The foggara in Algeria: A hydraulic world heritage
Located in arid regions, the foggara in Algeria, the Qanat in Iran, Khettara in Morocco and Falj in Oman, are a system used for the acquisition and distribution of water, based on horizontal drainage galleries. However, although there are similarities in their collection system (galleries and shafts), these traditional techniques show differences in their water source and in the technique of water sharing. Through this study, based on prospecting trips in five oases of the Algerian Sahara and investigations at the oases, we could identify seven types of foggara, namely: those that receive water from the water table at the foot of a mountain range; those that drain the waters of the intermittent streams; which receive waters from the “Continental Intercalaire” aquifer; which receive water from a spring; which receive the waters from the Occidental Great Erg aquifer; which capture drainage and infiltration; and finally those that capture only flood waters (foggara of Mzab).