New Delhi: River Yamuna appears to have received some of the monsoon cleansing that was due in early July.
In Aug, the river showed a substantial reduction in sewage contamination at some downstream stretches compared to July as well as the same time last year.
A Delhi Pollution Control Committee (DPCC) sample, collected on Aug 5, shows that fecal coliform — an indicator of untreated sewage — fell sharply at several points downstream. At ITO Bridge, the level was 17,000 most probable numbers (MPN)/100 ml, compared with 54,000 a year earlier. At Okhla Barrage, it was 23,000 against 30,000 in Aug 2025. The figures at Nizamuddin Bridge were almost unchanged at 13,000 units, while Asgarpur recorded 36,000 against 35,000 last year. This goes against a desirable limit of 500 MPN/10 ml and a standard of 200 MPN/100 ml. Additional routine monsoon flow began reaching Yamuna from July 9, providing the river with the increased volume needed to dilute and flush accumulated pollutants.
Despite the improvement, though, organic pollution is still high, and a large stretch of the river is still not fit for bathing. The improvement is significant against the backdrop of the river’s condition in early July, when the absence of adequate monsoon flows had left pollution levels largely comparable to June.
At ISBT Bridge, DO rose from 2 mg/l in Aug 2025 to 3 mg/l this year, while at Nizamuddin it increased from 4 mg/l to 4.6 mg/l and at Okhla from 3.2 mg/l to 4 mg/l. At Asgarpur, it rose marginally from 2.3 mg/l to 2.6 mg/l. However, these levels remain below 5 mg/l, which is the standard required for bathing.
The reduction in fecal contamination downstream, therefore, suggests that higher monsoon flows have helped move and dilute some of the sewage load that had accumulated in the river during the lean-flow period. The Aug data also shows some improvement in dissolved oxygen (DO), another measure of the river’s health. But it didn’t translate into uniform improvement in all pollution indicators.