Risks to Water Supply and Water Quality
The Stakeholder Accord on Water Conservation of the Fund for Research into Industrial Development, Growth and Equity (Trade and Industry Chamber, 2009:i-vi) identifies the following major water quality risks:
1 Eutrophication of surface waters
Eutrophication emerges largely from fertiliser and livestock waste, inadequate wastewater treatment and sanitation infrastructure, as well as household waste, which leaches or runs off into the natural water resources. This results in algal blooms, which disrupt water transfer and irrigation systems, and increased toxicity of water associated with higher nutrient levels and the type of algae prevalent in such blooms.
2 Heavy metal contaminationHeavy metal contamination poses a significant risk to drinking water quality and, consequently, human and animal health. Studies have shown this to emanate largely from the mining sector.
3 Acid mine drainageAlso related to coal and gold mining activity, acid mine drainage, which results from the oxidisation of iron sulphide, raises the acidity and salinity of water. The contamination has negative effects on water quality and thus human and animal health, and also on industrial activity. Polluted water in the Witbank and Middelburg Dams has been rising, risking usability for electricity generation. To circumvent this, water has been pumped from nearby rivers to dilute the effluent. Acid mine drainage is particularly prevalent on the Witwatersrand and in Mpumalanga.
Stakeholders have acknowledged the risks of acid mine drainage, however implementation of measures to reduce it have been slow.
4 Increases in salinitySalinity, a natural consequence of groundwater discharge and geological leaching, is exacerbated by mining, agricultural and industrial activity. This has adverse impacts on the quality of drinking water, as well as on soil quality.
5 Increased levels of suspended solids
High levels of suspended solids have potentially significant ecological impacts, and are mostly caused by land use practices in mining, agriculture and human settlement activities.
6 Bacterial and viral pathogens
Bacterial and viral pathogens raise the vulnerability of people, especially children and the elderly, to various diseases. These risks arise mostly from inadequate access to sanitation and problems with waste water treatment. This is concomitant with a sharp increase in urbanisation which has added to the historical backlog, placing access to municipal services under pressure and highlighting the desperate need for additional infrastructure.
According to the 2009 Green Drop report, 55 per cent of South Africa‟s waste water treatment plants need attention, and only seven per cent conform to Green Drop status requirements.
See the full water report by visiting: http://www.polity.org.za/article/the-south-african-water-crisis-an-economic-impact-study-november-2010-2010-11-16
