The Union Environment Ministry has published a draft notification that effectively prohibits users from installing membrane-based water purification, mainly reverse osmosis, systems in their homes if the water has been sourced from a supply that meets the Bureau of Indian Standards’ drinking water norms.
“Installation or use of MWPS [Membrane based Water Purification System] shall be prohibited, at the point of use or at the point of entry for purification of supplied water which is subjected to conventional flocculation, filtration and disinfection process or is from any sources which are in compliance with acceptable limit for drinking water prescribed by Bureau of Indian Standard 10500:2012,” the Ministry said in the notification, made public on Monday. The proposed regulation is not the final word and the Ministry will await comments from the public for 30 days, after which it may incorporate the changes before it becomes a law.
The Delhi Jal Board, among others, claims that the water it supplies meets BIS norms.
The Ministry has issued this order to comply with an order of the National Green Tribunal, which has prohibited the use of reverse osmosis (RO) purifiers in places where total dissolved solids (TDS) in the supplied water are below 500 mg per litre.
The Water Quality Association of India, which represents companies that make RO systems, had moved the Supreme Court for a stay of the NGT’s order. The SC declined to intervene and the NGT had directed the Environment Ministry to issue a notification that restricted the use of water filters. The NGT had ordered a ban on RO filters on the grounds that they wasted water and that, in the process of removing salts, they often deprived drinking water of essential salts. RO while useful in reducing salts does not tackle bacterial agents or trace chemicals and manufacturers often claim that additional filtration is required to deliver potable water.
“This is a work in progress... users will not be prosecuted for installing RO systems,” Jigmet Takpa, Joint Secretary, Union Environment Ministry, told The Hindu . “However, this is part of a significant change we are implementing to regulate RO manufacturers and inform consumers that RO systems aren’t needed always,” he added.
Current BIS regulations consider 500 mg/litre—1,200 mg/l of total dissolved solids, which consists of salts and some organic matter, as acceptable though there is no lower limit.
The regulations also put the onus on commercial bottlers, who make RO water, to ensure that water that is lost in the RO production process is stored in “safe, hygienic” conditions and that a record of such water “wasted” is maintained. Makers of such systems have to register with the Central Pollution Control Board. By June 5, 2022, RO manufacturers can only supply home purification systems that waste no more than 25% of the water and these systems must be able to inform consumers of the TDS levels at the inlet and water outlet, the Ministry adds.
