New Delhi: Pollution levels in the Yamuna have shown a sharp decline this year compared with 2025, even though the quality of water flowing into the river from major drains in Delhi and outputs of sewage treatment plants (STPs) in the city have not significantly improved during the same period.According to river analysis reports for this Jan and Feb released by Delhi Pollution Control Committee (DPCC) on Monday, there was a four-time spike in peak levels of faecal coliform this Jan compared with those in Dec 2025.However, when compared with the peak faecal levels — depicting raw sewage — an improvement of 22 times was shown this Jan compared with Jan 2026, while an improvement of 145 times was recorded this Feb 2026 compared with Feb 2025.The peak faecal levels in Jan 2026 was measured at 3.5 lakh MPN/100 ml at Asgarpur, the spot where the Yamuna exits the city. The biochemical oxygen demand (BOD) in the same month peaked at 52 mg/l at Asgarpur. In comparison, in Jan 2025, the peak faecal coliform level was 79 lakh MPN/100 ml, while the BOD was 64 mg/l.Similarly, in Feb 2026, the river recorded the peak faecal level of 1.1 lakh MPN/100 ml and BOD level of 36 mg/l, both at ISBT bridge, while at Asgarpur, the pollution load showed a slight improvement, as compared with the peak faecal level of 1.6 crore MPN/100 ml and BOD of 72 mg/l in Feb 2025.While the drop in faecal levels since Feb 2025 was 145 times, the values recorded at the outlet of the STPs and those in major drains did not show much difference to account for these improvements.“In Feb 2026, the BOD level downstream of Najafgarh drain at ISBT bridge was 36 mg/l despite the confluence of the Najafgarh drain having a level of 65 mg/l. However, in the report, we further see that the BOD levels were improving, even though the Sen Nursing Home drain and Power House drain had higher BOD levels. How can the pollution load in the river improve when there is no major change in the pollution load of corresponding drains?” asked Pankaj Kumar, an environmental activist of Earth Warrior.The water quality furnished by DPCC in Feb 2025 was almost the same as in Feb 2026, yet the Yamuna has shown a major improvement, he said, adding, “Three major drains, including Shahdara, had almost similar BOD levels as they did last year”. The safe limit for faecal coliform is 2,500, and the desired level is below 500 MPN/100 ml. Thus, despite govt data showing improvement in river quality since last year, the latest faecal coliform level recorded in Feb was 44 times the standard and 220 times the desired limit.
