The Great Man-Made River (GMMR, النهر الصناعي العظيم) is a network of pipes that supplies fresh water obtained from the Nubian Sandstone Aquifer System fossil aquifer across Libya. It is the world’s largest irrigation project. The project utilizes a pipeline system that pumps water from the Nubian Sandstone Aquifer System from down south in Libya to cities in the populous Libyan northern Mediterranean coast including Tripoli and Benghazi. The water covers a distance of up to 1,600 kilometers and provides 70% of all freshwater used in Libya.
According to its website, it is the largest underground network of pipes (2,820 kilometres (1,750 mi)) and aqueducts in the world. It consists of more than 1,300 wells, most more than 500 m deep, and supplies 6,500,000 m3 of fresh water per day to the cities of Tripoli, Benghazi, Sirte and elsewhere. The late Libyan Leader Muammar Gaddafi described it as the “Eighth Wonder of the World”.
In 1953, efforts to find oil in southern Libya led to the discovery of large quantities of potable fossil water underground. The Great Man-made River Project (GMRP) was conceived in the late 1960s and work on the project began in 1984. The project’s construction was divided into five phases. The first phase required 85 million m³ of excavation and was inaugurated on 28 August 1991. The second phase (dubbed First water to Tripoli) was inaugurated on 1 September 1996.
The project is owned by the Great Man-Made River Project Authority and was funded by the Gaddafi government. The primary contractor for the first phases was Dong Ah Consortium and the present main contractor is Al Nahr Company Ltd.
The imported goods were made in Korea and destined to the construction of the GMR arrived by sea via the entry port of Brega (Gulf of Sidra). Cathodic corrosion protection on the pipeline was supplied by an Australian company, AMAC Corrosion Protection, based in Melbourne and delivered via Port of Benghazi. The rest of goods were made in Libya.
The total cost of the project is projected at more than US$25 billion. Libya has completed the work to date without the financial support of major countries or loans from world banks. Since 1990 UNESCO has provided training to engineers and technicians involved with the project.
The fossil aquifer from which this water is being supplied is the Nubian Sandstone Aquifer System. It accumulated during the last ice age and is not currently being replenished. If 2007 rates of retrieval are not increased, the water could last a thousand years. Independent estimates indicate that the aquifer could be depleted of water in as soon as 60 to 100 years. Analysts say that the costs of the $25 billion groundwater extraction system are 10% those of desalination.
In this project 1 billion euros were invested for the installation of 50,000 artificial palm trees for water condensation. This project was carried out by the Spanish engineer Antonio Ibáñez de Alba.
On 22 July 2011, during the first Libyan civil war, one of the two plants making pipes for the project, the Brega Plant, was hit by a NATO air strike. At a press conference on 26 July, NATO claimed that rockets had been fired from within the plant area, and that military materiel, including multiple rocket launchers, was stored there according to intelligence findings, presenting a photo showing a BM-21 MRL as an example.
During the second Libyan civil war, lasting from 2014 to 2020, the water infrastructure suffered neglect and occasional breakdowns. As of July 2019, 101 of 479 wells on the western pipeline system had been dismantled.
On 10 April 2020, a station controlling water flow to Tripoli and neighboring towns was seized by an unknown armed group. The flow of water was cut to over two million people as a result, and as such the attack was condemned by the United Nations on humanitarian grounds.