Blog: Why are cities running out of water?

The City of Cape Town anticipates that its supply of municipal water will run out around March 2018, Mayor Patricia de Lille said last week.

“If consumption is not reduced to the required levels of 500 million litres of collective use per day, we are looking at about March 2018 when the supply of municipal water would not be available,” she said at the unveiling of the city’s critical water shortages disaster plan.

“The day or month of this happening is, however, not as important as what we do now to avoid such a time.”

This begs the question; how are cities running out of water and what can we do to stop this? Clearly Cape Town is an extreme example, and they have high water usage. However, around the world countries suffer periods of poor water supply quite frequently, disrupting people and businesses – or causing ill-health.

A fundamental problem with water supply and demand is due, in part, to our approach to water treatment. In most westernised countries, the standard process is to circulate water around a treatment circuit, investing money and chemicals and energy in it, and treating all the water to potable (or drinking) standard.

That supply is then sent through pipes for every type of water need – be it agriculture, industry, healthcare, farming, flushing toilets or drinking. Around 2% is actually drunk, so there is huge inherent waste in this solution.
At Aqua21 our system of water treatment focusses on treating water at the point of use – and therefore treating it as necessary for its end purpose. Therefore, water could be brought in from any source, local or central, and then made safe at point of use.

Water that isn’t needed wouldn’t be cleaned and therefore wouldn’t be used and wasted. Further to this, water that didn’t need to be drinking standard wouldn’t be given that level of treatment and would only be made safe enough to water plants or clean farm equipment, for instance.

Less water would be wasted using the technology, much more water would be preserved and water systems and supplies could be adaptable to peaks and troughs.

If we are to supply the whole world with clean, safe water, we are going to have to start thinking about water treatment and water supply in a very different way – a 21st way.