‘The study should be repeated’: Central Pollution Control Board, experts question accuracy of BIS water study

A study by the Bureau of Indian Standards that tested the quality of piped drinking water across the country stirred controversy when it rated Delhi as having some of the poorest quality tapwater out of 21 cities, alongside Kolkata and Chennai. 

However, the study has raised more questions than it answers. 

BIS is responsible for the “standardization, marking and quality certification of goods”. Yet, the Central Pollution Control Board, which spearheads water quality standards, has suggested that BIS’s study be “repeated”. It also pointed to the fact that only 11 samples were taken for a city of Delhi’s size.

The 11 samples included households in 12 Janpath, Karawal Nagar, Ashok Nagar and Janta Vihar. The study said the samples “non-conformed” to some parameters. The parameters include colour, odour, pH, total dissolved solids, hardness, alkalinity, elemental compounds such as iron, manganese, sulphate, nitrate, chloride, fluoride, arsenic, chromium, copper, cyanide, lead, mercury, zinc and coliform bacteria.

These results led to a war of words between Consumer Affairs Minister Ram Vilas Paswan and Delhi Chief Minister Arvind Kejriwal. While Paswan “challenged” Kejriwal to name officials for a team to test the water in the capital, Kejriwal accused him of “spreading lies and misleading people”. Manoj Tiwari, BJP MP from Northeast Delhi, jumped into the fray and said the study results have led to “uncontrolled panic” in Delhi.

The AAP has now said it will form 32 teams to collect drinking water samples from across the city.

Newslaundry examined an elaborate 2016 study on water quality carried out by the Central Pollution Control Board, based on orders from the National Green Tribunal. The 2016 study collected 86 samples from households across nine zones in Delhi — in comparison to the BIS’s use of only 11 samples — and measured the water quality against prescribed BIS standards. 

Interestingly, the findings of the CPCB study are not alarming. Out of 86 samples, only six had water quality that failed permissible allowances of BIS standards. 

Newslaundry reached out to AK Sinha, retired additional director of CPCB and the person who headed the 2016 study. When asked what methodology the study used, he said, “The samples were taken from all the reservoirs, water treatment plants and all the zones across Delhi. We did it with the Delhi Jal Board which is in charge of monitoring the water quality in the city. The quality of the water was measured against the standards set by BIS.” 

This points to another aspect of the BIS study: it did not take the help of the Delhi Jal Board. If anything, the Jal Board seems clueless that the study happened in the first place. DJB was clueless of this study taking place. “We were not only informed about the study,” said Dinesh Mohaniya, vice-chairman of the Jal Board. “The 11 locations were not disclosed even after us asking them to give us details.”

In May, the Jal Board had told the National Green Tribunal that the water it supplies in the capital is “fit enough” to drink straight from the tap. So, a short five months later, how is the BIS study in such stark contrast?

Sinha said he “doesn’t know how the BIS got their study done in just 11 samples”. He suggested the study be repeated. 

“We used to check the water and air and a lot of environment-related issues across the country,” he explained. “But it never came out that Delhi water is the worst. It was as bad or good as it would be in any other city. Of course, a few areas like Maharanibagh in east Delhi had people defecating into the river. But the overall water quality was not toxic.”

He added that with just 11 samples, it’s difficult to come to a conclusion on the water quality in Delhi. “Delhi is huge. There are so many zones — every zone should be covered and only then one would know about the water quality. I don’t know how they got their study done in just 11 samples.” 

On November 19, Paswan tweeted a list of the 11 households from where samples were collected. Yesterday, NDTV published a ground report, visiting the households where the BIS’s samples were obtained, and interviewing residents on water quality. Surprisingly, most people denied having issues with the water, or even giving samples in the first place. 

Meanwhile, the Delhi Jal Board is independently checking the water quality of the 11 samples cited in the BIS study. “We are not only checking the sample which they took, we are additionally checking around 3,000 samples across Delhi,” vice-chairman Dinesh Mohaniya said. 

A Sudhakar, the divisional head of the water quality monitoring division at CPCB, said the consumer affairs ministry might want to bring in a mandatory rule for water quality. “All these standards are still voluntary and people can follow or not follow it,” he pointed out. “I think the ministry wants a mandatory standard and for that, this study was conducted.” 

Sudhakar admitted he “doesn’t know why” BIS conducted this study. “Like every commodity, water also is checked on a regular basis before being supplied to people. The Delhi Jal Board has a water quality monitoring system in place. This is BIS’s first study and usually, it just sets standards.”

Mohaniya agreed. “The water quality in 500 locations is checked on a regular basis in Delhi. We didn’t find anything this alarming till date.”

Rahul Choudhary, an environmental lawyer, said the BIS has, in the past, merely emphasised its position as a standardisation authority. “Whenever any queries were raised in the National Green Tribunal over a certain commodity not meeting standards, the BIS would reassert that it is just a standardising agency. I don’t know why they conducted a study.”

Newslaundry sent a questionnaire to Pramod Kumar Tiwari, director-general of the BIS. The story will be updated if a response is received.