Modification of Niger Delta physical ecology: The role of dams and reservoirs

The Niger Delta is a 40-km2 sedimentary basin with a complex river network and a fragile ecology in which fresh and saline water ecosystems maintain a dynamic equilibrium. Large-scale upstream impoundment in dams and reservoirs have over the years drastically reduced flow and sediment delivery to the coast resulting in adjustments to ecological boundaries, coastline geometry, lowered flood water levels and upstream migration of tidal influences. However, as the reservoirs get silted up, they no longer function as effective flow buffers, occasioning increased floods towards the pre-dam levels.