OVERVIEW OF THE IMPACT OF MINING ON THE ... - IIED pubs

No water quality data for this sub-catchment could be obtained in time for inclusion in this report.
5.9.6 Implications for water quality and quantity management
The alluvial gold mining activities in this sub-catchment are the only ones likely to have any implications for
water quality. The rocks of the Giyani Greenstone Formation contain deposits of arsenopyrite and the artisan
gold miners also use mercury to separate out the gold. Therefore, there is a small possibility that arsenic and
mercury may pose localized problems in the upper reaches of this sub-catchment.
5.10 The Timbavati-Klaserie sub-catchment
5.10.1 General description
5.10.1.1 Hydrology
This sub-catchment consists of the lowest portion of the Olifants basin in South Africa and contains the area
drained by the Timbavati and Klaserie rivers, as well as the Nhlaralumi and several smaller tributary streams
(Figure 4.2). The Klaserie River rises on the eastern slopes of the Drakensberg Mountains, whilst the
Timbavati Rivers rises in the foothills of the Drakensberg Mountains. The other tributary streams rise from
outcrops of low granitic hills scattered across the Lowveld within the boundaries of the Kruger National Park
(KNP). The Klaserie River is perennial only in its upper reaches and most of its water is lost by evaporation or
abstraction for irrigation. Apart from the Klaserie River, all the other rivers and streams have episodic flows only
during the wetter summer months. Overall, the predominantly episodic tributary rivers in this sub-catchment do
not provide very large quantities of water to the Olifants River.
Most of the catchment area of the Timbavati and Klaserie rivers and their tributaries lies within the boundaries of
the KNP, with a small portion located between the foot of the Drakensberg Mountains in the west and the
western boundary of the KNP. There are several small farm dams located in the headwater zones of the
Timbavati and Klaserie rivers outside the KNP, as well as one larger water supply impoundment on the Klaserie
River. Most farms outside the KNP and the tourist camps inside the KNP rely on boreholes for their water
supplies, particularly during the dry winter months of the year.
5.10.1.2 Geology
The geological features of the Timbavati – Klaserie sub-catchment are similar to those of the Shingwedzi subcatchment.
Most of the area is underlain by large areas of granitic and gneissic rocks of the crystalline
Basement Complex, with the acidic and intermediate rhyolites and lavas of the Karoo Sequence to the east
forming the northern extension to the Lebombo Mountains. In the western portion of the sub-catchment, rocks
of the Transvaal Sequence forming the Drakensberg Mountains underlie the western edges of the area drained
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