The main rivers of the Catchment are the Mefou itself and its main tributaries, which are the Zamengoé, the Nkoi, the Afeumev and the Benyam. The source of the Mefou River is located in the Mt Mbam Minkom area. Having a total length of 121 km, the Mefou joins the Nyong at Odou. A major tributary of the Mefou is the Mfoundi, which is the main drainage of Yaoundé. An important feature of the Upper Mefou (aka Mopfou) is a dam, constructed in 1969 and currently under reconstruction.
The Mefou reservoir (fr. Barrage du Mefou) has a surface of 105 ha, a maximum length of 13 km and a volume 7 million m³. It is located at an altitude approximately 721 m. a.s.l. Between 1976 and 2005 the reservoir was abandoned but the dam wall has been under reconstruction since August 2011. It has an average height of 17.5 m and an average length of 225 m. The water stored in the reservoir will contribute to the freshwater supply of Yaoundé.