Rationale for River Health Monitoring
There is a huge potential for development on water resources monitoring in Angola. Monitoring of river health needs to be amongst the early priorities. The reasons for this are both environmental and socio-economic:
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River health reflects the robustness and diversity of aquatic and riparian ecosystems, and Angola has made international commitments to biological diversity (GoA 1998a);
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The Kunene River, although modified by man, has sections that are close to ‘pristine’ from an ecological perspective and this should be preserved;
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A healthy river provides essential ecosystem services such as food, potable water, water for irrigation, water purification and regulation, amenity and spiritual value (MEA 2003);
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River health monitoring provides information to allow sustainable abstraction and the maintenance of environmental flows.
River health monitoring comprises the observation of key physical, chemical and biological parameters in order to characterise the health of the watercourse.
Building improved latrines for improved river health.
Source: Tump 2007
( click to enlarge )
International Best Practice – The European Water Frame Directive (WFD)
One of the most advanced systems of river health monitoring in the world is probably the one given by the European Water Framework Directive (EC 2000). This requires Member States of the European Union to gather data on their surface and groundwater bodies, and to put in place a programme of measures to improve the ecological status of these water bodies by a certain date.
Characterisation of European water bodies consists of four ‘Ecological status’ components:
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Physico-chemical (e.g. nutrients, pH, dissolved oxygen, ammonia);
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Biological (e.g. phytoplankton, macroalgae, fish, invertebrates);
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Specific Pollutants (e.g. metals and their compounds, organic compounds); and
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Hydromorphology (e.g. depth, width, flow, structure).
Besides these a fifth component, ‘Chemical status’, is considered:
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Monitoring of priority substances which present a significant risk to the water environment.
In summary, these five elements characterise the Overall Status of a European water body.
It may not be appropriate to transpose this kind of system to the current Angolan and Namibian context. However, the logic behind it may be useful for the design of river health monitoring systems for the Kunene basin, where an appropriate River Health Monitoring system is yet to be implemented.
A model for such system could also be the Integrated Framework for Wetland Health Monitoring in Dryland Namibia, proposed by the Wetlands Working Group of Namibia, the National Biodiversity Programme and the Directorate of Environmental Affairs of the Ministry of Environment and Tourism (Bernard et al. 2002).
