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

the Limpopo River some 100 kilometres downstream of the confluence of the Bonwapitse and Limpopo rivers.
The river is normally seasonal and only carries surface water during the summer months.
The Lotsane River has a small water supply dam near the town of Palapye and this provides the main source of
domestic water for the town, as well as water drawn from the North-South Pipeline. Several small farm dams
and boreholes provide water for stock watering in several parts of this dry sub-catchment.
4.3.1.2 Geology
The rocks of the Kalahari Craton underlie this sub-catchment. Large areas of the sub-catchment have
exposures of Gaborone and Mahalapye granites, as well as rocks of the Palapye Suite and the Lebung
Formation of the Karoo System. The Karoo System rocks in the area contain economic sources of coal.
4.3.1.3 Pedology, agriculture and land use
Soils in the sub-catchment can be divided into five groups:
• Moderately shallow, coarse-grained feldspathic to kaolinitic sands, derived from the Gaborone and
Mahalapye granites;
• Moderately shallow sandy loams, formed from gneisses; and
• Shallow, clay-rich soils with high sodium content in internally draining areas.
The sub-catchment receives low and unreliable rainfalls (under 500 mm per year) with high evaporation rates.
Soils are generally shallow and poor to medium quality. Areas with high sodium content pose a salinization risk
for irrigation schemes. Soils become progressively sandier towards the eastern portion of the sub-catchment as
rainfalls decline and evaporation rates increase.
Land use in the sub-catchment consists mostly of small-scale commercial and subsistence farming of drought
resistant crops, as well as livestock rearing of goats and donkeys. The main settlements are the towns of
Serowe, Palapye, Mokoro and Maunatlala, with numerous smaller settlements located along the North-South
Pipeline route and along the many roads traversing the sub-catchment.
4.3.1.4 Surface water users
All towns and settlements rely on whatever surface water they can obtain from the seasonal flows in local
streams and rivers, as well as an extensive system of boreholes. Larger towns such as Serowe and Palapye
obtain most of their water from the North-South Pipeline as well as from local boreholes. Small areas of
irrigation rely on local boreholes for their water supplies.
4.3.1.5 Water management systems
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