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
Euphrates partitioned. Clause 109 of the treaty stipulated that the three riparian states of the Euphrates (at that time Turkey, France for its Syrian mandate and the United Kingdom for its mandate of Iraq) had to reach a mutual agreement on the use of its water and on the construction of any hydraulic installation. An agreement between Turkey and Iraq signed in 1946 required Turkey to report to Iraq on any hydraulic changes it made on the Tigris–Euphrates river system, and allowed Iraq to construct dams on Turkish territory to manage the flow of the Euphrates. The river featured on the