A coastal management case study in Karasu at black sea region

Coastal erosion may be caused by natural causes as well as human factors. In Karasu, human activities such as sand and sand mussels mining, dam construction on river Sakarya which is a sediment source, building of coastal engineering structures and urban interference into beach areas have been recognizes as important contributors to coastal erosion. The length of eroded beach in Karasu is reported as 30 km where Acarlar deep spot located at the total of 80 km coastline. Acarlar is the one of the biggest deep spot in the world. Acarlar deep spot is protected by sand dunes along the beach. The width of the beach is 1km at some varied locations. However Acarlar deep spot is under threat of coastal erosion. The paper describes, the morphological changes in the mouth of Sakarya River, north-west Turkey, caused by the retention of sediments due to various dams constructed, since 1967, in the Sakarya River basin with emphasis on a collection of satellite images obtained since the 2000 decade, and considering also historical maps and aerial photos. Semi-quantitative results of the regression of the coastline and the temporal variation of its alignment, considering the interface of the vegetation and the sand as reference for the erosion processes, are presented. A couple model was run to determine the morphology and coastal variation in Karasu Beach.