Assessment of Water Balance in the Ilauko Reservoir of the Ouémé at Savè Catchment (Benin, West Africa)

Abstract

This study deals with the management of the Ilauko reservoir of the SUCOBÉ SA Company, well known as the "Society Sucrière of Savè" (SSS), which is located in the Oueme at Save catchment. The objective of this paper is to assess the water balance in this reservoir. A better knowledge of this water balance will allow reducing, in the short, medium and long term, water shortages due to climate change. It will also allow facing the water needs of the populations. The water balance was used as an approach to estimate the water input to the watershed. Its application derives from the conservation principle of water volumes. The results show that on Ilauko reservoir, the inflows are greater than the outflows. Thus, the annual variation of the volumes in the reservoir that are obtained in 2012 and 2013 are positive and are respectively 2,179,215 m3 and 598,452 m 3 . By this fact, there are less of anthropic activities that are exerted on the reservoir during these periods. Furthermore, it was noted that, on the Ilauko dam, 68% of the water volumes are evaporated, 0.5% are infiltrated and 32% are withdrawn to face the irrigation needs and drinking water supply of Savè town and its surroundings.