How safe is our drinking water?

How safe is our drinking water is a profoundly important yet controversial and difficult topic; whilst chlorine can remove the bugs it also introduces toxic-THMs. What are they?

The only other option is to harvest and store the rain in tanks; or use bottled-water which comes with risks of its own.

Reverse-osmosis has some benefits but then you lose out on important minerals; the big plus is that all plastic particles are also removed. Our strong recommendation is harvesting rainwater.

Fibreglass rainwater tank.

This page was last updated on 2nd April, 2021.

So just how safe is our drinking water?

Chlorination is arguably one of the greatest breakthroughs in public wellness; cholera and typhoid deaths, and other waterborne diseases have virtually been eliminated in the developed-world.

It has another great benefit over other means of disinfecting public drinking-water; there is a residual effect that continues in the reticulation, destroying bacterial pathogens.

Yet still today over three-million young children die every year in the developing world from waterborne bugs where proper reticulation and sanitisation does not exist.

Bacteria in rainwater are not the problem; it's from free-flowing sewerage that finds its way into streams, rivers and eventually dams.

Suburban rainwater tanks like that above should not be assumed safe to drink from. Yet our dogs do without a problem.

There is a new realisation that the friendly bacteria in the gut play an extremely important role in the prevention of non-communicable diseases. Questions are being asked whether this residual influence of chlorine may have a significant antibiotic effect on the microbiome that lives in the gastrointestinal tracts of humans?

Numerous animal studies suggest that, at the level of chlorine used in our water, it is safe to drink; remember the stomach has large amounts of the acid anyway. However, there is still no research to date that evaluates any possible toxic effect of that residual chemical on the normal-flora that inhabits the gut.

Of greater concern though is the effect of chlorine in our water-reticulation on organic material forming toxic trihalomethanes (THMs) that cause bladder tumours and other problems like miscarriages.

You may have read in the media that Cape Town’s water currently has an earthy taste[1]; it is due to high levels of organic material from the Voëlvlei-Dam. Despite assurances from the authorities that it is safe to drink, residents are rightly concerned.

These findings plus the large number of plastic particles found in our drinking-water, create great difficulties for those concerned about their wellness. Are we becoming neurotic, on the verge of what is known as orthorexia?

That is a pathological worry about right-eating and the fluids we consume; a first cousin to better known anorexia.

For me it is just one more reason we are so pleased to have built an underground reservoir which stores the rainwater we have harvested from the roof; that will certainly have some organic-material from the gutters but, in the absence of chlorine, no THMs are formed. We have a happier microbiome and there is the certainty of no plastic being ingested.

There is little or no risk of waterborne bacteria like E.Coli, or even amoeba from faecal material, but it would be safer to boil it if one intends to drink it; we sterilise with a UV-lamp.

Of course since the beginning of time, humans have been drinking the rain. Yet water scarcity in the world is becoming a major factor in political stability; a large new dam in Ethiopia is threatening peace in East Africa.

Non-nutritive sweeteners

Non-nutritive sweeteners are passed unchanged into the urine; they are frequently being found even in boreholes, groundwater and sewerage treatment plants.

Researchers have already shown that toxic-sweeteners are causing urinary bladder tumours and glucose intolerance leading to diabetes.

In addition researchers have now shown that they increase the transfer of antibiotic resistant genes between the bacteria in our gut[2]. Already nearly a million people worldwide die from these bugs for which there is no known treatment, and it is estimated to rise more than 10-times in the next 30 years.

In addition researchers writing in the Journal of the American Heart Association[3] report a greater incidence of stroke, and three-times increased likelihood of getting dementia if you have just one diet soda per day.

Perfluoroalkyl substances (PFAS)

Perfluoroalkyl substances are to be found in almost all municipal and even underground water-supplies. They are noxious chemicals used in the manufacture of a host of fabrics that are commonly used, like carpets, clothing and food wrappers; nonstick cookware, pizza boxes and makeup too. 

They have hormone-like structures and play havoc with many bodily systems affecting our immune wellness, and raised cholesterol and obesity for example.

Harvesting the rain is one important way of reducing our exposure to them; then we have no concerns as to how safe is our drinking water.


When we drink a glass of water from the tap we have little idea of what else is dissolved in it.

Czech scientists have found that levels of meth are really quite high and have been testing how brown trout respond to the levels of drug-addled water found in many of riverine systems. They love it apparently.

Do drugs also find their way into our reticulation? Just how safe is our drinking water?

Warm water

Bacteria flourish in warm water; thus that from above-ground tanks definitely should not be considered safe to drink without sterilisation.

Rainwater storage should remain our focus; cost is a huge factor. Our harvesting model focuses on the nuts and bolts of building an underground reservoir as has been done in the Netherlands for centuries; the Dutch are the acclaimed masters since 60pc of Holland is below sea-level.

Yet hot water in the home is not negotiable for baths and showers. Depending on how hot it gets it may also not be safe to drink.


Our newsletter is entitled "create a cyan zone" at your home, preserving both yourself, your family and friends, and Mother Earth for future generations. We promise not to spam you with daily emails promoting various products. You may get an occasional nudge to buy one of my books!

Here are the back issues.

  • Mill your own flour
  • Bake your own sourdough bread
  • Microplastics from our water
  • Alternative types of water storage
  • Wear your clothes out
  • Comfort foods
  • Create a bee-friendly environment
  • Go to bed slightly hungry
  • Keep bees
  • Blue zone folk are religious
  • Reduce plastic waste
  • Family is important
  • What can go in compost?
  • Grow broad beans for longevity
  • Harvest and store sunshine
  • Blue zone exercise
  • Harvest and store your rainwater
  • Create a cyan zone at your home

How safe is our drinking water?

Our complete reservoir for collecting our drinking water.

How safe is our drinking water is a question we should all be asking.

Many people do not drink any water these days in the Western world and that is part of the vexing question. On the other hand the added sugar and artificial sweeteners are even more dangerous for our well-being than the other toxic chemicals.

  1.  Cape Town's earthy-tasting water is safe to drink, says city.
  2. Nonnutritive sweeteners can promote the dissemination of antibiotic resistance through conjugative gene-transfer. Web:
  3. Artificially Sweetened Beverages and Stroke, Coronary Heart Disease, and All-Cause Mortality. Web:

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56 Groenekloof Rd,

Hilton, KZN

South Africa