A rare commodity
Water is amazing. It is truly the universal solvent. While there are solvents that can dissolve some things far better, there is none that dissolves as many different substances as can water.
It’s all to do with the structure of water’s molecule – that particle scientists refer to when they talk of the tiny bits that some things are made of. Water molecules can cluster together and share parts of each other to form other discrete particles that have unique affinities for different things.
Sugar is made of molecules. Common salt consists of two very different bits, called ions that are positively and negatively charged.
Though sugar and salt look very similar, their fundamental differences, at the sub-microscopic level, make these substances behave so very differently. Very few solvents can dissolve both sugar AND salt for this reason. But water can.
This strange property of water – the ability to dissolve molecular substances as well as those that are made up of ions – is one reason why it is extremely difficult to obtain pure water.
When it rains, droplets of almost 100% pure water form high in the atmosphere. Yet it’s not long before this water has dissolved all sorts of substances, often before it reaches the ground. Pure water is actually an extremely rare substance.
Repositories for everything
Near-pure droplets of rainwater that drench the land eventually find their way into the oceans. There is a little bit of everything to be found in the world’s oceans. This is because water dissolves just about everything.
Gold is one of the world’s rarest and most precious metals. Yet we are told that the world’s oceans contain enough dissolved gold to provide every person with a tiny piece weighing over 8 tonnes!
Gold is just one of the billions of substances that water washes into the world’s oceans, every day. The seas and oceans throughout the world are repositories for all that is washed off the land.
End to fresh water
All over the world, beautiful freshwater lakes represent a half-way house for water that makes its way to the sea. These wonderful reservoirs are topped up by rivers and streams fed by water that takes many paths, from slow percolations of ground water to direct runoffs.
Fresh water reservoirs contain water that has had only a relatively short time in contact with the earth. Most contain water that is near pure. They have enjoyed a place in the eye of the beholder for thousands, perhaps millions of years. Lakes, and the streams and rivers that contribute to them, have served living creatures with necessary fresh water during that time. But this service is literally drying up.
Something in the water
Supplies of drinkable water are dependent on readily available fresh water sources. The demand for water of this purity is increasing every day. I’m told that about 24 litres of fresh water can be used during the entire production of just one hamburger. Yet the world’s fresh water supplies provide water only at a worldly rate.
That rate is huge, and hitherto has been unvarying. While that rate is now not sufficient to provide the world’s demand for fresh water, there is much now happening on the surface of the earth to actually decrease the rate of this provision.
Wastes from farming, industry and the effluent from the people who rely on these present day processes are fast diminishing the usefulness of water sources. Many fresh water reservoirs are now becoming polluted and the level of pollution and the occurrence of this are always increasing.
Now running to ground
About 20% of the world’s fresh water is drawn directly from the ground. It is seen as a way of safeguarding against periods of drought while providing an almost unvarying year-long supply of fresh water – water that slowly percolated its way through the ground. Such water sources are still vulnerable to pollution, however, as surface pollutants can percolate through the ground and contaminate the ground water.
Moreover, the removal of ground water at a rate higher than the natural recharge rate means that these sources diminish in time and can affect water replenishment of nearby reservoirs.
A global contribution
Further to this, some people who support theories of global warming believe that the usage of ground water may actually contribute to global warming, a proposed climatic effect that may also contribute to diminishing the supply of available ground water.
The world’s use of fresh water is now outstripping the rate of its supply. And there are factors brought about through industrialisation and land use that are serving to reduce the suitability of otherwise useable fresh water.
Clearly the world’s populations cannot continue to consume water the way they have been up till now – and it will take more than just a token act of water conservation.