About the Author

Pabitra Mukhopadhyay
Civil Engineer (Kolkata)

Pabitra is an Honors graduate in Civil Engineering from Jadavpur University, Kolkata. He has specialized in the field of River Hydraulics working for more than two decades training rivers, protecting banks and beaches and fighting erosion of the river banks/beds. He has worked with Bio-Engineering models involving mangroves using them as tools for cost effective and natural means of anti-erosion technology.His work is mostly concerning the extremely morpho-dynamic Hugly estuary with Bay of Bengal In course of his work, he got exposed to indegenious people of the Sunderban wetlands, who are fighting a losing battle against agressive Industrialization. Pabitra loves to read and write and he is full of crazy ideas. He believes that he has a tryst with the strange river-country south of Bengal.

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Water Paradox: An approach to understand Water Crisis

Published 18th January 2011 - 9 comments - 4447 views -

There was neither the non-existent nor the existent then.

Darkness was in the beginning hidden by darkness. This all was water.

 The Hymn of Creation (X.129) – Rig Veda 1700 BC

 

Water, the most ubiquitous substance on earth, is at the center of all known life. One of the four elements (the rest being Fire, Soil and Air) that the earliest of human intelligence conceived the earth and all creation to be composed of, is considered precious and life giving almost in all cultures yet all societies compete with each other in the abuse and waste of it. Water is a paradox standing on its head trying to attract attention about the contradiction that is humanity.

Deconstruction of Water Paradox

The paradox starts from the fact that water is both abundant and precious in natural environment.  How abundant is water? The total water reserve on earth is 1,387,216,000 Km3 out of total volume of earth which is 1,083,206,246,123 Km3 (1 Km3 is a volume contained in a tank 1 Km long, 1 Km wide and 1 Km deep) and it is a meager 0.13 % of earth’s substance. But 97.3% of the total water reserve on earth is in oceans that cover almost 70% of earth’s surface. Since we live on earth’s surface it is abundant to us.

 

Volume (106 Km3)

% of total

Oceans

1350

97.3

Polar Ice, Glaciers

29

2.1

Aquifers (Fossil water)

8

0.6

Lakes

0.1

0.01

Soil Moisture

0.1

0.01

Atmosphere (water vapor)

0.013

0.001

Rivers

0.002

0.0002

Biosphere

0.001

0.0001

 Table 1 – Reservoirs of Terrestrial Water 

There are two interesting truths hidden in that table. First, considering ocean water to be saline, the total fresh water reserve on earth is a paltry 2.3% of total terrestrial water. Second, if Climate Change melts down the polar ice and glaciers completely and we still survive and land locked water is still not destroyed by salinization, we will be left with 0.6% of all terrestrial water for our use; irrigation, drinking and sanitation or simply for survival.

Water is so abundant yet so precious for us.

Some say it’s a cruel paradox of nature. Some others say it’s a message for us. 2.3% of our heritance is ready to pick, for the rest we need to be patient, diligent and careful till nature’s own engine sucks some of it from oceans, desalinizes it and pours it on us little by little. Some, however, refuse all those subtle philosophical talks and challenge nature to extract more and more of it from the remote places, places arguably forbidden by nature, aquifers and seas. But then we come back to the same old story of over consumption of resources to destroy subtle natural balances. But one interesting observation should not be ignored: Oceans stood against humans’ innate greed on account of its salinity, as did many mangrove ecologies, yet non-human life flourished in wonderful multitude in saline ecologies of oceans and mangroves. Had it been otherwise, earth’s history would have been completely different in 2010 AD.

Next level of deconstruction

It is very difficult to say at what point of time human civilization started its abusive and wasteful exploits of water. But it is easy to realize that it must have started with fair use and utilization observing a sense of reverence and awe. Almost all cultures have a history that either explicitly or implicitly recognize water as a benefactor. The first leap in human evolution came with its agrarian way of life where water remained central. Agriculture led to earliest settlements, villages, cities and states around natural availability of water mostly along coasts and banks of river, which is suggestive of a new bond between humans and one of the nature’s key resources. The earliest known permanent settlement, which can be classified as urban, is Jericho from 8000–7000 B.C., located near springs and other bodies of water. In Egypt there are traces of wells, and in Mesopotamia of stone rainwater channels, from 3000 B.C. From the early Bronze Age city of Mohenjo-Daro, located in modern Pakistan, archaeologists have found hundreds of ancient wells, water pipes and toilets. The first evidence of the purposeful construction of the water supply, bathrooms, toilets and drainage in Europe comes from Bronze Age Minoan (and Mycenaean) Crete in the second millennium B.C.

These are histories of use. Compare these with recent histories of over extraction of ground water from subsoil and aquifers leading to large scale subsidence of land surface and salt water intrusion in the aquifers, pollution of rivers and oceans with chemicals, detergents and trace metals leading to destruction of aquatic and marine life and modifying earth’s absorptive surface in such a grand scale that the basic hydrological cycle of earth is affected dangerously. These are histories of abuse and I hope to write about them in future.

At the root of such wasteful and careless attitude lies the belief that water is abundant, in fact so abundant that it can tolerate any abuse. And this careless, almost wanton interaction with the human’s most precious resource is in deep disregard of a simple natural rule. The distribution of the terrestrial water as given in table 1 is in place on earth with a fair constancy due to a great natural phenomenon called Global Hydrological Cycle, which is a dynamic system of constant interchange and flow of flux between each natural reservoir with the help of Climate engine and each reservoir has its own recharge or replenishment time. See the figure below:

 

 

 

 

 

 

 

 

 

 

 

 

 Pic 1 : Global Hydrological Cycle with Residence time of each reservoir.

The cycle works in the following manner. Sun heats up water in Oceans which forms vapor; vapor goes up, partly loads the atmosphere and partly forms cloud that precipitates over Oceans and land. The part that falls on land fills up lakes, rivers and in part is absorbed by soil while the remaining part flows over the surface as run-off.  The part that is absorbed by soil goes to refill the sub-soil water table and a little also trickles down to replenish the aquifers. A part of absorbed water on land is taken in by plant roots and again transpirated back into atmosphere. This intricate system is in constant dynamics where each reservoir exchanges some flux with the others and over a period of time the give and take balance so that we can put a net volume against each reservoir.

This is now school level knowledge. However, this school level knowledge was not available even 50 years ago. And what is still not widely appreciated about this cycle is that the different forms of water in the hydrosphere are fully replenished during the hydrological cycle, but at very different rates.  The figure above shows the approximate residence times of water in the major reservoirs.  On average, water is renewed in rivers once every 16 days with the water in the atmosphere completely replaced once every 8 days.  Slower rates of replacement occur in large lakes, glaciers, ocean bodies and groundwater, taking from hundreds to thousands of years.  Some of these resources (especially groundwater) are being used by humans at rates that far exceed their renewal times.  This makes water in slowly replenishing revervoirs effectively non-renewable.

In short, we need to take it easy, which we hardly do. We take it at a speed and quantity which is beyond nature’s own capacity of replenishment and maintaining the equilibrium. In a way water in nature is abundant in quantity but precious in availability, the preciousness is due to nature’s own imposed limits.

Water Crisis – an emerging reality upon deconstruction of the paradox

I hope to write on the global and local aspects of constraints and crises that are emerging when we approach local resource sustainability from the global water balance and large-scale human activities on these reserves. If this is a foreword of my future blogs, the possible chapters may be:

  1. Virtual Water – Commodities, Food, international political economies and regional economies.
  2. Blue and Green Water – Interaction between humans and ecosystems from which economic services are ultimately derived.

If allowed, I would attempt to ‘wade’ through water with two sets of posts, Virtual Water and Blue-Green Water.

 

[Source for table and picture: www.chemgapedia.de]

 


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Comments

  • Npong Balikawu Francis on 18th January 2011:

    what a beautiful peiece. i love it more of that bro


  • Kevin Rennie on 19th January 2011:

    Love the mystical hydrology!

    You might like to make a submission to the Queensland Floods Inquiry. Brisbane has a dam that is supposed to collect water during El Niño and stop the river flooding during La Niña. Interesting paradox. Unfortunately our floods tends to follow close on the heels of drought.


  • Kevin Rennie on 19th January 2011:

    Link still working for me. Try this one: Premier launches flood inquiry


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