Khashm el-Girba Dam

The Khashm el- Girba Dam (also Chaschm al - Qirba Dam ) dams the Atbara in the state of al - Qadarif in Sudan.

Reservoir

The formed from Khashm el- Girba dam about 5 km wide reservoir extends over a length of about 50 km in the north-south direction from the place Khashm el Girba to a few kilometers below the town Showak close to the borders of Sudan - Ethiopia - Eritrea in the southeastern Butana steppe. Its water level is at an altitude of 470 m above sea level

Dam

The Kashm el- Girba dam consists of a 47 m high concrete gravity dam with a crest length of 450 m, 2 x 5 MW Kaplan turbines, 3 x 8 MW pumps and 15 goals. The dam is surrounded on both sides by 1800 m and 1500 m long dam.

The Kashm el- Girba dam was 1960 - 1964 built to give the persons displaced by the Aswan Dam and the rising waters of Lake Nasser about 50,000 residents from the area of ​​Wadi Halfa in the New Halfa project a new livelihood. It is therefore mainly for irrigation project ( 500,000 feddans about 2100 km ²). In the dam, therefore, a large outlet structure is included, with the most of the water is drained through a large channel to the irrigation systems. If the water level falls below the level of the channel, the channel can be filled with the pump then from the deeper sea.

Hydrology

The dam impounds Atbara, which is called because of its high sediment load and "Black Nile ." This alluvial material leaves the lake silt up quickly. 1974, ten years after the first Vollstauung, the volume had to of formerly 1.3 km ³ 0.66 km ³ halved. irrigation of New Halfa project therefore had to be reduced.

In order to reduce further sedimentation, the reservoir was completely drained in 1970 once a year on the bottom outlet of the dam. This is done on the rising tide to flush out as many sediments. The thereby occurring large fish kills seem to have on the fish population of the Atbara little influence.

Nevertheless, the inadequate water supply of New Halfa project and the Sedimentationsproblem has meant that started above Showak with the construction of two new dams ( Rumela Dam and Burdana Dam ).

Since the dam is used primarily for irrigation, hardly any water is discharged to the river in the underwater during the low water phase. As a result, the agricultural use has changed dramatically along the lower reaches of the Atbara due to the lack of water.