Tuesday, May 26, 2020

Paradigm in water conservation.


I have been working in the area of Rainwater harvesting for the last 15 years. Though most of my work involves augmenting water supply, I have been also involved in water conservation and demand side management projects as well.

Since I am involved in decentralized projects in housing colonies, factories etc, the design consideration is generally “LPCD” or “Liters per capita per day”. Most projects in housing complexes are designed with the demand pegged at 135 LPCD (though in most urban cases usage is little higher)

Now, if one looks at the number ‘135’, it is the water required per person per day. This is also a legal right of every citizen in India. The breakup of this 135 is given below;

  
USE
LITERS/PERSON/DAY
Drinking
3.00
Cooking
4.00
Bathing
20.00
Flushing
40.00
Washing-clothes
25.00
Washing Utensils
20.00
Gardening
23.00
Total
135.00


The table above is the water requirement per person per day for a hygienic decent living. It is not in the scope of this article whether this is achieved in India or if these numbers are justified.
For the purpose of analysis let us assume that this number is justified.

However, this 135 LPCD is not the amount of water consumed by a person every day. This is just the “direct” demand or consumption by a person. In other words, this is the water that a person consumes from his or her tap directly every day.

The “water footprint” of an individual is much higher that 135 LPCD. We all consume a lot of water indirectly. Our net water footprint is the sum of our direct consumption and indirect consumption.

The food we eat, our clothing, transportation, electricity, consumables, paper, travel, fuel etc have substantial water footprint. This water footprint is rather very difficult to measure or quantify.

In this article I have tried to determine broadly what is the net water endowment available per capita in India. This is an attempt to indirectly determine our water footprint. The below calculations are however broad and general with many assumptions.

The other motivation for this article is to drive home a point on equitable and sustainable water use and distribution.
At a slightly larger picture, we have the following numbers /Data available for India
  •  India’s annual Rainfall + Snowfall run off  = 1600 Billion cubic meters
  • Assuming 50% reaches the seas, we have the net run off of 800 billion cubic meters. That is 800,000 billion liters.
  •  In other words, the annual water endowment to India is 800,000,000,000,000 Liters
  • Population of India is 130,000,00,00.00
  •  Annual water endowment per person = 800,000,000,000,000/130,0000000 = 6,15,384.00 Liters
  • Say 6,15,000 liters is the annual endowment of water per person in India
  • This translates to 6,15,000/365 = 1,684.00 liters per person per day. (Think about it, density of water is 1000 kg/m3. Each individual consuming 1600 liters of water a day is equivalent to energy of 1600 Kgs. That is 1.6 Tons equivalent. So, an individual of 80 Kgs consumes an energy equivalent of 1.6 Tons that is 20 times his weight every day. A tiger weighing 350 kgs consumes a deer of 40 kgs for 3 days. There is no indirect consumption in the animal kingdom)
  • With 135 LPCD being the direct component, the indirect component of the water footprint is 1,684-135 = 1,549 LPCD say 1,500 LPCD.
  • In summary, our water footprint looks like
  •     Ø  Direct component (Domestic consumption): 135 LPCD or 8%
  •     Ø  Indirect component: 1549 LPCD or 92%
  •  As discussed, this 1500 liters is a combination of water used for food, fuel, consumables, paper etc.

NOTE: I have not addressed the question of equity here. We are only discussing the net endowment.

The reason I did this calculation is to drive home the point that we have to look at the larger picture about water conservation than merely looking at taking bath in half a bucket of water or switching off the tap while brushing though these are very much required.

All steps taken at the domestic level to conserve water only reduces the direct demand. Say with best efforts, we may be able to bring our domestic demand from 135 to 100 LPCD. In the larger scheme of things, it translates to about 2% which is also quite significant.

However, we have to look beyond domestic demand and supply calculations for an effective paradigm in sustainable and equitable water distribution.  

Addressing the indirect component of water footprint, we can significantly reduce water consumption and also augment the direct component if required (for health and hygiene reasons).

Hence the point I am trying to make here are;
  • Mere reduction in consumption of goods and services can bring down water footprint significantly.
  • Larger impetus must be given on sustainable agriculture (For example No sugarcane in arid and semi-arid regions).
  • Import substitution of certain goods can save plenty of water. (Water footprint in logistics)
  • Skipping a meal once a week is a good way to conserve water.
  • Going vegan twice a month and fasting twice a month is significant water savings.
  •  Reduce meat consumption or if possible, stop.
  • Locally grown food consumes far lesser water. (With my experiments in rooftop garden, we are able to pluck out vegetables for a family of 3 every alternate day at a water footprint of 50 liters a day that is 16 LPCD.
  •  Rooftop solar is a good way to reduce water footprint. Thermal power plants are water guzzlers.
  • One flight less per year is perhaps equivalent to reducing domestic water footprint from 135.0 to 125.0 per day if not more.
  •  Reducing leather is another great way to reduce water footprint.


The list can go on. But the point is we have to give more impetus on reducing consumption and switch to sustainable consumption.

Education and practicing water conservation measures at home or office is good and is required but we must also look broader and deeper into water footprint and also focus on structural and fundamental changes to become more sustainable, equitable and self-sufficient is water resource.

Sustainability and Equity:

Now an important question arises on why we must reduce direct or indirect consumption. India’s endowment in terms of rainfall is more or less fixed and it is more or less consistent at 1600 billion cubic meters per year. It is a replenishable resource and does come every year, like it or no.

My remarks on this are below;

1.   Though our endowment is by and large consistent , our population is growing. We will need to feed more mouths with less water. Rainfall was 1600 Billion cum in 1930 when population of india (Undivided India) was 40 crore. In 2020 we have about 135 crore people in India with the same available water.
2. Here comes the question of equity. Unfortunately, in India this legal right of 135 LPCD is neither achieved nor measured. Even in urban areas we do not have supply of 135 LPCD.
3.  With increasing temperatures there is a need to enhance the direct demand from 135 to may be 200 LPCD.
4.   Though there is no real data on consumption in India, one can be very certain that there is a huge disparity in consumption. In urban places, I am sure our water footprint is about 4000 LPCD. To reduce this gap and to be more equitable, reduction in consumption is inevitable.
5. Most importantly, though there is a water endowment , it is not available when we need it . It becomes imperative to conserve the precious resource for the time of need.

The term The term 'Conspicuous consumption' was first coined by American economist Thorstein Veblen in the late 19th century. The term has changed its meaning over the last 120 years to very ugly levels.

Given what the world is going through, it is high time that “Sustainable consumption” makes its way into economies and economic theories for a better and cleaner world.  


Next time you visit the amazon website remember the time has come to shift from from 'Conspicuous consumption' to 'conscious consumption',









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