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

• Dark grey to blackish, mottled vertisols located along low-gradient reaches of most streams and river
sections, forming characteristic wetland soils.
Most of the clayey loam soils are highly suitable for commercial agriculture when sufficient water is available.
Virtually all of the areas with suitable soils, particularly the area downstream of the Bronkhorstspruit Dam, are
contained within the jurisdiction of formal irrigation boards or Government Water Control Areas. Further away
from the main river channels, most of the land use is given over to small- and medium-scale livestock farming
operations. A relative small variety of crops are produced on the irrigated and rain-fed areas, primarily maize,
Lucerne, potatoes and sunflowers. Minor areas of plantation forestry (principally Wattle) are also located in the
wetter portions of the sub-catchment.
Several small towns (e.g. Bronkhorstspruit and Cullinan) and numerous smaller settlements and farming
communities are present in the upper reaches of the sub-catchment. Population numbers and density decline
with increasing distance from the upper reaches. Some light and heavy industry is present in the town of
Bronkhorstspruit, with many industries geared specifically to meeting the needs of the extensive mining sector in
the region.
5.2.1.4 Surface water users
All towns in the sub-catchment rely on water supplied from water supply reservoirs, principally the
Bronkhorstspruit Dam and, in the case of Cullinan, from the Rand water reticulation system. The larger
settlements are also being supplied with water to varying degrees by the Rand Water reticulation system.
Smaller settlements and farmsteads rely on boreholes for their water requirements. The Wilge and Kendal
thermal power stations are also supplied with water drawn from local water supplies.
The extensive irrigation areas downstream of the Bronkhorstspruit Dam consume most of the water used in the
sub-catchment. Extensive informal settlements have sprung up around the periphery of the urban centres;
these settlements lack access to basic services such as clean water supplies and suitable sanitation systems.
5.2.1.5 Water management systems
The South African Department of Water Affairs and Forestry (DWAF) is responsible for the management of all
aspects of water supply and water use in the sub-catchment. The Department operates a system of routine flow
gauging at the Bronkhorstspruit Dam and pays particular attention to monitoring the quantity of water supplied to
irrigation schemes and towns, as well as increasing attention to the quality of agricultural return flows and
effluent discharges to the Wilge River. The local irrigation board is responsible for the day-to-day management
of water allocations for irrigation.
5.2.1.6 Human impacts on water resources (excluding mining)
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