Wadi

Hydrological feature

A wadi ( WOD-ee; Arabic: وَادِي) is a river valley or a wet (ephemeral) riverbed that typically contains water only when heavy rain occurs, though wadis with year-round water flow do exist, such as Wadi Bani Khalid and Wadi Mawr. Wadis are located on gently sloping, nearly flat parts of deserts; commonly they begin on the lowest portions of alluvial fans and extend to inland sabkhas or dry lakes. Permanent channels rarely exist, due to lack of continual water flow.

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