The story behind the stink – IISc’s recycled water system

“When the well is dry, we know the worth of water.” – Benjamin Franklin (1746)

While I was once watching an episode of Satyamev Jayate (Amir Khan’s talk show on social initiatives) on poorly managed water resources in the country which was aired back in 2013, my neighbours in Dollars Colony happily let their overhead water tank overflow for more than half an hour. When I went and asked them to stop their pump, they looked at me as if it should be none of my business. Often, the complacence of education is worse than the lack of it. Grudges apart, what can we do to make the best use of what is available to us? As part of the country’s best in research, is the Indian Institute of Science able to lead by example? Well, apparently, yes!

IISc has set-up what can be called the first domestic waste water recycling plant to be established in an educational institute campus in India using state-of-the-art Submerged Membrane Bioreactor (SMBR) technology. Yes, it is the same place whose stink might have bothered you on your way to the new Biological Sciences Building from what-used-to-be-our-beloved Faculty Club Canteen.

The plant has been operational since December, 2010 while the recycled water has been made available through a high-pressure distribution system since October, 2011 which ensures reliable availability of water 24 x 7. At present, it produces more than 5 lakh litres of recycled water per day which is being used for toilet flushing, gardening, car washing, and floor and road washing in different parts of the campus including a few departments, both of the new hostels and the residences. The SMBR technology is able to prevent the presence of all bacteria and most of the common viruses.

Pestered by recurring problems and complaints on water issues in the campus, the institute set up its first Water Committee (WC) comprising of seven professors and the Registrar in 2008. The WC, with the help of hired consultants, completed the rigorous task of preparing a comprehensive Geographical Information System (GIS) of the campus water infrastructure. Apart from setting up the recycling plant, groundwater monitoring was carried out in and around the IISc campus; a water body was created in the Jubilee Garden pond to collect storm run-off for groundwater recharge and a rainwater harvesting initiative was taken up in the new E-type quarters area. The Center for Campus Management and Development (CCMD) had worked with the WC in implementing these measures.

Since IISc buys water from the Bangalore Water Supply and Sewerage Board (BWSSB) at an industry rate of about Rs 70 per kilolitre, the WC thought that it was important to re-use the domestic waste water for non-potable uses. The cost of treated water at the recycling plant, including power supply is about Rs 9 per kilolitre. Although the plant and the distribution system were built with a staggering capital investment of more than 4 crore rupees, the economics of it, as worked out by the WC, promise a payback within approximately four years. In spite of the fact that considerable fractions of the total water consumption in the campus come from groundwater and localized private buying of water from tankers, the total BWSSB water bill of the institute has indeed been reported to come down from the 2012-13 amount by about one crore rupees in the present assessment year.

How useful is the recycled water for the campus? When asked, Prof P. P. Mujumdar, who was the Chairman of the WC when the plant was set-up, answered “almost all the gardening in campus is now being done with recycled water. Some departments also use it for toilet flushing. The setting up of the treatment plant was given to highly reputed multinational companies on a ‘design, build and operate’ contract. Not just that, the entire collection system of domestic waste water was geared up. We understood that just an island of hi-tech is not going to help. We wanted a very high level of service as far as complaints pertaining to water and waste water systems are concerned, which is why a 24 x 7 water helpline was created. The whole idea of an additional source, as far as water availability is concerned, is to build a resilient system.”

On being asked whether any problems were faced in the design, execution and maintenance of the recycled water system, he replied,
“Creating the distribution network for parts of the campus across the bus-route roads was difficult. To SID and the Gymkhana
grounds, pipelines were established over the ground along the pathways. Even inside the main campus, we did not want to dig up the main roads, for which the expensive trenchless technology had to be used. The WC’s aim is to bring out notices prior to expected
shut downs of the plant, though accidental failures are difficult to avoid and do happen. Other than that, there had been some problems like theft of valves from the taps, too”. Now, in a country where lawlessness and corruption have gotten into our bloods, the last one is not a surprise though.

Prof Mujumdar also informed that a similar plant is being planned in the eastern part of the campus behind the Swimming Pool with the intention to create another 5 lakh litres of recycled water per day.

How are the end users reacting to the recycled water system? An ardent lover of nature, Mrs Shubha Bhat, a resident of the E-type quarters, is very happy and satisfied with the supplied recycled water which has helped her rejuvenate the garden beside her house. When I visited her house some months ago, I was pleasantly surprised to find out that she is able to provide shelter to many rare birds! In big pots in her garden, she also rears fish which kill the mosquito larva.

“Earlier, I had to re-use my kitchen waste water and house cleaning water for the plants here, but that was not enough. On the other hand, I was scared to use the potable water that is supplied to the houses for gardening purposes. The recycled water supply has come like a boon to me. Now I can watch beautiful birds take a dip in the water right from my kitchen while I am cooking food. In fact, last winter, migratory birds had also come to the tree beside my house”, she said. “Initially, I was somewhat skeptic about whether they add chemicals into the waste water to treat it, but when I visited the plant, I got to know that it is a membrane that they use. I feel very proud that such a thing has come up in the Institute. Our kids also should see the treatment plant, they should also know about it”, she added.

The Inorganic and Physical Chemistry (IPC) Department also uses the recycled water extensively, not just for the gardening of its lawns, but also for toilet flushing. When I went there to inquire about the benefits or disadvantages of the recycled water system some months ago, Prof. A. G. Samuelson, the then Chairman of IPC had said, “We have been consistently using the recycled water for the last few months for toilet flushing, and for a month before that too, for gardening. Earlier, we were buying tankers at the rate of one to two tankers per week, which means about 10,000 liters on an average, every week. Since the time we have started using the recycled water for the toilets,
we have not bought a single tanker! This is a big improvement for us, because, other than saving water, it is saving us a lot of trouble.
We are very thankful to the administration for making this effort because I think in a sense this was long overdue for a campus of this size. This is a great step!”. Prof. Samuelson had, however, also mentioned that using recycled water for laboratories might entail a little more and the reliability has to be 100% for that.

The IISc Director Prof. Balaram, too seemed positive about this initiative. “The residents are definitely using the recycled water for gardening and car washing”, he said. On being asked whether the recycled water will be further treated to make it suitable for drinking, he jovially replied “I did offer to drink this water. I said, you can then watch me for a week, to see whether I am still coming and going regularly, and at the end of it, take a call”. He emphasized that the water quality parameters are being measured and the water is indeed supposed to be potable. “If you take a scientific view, water is water; and, if every harmful contaminant in it can be measured and quantitated and found to be within the accepted limits for potable water, then it is potable. You see, after all, you do not know what water is supplied in those tankers”, he said.

Why is it then that all the Departments are not using the recycled water? When I had posed this question, Prof. Balram had replied, “This is what the IT-people call the last mile connectivity. Sometimes it is just not there. I think the residents on campus automatically use the water simply because there is a tap there and they can get hold of the water and use it for washing the car or gardening but the
apartments have not taken it with the level of enthusiasm that one might have expected”.

In several laboratories, this treated recycled water can be used; especially in the laboratories where treatments like distillation of water are anyways performed in-situ, there is no reason why recycled water cannot be used. Other than that, recycled water can be used for cooling purposes too. Huge amounts of water can be saved if all the construction works in the campus are carried out with recycled water, given that the amount of constructions, as opposed to the greenery in the Institute, is monotonically increasing. But perhaps, we have yet not realized that the well is dry. One step ahead at a time will take us a long way ahead. The good thing is that a small step has been taken, which will perhaps show the way to others. There are several other campuses and places in Bangalore City where interested people are ready to take up such similar initiatives. Thus, while my neighbour may feel irritated when I ask him to stop wasting water by letting
it overflow, I am sure the next time he does it, he will think twice. And the next time you walk past the recycling plant, you might bear the stink without much ado.

If we humans are responsible for exploiting the earth’s resources with the help of our intelligence to smoothen our lives, I am not ready to believe that we will prove ourselves to be foolish enough to not restore the earth back to a state that is favourable to nature. We must show the way, leading by examples so that our future generations with their paramount intelligence will be able to differentiate between need and greed.

Arpita Mondal