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Turkey's Transboundary Waters

Turkey's transboundary water
source: institue for the study of war, bloomberg research

Turkey has five transboundary river basins. From north to south, they are Çoruh River Basin, Aras River Basin, Euphrates-Tigris River Basin, Asi (Orontes) River Basin; and in the west, the Meriç (Maritza) River Basin. These basins occupy an important position in Turkey’s international relations because of their transboundary characteristics. Just over 35% of Turkey’s water potential is composed of transboundary waters.[1]

Euphrates and Tigris rivers

The Euphrates-Tigris River Basin is among the most important river basins in Turkey and the Middle East. The combined average annual discharge of the Euphrates and Tigris rivers is 84BCM, which is comparable to the average annual flow of the River Nile. The Euphrates provides 90% of the water, with an average annual flow of 32BCM, from Turkey; and 10% from Syria. The average annual flow of the Tigris is 52BCM. The average annual flow of the Tigris at the Cizre gauging station is 16.2BCM.

The Euphrates-Tigris River Basin is a vital source of energy, food and drinking water for Turkey, Syria and Iraq, which are the main riparians to the basin. Turkey considers the Euphrates-Tigris River Basin as a single basin whereas Syria and Iraq treat the two rivers separately. The riparians have been working on developing the basin waters since the 1950s.[2] In this period, the DSİ built respectively the Keban, Karakaya and Atatürk dams on the Euphrates River. Several dam projects were then constructed in Syria on the Euphrates and Asi (Orontes) rivers, two of the country’s most important water resources. Tabqa, Syria’s largest dam, was built in 1968.[3]

During the filling process of the Keban and Tabqa dams and the construction of Atatürk Dam, a dispute broke out between Turkey, Syria and Iraq. Iraq reacted strongly to Syria reducing the water flow to its country. While basin states maintained their water projects, Turkey and Iraq established a Joint Technical Committee (JTC) in 1981 to use waters effectively, wisely and fairly. Syria participated in the JTC in 1983. Negotiations were suspended after the 16th meeting of JTC in 1992. Nevertheless, tripartite meetings were held again in 2007 at a technical and political level. Turkey agreed to release 500m3 of water per second until final agreement among the three riparian countries as stipulated in the protocol signed between Turkey and Syria in 1987. Turkey has fulfilled this commitment for 27 years.[4]

The Adana Accord signed between Turkey and Syria in 1998 provided a basis for cooperation in many fields including tourism and trade. In this context, a cooperation protocol concerning water resources was signed in 2001 between the GAP Regional Development Administration and the General Organization of Land Development (GOLD).[5]

Turkey signed a memorandum of understanding (MOU) with Syria and Iraq in 2009. The agreement included monitoring of water resources, joint projects and protocols, and fighting climate change. One of the protocols between Turkey and Syria envisages the construction of the joint Friendship Dam on the Asi River. Construction began on 6 February 2011, but the Syrian uprising that began the following month has set the project back.[6]

Asi (Orontes) River

Turkey is a downstream country on the Asi River, unlike the Euphrates and Tigris rivers. The Asi originates in the Bekaa Valley in Lebanon, and enters Syria after about 40km. There is no definitive data either on the length of the river or its flow. Different sources quote the length of the river as anything from 248km to 571km and annual flow varies from 1.2BCM, according to Turkish data, to 2,751BCM according to Syrian information.[7]

Çoruh River

The overall length of this river is 431km. After it leaves Turkey, it flows through Georgia for 21km before emptying into the Black Sea at Batum. The river’s water potential is 6.4BCM. Turkey has planned ten dams and hydroelectric stations on the river, which will provide 10.5 billion kWh annually. Once completed, these projects are expected to provide 6% of Turkey’s overall hydroelectric potential.[8]

Aras and Kura rivers

The Aras and Kura rivers originate in Turkey.The Aras provides 45% of the total water flow of the basin while the remaining 55% is provided by the Kura. The Kura flows for 210km in Turkey before crossing into Georgia and flowing another 390km there. The Kura River Basin, with a length of 1,364km, covers an area of 88,000km2. The Aras River flows for approximately 300km in Turkey and then forms the border between Turkey, Armenia, Azerbaijan and Iran. On the border between Azerbaijan and Iran, the Aras joins the Kura and they reach the Caspian Sea together in Azerbaijan. The estimated average flow of the Aras River is 2,190BCM in Turkey. Agriculture and animal husbandry are the main economic activities in the Turkish part of the basin, where water quality deterioration is a major problem.[9]

kura river
Kura River, (Photo: Doron.)

Meriç (Maritza) River

The Meriç River originates in the Rila Mountains in Bulgaria. According to the Meriç Bridge gauging station in Turkey, the average flow of the river, whose basin is 53,000km2, is 147m3/s. The river flows for 320km through Bulgaria then runs for 240km along the border between Turkey and Greece before emptying into the Aegean Sea. Besides its main reach, the Meriç River merges with four other reaches. These are Arda, Tunca, Kızıldeli Su (Erythropotamos) and Ergene. The main problems facing the Meriç River Basin are flooding and pollution, although during the summer months it can also experience droughts. Turkey, Greece and Bulgaria have signed separate agreements with each other to improve flood protection. However, there is no agreement related to the Meriç River waters among these countries.[10]


[1] DSİ, 2014, DSİ and Water, Ankara, p.24.
[2] Özden Bilen, 2000, Turkey &Water Issues in the Middle East, DSİ, p.34; Aysegul Kibaroglu, Annika Kramer, Waltina Scheumann (ed.), 2011, Turkey’s Water Policy National Frameworks and International Cooperation, Springer, London, p.279-280.
[3] Ayşegül Kibaroğlu, 2002, Building a Regime for the Waters of the Euphrates and Tigris River Basin, Kluwer, p.170.
[4] Aysegul Kibaroglu, Annika Kramer, Waltina Scheumann (ed.), 2011, Turkey’s Water Policy National Frameworks and International Cooperation, Springer, London, p.281.
[5] Aysegul Kibaroglu, Annika Kramer, Waltina Scheumann (ed.), 2011, Turkey’s Water Policy National Frameworks and International Cooperation, Springer, London, p.281.
[6]Turkey, Syria, Iraq sign MoU for use of water resource”, 04/09/2009 , Also: Turkey –Syria Relations.
[7] Samir Salha, Türkiye, Suriye ve Lübnan ilişkilerinde Asi Nehri Sorunu, Dış Politika Enstitüsü, 1995, p.15.
[8] DSİ, 2014, DSİ and Water, Ankara, p. 45
[9] United Nations Economic Commission For Europe, 2011, Second Assessment of Transboundary Rivers, Lakes and Groundwaters, p.151.
[10] Tuğba Evrim Maden, 2010, European Union Water Framework Directive: Case Study Meriç (Maritza) River, unpublished PhD thesis, Ankara University, Ankara, Turkey.