Tap Water Is Not ‘Mineral Water’

RETAIL chains like Pick ‘n Pay, Spar and Fruit and Veg are making a killing by selling water to consumers who do not prefer to drink tap water for various reasons. But the lucrative water business has led to a critical question. What is tap, purified and mineral water? In many shops, the distinction is not clear.

In some shops like Pick ‘n Pay at Wernhil Park in Windhoek, tap water is labelled ‘mineral water’, which is clearly misleading consumers.

This week, The Namibian Consumer asked Maximilian Herzog of Omaruru Beverages, one of the leading bottled water companies in the local market to explain the difference between ‘purified water’ and ‘mineral water.’

Herzog explained that mineral water is distinguished from other types of bottled water by its permanently controlled level and relative proportions of minerals (salts) and trace elements.

“These characteristics determine the taste of the different mineral waters and, more often than not, have one or the other therapeutic (healing) values.

The US Food and Drugs Administration (FDA) as well as the German Mineral and Table Water Act classify mineral water as water containing at least 250 parts per million Total Dissolved Solids (TDS), Herzog said.

“Additionally, mineral water must be sourced from one or more boreholes or springs, originating from a geologically and physically protected underground water source. It must be bottled at source. And most significant, no minerals may be added and the water must be safe to drink in its natural state without any disinfection required. Only if all of the above criteria are met, may the water be distributed as mineral water,” Herzog explained.


In view of this, he said there is nothing protecting consumers in the country when they are misled by retail shops. But he said on its part, Omaruru Beverages does consult the Namibia Standards Institute to ensure that its products meet required standards.

Herzog explained that tap water in cities is often treated with chlorine and is safe to drink as it is controlled by Namwater at the point of distribution.

“However, nobody controls water quality at the point of use-the tap at home.

From point of treatment to point of use, water flows through kilometres of often old and uncleaned pipelines. Furthermore, high chlorine levels and unbalanced mineral contents in tap water lead to unpleasant tastes. Water is incredibly sensitive and probably the most difficult product to bottle or transport through pipelines without accidentally contaminating it,” he said.

He said it is important that the consumer is clearly informed by appropriate labelling and packaging on whether what he intends to buy is mineral water or purified water.


Osmosis water or purified water, often taken from the municipal tap is produced by reverse osmosis or other suitable processes. It may also be called ‘de-mineralised water’ or ‘de-ionised water.’

In comparison to mineral water, Reverse Osmosis Water, after the purifying process, has a near zero Total Dissolved Solids value as practically all minerals have been removed. “It is clearly not a natural product,” said Herzog.

According to Herzog, Reverse Osmosis is a water treatment system that removes most dissolved substances from water by forcing the water through a cellophane-like plastic sheet known as a semi permeable membrane. This process is used for desalination, reclamation of minerals, purification of water, the concentration of whey and treatment of waste water.


“A serious problem associated with the consumption of de-mineralised water is hyper-hydration, also known as ‘water poisoning’. It practically means de-mineralisation of the body by allowing de-mineralised water to draw minerals from the body and wasting them by urination. Hyper-hydration occurs when there is an imbalance of salts and fluids in the human body,” he said.

Herzog said risk of hyper-hydration is especially increased during sporting activities and any activities in hot climates like Namibia when large quantities of salts are lost due to sweating. He said symptoms include dizziness, nausea and vomiting.

“Hyper-hydration can even lead to damage of organs and to death. This is where ‘prepared waters’ kick in by being re-mineralised artificially. Another major problem in operating Reverse Osmosis systems can be the gradual build-up and concentration, at the membrane, of filtered-out substances, and their subsequent fouling. This can cause bacteria to “grow” through the membrane and the water, meant for consumption, to become contaminated,” he said.


Responding on behalf of Pick ‘n Pay, Roux-che Locke, Group Manager for External Relations at the Ohlthaver amp List Group of Companies, said the tank (at Wernhil) is stationed in the back house with pipes running through the roof supplying water in-store.

She said the system has two filters, one permanent that is replaced once every three months by the supplier and the other one cleaned andor replaced every Sunday, when the tank is cleaned.

“We confirm that it is tap water and not from a borehole, but the difference is that this water is further filtered by the system. We apply a number of steps to ensure the purification of the water such as Reverse Osmosis purifiers and pre-filters that are capable and guaranteed of removing over 95% of total dissolved solids, 99% of all organics and 99% of all bacteria,” she said.

Locke said clean bottles are used and filled by staff members to avoid customers having to stand in long queues to get their water.

“Another reason why we clean and replace filters weekly is because Namibia’s water is much ‘harder’ than SA’s, meaning filters’ dirt build-up is faster,” she said.

Source : The Namibian