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Main
Rivers and tributaries |
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The 2 main tributaries of the
Buffels
River
are the Brak (41km) and the Riembreek rivers.
These two tributaries join to form the
Buffels
River
, approximately 149 km inland of the mouth.
Numerous other smaller tributaries join the stream before it
reaches the sea. (Ref 1)
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Although
the
Buffels
River
has the eighth largest catchment in the
Cape
, it only flows into the sea at times of exceptionally high rainfall.
(Ref 1
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Dams |
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River
run-off |
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The catchment fall within the winter
rainfall area and episodic floods occ ur occasionally (Heydorn and
Tinley 1980).
JAH Marais (1972) of the O'Kiep Copper
Company records that the main source of the Buffels river in the
Kamiesberg receives an average annual precipitation of 305
millimeters. The tributaries from the western "Bushmanland
peneplain" receive 102 mm and the Springbok mountain tributaries
178mm per annum. He goes on to say that "the Kamieskroon and
Springbok sectors of the catchment area fall within the winter rainfall
zone, whereas the Bushmanland peneplain enjoys only summer rainfall in
the nature of stormy downpours occasionally resulting in torrential
flowage of the river". According to Marais as well as Cornelissen
(1968) there is a three year rainfall cycle but a steady decline in
precipitation appears to have taken place sine 1953.
Charts obtained from the Agricultural
Technical Services' Extension officer in Springbok show that the Buffels
River source falls within an area with an annual precipitation of 201 -
250 mm/annum decreasing towards the coast which receives only
75-100mm/annum. (Ref 1)
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Geomorphology
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Most of the area around the mouth consists
of low scrub-covered dunes of windblown sand which overlie fossilised
aeolian dunes which show evidence of crossbedding in places.
Inland, outcrops of calcrete eroded by
marine terraces can be found and there is also evidence of strong
metamorphic action. (Ref 1)
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Geology
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The rocks in the area of the Buffels river
are known as the Buffels Marine Complex which is a name given to the
geological formations in the area by the DBCDM geologists at
Kleinsee. At the rivermouth these rocks belong predominantly to
the Namaqualand-Natal granite gneiss series (migmatite, gneiss,
ultrametamorphic rocks) which are seen as seaward dipping layered
formations of quartz, micacious gneiss and schists (De Beers
1979) (Ref 1)
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