The cities of modern India, the concrete jungles, are on the brink of severe water crisis. One city is competing with another as to which will dry up first.
A recent National Geophysical Research Institute (NGRI) finding states that the ground water in cities like Hyderabad, Chennai, Delhi and Mumbai along with several other cities of North India is declining at a rapid pace.
The graph accompanying the report shows that most of the cities in the north of India, in a short span of next 3 years would have no ground water beneath.
The report goes on to state,
“History shows that civilizations have vanished once water is gone. Water carries people and we need to do something before it is too late.”
This alarming situation has been primarily created because the cities have become concrete jungles. The channels to the local aquifers through which the rain water seeped in, have all been sealed. They have become places for public utility, thus depriving the land below the cities of their water. Consequently, the ground water that comes up through bore wells has got high levels of chloride and nitrates which in excess are harmful to our health.
What is the way out?
We have to first become alive to the situation, recognize that we have a problem on hand and act constructively before it is too late.
First what is an aquifer?
Underneath the hard rock on the surface of the earth, are layers of different types of rock. Some layers such as sandstone, conglomerate, fractured limestone, unconsolidated sand and gravel, basalt etc. have some amount of porosity and therefore allow water to seep and flow through them. Each type of rock allows the water to flow faster or slower depending on the size of its pores.
Water seeps in and exists within each rocky layer. Depending on the pattern in which these rocky layers are formed in the earth, water chooses to flow faster or slower in certain paths.
Thus if we can see through the rocks, we will see a slowly moving water body. This body of rock through which water is moving, is called an aquifer.
An aquifer should not be mistaken for an underground river. An underground river is one that has a clear cut channel for water to move under the ground. Water does not have to seep through the rocks to move. It flows freely in the channel. It is just that the channel is buried and not seen from above ground.
Since in an aquifer, the water travels through tiny pores of the rocks, the water that comes out of an aquifer is usually clean.
Aquifers have natural recharge zones where water enters the rocky layer and they have a natural discharge zone where the water comes out of the rocks and collects as a pool or well. In between, man can intervene and drill into these rocks and tap into the aquifers. These are the bore wells of today.
It is because of these aquifers and plenty of recharge zones which allowed rain water to seep in, that we had wells, springs and tanks overflowing with water right through the year in India, across all seasons, even in times of failed monsoon.
In present times the situation is quite different.
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Aquifer recharge zones have been blocked with unmindful construction.
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Aquifer discharge zones have also been blocked with unmindful construction.
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Aquifers have been tapped into indiscriminately with powerful bore wells.
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Aquifers are being drained at a rate faster than that at which they are getting recharged.
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Aquifer recharge zones are contaminated with chemicals and bacteria which enter the acquifer.
As a result, aquifers which are the main source of clean, ground water have all dried up and the result is water shortage everywhere.
Much of this is happening in cities since there are more people trying to live off the limited number of aquifers under the city.
When we construct any building, the first thing we need to do is build a foundation which goes to a depth that is calculated in proportion to the height of the building we want to construct.
Then why is it that when we come to cities, we do not make such fundamental calculations to build and populate in a regulated manner?
We think that a building is supported only by the concrete foundation below. We fail to think of the amount of ground water that will be available to support all the inhabitants of the building once it is completed.
Today’s buildings stand much beyond what their foundations can support – not the concrete ones but the rocky aquifers. The height of buildings in cities has far exceeded the depth of the aquifers available. The cities have literally sucked all the water out of the aquifers. To keep life in the cities going, water from aquifers in nearby areas too have been extracted and supplied to the cities.
The red zone in the graph is the most densely populated region of India as well as the world. No wonder we are seeing the graph as published by the NGRI.
Can our aquifers give us water once again?
Let us first look at what our ancestors had followed.
We may laugh at them for revering water as Punya Theertha, holy water. But they were wise enough to build percolation tanks for every small area of inhabitation. Typically these were built near temples and at outskirts of the village alongside slopes to catch the rainwater. These percolation tanks kept the aquifers recharged. The collection of water from these aquifers was also from natural wells, springs etc. which ensure that only as much as the aquifer could discharge was collected. They did not indiscriminately use powerful motors to suck up the waters from the aquifer faster than it could accumulate.
All this also meant that the population of any settlement was automatically regulated so that there was no undue burden on the aquifer and natural water resources.
Z To A
People are usually in the habit of using a phrase “A to Z”. But here we will talk about “Z to A”. Lets see what it means.
We have water harnessing practices which are local to the topography and climate of the region, across the length and breadth of India.
The water harnessing system in Ladakh in the North, is called the Zing, where they collect the waters as the snow melts, and channelize them for their agriculture and residential needs.
Kutch in the west, has its own system called Vradha.
It is Apatani in Arunachal Pradesh in the east.
In South India, it is the Eri, large tanks, Oorani, the smaller ponds and Annaicut, which are the water diversionary bunds.
In this land, through the years, the people have devised their own water harnessing practices from Zing in Ladakh to Annaicut of Kanyakumari, i.e. from Z to A. The people of this land have thereby harnessed the water for their prosperity through the ages.
Uniform observation
The observations of Megasthenes in 320 BCE , by Al Beruni in 1030 BCE and later by Sir Arthur Cotton show that the land as a whole was prosperous across ages because it employed sustainable water harnessing techniques generation after generation, to harness the monsoon waters and use it through the year for the prosperity of the society, of the civilization.
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