South African Water Quality Guidelines




Back to	South African Water Quality Guidelines The South African Water Quality Guidelines are used as a basis for developing materials to inform water users about the physical, chemical, biological and aesthetic properties of water. It consists of the water quality criteria, the Target Water Quality Range (TWQR), and support information, such as the occurrence of the constituent in the aquatic environment, its effects on water uses, how these effects can be mitigated and possible treatment options. The TWQR for a particular water use is defined as the range of concentrations or levels at which the presence of the constituent would have no known adverse or anticipated effects on the fitness on the water assuming long-term continuous use, and for safeguarding the health of aquatic ecosystems. All the different TWQR for all the different water use sectors are dealt with in South African Water Quality Guidelines volumes one to seven. These include the guidelines for: Domestic Water Use (Volume 1), Recreational Water Use (Volume 2), Industrial Water Use (Volume 3), Irrigation Water Use (Volume 4), Livestock Watering (Volume 5), Aquacultural Water Use (Volume 6), Aquatic Ecosystem (Volume 7). The TWQR for all these water use sectors are summarised in Volume 8. Volume 1: South African Water Quality Guidelines - Domestic Water Use Domestic water refers to water that is used in domestic environment and also refers to all uses water can be put to in this environment. These include water for drinking, food and beverage preparation, hot water systems, bathing and personal hygiene, laundry and gardening. Domestic water users can experience a range of impacts like health, aesthetic and economic impacts as a results of changes in water quality. Water quality problems are associated with the presence of constituents and the interactions between them. The constituents like cadmium, chromium (VI), lead, mercury and vanadium can have either acute and/or irreversible effects on human health, even at low concentrations. As a precautionary measure, it is advisable not to use, for potable purpose, water containing these constituents, at concentrations above the TWQR. Volume 2: South African Water Quality Guidelines - Recreational Water Use Recreational water refers to all inland water which is used for recreational purposes. These include full contact recreation (swimming), intermediate-contact recreation (waterskiing and canoeing) and non-contact recreation like picnicking and hiking alongside water bodies. Recreational water users may experience a range of impacts as a result of changes in water quality. These include: health, aesthetic, economic impacts and human safety. Volume 3: South African Water Quality Guidelines - Industrial Water Use Industries are defined as systems of water-using processes, in which fitness for use of the water is assessed in terms of the following norms: its potential for causing damage to equipments (e.g. corrosion and abrasion) problems it may cause in the manufacturing process (e.g. precipitates and colour changes) impairment of product quality (e.g. taste and discolouration) complexity of waste handling as a result of using water of the quality available Volume 4: South African Water Quality Guidelines - Agricultural Water Use: Irrigation Irrigation water in these guidelines refers to water which is used to supply the water requirements of crops and plants which are not provided by rain, and refers to all uses water may be put to in this environment. This include water for: the production of commercial crops irrigation water application and distribution systems home gardening the production of commercial floricultural crops potted plants. Irrigation water users may experience a range of impacts as a result of changes in water quality. These may be categorised as follows: reduced crop yield as a result of increased salinity or the presence of constituents that are toxic to plants impaired crop quality; this may results in inferior products or pose health to consumers impairment of soil suitability as a result of the degradation of soil properties and accumulation of undesirable constituents or toxic constituents damage to irrigation equipment (corrosion or encrustation). Volume 5: South African Water Quality Guidelines - Agricultural Water Use: Livestock Watering The use of water for livestock production depends on several factors, such as the type of production system in use (intensive or extensive), the type of livestock and the type of livestock products. The potable quality of water for livestock may be defined according to the palatability of the water which would affect intake and hence production, as well as its degree of contamination with pathogenic micro-organisms, hydrocarbons, pesticides and salts such as nitrates, sulphates, fluoride and the salts of heavy metals. There are different impacts that may be experienced as a result of changes in water quality. These include: livestock consumption (toxicological and palatability effects) livestock distribution systems (economic impacts on the effects of scaling, corrosion or deposition of sediments in the distributing system) livestock product quality (consumer health hazards and product quality problems). Volume 6: South African Water Quality Guidelines - Agricultural Water Use: Aquaculture Aquaculture is aquatic agriculture and includes the husbandry, management, nutrition, genetics and controlled propagation of all aquatic organisms for use by humans. Aquaculture can be divided into several sectors: cage culture in dams or natural lakes extensive farming in small earthen farm dams extensive and semi-extensive fish farming in purpose designed fish ponds intensive farming in raceways and tanks. The greatest threat to freshwater aquaculture is industrial pollution of rivers, the effects of afforestation and deforestation on the water quality and quantity, the poor use of agricultural and riparian land, and of herbicides and pesticides. Volume 7: South African Water Quality Guidelines - Aquatic Ecosystems Aquatic ecosystems in these guidelines refer to the abiotic and biotic components, habitats and ecological processes contained within rivers and their riparian zones, reservoirs lakes and wetlands and their vegetation. Since the aquatic ecosystems serve as the resource base, they must be effectively protected and managed to ensure that water resources remain fit for agricultural, domestic, recreational and industrial uses on a sustainable basis. For the aquatic ecosystems guidelines, the TWQR is not a water quality criterion as it is for other water uses, but rather a management objective that has been derived from quantitative and qualitative criteria. Volume 8: South African Water Quality Guidelines - Field Guide All the different TWQR for all the different water use sectors dealt with in volumes one to seven are compiled in Volume 8. This volume serves as a quick and easy reference for comparison of the TWQRs for different water use sectors to determine the fitness of use for water and can always be used as a field guide. In all cases when using the Field Guide the user must refer back to the specific guideline for a particular water use sector and constituent as provided in a comprehensive guidelines, in order to obtain more detailed information to assess the fitness for use of water.