Aswan Dam insignificant compared to what is needed to reach the yields achieved today in Egypt's irrigation. Also, the annual spread of sediment due to the Nile floods occurred along the banks of the Nile. Areas far from the river which never received the Nile floods before are now being irrigated. A more serious issue of trapping of sediment by the dam is that it has increased coastline erosion surrounding the Nile Delta. The coastline erodes an estimated per year. Before the construction of the High Dam, groundwater levels in the Nile Valley fluctuated 8–9 m per year with the water level
Grand Ethiopian Renaissance Dam govern the impacts during the reservoir filling phase include the initial reservoir elevation of the Aswan High Dam, the rainfall that occurs during the filling period and the negotiated arrangement between the three countries. These studies also show that only through close and continuous coordination, the risks of negative impacts can be minimized or eliminated. The reservoir volume (74 billion cubic meters) is about 1.5 times the average annual flow (49 billion cubic meters) of the Blue Nile at the Sudanese-Egyptian border. This loss to downstream countries could be spread over several years if the countries reach an agreement. Depending