THEY knock on your door, these two neatly dressed chaps. Like all well-trained salesmen, they are quick off their marks. “We want to show you something interesting. Just bring us a glass of water,” they say. They then shove in a couple of electrodes and viola, and the water in their glass turns blackish. “See how impure your drinking water is,” they say. “Now, look at how clean a glass of our RO (reverse osmosis)-treated water is,” they say, doing the same test on some water they have brought along. “If you really want to protect your children’s health, why not use our great reverse osmosis filter that is used by Bollywood stars?”

When you point out you have given them a glass of the most popular brand of mineral water, and that brackishness is actually essential salts and minerals, without which water is lifeless and of no value, see how they run away!

“The water purifier market is likely to touch Rs 7,000 crore by 2015 from the current market size of about Rs 3,200 crore,” says Mahesh Gupta, the chairman of an RO outfit that had 40% market share India-wide some 15 months ago.

“The RO con is on, and it is alarming to see how many middle class people are being conned in Bettiah, where the water contains a lot of natural minerals and essential salts,” remarks a friend. Today, being World Water Day, here’s a question: Is your friendly neighbourhood salesman helping to create a drinking water crisis in Patna , which by and large has good potable water?

A paper on ‘Assessment Of Ground Water Quality In Patna, Bihar , India’ by Saba Hasnain, Subodh Narayan and Chandrawati (2008), based on 100 samples of groundwater from 10 selected sites representing all the three zones of Patna (eastern, central and western) were analysed for physicochemical characteristics with special reference to its vital parameters, i.e. Conductivity, pH, Total Hardness, Total Alkalinity , Sulphate, Nitrate, and so on. The results were compared with standard Indian and International norms. The groundwater quality of Patna was found to be well within the national and international norms.

Just three months ago, the Shree Krishna water and nutrient testing laboratory and research centre, popularly known as Shree Krishna Gyan Mandir (SKGM), come out with a ‘startling revelation’ that tap water from Patna railway station platforms is ‘healthier than most of the branded bottled water being sold there’. The test was carried out on as many as 15 parameters and it was found much better in quality than some bottled water brands, said Kodaikanal-based Wash Institute’s chief executive officer Prakash Kumar.

“The problem with RO purifiers is not in the water safety. Reverse Osmosis is used to separate out solid constituents and other dissolved particulates by forcing water under pressure through a micro-sieve. By using this technology, even brackish water can be made drinkable. The catch is in the details,” says blogger Sumanth Suresh.

“For every litre of potable water produced, the RO purifier dumps 3-4 litres of waste water. If you pass 4 litres of water through an RO purifier, it would produce only 1 litre of potable water. Now, this wastage is admissible if one is trying to convert brackish water into drinking water. But the water that is supplied through borewells or tankers or cans is not brackish! They are largely usable, with minimal filtration and UV. Since the RO purifiers are designed for treating even brackish water, they perform poorly in the normal household conditions. For every one litre of water produced, the remaining 3 litres go waste when they could have actually been used for non-drinking applications. This presents a serious concern since the final beneficiary of imposing further water shortages is the RO companies,” he points out.

The bottom line, says Robert Athickal from Taru Mitra-Patna, is that while an expensive RO filter may be useful for places with brackish and highly contaminated water, simpler water filters can do the job just as well and save electricity and wastage.

