The Central Pollution Control Board (CPCB) has relaxed standards for upcoming sewage treatment plants (STP), including those to come up on extremely polluted stretches of the Ganga.
One of the prongs of the government’s ₹20,000 crore push to clean the river was a 2015-proposal to have higher standards for STPs. That is, they would have to ensure that the biochemical oxygen demand (Bod) — a marker for organic pollutants — in the treated water had to be no more than 10 mg/litre. Existing laws permit BoD up to 30 mg/litre.
However, a notification by the Union Environment Ministry this month has junked the 10 mg/litre target.
It says that STPs coming up after June 2019 — except in major State capitals and metropolitan cities — need only conform to 30 mg/litre of BoD.
These include proposed STPS to treat sewage in stretches of the river downstream of Haridwar, including Kanpur and Allahabad in Uttar Pradesh. New STPs in State capitals, however, have to cap BoD at 20 mg/litre.
Plants in Arunachal Pradesh, Assam, Manipur, Meghalaya, Mizoram, Nagaland, Tripura, Sikkim, Himachal Pradesh, Uttarakhand, Jammu and Kashmir, Andaman and Nicobar islands, Daman & Diu, Lakshwadeep and Dadra and Nagar Haveli, also don’t need to stick to higher sewage-treatment criteria.
Impractical
A senior CPCB official said that the 10 mg criteria was impractical and required advanced technology that was too costly for most States. “We are very far from being able to achieve that kind of quality and we can only go about it in a phased manner,” said Dipankar Saha, of the (CPCB), who was involved in crafting the standards.
“It’s a step forward, because now we also have standards for faecal coliform, which has never been part of our standards,” Mr. Saha said.
