Water quality generally deteriorates moving down a river course. However, the quality of the Kunene River from source to mouth is relatively unpolluted and is considered to be good (ERM 2009). This is mainly due to a limited anthropogenic influence from urban areas, agriculture, industry and the mining sector. However, Angola is increasing efforts to exploit its enormous potential in natural resources. A poorly managed and rapid development in some economic sectors could be seen as non-sustainable and prove to be a reason for concern about the future water quality of rivers and aquifers.
The Upper Kunene system generally provides high quality water, but due to a relatively high population density particularly in and around Huambo, the potential of water pollution from urban/rural domestic sources is higher than in any other part of the basin. Following the river course further downstream effluents of irrigated agricultural enriches the water with nutrients and other agro-chemicals. Thanks to the natural filtering effects of the vast wetlands in the Middle Kunene, north of the Calueque dam, and a very sparsely populated Lower Kunene basin at the border with Namibia, the quality of the river water remains good until it reaches the Atlantic.
In areas where there is a significant potential for human impacts on the Kunene River the key water quality issues to be monitored:
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Eutrophication;
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Microbiological organisms and water-borne pathogens;
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Heavy metals;
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Persistent organic pollutants (POPs); and to a lesser extent; and
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Temperature changes through storage of water in huge reservoirs.
This chapter will look more closely at human impacts on water quality with a focus on:
Human impacts can alter water quality and ultimately entire ecosystems.
Source: Vogel 2003
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