hydropolitics of the tigris - euphrates river basin with - ceris.be

effective tool for reducing the heavy impacts and destruction of flooding. These silt-rich river systems
slowly deposited their bedload as they moved across the plain, eventually building up layer by layer a river
bed (or levee) that rests at times above the surrounding plain. It is no surprise that such a structure often
became unstable during floods, at which time the rivers jumped their banks and changed their course. 5
The Euphrates
The majority of the headwaters for the Euphrates (about two-thirds) are located in the Turkish region of
Anatolia. The River begins with 2 tributaries, the Murat-Su and the Kara-Sue (or Frat-Sue) which meet
north of the city of Elazia. Here the river is almost entirely snow-fed from mountain streams. Flowing
southward, the Euphrates comes within 160km of the Mediterranean before it turns left into Syria to
continue in a south-westerly direction, almost straight towards the Persian Gulf. While traversing the barren
Northeast corner of Syria known as the ‘duck’s-bill’ (due to the triangular shape of this small piece of
territory) the Euphrates is joined by 2 tributaries; the Balikh and the Khabur rivers. There is not a large
volume contribution from these 2 rivers. As the Euphrates enters into Syria it carries an estimated 30 billion
cubic metres per year (BCM/Y), rising to 32 BCM/Y as it leaves Syria to enter Iraq. For the remaining
1000km of its journey in Iraq, no more water flows into the Euphrates.
The Tigris
The headwaters of the Tigris River begin in the small mountain lake of Jazar Golu in Turkey, 30 km from
the upper catchment of the Euphrates. The flow of the Tigris is augmented by the Batman-Su as it leaves
Turkish territory. Unlike the Euphrates, the Tigris flows directly towards Iraq and the Mesopotamian Plain
with only a brief parallel alongside the Syrian border. Only 20% of the length of the Tigris lies in Turkey.
The remainder lies in Iraq where it is fed by the Iranian-based tributaries of the Khabur, the Greater Zab
(partly beginning in Turkey), the lesser Zab, the Uzaym and the Diyala rivers which flow down from the
Kurdistan and the Zagros Mountains. 6
The mean annual flow of the Tigris before it enters into Iraq from Turkey is 20 to 23 BCM/Y, but during its
passage in Iraq it receives from all of the above tributaries an additional 25 to 29 BCM/Y. Calculation of
flows for both the Tigris and Euphrates Rivers is difficult due to annual as well as seasonal variations. A
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