The annual flooding of the Inner Niger Delta is the key driver that governs the ecology, livelihoods and ecosystem services of the area. Every year a vast area is being inundated by the annual floods. In the rainy season the Niger River and its tributaries are filled by the rains in the Guinean highlands, before flowing eastwards towards Mali. This means that any interventions upstream, hydropower, irrigation or other use (see hydrological infrastructure), have major impacts on the discharges in the rivers and hence, the flood patterns of the Inner Niger Delta. Several studies have been carried out to investigate the impacts of such interventions on the flood patterns and ecosystem services in the Delta. [links to reports] Based on the results of these studies, a simplified online tool called Decidaid has been developed that shows these impacts in maps and graphs.
The user can select a key parameters that reflect the realization of the Moussako (or Fomi) dam and the expansion of Office du Niger. Based on these choices, the maps showing inundated area and the graphs showing ecosystem services are automatically updated to show the impacts of these choices. To see how the Decidaid tool works, please make your selection in the dropdown menus and have a look at the maps and graphs below.
More details on the impacts of water management in the Upper Niger Basin can be found in several background documents: