In terms of the National Health Act of 2003 (Act 61 of 2003), Water Quality Monitoring is a function of a District Municipality.
The Eden District Municipality (Eden DM) with an area of 23 331km² is a Category C – Municipality and comprises of seven local municipalities, namely George, Mossel Bay, Knysna, Bitou, Oudtshoorn, Hessequa and Kannaland. It is a legislative requirement that water services authorities and institutions must have suitable monitoring programmes in place for effective and efficient management of drinking water quality and this does include compliance monitoring. The term ‘water quality’ is generally used to describe the microbiological, physical and chemical properties of water that determine the fitness for the use of a specific water source.
Microbiological quality: Refers to the presence of organisms that cannot be individually seen by the naked eye, such as protozoa, bacteria and viruses. Many of these microbes are associated with the transmission of infectious water-borne diseases such as gastroenteritis and cholera. Faecal and total coliform bacteria are commonly used as indicator organisms to determine the microbiological status and safety of water supplies.
Physical quality: Refers to water quality properties (such as conductivity, pH and turbidity) that may be determined by physical methods. The physical quality mainly affects the aesthetic quality (taste, odour and appearance) of water.
Chemical quality: Refers to the nature and concentration of dissolved substances (such as organic and inorganic chemicals including metals). Many chemicals in water are essential as part of a person’s daily nutritional requirements, but unfortunately, most chemicals (e.g. zinc, copper, manganese) may have negative health effects when above a certain concentration.
The water quality monitoring function rendered by the Municipal Health Services section of Eden DM includes the following:
- Monitoring of water reticulation systems.
- Monitoring of quality and availability of water intended for human consumption, recreation or use by industries.
- Regular taking of water samples for analysis.
- Identification and control of sources of water pollution.
- Protection of water sources and resources by enforcement of legislation relating to water quality.
- Enforcement of legislation to ensure a supply of water which is safe for human health (Water Services Act, Act No 108 of 1997) and South African National Standards (SANS Code 241).
- Introduction of corrective and preventative actions (e.g. making recommendations to relevant authorities).
- Implementation of health and hygiene awareness actions and education relating to water supply.
Sampling frequency for a distribution system
If any changes in water quality are detected after the water has been through the treatment works, then the cause should be investigated. The sampling frequency should be increased until such time that the problem has been found and solved. It is proposed that the quality of the water in the distribution system and reticulation network should be determined on a monthly basis and increased to weekly samples if a water quality problem is found.
The water quality monitoring programme of Eden DM strives to provide accurate and consistent information to the public on drinking water quality. Microbiological, chemical and physical quality of drinking water is determined through sampling at different sources towards a “catchment to consumer” monitoring approach. Sources of sampling include boreholes, rivers, dams, reservoirs, water purification works and taps.
A preventative and risk-based approach is followed where risks that can compromise safe drinking water to communities are identified and reported to water services authorities and institutions to implement rectification measures towards unsafe and unhealthy conditions and health hazards.
Towns and locations in the Eden DM area where water samples are being taken on a monthly basis by Environmental Health Practitioners include:
Albertinia, Boggoms Bay, Brandwacht, Brenton, Brenton-on-Sea, Buffels Bay, Calitzdorp, De Rust, Dysselsdorp, Friemersheim, George, Gouritz, Great Brak Rivier, Haarlem, Heidelberg, Herbertsdale, Herolds Bay, Jongensfontein, Keurboomstrand, Knoetzie, Knysna, Kranshoek, Kurland, Kwanokuthula, Ladismith, Mossel Bay, Nature’s Valley, Oudtshoorn, Plettenberg Bay, Rheenendal, Riversdale, Sedgefield, Slangrivier, Still Bay, Uniondale, Van Wyksdorp, Victoria Bay, Vleesbaai, Wilderness, Witsand, Wittedrift and Zoar.
The Municipal Health Section’s drinking water quality monitoring programme facilitates closer working relationships between the District Municipality as a Drinking Water Quality Monitoring Authority and Water Services Authorities and has contributed to a Drinking Water System Blue Drop Performance Rating, ranging from very good drinking water quality management, exceptional drinking water quality management and platinum and gold awards that have been achieved in the Eden District municipal area in the past.