Yamuna's failing last stand in Delhi

The Palla-Wazirabad stretch of the Yamuna, once considered the river's cleanest part, is now succumbing to pollution, data shows

- Jasjeev Gandhiok

Delhi's toxic relationship with the Yamuna is well established now, with the past decade defined by toxic foam, foul stench and unending pollution.

While the stretch from Wazirabad to Okhla is routinely choked with raw sewage, plastic waste and industrial effluents, a 21-kilometre stretch between Palla and Wazirabad, which was considered clean, seems to be succumbing to the Yamuna toxification.

Delhi draws its drinking water from Wazirabad, before the bulk of drains empty into the Yamuna just ahead of this stretch defined by floodplains that host fields of marigold, strawberry and other seasonal produce, perpetuating a belief that this was Delhi's last breath of fresh water.

However, water quality data from the Delhi Pollution Control Committee (DPCC) shows that despite no major drains and sewage outfalls in this stretch, the river's dissolved oxygen (DO) levels-which support aquatic life-fall by an average of 30-40% between the Palla and Wazirabad. The biological oxygen demand (BOD), a marker of organic pollution, roughly doubles.

The state government, since taking office in February, has pledged to rejuvenate the Yamuna on a priority. In June, the government launched a 45-point action plan, specifying strict timelines for ongoing work, including 35 sewage treatment plants (STPs), upgrade of STPs to meet stricter norms, real-time water quality monitoring at 32 locations, trapping 22 major drains that discharge sewage into the river and providing sewer connections to unauthorised colonies. The plan also includes monitoring pollution at 67 key points and using drone surveys.

Key markers