Foggara is the traditional underground irrigation channel system used in Sahara oases.
Foggaras are gently sloping subterranean tunnels that collect groundwater and carry it toward cultivated land. Vertical access shafts, spaced along the route, allow construction, ventilation, inspection, and maintenance. The system uses gravity rather than pumps, making it especially valuable in extremely dry environments.
Foggaras are particularly associated with Algeria’s Saharan oases, including the regions around Adrar and Gourara. Related systems have different names elsewhere, such as qanat in Iran and khettara in Morocco, although their basic principles are similar.
A foggara is not simply a well or an open canal. It is a carefully engineered water-conveyance network whose small, controlled flow can support date palms, gardens, and settlements. Modern pumping has reduced the importance of many foggaras, but surviving systems remain important examples of traditional desert engineering.