Thirthar reservoir Iraq's water wealth

2024-05-24

Assistant Instructor Sulaf Taha Dawood Al-Fahdawi

Upper Euphrates Basin Developing Centre / University of Anbar

Lake Thirthar is the largest lake in Iraq and the second largest artificial body of water in the world, with an area of (2710) km2, a length of (120) km, and a width of (40) km, located between the right bank of the Tigris River and the left bank of the Euphrates River northwest of Baghdad about (120) km at the northeastern side of Anbar Governorate, and the southwestern side of Salah Al-Din Governorate, as well as it is the deepest natural depression in Iraq, as it reaches the deepest point (3) m below sea level at the southeastern tip thereof, The highest storage level reaches (65) m above sea level, the storage volume at this level is (85.39) billion m3, of which (35.81) billion m3 are dead storage at the level of (40) m above sea level, and (49.58) billion m3 live storage at the level of (65) m above sea level, and the storage volume is (70%) of the total volume of storage in Iraq, which is equal to the revenues of the Tigris and Euphrates from water for two years, the Thirthar project was used for the first time in diverting water The flooding of the Tigris River to the Thirthar depression in April and May of the year (1956), as the main objective of using this lake was to control the flooding of the Tigris River to protect Baghdad and the rest of the cities of the Tigris Plain from drowning, as well as to store water and control irrigation water during the summer.

Thirthar irrigation system:

1.      Thirthar-Euphrates channel: It extends from south of Thirthar lake to the Euphrates river at Sin Thibban pathway to the north of Falluja city. The works at this project were finished in 10-10-1976. The length of Thirthar-Euphrates channel was 37.5 km with water discharge design of 1100 m3 per second distributed to the channels below.

2.     Tigris arm (Thra’a Dijla) channel: It branches off from the main channel (Tharthar-Euphrates channel) by regulator at (27) km to head east until it meets the Tigris River in the Taji area north of Baghdad with a length of (65) km, and a width of (60 m), with a design discharge (600 m3 per second), as work was started on (1/1/1977), until the drilling was completed and the establishment of a regulator in (1981). In (1988) the water was diverted to it for the purpose of benefiting from it in diverting the water of Tharthar Lake was converted towards the Tigris at the time of the extremely hot weather on the one hand, and reviving the agricultural lands that pass through it within the islet of Garma as well as feeding the Ali Suleiman project with water by Concrete siphon.

3.     Diversion Project (Irrigative Thirthar Project): This channel extends from the front of the Samarra dam and runs along the Samarra-Anbar dam road, then it deviates towards the south and when it enters the province of Anbar it deviates again towards the west to flow into the main Thirthar channel from the source of the Thirthar channel, that is, before the Tigris arm branches from the canal by (400) m, the length of this project is (96.5) km and a discharge of (250) m3 per second. The purpose of this project is to reduce the salinity of the water released from Lake Thirthar towards the Tigris and Euphrates rivers, and this project is known locally as (Desalination Project), this project was started in (1981) and was completed at the end of (1987).

Thirthar irrigation system

The Dutch consulting company (Nedeco) submitted its comprehensive report (1959), which is summarized as follows:

1.     It is possible to store (72.8) billion m3 of water in the lake up to a height of (60) m above sea level, and it is possible to divert the floodwaters of the Euphrates River to the lake by building a dam on the river at Heet and opening a stream that takes water from the front of the dam and ends with the lake in the southwest.

2.     The Thirthar Lake is solid pan and watertight and there is no fear of water seeping into the surrounding areas from the south.

3.     When the lake is used as a reservoir for irrigation water, the stored water will become in the long run of good quality, in terms of salinity, through the process of filling and dispersing that will be periodically.

4.      The Tigris and Euphrates rivers can be equipped with lake water through the exit pathway channels.

5.     The Tigris River can be fed with the water of the Euphrates River by opening a feeding channel from the Euphrates River at Saqlawiya and flowing into the Tigris River north of Baghdad.

6.     The lake is very suitable for fish farming.

7.     Electrical power can be generated at the Heet dam after completion.

#university_of_anbar
#Upper_Euphrates_Basin_Developing_Center