Toilet: A foot soldier in the fight against climate change

Surprised to see toilets and climate change in the same sentence? I was too, till I visited a public toilet in Dharavi, Asia's biggest slum.

I spent last Saturday visiting a public toilet in Dharavi.

It was part a field trip organised by a group of sustainability and climate practitioners in Mumbai. I wasn’t really sure why this group of people who generally spent their days finding solutions to climate change was going to see a public toilet. But if there is one thing I have learnt so far it is that the causes and solutions to climate change could be anywhere, often in places you least expect. So I went along, prepared to be surprised. And surprised I was!

To begin with, the toilet looked nothing like what I expected!

The facility was clean, hygienic, well lit and well maintained.

So how was this toilet helping solve climate change?

1. A proper toilet connected to a sewage management system avoids contamination of lakes/ rivers and downstream GHG emissions due to untreated waste

In the absence of a proper toilet that is linked to a sewage treatment system, the waste/ sewage ends up directly entering rivers and lakes or seeping into ground water and contaminating it. The wastewater has a high amount of organic matter, nutrients and dissolved organic carbon that reduces the oxygen content in the rivers, and if unchecked can reduce it to such an extent that no life can survive in the river and it becomes a ‘dead river’. It can result in the downstream release of GHG (CO2, methane and nitrous oxide) due to the breakdown of excreta in an uncontrolled environment.

This toilet has a sewage treatment system that enables the waste to be treated properly before it is discharged.

To be clear, there will always be some GHG emissions in waste treatment but in a well designed STP (sewage treatment plant) where the gases are released in a control environment, the GHG emissions can be reduced.

2. Treating wastewater to convert it to grey water that can be reused for flushing/ washing/ landscaping → reducing freshwater demand

The facility has a wastewater treatment system on site that treats the wastewater back into grey water than can be used for flushing, landscaping and washing, thus reducing the freshwater demand by the facility. This is extremely important as most places in India are beginning to see water stress that is likely to only get worse in the future.

3. Solar panels to meet energy requirements for waste water treatment and electricity needs

The facility has solar panels on the rooftop that generates 70% of the total electricity needed - for wastewater treatment, lighting as well as running the washing machines. Waste water treatment needs electricity and thus has some GHG emissions linked to it, as most grid electricity in India is fossil fuel generated. However, the solar panels on the roof enable the facility to use clean energy while also reducing its electricity bill.

Of course, the most important thing the facility does is provide sanitation and dignity to ~50,000 people living in that area. And it’s amazing how it is also such a great lever in the fight against climate change. It’s truly a win-win.

All this is great… but is this financially sustainable?

To my surprise, it is!

The capital cost of setting it up was borne by a public - private partnership. The land was leased by the BMC and the facility was constructed by funds from HUL and some partners. However, the operations of the facility are being completely run by fees collected from users.

The facility charges a fee of INR 150/ month for a family of 5 or INR 3/ use for the toilets and INR 60/ load for the washing machines that are available for use (like a laundromat). The total income it generates from this is sufficient to run the facility (including salaries for staff, utilities and repairs)

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All toilets are not the same

We need to talk about toilets (waste management) a lot more in our conversations on climate. Toilets affect our environment and climate change in 4 major ways:

1. Direct GHG emissions from breakdown of excreta: Municipal waste account for ~1.5% of global GHG (5% of non Co2 GHG) emissions

2. Contamination of freshwater when untreated waste enters rivers, lakes and groundwater

3. Energy required for waste water treatment plants: 3% of total electricity consumption is needed for waste water treatment

4. Water recovery for re-use: Good toilets can help in reducing freshwater demand by enabling the treated water to be used for some activities like flushing, landscaping, cleaning etc.

So.. here’s a little illustration to try and wrap our heads around the role toilets can play in our fight against climate change.

What can you do?

First, try and figure out where your toilet lies on the good/ bad toilet spectrum.

Ask if your residential society has an on-site waste water treatment plant.

If yes, ask what % of the recycled water is finding use.

Ask if you can get solar panels installed that can reduce the grid electricity needed.

Once you know your starting point, try and make it better, one step at a time!

The Suvidha center we visited (public toilets + washing machines + RO water)

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