Semefé River

Bakoy River
Map of the Sénégal River drainage basin
Country	Guinea, Mali
Physical characteristics
Main source	Monts Ménien in northeast Guinea 760 m (2,490 ft) 11°50′N 9°45′W / 11.833°N 9.750°W / 11.833; -9.750
River mouth	Sénégal River at Bafoulabé 83 m (272 ft) 13°48′50″N 10°49′41″W / 13.81389°N 10.82806°W / 13.81389; -10.82806Coordinates: 13°48′50″N 10°49′41″W / 13.81389°N 10.82806°W / 13.81389; -10.82806
Length	560 km (350 mi)
Discharge	Average rate: 156 m3/s (5,500 cu ft/s)
Basin features
River system	Sénégal River
Basin size	85,600 km2 (33,100 sq mi)
Tributaries	Right: Baloué 13°32′58″N 9°54′35″W / 13.54944°N 9.90972°W / 13.54944; -9.90972

The Bakoy or Bakoye River is a river in West Africa. It runs through Guinea and Mali and joins with the Bafing River to form the Sénégal River at Bafoulabé in the Kayes Region of western Mali. In Manding languages, Bakoye signifies 'white river', Bafing 'black river' and Baloué 'red river'.

The source of the Bakoy is at an elevation of 760 m in the granite Monts Ménien to the northwest of Siguiri in Guinea. The river flows north and forms part of the international border between Guinea and Mali. It then meanders across the Manding Plateau and joins its principal affluent, the Baloué, which rises to the west of Bamako. The Bakoy is 560 km in length and drains a basin of around 85,600 km². The river is seasonal with a maximum flow in September after the start of the West African Monsoon and almost no flow between January and June. The large year-to-year variation in the intensity of the West African Monsoon gives rise to large changes in the discharge of the Bakoy River. For the exceptionally dry year of 1972, the average flow at the Oualia gauging station, 54 km upstream of Bafoulabé, was only 30 m³/s while in 1958 the value was 260 m³/s. The average flow over the period 1951-1978 was 156 m³/s corresponding to an annual discharge of 4.9 km³. At Bafoulabé the average discharge of the Bakoy is between a third and a half of that of the Bafing.