COASTAL EROSION OF THE BAFRA PLAIN NEAR THE KIZILIRMAK RIVER MOUTH AND PROTECTON STRUCTURES

摘要

The coastline of the Bafra Plain near by the Black Sea and Kizilirmak junction have been eroding since the sediment budget of the Kizihrmak River was altered by the regulation structures. It was determined that every year approximately 30 m wide coastal band of the Bafra plain in the vicinity of the Kizihrmak River mouth has been lost due to the effects of Black Sea waves. A study was made to prevent this erosion by means of Y and I type groin combination designed by physical model studies. Part of these structures consists of L and I type groins at the mouth and Y and I type groin combination at approximately 1200 m long coastline adjacent to right side of the Kizihrmak River mouth were constructed. Observations performed in the field after the completion of groins at the Kizihrmak mouth and along 1000 m coastline adjacent to the river mouth showed that the erosion was completely stoped. It was also determined that some parts of the coastline at this reach advanced to the sea approximately 50 m. However, the erosion accelerated approximately 1400 m long coastline adjacent to the right side of the coastline where groins were constructed. Additional experimental model studies were performed and five I type groin combination were designed to protect this portion of the coastline of the Bafra Plain. Experimental studies showed that this portion of the coastline could be protected and stabilized after the completion of those groins.