The Oued Bou Sellam receives the wadi Malah, taking its source to Aïn Arnat in the dam Aïn Zada. After crossing the Aïn Zada dam, it crosses the Khelil commune by the east and receives two new tributaries, Wadi Khelil, which flows from the left bank in Besbassa halfway between El Kherba and the Aïn Zada dam and the wadi Taissa shortly before on the right bank.