Research regarding anthropogenic effects on flood inundation and morphological/landscape change in the River Niger is presented in this thesis. Various anthropogenic effects are considered within the case study area. Effects of dam construction were numerically modelled using Dynamic Harmonic Regression (DHR) Model, Geographical Information System (GIS) and Cellular Automaton Evolutionary Slope And River model (CAESAR). CAESAR model was used to simulate different flood scenarios resulting from environmental change (climate and anthropogenic land cover change) on the River Niger. Most pm1s of the Niger River Basin lack spatially distributed hydrological data to facilitate efficient monitoring of anthropogenic effects on the river. The use of parsimonious models such as Dynamic Harmonic Regression models which require few spatially-distributed data are therefore suitable for simulating water stages behaviour/response to anthropogenic effects, in this case, the Kainji and Jebba Dam constructions. DHR routines were used to simulate the dynamics of pre- and post-dam constmction water stages within the River Niger Basin in Nigeria. The DHR model explicitly calculates the uncertainty in the estimated cycles and trends and thereby ensures that the data are not over-interpreted. Seasonal cycles and trend in water stage data across the Niger River Basin within Nigeria before and after Kainji and Jebba dams construction were captured using this model. It has robustly quantified a range of differences in the water stage regimes after the dam construction especially at the immediate downstream gauge station. These differences, however, dissipate further down the downstream catchment towards the Niger Delta.