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

Most of the clayey loam soils in the upper parts of the sub-catchment are suitable for irrigation when sufficient
water is available. There are two small portions of formal irrigation board control areas in the upper part of the
sub-catchment, with two more small irrigation areas in the central reaches. The area along the banks of the
Limpopo River is part of a formal irrigation area, and uses water that is pumped either from the bed of the
Limpopo River or from boreholes sunk next to the riverbed. Further away from the main river channel, the land
use consists almost entirely of small-scale livestock farming as well as the raising of game animals.
A few small towns and several small settlements are present in the upper reaches of the sub-catchment, though
population densities decline with increasing distance downstream. The northern and eastern portions of this
sub-catchment support large numbers of small-scale subsistence farmers.
4.16.1.4 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. Most of the water used in the sub-catchment is consumed by the extensive formal irrigation along
the Laphalala River. The sub-catchment has very unreliable supplies of water and there is little opportunity to
expand the irrigated areas without importing additional water supplies (Midgley et al., 1999).
The large numbers of subsistence farmers in the northern 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
Mogalakwena sub-catchments in an attempt to alleviate the hardships experienced by these residents.
4.16.1.5 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 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 Laphalala River. 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.
4.16.1.6 Human impacts on water resources (excluding mining)
The following activities can be expected to have an impact on water resources in the Laphalala sub-catchment:
• Minor seepage from small landfill sites and solid waste disposal sites at towns;
• Disposal of liquid (domestic) effluent at towns;
• Minor volumes of urban runoff from towns;
• Non-point domestic effluent from numerous small settlements and farms;
cclxi