The Ministry of Environment and Forests (MoEF) is reluctant to impose a prohibition on Reverse Osmosis (RO) technology use for purifying water.

In May this year, the Supreme Court upheld the National Green Tribunal’s (NGT) order for the prohibiting use of RO in any case where the total dissolved solids (TDS) measure in water is less than 500 mg/liter. TDS are naturally present organic or inorganic substances smaller than two micrometers, including those substances that occur due to natural weathering of rocks and soil, which find their way into water.

Water Quality Association India, which includes stakeholders from RO companies, moved the SC against NGT’s orders. Subsequently, SC asked the RO companies, according to an order issued on November 22, to submit representations to MoEF, before asking the Ministry to issue a notification on prohibition. However, a senior MoEF official told Businessline, “MoEF is not an agency that can ban technology. I can guide about the ill effects of the product but I cannot enforce a ban on your method of purifying water.”

Wastage of drinking water

The bone of contention behind the judicious use of RO technology as has been argued by a non-profit ‘Friends’ in the green court since 2015 is the unnecessary wastage of water, up to 80 per cent, while the water gets purified through methods such as hyper-filtration, in which only concentrated solution of water is available for drinking, while majority of the water content is discarded. For example, according to documents submitted in the SC, reviewed by Businessline, Tata Power Delhi Distribution Company (TPDDC) admitted that huge ROs installed by several institutions contribute to shortage of safe drinking water for people and wastage from such RO systems is 2,32,500 litres per day.

While SC and NGT have asked MoEF to come up with a notification by December 31, the MoEF official said that issuing such a notification may not be possible. “We may work on issuing guidelines to consumers on what happens when water is purified in RO, and whether there is a loss of minerals like calcium and magnesium in the process. But at the same time we are being asked to comply with NGT and SC. We will have to be prudent,” said the official.

NGT will hear the matter, and the progress made, on January 10 next year. The SC in it’s order last week, said that the industry stakeholders including the RO companies are to submit their representations to MoEF by December 2. “Once the representations of the RO companies come in, we will examine them and then accordingly proceed ahead,” MoEF’s Secretary, CK Mishra, told Businessline.

The MoEF official added that under the Environment Protection Act, 1986 the Ministry is responsible to check the quality of effluents and discharge, but not impose any bans. “The Central Pollution Control Board (CPCB) is mandated to ensure that the discharge (including that of RO water) complies with standards set for domestic and industry purposes. If it does not, CPCB takes action,” said the official.

MoEF is reluctant to impose a prohibition on RO, but while providing the expert committee report, of which it was a part, it said, “RO technology is not required for places having piped water supplies from rivers, lakes, ponds where TDS levels far lower than ground water sources. Installation of RO plants is advisable for sources having TDS levels above 500 mg/litre, but for below 500 mg/litre TDS levels, ultrafiltration technology clubbed with ultraviolet radiation suffices.”

NGT based on expert committee recommendations said that the local bodies like municipal corporations shall inform consumers about water source and quality including TDS concentration of water being supplied while generating water bills.

On November 4 in an order, NGT told MoEF that delay in compliance of order is causing harm to public health and environment in terms of expert committee report (to which MoEF is a party). It also warned that failure of the concerned officers to comply with directions of the tribunal can lead to punishment under Section 26 of NGT Act, 2010 also by the way of imprisonment, and that December 31 is the deadline for MoEF to comply else from from January 1, concerned officer in charge will not be entitled to draw salary and further coercive measures may be considered.

“The Ministry is working towards, whose salary will be stopped and whose not is not the question,” said MoEF’s Joint Secretary, Jigmet Takpa, who was asked to remain present during the NGT hearing for fixing of responsibility.

NGT also opined that RO company’s liability needs to be fixed for online digital display of instant TDS concentration of treated water, proper labelling on purifiers specifying that the unit should be used only if TDS is more than 500 mg/litre, geo-tagging for recording disposal of used cartridges, and so on. A MoEF official said, “Yes, these points will also be a part of the stakeholders consultation that we are having and we can expect results to come out on December 31.”

Rahul Choudhary, lawyer for NGO Friends who filed the petition in NGT said, “Application of RO in developed countries is only for desalination (producing drinking water from high TDS sea water or brackish water) and treating low TDS water with RO is a new normal in India. Claimants (RO companies) are promoting it to remove multiple pollutants, but universality of this technology without addressing the limitations would create long term problems rather than short term solutions.”

Unwarranted ban

Meanwhile, industry sources said that any kind of ban on use of RO technology is unwarranted and one of their key arguments has been that even if TDS is within 500gm/l limit, drinking water may still contain other contaminants such as heavy metals, pesticides and micro-plastics.

An industry player added that some residential RO water purifiers already have the ability to achieve 50-60 per cent water recovery, while some commercially-used RO water purifiers have the ability to recover an even higher percentage of water.

Industry sources said that such a ban on the use of RO water purifiers will not just have an adverse impact on the RO water purifier sector but could also have an impact on other industries such as pharmaceuticals and packaged drinking water.

(with inputs from Meenakshi Verma Ambwani)