New Delhi: Despite the Delhi government’s renewed commitment to rejuvenate the Yamuna, pollution levels in the river’s upstream stretch between Palla and Wazirabad continue to defy logic and concern experts. Data from the Delhi Pollution Control Committee (DPCC) shows that even in the absence of major sewage outfalls or drains, key water quality parameters in this segment are sharply deteriorating.
According to the DPCC’s July 1 report, the dissolved oxygen (DO), essential for aquatic life, drops by nearly 30% between Palla (4.4 mg/l) and Wazirabad (3.4 mg/l). In June, the dip was even steeper, from 9.2 mg/l to 6.3 mg/l. Similarly, the biological oxygen demand (BOD), a measure of organic pollution, rose from 8 mg/l at Palla to 11 mg/l at Wazirabad, far exceeding the safe limit of 3 mg/l. Faecal coliform levels, an indicator of sewage contamination, also showed troubling spikes. In July, the levels rose from 2,700 MPN/100ml at Palla to 3,900 at Wazirabad, above the permissible threshold of 2,500.
“This deterioration in a supposedly clean stretch points to hidden sources of pollution, possibly unregulated sewage and industrial discharge,” said river expert. He added that settlements in Sonia Vihar and Burari, as well as cross-contamination from stormwater drains, may be to blame.
Trunk Drain No. 8, intended to carry clean water into Delhi, is reportedly being contaminated by adjacent Drain No. 6, which carries industrial effluents. Locals say the river’s colour visibly darkens near Sonia Vihar. “On some mornings, the water turns grey and foamy, it wasn’t like this a few years ago,” said a farmer.
Environmental activist Dhwani Singh warned that illegal units are discharging toxic chemicals into the Yamuna. Despite ongoing clean-up efforts, experts urge urgent upstream action, including fixing Drain No. 8 and identifying pollution sources in floodplains.