Some basics –
Water is probably the single most important substance on the planet to living organisms. The origins of life on Earth appear to have occurred in water and living cells are generally 70 – 90% water.
We all need around 2.5litres of water a day to survive, much of this comes in our food but without at least 1.5litres of drinking water a day the average human will die.
Isn’t there a lot of it?
About 70% of the surface area of the planet is covered in water but of that vast area the amount which is available for human consumption is frighteningly small.
Over 97% is salt water; this isn’t simply salty it contains dozens of trace elements and impurities and of course considerable quantities of biological organisms and human pollution.
Just over 2.5% is fresh water; this is largely locked up in the polar ice caps and glaciers worldwide. The remaining portion is found in underground aquifers and surface water (rivers, shallow ground waters and lakes)
In short of the available fresh water on Earth only 0.01% is accessible for human consumption.
Can it run out?
The total amount of water on Earth is relatively constant but climate change and human practices can severely alter the balance of how and where we can get clean dinking water.
Abstraction or the removal of water from deep underground has already been shown to allow contamination from salt water which can make its way from the sea to replace the fresh water being removed. This can render entire areas unsuitable for wells or artesian extraction.
Taking water from rivers and lakes has lead in some cases to the total destruction of large areas of habitat and wiped out the livelihoods of those living there.
The Aral Sea is an obvious example:
according to Reuters –
“* Fifty years ago, the Aral Sea was the world’s fourth inland sea, after the Caspian Sea, Lake Superior and Lake Victoria. It started shrinking due to Soviet irrigation projects, its surface area declining by more than 50 percent, to 30,000 square km from 67,000 square km, between 1960 and 1996. The sea level dropped by 16 metres, according to the World Bank.
* The sea straddles the former Soviet Central Asian republics of Kazakhstan and Uzbekistan. It split into a large southern Uzbek part and a smaller Kazakh portion in 1990.
* Central Asia, one of the world’s driest regions, has two main rivers, the Syr Darya and the Amu Darya. Both used to feed the Aral Sea. In the 1960s Soviet planners built a network of irrigation canals to divert their waters into cotton fields in Uzbekistan and Turkmenistan, starving the sea of its life blood.
* Mismanagement of land and water resources has caused degradation extending to the entire Aral Sea basin, damaging fish production and causing high salinity and pollution as well as violent sand storms. Fresh water supplies have diminished and human health problems have risen, according to the World Bank.”
Nitrates from fertilizers and raw effluent can also find their way into ground water leading to severe pollution which either needs to be removed at great cost or the systems have to be abandoned.
The current evidence showing the melting of large parts of the world’s frozen stocks of water mean that the fresh water they contain will be lost and become saline.
Excessive wastage of processed drinking water through use for irrigation, poor infrastructure and practices such as washing cars etc.. can rapidly deplete a resource which should be capable of supplying human needs indefinitely.
The key to ensuring the continuing availability of these essential resources is good management.
It is imperative that water is managed in a sustainable manner;
It is certainly better to work smart than work hard;
We can all make a difference and the difference we make is one of personal choice.
If you wish to simply reduce your current water consumption then look at our suggestions for
If you want to exploit new resources and recycle rain or waste water then look at our guides to