The Blyde River (i.e. Glad River), or Motlatse River (i.e. Permanent River), is a river in the Mpumalanga and Limpopo provinces of South Africa. It has a northwards course in steep-sided valleys and ravines of the Mpumalanga Drakensberg, before it enters the lowveld region of the Limpopo province. It has its ultimate origins at around 2,000 m altitude in the Hartebeesvlakte conservation area, to the north of Long Tom Pass. The Hartebeesvlakte, Mt Sheba Nature Reserve, Blyde River Canyon Nature Reserve and Blyde-Olifants Conservancy protect different sections of it.
Of the catchment area of 2,842 km², 220 km² is devoted to commercial forestry, and around 1,399 km² consists of indigenous forests.[1] Orchards and croplands were established along the lower Blyde in the latter half of the 20th century, with 23,521 ha devoted to irrigation in 1995.[1]
Blyde means "glad" or "happy"[2] in Dutch, and was thus named during a voortrekker expedition. The 'happy river' was so called in 1844, when Hendrik Potgieter and others returned safely from Delagoa Bay to the rest of their party of trekkers who had considered them dead. While still under this misapprehension they had named the nearby river where they had been encamped, Treurrivier, or 'mourning river'. The name Motlatse is claimed to predate the name Blyde, and means 'a river that is always full' in the sePulana dialect of Northern Sotho.[3][4]
The Treur River joins the Blyde at Bourke's Luck Potholes, in the canyon's upper reaches. The Ohrigstad River joins the Blyde River at the BlydeRivierpoort Dam in the Blyde River Canyon Nature Reserve of the Blyde River Canyon area. The Sandspruit is its only significant tributary in the lowveld.
The Klein Olifants, Steelpoort and Blyde Rivers are southern tributaries of the Olifants River, which enters the Kruger National Park and neighbouring private game reserves, eventually crossing the Mozambique border, where it flows into the Massingire Dam. The Blyde's average annual contribution to the Olifants is 436 million m3 of water,[1][5] a significant proportion due to the combination of relatively high precipitation and low evaporation in its catchment area.[1]