• Local Authorities in some of the larger towns in Namibia do recycling; NamWater does not do it. 
• There are two different types of large scale recycling used in Namibia. 
• Some towns partially purify their sewerage water and use it for watering public gardens and sports fields.  This water is not intended for human consumption and is delivered in a way that makes it difficult to drink by accident. 
• In Windhoek, sewerage goes through a normal sewerage treatment plant, which makes the water clean enough to use for irrigation, but not for drinking.  The treated sewerage water is then put through another complete treatment process, which cleans the water to an exceptionally high level. 
• The last two parts of the purification process are ultra-filtration and ozonation.  Ultra-filtration pushes the water through a filter in which the holes are so small that water and salt molecules can pass through but bacteria and other small living things cannot pass through. Ultra-filtration effectively disinfects the water, but to make absolutely certain that the water does not contain dangerous organisms, the water is ozonated. 
• Ozone is a gas made from oxygen and will kill any living thing, but the gas only lasts as ozone for a few minutes then turns into the kind of oxygen that we breath, so this is a very powerful short term disinfectant and the ozonated water cannot contain dangerous organisms, it is therefore 100% safe to drink.
• The reclamation process is primarily aimed at making the water clean and safe to drink but does not remove salts that are in the solution.  As water is used and disposed off to the sewerage system it gains some salts, so the water that is produced by the reclamation plant does have a higher salt content than water from the dams that provide water to Windhoek. 
• Water without salt is not healthy to drink and a wide range of salt content is considered acceptable.  The World Health Organisation indicates that water with salt content of up to one thousand parts per million—or one part per thousand—is still suitable for human consumption.  The water from the reclamation plant has much less salt than that. 
• If we try to use 100% recycled water and take the sewerage from this and try to recycle again and again we will soon build up an unacceptable level of salt in the water. A maximum of one third of total supply comes from the reclamation plant and this continuous dilution with water of lower salt content allows the reclamation plant to operate continuously without an unacceptable build up of salts.

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