Great Zab
The Great Zab rises in Turkey in the mountainous region east of Lake Van at an elevation of approximately amsl and joins the Tigris on its left bank in Iraq. In Turkey, the Great Zab traverses the provinces of Van and Hakkâri, whereas in Iraq it flows through Duhok Governorate and Erbil Governorate, both part of the Kurdistan Region. Together with the Tigris, the Great Zab forms the boundary between Erbil Governorate and Ninawa Governorate. In its upper reaches, the Great Zab flows through steep, rocky gorges. The stretch between Amadiya and the Bekhme Gorge, where the Bekhme Dam remains unfinished, has been called the Sapna valley and will have a large portion of it inundated with water if the project is completed. Numerous mountain streams and wadis join the Great Zab on its right and left banks. The Great Zab receives most of its waters from the left-bank tributaries; the Rubar-i-Shin, Rukuchuk, Rubar-i-Ruwandiz, Rubat Mawaran and Bastura Chai.