Analysis of hydrological dynamics and hydropower generation in a West African anthropized watershed in a context of climate change

This study was conducted in the Bandama watershed (BW) in Côte d’Ivoire (West Africa). The objective is to analyze hydrological dynamics and hydropower generation in BW in a context of climate change. The methodology is based on the Inverse Distance Weighted (IDW) used to interpolate rainfall and on statistical tests (Normality, Buishand, Pettitt and Hubert) applied on hydrometeorological and hydrometric data to analyze the hydrological functioning of BW. Hydropower generation at Kossou dam was analyzed with Pearson Chi square independence method according to Representative Concentration Pathways (RCP) 4.5 and 8.5 scenarios of CMIP5 (coupled model intercomparison project phase 5) and CORDEX-AFRICA (coordinated regional climate downscaling experiment). The results showed the variability of rainfall as well monthly, seasonal as annual from 1980 to 2013; the hydroclimatic variability in the basin characterized by the presence of breaks in stationarity in 1998 and 2008, and the variability of flow. The Buishand and Pettitt tests described these two ruptures. The segmentation of Hubert specified three sub-periods. The results also showed that there is an alternation of wet and dry periods followed by a slight resumption. The climate projection scenarios RCP 4.5 and 8.5 have shown that the change in the variability of rainfall and flow in the BW will have a negative impact on hydropower generation at Kossou from 2030 to 2050.