Municipal, Binduri &
Garu
67 632.94
Builsa 27 149.76
Bongo 17 549.2
TOTAL 239 4002.84
State of Small Reservoirs
(Very good & Good- no seepage, no trees,
less siltation); Fair- very poor (serious
seepage, siltation, presence of trees)
0
10
20
30
40
Very good Good Fair Poor Very Poor
N
u
m
b
e
r
o
f
S
R
(
s
)
Condition
Presence of trees on reservoir wall
Silted reservoir
Surface water Availability
Reference
Streamflow (below node or reach listed)
Year: 2010, All months (12), River: White Volta River
3WithdrawalNode2
13WithdrawalNode10
31RedVoltaRiverInflow
39SissiliRiverInflow
43NawuniGS
BillionCubicMeter
11.0
10.0
9.0
8.0
7.0
6.0
5.0
4.0
3.0
2.0
1.0
0.0
Mean runoff in
the White Volta
is estimated at
11.5 billion m3
Very good reservoir
Pre and Post Impact of Reservoirs (Pwalugu)
0
50
100
150
200
250
300
350
400
1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 2015
Streamflow(cums)
Year
August
Unmet water demands
Kwame Nkrumah
University of Science
and Technology, Ghana
Specific Catchment
Water Availability
Acknowledgement
The author wish to thank the V1 project of the Challenge Program on
Water and Food (CPWF) for the support with funds for the studies and
fieldwork. Special thanks goes to Dr. Jennie Baron of SEI for her support.
Upper East Region
Country boundary
White Volta Sub-basins
Volta Sub-basins
2 Faculty of Civil Engineering and Geosciences
Water Resources Section
Delft University of Technology, Delft, Netherlands
3 Water Resources Commission
Accra, Ghana
Contact: joachimayiiwe@yahoo.com