Wadi Derna is a river valley in

Libya Libya (; ar, ليبيا, Lībiyā), officially the State of Libya ( ar, دولة ليبيا, Dawlat Lībiyā), is a country in the Maghreb region in North Africa. It is bordered by the Mediterranean Sea to the north, Egypt to Egypt–Libya bo ...

which leads down from the Jebel Akhdar mountains to the port city of Derna. Like many other

wadi Wadi ( ar, وَادِي, wādī), alternatively ''wād'' ( ar, وَاد), North African Arabic Oued, is the Arabic term traditionally referring to a valley. In some instances, it may refer to a wet (ephemeral) riverbed that contains water onl ...

s in

North Africa North Africa, or Northern Africa is a region encompassing the northern portion of the African continent. There is no singularly accepted scope for the region, and it is sometimes defined as stretching from the Atlantic shores of Mauritania in ...

, it is an

intermittent Intermittency is a behavior of dynamical systems: regular alternation of phases of apparently periodic and chaotic dynamics. Intermittent or intermittency may also refer to: *Intermittent river or stream, the one that ceases to flow every year or ...

riverbed A stream bed or streambed is the bottom of a stream or river (bathymetry) or the physical confine of the normal water flow (channel). The lateral confines or channel margins are known as the stream banks or river banks, during all but flood st ...

that for much of its length contains water only when heavy

rain Rain is water droplets that have condensed from atmospheric water vapor and then fall under gravity. Rain is a major component of the water cycle and is responsible for depositing most of the fresh water on the Earth. It provides water f ...

occurs. It is long and drains a

drainage basin A drainage basin is an area of land where all flowing surface water converges to a single point, such as a river mouth, or flows into another body of water, such as a lake or ocean. A basin is separated from adjacent basins by a perimeter, t ...

of 575 km.

Derna waterfalls

The

Derna waterfalls Derna waterfalls ( ar, شلال درنة) is a fresh water waterfall A waterfall is a point in a river or stream where water flows over a vertical drop or a series of steep drops. Waterfalls also occur where meltwater drops over the edg ...

are located in Wadi Derna about 7 km (4.3 mi) to the south of Derna.

2023 Derna catastrophe

In September 2023, against the backdrop of the civil war, the rainfall from the

Storm Daniel Storm Daniel, also known as Cyclone Daniel, was the deadliest Mediterranean tropical-like cyclone in recorded history, as well as one of the costliest tropical cyclones on record outside of the north Atlantic Ocean. Forming as a low-pressure s ...

led to the collapse of two dams across the river, the Derna dam and the Abu Mansour dam, causing catastrophic flooding in the city of Derna, which killed at least 4,000 people. It was one of the deadliest dam failures in history.

References

{{DEFAULTSORT:Wadi Derna Derna