Nile Delta Shoreline Changes: Aerial Photographic Study of a 28-Year Period

Abstract

Airphotographic analysis is used to detect erosional and accretionary changes, and to define coastal features along some stretches of the Nile Delta coast of Egypt. Two series of aerial photographs, taken in 1955 and 1983, were applied to three unstable coastal zones: the Rosetta and Damietta promontories, and the Burullus-Baltim sector. Comparison of the two successive photo surveys serve to monitor the impact of the Nile River control and the coastal dynamic regime. The study reveals that the outer margin of both Rosetta and Damietta promontories seem to be the most eroded areas. These promontories are retreating due to the cut off the sediment supply after damming the river. The estimated highest rate of erosion during the 28-year period is: 114, 9 and 31 m/yr respectively, at Rosetta, Baltim and Damietta sectors. Remarkable accretionary patterns are also coupled with shoreline erosion, as has been noticed on the eastern side of the two promontories, and to the west of Burullus inlet. Moreover, photographic analysis helps to detect some salient coastal features such as the ancient coastal sand ridges east of the Rosetta and Damietta promontories, and a distinct spit southeast of the Damietta promontory. The prevailing eastward longshore drift of sediments from the adjacent beaches associated with the strong decrease of sediment supply from the Nile River upon completion of the Aswan High Dam in 1964 are responsible for the detected erosional and accretionary phenomena along the three study areas.