If you recollect the good olden days, probably some 20 years back, there used to be a Steel Filter which worked on gravity with Ceramic or Earthen Candles inside them which filtered water for drinking purpose. No water water, no energy dependence thus no significant ecological impact. And yes, people were really healthy drinking the water from these filters.

Fast forward, the Reverse Osmosis innovation of the 70s and 80s which made miniature RO plants for small applications made RO purification technologies move from industries to every household. This coupled with false Television Narratives like ‘Sabse Shuddh Paani’ made people fall into the trap of buying RO purifiers without even thinking about, do we really need it? What are the health consequences, nobody cared for. Apart from that, the RO technicians will set the TDS level to the lowest possible level, which deprives the users from all vital minerals.

On top of it, a typical RO purification system used in households rejects 3 to 3.5 liters of water for every 1 liter of purified water. In a typical 100 flat apartment scenario, this reject water will be over 12000 liters / day or 1 standard tanker load of water. And yes, this is the drinking water which most of them would have purchased from external sources like BWSSB or tankers or extracted from tubewells which costs similar amounts on electricity. Apart from that, this RO discard (or reject as many people call it) will have an impact on down the stream treatment plants & water bodies as well. Per capita water demand of Bengaluru has increased due to increase in the number of such RO purification units.

Is there any solution?
Truly speaking, RO purifiers found a place in the majority of homes in India. This can solely be attributed to a nice marketing strategy by these companies, nothing more than that. Majority of homes do not even need RO Purification. BWSSB supplied piped water is always at less than 200 TDS level, thus not requiring RO purification at all. Also, the multi-storied apartments have WTPs (Water Treatment Plants) commonly installed, which treat water and also reduce hardness.

Apart from that, premier research institutes in India like BARC (Bhabha Atomic Research Center) have developed the filtering membranes which does the purification work without actually discarding any water. BARC membranes can easily be retrofitted in any of the commercially available RO purifiers and these membranes are easily available on Online Marketplaces. Close Loop RO purification units and ceramic based filtration units are available as well. Also, they are almost at the same price levels like traditional RO purifiers.

Technology has evolved, but mindset hasn’t evolved. Also, the false sense of water abundance has made many people ignore the water discarded & wasted from RO purifiers. But yes, the situation which is prevalent in Bengaluru today would be a good time to concentrate on these technologies. And yes, if it takes time to adapt these technologies, reuse of RO discarded water should take the highest priority.

One last line, ‘There is no WASTE water, there is only WASTED water’