Ghionis, G., Poulos, S.E. and Karditsa, A., 2013. Deltaic coastline retreat due to dam presence: The case of river Alfios mouth area, Kyparissiakos Gulf, Ionian Sea.

The deltaic coast of the Alfios river, and especially its mouth area, is undergoing intense erosion over the last decades. This erosion has been caused primarily by the dramatic reduction of the fluvial sediment fluxes, following the construction of two dams (in 1954 and 1967), with the second dam being located at a distance of only 6 km from the river mouth. A further decrease in sediments reaching the sea is induced by the extended (even not continuous) abstraction of sand and gravel from the river's lower route. The resulting sediment deprivation in association with the highly energetic nearshore hydrodynamic regime has caused a retreat of approximately 450 m (from 1945 to 2003) of the mouth area of the R. Alfios. The northern part of the mouth has been affected more heavily by the erosional processes (shoreline retreat between 200 and 445 m) than the southern part (100–240 m retreat), the sediment losses of which are partially replenished by the northward longshore sediment transport of Kyparissiakos Gulf. Shoreline retreat at distances >1 km on either side of the river's mouth is approximately equal, becoming minimal at distances >2 km. The erosional trend of the Alfios River deltaic coast, that has caused significant property losses and damage to coastal infrastructure, is expected to continue and may become more intense as a response to the anticipated future sea level rise.