Great Man Made River Project

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False color photo of the artificial water reservoirs at Grand Omar Mukhtar. Round reservoirs with water (dark blue color) can be seen at the bottom and top right, the vegetation appears red. Buildings and infrastructure are shown in gray, sand and steppe soil in beige.
Map of the GMMRP on a Libyan 20 dinar note
The Great Man Made River project is documented in detail on the front and back of the Buddy Bear - in front of the new Libyan embassy in Berlin-Dahlem .

The Great Man-Made River (. GMMRP or GMMR, dt Project Big man-made river ) in Libya was the world's largest drinking water - pipeline project for a better water supply of population and agriculture.

Fossil groundwater from the deep-lying reservoir rocks of the Nubian sandstone aquifer , the Kufra basin, Sirt basin, Murzuk basin, Hamadah basin and Jufrah basin of the Sahara desert is fed and supplied in the four meter high pipes in the direction of the Libyan Mediterranean coast For several years now, the two cities of Tripoli (since 1996) and Benghazi as well as the entire coastal region with water. The pipeline runs parallel to large parts of the Libyan coast and transports more than 6 million m³ of drinking water every day. The water quality and the associated quality of life there has improved considerably since then.

The tapped reservoirs have no inflows, so this is the consumption of a non-renewable resource. How long the water reserves will last is a matter of dispute. According to calculations by the then incumbent Libyan government, Gaddafi, the amount of fossil water would last for at least 4,000 to 5,000 years. Optimistic estimates today speak of a useful life of up to 250 years, international experts, on the other hand, of 30 to 50 years at maximum output.

history

Irrigation systems have been installed in the Sahara desert since 1984, financed by the government of Muammar Gaddafi . These pump water from underground reservoirs that date back to the last ice age . These water reserves were discovered during oil drilling in the 1950s. The aim of this project is to supply the population and agriculture in the coastal areas and in the vicinity of the pipelines with water. In addition, parts of the desert are made fertile so that different plantations (e.g. date palms ) are created in the desert, which are irrigated with the help of the GMMR project. Another goal is to expand agriculture to such an extent that it is also possible to export crops.

On July 22, 2011, one of the two existing pipe factories near Brega was the target of an air strike by NATO during the civil war in Libya . The reason for the attack was that the factory premises were used as a military warehouse and rockets were fired from there.

On May 19, 2019, militias occupied the GMMRP control station for the water supply in Tripoli and forced the workforce to shut off the supply. The supply could be restored two days later.

Effects

Before the infrastructure project, the tap water in the coastal region was contaminated with a considerable, sometimes disease-causing salinity. In addition to improving the quality of drinking water, the intention is to use water to develop Libya into an agricultural export country. The feared - and partly occurred - effects are the lowering of the groundwater level . Although the ice age water is more than 300 meters below the surface of the earth, it is not clear whether - as has happened in some cases - the groundwater level, which is 10 to 60 meters deep, is influenced over a large area.

Pipeline tubes of the GMMR (2004)

Although it was co-initiated by foreign engineers in the initial phase (South Korean companies built factories, Germans developed the system: know-how exchange), today the entire, world's largest project of its kind is in purely Libyan hands. Libya sees this project as an infrastructure and educational factor.

The reinforced concrete pipe sections are produced in two factories in northeast Libya, in Brega and Sarir . According to the prestressed concrete principle , they contain steel wire wound under tension. This is necessary to withstand a water pressure of up to 60 bar. The outer diameter of the widest pipes is 4 m.

In the initial phase, the pipeline broke. In the production of the pipes, the pipes were not coated on the outside. This allowed moisture from the ground to penetrate the concrete. As a result, the tension wire under the outer layer of concrete corroded and the pipes broke.

Pipes destroyed by corrosion

The fossil water in the different well fields is of very different quality. The water in the Tazerbo well field is particularly heavily polluted with iron , manganese and CO 2 . In order to avoid damage to the pipeline, water treatment systems were installed at the 108 wells. Every well and therefore every water treatment plant in this field has an output of 420 m³ / h. Because of the huge dimension of the well field (1,000 km²) and the immense conveying capacity of 1.08 million m³ / day, a central water treatment plant could not be used. Other well fields, such as the one in Sarir, on the other hand, manage without a water treatment system and feed the extracted water directly into the pipeline.

Central control

The nationwide pipeline network is monitored at a headquarters under the responsibility of the Great Manmade River Authority (GMMRA). The aim is - technically demanding - not only to evaluate all data supplied by sensors , but also to be able to centrally control every valve, every machine and all equipment. Alternatively - e.g. B. in the event of a power failure - but local interventions can also be carried out.

financing

During the construction period, Libya levied a GMMR tax, which at least international air travelers had to pay as additional passenger taxes. In addition, the oil export is likely to have been a key source of finance.

literature

  • Konrad Schliephake: The Great Artificial River in Libya . In: Günter Meyer (Hrsg.): The Arab world in the mirror of cultural geography . Publications of the Center for Research on the Arab World (ZEFAW) Volume 1, Mainz 2004, pp. 210–213.
  • Peter Münder: The secret of the desert tunnel . In: Spiegel Special of November 1, 1998, No. 11, p. 112 ff.
  • Erich Johann Papp: The “Great Man Made River” project . (PDF; 317 kB) In: FORUM Gas Water Heat , 1/2007.

Movies

  • Libyan Sahara. Water from the desert. Documentary, Austria, 2001, 44 min., Book: Felix Koßdorff, director: Michael Schlamberger, production: ScienceVision, ORF , first broadcast: October 4, 2001, film information from 3sat with photos.
  • Libya's desert water - the artificial river through the Sahara. Documentary, Germany, 2005, 50 min., Script and director: Jens Dücker, production: arte , first broadcast: January 18, 2006 by arte, film information and online video .

Web links

Commons : Great Manmade River  - Collection of Images, Videos and Audio Files

Individual evidence

  1. ↑ Libyan Sahara. Water from the desert . In: 3sat , October 4, 2001.
  2. ↑ Martin Gehlen: Sahara water for Libya's coast . Zeit Online , December 27, 2010.
  3. ^ Libya says six killed in airstrike near Brega . In: Reuters . July 22, 2011 ( reuters.com [accessed December 26, 2018]).
  4. ^ NATO bombs the Great Man-Made River. In: Human rights investigations. July 27, 2011, accessed December 26, 2018 .
  5. ^ "Water supply restored for millions in Libya, averting crisis" The Guardian of May 21, 2019

Coordinates: 25 ° 27 '  N , 21 ° 36'  E