- Category: Helgard's Column
- Published on 01 January 2017
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By Helgard Muller
“Leaked report shows ‘catastrophic’ fate facing world: Earth to run out of water by 2050” (www.express.co.uk, dated 19 November 2015).
Such alarmist media reports are quite common. Articles will indicate that “as populations explode” there will not be enough fresh water on our planet. One specific article mentions how groundwater is not being replenished and even published a map obtained from a “secret source” showing where these total dry areas will be in future. This will then enable readers to move away from such barren land before 2050!
These writers conveniently forget a few basic facts. Number one is that the earth contains huge quantities of water in its oceans, lakes, rivers, the atmosphere, and believe it or not, in the rocks of the inner earth. During volcanic eruptions, huge volumes of water are released from the inner crust of the earth. Our planet is also very efficient at keeping this water. Water, as vapour in the earth’s atmosphere, could potentially escape into space from earth. But the water vapour does not get away because certain regions of the atmosphere are extremely cold. For example, when vapour reaches an altitude of 15 kilometres, it’s a staggering minus 60°C — so the vapour simply freezes and falls back to earth.
The number two fact is that water is simply marvellous. Take the freshness of a glass of cold water during a typical heat wave or the smell of the first drops of rain on the parched earth in the Karoo. Water has a rich history — if only the molecules could talk. Have you realised that no water is being created or destroyed on earth? Every drop of water we have in our taps today might have seen the inside of a glacier in the Alps or a cloud in the tropics, or it was part of the moisture in a green ficus leaf or even the inside of a dinosaur’s kidney! Water is constantly recycled time and again — for millions of years. In the very first chapter of his vibrant book, The big thirst, author Charles Fishman summarises it well, “We can use water but never use-up water.” None of the thousands of ways we use water actually consumes the water, including, of course, drinking it ourselves. We just recycle water.
We in South Africa are certainly more aware of water and water problems than people in countries like Canada or Iceland are where water is abundant. But we have been shocked out of our comfort zone by the current drought and the stark reality that even parts of Johannesburg or Pretoria can be without water daily. This leads to fact number three.
Charles Fishman stated — and this is an important fact — “All water problems are local”. A perfect example of this in South Africa is the somewhat theoretical statement we often hear in the news, “Average dam levels are down to X%.” This is really a useless figure: if the biggest dam in South Africa — the Gariep Dam on the Orange River — is 90% full, it cannot help to lift water restrictions in Gauteng or Cape Town. Every town or city is dependent on its local dam levels and water supply system and how well it is maintained and managed. We have all seen this in recent times where dams may have sufficient water, but the systems transporting water are lacking with broken pumps or pipelines out of order.
So the good news is that globally the world cannot run out of water. But reality is — and that is a huge concern — locally in our country or in my city or neighbourhood it remains a daily threat. Something we all need to work hard at to get things right.
• Reference: Fishman, C. (2012) The big thirst. Free Press.