Euphrates

River rising in east Turkey and flowing through Syria and Iraq, joining the River Tigris above Basra to form the River Shatt-al-Arab at the head of the Gulf; length 3,600 km/2,240 mi. The ancient cities of Babylon, Eridu, and Ur were situated along its course and depended largely for their prosperity on irrigation from its waters.

Course The Euphrates rises in two branches: the Kara Su rises about 30 km/19 mi northeast of Erzurum, in the Kargapazari Mountains; and the Murad rises 70 km/43 mi northeast of Lake Van. Both these rivers flow in a southwest direction until they unite near Keban. The united stream then continues to flow southwest to Samsat, having forced a passage through the main range of the Taurus Mountains and formed a succession of rapids and cataracts. It then flows southeast across Syria and into Iraq at Abu Kemal to its junction with the Tigris at Al Qurnah, and the joint river, now called Shatt-al-Arab, empties itself by several distributaries into the Gulf. Formerly the Tigris and the Euphrates each preserved a separate course to the sea. The distance between the two rivers varies from 30 km/19 mi to 300 km/190 mi. The main tributaries of the Euphrates after it emerges from the mountains are, on the right bank, the Sajur Suyis and, on the left bank, the Belikh and the Khabur. The river is navigable for small craft as far as Hit, a distance of 1,900 km/1,180 mi, while larger vessels can progress as far as the confluence with the Tigris. The construction of dams in Turkey and Syria has greatly reduced the amount of Euphrates water available to Iraq. The consequences for Iraqi agriculture have been catastrophic, with a build-up of salt in the fields of southern Iraq drastically reducing yields.