In the summer of 2013, we ran out of water in our home in Madurai. Like many others, we depend on the water that our borewell supplies, but after drilling past 500 feet, we hit a slushy bottom – our borewell’s way of telling us to look elsewhere. An electrician familiar with the workings of our house for decades said the house had never run out of water, which made us inclined to believe this water outage was a passing problem and more to do with the working of the borewell. My emails from this period reflect our concern with the functioning of the borewell and the muddiness of the column rather than with any fear of the aquifer drying up. Like many, we believed that the supply of underground water was endless.
How mistaken we were. In a year, we were spending thousands of rupees to buy water. By that time, I had personally gone from a climate-change ignoramus to knowing enough to fear that something may seriously be amiss. We are fortunate in having a large garden, but only after buying water did we understand just how much water it took to maintain – paying a meaningful price for water had forced us to look closely at our demand. That’s when we realized we did not know how we were using our water or, indeed, how much we were using. We had a vague suspicion that the garden and the bathrooms were the biggest culprits and perhaps the RO unit might be wasting too much water. So, we began monitoring RO use and how often the garden was watered. We tested and found that the raw water from the borewell needed filtration, as the TDS levels were too high for domestic use, but we also discovered that the RO unit was rejecting a lot of perfectly good water.
With a very young baby in the house, we were not open at the time to experimenting with drinking water quality. Instead, in 2014, we captured the water rejected by the RO unit in a tank, and after ensuring the TDS level was acceptable, we began using this in the garden. At first, our water consumption did not go down. It was only later, in 2015, when we fitted water meters around the house that we found the reject water wasn’t reused, it was just being tossed into the drain. The meter readings proved invaluable in other ways as well. Within a month of readings, we realized we were losing a lot of water when the overhead tank overflowed. We fixed a float valve: now, whenever the level of water rose to a preset level in the tank, the borewell motor would be automatically shut off. In the kitchen, which came up as a water guzzler, we took a leaf from South Africa’s water-saving journey and reduced the pressure of the water in the taps. This lowered the amount of water used in the kitchen without the need to be constantly watchful.
Finally, we lowered the amount of water rejected by our RO unit, despite the technician telling us that membrane life would be affected. Here, I must admit, I relied on the advice of an engineer at a desalination plant in Israel, who said that given our input water quality, reducing the amount of water rejected was a no-brainer. The membrane’s life has not fallen. We then fitted a meter on the reject water tank, which helped us track and ensure that the garden was watered with reject rather than raw water. This reuse was a game changer in bringing down our freshwater consumption. My neighbour – who transports and uses higher-quality water for his garden – warned us that our plants may die with reject water. We do test our input and reject water regularly to both decide how much water to reject and ensure the reject water is safe to reuse. Despite the use of reject water, if you were to visit our home, you will see a lush almost-jungle in the backyard.
Within a few months, we stopped buying water, but continued to innovate. Over time, my understanding of our water has improved, and I have realized that our relationship with our water is a journey. Like any journey, there have been some bumps on the road. I opted for a new type of water-saving water closet, which, though it was a reputed brand, failed to work in the most embarrassing fashion, with a ‘will-it-won’t-it’ flushing anxiety, which is undesirable. We now keep a bucket handy to help with flushing.
On the other hand, we have our victories as well. We renewed and added to our very old rainwater-harvesting (RWH) system. Whenever it rained heavily, we noticed that the rainwater – our rainwater – was escaping into the street. We dug a ditch, with a grill above it, before the gate, to channel the rainwater into a harvesting pit rather than let it flow into the street. We use compost and mulch extensively in the garden, so any rain falling there is sucked into and stored in the soil. We send no part of our food waste or garden waste out of the house; all of it becomes compost (or biogas). Compost is really black gold as it changes soil structure to make soil more water-friendly, even while helping plants thrive. We relish the succulent tomatoes and spinach that the garden – run on reject water and compost – provides.
Excerpted with permission of Hachette India from Watershed: How We Destroyed India’s Water and How We Can Save It by Mridula Ramesh. Hardback I 432pp I Rs. 699