The hydrology of the Ganga River is mainly characterized by high monsoon rainfall and seasonal variability in discharge flow. The study is focuses on both the up and down-streams of Farakka barrage. It has been executed with the help of Modified Normalized Difference Water Index using Landsat satellite images (2014), satellite based discharge data and Gumbel’s flood frequency analysis. The study aims to analyse the impacts of seasonality, floods and the construction of Farakka barrage on hydrology of the Ganga River.