Tigris–Euphrates river system border. Since the 1960s and in the 1970s, when Turkey began the GAP project in earnest, water disputes have regularly occurred in addition to the associated dam's effects on the environment. In addition, Syrian and Iranian dam construction has also contributed to political tension within the basin, particularly during drought. The general climate of the region is subtropical, hot and arid. At the northern end of the Persian Gulf is the vast floodplain of the Euphrates, Tigris, and Karun Rivers, featuring huge permanent lakes, marshes, and forest. The aquatic vegetation includes reeds, rushes, and papyrus, which support numerous species. Areas
Karasu (Euphrates) pitch by locals. Karasu (Euphrates) The Karasu (Turkish for 'black water') or Western Euphrates is a long river in eastern Turkey, one of the two sources of the Euphrates. It has a length of about 450 km. To the ancient Greeks the river was known as the ("Telebóas"). The river rises on the Dumlu Dağ in Erzurum Province, and drains the plains around the city of Erzurum. It is joined by the Serçeme River, then flows west through Erzincan Province, turning south, then west and receiving the tributary Tuzla Su. Between Erzincan and Kemah it is joined by the Gönye