This article discusses the topic of foggara of Moghrar. For more than seven centuries, thousands of palm trees are irrigated by this foggaras. On the basis of missions in the oasis of Moghrar during the years 2006, 2009, 2013 and 2015 to understand the functioning of the traditional hydraulic system. The foggara of Moghrar is powered from a water source. Equipped with a gallery of 300 m in length and a single aeration wells, the foggara of Moghrar is used for irrigation of the palm grove. Even with the addition of pumps, the foggara continues to function despite the decrease of water flow.