Engineering: Nature’s Arbiter


By Edwina Ross

Water is a paradox. As the English poet, A.H. Auden, put it, ‘water is the soul of the earth’, yet nature is not known for its restraint or moderation, resulting in the constant need for engineering mediation. While parts of the world suffer drought and subsequent famine, in other parts livelihoods and life are threatened and lost when storms and floods wreak havoc.

We just have to look to ten states across India for a recent example of drought, after two consecutive years of weak monsoons. Presently about 330 million people are affected by severe water shortages. Agriculture, which employs 60% of the population, is suffering terrible crop losses and trains carrying tankers are delivering drinking water to many communities.

India is one of the world’s biggest users of groundwater, drawing more annually than the US and China combined. The water table is already dangerously low and falling on average 0.3 meters (1 foot) a year, but up to 4 meters (13 feet) in some areas. And as farmers drill deeper they are finding the water contaminated by harmful chemicals.

Sorely lacking are India’s surface water storage facilities. The monsoonal rains, thanks to El Niño, are forecast to dump good amounts of water this year. To take advantage of these rains and to amass it for the dry, hot months, their ancient ponds (talabs) and tanks (rapats), many of which have been allowed to deteriorate, should be revived.

There has been some construction, but a myriad more small check dams (naadas or johads) would also help. These obstructions slow the velocity of water, allow it to pool and help restore diminishing aquifers. They also aid in the prevention of erosion and capture silt (further stabilising the damming process). Moreover, the silt and pooling water aids in the growth of vegetation along the water channels.

This link, https://rashidfaridi.com/2013/06/20/time-tasted-ancient-water-harvesting-systems-in-india/ – a description by Rashid Faridi, provides a fascinating insight into water harvesting in India through the ages, and in doing so details the ingenuity of man. Many of these traditional methods remain or have been revitalized and in the face of adversity new ones have been implemented.

These and numerous other engineering schemes to harvest rain are fairly simple and low cost. With a concerted effort to maximise them they could yet relieve the thirsty India of today.

Unfortunately though, alongside expedient, well-intentioned, but flawed government policies these projects often fail to alleviate the extraordinary hardships experienced by many.

For instance, demand for water should be reduced, yet farmers can tap as much groundwater as they like from land they own. And with government incentives, farmers are encouraged to plant crops (even in drought-prone areas), such as rice and sugarcane, which are particularly water-dependent.

Elsewhere over the last couple of months, water has shown itself in a quite different guise. As the northern hemisphere warms for summer and the southern cools, these transitions have seen dreadful flooding in Europe, and on the east coast of Australia; belligerent, damaging storms and torrential, engulfing rain.

The effort to control the fallout from these weather systems is profound and regrettably exacerbated by the folly of man.

Among other flood inducing factors we are deforesting, paving and concreting our earth at an increasing pace; all reducing the ability of the earth to soak up any inundation of water and encouraging dangerous run-off. And we cannot resist building on our beautiful, but mercurial coast lines.

We need water obviously, but we are also drawn to it because of its aesthetic appeal and at times this is at our peril.

The Australian Broadcasting Corporation (ABC) reported on the 6th June: ‘A huge low pressure system that brought flooding and strong winds to New South Wales over the weekend has combined with a king tide to bring widespread coastal destruction, forcing people to flee homes.’
 

With nature doing its best to challenge us it is just as well we have the inventive genius of engineering. As a wise, old woman once said; ‘At its heart, engineering is about using science to find creative, practical solutions. It is a noble profession.’

 

An aside: An interesting fact emerged when I was scanning information on water harvesting in the India of old. I would be most interested to receive feedback from you, either verifying or debunking it:

An ancient Indian custom was to store drinking water in brass vessels to ensure good health. It has been suggested that brass containers help combat many water-borne diseases.
Please send in your argument and evidence. Steve will select a couple of winners, each of whom can select one of our eBooks.


Thanks to the following articles for their invaluable help in writing this:
http://blogs.wsj.com/indiarealtime/2016/04/13/india-delivers-water-by-train-as-drought-in-west-intensifies/
http://www.peasantautonomy.org/himcon-ponds-check-dams.html
http://www.abc.net.au/news/2016-06-06/nsw-homes-evacuated-as-king-tide-combines-with-east-coast-low/7479736
https://www.theguardian.com/world/2016/apr/20/india-drought-affecting-330-million-people-weak-monsoons
http://www.bloomberg.com/news/articles/2016-05-03/india-is-suffering-one-of-its-worst-droughts-in-decades
http://www.bloomberg.com/view/articles/2016-05-01/thirsty-india-needs-to-reduce-its-appetite-for-water
https://www.theguardian.com/environment/2011/jun/08/london-gardens-parks-paved
http://www.nsfarming.com/andrews.htm