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

oth light and heavy industry is present in the cities and larger towns, with many industries geared specifically to
meeting the needs of the extensive mining sector.
4.14.1.4 Surface water users
All cities, towns and settlements in the sub-catchment rely on water supplied from the larger water supply
impoundments, or from run-of-river abstraction points and, occasionally (in the lower reaches), from local
boreholes. Most of the water used in the sub-catchment is consumed by the extensive urban areas that are
spread across the headwaters of the sub-catchment, whilst the numerous irrigation schemes in the Government
Water Control Areas along the Crocodile River and its major tributaries also require very large volumes of water.
Water supplies are supplemented by water imported from the Vaal River system to the south of Johannesburg;
this water is used primarily for domestic and industrial use. Extensive informal settlements have sprung up
around the periphery of the major urban centres. These settlements lack access to basic services such as
clean water supplies and suitable sanitation systems.
The extensive mining developments in the mineral-rich Bushveld Igneous Complex compete with irrigation
agriculture in the sharing of the relatively meagre water resources that are available (Midgley et al., 1995).
Historically, irrigation development preceded the more recent emphasis on mining of chrome, platinum-group
minerals, iron ore, phosphates, fluorspar and coal. Unless the water supplies to large areas under irrigation can
be “cannibalised”, additional supplies of water will need to be imported into this sub-catchment to meet the
rapidly rising demands for water that result from continued mining development and the possible construction
and operation of future coal-fired power stations (Midgley et al., 1995).
4.14.1.5 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 comprehensive
system of flow gauging at all dams in the sub-catchment and particular attention is paid 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 Crocodile River.
This sub-catchment (and its western neighbour, the Marico River sub-catchment) are likely to become the first
official Catchment Management Agency that will take over responsibility for al aspects of water resource
management and water supply. The preliminary documentation is being finalized and catchment studies are
either in progress or have already been completed.
4.14.1.6 Human impacts on water resources (excluding mining)
The following activities can be expected to have an impact on water resources in the sub-catchment:
• Landfills and solid waste disposal sites at all cities and towns;
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