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

4.18.1.4 Surface water users
All of the towns and settlements in the sub-catchment rely on water supplied from numerous small water supply
impoundments, or from run-of-river abstraction points and, occasionally (in the lower reaches), from local
boreholes. The extensive areas of irrigation along the Mogalakwena River consume most of the water used in
the upper and central reaches of the sub-catchment. The sub-catchment has very unreliable supplies of water
and the Magalies Water Board provides additional water supplies via a pipeline from Pretoria.
The large numbers of subsistence farmers in the central and eastern portion of the sub-catchment rely on
boreholes and hand-dug wells for their water supplies. The Department of Water Affairs and Forestry is
undertaking a concerted campaign to provide water supplies to these and other nearby areas in the Mokolo and
Laphalala sub-catchments in an attempt to improve the reliability of their water supplies.
4.18.1.5 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 routine system of flow
gauging at all major water supply 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 any effluent discharges to the Mogalakwena River. Extensive surveys of the subcatchment’s
ground water potential have been carried out by DWAF so as to facilitate selection of appropriate
locations for water supply boreholes.
Irrigation Boards are locally responsible for providing allocations of water to their members, though they are not
responsible for the quality of the water supplied or for the quality of any irrigation return flows that seep back to
nearby watercourses.
4.18.1.6 Human impacts on water resources (excluding mining)
The following activities can be expected to have an impact on water resources in the Mogalakwena subcatchment:
• Minor seepage from small landfill sites and solid waste disposal sites at several of the larger towns;
• Disposal of liquid (domestic and some light industrial) effluent at all towns;
• Minor volumes of urban runoff from the larger towns;
• Non-point domestic effluent from numerous small settlements and farms;
• Minor non-point impact from non-intensive subsistence agriculture;
• Non-point impacts of agricultural return flows from intensive irrigation areas; and
• Litter and domestic garbage discarded alongside the extensive road system that traverses the subcatchment.
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