Thursday, 23 July 2015


“And the hooded clouds, like friars, Tell their beads in drops of rain.” - HenryWadsworth Longfellow

How wonderful it is to lie in bed and hear the sound of rain falling on the roof, listen to the gurgling of the water as it runs down the gutters and the sound of cars on the wet streets. One is grateful and the mind turns to places affected by drought, California for example. Australia is often affected by severe droughts and we sympathise with our cousins across the great ditch…

We live on a planet whose surface is largely water, with 71% of it covered by water. However, this water is largely unusable because of its high solute content. Water locked away as ice in the polar regions is fresh, but inaccessible.  Lakes and rivers are becoming increasingly polluted and climate change in many cases reduces their water capacity, with water levels decreasing. Rain falls torrentially in some parts of the world, causing floods and destruction, with little possibility of long-term storage and alarm bells are ringing in many temperate regions where rain is becoming scarcer and scarcer.

Desalination of seawater has been suggested as a possible way of ensuring a reliable, and potentially limitless, fresh water supply for our major urban centres, many of which are coastal. Desalination is already operating in some countries and is providing water, although at a cost! The Middle East Desalination Research Centre, which is located in Muscat (Sultanate of Oman), was conceived out of the Middle East Multilateral Peace Process as an international organisation, which is dedicated to research in desalination technology. As water resources in the region are already under stress and future population and economic growth will require an increased supply, the Centre will seek to bring together scientists, engineers, water policy-makers and water system operators in the Middle East/North Africa region to work on areas of research that will reduce the cost of desalination. The economy of the Middle East is tied to desalination of seawater and brackish ground water.

Another way that can be used to generate fresh water is based on the principle of condensing water from humid air. This technology is already in use in small scale and machines are available for use in the home to produce drinking water directly from the air. To scale up this process is another suggestion for resolving our fresh water supply problems. Cost-effectiveness is the real limiting factor in this process and unless one has access to a cheap, renewable supply of energy, the process becomes too expensive in order to be scaled up. The use of nuclear power to run desalination and condensation plants has various attendant difficulties and raises a host of concerns.

Other ways of ensuring reliable fresh water supplies for big urban centres have been proposed, including increasing use of recycled water from waste water, building larger reservoirs in water catchment areas, better utilisation of groundwater and aquifers and also building urban water supplies that are more water efficient and allow recycling of grey water in applications that would allow its safe use (flushing toilets, watering parks and gardens, some industrial uses).

In any case, increasing public awareness of climate change, water shortages, green-efficient solutions, recycling and cognisance of the importance of reducing waste will help in more effective use of our precious resources.

My word for this Thursday is a neologism that describes what will become an increasingly major issue around the world:
Hydroeconomics |ˈhīdrōˌekəˈnämiks| (noun, pl.)

The study of the physical, cultural, political, and financial aspects of human interaction with the water cycle. The study of hydroeconomics will attract more interest in the near future as human populations find it necessary to make more efficient use of our dwindling fresh water supplies.

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