Ahmadreza Palizvan - K.N. Toosi University of Technology, Tehran, Iran
Mansoure Mashhadi - K.N. Toosi University of Technology, Tehran, Iran
Mohsen Soltanpour - K.N. Toosi University of Technology, Tehran, Iran,
Babak Banijamali - Daryabandar Consulting Engineers, Tehran, Iran

Tang inlet is located in the south Iranian border at Gulf of Oman, connecting a seasonal river to the open sea (Fig. 1). The local people use the tide-dominant Tang inlet as a natural fishery harbor, where the offshore reef protects the entrance against large waves [1]. A pier has also been constructed in the lagoon. Existing aerial and satellite images from 1967 up to the present and the interviews with local people reveals that the tombolo behind the reef has experienced interesting natural periodic migrations in time spans of about 8-15 years (Fig. 2). The periodic shifts of port entrance has resulted to the suffering of the fishermen and in particular, the shallow water depth and the rocky bed of west entrance is highly dangerous and undesirable for navigation.