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| THE CHAMBERS OF
DIRT: Sewage is collected, transported, and assembled, to be
cleaned and then flown back to the river. But in reality, what
goes back is far from clean... |
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Failure of the
flush ‘funda’
First lets see how standard toilets and sewage systems—that all of us
who live in urban India have learnt to take for granted—dispose human
waste.
On paper, this is how it works: When we flush, large amounts of clean
water, physically push excreta and dilute urine down the toilet. Black
water (waste water that carries human sewage) is then mixed with grey
water (from baths, kitchens and sinks), and flown out of the house,
through a pipe. This pipe then joins pipes of other buildings, and
empties itself into the municipal sewer. This sewer, finally joins the
main large trunk sewer. More water is added to prevent the sewer lines
from getting blocked. These trunk sewers then carry the wastes to the
sewage treatment plants (STP). This involves removing the solids as
sludge, getting rid of organic and inorganic pollutants and pathogens.
And finally, the treated water is released in the nearest river or sea.
But like I said…this is all on paper. In reality, the process is not so
smooth and sanitised. First of all, the system is horribly water
wasteful. With each flush, over 10 litres of clean water goes down the
drain.Then more and more of this precious resource is used to simply
flow faeces and urine further and further away from our toilets. Let me
give an example. A family of five contaminates more than 150 thousand
litres of water to transport 250 litres of sewage!!
There is more bad news. Only a small percentage of Indian towns and
cities actually have sewage treatment plants. According to the Central
Pollution Control Board, less than three per cent of the sewage
generated in urban India is treated before the waste water flows back
into the sea or the river.
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TOILET TYPES: Rudimentary structures like these can be
found in some villages of Tamil Nadu |
Even in big cities and metros which
have treatment plants, the capacity of these plants always remain miles
behind the volume of sewage being generated. The government keeps
allocating money to set up more of these hugely expensive STPs—but it
can never keep up with the rate of population growth!
Then, of course, there is the problem of leaky, decaying sewer lines,
which cost an earth to be repaired and maintained. Most municipalities
are cash strapped. So the sewers remain leaky and decaying. Result? A
large amount of the sewage never reaches the STPs!
So, where do these huge mounds of
untreated human filth, loaded with dangerous pathogens go? Into the
rivers, ponds, lakes of course, which incidentally are also the
drinking water source for these cities!!
Destination: Green toilets
Flush toilets and sewerage systems are supposed ensure ‘safe disposal of
human waste matter’. All they are doing now is transferring the problem
elsewhere. They are pushing the harmful pathogens away from homes to the
public at large.
All this makes this system of waste disposal terribly, back breakingly
expensive. Just consider its economic, environmental and public health
costs….
The
Ecosan way
In 1995, Paul Calvert, a Kerala-based ecological sanitation
expert, built a toilet that works in water scarce areas. He
built it in a coastal village in Kerala in which 50 per cent of
families were consuming water that was contaminated by open-air
defecation and 80 per cent of the village had no latrines!
The toilet consists of a slab with a hole over each of the two
vaults it is built on for the faeces to drop in. A funnel-like
device is attached to collect urine, which drains into a plant
bed along with anal cleaning water.
The two holes are used on a rotational basis for six months and
the not-in-use hole is covered with straw to facilitate
decomposition. After each use, some ash is sprinkled down the
holes to facilitate the drying process. The decomposed faeces is
used as soil conditioner! |
Clearly, our sanitation sector needs
a breath of fresh air. All of us need to think beyond flushes.
And, while doing that we need to keep three basic truths in our minds:
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Water is too precious
to be wasted in pushing out faeces;
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We need to manage
excreta as close to where it is generated as possible—because
transporting it across cities is just not viable—economically or
ecologically;
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Faeces and urine are
actually valuable resources and not wastes. Urine can be directly
used as fertiliser and faeces as soil conditioners. In fact, by
ignoring this basic fact, modern sewer systems completely destroy
nature’s nutrient cycle—in which nutrients collected from the land
should be returned to the land. Is it possible to find an
environmentally sound, cheap, and yet modern alternative? Yes it is.
First, we need to look
around. A lot is happening elsewhere in the world. Scientists and
ecologists are developing new concepts of sewer-less cities, using new
technologies which use very little water or no water at all. Some of
these systems have been tried and tested in India as well (see box: The
Ecosan way).
And finally, we need to look within. We may find the answer in
our very own India, with its fascinating diversity of cultures!
The Monpa magic
Not convinced? Then let me tell you the story of the Monpa tribals. They
live in Tawang valley, one of the remotest areas in Arunachal Pradesh, —
located very close to the Tibet border.The Monpas, disciples of Lord
Buddha, are very different from the other tribals found in Arunachal.
They use water wheels to grind grains, which are also supposed to purify
drinking water. The overflow from the wheels are channelised to the
field for irrigation.
The Monpas have developied one of the most sophisticated and
eco-friendly toilet and excreta disposal systems in the world.
About doing or dying
More than 70 years ago, the
farsighted Gandhi—disgusted by seeing people relieving
themselves on river banks—had furiously spoken of the “economic
waste” of the precious manure (excreta), which they would be, if
they were deposited in a field and buried
in the living surface of the earth, instead of being filth in
water and a danger to the health of citizens!
Since then, we have spent crores of rupees in sanitation
engineering. But the Mahatma would still be cringing in disgust,
if he was here to witness what we have achieved out of that!
We need to act really fast to undo what we have done. Or simply
drown in our own waste…. The choice is yours, mine and ours. |
The toilets are built on
bamboo stilts in the backyard. The valley has acres and acres of oak
forests, The oak leaves are stacked in parmong (local name for oak
forests) sheds next to the toilets, and are thrown in, after use. This
is allowed to rot and compost. The entire compost thus formed is turned
over once in a year, stacked up and dried in the fields. This is later
mixed with soil during sowing and transplantation.
In many Monpa houses pigs are kept in the enclosures built underneath
the toilet floor.
Isn’t this an amazing example of sustainable sewage disposal and
recycling system?
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