The massive underground river feeding Libya's thirsty northern coast

Countries & Cities · Published 30 September 2026 Swipe more like this →

In short: To sustain its populous Mediterranean cities, Libya constructed the world's largest irrigation project. This vast network of pipes taps into ancient, non-renewable water stores deep beneath the Sahara, transporting life-sustaining liquid across 1,600 kilometers to provide the majority of the nation's fresh water.

Conceived in the late 1960s and begun in 1984, the Great Man-Made River Project (GMRP) is a colossal feat of engineering. It functions by pumping water from the Nubian Sandstone Aquifer System—a fossil aquifer that accumulated during the last ice age—to cities like Tripoli and Benghazi. This underground network spans roughly 2,820 kilometers and utilizes more than 1,300 wells, many of which descend over 500 meters into the earth.

The project's scale is immense. It provides approximately 6,500,000 cubic meters of fresh water every day, accounting for 70% of Libya's total fresh water usage. While the late Muammar Gaddafi famously referred to it as the "Eighth Wonder of the World," the project's reliance on fossil water makes it a subject of intense debate. Because this water is not being replenished, its longevity is uncertain. Some estimates suggest the aquifer could last a millennium if extraction rates remain steady, while others warn it could be depleted in as little as 60 to 100 years.

The infrastructure has also become a focal point of conflict. During the First Libyan Civil War in 2011, a pipe-manufacturing plant in Brega was destroyed by a NATO air strike. Later, during the Second Libyan Civil War (2014–2020), the system suffered from neglect and damage. In April 2020, the seizure of a water control station near Tripoli left over two million people without water, an act condemned by the United Nations on humanitarian grounds.

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