Great Man-Made River

The Great Man -Made River Project ( GMMR GMMRP or, dt Great man-made river project) in Libya is the world's largest drinking water pipeline project to improve water supply to the population and agriculture.

In the four -meter-high tubes fossil groundwater is managed and supplied from low-lying reservoir rocks of the Nubian Sandstone aquifer, the Kufra Basin, Sirt Basin, Mourzuk Basin, Hamadah Basin and Jufrah - basins of the Sahara desert in the direction of the Libyan Mediterranean coast for some years the two cities Tripoli ( since 1996) and Benghazi as well as the entire coastal region with water. The pipeline runs parallel to much of the coast of Libya and transported more than 6 million cubic meters of drinking water daily. The water and the related quality of life has since improved significantly there.

The tapped reservoirs have no inflows, it is here so the consumption of non-renewable resource. As long as the water reserves will be sufficient is debatable. According to calculations of the then reigning Libyan Gaddafi regime fossil water quantity was sufficient for at least 4,000 to 5,000 years. Optimistic estimates speak today of up to 250 years service life, international experts, however, from 30 to 50 years at maximum flow rate.

History

Since 1984, irrigation systems were installed in the Sahara desert. This pump water from underground reservoirs, which date from the last ice age. These water reserves were discovered in oil drilling in the 1950s. The goal of this project is to provide the population and agriculture in coastal areas and in proximity to pipelines with water. Furthermore, parts of the desert made ​​fertile, so that different plantations (eg date palms ) arise in the desert, irrigated by means of the GMMR project. Another goal is to extend as far as the farming in that also export of cultivation products is possible.

Effects

Prior to the infrastructure project, the tap water in the coastal region was burdened with a substantial, partly sickening salinity. In addition to improving the quality of drinking water is intended to expand with the water Libya to an agricultural exporting country. Feared - and in some cases have occurred - effects are the lowering of the groundwater table. Although the Ice water more than 300 meters below the earth's surface, it is not clear whether - as to some extent - a large area of the water table lying in 10 to 60 feet of water is affected.

Although co-initiated in the early stages of foreign engineers ( South Korean companies built factories, German developed the system know- how exchange ), now home to the entire world's largest project of its kind in purely Libyan hands. Libya sees this project as infrastructure and education factor.

The pipe segments of reinforced concrete are produced in two factories in Libyan Brega and Sarir. They are manufactured in accordance with the principle of prestressed concrete. This is required to withstand a water pressure of up to 60 bar.

In the initial phase, there were burst pipes of the pipeline. Had been omitted in the production of the pipe segments to an outer coating of the tubes. This allowed moisture to penetrate from the ground into the concrete. This had the consequence that the tension wire situated under the outer layer of concrete and the corroded tubes collapsed.

The fossil water in the various well fields is of very variable quality. Especially in the well field of Tazerbo the water with iron, manganese, and CO2 is heavily loaded. To avoid damage to the pipeline, own water treatment plants have been installed at the 108 wells. Each fountain and thus any water treatment system in this field has a capacity of 420 m³ / h Because of the huge dimension of the well field (1,000 km ²) and the immense capacity of 1.08 million m³ / day could not be used a centralized water treatment plant. Other well fields, as in Sarir, on the other hand do not require a water treatment plant and feed the pumped water directly into the pipeline one.

Central control

In a central office under the responsibility of the Great Manmade River Authority ( GMMRA ) the nationwide pipeline network is monitored. It is - technically sophisticated - intended to include all data supplied by sensors not only evaluate, but to also control each valve, each machine and all utensils centrally. Alternatively - eg power grid failures - can be made locally but also interventions.

Financing

Libya arose during the construction period a GMMR -Tax, which at least had to pay international air travelers as additional passenger taxes. In addition, most of the oil exports will have been a crucial source of funding.