Asyut weir
| Asyut weir Assiut Barrage |
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| Coordinates | 27 ° 12 '8 " N , 31 ° 11' 21" E | ||||||||
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| Lock type: | Gravity dam | ||||||||
| Construction time: | 1898-1902 | ||||||||
| Crown length: | 790 m + 30 m lock structure | ||||||||
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The Asyut weir ( Arabic قناطر أسيوط Qanāṭir Asyūṭ , English Assiut Barrage ) is a dam over the Nile near Asyut in Egypt .
The first Asyut weir was built between 1898 and 1902 in order to discharge the Nile water from the Aswan Dam, which was built at the same time and located about 540 km upstream, into the Ibrahimiyya Canal during the low water period . This canal irrigates the fields to the left of the Nile over a length of 350 km and also directs water into the Fayyum basin via the Bahr Yusuf , the Joseph Canal . The canal was also given an inlet structure for precise regulation.
The first Asyut weir was reinforced in 1938. The function of the Aswan weir has since been taken over by the Aswan High Dam ( Aswan High Dam ). The new Asyut weir was built from 2012 to 2018 and was inaugurated in August 2018.
description
The old Asyut weir stands 500 m below the inlet of the Ibrahimiyya Canal. The gravity dam has a straight plan, its dam crest is 790 m long today, after parts of the original wall and the adjoining earth dam were covered by the later built embankment walls. On the western bank there is a 30 m wide lock structure with a 16 m wide lock chamber and a bascule bridge for the two-lane road on the top of the dam. The wall is, calculated from the foundation plate, 12.5 m high. It consists of granite - stone blocks with a core of rubble masonry . It has 111 bottom outlet gates , each 5 m wide and framed by 2 m thick pillars, and operated by a large portal crane on the top of the dam. However, every ninth pillar is 4 m thick, resulting in a long row with groups of nine gates each.
The intake structure for ibrahimiya canal ( English Assiut Head regulator ) is in Asyut approximately 250 m after the beginning of the channel. It has nine inlet gates, each 5 m wide, and a smaller lock. A two-lane road with wide sidewalks leads over the structure.
history
The Ibrahimiyya Canal was built between 1867 and 1873 by the Khedive (viceroy) Ismail Pasha , primarily to be able to irrigate his sugar cane fields all year round. It branched off from the Nile in Asyut without any special initiation measures and was therefore dependent on the water flow of the Nile, which fluctuated greatly between high tide and summer low tide.
During his rule over Egypt, which lasted from 1805 to 1848, Muhammad Ali Pascha ordered the construction of the Delta Barrages , which were not completed until after his death, but with which the conversion of irrigation methods on the Nile from seasonal irrigation in flood basins to year-round irrigation through canals was initiated.
The British created the project to dam the Nile in Aswan and to stockpile and controlled in Asyut to distribute between the river and the canal, the basis to introduce the full-year canal irrigation on a large scale. The dam, like the dam in Aswan, was designed by William Willcocks and William Edmund Garstin and built by Sir John Aird & Co. on the basis of funding provided by Sir Ernest Cassel . Benjamin Baker was the consulting engineer here as well.
The first Nile flood immediately after the completion of the project in 1902 was exceptionally low and late. There was a risk that a large part of the maize cultivation could not take place due to a lack of irrigation. Due to a risky decision, all gates in the new weir were closed on August 15th and the Nile was dammed by 1.5 m. This meant that there was just enough water available in the Ibrahimiyya Canal to save the harvest. Its value was estimated at £ 600,000 compared to the construction cost of the weir of £ 870,000.
The weir was completely renovated between 1934 and 1938.
New barrage
Between 2000 and 2005, various considerations and feasibility studies financed by the Kreditanstalt für Wiederaufbau (KfW) came to the conclusion that a new building with a hydropower plant about 200 m below the existing weir was the cheapest solution compared to renewed renovation. In the summer of 2012 the foundation stone was laid for the new barrage and hydropower plant, the completion of which was planned for the end of 2017. The new weir, which around 7,000 people were employed to build, was inaugurated in August 2018 by the Egyptian President Abd al-Fattah as-Sisi . KfW contributed around 300 million euros to the financing of this water project. The new weir includes a hydroelectric power station with a total of 32 MW output (four turbines with 8 MW each) and a double lock as a ship lift for ship traffic.
See also
Individual evidence
- ↑ a b c d Christoph Albrecht-Heider, Sebastian Jacobi: The new Asyut weir over the Nile ensures water supply for five million Egyptians. Infrastructure: mammoth construction for smallholders. In: KfW> Stories> Economy> Infrastructure. KfW, October 22, 2018, accessed on September 6, 2019 .
- ^ William Willcocks, James Ireland Craig: Egyptian Irrigation . Volume II. 3rd edition. Spon, London / New York 1913. pp. 655 f
- ^ TJF Hill: Assiut Barrage, to rehabilitate or to rebuild
- ↑ Ayman F. Batisha: Assiut Barrage in Egypt: Past, Present and Future. Summary in Irrigation & Drainage Systems Engineering , Volume 1, 2012
- ↑ Laying of the foundation stone for the new Assiut barrage and hydropower plant in Egypt. ( Memento of the original from April 19, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. Information from July 9, 2012 on the Lahmeyer International website
- ^ Assiut Barrage . ( Memento of the original from April 19, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. Information dated April 10, 2013 on the VINCI-Construction website
