HR: 1340h
AN: H23B-1426 [Abstracts]
TI: Predicting the downstream impact of ensembles of small reservoirs with special reference to the Volta
Basin, West Africa
AU: * van de Giesen, N
EM: n.c.vandegiesen@citg.tudelft.nl
AF: Delft University of Technology
Water Resources Management, Stevinweg 1, Delft, 2628 CN
Netherlands
AU: * van de Giesen, N
EM: n.c.vandegiesen@citg.tudelft.nl
AF: Center for Development Research (ZEF)
Bonn University, Walter-Flex-Str 3, Bonn, 53113
Germany
AU: Andreini, M
EM: m.andreini@cgiar.org
AF: International Water Management Institute, PMB CT 112
Cantonments, Accra, NA
Ghana
AU: Liebe, J
EM: jrl58@cornell.edu
AF: Cornell University
Biological & Environmental Eng, Riley-Robb Hall, Ithaca, NY 14853
United States
AU: Liebe, J
EM: jrl58@cornell.edu
AF: Center for Development Research (ZEF)
Bonn University, Walter-Flex-Str 3, Bonn, 53113
Germany
AU: Steenhuis, T
EM: tss1@cornell.edu
AF: Cornell University
Biological & Environmental Eng, Riley-Robb Hall, Ithaca, NY 14853
United States
AU: Huber-Lee, A
EM: ahuberlee@tellus.org
AF: SEI-Boston, 11 Arlington Street, Boston, MA 02116-3411, USA, Boston, MA 02116
United States
AB:
After a strong reduction in investments in water infrastructure in Sub-Saharan Africa, we now see a revival and increased
interest to start water-related projects. The global political willingness to work towards the UN millennium goals are an
important driver behind this recent development. Large scale irrigation projects, such as were constructed at tremendous
costs in the 1970's and early 1980's, are no longer seen as the way forward. Instead, the construction of a large number of
small, village-level irrigation schemes is thought to be a more effective way to improve food production. Such small schemes
would fit better in existing and functioning governance structures. An important question now becomes what the cumulative
(downstream) impact is of a large number of small irrigation projects, especially when they threaten to deplete transboundary
water resources.
The Volta Basin in West Africa is a transboundary river catchment, divided over six countries. Of these six countries,
upstream Burkina Faso and downstream Ghana are the most important and cover 43% and 42% of the basin, respectively. In
Burkina Faso (and also North Ghana), small reservoirs and associated irrigation schemes are already an important means to
improve the livelihoods of the rural population. In fact, over two thousand such schemes have already been constructed in
Burkina Faso and further construction is to be expected in the light of the UN millennium goals. The cumulative impact of
these schemes would affect the Akosombo Reservoir, one of the largest manmade lakes in the world and an important motor
behind the economic development in (South) Ghana.
This presentation will put forward an analytical framework that allows for the impact assessment of (large) ensembles of
small reservoirs. It will be shown that despite their relatively low water use efficiencies, the overall impact remains low
compared to the impact of large dams. The tools developed can be used in similar settings elsewhere in the developing world.
The methods are mainly based on relatively objective observations as provided by satellites. As such, these tool provide a
good basis for transboundary impact assessment and conflict avoidance.
UR: http://www.smallreservoirs.org
DE: 1803 Anthropogenic effects (4802, 4902)
DE: 1804 Catchment
DE: 1834 Human impacts
DE: 1842 Irrigation
DE: 1880 Water management (6334)
SC: Hydrology [H]
MN: Fall Meeting 2005