Monday, 12 September 2011

Wanted - water in the right place at the right time

 As the world population grows and the consumption per capita also grows, fresh water is going to be increasingly in demand; not only for drinking but for sanitation and hygiene. Yet droughts in some parts and extreme rainfall in others, or even the two extremes in a given place, are making reliable, clean water supply difficult. Some 900 million people have inadequate access to drinking water while those having bad water-related sanitation or waste disposal number 2.5 billion. According to the World Bank 88% of all waterborne diseases derive from water supplies which are in some way inadequate.

What are the chances of solving this problem? In the long term quite good. It is expected that within a few decades water will become as expensive as oil is today and this means it will become viable to spend money on supplying, conserving and distributing it. But how many have to suffer or die in the mean time? Can we wait for the 'market' to solve this?

 Here are some possibilities:

Lake Baikal in Russia is fed by 365 rivers and contains 20% of the world’s fresh water and there is no reason in principle why this can’t be piped into and around China, where some 2 out of 3 cities are short of water.  Plans for this are being made but as yet there have been no decisions. It could also supply other parts of the world. China is making good progress with wind turbine and solar cell electricity, so the power needed for pumping can be produced without relying on fossil fuels .

Desalination using solar energy could supply water for irrigation and drinking in Africa. The method involves forcing salt water through membranes and this needs energy which can come from solar thermal power generation. A  large European consortium is planning to generate electricity for the European grid using steam driven turbine generators, the steam coming from solar heating plants in North Africa. Siemens, a German engineering company which is part of the consortium, has found a way of reducing by well over 50% the amount of energy needed to turn seawater into drinking water (0.5% salt or less) and has already put this into practice in Singapore.

The monsoon rainfalls are becoming increasingly heavy. It should be possible to conserve the water by diverting it into aquifers and reservoirs for use throughout the year. Political, ethnic, sectarian and religious conflicts are the chief obstacle to the large engineering projects needed. Corruption, poor management and inadequate or non-existent waste disposal  are thought to be the main causes of present water problems, although extreme weather events are not helping, the current floods in South Pakistan being even worse than the those in 2010.

Towing of icebergs, which are made of fresh water, to the coasts of countries where water is in short supply is another possibility which is becoming increasingly viable, although distribution inland will still be a challenge.

Combining these measures with more sparing use of this precious gift CAN solve the problem. In the last analysis it is a question of human will for good or evil.

Author, 2077 AD