WATER QUALITY: CONTAMINATION AND PROTECTION

1. Water Quality Microbiological Quality: Microbiological Quality: Presence of organisms that cannot be seen by the naked eye – faecal and total coliforms Presence of organisms that cannot be seen by the naked eye – faecal and total coliforms Physical Quality Physical Quality Affecting taste, odour and appearance. pH, Turbidity etc. Affecting taste, odour and appearance. pH, Turbidity etc. Chemical Quality Chemical Quality Nature and concentration of dissolved substances. E.g salts, organics, etc. Most of these are essential, but in high quantities may cause problems. Nature and concentration of dissolved substances. E.g salts, organics, etc. Most of these are essential, but in high quantities may cause problems.

2. Common Water Quality Problems: Surface Water Faecal Pollution Faecal Pollution High faecal and total coliform counts –near dense human settlements High faecal and total coliform counts –near dense human settlements Colour and Stability Colour and Stability Due to organic acids Due to organic acids Salt Concentrations (TDS) Salt Concentrations (TDS) High sulphate and chloride concentrations. Corrosive and distinctly salty High sulphate and chloride concentrations. Corrosive and distinctly salty

2. Common Water Quality Problems: Surface Water Eutrophication Eutrophication High nutrient concentration (nitrogen, phosphate) and high algal concentrations. High nutrient concentration (nitrogen, phosphate) and high algal concentrations.

3. Common Water Quality Problems: Groundwater Salinity Salinity Occurs where the predominant geological formations are sedimentary rocks of marine origin. Eg. The Karoo Occurs where the predominant geological formations are sedimentary rocks of marine origin. Eg. The Karoo Fluoride Fluoride Especially in the coal bearing regions (central and western parts of the country) Especially in the coal bearing regions (central and western parts of the country) Sulphate and Chloride Sulphate and Chloride Especially water with high TDS Especially water with high TDS

3. Common Water Quality Problems: Groundwater Calcium and Magnessium Calcium and Magnessium Especially in dolomitic areas Especially in dolomitic areas Iron and Manganese Iron and Manganese While they commonly occur in high concentrations in groundwater, treatment is easy While they commonly occur in high concentrations in groundwater, treatment is easy

4. Water Pollution Water Pollution occurs when water is rendered less fit for use as a result of human activities Water Pollution occurs when water is rendered less fit for use as a result of human activities Waste generated by human activity enters the water environment. Waste generated by human activity enters the water environment. Human Activities Waste Streams Human Activities Waste Streams -Intensive Irrigation/Agri. -Sewage Waste (Domestic/Indust.) -Intensive Irrigation/Agri. -Sewage Waste (Domestic/Indust.) -Mining activities -Gray water -Mining activities -Gray water -Industrial activity -Stormwater -Industrial activity -Stormwater -Dense human settlements -Solid waste -Dense human settlements -Solid waste

5. Protection of Water Everyone needs to be involved Everyone needs to be involved National Government must provide a framework (policy) and legislation for protecting our water sources National Government must provide a framework (policy) and legislation for protecting our water sources Provincial and local level management measures and actions must be developed for giving effect to the national water quality management framework and legislation Provincial and local level management measures and actions must be developed for giving effect to the national water quality management framework and legislation Business Owners Business Owners Industry Industry Mines Mines Farmers Farmers Interest Groups Interest Groups General Public General Public

6. Water Treatment: Chlorination Water-borne diseases are spread by pathogens (disease- causing micro-organisms – such as bacteria and viruses) in water Water-borne diseases are spread by pathogens (disease- causing micro-organisms – such as bacteria and viruses) in water Pathogenic micro-organisms enter water supplies as result of pollution by human and animal wastes. Pathogenic micro-organisms enter water supplies as result of pollution by human and animal wastes. A lot of bacteria and viruses will remain after the First Barrier and Second Barrier treatment A lot of bacteria and viruses will remain after the First Barrier and Second Barrier treatment The final barrier is disinfection – destruction of the harmful micro-organism – though the use of a chemical agent. The final barrier is disinfection – destruction of the harmful micro-organism – though the use of a chemical agent.

7. Water Treatment: Chlorination Types of possible disinfectants Types of possible disinfectants Chlorine, Ozone, Chlorine Dioxide, Calcium hypochlorite (HTH), Sodium hypochlorite (bleach) and monochloramine Chlorine, Ozone, Chlorine Dioxide, Calcium hypochlorite (HTH), Sodium hypochlorite (bleach) and monochloramine Chlorine is by far the most effective, easy to control, cost effective and used in over 98% of water treatment works worldwide. Chlorine is by far the most effective, easy to control, cost effective and used in over 98% of water treatment works worldwide. Side effects and other issues such formation THM’s have been highlighted – they are all minor and negligible as compared to the benefits of chlorinating water. Eg. Cholera epidemic. Side effects and other issues such formation THM’s have been highlighted – they are all minor and negligible as compared to the benefits of chlorinating water. Eg. Cholera epidemic.

5. Water Treatment: Fluoridation Water fluoridation involves addition of predetermined amounts of a fluoride-containing chemical to the water during a water treatment process in order to increase the fluoride concentration to a specific level. Water fluoridation involves addition of predetermined amounts of a fluoride-containing chemical to the water during a water treatment process in order to increase the fluoride concentration to a specific level. The WRC is currently involved in research to parameters and control that determines safe and effective fluoridation of water The WRC is currently involved in research to parameters and control that determines safe and effective fluoridation of water On the other side of the coin is defluoridation where there is also ongoing research to reduce fluoride from waters with high fluoride concentration, though the use of modified locally occurring On the other side of the coin is defluoridation where there is also ongoing research to reduce fluoride from waters with high fluoride concentration, though the use of modified locally occurring

7. Relevant Research Five main fields of research addressed water quality and related problems Five main fields of research addressed water quality and related problems Over 200 projects have been carried out Over 200 projects have been carried out Over R150 million has been spent Over R150 million has been spent Over 30 patents have been taken Over 30 patents have been taken Over 200 reports, workshops, training session. Over 200 reports, workshops, training session. At least 5 centres of expertise At least 5 centres of expertise Over R40 million invested in on going projects Over R40 million invested in on going projects All major water treatment plants are using one or more processes or technology developed through WRC funding All major water treatment plants are using one or more processes or technology developed through WRC funding

RESEARCH OUTPUTS Sewage sludge guidelines and addendum to promote safe use of sludge for crop production Sewage sludge guidelines and addendum to promote safe use of sludge for crop production Compilation of a guide to assess the magnitude of non- point source pollution Compilation of a guide to assess the magnitude of non- point source pollution With DWAF – Development of methodology to implement Waste Discharge Charges (Polluter pays principle) With DWAF – Development of methodology to implement Waste Discharge Charges (Polluter pays principle) Models to simulate effect of acid mine water on the quality of Witbank Dam Models to simulate effect of acid mine water on the quality of Witbank Dam Design of soil covers for coal discard dumps that exclude oxygen formation of acid mine drainage Design of soil covers for coal discard dumps that exclude oxygen formation of acid mine drainage Use saline mine water to irrigate crops and remove gypsum Use saline mine water to irrigate crops and remove gypsum Reduced cost to neutralize acid mine water using cheaper agents. Reduced cost to neutralize acid mine water using cheaper agents.

RESEARCH OUTPUTS Aerobic Digestion (Low cost sanitation) – Almost all waste water treatment plants in SA use this technology Aerobic Digestion (Low cost sanitation) – Almost all waste water treatment plants in SA use this technology Biosure® Process – Treatment of high sulphate waters (acid mine water) Biosure® Process – Treatment of high sulphate waters (acid mine water) Environmental technology and Integrated waste water beneficiation – treatment of high volume saline waters Environmental technology and Integrated waste water beneficiation – treatment of high volume saline waters Petro Process Petro Process Membrane Technologies Membrane Technologies