The Ganga water at the Triveni Sangam in Prayagraj, 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.
The Central Pollution Control Board (CPCB) recently told the National Green Tribunal that several locations in Uttar Pradesh’s Prayagraj do not conform to the primary water quality standards for bathing with respect to faecal coliform levels.
However, it said that the river water quality met the bathing criteria in terms of BOD after January 13 ‘due to freshwater intrusion at upstream locations’.
Government data shows that the river water at Sangam is currently exceeding the safe limit for BOD as well.
The BOD level at Sangam was 5.09 milligrams per litre at 5 am on February 16. It was recorded at 4.6 milligrams per litre at 5 pm on February 18 and 5.29 milligrams per litre at 8 am on February 19 (Wednesday).
According to CPCB data as reported by PTI , 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). According to Uttar Pradesh government officials, 10,000 to 11,000 cusecs of water is being released into the Ganga to ensure it meets bathing standards.
