Question : Usage of RO WaterPurifiers

(a) whether RO water purifier systems have been installed in houses located in several urban areas of the country;

(b) if so, the amount of water in percentage estimated to get wasted during water purification in RO system specially in for metropolitian cities;

(c) the percentage of loss of calcium and other nutrients present in water during the said process; and

(d) whether the Government has received any proposal for looking into the loss of water and nutrients during the said purpose; and if so, the reaction of the Government thereto?

(a) Yes, sir.

(b) The reject generated from Reverse Osmosis (RO) system depends on the quality of feed water and permeate. The reject quantity varies between 1 to 3 litre per litre of permeate depending on the size and purpose of RO system.

(c) No such study has been carried out by the Ministry.

(d) In the matter of OA No.134 of 2015 titled ‘Friends through its General Secretary versus Ministry of Water Resources’, Hon’ble National Green Tribunal,vide its order dated 20.5.2019, has instructed the Ministry of Environment, Forest and Climate Change to issue appropriate notification prohibiting the use of drinking water prepared through RO systems where the amount of Total Dissolved Solids (TDS) is less than 500 milligram per litre and wherever RO is permitted, a requirement be laid down for recovery of water be more than 60 per cent. In pursuance of above order, Ministry of Environment, Forest and Climate Change has published draft notification for regulation of Membrane Based Water Purification System.

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