New Delhi: The Ganga water at Triveni Sangam, where lakhs of people are taking a holy dip every day during the ongoing Maha Kumbh, is currently unsafe for bathing as it exceeds the prescribed limit for biological oxygen demand (BOD), a key parameter to determine water quality, according to government data.

BOD refers to the amount of oxygen required by aerobic microorganisms to break down organic material in a water body. A higher BOD level indicates more organic content in the water. River water is considered fit for bathing if the BOD level is less than 3 milligrams per litre. Government data shows that the river water at Sangam is currently exceeding this limit.

The BOD level at Sangam was 5.09 milligrams per litre at 5 am on January 16. It was recorded at 4.6 milligrams per litre at 5 pm on January 18 and 5.29 milligrams per litre at 8 am on January 19 (Wednesday). According to Central Pollution Control Board (CPCB) data, the BOD level at Sangam was 3.94 milligrams per litre on January 13 when the Maha Kumbh started. It improved to 2.28 milligrams per litre on Makar Sankranti (January 14) and further dropped to 1 milligram per litre on January 15. However, it rose to 4.08 milligrams per litre on January 24 and was recorded at 3.26 milligrams per litre on Mauni Amavasya (January 29).

The water at the Sangam is fit for both bathing and ritual drinking (aachman) as confirmed by some recent reports, UP Chief Minister Yogi Adityanath said , amid claims it may contain high levels of faecal bacteria.

He told the state assembly that the Uttar Pradesh Control Board and the Central Pollution Control Board are continuously monitoring the water quality at the Sangam.

He also trained his guns at Opposition Samajwadi Party, saying the condition of the Ganga and Yamuna rivers was so poor while it was in power that the Prime Minister of Mauritius refused to take a dip during the 2013 Kumbh.

"This time, 81 drains have been tapped, treating 261 MLD (million liters per day) of sewage.

In January and February, fecal coliform levels at the Sangam nose were found to be within the acceptable range, below 2,500 MPN per 100 ml, according to the UP Pollution (Control) Board," he said, according to an official statement.

The CM also pointed out that after the stampede at the Prayagraj (then Allahabad) Station in 2013, the then head of the state government was attacking the Centre, then led by the Congress. The Uttar Pradesh government was not receiving funds from the Centre then, and there was "corruption" in whatever money was spent as mentioned in the 2014 CAG report, he said. Adityanath compared the 2013 and 2025 events, and said the duration of the Kumbh is determined by religious calculations.

He said the 2025 event will last 45 days, whereas it spanned 55 days in 2013. The 2013 Kumbh covered an area of only 1,936 hectares (less than 5,000 acres), whereas the 2025 Maha Kumbh Mela area is more than 10,000 acres, he said.