While society has long focussed on water quantity - maintaining dam volumes, streamflow, water supply, etc. - water quality has been largely ignored, especially in terms of policy instruments to enable and empower authorities to protect and manage this critical aspect of freshwater (Hattingh and Claassen 2008). The first movements in this direction in southern Africa occurred in 1961 when the South African government implemented effluent guidelines and eventually special effluent standards (DWAF 1991).
The overall water quality situation in the Limpopo River basin is described as impacted, but not severe (LBPTC 2010). Land use management practices and developments within this basin have altered water quality when compared with the baseline or unimpacted conditions.
According to a study by Ashton et al. (2001), water resources in most of the sub-catchments in the Limpopo River basin are impacted by the following:
Mining and minerals processing.
Landfills and solid waste disposal sites.
Disposal of liquid and effluent.
Non-point domestic effluent via soak-aways in rural areas.
Non-point impact of irrigation and redistribution of river waters.
Non-point impact from commercial or subsistence agriculture.
Fuel loss and litter on roadways.
In fact, the Olifants River in the South African portion of the Limpopo River basin has been described as one of the most polluted rivers in southern Africa. This is the subject of a study being undertaken by the CSIR (South Africa) in the Upper Olifants River.
These sources of impact and others will be looked at in the following sections in relation to:
