At a basin or sub-basin scale, particularly in semi-arid and arid areas, priority is often placed on monitoring and management of water quantity. Equally important, however, is the monitoring and management of water quality (DWAF 2004). Water quality is often characterised in terms of the concentration of different chemicals in the water (Hatfield 2008).
What determines “good” or “bad” water quality depends on the purpose of the assessment—for example, water with naturally elevated concentrations of some metals may be unsafe to drink, but still suitable for industrial uses. Assessment involves comparing measured chemical concentrations with natural, background, or baseline concentrations, and with guidelines established to protect human health or ecological communities. Below is a summary of key findings from water quality studies for the Limpopo River basin.
This chapter describes how physical, chemical, biological and qualitative indicators are used to come to the conclusions below and what human activities are most likely to contribute to the water quality problems in the basin.
Chapter Summary
This chapter covers the following concepts and materials:
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The principles of water quality, including the physical, chemical, and biological characteristics
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The impacts of human activities on water quality
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The concept of fitness for use
Sunset in the Waterberg, an area under threat from water quality issues related to power generation.
Source: Andre 2008
( click to enlarge )
Monitoring of water quality is discussed in more detail in the Resource Management theme, under the Existing Monitoring chapter.
