Tigris–Euphrates river system Tigris–Euphrates river system The Tigris and Euphrates, with their tributaries, form a major river system in Western Asia. From sources originating in eastern Turkey, they flow by/through Syria through Iraq into the Persian Gulf. The system is part of the Palearctic Tigris–Euphrates ecoregion, which includes Iraq and parts of Turkey, Syria, Iran, Saudi Arabia, Kuwait, and Jordan. From their sources and upper courses in the mountains of eastern Anatolia, the rivers descend through valleys and gorges to the uplands of Syria and northern Iraq and then to the alluvial plain of central Iraq. The rivers flow in a south-easterly direction
Euphrates of , the Atatürk Dam reservoir is large enough to hold the entire annual discharge of the Euphrates. Completion of GAP was scheduled for 2010 but has been delayed because the World Bank has withheld funding due to the lack of an official agreement on water sharing between Turkey and the downstream states on the Euphrates and the Tigris. Apart from barrages and dams, Iraq has also created an intricate network of canals connecting the Euphrates with Lake Habbaniyah, Lake Tharthar, and Abu Dibbis reservoir; all of which can be used to store excess floodwater. Via the Shatt al-Hayy, the